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authorAlex AUVOLAT <alexis211@gmail.com>2012-05-19 11:45:49 +0200
committerAlex AUVOLAT <alexis211@gmail.com>2012-05-19 11:45:49 +0200
commit499ca6c243b05da176a2d4bd9a2317f0b28afc7f (patch)
treef55ff788632b017ab8de83b71ad02b0998e1dda5 /src/user/lib/std/_dlmalloc.c
parent7b466345af0d3a7dc5622617ce443a90c64e34a4 (diff)
downloadTCE-499ca6c243b05da176a2d4bd9a2317f0b28afc7f.tar.gz
TCE-499ca6c243b05da176a2d4bd9a2317f0b28afc7f.zip
Introducing FWIK, the userland C++ framework. Far from complete.
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-/*
- This is a version (aka dlmalloc) of malloc/free/realloc written by
- Doug Lea and released to the public domain, as explained at
- http://creativecommons.org/publicdomain/zero/1.0/ Send questions,
- comments, complaints, performance data, etc to dl@cs.oswego.edu
-
-* Version 2.8.5 Sun May 22 10:26:02 2011 Doug Lea (dl at gee)
-
- Note: There may be an updated version of this malloc obtainable at
- ftp://gee.cs.oswego.edu/pub/misc/malloc.c
- Check before installing!
-
-* Quickstart
-
- This library is all in one file to simplify the most common usage:
- ftp it, compile it (-O3), and link it into another program. All of
- the compile-time options default to reasonable values for use on
- most platforms. You might later want to step through various
- compile-time and dynamic tuning options.
-
- For convenience, an include file for code using this malloc is at:
- ftp://gee.cs.oswego.edu/pub/misc/malloc-2.8.5.h
- You don't really need this .h file unless you call functions not
- defined in your system include files. The .h file contains only the
- excerpts from this file needed for using this malloc on ANSI C/C++
- systems, so long as you haven't changed compile-time options about
- naming and tuning parameters. If you do, then you can create your
- own malloc.h that does include all settings by cutting at the point
- indicated below. Note that you may already by default be using a C
- library containing a malloc that is based on some version of this
- malloc (for example in linux). You might still want to use the one
- in this file to customize settings or to avoid overheads associated
- with library versions.
-
-* Vital statistics:
-
- Supported pointer/size_t representation: 4 or 8 bytes
- size_t MUST be an unsigned type of the same width as
- pointers. (If you are using an ancient system that declares
- size_t as a signed type, or need it to be a different width
- than pointers, you can use a previous release of this malloc
- (e.g. 2.7.2) supporting these.)
-
- Alignment: 8 bytes (default)
- This suffices for nearly all current machines and C compilers.
- However, you can define MALLOC_ALIGNMENT to be wider than this
- if necessary (up to 128bytes), at the expense of using more space.
-
- Minimum overhead per allocated chunk: 4 or 8 bytes (if 4byte sizes)
- 8 or 16 bytes (if 8byte sizes)
- Each malloced chunk has a hidden word of overhead holding size
- and status information, and additional cross-check word
- if FOOTERS is defined.
-
- Minimum allocated size: 4-byte ptrs: 16 bytes (including overhead)
- 8-byte ptrs: 32 bytes (including overhead)
-
- Even a request for zero bytes (i.e., malloc(0)) returns a
- pointer to something of the minimum allocatable size.
- The maximum overhead wastage (i.e., number of extra bytes
- allocated than were requested in malloc) is less than or equal
- to the minimum size, except for requests >= mmap_threshold that
- are serviced via mmap(), where the worst case wastage is about
- 32 bytes plus the remainder from a system page (the minimal
- mmap unit); typically 4096 or 8192 bytes.
-
- Security: static-safe; optionally more or less
- The "security" of malloc refers to the ability of malicious
- code to accentuate the effects of errors (for example, freeing
- space that is not currently malloc'ed or overwriting past the
- ends of chunks) in code that calls malloc. This malloc
- guarantees not to modify any memory locations below the base of
- heap, i.e., static variables, even in the presence of usage
- errors. The routines additionally detect most improper frees
- and reallocs. All this holds as long as the static bookkeeping
- for malloc itself is not corrupted by some other means. This
- is only one aspect of security -- these checks do not, and
- cannot, detect all possible programming errors.
-
- If FOOTERS is defined nonzero, then each allocated chunk
- carries an additional check word to verify that it was malloced
- from its space. These check words are the same within each
- execution of a program using malloc, but differ across
- executions, so externally crafted fake chunks cannot be
- freed. This improves security by rejecting frees/reallocs that
- could corrupt heap memory, in addition to the checks preventing
- writes to statics that are always on. This may further improve
- security at the expense of time and space overhead. (Note that
- FOOTERS may also be worth using with MSPACES.)
-
- By default detected errors cause the program to abort (calling
- "abort()"). You can override this to instead proceed past
- errors by defining PROCEED_ON_ERROR. In this case, a bad free
- has no effect, and a malloc that encounters a bad address
- caused by user overwrites will ignore the bad address by
- dropping pointers and indices to all known memory. This may
- be appropriate for programs that should continue if at all
- possible in the face of programming errors, although they may
- run out of memory because dropped memory is never reclaimed.
-
- If you don't like either of these options, you can define
- CORRUPTION_ERROR_ACTION and USAGE_ERROR_ACTION to do anything
- else. And if if you are sure that your program using malloc has
- no errors or vulnerabilities, you can define INSECURE to 1,
- which might (or might not) provide a small performance improvement.
-
- It is also possible to limit the maximum total allocatable
- space, using malloc_set_footprint_limit. This is not
- designed as a security feature in itself (calls to set limits
- are not screened or privileged), but may be useful as one
- aspect of a secure implementation.
-
- Thread-safety: NOT thread-safe unless USE_LOCKS defined non-zero
- When USE_LOCKS is defined, each public call to malloc, free,
- etc is surrounded with a lock. By default, this uses a plain
- pthread mutex, win32 critical section, or a spin-lock if if
- available for the platform and not disabled by setting
- USE_SPIN_LOCKS=0. However, if USE_RECURSIVE_LOCKS is defined,
- recursive versions are used instead (which are not required for
- base functionality but may be needed in layered extensions).
- Using a global lock is not especially fast, and can be a major
- bottleneck. It is designed only to provide minimal protection
- in concurrent environments, and to provide a basis for
- extensions. If you are using malloc in a concurrent program,
- consider instead using nedmalloc
- (http://www.nedprod.com/programs/portable/nedmalloc/) or
- ptmalloc (See http://www.malloc.de), which are derived from
- versions of this malloc.
-
- System requirements: Any combination of MORECORE and/or MMAP/MUNMAP
- This malloc can use unix sbrk or any emulation (invoked using
- the CALL_MORECORE macro) and/or mmap/munmap or any emulation
- (invoked using CALL_MMAP/CALL_MUNMAP) to get and release system
- memory. On most unix systems, it tends to work best if both
- MORECORE and MMAP are enabled. On Win32, it uses emulations
- based on VirtualAlloc. It also uses common C library functions
- like memset.
-
- Compliance: I believe it is compliant with the Single Unix Specification
- (See http://www.unix.org). Also SVID/XPG, ANSI C, and probably
- others as well.
-
-* Overview of algorithms
-
- This is not the fastest, most space-conserving, most portable, or
- most tunable malloc ever written. However it is among the fastest
- while also being among the most space-conserving, portable and
- tunable. Consistent balance across these factors results in a good
- general-purpose allocator for malloc-intensive programs.
-
- In most ways, this malloc is a best-fit allocator. Generally, it
- chooses the best-fitting existing chunk for a request, with ties
- broken in approximately least-recently-used order. (This strategy
- normally maintains low fragmentation.) However, for requests less
- than 256bytes, it deviates from best-fit when there is not an
- exactly fitting available chunk by preferring to use space adjacent
- to that used for the previous small request, as well as by breaking
- ties in approximately most-recently-used order. (These enhance
- locality of series of small allocations.) And for very large requests
- (>= 256Kb by default), it relies on system memory mapping
- facilities, if supported. (This helps avoid carrying around and
- possibly fragmenting memory used only for large chunks.)
-
- All operations (except malloc_stats and mallinfo) have execution
- times that are bounded by a constant factor of the number of bits in
- a size_t, not counting any clearing in calloc or copying in realloc,
- or actions surrounding MORECORE and MMAP that have times
- proportional to the number of non-contiguous regions returned by
- system allocation routines, which is often just 1. In real-time
- applications, you can optionally suppress segment traversals using
- NO_SEGMENT_TRAVERSAL, which assures bounded execution even when
- system allocators return non-contiguous spaces, at the typical
- expense of carrying around more memory and increased fragmentation.
-
- The implementation is not very modular and seriously overuses
- macros. Perhaps someday all C compilers will do as good a job
- inlining modular code as can now be done by brute-force expansion,
- but now, enough of them seem not to.
-
- Some compilers issue a lot of warnings about code that is
- dead/unreachable only on some platforms, and also about intentional
- uses of negation on unsigned types. All known cases of each can be
- ignored.
-
- For a longer but out of date high-level description, see
- http://gee.cs.oswego.edu/dl/html/malloc.html
-
-* MSPACES
- If MSPACES is defined, then in addition to malloc, free, etc.,
- this file also defines mspace_malloc, mspace_free, etc. These
- are versions of malloc routines that take an "mspace" argument
- obtained using create_mspace, to control all internal bookkeeping.
- If ONLY_MSPACES is defined, only these versions are compiled.
- So if you would like to use this allocator for only some allocations,
- and your system malloc for others, you can compile with
- ONLY_MSPACES and then do something like...
- static mspace mymspace = create_mspace(0,0); // for example
- #define mymalloc(bytes) mspace_malloc(mymspace, bytes)
-
- (Note: If you only need one instance of an mspace, you can instead
- use "USE_DL_PREFIX" to relabel the global malloc.)
-
- You can similarly create thread-local allocators by storing
- mspaces as thread-locals. For example:
- static __thread mspace tlms = 0;
- void* tlmalloc(size_t bytes) {
- if (tlms == 0) tlms = create_mspace(0, 0);
- return mspace_malloc(tlms, bytes);
- }
- void tlfree(void* mem) { mspace_free(tlms, mem); }
-
- Unless FOOTERS is defined, each mspace is completely independent.
- You cannot allocate from one and free to another (although
- conformance is only weakly checked, so usage errors are not always
- caught). If FOOTERS is defined, then each chunk carries around a tag
- indicating its originating mspace, and frees are directed to their
- originating spaces. Normally, this requires use of locks.
-
- ------------------------- Compile-time options ---------------------------
-
-Be careful in setting #define values for numerical constants of type
-size_t. On some systems, literal values are not automatically extended
-to size_t precision unless they are explicitly casted. You can also
-use the symbolic values MAX_SIZE_T, SIZE_T_ONE, etc below.
-
-WIN32 default: defined if _WIN32 defined
- Defining WIN32 sets up defaults for MS environment and compilers.
- Otherwise defaults are for unix. Beware that there seem to be some
- cases where this malloc might not be a pure drop-in replacement for
- Win32 malloc: Random-looking failures from Win32 GDI API's (eg;
- SetDIBits()) may be due to bugs in some video driver implementations
- when pixel buffers are malloc()ed, and the region spans more than
- one VirtualAlloc()ed region. Because dlmalloc uses a small (64Kb)
- default granularity, pixel buffers may straddle virtual allocation
- regions more often than when using the Microsoft allocator. You can
- avoid this by using VirtualAlloc() and VirtualFree() for all pixel
- buffers rather than using malloc(). If this is not possible,
- recompile this malloc with a larger DEFAULT_GRANULARITY. Note:
- in cases where MSC and gcc (cygwin) are known to differ on WIN32,
- conditions use _MSC_VER to distinguish them.
-
-DLMALLOC_EXPORT default: extern
- Defines how public APIs are declared. If you want to export via a
- Windows DLL, you might define this as
- #define DLMALLOC_EXPORT extern __declspace(dllexport)
- If you want a POSIX ELF shared object, you might use
- #define DLMALLOC_EXPORT extern __attribute__((visibility("default")))
-
-MALLOC_ALIGNMENT default: (size_t)8
- Controls the minimum alignment for malloc'ed chunks. It must be a
- power of two and at least 8, even on machines for which smaller
- alignments would suffice. It may be defined as larger than this
- though. Note however that code and data structures are optimized for
- the case of 8-byte alignment.
-
-MSPACES default: 0 (false)
- If true, compile in support for independent allocation spaces.
- This is only supported if HAVE_MMAP is true.
-
-ONLY_MSPACES default: 0 (false)
- If true, only compile in mspace versions, not regular versions.
-
-USE_LOCKS default: 0 (false)
- Causes each call to each public routine to be surrounded with
- pthread or WIN32 mutex lock/unlock. (If set true, this can be
- overridden on a per-mspace basis for mspace versions.) If set to a
- non-zero value other than 1, locks are used, but their
- implementation is left out, so lock functions must be supplied manually,
- as described below.
-
-USE_SPIN_LOCKS default: 1 iff USE_LOCKS and spin locks available
- If true, uses custom spin locks for locking. This is currently
- supported only gcc >= 4.1, older gccs on x86 platforms, and recent
- MS compilers. Otherwise, posix locks or win32 critical sections are
- used.
-
-USE_RECURSIVE_LOCKS default: not defined
- If defined nonzero, uses recursive (aka reentrant) locks, otherwise
- uses plain mutexes. This is not required for malloc proper, but may
- be needed for layered allocators such as nedmalloc.
-
-FOOTERS default: 0
- If true, provide extra checking and dispatching by placing
- information in the footers of allocated chunks. This adds
- space and time overhead.
-
-INSECURE default: 0
- If true, omit checks for usage errors and heap space overwrites.
-
-USE_DL_PREFIX default: NOT defined
- Causes compiler to prefix all public routines with the string 'dl'.
- This can be useful when you only want to use this malloc in one part
- of a program, using your regular system malloc elsewhere.
-
-MALLOC_INSPECT_ALL default: NOT defined
- If defined, compiles malloc_inspect_all and mspace_inspect_all, that
- perform traversal of all heap space. Unless access to these
- functions is otherwise restricted, you probably do not want to
- include them in secure implementations.
-
-ABORT default: defined as abort()
- Defines how to abort on failed checks. On most systems, a failed
- check cannot die with an "assert" or even print an informative
- message, because the underlying print routines in turn call malloc,
- which will fail again. Generally, the best policy is to simply call
- abort(). It's not very useful to do more than this because many
- errors due to overwriting will show up as address faults (null, odd
- addresses etc) rather than malloc-triggered checks, so will also
- abort. Also, most compilers know that abort() does not return, so
- can better optimize code conditionally calling it.
-
-PROCEED_ON_ERROR default: defined as 0 (false)
- Controls whether detected bad addresses cause them to bypassed
- rather than aborting. If set, detected bad arguments to free and
- realloc are ignored. And all bookkeeping information is zeroed out
- upon a detected overwrite of freed heap space, thus losing the
- ability to ever return it from malloc again, but enabling the
- application to proceed. If PROCEED_ON_ERROR is defined, the
- static variable malloc_corruption_error_count is compiled in
- and can be examined to see if errors have occurred. This option
- generates slower code than the default abort policy.
-
-DEBUG default: NOT defined
- The DEBUG setting is mainly intended for people trying to modify
- this code or diagnose problems when porting to new platforms.
- However, it may also be able to better isolate user errors than just
- using runtime checks. The assertions in the check routines spell
- out in more detail the assumptions and invariants underlying the
- algorithms. The checking is fairly extensive, and will slow down
- execution noticeably. Calling malloc_stats or mallinfo with DEBUG
- set will attempt to check every non-mmapped allocated and free chunk
- in the course of computing the summaries.
-
-ABORT_ON_ASSERT_FAILURE default: defined as 1 (true)
- Debugging assertion failures can be nearly impossible if your
- version of the assert macro causes malloc to be called, which will
- lead to a cascade of further failures, blowing the runtime stack.
- ABORT_ON_ASSERT_FAILURE cause assertions failures to call abort(),
- which will usually make debugging easier.
-
-MALLOC_FAILURE_ACTION default: sets errno to ENOMEM, or no-op on win32
- The action to take before "return 0" when malloc fails to be able to
- return memory because there is none available.
-
-HAVE_MORECORE default: 1 (true) unless win32 or ONLY_MSPACES
- True if this system supports sbrk or an emulation of it.
-
-MORECORE default: sbrk
- The name of the sbrk-style system routine to call to obtain more
- memory. See below for guidance on writing custom MORECORE
- functions. The type of the argument to sbrk/MORECORE varies across
- systems. It cannot be size_t, because it supports negative
- arguments, so it is normally the signed type of the same width as
- size_t (sometimes declared as "intptr_t"). It doesn't much matter
- though. Internally, we only call it with arguments less than half
- the max value of a size_t, which should work across all reasonable
- possibilities, although sometimes generating compiler warnings.
-
-MORECORE_CONTIGUOUS default: 1 (true) if HAVE_MORECORE
- If true, take advantage of fact that consecutive calls to MORECORE
- with positive arguments always return contiguous increasing
- addresses. This is true of unix sbrk. It does not hurt too much to
- set it true anyway, since malloc copes with non-contiguities.
- Setting it false when definitely non-contiguous saves time
- and possibly wasted space it would take to discover this though.
-
-MORECORE_CANNOT_TRIM default: NOT defined
- True if MORECORE cannot release space back to the system when given
- negative arguments. This is generally necessary only if you are
- using a hand-crafted MORECORE function that cannot handle negative
- arguments.
-
-NO_SEGMENT_TRAVERSAL default: 0
- If non-zero, suppresses traversals of memory segments
- returned by either MORECORE or CALL_MMAP. This disables
- merging of segments that are contiguous, and selectively
- releasing them to the OS if unused, but bounds execution times.
-
-HAVE_MMAP default: 1 (true)
- True if this system supports mmap or an emulation of it. If so, and
- HAVE_MORECORE is not true, MMAP is used for all system
- allocation. If set and HAVE_MORECORE is true as well, MMAP is
- primarily used to directly allocate very large blocks. It is also
- used as a backup strategy in cases where MORECORE fails to provide
- space from system. Note: A single call to MUNMAP is assumed to be
- able to unmap memory that may have be allocated using multiple calls
- to MMAP, so long as they are adjacent.
-
-HAVE_MREMAP default: 1 on linux, else 0
- If true realloc() uses mremap() to re-allocate large blocks and
- extend or shrink allocation spaces.
-
-MMAP_CLEARS default: 1 except on WINCE.
- True if mmap clears memory so calloc doesn't need to. This is true
- for standard unix mmap using /dev/zero and on WIN32 except for WINCE.
-
-USE_BUILTIN_FFS default: 0 (i.e., not used)
- Causes malloc to use the builtin ffs() function to compute indices.
- Some compilers may recognize and intrinsify ffs to be faster than the
- supplied C version. Also, the case of x86 using gcc is special-cased
- to an asm instruction, so is already as fast as it can be, and so
- this setting has no effect. Similarly for Win32 under recent MS compilers.
- (On most x86s, the asm version is only slightly faster than the C version.)
-
-malloc_getpagesize default: derive from system includes, or 4096.
- The system page size. To the extent possible, this malloc manages
- memory from the system in page-size units. This may be (and
- usually is) a function rather than a constant. This is ignored
- if WIN32, where page size is determined using getSystemInfo during
- initialization.
-
-USE_DEV_RANDOM default: 0 (i.e., not used)
- Causes malloc to use /dev/random to initialize secure magic seed for
- stamping footers. Otherwise, the current time is used.
-
-NO_MALLINFO default: 0
- If defined, don't compile "mallinfo". This can be a simple way
- of dealing with mismatches between system declarations and
- those in this file.
-
-MALLINFO_FIELD_TYPE default: size_t
- The type of the fields in the mallinfo struct. This was originally
- defined as "int" in SVID etc, but is more usefully defined as
- size_t. The value is used only if HAVE_USR_INCLUDE_MALLOC_H is not set
-
-NO_MALLOC_STATS default: 0
- If defined, don't compile "malloc_stats". This avoids calls to
- fprintf and bringing in stdio dependencies you might not want.
-
-REALLOC_ZERO_BYTES_FREES default: not defined
- This should be set if a call to realloc with zero bytes should
- be the same as a call to free. Some people think it should. Otherwise,
- since this malloc returns a unique pointer for malloc(0), so does
- realloc(p, 0).
-
-LACKS_UNISTD_H, LACKS_FCNTL_H, LACKS_SYS_PARAM_H, LACKS_SYS_MMAN_H
-LACKS_STRINGS_H, LACKS_STRING_H, LACKS_SYS_TYPES_H, LACKS_ERRNO_H
-LACKS_STDLIB_H LACKS_SCHED_H LACKS_TIME_H default: NOT defined unless on WIN32
- Define these if your system does not have these header files.
- You might need to manually insert some of the declarations they provide.
-
-DEFAULT_GRANULARITY default: page size if MORECORE_CONTIGUOUS,
- system_info.dwAllocationGranularity in WIN32,
- otherwise 64K.
- Also settable using mallopt(M_GRANULARITY, x)
- The unit for allocating and deallocating memory from the system. On
- most systems with contiguous MORECORE, there is no reason to
- make this more than a page. However, systems with MMAP tend to
- either require or encourage larger granularities. You can increase
- this value to prevent system allocation functions to be called so
- often, especially if they are slow. The value must be at least one
- page and must be a power of two. Setting to 0 causes initialization
- to either page size or win32 region size. (Note: In previous
- versions of malloc, the equivalent of this option was called
- "TOP_PAD")
-
-DEFAULT_TRIM_THRESHOLD default: 2MB
- Also settable using mallopt(M_TRIM_THRESHOLD, x)
- The maximum amount of unused top-most memory to keep before
- releasing via malloc_trim in free(). Automatic trimming is mainly
- useful in long-lived programs using contiguous MORECORE. Because
- trimming via sbrk can be slow on some systems, and can sometimes be
- wasteful (in cases where programs immediately afterward allocate
- more large chunks) the value should be high enough so that your
- overall system performance would improve by releasing this much
- memory. As a rough guide, you might set to a value close to the
- average size of a process (program) running on your system.
- Releasing this much memory would allow such a process to run in
- memory. Generally, it is worth tuning trim thresholds when a
- program undergoes phases where several large chunks are allocated
- and released in ways that can reuse each other's storage, perhaps
- mixed with phases where there are no such chunks at all. The trim
- value must be greater than page size to have any useful effect. To
- disable trimming completely, you can set to MAX_SIZE_T. Note that the trick
- some people use of mallocing a huge space and then freeing it at
- program startup, in an attempt to reserve system memory, doesn't
- have the intended effect under automatic trimming, since that memory
- will immediately be returned to the system.
-
-DEFAULT_MMAP_THRESHOLD default: 256K
- Also settable using mallopt(M_MMAP_THRESHOLD, x)
- The request size threshold for using MMAP to directly service a
- request. Requests of at least this size that cannot be allocated
- using already-existing space will be serviced via mmap. (If enough
- normal freed space already exists it is used instead.) Using mmap
- segregates relatively large chunks of memory so that they can be
- individually obtained and released from the host system. A request
- serviced through mmap is never reused by any other request (at least
- not directly; the system may just so happen to remap successive
- requests to the same locations). Segregating space in this way has
- the benefits that: Mmapped space can always be individually released
- back to the system, which helps keep the system level memory demands
- of a long-lived program low. Also, mapped memory doesn't become
- `locked' between other chunks, as can happen with normally allocated
- chunks, which means that even trimming via malloc_trim would not
- release them. However, it has the disadvantage that the space
- cannot be reclaimed, consolidated, and then used to service later
- requests, as happens with normal chunks. The advantages of mmap
- nearly always outweigh disadvantages for "large" chunks, but the
- value of "large" may vary across systems. The default is an
- empirically derived value that works well in most systems. You can
- disable mmap by setting to MAX_SIZE_T.
-
-MAX_RELEASE_CHECK_RATE default: 4095 unless not HAVE_MMAP
- The number of consolidated frees between checks to release
- unused segments when freeing. When using non-contiguous segments,
- especially with multiple mspaces, checking only for topmost space
- doesn't always suffice to trigger trimming. To compensate for this,
- free() will, with a period of MAX_RELEASE_CHECK_RATE (or the
- current number of segments, if greater) try to release unused
- segments to the OS when freeing chunks that result in
- consolidation. The best value for this parameter is a compromise
- between slowing down frees with relatively costly checks that
- rarely trigger versus holding on to unused memory. To effectively
- disable, set to MAX_SIZE_T. This may lead to a very slight speed
- improvement at the expense of carrying around more memory.
-*/
-
-
-/*
- ========================================================================
- To make a fully customizable malloc.h header file, cut everything
- above this line, put into file malloc.h, edit to suit, and #include it
- on the next line, as well as in programs that use this malloc.
- ========================================================================
-*/
-
-#include <_dlmalloc.h>
-
-/*------------------------------ internal #includes ---------------------- */
-
-#ifdef _MSC_VER
-#pragma warning( disable : 4146 ) /* no "unsigned" warnings */
-#endif /* _MSC_VER */
-#if !NO_MALLOC_STATS
-#include <stdio.h> /* for printing in malloc_stats */
-#endif /* NO_MALLOC_STATS */
-#ifndef LACKS_ERRNO_H
-#include <errno.h> /* for MALLOC_FAILURE_ACTION */
-#endif /* LACKS_ERRNO_H */
-#ifdef DEBUG
-#if ABORT_ON_ASSERT_FAILURE
-#undef assert
-#define assert(x) if(!(x)) ABORT
-#else /* ABORT_ON_ASSERT_FAILURE */
-#include <assert.h>
-#endif /* ABORT_ON_ASSERT_FAILURE */
-#else /* DEBUG */
-#ifndef assert
-#define assert(x)
-#endif
-#define DEBUG 0
-#endif /* DEBUG */
-#if !defined(WIN32) && !defined(LACKS_TIME_H)
-#include <time.h> /* for magic initialization */
-#endif /* WIN32 */
-#ifndef LACKS_STDLIB_H
-#include <stdlib.h> /* for abort() */
-#endif /* LACKS_STDLIB_H */
-#ifndef LACKS_STRING_H
-#include <string.h> /* for memset etc */
-#endif /* LACKS_STRING_H */
-#if USE_BUILTIN_FFS
-#ifndef LACKS_STRINGS_H
-#include <strings.h> /* for ffs */
-#endif /* LACKS_STRINGS_H */
-#endif /* USE_BUILTIN_FFS */
-#if HAVE_MMAP
-#ifndef LACKS_SYS_MMAN_H
-/* On some versions of linux, mremap decl in mman.h needs __USE_GNU set */
-#if (defined(linux) && !defined(__USE_GNU))
-#define __USE_GNU 1
-#include <sys/mman.h> /* for mmap */
-#undef __USE_GNU
-#else
-#include <sys/mman.h> /* for mmap */
-#endif /* linux */
-#endif /* LACKS_SYS_MMAN_H */
-#ifndef LACKS_FCNTL_H
-#include <fcntl.h>
-#endif /* LACKS_FCNTL_H */
-#endif /* HAVE_MMAP */
-#ifndef LACKS_UNISTD_H
-#include <unistd.h> /* for sbrk, sysconf */
-#else /* LACKS_UNISTD_H */
-#if !defined(__FreeBSD__) && !defined(__OpenBSD__) && !defined(__NetBSD__)
-extern void* sbrk(ptrdiff_t);
-#endif /* FreeBSD etc */
-#endif /* LACKS_UNISTD_H */
-
-/* Declarations for locking */
-#if USE_LOCKS
-#ifndef WIN32
-#if defined (__SVR4) && defined (__sun) /* solaris */
-#include <thread.h>
-#elif !defined(LACKS_SCHED_H)
-#include <sched.h>
-#endif /* solaris or LACKS_SCHED_H */
-#if (defined(USE_RECURSIVE_LOCKS) && USE_RECURSIVE_LOCKS != 0) || !USE_SPIN_LOCKS
-#include <pthread.h>
-#endif /* USE_RECURSIVE_LOCKS ... */
-#elif defined(_MSC_VER)
-#ifndef _M_AMD64
-/* These are already defined on AMD64 builds */
-#ifdef __cplusplus
-extern "C" {
-#endif /* __cplusplus */
-LONG __cdecl _InterlockedCompareExchange(LONG volatile *Dest, LONG Exchange, LONG Comp);
-LONG __cdecl _InterlockedExchange(LONG volatile *Target, LONG Value);
-#ifdef __cplusplus
-}
-#endif /* __cplusplus */
-#endif /* _M_AMD64 */
-#pragma intrinsic (_InterlockedCompareExchange)
-#pragma intrinsic (_InterlockedExchange)
-#define interlockedcompareexchange _InterlockedCompareExchange
-#define interlockedexchange _InterlockedExchange
-#elif defined(WIN32) && defined(__GNUC__)
-#define interlockedcompareexchange(a, b, c) __sync_val_compare_and_swap(a, c, b)
-#define interlockedexchange __sync_lock_test_and_set
-#endif /* Win32 */
-#endif /* USE_LOCKS */
-
-/* Declarations for bit scanning on win32 */
-#if defined(_MSC_VER) && _MSC_VER>=1300
-#ifndef BitScanForward /* Try to avoid pulling in WinNT.h */
-#ifdef __cplusplus
-extern "C" {
-#endif /* __cplusplus */
-unsigned char _BitScanForward(unsigned long *index, unsigned long mask);
-unsigned char _BitScanReverse(unsigned long *index, unsigned long mask);
-#ifdef __cplusplus
-}
-#endif /* __cplusplus */
-
-#define BitScanForward _BitScanForward
-#define BitScanReverse _BitScanReverse
-#pragma intrinsic(_BitScanForward)
-#pragma intrinsic(_BitScanReverse)
-#endif /* BitScanForward */
-#endif /* defined(_MSC_VER) && _MSC_VER>=1300 */
-
-#ifndef WIN32
-#ifndef malloc_getpagesize
-# ifdef _SC_PAGESIZE /* some SVR4 systems omit an underscore */
-# ifndef _SC_PAGE_SIZE
-# define _SC_PAGE_SIZE _SC_PAGESIZE
-# endif
-# endif
-# ifdef _SC_PAGE_SIZE
-# define malloc_getpagesize sysconf(_SC_PAGE_SIZE)
-# else
-# if defined(BSD) || defined(DGUX) || defined(HAVE_GETPAGESIZE)
- extern size_t getpagesize();
-# define malloc_getpagesize getpagesize()
-# else
-# ifdef WIN32 /* use supplied emulation of getpagesize */
-# define malloc_getpagesize getpagesize()
-# else
-# ifndef LACKS_SYS_PARAM_H
-# include <sys/param.h>
-# endif
-# ifdef EXEC_PAGESIZE
-# define malloc_getpagesize EXEC_PAGESIZE
-# else
-# ifdef NBPG
-# ifndef CLSIZE
-# define malloc_getpagesize NBPG
-# else
-# define malloc_getpagesize (NBPG * CLSIZE)
-# endif
-# else
-# ifdef NBPC
-# define malloc_getpagesize NBPC
-# else
-# ifdef PAGESIZE
-# define malloc_getpagesize PAGESIZE
-# else /* just guess */
-# define malloc_getpagesize ((size_t)4096U)
-# endif
-# endif
-# endif
-# endif
-# endif
-# endif
-# endif
-#endif
-#endif
-
-/* ------------------- size_t and alignment properties -------------------- */
-
-/* The byte and bit size of a size_t */
-#define SIZE_T_SIZE (sizeof(size_t))
-#define SIZE_T_BITSIZE (sizeof(size_t) << 3)
-
-/* Some constants coerced to size_t */
-/* Annoying but necessary to avoid errors on some platforms */
-#define SIZE_T_ZERO ((size_t)0)
-#define SIZE_T_ONE ((size_t)1)
-#define SIZE_T_TWO ((size_t)2)
-#define SIZE_T_FOUR ((size_t)4)
-#define TWO_SIZE_T_SIZES (SIZE_T_SIZE<<1)
-#define FOUR_SIZE_T_SIZES (SIZE_T_SIZE<<2)
-#define SIX_SIZE_T_SIZES (FOUR_SIZE_T_SIZES+TWO_SIZE_T_SIZES)
-#define HALF_MAX_SIZE_T (MAX_SIZE_T / 2U)
-
-/* The bit mask value corresponding to MALLOC_ALIGNMENT */
-#define CHUNK_ALIGN_MASK (MALLOC_ALIGNMENT - SIZE_T_ONE)
-
-/* True if address a has acceptable alignment */
-#define is_aligned(A) (((size_t)((A)) & (CHUNK_ALIGN_MASK)) == 0)
-
-/* the number of bytes to offset an address to align it */
-#define align_offset(A)\
- ((((size_t)(A) & CHUNK_ALIGN_MASK) == 0)? 0 :\
- ((MALLOC_ALIGNMENT - ((size_t)(A) & CHUNK_ALIGN_MASK)) & CHUNK_ALIGN_MASK))
-
-/* -------------------------- MMAP preliminaries ------------------------- */
-
-/*
- If HAVE_MORECORE or HAVE_MMAP are false, we just define calls and
- checks to fail so compiler optimizer can delete code rather than
- using so many "#if"s.
-*/
-
-
-/* MORECORE and MMAP must return MFAIL on failure */
-#define MFAIL ((void*)(MAX_SIZE_T))
-#define CMFAIL ((char*)(MFAIL)) /* defined for convenience */
-
-#if HAVE_MMAP
-
-#ifndef WIN32
-#define MUNMAP_DEFAULT(a, s) munmap((a), (s))
-#define MMAP_PROT (PROT_READ|PROT_WRITE)
-#if !defined(MAP_ANONYMOUS) && defined(MAP_ANON)
-#define MAP_ANONYMOUS MAP_ANON
-#endif /* MAP_ANON */
-#ifdef MAP_ANONYMOUS
-#define MMAP_FLAGS (MAP_PRIVATE|MAP_ANONYMOUS)
-#define MMAP_DEFAULT(s) mmap(0, (s), MMAP_PROT, MMAP_FLAGS, -1, 0)
-#else /* MAP_ANONYMOUS */
-/*
- Nearly all versions of mmap support MAP_ANONYMOUS, so the following
- is unlikely to be needed, but is supplied just in case.
-*/
-#define MMAP_FLAGS (MAP_PRIVATE)
-static int dev_zero_fd = -1; /* Cached file descriptor for /dev/zero. */
-#define MMAP_DEFAULT(s) ((dev_zero_fd < 0) ? \
- (dev_zero_fd = open("/dev/zero", O_RDWR), \
- mmap(0, (s), MMAP_PROT, MMAP_FLAGS, dev_zero_fd, 0)) : \
- mmap(0, (s), MMAP_PROT, MMAP_FLAGS, dev_zero_fd, 0))
-#endif /* MAP_ANONYMOUS */
-
-#define DIRECT_MMAP_DEFAULT(s) MMAP_DEFAULT(s)
-
-#else /* WIN32 */
-
-/* Win32 MMAP via VirtualAlloc */
-static FORCEINLINE void* win32mmap(size_t size) {
- void* ptr = VirtualAlloc(0, size, MEM_RESERVE|MEM_COMMIT, PAGE_READWRITE);
- return (ptr != 0)? ptr: MFAIL;
-}
-
-/* For direct MMAP, use MEM_TOP_DOWN to minimize interference */
-static FORCEINLINE void* win32direct_mmap(size_t size) {
- void* ptr = VirtualAlloc(0, size, MEM_RESERVE|MEM_COMMIT|MEM_TOP_DOWN,
- PAGE_READWRITE);
- return (ptr != 0)? ptr: MFAIL;
-}
-
-/* This function supports releasing coalesed segments */
-static FORCEINLINE int win32munmap(void* ptr, size_t size) {
- MEMORY_BASIC_INFORMATION minfo;
- char* cptr = (char*)ptr;
- while (size) {
- if (VirtualQuery(cptr, &minfo, sizeof(minfo)) == 0)
- return -1;
- if (minfo.BaseAddress != cptr || minfo.AllocationBase != cptr ||
- minfo.State != MEM_COMMIT || minfo.RegionSize > size)
- return -1;
- if (VirtualFree(cptr, 0, MEM_RELEASE) == 0)
- return -1;
- cptr += minfo.RegionSize;
- size -= minfo.RegionSize;
- }
- return 0;
-}
-
-#define MMAP_DEFAULT(s) win32mmap(s)
-#define MUNMAP_DEFAULT(a, s) win32munmap((a), (s))
-#define DIRECT_MMAP_DEFAULT(s) win32direct_mmap(s)
-#endif /* WIN32 */
-#endif /* HAVE_MMAP */
-
-#if HAVE_MREMAP
-#ifndef WIN32
-#define MREMAP_DEFAULT(addr, osz, nsz, mv) mremap((addr), (osz), (nsz), (mv))
-#endif /* WIN32 */
-#endif /* HAVE_MREMAP */
-
-/**
- * Define CALL_MORECORE
- */
-#if HAVE_MORECORE
- #ifdef MORECORE
- #define CALL_MORECORE(S) MORECORE(S)
- #else /* MORECORE */
- #define CALL_MORECORE(S) MORECORE_DEFAULT(S)
- #endif /* MORECORE */
-#else /* HAVE_MORECORE */
- #define CALL_MORECORE(S) MFAIL
-#endif /* HAVE_MORECORE */
-
-/**
- * Define CALL_MMAP/CALL_MUNMAP/CALL_DIRECT_MMAP
- */
-#if HAVE_MMAP
- #define USE_MMAP_BIT (SIZE_T_ONE)
-
- #ifdef MMAP
- #define CALL_MMAP(s) MMAP(s)
- #else /* MMAP */
- #define CALL_MMAP(s) MMAP_DEFAULT(s)
- #endif /* MMAP */
- #ifdef MUNMAP
- #define CALL_MUNMAP(a, s) MUNMAP((a), (s))
- #else /* MUNMAP */
- #define CALL_MUNMAP(a, s) MUNMAP_DEFAULT((a), (s))
- #endif /* MUNMAP */
- #ifdef DIRECT_MMAP
- #define CALL_DIRECT_MMAP(s) DIRECT_MMAP(s)
- #else /* DIRECT_MMAP */
- #define CALL_DIRECT_MMAP(s) DIRECT_MMAP_DEFAULT(s)
- #endif /* DIRECT_MMAP */
-#else /* HAVE_MMAP */
- #define USE_MMAP_BIT (SIZE_T_ZERO)
-
- #define MMAP(s) MFAIL
- #define MUNMAP(a, s) (-1)
- #define DIRECT_MMAP(s) MFAIL
- #define CALL_DIRECT_MMAP(s) DIRECT_MMAP(s)
- #define CALL_MMAP(s) MMAP(s)
- #define CALL_MUNMAP(a, s) MUNMAP((a), (s))
-#endif /* HAVE_MMAP */
-
-/**
- * Define CALL_MREMAP
- */
-#if HAVE_MMAP && HAVE_MREMAP
- #ifdef MREMAP
- #define CALL_MREMAP(addr, osz, nsz, mv) MREMAP((addr), (osz), (nsz), (mv))
- #else /* MREMAP */
- #define CALL_MREMAP(addr, osz, nsz, mv) MREMAP_DEFAULT((addr), (osz), (nsz), (mv))
- #endif /* MREMAP */
-#else /* HAVE_MMAP && HAVE_MREMAP */
- #define CALL_MREMAP(addr, osz, nsz, mv) MFAIL
-#endif /* HAVE_MMAP && HAVE_MREMAP */
-
-/* mstate bit set if continguous morecore disabled or failed */
-#define USE_NONCONTIGUOUS_BIT (4U)
-
-/* segment bit set in create_mspace_with_base */
-#define EXTERN_BIT (8U)
-
-
-/* --------------------------- Lock preliminaries ------------------------ */
-
-/*
- When locks are defined, there is one global lock, plus
- one per-mspace lock.
-
- The global lock_ensures that mparams.magic and other unique
- mparams values are initialized only once. It also protects
- sequences of calls to MORECORE. In many cases sys_alloc requires
- two calls, that should not be interleaved with calls by other
- threads. This does not protect against direct calls to MORECORE
- by other threads not using this lock, so there is still code to
- cope the best we can on interference.
-
- Per-mspace locks surround calls to malloc, free, etc.
- By default, locks are simple non-reentrant mutexes.
-
- Because lock-protected regions generally have bounded times, it is
- OK to use the supplied simple spinlocks. Spinlocks are likely to
- improve performance for lightly contended applications, but worsen
- performance under heavy contention.
-
- If USE_LOCKS is > 1, the definitions of lock routines here are
- bypassed, in which case you will need to define the type MLOCK_T,
- and at least INITIAL_LOCK, DESTROY_LOCK, ACQUIRE_LOCK, RELEASE_LOCK
- and TRY_LOCK. You must also declare a
- static MLOCK_T malloc_global_mutex = { initialization values };.
-
-*/
-
-#if !USE_LOCKS
-#define USE_LOCK_BIT (0U)
-#define INITIAL_LOCK(l) (0)
-#define DESTROY_LOCK(l) (0)
-#define ACQUIRE_MALLOC_GLOBAL_LOCK()
-#define RELEASE_MALLOC_GLOBAL_LOCK()
-
-#else
-#if USE_LOCKS > 1
-/* ----------------------- User-defined locks ------------------------ */
-/* Define your own lock implementation here */
-/* #define INITIAL_LOCK(lk) ... */
-/* #define DESTROY_LOCK(lk) ... */
-/* #define ACQUIRE_LOCK(lk) ... */
-/* #define RELEASE_LOCK(lk) ... */
-/* #define TRY_LOCK(lk) ... */
-/* static MLOCK_T malloc_global_mutex = ... */
-
-#define MLOCK_T uint32_t
-#define INITIAL_LOCK(l) (*l = MUTEX_UNLOCKED)
-#define DESTROY_LOCK(l) (0)
-#define ACQUIRE_LOCK(l) (mutex_lock (l))
-#define RELEASE_LOCK(l) (mutex_unlock (l))
-#define TRY_LOCK(l) (mutex_lockE(l))
-static MLOCK_T malloc_global_mutex = MUTEX_UNLOCKED;
-
-#elif USE_SPIN_LOCKS
-
-/* First, define CAS_LOCK and CLEAR_LOCK on ints */
-/* Note CAS_LOCK defined to return 0 on success */
-
-#if defined(__GNUC__)&& (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 1))
-#define CAS_LOCK(sl) __sync_lock_test_and_set(sl, 1)
-#define CLEAR_LOCK(sl) __sync_lock_release(sl)
-
-#elif (defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__)))
-/* Custom spin locks for older gcc on x86 */
-static FORCEINLINE int x86_cas_lock(int *sl) {
- int ret;
- int val = 1;
- int cmp = 0;
- __asm__ __volatile__ ("lock; cmpxchgl %1, %2"
- : "=a" (ret)
- : "r" (val), "m" (*(sl)), "0"(cmp)
- : "memory", "cc");
- return ret;
-}
-
-static FORCEINLINE void x86_clear_lock(int* sl) {
- assert(*sl != 0);
- int prev = 0;
- int ret;
- __asm__ __volatile__ ("lock; xchgl %0, %1"
- : "=r" (ret)
- : "m" (*(sl)), "0"(prev)
- : "memory");
-}
-
-#define CAS_LOCK(sl) x86_cas_lock(sl)
-#define CLEAR_LOCK(sl) x86_clear_lock(sl)
-
-#else /* Win32 MSC */
-#define CAS_LOCK(sl) interlockedexchange(sl, 1)
-#define CLEAR_LOCK(sl) interlockedexchange (sl, 0)
-
-#endif /* ... gcc spins locks ... */
-
-/* How to yield for a spin lock */
-#define SPINS_PER_YIELD 63
-#if defined(_MSC_VER)
-#define SLEEP_EX_DURATION 50 /* delay for yield/sleep */
-#define SPIN_LOCK_YIELD SleepEx(SLEEP_EX_DURATION, FALSE)
-#elif defined (__SVR4) && defined (__sun) /* solaris */
-#define SPIN_LOCK_YIELD thr_yield();
-#elif !defined(LACKS_SCHED_H)
-#define SPIN_LOCK_YIELD sched_yield();
-#else
-#define SPIN_LOCK_YIELD
-#endif /* ... yield ... */
-
-#if !defined(USE_RECURSIVE_LOCKS) || USE_RECURSIVE_LOCKS == 0
-/* Plain spin locks use single word (embedded in malloc_states) */
-static int spin_acquire_lock(int *sl) {
- int spins = 0;
- while (*(volatile int *)sl != 0 || CAS_LOCK(sl)) {
- if ((++spins & SPINS_PER_YIELD) == 0) {
- SPIN_LOCK_YIELD;
- }
- }
- return 0;
-}
-
-#define MLOCK_T int
-#define TRY_LOCK(sl) !CAS_LOCK(sl)
-#define RELEASE_LOCK(sl) CLEAR_LOCK(sl)
-#define ACQUIRE_LOCK(sl) (CAS_LOCK(sl)? spin_acquire_lock(sl) : 0)
-#define INITIAL_LOCK(sl) (*sl = 0)
-#define DESTROY_LOCK(sl) (0)
-static MLOCK_T malloc_global_mutex = 0;
-
-#else /* USE_RECURSIVE_LOCKS */
-/* types for lock owners */
-#ifdef WIN32
-#define THREAD_ID_T DWORD
-#define CURRENT_THREAD GetCurrentThreadId()
-#define EQ_OWNER(X,Y) ((X) == (Y))
-#else
-/*
- Note: the following assume that pthread_t is a type that can be
- initialized to (casted) zero. If this is not the case, you will need to
- somehow redefine these or not use spin locks.
-*/
-#define THREAD_ID_T pthread_t
-#define CURRENT_THREAD pthread_self()
-#define EQ_OWNER(X,Y) pthread_equal(X, Y)
-#endif
-
-struct malloc_recursive_lock {
- int sl;
- unsigned int c;
- THREAD_ID_T threadid;
-};
-
-#define MLOCK_T struct malloc_recursive_lock
-static MLOCK_T malloc_global_mutex = { 0, 0, (THREAD_ID_T)0};
-
-static FORCEINLINE void recursive_release_lock(MLOCK_T *lk) {
- assert(lk->sl != 0);
- if (--lk->c == 0) {
- CLEAR_LOCK(&lk->sl);
- }
-}
-
-static FORCEINLINE int recursive_acquire_lock(MLOCK_T *lk) {
- THREAD_ID_T mythreadid = CURRENT_THREAD;
- int spins = 0;
- for (;;) {
- if (*((volatile int *)(&lk->sl)) == 0) {
- if (!CAS_LOCK(&lk->sl)) {
- lk->threadid = mythreadid;
- lk->c = 1;
- return 0;
- }
- }
- else if (EQ_OWNER(lk->threadid, mythreadid)) {
- ++lk->c;
- return 0;
- }
- if ((++spins & SPINS_PER_YIELD) == 0) {
- SPIN_LOCK_YIELD;
- }
- }
-}
-
-static FORCEINLINE int recursive_try_lock(MLOCK_T *lk) {
- THREAD_ID_T mythreadid = CURRENT_THREAD;
- if (*((volatile int *)(&lk->sl)) == 0) {
- if (!CAS_LOCK(&lk->sl)) {
- lk->threadid = mythreadid;
- lk->c = 1;
- return 1;
- }
- }
- else if (EQ_OWNER(lk->threadid, mythreadid)) {
- ++lk->c;
- return 1;
- }
- return 0;
-}
-
-#define RELEASE_LOCK(lk) recursive_release_lock(lk)
-#define TRY_LOCK(lk) recursive_try_lock(lk)
-#define ACQUIRE_LOCK(lk) recursive_acquire_lock(lk)
-#define INITIAL_LOCK(lk) ((lk)->threadid = (THREAD_ID_T)0, (lk)->sl = 0, (lk)->c = 0)
-#define DESTROY_LOCK(lk) (0)
-#endif /* USE_RECURSIVE_LOCKS */
-
-#elif defined(WIN32) /* Win32 critical sections */
-#define MLOCK_T CRITICAL_SECTION
-#define ACQUIRE_LOCK(lk) (EnterCriticalSection(lk), 0)
-#define RELEASE_LOCK(lk) LeaveCriticalSection(lk)
-#define TRY_LOCK(lk) TryEnterCriticalSection(lk)
-#define INITIAL_LOCK(lk) (!InitializeCriticalSectionAndSpinCount((lk), 0x80000000|4000))
-#define DESTROY_LOCK(lk) (DeleteCriticalSection(lk), 0)
-#define NEED_GLOBAL_LOCK_INIT
-
-static MLOCK_T malloc_global_mutex;
-static volatile long malloc_global_mutex_status;
-
-/* Use spin loop to initialize global lock */
-static void init_malloc_global_mutex() {
- for (;;) {
- long stat = malloc_global_mutex_status;
- if (stat > 0)
- return;
- /* transition to < 0 while initializing, then to > 0) */
- if (stat == 0 &&
- interlockedcompareexchange(&malloc_global_mutex_status, -1, 0) == 0) {
- InitializeCriticalSection(&malloc_global_mutex);
- interlockedexchange(&malloc_global_mutex_status,1);
- return;
- }
- SleepEx(0, FALSE);
- }
-}
-
-#else /* pthreads-based locks */
-#define MLOCK_T pthread_mutex_t
-#define ACQUIRE_LOCK(lk) pthread_mutex_lock(lk)
-#define RELEASE_LOCK(lk) pthread_mutex_unlock(lk)
-#define TRY_LOCK(lk) (!pthread_mutex_trylock(lk))
-#define INITIAL_LOCK(lk) pthread_init_lock(lk)
-#define DESTROY_LOCK(lk) pthread_mutex_destroy(lk)
-
-#if defined(USE_RECURSIVE_LOCKS) && USE_RECURSIVE_LOCKS != 0 && defined(linux) && !defined(PTHREAD_MUTEX_RECURSIVE)
-/* Cope with old-style linux recursive lock initialization by adding */
-/* skipped internal declaration from pthread.h */
-extern int pthread_mutexattr_setkind_np __P ((pthread_mutexattr_t *__attr,
- int __kind));
-#define PTHREAD_MUTEX_RECURSIVE PTHREAD_MUTEX_RECURSIVE_NP
-#define pthread_mutexattr_settype(x,y) pthread_mutexattr_setkind_np(x,y)
-#endif /* USE_RECURSIVE_LOCKS ... */
-
-static MLOCK_T malloc_global_mutex = PTHREAD_MUTEX_INITIALIZER;
-
-static int pthread_init_lock (MLOCK_T *lk) {
- pthread_mutexattr_t attr;
- if (pthread_mutexattr_init(&attr)) return 1;
-#if defined(USE_RECURSIVE_LOCKS) && USE_RECURSIVE_LOCKS != 0
- if (pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE)) return 1;
-#endif
- if (pthread_mutex_init(lk, &attr)) return 1;
- if (pthread_mutexattr_destroy(&attr)) return 1;
- return 0;
-}
-
-#endif /* ... lock types ... */
-
-/* Common code for all lock types */
-#define USE_LOCK_BIT (2U)
-
-#ifndef ACQUIRE_MALLOC_GLOBAL_LOCK
-#define ACQUIRE_MALLOC_GLOBAL_LOCK() ACQUIRE_LOCK(&malloc_global_mutex);
-#endif
-
-#ifndef RELEASE_MALLOC_GLOBAL_LOCK
-#define RELEASE_MALLOC_GLOBAL_LOCK() RELEASE_LOCK(&malloc_global_mutex);
-#endif
-
-#endif /* USE_LOCKS */
-
-/* ----------------------- Chunk representations ------------------------ */
-
-/*
- (The following includes lightly edited explanations by Colin Plumb.)
-
- The malloc_chunk declaration below is misleading (but accurate and
- necessary). It declares a "view" into memory allowing access to
- necessary fields at known offsets from a given base.
-
- Chunks of memory are maintained using a `boundary tag' method as
- originally described by Knuth. (See the paper by Paul Wilson
- ftp://ftp.cs.utexas.edu/pub/garbage/allocsrv.ps for a survey of such
- techniques.) Sizes of free chunks are stored both in the front of
- each chunk and at the end. This makes consolidating fragmented
- chunks into bigger chunks fast. The head fields also hold bits
- representing whether chunks are free or in use.
-
- Here are some pictures to make it clearer. They are "exploded" to
- show that the state of a chunk can be thought of as extending from
- the high 31 bits of the head field of its header through the
- prev_foot and PINUSE_BIT bit of the following chunk header.
-
- A chunk that's in use looks like:
-
- chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Size of previous chunk (if P = 0) |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |P|
- | Size of this chunk 1| +-+
- mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | |
- +- -+
- | |
- +- -+
- | :
- +- size - sizeof(size_t) available payload bytes -+
- : |
- chunk-> +- -+
- | |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |1|
- | Size of next chunk (may or may not be in use) | +-+
- mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-
- And if it's free, it looks like this:
-
- chunk-> +- -+
- | User payload (must be in use, or we would have merged!) |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |P|
- | Size of this chunk 0| +-+
- mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Next pointer |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Prev pointer |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | :
- +- size - sizeof(struct chunk) unused bytes -+
- : |
- chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Size of this chunk |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ |0|
- | Size of next chunk (must be in use, or we would have merged)| +-+
- mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | :
- +- User payload -+
- : |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- |0|
- +-+
- Note that since we always merge adjacent free chunks, the chunks
- adjacent to a free chunk must be in use.
-
- Given a pointer to a chunk (which can be derived trivially from the
- payload pointer) we can, in O(1) time, find out whether the adjacent
- chunks are free, and if so, unlink them from the lists that they
- are on and merge them with the current chunk.
-
- Chunks always begin on even word boundaries, so the mem portion
- (which is returned to the user) is also on an even word boundary, and
- thus at least double-word aligned.
-
- The P (PINUSE_BIT) bit, stored in the unused low-order bit of the
- chunk size (which is always a multiple of two words), is an in-use
- bit for the *previous* chunk. If that bit is *clear*, then the
- word before the current chunk size contains the previous chunk
- size, and can be used to find the front of the previous chunk.
- The very first chunk allocated always has this bit set, preventing
- access to non-existent (or non-owned) memory. If pinuse is set for
- any given chunk, then you CANNOT determine the size of the
- previous chunk, and might even get a memory addressing fault when
- trying to do so.
-
- The C (CINUSE_BIT) bit, stored in the unused second-lowest bit of
- the chunk size redundantly records whether the current chunk is
- inuse (unless the chunk is mmapped). This redundancy enables usage
- checks within free and realloc, and reduces indirection when freeing
- and consolidating chunks.
-
- Each freshly allocated chunk must have both cinuse and pinuse set.
- That is, each allocated chunk borders either a previously allocated
- and still in-use chunk, or the base of its memory arena. This is
- ensured by making all allocations from the `lowest' part of any
- found chunk. Further, no free chunk physically borders another one,
- so each free chunk is known to be preceded and followed by either
- inuse chunks or the ends of memory.
-
- Note that the `foot' of the current chunk is actually represented
- as the prev_foot of the NEXT chunk. This makes it easier to
- deal with alignments etc but can be very confusing when trying
- to extend or adapt this code.
-
- The exceptions to all this are
-
- 1. The special chunk `top' is the top-most available chunk (i.e.,
- the one bordering the end of available memory). It is treated
- specially. Top is never included in any bin, is used only if
- no other chunk is available, and is released back to the
- system if it is very large (see M_TRIM_THRESHOLD). In effect,
- the top chunk is treated as larger (and thus less well
- fitting) than any other available chunk. The top chunk
- doesn't update its trailing size field since there is no next
- contiguous chunk that would have to index off it. However,
- space is still allocated for it (TOP_FOOT_SIZE) to enable
- separation or merging when space is extended.
-
- 3. Chunks allocated via mmap, have both cinuse and pinuse bits
- cleared in their head fields. Because they are allocated
- one-by-one, each must carry its own prev_foot field, which is
- also used to hold the offset this chunk has within its mmapped
- region, which is needed to preserve alignment. Each mmapped
- chunk is trailed by the first two fields of a fake next-chunk
- for sake of usage checks.
-
-*/
-
-struct malloc_chunk {
- size_t prev_foot; /* Size of previous chunk (if free). */
- size_t head; /* Size and inuse bits. */
- struct malloc_chunk* fd; /* double links -- used only if free. */
- struct malloc_chunk* bk;
-};
-
-typedef struct malloc_chunk mchunk;
-typedef struct malloc_chunk* mchunkptr;
-typedef struct malloc_chunk* sbinptr; /* The type of bins of chunks */
-typedef unsigned int bindex_t; /* Described below */
-typedef unsigned int binmap_t; /* Described below */
-typedef unsigned int flag_t; /* The type of various bit flag sets */
-
-/* ------------------- Chunks sizes and alignments ----------------------- */
-
-#define MCHUNK_SIZE (sizeof(mchunk))
-
-#if FOOTERS
-#define CHUNK_OVERHEAD (TWO_SIZE_T_SIZES)
-#else /* FOOTERS */
-#define CHUNK_OVERHEAD (SIZE_T_SIZE)
-#endif /* FOOTERS */
-
-/* MMapped chunks need a second word of overhead ... */
-#define MMAP_CHUNK_OVERHEAD (TWO_SIZE_T_SIZES)
-/* ... and additional padding for fake next-chunk at foot */
-#define MMAP_FOOT_PAD (FOUR_SIZE_T_SIZES)
-
-/* The smallest size we can malloc is an aligned minimal chunk */
-#define MIN_CHUNK_SIZE\
- ((MCHUNK_SIZE + CHUNK_ALIGN_MASK) & ~CHUNK_ALIGN_MASK)
-
-/* conversion from malloc headers to user pointers, and back */
-#define chunk2mem(p) ((void*)((char*)(p) + TWO_SIZE_T_SIZES))
-#define mem2chunk(mem) ((mchunkptr)((char*)(mem) - TWO_SIZE_T_SIZES))
-/* chunk associated with aligned address A */
-#define align_as_chunk(A) (mchunkptr)((A) + align_offset(chunk2mem(A)))
-
-/* Bounds on request (not chunk) sizes. */
-#define MAX_REQUEST ((-MIN_CHUNK_SIZE) << 2)
-#define MIN_REQUEST (MIN_CHUNK_SIZE - CHUNK_OVERHEAD - SIZE_T_ONE)
-
-/* pad request bytes into a usable size */
-#define pad_request(req) \
- (((req) + CHUNK_OVERHEAD + CHUNK_ALIGN_MASK) & ~CHUNK_ALIGN_MASK)
-
-/* pad request, checking for minimum (but not maximum) */
-#define request2size(req) \
- (((req) < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(req))
-
-
-/* ------------------ Operations on head and foot fields ----------------- */
-
-/*
- The head field of a chunk is or'ed with PINUSE_BIT when previous
- adjacent chunk in use, and or'ed with CINUSE_BIT if this chunk is in
- use, unless mmapped, in which case both bits are cleared.
-
- FLAG4_BIT is not used by this malloc, but might be useful in extensions.
-*/
-
-#define PINUSE_BIT (SIZE_T_ONE)
-#define CINUSE_BIT (SIZE_T_TWO)
-#define FLAG4_BIT (SIZE_T_FOUR)
-#define INUSE_BITS (PINUSE_BIT|CINUSE_BIT)
-#define FLAG_BITS (PINUSE_BIT|CINUSE_BIT|FLAG4_BIT)
-
-/* Head value for fenceposts */
-#define FENCEPOST_HEAD (INUSE_BITS|SIZE_T_SIZE)
-
-/* extraction of fields from head words */
-#define cinuse(p) ((p)->head & CINUSE_BIT)
-#define pinuse(p) ((p)->head & PINUSE_BIT)
-#define flag4inuse(p) ((p)->head & FLAG4_BIT)
-#define is_inuse(p) (((p)->head & INUSE_BITS) != PINUSE_BIT)
-#define is_mmapped(p) (((p)->head & INUSE_BITS) == 0)
-
-#define chunksize(p) ((p)->head & ~(FLAG_BITS))
-
-#define clear_pinuse(p) ((p)->head &= ~PINUSE_BIT)
-#define set_flag4(p) ((p)->head |= FLAG4_BIT)
-#define clear_flag4(p) ((p)->head &= ~FLAG4_BIT)
-
-/* Treat space at ptr +/- offset as a chunk */
-#define chunk_plus_offset(p, s) ((mchunkptr)(((char*)(p)) + (s)))
-#define chunk_minus_offset(p, s) ((mchunkptr)(((char*)(p)) - (s)))
-
-/* Ptr to next or previous physical malloc_chunk. */
-#define next_chunk(p) ((mchunkptr)( ((char*)(p)) + ((p)->head & ~FLAG_BITS)))
-#define prev_chunk(p) ((mchunkptr)( ((char*)(p)) - ((p)->prev_foot) ))
-
-/* extract next chunk's pinuse bit */
-#define next_pinuse(p) ((next_chunk(p)->head) & PINUSE_BIT)
-
-/* Get/set size at footer */
-#define get_foot(p, s) (((mchunkptr)((char*)(p) + (s)))->prev_foot)
-#define set_foot(p, s) (((mchunkptr)((char*)(p) + (s)))->prev_foot = (s))
-
-/* Set size, pinuse bit, and foot */
-#define set_size_and_pinuse_of_free_chunk(p, s)\
- ((p)->head = (s|PINUSE_BIT), set_foot(p, s))
-
-/* Set size, pinuse bit, foot, and clear next pinuse */
-#define set_free_with_pinuse(p, s, n)\
- (clear_pinuse(n), set_size_and_pinuse_of_free_chunk(p, s))
-
-/* Get the internal overhead associated with chunk p */
-#define overhead_for(p)\
- (is_mmapped(p)? MMAP_CHUNK_OVERHEAD : CHUNK_OVERHEAD)
-
-/* Return true if malloced space is not necessarily cleared */
-#if MMAP_CLEARS
-#define calloc_must_clear(p) (!is_mmapped(p))
-#else /* MMAP_CLEARS */
-#define calloc_must_clear(p) (1)
-#endif /* MMAP_CLEARS */
-
-/* ---------------------- Overlaid data structures ----------------------- */
-
-/*
- When chunks are not in use, they are treated as nodes of either
- lists or trees.
-
- "Small" chunks are stored in circular doubly-linked lists, and look
- like this:
-
- chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Size of previous chunk |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- `head:' | Size of chunk, in bytes |P|
- mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Forward pointer to next chunk in list |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Back pointer to previous chunk in list |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Unused space (may be 0 bytes long) .
- . .
- . |
-nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- `foot:' | Size of chunk, in bytes |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-
- Larger chunks are kept in a form of bitwise digital trees (aka
- tries) keyed on chunksizes. Because malloc_tree_chunks are only for
- free chunks greater than 256 bytes, their size doesn't impose any
- constraints on user chunk sizes. Each node looks like:
-
- chunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Size of previous chunk |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- `head:' | Size of chunk, in bytes |P|
- mem-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Forward pointer to next chunk of same size |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Back pointer to previous chunk of same size |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Pointer to left child (child[0]) |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Pointer to right child (child[1]) |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Pointer to parent |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | bin index of this chunk |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- | Unused space .
- . |
-nextchunk-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- `foot:' | Size of chunk, in bytes |
- +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
-
- Each tree holding treenodes is a tree of unique chunk sizes. Chunks
- of the same size are arranged in a circularly-linked list, with only
- the oldest chunk (the next to be used, in our FIFO ordering)
- actually in the tree. (Tree members are distinguished by a non-null
- parent pointer.) If a chunk with the same size an an existing node
- is inserted, it is linked off the existing node using pointers that
- work in the same way as fd/bk pointers of small chunks.
-
- Each tree contains a power of 2 sized range of chunk sizes (the
- smallest is 0x100 <= x < 0x180), which is is divided in half at each
- tree level, with the chunks in the smaller half of the range (0x100
- <= x < 0x140 for the top nose) in the left subtree and the larger
- half (0x140 <= x < 0x180) in the right subtree. This is, of course,
- done by inspecting individual bits.
-
- Using these rules, each node's left subtree contains all smaller
- sizes than its right subtree. However, the node at the root of each
- subtree has no particular ordering relationship to either. (The
- dividing line between the subtree sizes is based on trie relation.)
- If we remove the last chunk of a given size from the interior of the
- tree, we need to replace it with a leaf node. The tree ordering
- rules permit a node to be replaced by any leaf below it.
-
- The smallest chunk in a tree (a common operation in a best-fit
- allocator) can be found by walking a path to the leftmost leaf in
- the tree. Unlike a usual binary tree, where we follow left child
- pointers until we reach a null, here we follow the right child
- pointer any time the left one is null, until we reach a leaf with
- both child pointers null. The smallest chunk in the tree will be
- somewhere along that path.
-
- The worst case number of steps to add, find, or remove a node is
- bounded by the number of bits differentiating chunks within
- bins. Under current bin calculations, this ranges from 6 up to 21
- (for 32 bit sizes) or up to 53 (for 64 bit sizes). The typical case
- is of course much better.
-*/
-
-struct malloc_tree_chunk {
- /* The first four fields must be compatible with malloc_chunk */
- size_t prev_foot;
- size_t head;
- struct malloc_tree_chunk* fd;
- struct malloc_tree_chunk* bk;
-
- struct malloc_tree_chunk* child[2];
- struct malloc_tree_chunk* parent;
- bindex_t index;
-};
-
-typedef struct malloc_tree_chunk tchunk;
-typedef struct malloc_tree_chunk* tchunkptr;
-typedef struct malloc_tree_chunk* tbinptr; /* The type of bins of trees */
-
-/* A little helper macro for trees */
-#define leftmost_child(t) ((t)->child[0] != 0? (t)->child[0] : (t)->child[1])
-
-/* ----------------------------- Segments -------------------------------- */
-
-/*
- Each malloc space may include non-contiguous segments, held in a
- list headed by an embedded malloc_segment record representing the
- top-most space. Segments also include flags holding properties of
- the space. Large chunks that are directly allocated by mmap are not
- included in this list. They are instead independently created and
- destroyed without otherwise keeping track of them.
-
- Segment management mainly comes into play for spaces allocated by
- MMAP. Any call to MMAP might or might not return memory that is
- adjacent to an existing segment. MORECORE normally contiguously
- extends the current space, so this space is almost always adjacent,
- which is simpler and faster to deal with. (This is why MORECORE is
- used preferentially to MMAP when both are available -- see
- sys_alloc.) When allocating using MMAP, we don't use any of the
- hinting mechanisms (inconsistently) supported in various
- implementations of unix mmap, or distinguish reserving from
- committing memory. Instead, we just ask for space, and exploit
- contiguity when we get it. It is probably possible to do
- better than this on some systems, but no general scheme seems
- to be significantly better.
-
- Management entails a simpler variant of the consolidation scheme
- used for chunks to reduce fragmentation -- new adjacent memory is
- normally prepended or appended to an existing segment. However,
- there are limitations compared to chunk consolidation that mostly
- reflect the fact that segment processing is relatively infrequent
- (occurring only when getting memory from system) and that we
- don't expect to have huge numbers of segments:
-
- * Segments are not indexed, so traversal requires linear scans. (It
- would be possible to index these, but is not worth the extra
- overhead and complexity for most programs on most platforms.)
- * New segments are only appended to old ones when holding top-most
- memory; if they cannot be prepended to others, they are held in
- different segments.
-
- Except for the top-most segment of an mstate, each segment record
- is kept at the tail of its segment. Segments are added by pushing
- segment records onto the list headed by &mstate.seg for the
- containing mstate.
-
- Segment flags control allocation/merge/deallocation policies:
- * If EXTERN_BIT set, then we did not allocate this segment,
- and so should not try to deallocate or merge with others.
- (This currently holds only for the initial segment passed
- into create_mspace_with_base.)
- * If USE_MMAP_BIT set, the segment may be merged with
- other surrounding mmapped segments and trimmed/de-allocated
- using munmap.
- * If neither bit is set, then the segment was obtained using
- MORECORE so can be merged with surrounding MORECORE'd segments
- and deallocated/trimmed using MORECORE with negative arguments.
-*/
-
-struct malloc_segment {
- char* base; /* base address */
- size_t size; /* allocated size */
- struct malloc_segment* next; /* ptr to next segment */
- flag_t sflags; /* mmap and extern flag */
-};
-
-#define is_mmapped_segment(S) ((S)->sflags & USE_MMAP_BIT)
-#define is_extern_segment(S) ((S)->sflags & EXTERN_BIT)
-
-typedef struct malloc_segment msegment;
-typedef struct malloc_segment* msegmentptr;
-
-/* ---------------------------- malloc_state ----------------------------- */
-
-/*
- A malloc_state holds all of the bookkeeping for a space.
- The main fields are:
-
- Top
- The topmost chunk of the currently active segment. Its size is
- cached in topsize. The actual size of topmost space is
- topsize+TOP_FOOT_SIZE, which includes space reserved for adding
- fenceposts and segment records if necessary when getting more
- space from the system. The size at which to autotrim top is
- cached from mparams in trim_check, except that it is disabled if
- an autotrim fails.
-
- Designated victim (dv)
- This is the preferred chunk for servicing small requests that
- don't have exact fits. It is normally the chunk split off most
- recently to service another small request. Its size is cached in
- dvsize. The link fields of this chunk are not maintained since it
- is not kept in a bin.
-
- SmallBins
- An array of bin headers for free chunks. These bins hold chunks
- with sizes less than MIN_LARGE_SIZE bytes. Each bin contains
- chunks of all the same size, spaced 8 bytes apart. To simplify
- use in double-linked lists, each bin header acts as a malloc_chunk
- pointing to the real first node, if it exists (else pointing to
- itself). This avoids special-casing for headers. But to avoid
- waste, we allocate only the fd/bk pointers of bins, and then use
- repositioning tricks to treat these as the fields of a chunk.
-
- TreeBins
- Treebins are pointers to the roots of trees holding a range of
- sizes. There are 2 equally spaced treebins for each power of two
- from TREE_SHIFT to TREE_SHIFT+16. The last bin holds anything
- larger.
-
- Bin maps
- There is one bit map for small bins ("smallmap") and one for
- treebins ("treemap). Each bin sets its bit when non-empty, and
- clears the bit when empty. Bit operations are then used to avoid
- bin-by-bin searching -- nearly all "search" is done without ever
- looking at bins that won't be selected. The bit maps
- conservatively use 32 bits per map word, even if on 64bit system.
- For a good description of some of the bit-based techniques used
- here, see Henry S. Warren Jr's book "Hacker's Delight" (and
- supplement at http://hackersdelight.org/). Many of these are
- intended to reduce the branchiness of paths through malloc etc, as
- well as to reduce the number of memory locations read or written.
-
- Segments
- A list of segments headed by an embedded malloc_segment record
- representing the initial space.
-
- Address check support
- The least_addr field is the least address ever obtained from
- MORECORE or MMAP. Attempted frees and reallocs of any address less
- than this are trapped (unless INSECURE is defined).
-
- Magic tag
- A cross-check field that should always hold same value as mparams.magic.
-
- Max allowed footprint
- The maximum allowed bytes to allocate from system (zero means no limit)
-
- Flags
- Bits recording whether to use MMAP, locks, or contiguous MORECORE
-
- Statistics
- Each space keeps track of current and maximum system memory
- obtained via MORECORE or MMAP.
-
- Trim support
- Fields holding the amount of unused topmost memory that should trigger
- trimming, and a counter to force periodic scanning to release unused
- non-topmost segments.
-
- Locking
- If USE_LOCKS is defined, the "mutex" lock is acquired and released
- around every public call using this mspace.
-
- Extension support
- A void* pointer and a size_t field that can be used to help implement
- extensions to this malloc.
-*/
-
-/* Bin types, widths and sizes */
-#define NSMALLBINS (32U)
-#define NTREEBINS (32U)
-#define SMALLBIN_SHIFT (3U)
-#define SMALLBIN_WIDTH (SIZE_T_ONE << SMALLBIN_SHIFT)
-#define TREEBIN_SHIFT (8U)
-#define MIN_LARGE_SIZE (SIZE_T_ONE << TREEBIN_SHIFT)
-#define MAX_SMALL_SIZE (MIN_LARGE_SIZE - SIZE_T_ONE)
-#define MAX_SMALL_REQUEST (MAX_SMALL_SIZE - CHUNK_ALIGN_MASK - CHUNK_OVERHEAD)
-
-struct malloc_state {
- binmap_t smallmap;
- binmap_t treemap;
- size_t dvsize;
- size_t topsize;
- char* least_addr;
- mchunkptr dv;
- mchunkptr top;
- size_t trim_check;
- size_t release_checks;
- size_t magic;
- mchunkptr smallbins[(NSMALLBINS+1)*2];
- tbinptr treebins[NTREEBINS];
- size_t footprint;
- size_t max_footprint;
- size_t footprint_limit; /* zero means no limit */
- flag_t mflags;
-#if USE_LOCKS
- MLOCK_T mutex; /* locate lock among fields that rarely change */
-#endif /* USE_LOCKS */
- msegment seg;
- void* extp; /* Unused but available for extensions */
- size_t exts;
-};
-
-typedef struct malloc_state* mstate;
-
-/* ------------- Global malloc_state and malloc_params ------------------- */
-
-/*
- malloc_params holds global properties, including those that can be
- dynamically set using mallopt. There is a single instance, mparams,
- initialized in init_mparams. Note that the non-zeroness of "magic"
- also serves as an initialization flag.
-*/
-
-struct malloc_params {
- size_t magic;
- size_t page_size;
- size_t granularity;
- size_t mmap_threshold;
- size_t trim_threshold;
- flag_t default_mflags;
-};
-
-static struct malloc_params mparams;
-
-/* Ensure mparams initialized */
-#define ensure_initialization() (void)(mparams.magic != 0 || init_mparams())
-
-#if !ONLY_MSPACES
-
-/* The global malloc_state used for all non-"mspace" calls */
-static struct malloc_state _gm_;
-#define gm (&_gm_)
-#define is_global(M) ((M) == &_gm_)
-
-#endif /* !ONLY_MSPACES */
-
-#define is_initialized(M) ((M)->top != 0)
-
-/* -------------------------- system alloc setup ------------------------- */
-
-/* Operations on mflags */
-
-#define use_lock(M) ((M)->mflags & USE_LOCK_BIT)
-#define enable_lock(M) ((M)->mflags |= USE_LOCK_BIT)
-#if USE_LOCKS
-#define disable_lock(M) ((M)->mflags &= ~USE_LOCK_BIT)
-#else
-#define disable_lock(M)
-#endif
-
-#define use_mmap(M) ((M)->mflags & USE_MMAP_BIT)
-#define enable_mmap(M) ((M)->mflags |= USE_MMAP_BIT)
-#if HAVE_MMAP
-#define disable_mmap(M) ((M)->mflags &= ~USE_MMAP_BIT)
-#else
-#define disable_mmap(M)
-#endif
-
-#define use_noncontiguous(M) ((M)->mflags & USE_NONCONTIGUOUS_BIT)
-#define disable_contiguous(M) ((M)->mflags |= USE_NONCONTIGUOUS_BIT)
-
-#define set_lock(M,L)\
- ((M)->mflags = (L)?\
- ((M)->mflags | USE_LOCK_BIT) :\
- ((M)->mflags & ~USE_LOCK_BIT))
-
-/* page-align a size */
-#define page_align(S)\
- (((S) + (mparams.page_size - SIZE_T_ONE)) & ~(mparams.page_size - SIZE_T_ONE))
-
-/* granularity-align a size */
-#define granularity_align(S)\
- (((S) + (mparams.granularity - SIZE_T_ONE))\
- & ~(mparams.granularity - SIZE_T_ONE))
-
-
-/* For mmap, use granularity alignment on windows, else page-align */
-#ifdef WIN32
-#define mmap_align(S) granularity_align(S)
-#else
-#define mmap_align(S) page_align(S)
-#endif
-
-/* For sys_alloc, enough padding to ensure can malloc request on success */
-#define SYS_ALLOC_PADDING (TOP_FOOT_SIZE + MALLOC_ALIGNMENT)
-
-#define is_page_aligned(S)\
- (((size_t)(S) & (mparams.page_size - SIZE_T_ONE)) == 0)
-#define is_granularity_aligned(S)\
- (((size_t)(S) & (mparams.granularity - SIZE_T_ONE)) == 0)
-
-/* True if segment S holds address A */
-#define segment_holds(S, A)\
- ((char*)(A) >= S->base && (char*)(A) < S->base + S->size)
-
-/* Return segment holding given address */
-static msegmentptr segment_holding(mstate m, char* addr) {
- msegmentptr sp = &m->seg;
- for (;;) {
- if (addr >= sp->base && addr < sp->base + sp->size)
- return sp;
- if ((sp = sp->next) == 0)
- return 0;
- }
-}
-
-/* Return true if segment contains a segment link */
-static int has_segment_link(mstate m, msegmentptr ss) {
- msegmentptr sp = &m->seg;
- for (;;) {
- if ((char*)sp >= ss->base && (char*)sp < ss->base + ss->size)
- return 1;
- if ((sp = sp->next) == 0)
- return 0;
- }
-}
-
-#ifndef MORECORE_CANNOT_TRIM
-#define should_trim(M,s) ((s) > (M)->trim_check)
-#else /* MORECORE_CANNOT_TRIM */
-#define should_trim(M,s) (0)
-#endif /* MORECORE_CANNOT_TRIM */
-
-/*
- TOP_FOOT_SIZE is padding at the end of a segment, including space
- that may be needed to place segment records and fenceposts when new
- noncontiguous segments are added.
-*/
-#define TOP_FOOT_SIZE\
- (align_offset(chunk2mem(0))+pad_request(sizeof(struct malloc_segment))+MIN_CHUNK_SIZE)
-
-
-/* ------------------------------- Hooks -------------------------------- */
-
-/*
- PREACTION should be defined to return 0 on success, and nonzero on
- failure. If you are not using locking, you can redefine these to do
- anything you like.
-*/
-
-#if USE_LOCKS
-#define PREACTION(M) ((use_lock(M))? ACQUIRE_LOCK(&(M)->mutex) : 0)
-#define POSTACTION(M) { if (use_lock(M)) RELEASE_LOCK(&(M)->mutex); }
-#else /* USE_LOCKS */
-
-#ifndef PREACTION
-#define PREACTION(M) (0)
-#endif /* PREACTION */
-
-#ifndef POSTACTION
-#define POSTACTION(M)
-#endif /* POSTACTION */
-
-#endif /* USE_LOCKS */
-
-/*
- CORRUPTION_ERROR_ACTION is triggered upon detected bad addresses.
- USAGE_ERROR_ACTION is triggered on detected bad frees and
- reallocs. The argument p is an address that might have triggered the
- fault. It is ignored by the two predefined actions, but might be
- useful in custom actions that try to help diagnose errors.
-*/
-
-#if PROCEED_ON_ERROR
-
-/* A count of the number of corruption errors causing resets */
-int malloc_corruption_error_count;
-
-/* default corruption action */
-static void reset_on_error(mstate m);
-
-#define CORRUPTION_ERROR_ACTION(m) reset_on_error(m)
-#define USAGE_ERROR_ACTION(m, p)
-
-#else /* PROCEED_ON_ERROR */
-
-#ifndef CORRUPTION_ERROR_ACTION
-#define CORRUPTION_ERROR_ACTION(m) ABORT
-#endif /* CORRUPTION_ERROR_ACTION */
-
-#ifndef USAGE_ERROR_ACTION
-#define USAGE_ERROR_ACTION(m,p) ABORT
-#endif /* USAGE_ERROR_ACTION */
-
-#endif /* PROCEED_ON_ERROR */
-
-
-/* -------------------------- Debugging setup ---------------------------- */
-
-#if ! DEBUG
-
-#define check_free_chunk(M,P)
-#define check_inuse_chunk(M,P)
-#define check_malloced_chunk(M,P,N)
-#define check_mmapped_chunk(M,P)
-#define check_malloc_state(M)
-#define check_top_chunk(M,P)
-
-#else /* DEBUG */
-#define check_free_chunk(M,P) do_check_free_chunk(M,P)
-#define check_inuse_chunk(M,P) do_check_inuse_chunk(M,P)
-#define check_top_chunk(M,P) do_check_top_chunk(M,P)
-#define check_malloced_chunk(M,P,N) do_check_malloced_chunk(M,P,N)
-#define check_mmapped_chunk(M,P) do_check_mmapped_chunk(M,P)
-#define check_malloc_state(M) do_check_malloc_state(M)
-
-static void do_check_any_chunk(mstate m, mchunkptr p);
-static void do_check_top_chunk(mstate m, mchunkptr p);
-static void do_check_mmapped_chunk(mstate m, mchunkptr p);
-static void do_check_inuse_chunk(mstate m, mchunkptr p);
-static void do_check_free_chunk(mstate m, mchunkptr p);
-static void do_check_malloced_chunk(mstate m, void* mem, size_t s);
-static void do_check_tree(mstate m, tchunkptr t);
-static void do_check_treebin(mstate m, bindex_t i);
-static void do_check_smallbin(mstate m, bindex_t i);
-static void do_check_malloc_state(mstate m);
-static int bin_find(mstate m, mchunkptr x);
-static size_t traverse_and_check(mstate m);
-#endif /* DEBUG */
-
-/* ---------------------------- Indexing Bins ---------------------------- */
-
-#define is_small(s) (((s) >> SMALLBIN_SHIFT) < NSMALLBINS)
-#define small_index(s) (bindex_t)((s) >> SMALLBIN_SHIFT)
-#define small_index2size(i) ((i) << SMALLBIN_SHIFT)
-#define MIN_SMALL_INDEX (small_index(MIN_CHUNK_SIZE))
-
-/* addressing by index. See above about smallbin repositioning */
-#define smallbin_at(M, i) ((sbinptr)((char*)&((M)->smallbins[(i)<<1])))
-#define treebin_at(M,i) (&((M)->treebins[i]))
-
-/* assign tree index for size S to variable I. Use x86 asm if possible */
-#if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
-#define compute_tree_index(S, I)\
-{\
- unsigned int X = S >> TREEBIN_SHIFT;\
- if (X == 0)\
- I = 0;\
- else if (X > 0xFFFF)\
- I = NTREEBINS-1;\
- else {\
- unsigned int K = (unsigned) sizeof(X)*__CHAR_BIT__ - 1 - (unsigned) __builtin_clz(X); \
- I = (bindex_t)((K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1)));\
- }\
-}
-
-#elif defined (__INTEL_COMPILER)
-#define compute_tree_index(S, I)\
-{\
- size_t X = S >> TREEBIN_SHIFT;\
- if (X == 0)\
- I = 0;\
- else if (X > 0xFFFF)\
- I = NTREEBINS-1;\
- else {\
- unsigned int K = _bit_scan_reverse (X); \
- I = (bindex_t)((K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1)));\
- }\
-}
-
-#elif defined(_MSC_VER) && _MSC_VER>=1300
-#define compute_tree_index(S, I)\
-{\
- size_t X = S >> TREEBIN_SHIFT;\
- if (X == 0)\
- I = 0;\
- else if (X > 0xFFFF)\
- I = NTREEBINS-1;\
- else {\
- unsigned int K;\
- _BitScanReverse((DWORD *) &K, (DWORD) X);\
- I = (bindex_t)((K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1)));\
- }\
-}
-
-#else /* GNUC */
-#define compute_tree_index(S, I)\
-{\
- size_t X = S >> TREEBIN_SHIFT;\
- if (X == 0)\
- I = 0;\
- else if (X > 0xFFFF)\
- I = NTREEBINS-1;\
- else {\
- unsigned int Y = (unsigned int)X;\
- unsigned int N = ((Y - 0x100) >> 16) & 8;\
- unsigned int K = (((Y <<= N) - 0x1000) >> 16) & 4;\
- N += K;\
- N += K = (((Y <<= K) - 0x4000) >> 16) & 2;\
- K = 14 - N + ((Y <<= K) >> 15);\
- I = (K << 1) + ((S >> (K + (TREEBIN_SHIFT-1)) & 1));\
- }\
-}
-#endif /* GNUC */
-
-/* Bit representing maximum resolved size in a treebin at i */
-#define bit_for_tree_index(i) \
- (i == NTREEBINS-1)? (SIZE_T_BITSIZE-1) : (((i) >> 1) + TREEBIN_SHIFT - 2)
-
-/* Shift placing maximum resolved bit in a treebin at i as sign bit */
-#define leftshift_for_tree_index(i) \
- ((i == NTREEBINS-1)? 0 : \
- ((SIZE_T_BITSIZE-SIZE_T_ONE) - (((i) >> 1) + TREEBIN_SHIFT - 2)))
-
-/* The size of the smallest chunk held in bin with index i */
-#define minsize_for_tree_index(i) \
- ((SIZE_T_ONE << (((i) >> 1) + TREEBIN_SHIFT)) | \
- (((size_t)((i) & SIZE_T_ONE)) << (((i) >> 1) + TREEBIN_SHIFT - 1)))
-
-
-/* ------------------------ Operations on bin maps ----------------------- */
-
-/* bit corresponding to given index */
-#define idx2bit(i) ((binmap_t)(1) << (i))
-
-/* Mark/Clear bits with given index */
-#define mark_smallmap(M,i) ((M)->smallmap |= idx2bit(i))
-#define clear_smallmap(M,i) ((M)->smallmap &= ~idx2bit(i))
-#define smallmap_is_marked(M,i) ((M)->smallmap & idx2bit(i))
-
-#define mark_treemap(M,i) ((M)->treemap |= idx2bit(i))
-#define clear_treemap(M,i) ((M)->treemap &= ~idx2bit(i))
-#define treemap_is_marked(M,i) ((M)->treemap & idx2bit(i))
-
-/* isolate the least set bit of a bitmap */
-#define least_bit(x) ((x) & -(x))
-
-/* mask with all bits to left of least bit of x on */
-#define left_bits(x) ((x<<1) | -(x<<1))
-
-/* mask with all bits to left of or equal to least bit of x on */
-#define same_or_left_bits(x) ((x) | -(x))
-
-/* index corresponding to given bit. Use x86 asm if possible */
-
-#if defined(__GNUC__) && (defined(__i386__) || defined(__x86_64__))
-#define compute_bit2idx(X, I)\
-{\
- unsigned int J;\
- J = __builtin_ctz(X); \
- I = (bindex_t)J;\
-}
-
-#elif defined (__INTEL_COMPILER)
-#define compute_bit2idx(X, I)\
-{\
- unsigned int J;\
- J = _bit_scan_forward (X); \
- I = (bindex_t)J;\
-}
-
-#elif defined(_MSC_VER) && _MSC_VER>=1300
-#define compute_bit2idx(X, I)\
-{\
- unsigned int J;\
- _BitScanForward((DWORD *) &J, X);\
- I = (bindex_t)J;\
-}
-
-#elif USE_BUILTIN_FFS
-#define compute_bit2idx(X, I) I = ffs(X)-1
-
-#else
-#define compute_bit2idx(X, I)\
-{\
- unsigned int Y = X - 1;\
- unsigned int K = Y >> (16-4) & 16;\
- unsigned int N = K; Y >>= K;\
- N += K = Y >> (8-3) & 8; Y >>= K;\
- N += K = Y >> (4-2) & 4; Y >>= K;\
- N += K = Y >> (2-1) & 2; Y >>= K;\
- N += K = Y >> (1-0) & 1; Y >>= K;\
- I = (bindex_t)(N + Y);\
-}
-#endif /* GNUC */
-
-
-/* ----------------------- Runtime Check Support ------------------------- */
-
-/*
- For security, the main invariant is that malloc/free/etc never
- writes to a static address other than malloc_state, unless static
- malloc_state itself has been corrupted, which cannot occur via
- malloc (because of these checks). In essence this means that we
- believe all pointers, sizes, maps etc held in malloc_state, but
- check all of those linked or offsetted from other embedded data
- structures. These checks are interspersed with main code in a way
- that tends to minimize their run-time cost.
-
- When FOOTERS is defined, in addition to range checking, we also
- verify footer fields of inuse chunks, which can be used guarantee
- that the mstate controlling malloc/free is intact. This is a
- streamlined version of the approach described by William Robertson
- et al in "Run-time Detection of Heap-based Overflows" LISA'03
- http://www.usenix.org/events/lisa03/tech/robertson.html The footer
- of an inuse chunk holds the xor of its mstate and a random seed,
- that is checked upon calls to free() and realloc(). This is
- (probabalistically) unguessable from outside the program, but can be
- computed by any code successfully malloc'ing any chunk, so does not
- itself provide protection against code that has already broken
- security through some other means. Unlike Robertson et al, we
- always dynamically check addresses of all offset chunks (previous,
- next, etc). This turns out to be cheaper than relying on hashes.
-*/
-
-#if !INSECURE
-/* Check if address a is at least as high as any from MORECORE or MMAP */
-#define ok_address(M, a) ((char*)(a) >= (M)->least_addr)
-/* Check if address of next chunk n is higher than base chunk p */
-#define ok_next(p, n) ((char*)(p) < (char*)(n))
-/* Check if p has inuse status */
-#define ok_inuse(p) is_inuse(p)
-/* Check if p has its pinuse bit on */
-#define ok_pinuse(p) pinuse(p)
-
-#else /* !INSECURE */
-#define ok_address(M, a) (1)
-#define ok_next(b, n) (1)
-#define ok_inuse(p) (1)
-#define ok_pinuse(p) (1)
-#endif /* !INSECURE */
-
-#if (FOOTERS && !INSECURE)
-/* Check if (alleged) mstate m has expected magic field */
-#define ok_magic(M) ((M)->magic == mparams.magic)
-#else /* (FOOTERS && !INSECURE) */
-#define ok_magic(M) (1)
-#endif /* (FOOTERS && !INSECURE) */
-
-/* In gcc, use __builtin_expect to minimize impact of checks */
-#if !INSECURE
-#if defined(__GNUC__) && __GNUC__ >= 3
-#define RTCHECK(e) __builtin_expect(e, 1)
-#else /* GNUC */
-#define RTCHECK(e) (e)
-#endif /* GNUC */
-#else /* !INSECURE */
-#define RTCHECK(e) (1)
-#endif /* !INSECURE */
-
-/* macros to set up inuse chunks with or without footers */
-
-#if !FOOTERS
-
-#define mark_inuse_foot(M,p,s)
-
-/* Macros for setting head/foot of non-mmapped chunks */
-
-/* Set cinuse bit and pinuse bit of next chunk */
-#define set_inuse(M,p,s)\
- ((p)->head = (((p)->head & PINUSE_BIT)|s|CINUSE_BIT),\
- ((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT)
-
-/* Set cinuse and pinuse of this chunk and pinuse of next chunk */
-#define set_inuse_and_pinuse(M,p,s)\
- ((p)->head = (s|PINUSE_BIT|CINUSE_BIT),\
- ((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT)
-
-/* Set size, cinuse and pinuse bit of this chunk */
-#define set_size_and_pinuse_of_inuse_chunk(M, p, s)\
- ((p)->head = (s|PINUSE_BIT|CINUSE_BIT))
-
-#else /* FOOTERS */
-
-/* Set foot of inuse chunk to be xor of mstate and seed */
-#define mark_inuse_foot(M,p,s)\
- (((mchunkptr)((char*)(p) + (s)))->prev_foot = ((size_t)(M) ^ mparams.magic))
-
-#define get_mstate_for(p)\
- ((mstate)(((mchunkptr)((char*)(p) +\
- (chunksize(p))))->prev_foot ^ mparams.magic))
-
-#define set_inuse(M,p,s)\
- ((p)->head = (((p)->head & PINUSE_BIT)|s|CINUSE_BIT),\
- (((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT), \
- mark_inuse_foot(M,p,s))
-
-#define set_inuse_and_pinuse(M,p,s)\
- ((p)->head = (s|PINUSE_BIT|CINUSE_BIT),\
- (((mchunkptr)(((char*)(p)) + (s)))->head |= PINUSE_BIT),\
- mark_inuse_foot(M,p,s))
-
-#define set_size_and_pinuse_of_inuse_chunk(M, p, s)\
- ((p)->head = (s|PINUSE_BIT|CINUSE_BIT),\
- mark_inuse_foot(M, p, s))
-
-#endif /* !FOOTERS */
-
-/* ---------------------------- setting mparams -------------------------- */
-
-/* Initialize mparams */
-static int init_mparams(void) {
-#ifdef NEED_GLOBAL_LOCK_INIT
- if (malloc_global_mutex_status <= 0)
- init_malloc_global_mutex();
-#endif
-
- ACQUIRE_MALLOC_GLOBAL_LOCK();
- if (mparams.magic == 0) {
- size_t magic;
- size_t psize;
- size_t gsize;
-
-#ifndef WIN32
- psize = malloc_getpagesize;
- gsize = ((DEFAULT_GRANULARITY != 0)? DEFAULT_GRANULARITY : psize);
-#else /* WIN32 */
- {
- SYSTEM_INFO system_info;
- GetSystemInfo(&system_info);
- psize = system_info.dwPageSize;
- gsize = ((DEFAULT_GRANULARITY != 0)?
- DEFAULT_GRANULARITY : system_info.dwAllocationGranularity);
- }
-#endif /* WIN32 */
-
- /* Sanity-check configuration:
- size_t must be unsigned and as wide as pointer type.
- ints must be at least 4 bytes.
- alignment must be at least 8.
- Alignment, min chunk size, and page size must all be powers of 2.
- */
- if ((sizeof(size_t) != sizeof(char*)) ||
- (MAX_SIZE_T < MIN_CHUNK_SIZE) ||
- (sizeof(int) < 4) ||
- (MALLOC_ALIGNMENT < (size_t)8U) ||
- ((MALLOC_ALIGNMENT & (MALLOC_ALIGNMENT-SIZE_T_ONE)) != 0) ||
- ((MCHUNK_SIZE & (MCHUNK_SIZE-SIZE_T_ONE)) != 0) ||
- ((gsize & (gsize-SIZE_T_ONE)) != 0) ||
- ((psize & (psize-SIZE_T_ONE)) != 0))
- ABORT;
-
- mparams.granularity = gsize;
- mparams.page_size = psize;
- mparams.mmap_threshold = DEFAULT_MMAP_THRESHOLD;
- mparams.trim_threshold = DEFAULT_TRIM_THRESHOLD;
-#if MORECORE_CONTIGUOUS
- mparams.default_mflags = USE_LOCK_BIT|USE_MMAP_BIT;
-#else /* MORECORE_CONTIGUOUS */
- mparams.default_mflags = USE_LOCK_BIT|USE_MMAP_BIT|USE_NONCONTIGUOUS_BIT;
-#endif /* MORECORE_CONTIGUOUS */
-
-#if !ONLY_MSPACES
- /* Set up lock for main malloc area */
- gm->mflags = mparams.default_mflags;
- (void)INITIAL_LOCK(&gm->mutex);
-#endif
-
- {
-#if USE_DEV_RANDOM
- int fd;
- unsigned char buf[sizeof(size_t)];
- /* Try to use /dev/urandom, else fall back on using time */
- if ((fd = open("/dev/urandom", O_RDONLY)) >= 0 &&
- read(fd, buf, sizeof(buf)) == sizeof(buf)) {
- magic = *((size_t *) buf);
- close(fd);
- }
- else
-#endif /* USE_DEV_RANDOM */
-#ifdef WIN32
- magic = (size_t)(GetTickCount() ^ (size_t)0x55555555U);
-#elif defined(LACKS_TIME_H)
- magic = (size_t)&magic ^ (size_t)0x55555555U;
-#else
- magic = (size_t)(time(0) ^ (size_t)0x55555555U);
-#endif
- magic |= (size_t)8U; /* ensure nonzero */
- magic &= ~(size_t)7U; /* improve chances of fault for bad values */
- /* Until memory modes commonly available, use volatile-write */
- (*(volatile size_t *)(&(mparams.magic))) = magic;
- }
- }
-
- RELEASE_MALLOC_GLOBAL_LOCK();
- return 1;
-}
-
-/* support for mallopt */
-static int change_mparam(int param_number, int value) {
- size_t val;
- ensure_initialization();
- val = (value == -1)? MAX_SIZE_T : (size_t)value;
- switch(param_number) {
- case M_TRIM_THRESHOLD:
- mparams.trim_threshold = val;
- return 1;
- case M_GRANULARITY:
- if (val >= mparams.page_size && ((val & (val-1)) == 0)) {
- mparams.granularity = val;
- return 1;
- }
- else
- return 0;
- case M_MMAP_THRESHOLD:
- mparams.mmap_threshold = val;
- return 1;
- default:
- return 0;
- }
-}
-
-#if DEBUG
-/* ------------------------- Debugging Support --------------------------- */
-
-/* Check properties of any chunk, whether free, inuse, mmapped etc */
-static void do_check_any_chunk(mstate m, mchunkptr p) {
- assert((is_aligned(chunk2mem(p))) || (p->head == FENCEPOST_HEAD));
- assert(ok_address(m, p));
-}
-
-/* Check properties of top chunk */
-static void do_check_top_chunk(mstate m, mchunkptr p) {
- msegmentptr sp = segment_holding(m, (char*)p);
- size_t sz = p->head & ~INUSE_BITS; /* third-lowest bit can be set! */
- assert(sp != 0);
- assert((is_aligned(chunk2mem(p))) || (p->head == FENCEPOST_HEAD));
- assert(ok_address(m, p));
- assert(sz == m->topsize);
- assert(sz > 0);
- assert(sz == ((sp->base + sp->size) - (char*)p) - TOP_FOOT_SIZE);
- assert(pinuse(p));
- assert(!pinuse(chunk_plus_offset(p, sz)));
-}
-
-/* Check properties of (inuse) mmapped chunks */
-static void do_check_mmapped_chunk(mstate m, mchunkptr p) {
- size_t sz = chunksize(p);
- size_t len = (sz + (p->prev_foot) + MMAP_FOOT_PAD);
- assert(is_mmapped(p));
- assert(use_mmap(m));
- assert((is_aligned(chunk2mem(p))) || (p->head == FENCEPOST_HEAD));
- assert(ok_address(m, p));
- assert(!is_small(sz));
- assert((len & (mparams.page_size-SIZE_T_ONE)) == 0);
- assert(chunk_plus_offset(p, sz)->head == FENCEPOST_HEAD);
- assert(chunk_plus_offset(p, sz+SIZE_T_SIZE)->head == 0);
-}
-
-/* Check properties of inuse chunks */
-static void do_check_inuse_chunk(mstate m, mchunkptr p) {
- do_check_any_chunk(m, p);
- assert(is_inuse(p));
- assert(next_pinuse(p));
- /* If not pinuse and not mmapped, previous chunk has OK offset */
- assert(is_mmapped(p) || pinuse(p) || next_chunk(prev_chunk(p)) == p);
- if (is_mmapped(p))
- do_check_mmapped_chunk(m, p);
-}
-
-/* Check properties of free chunks */
-static void do_check_free_chunk(mstate m, mchunkptr p) {
- size_t sz = chunksize(p);
- mchunkptr next = chunk_plus_offset(p, sz);
- do_check_any_chunk(m, p);
- assert(!is_inuse(p));
- assert(!next_pinuse(p));
- assert (!is_mmapped(p));
- if (p != m->dv && p != m->top) {
- if (sz >= MIN_CHUNK_SIZE) {
- assert((sz & CHUNK_ALIGN_MASK) == 0);
- assert(is_aligned(chunk2mem(p)));
- assert(next->prev_foot == sz);
- assert(pinuse(p));
- assert (next == m->top || is_inuse(next));
- assert(p->fd->bk == p);
- assert(p->bk->fd == p);
- }
- else /* markers are always of size SIZE_T_SIZE */
- assert(sz == SIZE_T_SIZE);
- }
-}
-
-/* Check properties of malloced chunks at the point they are malloced */
-static void do_check_malloced_chunk(mstate m, void* mem, size_t s) {
- if (mem != 0) {
- mchunkptr p = mem2chunk(mem);
- size_t sz = p->head & ~INUSE_BITS;
- do_check_inuse_chunk(m, p);
- assert((sz & CHUNK_ALIGN_MASK) == 0);
- assert(sz >= MIN_CHUNK_SIZE);
- assert(sz >= s);
- /* unless mmapped, size is less than MIN_CHUNK_SIZE more than request */
- assert(is_mmapped(p) || sz < (s + MIN_CHUNK_SIZE));
- }
-}
-
-/* Check a tree and its subtrees. */
-static void do_check_tree(mstate m, tchunkptr t) {
- tchunkptr head = 0;
- tchunkptr u = t;
- bindex_t tindex = t->index;
- size_t tsize = chunksize(t);
- bindex_t idx;
- compute_tree_index(tsize, idx);
- assert(tindex == idx);
- assert(tsize >= MIN_LARGE_SIZE);
- assert(tsize >= minsize_for_tree_index(idx));
- assert((idx == NTREEBINS-1) || (tsize < minsize_for_tree_index((idx+1))));
-
- do { /* traverse through chain of same-sized nodes */
- do_check_any_chunk(m, ((mchunkptr)u));
- assert(u->index == tindex);
- assert(chunksize(u) == tsize);
- assert(!is_inuse(u));
- assert(!next_pinuse(u));
- assert(u->fd->bk == u);
- assert(u->bk->fd == u);
- if (u->parent == 0) {
- assert(u->child[0] == 0);
- assert(u->child[1] == 0);
- }
- else {
- assert(head == 0); /* only one node on chain has parent */
- head = u;
- assert(u->parent != u);
- assert (u->parent->child[0] == u ||
- u->parent->child[1] == u ||
- *((tbinptr*)(u->parent)) == u);
- if (u->child[0] != 0) {
- assert(u->child[0]->parent == u);
- assert(u->child[0] != u);
- do_check_tree(m, u->child[0]);
- }
- if (u->child[1] != 0) {
- assert(u->child[1]->parent == u);
- assert(u->child[1] != u);
- do_check_tree(m, u->child[1]);
- }
- if (u->child[0] != 0 && u->child[1] != 0) {
- assert(chunksize(u->child[0]) < chunksize(u->child[1]));
- }
- }
- u = u->fd;
- } while (u != t);
- assert(head != 0);
-}
-
-/* Check all the chunks in a treebin. */
-static void do_check_treebin(mstate m, bindex_t i) {
- tbinptr* tb = treebin_at(m, i);
- tchunkptr t = *tb;
- int empty = (m->treemap & (1U << i)) == 0;
- if (t == 0)
- assert(empty);
- if (!empty)
- do_check_tree(m, t);
-}
-
-/* Check all the chunks in a smallbin. */
-static void do_check_smallbin(mstate m, bindex_t i) {
- sbinptr b = smallbin_at(m, i);
- mchunkptr p = b->bk;
- unsigned int empty = (m->smallmap & (1U << i)) == 0;
- if (p == b)
- assert(empty);
- if (!empty) {
- for (; p != b; p = p->bk) {
- size_t size = chunksize(p);
- mchunkptr q;
- /* each chunk claims to be free */
- do_check_free_chunk(m, p);
- /* chunk belongs in bin */
- assert(small_index(size) == i);
- assert(p->bk == b || chunksize(p->bk) == chunksize(p));
- /* chunk is followed by an inuse chunk */
- q = next_chunk(p);
- if (q->head != FENCEPOST_HEAD)
- do_check_inuse_chunk(m, q);
- }
- }
-}
-
-/* Find x in a bin. Used in other check functions. */
-static int bin_find(mstate m, mchunkptr x) {
- size_t size = chunksize(x);
- if (is_small(size)) {
- bindex_t sidx = small_index(size);
- sbinptr b = smallbin_at(m, sidx);
- if (smallmap_is_marked(m, sidx)) {
- mchunkptr p = b;
- do {
- if (p == x)
- return 1;
- } while ((p = p->fd) != b);
- }
- }
- else {
- bindex_t tidx;
- compute_tree_index(size, tidx);
- if (treemap_is_marked(m, tidx)) {
- tchunkptr t = *treebin_at(m, tidx);
- size_t sizebits = size << leftshift_for_tree_index(tidx);
- while (t != 0 && chunksize(t) != size) {
- t = t->child[(sizebits >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1];
- sizebits <<= 1;
- }
- if (t != 0) {
- tchunkptr u = t;
- do {
- if (u == (tchunkptr)x)
- return 1;
- } while ((u = u->fd) != t);
- }
- }
- }
- return 0;
-}
-
-/* Traverse each chunk and check it; return total */
-static size_t traverse_and_check(mstate m) {
- size_t sum = 0;
- if (is_initialized(m)) {
- msegmentptr s = &m->seg;
- sum += m->topsize + TOP_FOOT_SIZE;
- while (s != 0) {
- mchunkptr q = align_as_chunk(s->base);
- mchunkptr lastq = 0;
- assert(pinuse(q));
- while (segment_holds(s, q) &&
- q != m->top && q->head != FENCEPOST_HEAD) {
- sum += chunksize(q);
- if (is_inuse(q)) {
- assert(!bin_find(m, q));
- do_check_inuse_chunk(m, q);
- }
- else {
- assert(q == m->dv || bin_find(m, q));
- assert(lastq == 0 || is_inuse(lastq)); /* Not 2 consecutive free */
- do_check_free_chunk(m, q);
- }
- lastq = q;
- q = next_chunk(q);
- }
- s = s->next;
- }
- }
- return sum;
-}
-
-
-/* Check all properties of malloc_state. */
-static void do_check_malloc_state(mstate m) {
- bindex_t i;
- size_t total;
- /* check bins */
- for (i = 0; i < NSMALLBINS; ++i)
- do_check_smallbin(m, i);
- for (i = 0; i < NTREEBINS; ++i)
- do_check_treebin(m, i);
-
- if (m->dvsize != 0) { /* check dv chunk */
- do_check_any_chunk(m, m->dv);
- assert(m->dvsize == chunksize(m->dv));
- assert(m->dvsize >= MIN_CHUNK_SIZE);
- assert(bin_find(m, m->dv) == 0);
- }
-
- if (m->top != 0) { /* check top chunk */
- do_check_top_chunk(m, m->top);
- /*assert(m->topsize == chunksize(m->top)); redundant */
- assert(m->topsize > 0);
- assert(bin_find(m, m->top) == 0);
- }
-
- total = traverse_and_check(m);
- assert(total <= m->footprint);
- assert(m->footprint <= m->max_footprint);
-}
-#endif /* DEBUG */
-
-/* ----------------------------- statistics ------------------------------ */
-
-#if !NO_MALLINFO
-static struct mallinfo internal_mallinfo(mstate m) {
- struct mallinfo nm = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };
- ensure_initialization();
- if (!PREACTION(m)) {
- check_malloc_state(m);
- if (is_initialized(m)) {
- size_t nfree = SIZE_T_ONE; /* top always free */
- size_t mfree = m->topsize + TOP_FOOT_SIZE;
- size_t sum = mfree;
- msegmentptr s = &m->seg;
- while (s != 0) {
- mchunkptr q = align_as_chunk(s->base);
- while (segment_holds(s, q) &&
- q != m->top && q->head != FENCEPOST_HEAD) {
- size_t sz = chunksize(q);
- sum += sz;
- if (!is_inuse(q)) {
- mfree += sz;
- ++nfree;
- }
- q = next_chunk(q);
- }
- s = s->next;
- }
-
- nm.arena = sum;
- nm.ordblks = nfree;
- nm.hblkhd = m->footprint - sum;
- nm.usmblks = m->max_footprint;
- nm.uordblks = m->footprint - mfree;
- nm.fordblks = mfree;
- nm.keepcost = m->topsize;
- }
-
- POSTACTION(m);
- }
- return nm;
-}
-#endif /* !NO_MALLINFO */
-
-#if !NO_MALLOC_STATS
-static void internal_malloc_stats(mstate m) {
- ensure_initialization();
- if (!PREACTION(m)) {
- size_t maxfp = 0;
- size_t fp = 0;
- size_t used = 0;
- check_malloc_state(m);
- if (is_initialized(m)) {
- msegmentptr s = &m->seg;
- maxfp = m->max_footprint;
- fp = m->footprint;
- used = fp - (m->topsize + TOP_FOOT_SIZE);
-
- while (s != 0) {
- mchunkptr q = align_as_chunk(s->base);
- while (segment_holds(s, q) &&
- q != m->top && q->head != FENCEPOST_HEAD) {
- if (!is_inuse(q))
- used -= chunksize(q);
- q = next_chunk(q);
- }
- s = s->next;
- }
- }
- POSTACTION(m); /* drop lock */
- fprintf(stderr, "max system bytes = %10lu\n", (unsigned long)(maxfp));
- fprintf(stderr, "system bytes = %10lu\n", (unsigned long)(fp));
- fprintf(stderr, "in use bytes = %10lu\n", (unsigned long)(used));
- }
-}
-#endif /* NO_MALLOC_STATS */
-
-/* ----------------------- Operations on smallbins ----------------------- */
-
-/*
- Various forms of linking and unlinking are defined as macros. Even
- the ones for trees, which are very long but have very short typical
- paths. This is ugly but reduces reliance on inlining support of
- compilers.
-*/
-
-/* Link a free chunk into a smallbin */
-#define insert_small_chunk(M, P, S) {\
- bindex_t I = small_index(S);\
- mchunkptr B = smallbin_at(M, I);\
- mchunkptr F = B;\
- assert(S >= MIN_CHUNK_SIZE);\
- if (!smallmap_is_marked(M, I))\
- mark_smallmap(M, I);\
- else if (RTCHECK(ok_address(M, B->fd)))\
- F = B->fd;\
- else {\
- CORRUPTION_ERROR_ACTION(M);\
- }\
- B->fd = P;\
- F->bk = P;\
- P->fd = F;\
- P->bk = B;\
-}
-
-/* Unlink a chunk from a smallbin */
-#define unlink_small_chunk(M, P, S) {\
- mchunkptr F = P->fd;\
- mchunkptr B = P->bk;\
- bindex_t I = small_index(S);\
- assert(P != B);\
- assert(P != F);\
- assert(chunksize(P) == small_index2size(I));\
- if (RTCHECK(F == smallbin_at(M,I) || (ok_address(M, F) && F->bk == P))) { \
- if (B == F) {\
- clear_smallmap(M, I);\
- }\
- else if (RTCHECK(B == smallbin_at(M,I) ||\
- (ok_address(M, B) && B->fd == P))) {\
- F->bk = B;\
- B->fd = F;\
- }\
- else {\
- CORRUPTION_ERROR_ACTION(M);\
- }\
- }\
- else {\
- CORRUPTION_ERROR_ACTION(M);\
- }\
-}
-
-/* Unlink the first chunk from a smallbin */
-#define unlink_first_small_chunk(M, B, P, I) {\
- mchunkptr F = P->fd;\
- assert(P != B);\
- assert(P != F);\
- assert(chunksize(P) == small_index2size(I));\
- if (B == F) {\
- clear_smallmap(M, I);\
- }\
- else if (RTCHECK(ok_address(M, F) && F->bk == P)) {\
- F->bk = B;\
- B->fd = F;\
- }\
- else {\
- CORRUPTION_ERROR_ACTION(M);\
- }\
-}
-
-/* Replace dv node, binning the old one */
-/* Used only when dvsize known to be small */
-#define replace_dv(M, P, S) {\
- size_t DVS = M->dvsize;\
- assert(is_small(DVS));\
- if (DVS != 0) {\
- mchunkptr DV = M->dv;\
- insert_small_chunk(M, DV, DVS);\
- }\
- M->dvsize = S;\
- M->dv = P;\
-}
-
-/* ------------------------- Operations on trees ------------------------- */
-
-/* Insert chunk into tree */
-#define insert_large_chunk(M, X, S) {\
- tbinptr* H;\
- bindex_t I;\
- compute_tree_index(S, I);\
- H = treebin_at(M, I);\
- X->index = I;\
- X->child[0] = X->child[1] = 0;\
- if (!treemap_is_marked(M, I)) {\
- mark_treemap(M, I);\
- *H = X;\
- X->parent = (tchunkptr)H;\
- X->fd = X->bk = X;\
- }\
- else {\
- tchunkptr T = *H;\
- size_t K = S << leftshift_for_tree_index(I);\
- for (;;) {\
- if (chunksize(T) != S) {\
- tchunkptr* C = &(T->child[(K >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1]);\
- K <<= 1;\
- if (*C != 0)\
- T = *C;\
- else if (RTCHECK(ok_address(M, C))) {\
- *C = X;\
- X->parent = T;\
- X->fd = X->bk = X;\
- break;\
- }\
- else {\
- CORRUPTION_ERROR_ACTION(M);\
- break;\
- }\
- }\
- else {\
- tchunkptr F = T->fd;\
- if (RTCHECK(ok_address(M, T) && ok_address(M, F))) {\
- T->fd = F->bk = X;\
- X->fd = F;\
- X->bk = T;\
- X->parent = 0;\
- break;\
- }\
- else {\
- CORRUPTION_ERROR_ACTION(M);\
- break;\
- }\
- }\
- }\
- }\
-}
-
-/*
- Unlink steps:
-
- 1. If x is a chained node, unlink it from its same-sized fd/bk links
- and choose its bk node as its replacement.
- 2. If x was the last node of its size, but not a leaf node, it must
- be replaced with a leaf node (not merely one with an open left or
- right), to make sure that lefts and rights of descendents
- correspond properly to bit masks. We use the rightmost descendent
- of x. We could use any other leaf, but this is easy to locate and
- tends to counteract removal of leftmosts elsewhere, and so keeps
- paths shorter than minimally guaranteed. This doesn't loop much
- because on average a node in a tree is near the bottom.
- 3. If x is the base of a chain (i.e., has parent links) relink
- x's parent and children to x's replacement (or null if none).
-*/
-
-#define unlink_large_chunk(M, X) {\
- tchunkptr XP = X->parent;\
- tchunkptr R;\
- if (X->bk != X) {\
- tchunkptr F = X->fd;\
- R = X->bk;\
- if (RTCHECK(ok_address(M, F) && F->bk == X && R->fd == X)) {\
- F->bk = R;\
- R->fd = F;\
- }\
- else {\
- CORRUPTION_ERROR_ACTION(M);\
- }\
- }\
- else {\
- tchunkptr* RP;\
- if (((R = *(RP = &(X->child[1]))) != 0) ||\
- ((R = *(RP = &(X->child[0]))) != 0)) {\
- tchunkptr* CP;\
- while ((*(CP = &(R->child[1])) != 0) ||\
- (*(CP = &(R->child[0])) != 0)) {\
- R = *(RP = CP);\
- }\
- if (RTCHECK(ok_address(M, RP)))\
- *RP = 0;\
- else {\
- CORRUPTION_ERROR_ACTION(M);\
- }\
- }\
- }\
- if (XP != 0) {\
- tbinptr* H = treebin_at(M, X->index);\
- if (X == *H) {\
- if ((*H = R) == 0) \
- clear_treemap(M, X->index);\
- }\
- else if (RTCHECK(ok_address(M, XP))) {\
- if (XP->child[0] == X) \
- XP->child[0] = R;\
- else \
- XP->child[1] = R;\
- }\
- else\
- CORRUPTION_ERROR_ACTION(M);\
- if (R != 0) {\
- if (RTCHECK(ok_address(M, R))) {\
- tchunkptr C0, C1;\
- R->parent = XP;\
- if ((C0 = X->child[0]) != 0) {\
- if (RTCHECK(ok_address(M, C0))) {\
- R->child[0] = C0;\
- C0->parent = R;\
- }\
- else\
- CORRUPTION_ERROR_ACTION(M);\
- }\
- if ((C1 = X->child[1]) != 0) {\
- if (RTCHECK(ok_address(M, C1))) {\
- R->child[1] = C1;\
- C1->parent = R;\
- }\
- else\
- CORRUPTION_ERROR_ACTION(M);\
- }\
- }\
- else\
- CORRUPTION_ERROR_ACTION(M);\
- }\
- }\
-}
-
-/* Relays to large vs small bin operations */
-
-#define insert_chunk(M, P, S)\
- if (is_small(S)) insert_small_chunk(M, P, S)\
- else { tchunkptr TP = (tchunkptr)(P); insert_large_chunk(M, TP, S); }
-
-#define unlink_chunk(M, P, S)\
- if (is_small(S)) unlink_small_chunk(M, P, S)\
- else { tchunkptr TP = (tchunkptr)(P); unlink_large_chunk(M, TP); }
-
-
-/* Relays to internal calls to malloc/free from realloc, memalign etc */
-
-#if ONLY_MSPACES
-#define internal_malloc(m, b) mspace_malloc(m, b)
-#define internal_free(m, mem) mspace_free(m,mem);
-#else /* ONLY_MSPACES */
-#if MSPACES
-#define internal_malloc(m, b)\
- ((m == gm)? dlmalloc(b) : mspace_malloc(m, b))
-#define internal_free(m, mem)\
- if (m == gm) dlfree(mem); else mspace_free(m,mem);
-#else /* MSPACES */
-#define internal_malloc(m, b) dlmalloc(b)
-#define internal_free(m, mem) dlfree(mem)
-#endif /* MSPACES */
-#endif /* ONLY_MSPACES */
-
-/* ----------------------- Direct-mmapping chunks ----------------------- */
-
-/*
- Directly mmapped chunks are set up with an offset to the start of
- the mmapped region stored in the prev_foot field of the chunk. This
- allows reconstruction of the required argument to MUNMAP when freed,
- and also allows adjustment of the returned chunk to meet alignment
- requirements (especially in memalign).
-*/
-
-/* Malloc using mmap */
-static void* mmap_alloc(mstate m, size_t nb) {
- size_t mmsize = mmap_align(nb + SIX_SIZE_T_SIZES + CHUNK_ALIGN_MASK);
- if (m->footprint_limit != 0) {
- size_t fp = m->footprint + mmsize;
- if (fp <= m->footprint || fp > m->footprint_limit)
- return 0;
- }
- if (mmsize > nb) { /* Check for wrap around 0 */
- char* mm = (char*)(CALL_DIRECT_MMAP(mmsize));
- if (mm != CMFAIL) {
- size_t offset = align_offset(chunk2mem(mm));
- size_t psize = mmsize - offset - MMAP_FOOT_PAD;
- mchunkptr p = (mchunkptr)(mm + offset);
- p->prev_foot = offset;
- p->head = psize;
- mark_inuse_foot(m, p, psize);
- chunk_plus_offset(p, psize)->head = FENCEPOST_HEAD;
- chunk_plus_offset(p, psize+SIZE_T_SIZE)->head = 0;
-
- if (m->least_addr == 0 || mm < m->least_addr)
- m->least_addr = mm;
- if ((m->footprint += mmsize) > m->max_footprint)
- m->max_footprint = m->footprint;
- assert(is_aligned(chunk2mem(p)));
- check_mmapped_chunk(m, p);
- return chunk2mem(p);
- }
- }
- return 0;
-}
-
-/* Realloc using mmap */
-static mchunkptr mmap_resize(mstate m, mchunkptr oldp, size_t nb, int flags) {
- size_t oldsize = chunksize(oldp);
- flags = flags; /* placate people compiling -Wunused */
- if (is_small(nb)) /* Can't shrink mmap regions below small size */
- return 0;
- /* Keep old chunk if big enough but not too big */
- if (oldsize >= nb + SIZE_T_SIZE &&
- (oldsize - nb) <= (mparams.granularity << 1))
- return oldp;
- else {
- size_t offset = oldp->prev_foot;
- size_t oldmmsize = oldsize + offset + MMAP_FOOT_PAD;
- size_t newmmsize = mmap_align(nb + SIX_SIZE_T_SIZES + CHUNK_ALIGN_MASK);
- char* cp = (char*)CALL_MREMAP((char*)oldp - offset,
- oldmmsize, newmmsize, flags);
- if (cp != CMFAIL) {
- mchunkptr newp = (mchunkptr)(cp + offset);
- size_t psize = newmmsize - offset - MMAP_FOOT_PAD;
- newp->head = psize;
- mark_inuse_foot(m, newp, psize);
- chunk_plus_offset(newp, psize)->head = FENCEPOST_HEAD;
- chunk_plus_offset(newp, psize+SIZE_T_SIZE)->head = 0;
-
- if (cp < m->least_addr)
- m->least_addr = cp;
- if ((m->footprint += newmmsize - oldmmsize) > m->max_footprint)
- m->max_footprint = m->footprint;
- check_mmapped_chunk(m, newp);
- return newp;
- }
- }
- return 0;
-}
-
-
-/* -------------------------- mspace management -------------------------- */
-
-/* Initialize top chunk and its size */
-static void init_top(mstate m, mchunkptr p, size_t psize) {
- /* Ensure alignment */
- size_t offset = align_offset(chunk2mem(p));
- p = (mchunkptr)((char*)p + offset);
- psize -= offset;
-
- m->top = p;
- m->topsize = psize;
- p->head = psize | PINUSE_BIT;
- /* set size of fake trailing chunk holding overhead space only once */
- chunk_plus_offset(p, psize)->head = TOP_FOOT_SIZE;
- m->trim_check = mparams.trim_threshold; /* reset on each update */
-}
-
-/* Initialize bins for a new mstate that is otherwise zeroed out */
-static void init_bins(mstate m) {
- /* Establish circular links for smallbins */
- bindex_t i;
- for (i = 0; i < NSMALLBINS; ++i) {
- sbinptr bin = smallbin_at(m,i);
- bin->fd = bin->bk = bin;
- }
-}
-
-#if PROCEED_ON_ERROR
-
-/* default corruption action */
-static void reset_on_error(mstate m) {
- int i;
- ++malloc_corruption_error_count;
- /* Reinitialize fields to forget about all memory */
- m->smallmap = m->treemap = 0;
- m->dvsize = m->topsize = 0;
- m->seg.base = 0;
- m->seg.size = 0;
- m->seg.next = 0;
- m->top = m->dv = 0;
- for (i = 0; i < NTREEBINS; ++i)
- *treebin_at(m, i) = 0;
- init_bins(m);
-}
-#endif /* PROCEED_ON_ERROR */
-
-/* Allocate chunk and prepend remainder with chunk in successor base. */
-static void* prepend_alloc(mstate m, char* newbase, char* oldbase,
- size_t nb) {
- mchunkptr p = align_as_chunk(newbase);
- mchunkptr oldfirst = align_as_chunk(oldbase);
- size_t psize = (char*)oldfirst - (char*)p;
- mchunkptr q = chunk_plus_offset(p, nb);
- size_t qsize = psize - nb;
- set_size_and_pinuse_of_inuse_chunk(m, p, nb);
-
- assert((char*)oldfirst > (char*)q);
- assert(pinuse(oldfirst));
- assert(qsize >= MIN_CHUNK_SIZE);
-
- /* consolidate remainder with first chunk of old base */
- if (oldfirst == m->top) {
- size_t tsize = m->topsize += qsize;
- m->top = q;
- q->head = tsize | PINUSE_BIT;
- check_top_chunk(m, q);
- }
- else if (oldfirst == m->dv) {
- size_t dsize = m->dvsize += qsize;
- m->dv = q;
- set_size_and_pinuse_of_free_chunk(q, dsize);
- }
- else {
- if (!is_inuse(oldfirst)) {
- size_t nsize = chunksize(oldfirst);
- unlink_chunk(m, oldfirst, nsize);
- oldfirst = chunk_plus_offset(oldfirst, nsize);
- qsize += nsize;
- }
- set_free_with_pinuse(q, qsize, oldfirst);
- insert_chunk(m, q, qsize);
- check_free_chunk(m, q);
- }
-
- check_malloced_chunk(m, chunk2mem(p), nb);
- return chunk2mem(p);
-}
-
-/* Add a segment to hold a new noncontiguous region */
-static void add_segment(mstate m, char* tbase, size_t tsize, flag_t mmapped) {
- /* Determine locations and sizes of segment, fenceposts, old top */
- char* old_top = (char*)m->top;
- msegmentptr oldsp = segment_holding(m, old_top);
- char* old_end = oldsp->base + oldsp->size;
- size_t ssize = pad_request(sizeof(struct malloc_segment));
- char* rawsp = old_end - (ssize + FOUR_SIZE_T_SIZES + CHUNK_ALIGN_MASK);
- size_t offset = align_offset(chunk2mem(rawsp));
- char* asp = rawsp + offset;
- char* csp = (asp < (old_top + MIN_CHUNK_SIZE))? old_top : asp;
- mchunkptr sp = (mchunkptr)csp;
- msegmentptr ss = (msegmentptr)(chunk2mem(sp));
- mchunkptr tnext = chunk_plus_offset(sp, ssize);
- mchunkptr p = tnext;
- int nfences = 0;
-
- /* reset top to new space */
- init_top(m, (mchunkptr)tbase, tsize - TOP_FOOT_SIZE);
-
- /* Set up segment record */
- assert(is_aligned(ss));
- set_size_and_pinuse_of_inuse_chunk(m, sp, ssize);
- *ss = m->seg; /* Push current record */
- m->seg.base = tbase;
- m->seg.size = tsize;
- m->seg.sflags = mmapped;
- m->seg.next = ss;
-
- /* Insert trailing fenceposts */
- for (;;) {
- mchunkptr nextp = chunk_plus_offset(p, SIZE_T_SIZE);
- p->head = FENCEPOST_HEAD;
- ++nfences;
- if ((char*)(&(nextp->head)) < old_end)
- p = nextp;
- else
- break;
- }
- assert(nfences >= 2);
-
- /* Insert the rest of old top into a bin as an ordinary free chunk */
- if (csp != old_top) {
- mchunkptr q = (mchunkptr)old_top;
- size_t psize = csp - old_top;
- mchunkptr tn = chunk_plus_offset(q, psize);
- set_free_with_pinuse(q, psize, tn);
- insert_chunk(m, q, psize);
- }
-
- check_top_chunk(m, m->top);
-}
-
-/* -------------------------- System allocation -------------------------- */
-
-/* Get memory from system using MORECORE or MMAP */
-static void* sys_alloc(mstate m, size_t nb) {
- char* tbase = CMFAIL;
- size_t tsize = 0;
- flag_t mmap_flag = 0;
- size_t asize; /* allocation size */
-
- ensure_initialization();
-
- /* Directly map large chunks, but only if already initialized */
- if (use_mmap(m) && nb >= mparams.mmap_threshold && m->topsize != 0) {
- void* mem = mmap_alloc(m, nb);
- if (mem != 0)
- return mem;
- }
-
- asize = granularity_align(nb + SYS_ALLOC_PADDING);
- if (asize <= nb)
- return 0; /* wraparound */
- if (m->footprint_limit != 0) {
- size_t fp = m->footprint + asize;
- if (fp <= m->footprint || fp > m->footprint_limit)
- return 0;
- }
-
- /*
- Try getting memory in any of three ways (in most-preferred to
- least-preferred order):
- 1. A call to MORECORE that can normally contiguously extend memory.
- (disabled if not MORECORE_CONTIGUOUS or not HAVE_MORECORE or
- or main space is mmapped or a previous contiguous call failed)
- 2. A call to MMAP new space (disabled if not HAVE_MMAP).
- Note that under the default settings, if MORECORE is unable to
- fulfill a request, and HAVE_MMAP is true, then mmap is
- used as a noncontiguous system allocator. This is a useful backup
- strategy for systems with holes in address spaces -- in this case
- sbrk cannot contiguously expand the heap, but mmap may be able to
- find space.
- 3. A call to MORECORE that cannot usually contiguously extend memory.
- (disabled if not HAVE_MORECORE)
-
- In all cases, we need to request enough bytes from system to ensure
- we can malloc nb bytes upon success, so pad with enough space for
- top_foot, plus alignment-pad to make sure we don't lose bytes if
- not on boundary, and round this up to a granularity unit.
- */
-
- if (MORECORE_CONTIGUOUS && !use_noncontiguous(m)) {
- char* br = CMFAIL;
- msegmentptr ss = (m->top == 0)? 0 : segment_holding(m, (char*)m->top);
- ACQUIRE_MALLOC_GLOBAL_LOCK();
-
- if (ss == 0) { /* First time through or recovery */
- char* base = (char*)CALL_MORECORE(0);
- if (base != CMFAIL) {
- size_t fp;
- /* Adjust to end on a page boundary */
- if (!is_page_aligned(base))
- asize += (page_align((size_t)base) - (size_t)base);
- fp = m->footprint + asize; /* recheck limits */
- if (asize > nb && asize < HALF_MAX_SIZE_T &&
- (m->footprint_limit == 0 ||
- (fp > m->footprint && fp <= m->footprint_limit)) &&
- (br = (char*)(CALL_MORECORE(asize))) == base) {
- tbase = base;
- tsize = asize;
- }
- }
- }
- else {
- /* Subtract out existing available top space from MORECORE request. */
- asize = granularity_align(nb - m->topsize + SYS_ALLOC_PADDING);
- /* Use mem here only if it did continuously extend old space */
- if (asize < HALF_MAX_SIZE_T &&
- (br = (char*)(CALL_MORECORE(asize))) == ss->base+ss->size) {
- tbase = br;
- tsize = asize;
- }
- }
-
- if (tbase == CMFAIL) { /* Cope with partial failure */
- if (br != CMFAIL) { /* Try to use/extend the space we did get */
- if (asize < HALF_MAX_SIZE_T &&
- asize < nb + SYS_ALLOC_PADDING) {
- size_t esize = granularity_align(nb + SYS_ALLOC_PADDING - asize);
- if (esize < HALF_MAX_SIZE_T) {
- char* end = (char*)CALL_MORECORE(esize);
- if (end != CMFAIL)
- asize += esize;
- else { /* Can't use; try to release */
- (void) CALL_MORECORE(-asize);
- br = CMFAIL;
- }
- }
- }
- }
- if (br != CMFAIL) { /* Use the space we did get */
- tbase = br;
- tsize = asize;
- }
- else
- disable_contiguous(m); /* Don't try contiguous path in the future */
- }
-
- RELEASE_MALLOC_GLOBAL_LOCK();
- }
-
- if (HAVE_MMAP && tbase == CMFAIL) { /* Try MMAP */
- char* mp = (char*)(CALL_MMAP(asize));
- if (mp != CMFAIL) {
- tbase = mp;
- tsize = asize;
- mmap_flag = USE_MMAP_BIT;
- }
- }
-
- if (HAVE_MORECORE && tbase == CMFAIL) { /* Try noncontiguous MORECORE */
- if (asize < HALF_MAX_SIZE_T) {
- char* br = CMFAIL;
- char* end = CMFAIL;
- ACQUIRE_MALLOC_GLOBAL_LOCK();
- br = (char*)(CALL_MORECORE(asize));
- end = (char*)(CALL_MORECORE(0));
- RELEASE_MALLOC_GLOBAL_LOCK();
- if (br != CMFAIL && end != CMFAIL && br < end) {
- size_t ssize = end - br;
- if (ssize > nb + TOP_FOOT_SIZE) {
- tbase = br;
- tsize = ssize;
- }
- }
- }
- }
-
- if (tbase != CMFAIL) {
-
- if ((m->footprint += tsize) > m->max_footprint)
- m->max_footprint = m->footprint;
-
- if (!is_initialized(m)) { /* first-time initialization */
- if (m->least_addr == 0 || tbase < m->least_addr)
- m->least_addr = tbase;
- m->seg.base = tbase;
- m->seg.size = tsize;
- m->seg.sflags = mmap_flag;
- m->magic = mparams.magic;
- m->release_checks = MAX_RELEASE_CHECK_RATE;
- init_bins(m);
-#if !ONLY_MSPACES
- if (is_global(m))
- init_top(m, (mchunkptr)tbase, tsize - TOP_FOOT_SIZE);
- else
-#endif
- {
- /* Offset top by embedded malloc_state */
- mchunkptr mn = next_chunk(mem2chunk(m));
- init_top(m, mn, (size_t)((tbase + tsize) - (char*)mn) -TOP_FOOT_SIZE);
- }
- }
-
- else {
- /* Try to merge with an existing segment */
- msegmentptr sp = &m->seg;
- /* Only consider most recent segment if traversal suppressed */
- while (sp != 0 && tbase != sp->base + sp->size)
- sp = (NO_SEGMENT_TRAVERSAL) ? 0 : sp->next;
- if (sp != 0 &&
- !is_extern_segment(sp) &&
- (sp->sflags & USE_MMAP_BIT) == mmap_flag &&
- segment_holds(sp, m->top)) { /* append */
- sp->size += tsize;
- init_top(m, m->top, m->topsize + tsize);
- }
- else {
- if (tbase < m->least_addr)
- m->least_addr = tbase;
- sp = &m->seg;
- while (sp != 0 && sp->base != tbase + tsize)
- sp = (NO_SEGMENT_TRAVERSAL) ? 0 : sp->next;
- if (sp != 0 &&
- !is_extern_segment(sp) &&
- (sp->sflags & USE_MMAP_BIT) == mmap_flag) {
- char* oldbase = sp->base;
- sp->base = tbase;
- sp->size += tsize;
- return prepend_alloc(m, tbase, oldbase, nb);
- }
- else
- add_segment(m, tbase, tsize, mmap_flag);
- }
- }
-
- if (nb < m->topsize) { /* Allocate from new or extended top space */
- size_t rsize = m->topsize -= nb;
- mchunkptr p = m->top;
- mchunkptr r = m->top = chunk_plus_offset(p, nb);
- r->head = rsize | PINUSE_BIT;
- set_size_and_pinuse_of_inuse_chunk(m, p, nb);
- check_top_chunk(m, m->top);
- check_malloced_chunk(m, chunk2mem(p), nb);
- return chunk2mem(p);
- }
- }
-
- MALLOC_FAILURE_ACTION;
- return 0;
-}
-
-/* ----------------------- system deallocation -------------------------- */
-
-/* Unmap and unlink any mmapped segments that don't contain used chunks */
-static size_t release_unused_segments(mstate m) {
- size_t released = 0;
- int nsegs = 0;
- msegmentptr pred = &m->seg;
- msegmentptr sp = pred->next;
- while (sp != 0) {
- char* base = sp->base;
- size_t size = sp->size;
- msegmentptr next = sp->next;
- ++nsegs;
- if (is_mmapped_segment(sp) && !is_extern_segment(sp)) {
- mchunkptr p = align_as_chunk(base);
- size_t psize = chunksize(p);
- /* Can unmap if first chunk holds entire segment and not pinned */
- if (!is_inuse(p) && (char*)p + psize >= base + size - TOP_FOOT_SIZE) {
- tchunkptr tp = (tchunkptr)p;
- assert(segment_holds(sp, (char*)sp));
- if (p == m->dv) {
- m->dv = 0;
- m->dvsize = 0;
- }
- else {
- unlink_large_chunk(m, tp);
- }
- if (CALL_MUNMAP(base, size) == 0) {
- released += size;
- m->footprint -= size;
- /* unlink obsoleted record */
- sp = pred;
- sp->next = next;
- }
- else { /* back out if cannot unmap */
- insert_large_chunk(m, tp, psize);
- }
- }
- }
- if (NO_SEGMENT_TRAVERSAL) /* scan only first segment */
- break;
- pred = sp;
- sp = next;
- }
- /* Reset check counter */
- m->release_checks = ((nsegs > MAX_RELEASE_CHECK_RATE)?
- nsegs : MAX_RELEASE_CHECK_RATE);
- return released;
-}
-
-static int sys_trim(mstate m, size_t pad) {
- size_t released = 0;
- ensure_initialization();
- if (pad < MAX_REQUEST && is_initialized(m)) {
- pad += TOP_FOOT_SIZE; /* ensure enough room for segment overhead */
-
- if (m->topsize > pad) {
- /* Shrink top space in granularity-size units, keeping at least one */
- size_t unit = mparams.granularity;
- size_t extra = ((m->topsize - pad + (unit - SIZE_T_ONE)) / unit -
- SIZE_T_ONE) * unit;
- msegmentptr sp = segment_holding(m, (char*)m->top);
-
- if (!is_extern_segment(sp)) {
- if (is_mmapped_segment(sp)) {
- if (HAVE_MMAP &&
- sp->size >= extra &&
- !has_segment_link(m, sp)) { /* can't shrink if pinned */
- size_t newsize = sp->size - extra;
- /* Prefer mremap, fall back to munmap */
- if ((CALL_MREMAP(sp->base, sp->size, newsize, 0) != MFAIL) ||
- (CALL_MUNMAP(sp->base + newsize, extra) == 0)) {
- released = extra;
- }
- }
- }
- else if (HAVE_MORECORE) {
- if (extra >= HALF_MAX_SIZE_T) /* Avoid wrapping negative */
- extra = (HALF_MAX_SIZE_T) + SIZE_T_ONE - unit;
- ACQUIRE_MALLOC_GLOBAL_LOCK();
- {
- /* Make sure end of memory is where we last set it. */
- char* old_br = (char*)(CALL_MORECORE(0));
- if (old_br == sp->base + sp->size) {
- char* rel_br = (char*)(CALL_MORECORE(-extra));
- char* new_br = (char*)(CALL_MORECORE(0));
- if (rel_br != CMFAIL && new_br < old_br)
- released = old_br - new_br;
- }
- }
- RELEASE_MALLOC_GLOBAL_LOCK();
- }
- }
-
- if (released != 0) {
- sp->size -= released;
- m->footprint -= released;
- init_top(m, m->top, m->topsize - released);
- check_top_chunk(m, m->top);
- }
- }
-
- /* Unmap any unused mmapped segments */
- if (HAVE_MMAP)
- released += release_unused_segments(m);
-
- /* On failure, disable autotrim to avoid repeated failed future calls */
- if (released == 0 && m->topsize > m->trim_check)
- m->trim_check = MAX_SIZE_T;
- }
-
- return (released != 0)? 1 : 0;
-}
-
-/* Consolidate and bin a chunk. Differs from exported versions
- of free mainly in that the chunk need not be marked as inuse.
-*/
-static void dispose_chunk(mstate m, mchunkptr p, size_t psize) {
- mchunkptr next = chunk_plus_offset(p, psize);
- if (!pinuse(p)) {
- mchunkptr prev;
- size_t prevsize = p->prev_foot;
- if (is_mmapped(p)) {
- psize += prevsize + MMAP_FOOT_PAD;
- if (CALL_MUNMAP((char*)p - prevsize, psize) == 0)
- m->footprint -= psize;
- return;
- }
- prev = chunk_minus_offset(p, prevsize);
- psize += prevsize;
- p = prev;
- if (RTCHECK(ok_address(m, prev))) { /* consolidate backward */
- if (p != m->dv) {
- unlink_chunk(m, p, prevsize);
- }
- else if ((next->head & INUSE_BITS) == INUSE_BITS) {
- m->dvsize = psize;
- set_free_with_pinuse(p, psize, next);
- return;
- }
- }
- else {
- CORRUPTION_ERROR_ACTION(m);
- return;
- }
- }
- if (RTCHECK(ok_address(m, next))) {
- if (!cinuse(next)) { /* consolidate forward */
- if (next == m->top) {
- size_t tsize = m->topsize += psize;
- m->top = p;
- p->head = tsize | PINUSE_BIT;
- if (p == m->dv) {
- m->dv = 0;
- m->dvsize = 0;
- }
- return;
- }
- else if (next == m->dv) {
- size_t dsize = m->dvsize += psize;
- m->dv = p;
- set_size_and_pinuse_of_free_chunk(p, dsize);
- return;
- }
- else {
- size_t nsize = chunksize(next);
- psize += nsize;
- unlink_chunk(m, next, nsize);
- set_size_and_pinuse_of_free_chunk(p, psize);
- if (p == m->dv) {
- m->dvsize = psize;
- return;
- }
- }
- }
- else {
- set_free_with_pinuse(p, psize, next);
- }
- insert_chunk(m, p, psize);
- }
- else {
- CORRUPTION_ERROR_ACTION(m);
- }
-}
-
-/* ---------------------------- malloc --------------------------- */
-
-/* allocate a large request from the best fitting chunk in a treebin */
-static void* tmalloc_large(mstate m, size_t nb) {
- tchunkptr v = 0;
- size_t rsize = -nb; /* Unsigned negation */
- tchunkptr t;
- bindex_t idx;
- compute_tree_index(nb, idx);
- if ((t = *treebin_at(m, idx)) != 0) {
- /* Traverse tree for this bin looking for node with size == nb */
- size_t sizebits = nb << leftshift_for_tree_index(idx);
- tchunkptr rst = 0; /* The deepest untaken right subtree */
- for (;;) {
- tchunkptr rt;
- size_t trem = chunksize(t) - nb;
- if (trem < rsize) {
- v = t;
- if ((rsize = trem) == 0)
- break;
- }
- rt = t->child[1];
- t = t->child[(sizebits >> (SIZE_T_BITSIZE-SIZE_T_ONE)) & 1];
- if (rt != 0 && rt != t)
- rst = rt;
- if (t == 0) {
- t = rst; /* set t to least subtree holding sizes > nb */
- break;
- }
- sizebits <<= 1;
- }
- }
- if (t == 0 && v == 0) { /* set t to root of next non-empty treebin */
- binmap_t leftbits = left_bits(idx2bit(idx)) & m->treemap;
- if (leftbits != 0) {
- bindex_t i;
- binmap_t leastbit = least_bit(leftbits);
- compute_bit2idx(leastbit, i);
- t = *treebin_at(m, i);
- }
- }
-
- while (t != 0) { /* find smallest of tree or subtree */
- size_t trem = chunksize(t) - nb;
- if (trem < rsize) {
- rsize = trem;
- v = t;
- }
- t = leftmost_child(t);
- }
-
- /* If dv is a better fit, return 0 so malloc will use it */
- if (v != 0 && rsize < (size_t)(m->dvsize - nb)) {
- if (RTCHECK(ok_address(m, v))) { /* split */
- mchunkptr r = chunk_plus_offset(v, nb);
- assert(chunksize(v) == rsize + nb);
- if (RTCHECK(ok_next(v, r))) {
- unlink_large_chunk(m, v);
- if (rsize < MIN_CHUNK_SIZE)
- set_inuse_and_pinuse(m, v, (rsize + nb));
- else {
- set_size_and_pinuse_of_inuse_chunk(m, v, nb);
- set_size_and_pinuse_of_free_chunk(r, rsize);
- insert_chunk(m, r, rsize);
- }
- return chunk2mem(v);
- }
- }
- CORRUPTION_ERROR_ACTION(m);
- }
- return 0;
-}
-
-/* allocate a small request from the best fitting chunk in a treebin */
-static void* tmalloc_small(mstate m, size_t nb) {
- tchunkptr t, v;
- size_t rsize;
- bindex_t i;
- binmap_t leastbit = least_bit(m->treemap);
- compute_bit2idx(leastbit, i);
- v = t = *treebin_at(m, i);
- rsize = chunksize(t) - nb;
-
- while ((t = leftmost_child(t)) != 0) {
- size_t trem = chunksize(t) - nb;
- if (trem < rsize) {
- rsize = trem;
- v = t;
- }
- }
-
- if (RTCHECK(ok_address(m, v))) {
- mchunkptr r = chunk_plus_offset(v, nb);
- assert(chunksize(v) == rsize + nb);
- if (RTCHECK(ok_next(v, r))) {
- unlink_large_chunk(m, v);
- if (rsize < MIN_CHUNK_SIZE)
- set_inuse_and_pinuse(m, v, (rsize + nb));
- else {
- set_size_and_pinuse_of_inuse_chunk(m, v, nb);
- set_size_and_pinuse_of_free_chunk(r, rsize);
- replace_dv(m, r, rsize);
- }
- return chunk2mem(v);
- }
- }
-
- CORRUPTION_ERROR_ACTION(m);
- return 0;
-}
-
-#if !ONLY_MSPACES
-
-void* dlmalloc(size_t bytes) {
- /*
- Basic algorithm:
- If a small request (< 256 bytes minus per-chunk overhead):
- 1. If one exists, use a remainderless chunk in associated smallbin.
- (Remainderless means that there are too few excess bytes to
- represent as a chunk.)
- 2. If it is big enough, use the dv chunk, which is normally the
- chunk adjacent to the one used for the most recent small request.
- 3. If one exists, split the smallest available chunk in a bin,
- saving remainder in dv.
- 4. If it is big enough, use the top chunk.
- 5. If available, get memory from system and use it
- Otherwise, for a large request:
- 1. Find the smallest available binned chunk that fits, and use it
- if it is better fitting than dv chunk, splitting if necessary.
- 2. If better fitting than any binned chunk, use the dv chunk.
- 3. If it is big enough, use the top chunk.
- 4. If request size >= mmap threshold, try to directly mmap this chunk.
- 5. If available, get memory from system and use it
-
- The ugly goto's here ensure that postaction occurs along all paths.
- */
-
-#if USE_LOCKS
- ensure_initialization(); /* initialize in sys_alloc if not using locks */
-#endif
-
- if (!PREACTION(gm)) {
- void* mem;
- size_t nb;
- if (bytes <= MAX_SMALL_REQUEST) {
- bindex_t idx;
- binmap_t smallbits;
- nb = (bytes < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(bytes);
- idx = small_index(nb);
- smallbits = gm->smallmap >> idx;
-
- if ((smallbits & 0x3U) != 0) { /* Remainderless fit to a smallbin. */
- mchunkptr b, p;
- idx += ~smallbits & 1; /* Uses next bin if idx empty */
- b = smallbin_at(gm, idx);
- p = b->fd;
- assert(chunksize(p) == small_index2size(idx));
- unlink_first_small_chunk(gm, b, p, idx);
- set_inuse_and_pinuse(gm, p, small_index2size(idx));
- mem = chunk2mem(p);
- check_malloced_chunk(gm, mem, nb);
- goto postaction;
- }
-
- else if (nb > gm->dvsize) {
- if (smallbits != 0) { /* Use chunk in next nonempty smallbin */
- mchunkptr b, p, r;
- size_t rsize;
- bindex_t i;
- binmap_t leftbits = (smallbits << idx) & left_bits(idx2bit(idx));
- binmap_t leastbit = least_bit(leftbits);
- compute_bit2idx(leastbit, i);
- b = smallbin_at(gm, i);
- p = b->fd;
- assert(chunksize(p) == small_index2size(i));
- unlink_first_small_chunk(gm, b, p, i);
- rsize = small_index2size(i) - nb;
- /* Fit here cannot be remainderless if 4byte sizes */
- if (SIZE_T_SIZE != 4 && rsize < MIN_CHUNK_SIZE)
- set_inuse_and_pinuse(gm, p, small_index2size(i));
- else {
- set_size_and_pinuse_of_inuse_chunk(gm, p, nb);
- r = chunk_plus_offset(p, nb);
- set_size_and_pinuse_of_free_chunk(r, rsize);
- replace_dv(gm, r, rsize);
- }
- mem = chunk2mem(p);
- check_malloced_chunk(gm, mem, nb);
- goto postaction;
- }
-
- else if (gm->treemap != 0 && (mem = tmalloc_small(gm, nb)) != 0) {
- check_malloced_chunk(gm, mem, nb);
- goto postaction;
- }
- }
- }
- else if (bytes >= MAX_REQUEST)
- nb = MAX_SIZE_T; /* Too big to allocate. Force failure (in sys alloc) */
- else {
- nb = pad_request(bytes);
- if (gm->treemap != 0 && (mem = tmalloc_large(gm, nb)) != 0) {
- check_malloced_chunk(gm, mem, nb);
- goto postaction;
- }
- }
-
- if (nb <= gm->dvsize) {
- size_t rsize = gm->dvsize - nb;
- mchunkptr p = gm->dv;
- if (rsize >= MIN_CHUNK_SIZE) { /* split dv */
- mchunkptr r = gm->dv = chunk_plus_offset(p, nb);
- gm->dvsize = rsize;
- set_size_and_pinuse_of_free_chunk(r, rsize);
- set_size_and_pinuse_of_inuse_chunk(gm, p, nb);
- }
- else { /* exhaust dv */
- size_t dvs = gm->dvsize;
- gm->dvsize = 0;
- gm->dv = 0;
- set_inuse_and_pinuse(gm, p, dvs);
- }
- mem = chunk2mem(p);
- check_malloced_chunk(gm, mem, nb);
- goto postaction;
- }
-
- else if (nb < gm->topsize) { /* Split top */
- size_t rsize = gm->topsize -= nb;
- mchunkptr p = gm->top;
- mchunkptr r = gm->top = chunk_plus_offset(p, nb);
- r->head = rsize | PINUSE_BIT;
- set_size_and_pinuse_of_inuse_chunk(gm, p, nb);
- mem = chunk2mem(p);
- check_top_chunk(gm, gm->top);
- check_malloced_chunk(gm, mem, nb);
- goto postaction;
- }
-
- mem = sys_alloc(gm, nb);
-
- postaction:
- POSTACTION(gm);
- return mem;
- }
-
- return 0;
-}
-
-/* ---------------------------- free --------------------------- */
-
-void dlfree(void* mem) {
- /*
- Consolidate freed chunks with preceeding or succeeding bordering
- free chunks, if they exist, and then place in a bin. Intermixed
- with special cases for top, dv, mmapped chunks, and usage errors.
- */
-
- if (mem != 0) {
- mchunkptr p = mem2chunk(mem);
-#if FOOTERS
- mstate fm = get_mstate_for(p);
- if (!ok_magic(fm)) {
- USAGE_ERROR_ACTION(fm, p);
- return;
- }
-#else /* FOOTERS */
-#define fm gm
-#endif /* FOOTERS */
- if (!PREACTION(fm)) {
- check_inuse_chunk(fm, p);
- if (RTCHECK(ok_address(fm, p) && ok_inuse(p))) {
- size_t psize = chunksize(p);
- mchunkptr next = chunk_plus_offset(p, psize);
- if (!pinuse(p)) {
- size_t prevsize = p->prev_foot;
- if (is_mmapped(p)) {
- psize += prevsize + MMAP_FOOT_PAD;
- if (CALL_MUNMAP((char*)p - prevsize, psize) == 0)
- fm->footprint -= psize;
- goto postaction;
- }
- else {
- mchunkptr prev = chunk_minus_offset(p, prevsize);
- psize += prevsize;
- p = prev;
- if (RTCHECK(ok_address(fm, prev))) { /* consolidate backward */
- if (p != fm->dv) {
- unlink_chunk(fm, p, prevsize);
- }
- else if ((next->head & INUSE_BITS) == INUSE_BITS) {
- fm->dvsize = psize;
- set_free_with_pinuse(p, psize, next);
- goto postaction;
- }
- }
- else
- goto erroraction;
- }
- }
-
- if (RTCHECK(ok_next(p, next) && ok_pinuse(next))) {
- if (!cinuse(next)) { /* consolidate forward */
- if (next == fm->top) {
- size_t tsize = fm->topsize += psize;
- fm->top = p;
- p->head = tsize | PINUSE_BIT;
- if (p == fm->dv) {
- fm->dv = 0;
- fm->dvsize = 0;
- }
- if (should_trim(fm, tsize))
- sys_trim(fm, 0);
- goto postaction;
- }
- else if (next == fm->dv) {
- size_t dsize = fm->dvsize += psize;
- fm->dv = p;
- set_size_and_pinuse_of_free_chunk(p, dsize);
- goto postaction;
- }
- else {
- size_t nsize = chunksize(next);
- psize += nsize;
- unlink_chunk(fm, next, nsize);
- set_size_and_pinuse_of_free_chunk(p, psize);
- if (p == fm->dv) {
- fm->dvsize = psize;
- goto postaction;
- }
- }
- }
- else
- set_free_with_pinuse(p, psize, next);
-
- if (is_small(psize)) {
- insert_small_chunk(fm, p, psize);
- check_free_chunk(fm, p);
- }
- else {
- tchunkptr tp = (tchunkptr)p;
- insert_large_chunk(fm, tp, psize);
- check_free_chunk(fm, p);
- if (--fm->release_checks == 0)
- release_unused_segments(fm);
- }
- goto postaction;
- }
- }
- erroraction:
- USAGE_ERROR_ACTION(fm, p);
- postaction:
- POSTACTION(fm);
- }
- }
-#if !FOOTERS
-#undef fm
-#endif /* FOOTERS */
-}
-
-void* dlcalloc(size_t n_elements, size_t elem_size) {
- void* mem;
- size_t req = 0;
- if (n_elements != 0) {
- req = n_elements * elem_size;
- if (((n_elements | elem_size) & ~(size_t)0xffff) &&
- (req / n_elements != elem_size))
- req = MAX_SIZE_T; /* force downstream failure on overflow */
- }
- mem = dlmalloc(req);
- if (mem != 0 && calloc_must_clear(mem2chunk(mem)))
- memset(mem, 0, req);
- return mem;
-}
-
-#endif /* !ONLY_MSPACES */
-
-/* ------------ Internal support for realloc, memalign, etc -------------- */
-
-/* Try to realloc; only in-place unless can_move true */
-static mchunkptr try_realloc_chunk(mstate m, mchunkptr p, size_t nb,
- int can_move) {
- mchunkptr newp = 0;
- size_t oldsize = chunksize(p);
- mchunkptr next = chunk_plus_offset(p, oldsize);
- if (RTCHECK(ok_address(m, p) && ok_inuse(p) &&
- ok_next(p, next) && ok_pinuse(next))) {
- if (is_mmapped(p)) {
- newp = mmap_resize(m, p, nb, can_move);
- }
- else if (oldsize >= nb) { /* already big enough */
- size_t rsize = oldsize - nb;
- if (rsize >= MIN_CHUNK_SIZE) { /* split off remainder */
- mchunkptr r = chunk_plus_offset(p, nb);
- set_inuse(m, p, nb);
- set_inuse(m, r, rsize);
- dispose_chunk(m, r, rsize);
- }
- newp = p;
- }
- else if (next == m->top) { /* extend into top */
- if (oldsize + m->topsize > nb) {
- size_t newsize = oldsize + m->topsize;
- size_t newtopsize = newsize - nb;
- mchunkptr newtop = chunk_plus_offset(p, nb);
- set_inuse(m, p, nb);
- newtop->head = newtopsize |PINUSE_BIT;
- m->top = newtop;
- m->topsize = newtopsize;
- newp = p;
- }
- }
- else if (next == m->dv) { /* extend into dv */
- size_t dvs = m->dvsize;
- if (oldsize + dvs >= nb) {
- size_t dsize = oldsize + dvs - nb;
- if (dsize >= MIN_CHUNK_SIZE) {
- mchunkptr r = chunk_plus_offset(p, nb);
- mchunkptr n = chunk_plus_offset(r, dsize);
- set_inuse(m, p, nb);
- set_size_and_pinuse_of_free_chunk(r, dsize);
- clear_pinuse(n);
- m->dvsize = dsize;
- m->dv = r;
- }
- else { /* exhaust dv */
- size_t newsize = oldsize + dvs;
- set_inuse(m, p, newsize);
- m->dvsize = 0;
- m->dv = 0;
- }
- newp = p;
- }
- }
- else if (!cinuse(next)) { /* extend into next free chunk */
- size_t nextsize = chunksize(next);
- if (oldsize + nextsize >= nb) {
- size_t rsize = oldsize + nextsize - nb;
- unlink_chunk(m, next, nextsize);
- if (rsize < MIN_CHUNK_SIZE) {
- size_t newsize = oldsize + nextsize;
- set_inuse(m, p, newsize);
- }
- else {
- mchunkptr r = chunk_plus_offset(p, nb);
- set_inuse(m, p, nb);
- set_inuse(m, r, rsize);
- dispose_chunk(m, r, rsize);
- }
- newp = p;
- }
- }
- }
- else {
- USAGE_ERROR_ACTION(m, oldmem);
- }
- return newp;
-}
-
-static void* internal_memalign(mstate m, size_t alignment, size_t bytes) {
- void* mem = 0;
- if (alignment < MIN_CHUNK_SIZE) /* must be at least a minimum chunk size */
- alignment = MIN_CHUNK_SIZE;
- if ((alignment & (alignment-SIZE_T_ONE)) != 0) {/* Ensure a power of 2 */
- size_t a = MALLOC_ALIGNMENT << 1;
- while (a < alignment) a <<= 1;
- alignment = a;
- }
- if (bytes >= MAX_REQUEST - alignment) {
- if (m != 0) { /* Test isn't needed but avoids compiler warning */
- MALLOC_FAILURE_ACTION;
- }
- }
- else {
- size_t nb = request2size(bytes);
- size_t req = nb + alignment + MIN_CHUNK_SIZE - CHUNK_OVERHEAD;
- mem = internal_malloc(m, req);
- if (mem != 0) {
- mchunkptr p = mem2chunk(mem);
- if (PREACTION(m))
- return 0;
- if ((((size_t)(mem)) & (alignment - 1)) != 0) { /* misaligned */
- /*
- Find an aligned spot inside chunk. Since we need to give
- back leading space in a chunk of at least MIN_CHUNK_SIZE, if
- the first calculation places us at a spot with less than
- MIN_CHUNK_SIZE leader, we can move to the next aligned spot.
- We've allocated enough total room so that this is always
- possible.
- */
- char* br = (char*)mem2chunk((size_t)(((size_t)((char*)mem + alignment -
- SIZE_T_ONE)) &
- -alignment));
- char* pos = ((size_t)(br - (char*)(p)) >= MIN_CHUNK_SIZE)?
- br : br+alignment;
- mchunkptr newp = (mchunkptr)pos;
- size_t leadsize = pos - (char*)(p);
- size_t newsize = chunksize(p) - leadsize;
-
- if (is_mmapped(p)) { /* For mmapped chunks, just adjust offset */
- newp->prev_foot = p->prev_foot + leadsize;
- newp->head = newsize;
- }
- else { /* Otherwise, give back leader, use the rest */
- set_inuse(m, newp, newsize);
- set_inuse(m, p, leadsize);
- dispose_chunk(m, p, leadsize);
- }
- p = newp;
- }
-
- /* Give back spare room at the end */
- if (!is_mmapped(p)) {
- size_t size = chunksize(p);
- if (size > nb + MIN_CHUNK_SIZE) {
- size_t remainder_size = size - nb;
- mchunkptr remainder = chunk_plus_offset(p, nb);
- set_inuse(m, p, nb);
- set_inuse(m, remainder, remainder_size);
- dispose_chunk(m, remainder, remainder_size);
- }
- }
-
- mem = chunk2mem(p);
- assert (chunksize(p) >= nb);
- assert(((size_t)mem & (alignment - 1)) == 0);
- check_inuse_chunk(m, p);
- POSTACTION(m);
- }
- }
- return mem;
-}
-
-/*
- Common support for independent_X routines, handling
- all of the combinations that can result.
- The opts arg has:
- bit 0 set if all elements are same size (using sizes[0])
- bit 1 set if elements should be zeroed
-*/
-static void** ialloc(mstate m,
- size_t n_elements,
- size_t* sizes,
- int opts,
- void* chunks[]) {
-
- size_t element_size; /* chunksize of each element, if all same */
- size_t contents_size; /* total size of elements */
- size_t array_size; /* request size of pointer array */
- void* mem; /* malloced aggregate space */
- mchunkptr p; /* corresponding chunk */
- size_t remainder_size; /* remaining bytes while splitting */
- void** marray; /* either "chunks" or malloced ptr array */
- mchunkptr array_chunk; /* chunk for malloced ptr array */
- flag_t was_enabled; /* to disable mmap */
- size_t size;
- size_t i;
-
- ensure_initialization();
- /* compute array length, if needed */
- if (chunks != 0) {
- if (n_elements == 0)
- return chunks; /* nothing to do */
- marray = chunks;
- array_size = 0;
- }
- else {
- /* if empty req, must still return chunk representing empty array */
- if (n_elements == 0)
- return (void**)internal_malloc(m, 0);
- marray = 0;
- array_size = request2size(n_elements * (sizeof(void*)));
- }
-
- /* compute total element size */
- if (opts & 0x1) { /* all-same-size */
- element_size = request2size(*sizes);
- contents_size = n_elements * element_size;
- }
- else { /* add up all the sizes */
- element_size = 0;
- contents_size = 0;
- for (i = 0; i != n_elements; ++i)
- contents_size += request2size(sizes[i]);
- }
-
- size = contents_size + array_size;
-
- /*
- Allocate the aggregate chunk. First disable direct-mmapping so
- malloc won't use it, since we would not be able to later
- free/realloc space internal to a segregated mmap region.
- */
- was_enabled = use_mmap(m);
- disable_mmap(m);
- mem = internal_malloc(m, size - CHUNK_OVERHEAD);
- if (was_enabled)
- enable_mmap(m);
- if (mem == 0)
- return 0;
-
- if (PREACTION(m)) return 0;
- p = mem2chunk(mem);
- remainder_size = chunksize(p);
-
- assert(!is_mmapped(p));
-
- if (opts & 0x2) { /* optionally clear the elements */
- memset((size_t*)mem, 0, remainder_size - SIZE_T_SIZE - array_size);
- }
-
- /* If not provided, allocate the pointer array as final part of chunk */
- if (marray == 0) {
- size_t array_chunk_size;
- array_chunk = chunk_plus_offset(p, contents_size);
- array_chunk_size = remainder_size - contents_size;
- marray = (void**) (chunk2mem(array_chunk));
- set_size_and_pinuse_of_inuse_chunk(m, array_chunk, array_chunk_size);
- remainder_size = contents_size;
- }
-
- /* split out elements */
- for (i = 0; ; ++i) {
- marray[i] = chunk2mem(p);
- if (i != n_elements-1) {
- if (element_size != 0)
- size = element_size;
- else
- size = request2size(sizes[i]);
- remainder_size -= size;
- set_size_and_pinuse_of_inuse_chunk(m, p, size);
- p = chunk_plus_offset(p, size);
- }
- else { /* the final element absorbs any overallocation slop */
- set_size_and_pinuse_of_inuse_chunk(m, p, remainder_size);
- break;
- }
- }
-
-#if DEBUG
- if (marray != chunks) {
- /* final element must have exactly exhausted chunk */
- if (element_size != 0) {
- assert(remainder_size == element_size);
- }
- else {
- assert(remainder_size == request2size(sizes[i]));
- }
- check_inuse_chunk(m, mem2chunk(marray));
- }
- for (i = 0; i != n_elements; ++i)
- check_inuse_chunk(m, mem2chunk(marray[i]));
-
-#endif /* DEBUG */
-
- POSTACTION(m);
- return marray;
-}
-
-/* Try to free all pointers in the given array.
- Note: this could be made faster, by delaying consolidation,
- at the price of disabling some user integrity checks, We
- still optimize some consolidations by combining adjacent
- chunks before freeing, which will occur often if allocated
- with ialloc or the array is sorted.
-*/
-static size_t internal_bulk_free(mstate m, void* array[], size_t nelem) {
- size_t unfreed = 0;
- if (!PREACTION(m)) {
- void** a;
- void** fence = &(array[nelem]);
- for (a = array; a != fence; ++a) {
- void* mem = *a;
- if (mem != 0) {
- mchunkptr p = mem2chunk(mem);
- size_t psize = chunksize(p);
-#if FOOTERS
- if (get_mstate_for(p) != m) {
- ++unfreed;
- continue;
- }
-#endif
- check_inuse_chunk(m, p);
- *a = 0;
- if (RTCHECK(ok_address(m, p) && ok_inuse(p))) {
- void ** b = a + 1; /* try to merge with next chunk */
- mchunkptr next = next_chunk(p);
- if (b != fence && *b == chunk2mem(next)) {
- size_t newsize = chunksize(next) + psize;
- set_inuse(m, p, newsize);
- *b = chunk2mem(p);
- }
- else
- dispose_chunk(m, p, psize);
- }
- else {
- CORRUPTION_ERROR_ACTION(m);
- break;
- }
- }
- }
- if (should_trim(m, m->topsize))
- sys_trim(m, 0);
- POSTACTION(m);
- }
- return unfreed;
-}
-
-/* Traversal */
-#if MALLOC_INSPECT_ALL
-static void internal_inspect_all(mstate m,
- void(*handler)(void *start,
- void *end,
- size_t used_bytes,
- void* callback_arg),
- void* arg) {
- if (is_initialized(m)) {
- mchunkptr top = m->top;
- msegmentptr s;
- for (s = &m->seg; s != 0; s = s->next) {
- mchunkptr q = align_as_chunk(s->base);
- while (segment_holds(s, q) && q->head != FENCEPOST_HEAD) {
- mchunkptr next = next_chunk(q);
- size_t sz = chunksize(q);
- size_t used;
- void* start;
- if (is_inuse(q)) {
- used = sz - CHUNK_OVERHEAD; /* must not be mmapped */
- start = chunk2mem(q);
- }
- else {
- used = 0;
- if (is_small(sz)) { /* offset by possible bookkeeping */
- start = (void*)((char*)q + sizeof(malloc_chunk));
- }
- else {
- start = (void*)((char*)q + sizeof(malloc_tree_chunk));
- }
- }
- if (start < (void*)next) /* skip if all space is bookkeeping */
- handler(start, next, used, arg);
- if (q == top)
- break;
- q = next;
- }
- }
- }
-}
-#endif /* MALLOC_INSPECT_ALL */
-
-/* ------------------ Exported realloc, memalign, etc -------------------- */
-
-#if !ONLY_MSPACES
-
-void* dlrealloc(void* oldmem, size_t bytes) {
- void* mem = 0;
- if (oldmem == 0) {
- mem = dlmalloc(bytes);
- }
- else if (bytes >= MAX_REQUEST) {
- MALLOC_FAILURE_ACTION;
- }
-#ifdef REALLOC_ZERO_BYTES_FREES
- else if (bytes == 0) {
- dlfree(oldmem);
- }
-#endif /* REALLOC_ZERO_BYTES_FREES */
- else {
- size_t nb = request2size(bytes);
- mchunkptr oldp = mem2chunk(oldmem);
-#if ! FOOTERS
- mstate m = gm;
-#else /* FOOTERS */
- mstate m = get_mstate_for(oldp);
- if (!ok_magic(m)) {
- USAGE_ERROR_ACTION(m, oldmem);
- return 0;
- }
-#endif /* FOOTERS */
- if (!PREACTION(m)) {
- mchunkptr newp = try_realloc_chunk(m, oldp, nb, 1);
- POSTACTION(m);
- if (newp != 0) {
- check_inuse_chunk(m, newp);
- mem = chunk2mem(newp);
- }
- else {
- mem = internal_malloc(m, bytes);
- if (mem != 0) {
- size_t oc = chunksize(oldp) - overhead_for(oldp);
- memcpy(mem, oldmem, (oc < bytes)? oc : bytes);
- internal_free(m, oldmem);
- }
- }
- }
- }
- return mem;
-}
-
-void* dlrealloc_in_place(void* oldmem, size_t bytes) {
- void* mem = 0;
- if (oldmem != 0) {
- if (bytes >= MAX_REQUEST) {
- MALLOC_FAILURE_ACTION;
- }
- else {
- size_t nb = request2size(bytes);
- mchunkptr oldp = mem2chunk(oldmem);
-#if ! FOOTERS
- mstate m = gm;
-#else /* FOOTERS */
- mstate m = get_mstate_for(oldp);
- if (!ok_magic(m)) {
- USAGE_ERROR_ACTION(m, oldmem);
- return 0;
- }
-#endif /* FOOTERS */
- if (!PREACTION(m)) {
- mchunkptr newp = try_realloc_chunk(m, oldp, nb, 0);
- POSTACTION(m);
- if (newp == oldp) {
- check_inuse_chunk(m, newp);
- mem = oldmem;
- }
- }
- }
- }
- return mem;
-}
-
-void* dlmemalign(size_t alignment, size_t bytes) {
- if (alignment <= MALLOC_ALIGNMENT) {
- return dlmalloc(bytes);
- }
- return internal_memalign(gm, alignment, bytes);
-}
-
-int dlposix_memalign(void** pp, size_t alignment, size_t bytes) {
- void* mem = 0;
- if (alignment == MALLOC_ALIGNMENT)
- mem = dlmalloc(bytes);
- else {
- size_t d = alignment / sizeof(void*);
- size_t r = alignment % sizeof(void*);
- if (r != 0 || d == 0 || (d & (d-SIZE_T_ONE)) != 0)
- return EINVAL;
- else if (bytes >= MAX_REQUEST - alignment) {
- if (alignment < MIN_CHUNK_SIZE)
- alignment = MIN_CHUNK_SIZE;
- mem = internal_memalign(gm, alignment, bytes);
- }
- }
- if (mem == 0)
- return ENOMEM;
- else {
- *pp = mem;
- return 0;
- }
-}
-
-void* dlvalloc(size_t bytes) {
- size_t pagesz;
- ensure_initialization();
- pagesz = mparams.page_size;
- return dlmemalign(pagesz, bytes);
-}
-
-void* dlpvalloc(size_t bytes) {
- size_t pagesz;
- ensure_initialization();
- pagesz = mparams.page_size;
- return dlmemalign(pagesz, (bytes + pagesz - SIZE_T_ONE) & ~(pagesz - SIZE_T_ONE));
-}
-
-void** dlindependent_calloc(size_t n_elements, size_t elem_size,
- void* chunks[]) {
- size_t sz = elem_size; /* serves as 1-element array */
- return ialloc(gm, n_elements, &sz, 3, chunks);
-}
-
-void** dlindependent_comalloc(size_t n_elements, size_t sizes[],
- void* chunks[]) {
- return ialloc(gm, n_elements, sizes, 0, chunks);
-}
-
-size_t dlbulk_free(void* array[], size_t nelem) {
- return internal_bulk_free(gm, array, nelem);
-}
-
-#if MALLOC_INSPECT_ALL
-void dlmalloc_inspect_all(void(*handler)(void *start,
- void *end,
- size_t used_bytes,
- void* callback_arg),
- void* arg) {
- ensure_initialization();
- if (!PREACTION(gm)) {
- internal_inspect_all(gm, handler, arg);
- POSTACTION(gm);
- }
-}
-#endif /* MALLOC_INSPECT_ALL */
-
-int dlmalloc_trim(size_t pad) {
- int result = 0;
- ensure_initialization();
- if (!PREACTION(gm)) {
- result = sys_trim(gm, pad);
- POSTACTION(gm);
- }
- return result;
-}
-
-size_t dlmalloc_footprint(void) {
- return gm->footprint;
-}
-
-size_t dlmalloc_max_footprint(void) {
- return gm->max_footprint;
-}
-
-size_t dlmalloc_footprint_limit(void) {
- size_t maf = gm->footprint_limit;
- return maf == 0 ? MAX_SIZE_T : maf;
-}
-
-size_t dlmalloc_set_footprint_limit(size_t bytes) {
- size_t result; /* invert sense of 0 */
- if (bytes == 0)
- result = granularity_align(1); /* Use minimal size */
- if (bytes == MAX_SIZE_T)
- result = 0; /* disable */
- else
- result = granularity_align(bytes);
- return gm->footprint_limit = result;
-}
-
-#if !NO_MALLINFO
-struct mallinfo dlmallinfo(void) {
- return internal_mallinfo(gm);
-}
-#endif /* NO_MALLINFO */
-
-#if !NO_MALLOC_STATS
-void dlmalloc_stats() {
- internal_malloc_stats(gm);
-}
-#endif /* NO_MALLOC_STATS */
-
-int dlmallopt(int param_number, int value) {
- return change_mparam(param_number, value);
-}
-
-size_t dlmalloc_usable_size(void* mem) {
- if (mem != 0) {
- mchunkptr p = mem2chunk(mem);
- if (is_inuse(p))
- return chunksize(p) - overhead_for(p);
- }
- return 0;
-}
-
-#endif /* !ONLY_MSPACES */
-
-/* ----------------------------- user mspaces ---------------------------- */
-
-#if MSPACES
-
-static mstate init_user_mstate(char* tbase, size_t tsize) {
- size_t msize = pad_request(sizeof(struct malloc_state));
- mchunkptr mn;
- mchunkptr msp = align_as_chunk(tbase);
- mstate m = (mstate)(chunk2mem(msp));
- memset(m, 0, msize);
- (void)INITIAL_LOCK(&m->mutex);
- msp->head = (msize|INUSE_BITS);
- m->seg.base = m->least_addr = tbase;
- m->seg.size = m->footprint = m->max_footprint = tsize;
- m->magic = mparams.magic;
- m->release_checks = MAX_RELEASE_CHECK_RATE;
- m->mflags = mparams.default_mflags;
- m->extp = 0;
- m->exts = 0;
- disable_contiguous(m);
- init_bins(m);
- mn = next_chunk(mem2chunk(m));
- init_top(m, mn, (size_t)((tbase + tsize) - (char*)mn) - TOP_FOOT_SIZE);
- check_top_chunk(m, m->top);
- return m;
-}
-
-mspace create_mspace(size_t capacity, int locked) {
- mstate m = 0;
- size_t msize;
- ensure_initialization();
- msize = pad_request(sizeof(struct malloc_state));
- if (capacity < (size_t) -(msize + TOP_FOOT_SIZE + mparams.page_size)) {
- size_t rs = ((capacity == 0)? mparams.granularity :
- (capacity + TOP_FOOT_SIZE + msize));
- size_t tsize = granularity_align(rs);
- char* tbase = (char*)(CALL_MMAP(tsize));
- if (tbase != CMFAIL) {
- m = init_user_mstate(tbase, tsize);
- m->seg.sflags = USE_MMAP_BIT;
- set_lock(m, locked);
- }
- }
- return (mspace)m;
-}
-
-mspace create_mspace_with_base(void* base, size_t capacity, int locked) {
- mstate m = 0;
- size_t msize;
- ensure_initialization();
- msize = pad_request(sizeof(struct malloc_state));
- if (capacity > msize + TOP_FOOT_SIZE &&
- capacity < (size_t) -(msize + TOP_FOOT_SIZE + mparams.page_size)) {
- m = init_user_mstate((char*)base, capacity);
- m->seg.sflags = EXTERN_BIT;
- set_lock(m, locked);
- }
- return (mspace)m;
-}
-
-int mspace_track_large_chunks(mspace msp, int enable) {
- int ret = 0;
- mstate ms = (mstate)msp;
- if (!PREACTION(ms)) {
- if (!use_mmap(ms))
- ret = 1;
- if (!enable)
- enable_mmap(ms);
- else
- disable_mmap(ms);
- POSTACTION(ms);
- }
- return ret;
-}
-
-size_t destroy_mspace(mspace msp) {
- size_t freed = 0;
- mstate ms = (mstate)msp;
- if (ok_magic(ms)) {
- msegmentptr sp = &ms->seg;
- (void)DESTROY_LOCK(&ms->mutex); /* destroy before unmapped */
- while (sp != 0) {
- char* base = sp->base;
- size_t size = sp->size;
- flag_t flag = sp->sflags;
- sp = sp->next;
- if ((flag & USE_MMAP_BIT) && !(flag & EXTERN_BIT) &&
- CALL_MUNMAP(base, size) == 0)
- freed += size;
- }
- }
- else {
- USAGE_ERROR_ACTION(ms,ms);
- }
- return freed;
-}
-
-/*
- mspace versions of routines are near-clones of the global
- versions. This is not so nice but better than the alternatives.
-*/
-
-void* mspace_malloc(mspace msp, size_t bytes) {
- mstate ms = (mstate)msp;
- if (!ok_magic(ms)) {
- USAGE_ERROR_ACTION(ms,ms);
- return 0;
- }
- if (!PREACTION(ms)) {
- void* mem;
- size_t nb;
- if (bytes <= MAX_SMALL_REQUEST) {
- bindex_t idx;
- binmap_t smallbits;
- nb = (bytes < MIN_REQUEST)? MIN_CHUNK_SIZE : pad_request(bytes);
- idx = small_index(nb);
- smallbits = ms->smallmap >> idx;
-
- if ((smallbits & 0x3U) != 0) { /* Remainderless fit to a smallbin. */
- mchunkptr b, p;
- idx += ~smallbits & 1; /* Uses next bin if idx empty */
- b = smallbin_at(ms, idx);
- p = b->fd;
- assert(chunksize(p) == small_index2size(idx));
- unlink_first_small_chunk(ms, b, p, idx);
- set_inuse_and_pinuse(ms, p, small_index2size(idx));
- mem = chunk2mem(p);
- check_malloced_chunk(ms, mem, nb);
- goto postaction;
- }
-
- else if (nb > ms->dvsize) {
- if (smallbits != 0) { /* Use chunk in next nonempty smallbin */
- mchunkptr b, p, r;
- size_t rsize;
- bindex_t i;
- binmap_t leftbits = (smallbits << idx) & left_bits(idx2bit(idx));
- binmap_t leastbit = least_bit(leftbits);
- compute_bit2idx(leastbit, i);
- b = smallbin_at(ms, i);
- p = b->fd;
- assert(chunksize(p) == small_index2size(i));
- unlink_first_small_chunk(ms, b, p, i);
- rsize = small_index2size(i) - nb;
- /* Fit here cannot be remainderless if 4byte sizes */
- if (SIZE_T_SIZE != 4 && rsize < MIN_CHUNK_SIZE)
- set_inuse_and_pinuse(ms, p, small_index2size(i));
- else {
- set_size_and_pinuse_of_inuse_chunk(ms, p, nb);
- r = chunk_plus_offset(p, nb);
- set_size_and_pinuse_of_free_chunk(r, rsize);
- replace_dv(ms, r, rsize);
- }
- mem = chunk2mem(p);
- check_malloced_chunk(ms, mem, nb);
- goto postaction;
- }
-
- else if (ms->treemap != 0 && (mem = tmalloc_small(ms, nb)) != 0) {
- check_malloced_chunk(ms, mem, nb);
- goto postaction;
- }
- }
- }
- else if (bytes >= MAX_REQUEST)
- nb = MAX_SIZE_T; /* Too big to allocate. Force failure (in sys alloc) */
- else {
- nb = pad_request(bytes);
- if (ms->treemap != 0 && (mem = tmalloc_large(ms, nb)) != 0) {
- check_malloced_chunk(ms, mem, nb);
- goto postaction;
- }
- }
-
- if (nb <= ms->dvsize) {
- size_t rsize = ms->dvsize - nb;
- mchunkptr p = ms->dv;
- if (rsize >= MIN_CHUNK_SIZE) { /* split dv */
- mchunkptr r = ms->dv = chunk_plus_offset(p, nb);
- ms->dvsize = rsize;
- set_size_and_pinuse_of_free_chunk(r, rsize);
- set_size_and_pinuse_of_inuse_chunk(ms, p, nb);
- }
- else { /* exhaust dv */
- size_t dvs = ms->dvsize;
- ms->dvsize = 0;
- ms->dv = 0;
- set_inuse_and_pinuse(ms, p, dvs);
- }
- mem = chunk2mem(p);
- check_malloced_chunk(ms, mem, nb);
- goto postaction;
- }
-
- else if (nb < ms->topsize) { /* Split top */
- size_t rsize = ms->topsize -= nb;
- mchunkptr p = ms->top;
- mchunkptr r = ms->top = chunk_plus_offset(p, nb);
- r->head = rsize | PINUSE_BIT;
- set_size_and_pinuse_of_inuse_chunk(ms, p, nb);
- mem = chunk2mem(p);
- check_top_chunk(ms, ms->top);
- check_malloced_chunk(ms, mem, nb);
- goto postaction;
- }
-
- mem = sys_alloc(ms, nb);
-
- postaction:
- POSTACTION(ms);
- return mem;
- }
-
- return 0;
-}
-
-void mspace_free(mspace msp, void* mem) {
- if (mem != 0) {
- mchunkptr p = mem2chunk(mem);
-#if FOOTERS
- mstate fm = get_mstate_for(p);
- msp = msp; /* placate people compiling -Wunused */
-#else /* FOOTERS */
- mstate fm = (mstate)msp;
-#endif /* FOOTERS */
- if (!ok_magic(fm)) {
- USAGE_ERROR_ACTION(fm, p);
- return;
- }
- if (!PREACTION(fm)) {
- check_inuse_chunk(fm, p);
- if (RTCHECK(ok_address(fm, p) && ok_inuse(p))) {
- size_t psize = chunksize(p);
- mchunkptr next = chunk_plus_offset(p, psize);
- if (!pinuse(p)) {
- size_t prevsize = p->prev_foot;
- if (is_mmapped(p)) {
- psize += prevsize + MMAP_FOOT_PAD;
- if (CALL_MUNMAP((char*)p - prevsize, psize) == 0)
- fm->footprint -= psize;
- goto postaction;
- }
- else {
- mchunkptr prev = chunk_minus_offset(p, prevsize);
- psize += prevsize;
- p = prev;
- if (RTCHECK(ok_address(fm, prev))) { /* consolidate backward */
- if (p != fm->dv) {
- unlink_chunk(fm, p, prevsize);
- }
- else if ((next->head & INUSE_BITS) == INUSE_BITS) {
- fm->dvsize = psize;
- set_free_with_pinuse(p, psize, next);
- goto postaction;
- }
- }
- else
- goto erroraction;
- }
- }
-
- if (RTCHECK(ok_next(p, next) && ok_pinuse(next))) {
- if (!cinuse(next)) { /* consolidate forward */
- if (next == fm->top) {
- size_t tsize = fm->topsize += psize;
- fm->top = p;
- p->head = tsize | PINUSE_BIT;
- if (p == fm->dv) {
- fm->dv = 0;
- fm->dvsize = 0;
- }
- if (should_trim(fm, tsize))
- sys_trim(fm, 0);
- goto postaction;
- }
- else if (next == fm->dv) {
- size_t dsize = fm->dvsize += psize;
- fm->dv = p;
- set_size_and_pinuse_of_free_chunk(p, dsize);
- goto postaction;
- }
- else {
- size_t nsize = chunksize(next);
- psize += nsize;
- unlink_chunk(fm, next, nsize);
- set_size_and_pinuse_of_free_chunk(p, psize);
- if (p == fm->dv) {
- fm->dvsize = psize;
- goto postaction;
- }
- }
- }
- else
- set_free_with_pinuse(p, psize, next);
-
- if (is_small(psize)) {
- insert_small_chunk(fm, p, psize);
- check_free_chunk(fm, p);
- }
- else {
- tchunkptr tp = (tchunkptr)p;
- insert_large_chunk(fm, tp, psize);
- check_free_chunk(fm, p);
- if (--fm->release_checks == 0)
- release_unused_segments(fm);
- }
- goto postaction;
- }
- }
- erroraction:
- USAGE_ERROR_ACTION(fm, p);
- postaction:
- POSTACTION(fm);
- }
- }
-}
-
-void* mspace_calloc(mspace msp, size_t n_elements, size_t elem_size) {
- void* mem;
- size_t req = 0;
- mstate ms = (mstate)msp;
- if (!ok_magic(ms)) {
- USAGE_ERROR_ACTION(ms,ms);
- return 0;
- }
- if (n_elements != 0) {
- req = n_elements * elem_size;
- if (((n_elements | elem_size) & ~(size_t)0xffff) &&
- (req / n_elements != elem_size))
- req = MAX_SIZE_T; /* force downstream failure on overflow */
- }
- mem = internal_malloc(ms, req);
- if (mem != 0 && calloc_must_clear(mem2chunk(mem)))
- memset(mem, 0, req);
- return mem;
-}
-
-void* mspace_realloc(mspace msp, void* oldmem, size_t bytes) {
- void* mem = 0;
- if (oldmem == 0) {
- mem = mspace_malloc(msp, bytes);
- }
- else if (bytes >= MAX_REQUEST) {
- MALLOC_FAILURE_ACTION;
- }
-#ifdef REALLOC_ZERO_BYTES_FREES
- else if (bytes == 0) {
- mspace_free(msp, oldmem);
- }
-#endif /* REALLOC_ZERO_BYTES_FREES */
- else {
- size_t nb = request2size(bytes);
- mchunkptr oldp = mem2chunk(oldmem);
-#if ! FOOTERS
- mstate m = (mstate)msp;
-#else /* FOOTERS */
- mstate m = get_mstate_for(oldp);
- if (!ok_magic(m)) {
- USAGE_ERROR_ACTION(m, oldmem);
- return 0;
- }
-#endif /* FOOTERS */
- if (!PREACTION(m)) {
- mchunkptr newp = try_realloc_chunk(m, oldp, nb, 1);
- POSTACTION(m);
- if (newp != 0) {
- check_inuse_chunk(m, newp);
- mem = chunk2mem(newp);
- }
- else {
- mem = mspace_malloc(m, bytes);
- if (mem != 0) {
- size_t oc = chunksize(oldp) - overhead_for(oldp);
- memcpy(mem, oldmem, (oc < bytes)? oc : bytes);
- mspace_free(m, oldmem);
- }
- }
- }
- }
- return mem;
-}
-
-void* mspace_realloc_in_place(mspace msp, void* oldmem, size_t bytes) {
- void* mem = 0;
- if (oldmem != 0) {
- if (bytes >= MAX_REQUEST) {
- MALLOC_FAILURE_ACTION;
- }
- else {
- size_t nb = request2size(bytes);
- mchunkptr oldp = mem2chunk(oldmem);
-#if ! FOOTERS
- mstate m = (mstate)msp;
-#else /* FOOTERS */
- mstate m = get_mstate_for(oldp);
- msp = msp; /* placate people compiling -Wunused */
- if (!ok_magic(m)) {
- USAGE_ERROR_ACTION(m, oldmem);
- return 0;
- }
-#endif /* FOOTERS */
- if (!PREACTION(m)) {
- mchunkptr newp = try_realloc_chunk(m, oldp, nb, 0);
- POSTACTION(m);
- if (newp == oldp) {
- check_inuse_chunk(m, newp);
- mem = oldmem;
- }
- }
- }
- }
- return mem;
-}
-
-void* mspace_memalign(mspace msp, size_t alignment, size_t bytes) {
- mstate ms = (mstate)msp;
- if (!ok_magic(ms)) {
- USAGE_ERROR_ACTION(ms,ms);
- return 0;
- }
- if (alignment <= MALLOC_ALIGNMENT)
- return mspace_malloc(msp, bytes);
- return internal_memalign(ms, alignment, bytes);
-}
-
-void** mspace_independent_calloc(mspace msp, size_t n_elements,
- size_t elem_size, void* chunks[]) {
- size_t sz = elem_size; /* serves as 1-element array */
- mstate ms = (mstate)msp;
- if (!ok_magic(ms)) {
- USAGE_ERROR_ACTION(ms,ms);
- return 0;
- }
- return ialloc(ms, n_elements, &sz, 3, chunks);
-}
-
-void** mspace_independent_comalloc(mspace msp, size_t n_elements,
- size_t sizes[], void* chunks[]) {
- mstate ms = (mstate)msp;
- if (!ok_magic(ms)) {
- USAGE_ERROR_ACTION(ms,ms);
- return 0;
- }
- return ialloc(ms, n_elements, sizes, 0, chunks);
-}
-
-size_t mspace_bulk_free(mspace msp, void* array[], size_t nelem) {
- return internal_bulk_free((mstate)msp, array, nelem);
-}
-
-#if MALLOC_INSPECT_ALL
-void mspace_inspect_all(mspace msp,
- void(*handler)(void *start,
- void *end,
- size_t used_bytes,
- void* callback_arg),
- void* arg) {
- mstate ms = (mstate)msp;
- if (ok_magic(ms)) {
- if (!PREACTION(ms)) {
- internal_inspect_all(ms, handler, arg);
- POSTACTION(ms);
- }
- }
- else {
- USAGE_ERROR_ACTION(ms,ms);
- }
-}
-#endif /* MALLOC_INSPECT_ALL */
-
-int mspace_trim(mspace msp, size_t pad) {
- int result = 0;
- mstate ms = (mstate)msp;
- if (ok_magic(ms)) {
- if (!PREACTION(ms)) {
- result = sys_trim(ms, pad);
- POSTACTION(ms);
- }
- }
- else {
- USAGE_ERROR_ACTION(ms,ms);
- }
- return result;
-}
-
-#if !NO_MALLOC_STATS
-void mspace_malloc_stats(mspace msp) {
- mstate ms = (mstate)msp;
- if (ok_magic(ms)) {
- internal_malloc_stats(ms);
- }
- else {
- USAGE_ERROR_ACTION(ms,ms);
- }
-}
-#endif /* NO_MALLOC_STATS */
-
-size_t mspace_footprint(mspace msp) {
- size_t result = 0;
- mstate ms = (mstate)msp;
- if (ok_magic(ms)) {
- result = ms->footprint;
- }
- else {
- USAGE_ERROR_ACTION(ms,ms);
- }
- return result;
-}
-
-size_t mspace_max_footprint(mspace msp) {
- size_t result = 0;
- mstate ms = (mstate)msp;
- if (ok_magic(ms)) {
- result = ms->max_footprint;
- }
- else {
- USAGE_ERROR_ACTION(ms,ms);
- }
- return result;
-}
-
-size_t mspace_footprint_limit(mspace msp) {
- size_t result = 0;
- mstate ms = (mstate)msp;
- if (ok_magic(ms)) {
- size_t maf = ms->footprint_limit;
- result = (maf == 0) ? MAX_SIZE_T : maf;
- }
- else {
- USAGE_ERROR_ACTION(ms,ms);
- }
- return result;
-}
-
-size_t mspace_set_footprint_limit(mspace msp, size_t bytes) {
- size_t result = 0;
- mstate ms = (mstate)msp;
- if (ok_magic(ms)) {
- if (bytes == 0)
- result = granularity_align(1); /* Use minimal size */
- if (bytes == MAX_SIZE_T)
- result = 0; /* disable */
- else
- result = granularity_align(bytes);
- ms->footprint_limit = result;
- }
- else {
- USAGE_ERROR_ACTION(ms,ms);
- }
- return result;
-}
-
-#if !NO_MALLINFO
-struct mallinfo mspace_mallinfo(mspace msp) {
- mstate ms = (mstate)msp;
- if (!ok_magic(ms)) {
- USAGE_ERROR_ACTION(ms,ms);
- }
- return internal_mallinfo(ms);
-}
-#endif /* NO_MALLINFO */
-
-size_t mspace_usable_size(void* mem) {
- if (mem != 0) {
- mchunkptr p = mem2chunk(mem);
- if (is_inuse(p))
- return chunksize(p) - overhead_for(p);
- }
- return 0;
-}
-
-int mspace_mallopt(int param_number, int value) {
- return change_mparam(param_number, value);
-}
-
-#endif /* MSPACES */
-
-
-/* -------------------- Alternative MORECORE functions ------------------- */
-
-/*
- Guidelines for creating a custom version of MORECORE:
-
- * For best performance, MORECORE should allocate in multiples of pagesize.
- * MORECORE may allocate more memory than requested. (Or even less,
- but this will usually result in a malloc failure.)
- * MORECORE must not allocate memory when given argument zero, but
- instead return one past the end address of memory from previous
- nonzero call.
- * For best performance, consecutive calls to MORECORE with positive
- arguments should return increasing addresses, indicating that
- space has been contiguously extended.
- * Even though consecutive calls to MORECORE need not return contiguous
- addresses, it must be OK for malloc'ed chunks to span multiple
- regions in those cases where they do happen to be contiguous.
- * MORECORE need not handle negative arguments -- it may instead
- just return MFAIL when given negative arguments.
- Negative arguments are always multiples of pagesize. MORECORE
- must not misinterpret negative args as large positive unsigned
- args. You can suppress all such calls from even occurring by defining
- MORECORE_CANNOT_TRIM,
-
- As an example alternative MORECORE, here is a custom allocator
- kindly contributed for pre-OSX macOS. It uses virtually but not
- necessarily physically contiguous non-paged memory (locked in,
- present and won't get swapped out). You can use it by uncommenting
- this section, adding some #includes, and setting up the appropriate
- defines above:
-
- #define MORECORE osMoreCore
-
- There is also a shutdown routine that should somehow be called for
- cleanup upon program exit.
-
- #define MAX_POOL_ENTRIES 100
- #define MINIMUM_MORECORE_SIZE (64 * 1024U)
- static int next_os_pool;
- void *our_os_pools[MAX_POOL_ENTRIES];
-
- void *osMoreCore(int size)
- {
- void *ptr = 0;
- static void *sbrk_top = 0;
-
- if (size > 0)
- {
- if (size < MINIMUM_MORECORE_SIZE)
- size = MINIMUM_MORECORE_SIZE;
- if (CurrentExecutionLevel() == kTaskLevel)
- ptr = PoolAllocateResident(size + RM_PAGE_SIZE, 0);
- if (ptr == 0)
- {
- return (void *) MFAIL;
- }
- // save ptrs so they can be freed during cleanup
- our_os_pools[next_os_pool] = ptr;
- next_os_pool++;
- ptr = (void *) ((((size_t) ptr) + RM_PAGE_MASK) & ~RM_PAGE_MASK);
- sbrk_top = (char *) ptr + size;
- return ptr;
- }
- else if (size < 0)
- {
- // we don't currently support shrink behavior
- return (void *) MFAIL;
- }
- else
- {
- return sbrk_top;
- }
- }
-
- // cleanup any allocated memory pools
- // called as last thing before shutting down driver
-
- void osCleanupMem(void)
- {
- void **ptr;
-
- for (ptr = our_os_pools; ptr < &our_os_pools[MAX_POOL_ENTRIES]; ptr++)
- if (*ptr)
- {
- PoolDeallocate(*ptr);
- *ptr = 0;
- }
- }
-
-*/
-
-
-/* -----------------------------------------------------------------------
-History:
- v2.8.5 Sun May 22 10:26:02 2011 Doug Lea (dl at gee)
- * Always perform unlink checks unless INSECURE
- * Add posix_memalign.
- * Improve realloc to expand in more cases; expose realloc_in_place.
- Thanks to Peter Buhr for the suggestion.
- * Add footprint_limit, inspect_all, bulk_free. Thanks
- to Barry Hayes and others for the suggestions.
- * Internal refactorings to avoid calls while holding locks
- * Use non-reentrant locks by default. Thanks to Roland McGrath
- for the suggestion.
- * Small fixes to mspace_destroy, reset_on_error.
- * Various configuration extensions/changes. Thanks
- to all who contributed these.
-
- V2.8.4a Thu Apr 28 14:39:43 2011 (dl at gee.cs.oswego.edu)
- * Update Creative Commons URL
-
- V2.8.4 Wed May 27 09:56:23 2009 Doug Lea (dl at gee)
- * Use zeros instead of prev foot for is_mmapped
- * Add mspace_track_large_chunks; thanks to Jean Brouwers
- * Fix set_inuse in internal_realloc; thanks to Jean Brouwers
- * Fix insufficient sys_alloc padding when using 16byte alignment
- * Fix bad error check in mspace_footprint
- * Adaptations for ptmalloc; thanks to Wolfram Gloger.
- * Reentrant spin locks; thanks to Earl Chew and others
- * Win32 improvements; thanks to Niall Douglas and Earl Chew
- * Add NO_SEGMENT_TRAVERSAL and MAX_RELEASE_CHECK_RATE options
- * Extension hook in malloc_state
- * Various small adjustments to reduce warnings on some compilers
- * Various configuration extensions/changes for more platforms. Thanks
- to all who contributed these.
-
- V2.8.3 Thu Sep 22 11:16:32 2005 Doug Lea (dl at gee)
- * Add max_footprint functions
- * Ensure all appropriate literals are size_t
- * Fix conditional compilation problem for some #define settings
- * Avoid concatenating segments with the one provided
- in create_mspace_with_base
- * Rename some variables to avoid compiler shadowing warnings
- * Use explicit lock initialization.
- * Better handling of sbrk interference.
- * Simplify and fix segment insertion, trimming and mspace_destroy
- * Reinstate REALLOC_ZERO_BYTES_FREES option from 2.7.x
- * Thanks especially to Dennis Flanagan for help on these.
-
- V2.8.2 Sun Jun 12 16:01:10 2005 Doug Lea (dl at gee)
- * Fix memalign brace error.
-
- V2.8.1 Wed Jun 8 16:11:46 2005 Doug Lea (dl at gee)
- * Fix improper #endif nesting in C++
- * Add explicit casts needed for C++
-
- V2.8.0 Mon May 30 14:09:02 2005 Doug Lea (dl at gee)
- * Use trees for large bins
- * Support mspaces
- * Use segments to unify sbrk-based and mmap-based system allocation,
- removing need for emulation on most platforms without sbrk.
- * Default safety checks
- * Optional footer checks. Thanks to William Robertson for the idea.
- * Internal code refactoring
- * Incorporate suggestions and platform-specific changes.
- Thanks to Dennis Flanagan, Colin Plumb, Niall Douglas,
- Aaron Bachmann, Emery Berger, and others.
- * Speed up non-fastbin processing enough to remove fastbins.
- * Remove useless cfree() to avoid conflicts with other apps.
- * Remove internal memcpy, memset. Compilers handle builtins better.
- * Remove some options that no one ever used and rename others.
-
- V2.7.2 Sat Aug 17 09:07:30 2002 Doug Lea (dl at gee)
- * Fix malloc_state bitmap array misdeclaration
-
- V2.7.1 Thu Jul 25 10:58:03 2002 Doug Lea (dl at gee)
- * Allow tuning of FIRST_SORTED_BIN_SIZE
- * Use PTR_UINT as type for all ptr->int casts. Thanks to John Belmonte.
- * Better detection and support for non-contiguousness of MORECORE.
- Thanks to Andreas Mueller, Conal Walsh, and Wolfram Gloger
- * Bypass most of malloc if no frees. Thanks To Emery Berger.
- * Fix freeing of old top non-contiguous chunk im sysmalloc.
- * Raised default trim and map thresholds to 256K.
- * Fix mmap-related #defines. Thanks to Lubos Lunak.
- * Fix copy macros; added LACKS_FCNTL_H. Thanks to Neal Walfield.
- * Branch-free bin calculation
- * Default trim and mmap thresholds now 256K.
-
- V2.7.0 Sun Mar 11 14:14:06 2001 Doug Lea (dl at gee)
- * Introduce independent_comalloc and independent_calloc.
- Thanks to Michael Pachos for motivation and help.
- * Make optional .h file available
- * Allow > 2GB requests on 32bit systems.
- * new WIN32 sbrk, mmap, munmap, lock code from <Walter@GeNeSys-e.de>.
- Thanks also to Andreas Mueller <a.mueller at paradatec.de>,
- and Anonymous.
- * Allow override of MALLOC_ALIGNMENT (Thanks to Ruud Waij for
- helping test this.)
- * memalign: check alignment arg
- * realloc: don't try to shift chunks backwards, since this
- leads to more fragmentation in some programs and doesn't
- seem to help in any others.
- * Collect all cases in malloc requiring system memory into sysmalloc
- * Use mmap as backup to sbrk
- * Place all internal state in malloc_state
- * Introduce fastbins (although similar to 2.5.1)
- * Many minor tunings and cosmetic improvements
- * Introduce USE_PUBLIC_MALLOC_WRAPPERS, USE_MALLOC_LOCK
- * Introduce MALLOC_FAILURE_ACTION, MORECORE_CONTIGUOUS
- Thanks to Tony E. Bennett <tbennett@nvidia.com> and others.
- * Include errno.h to support default failure action.
-
- V2.6.6 Sun Dec 5 07:42:19 1999 Doug Lea (dl at gee)
- * return null for negative arguments
- * Added Several WIN32 cleanups from Martin C. Fong <mcfong at yahoo.com>
- * Add 'LACKS_SYS_PARAM_H' for those systems without 'sys/param.h'
- (e.g. WIN32 platforms)
- * Cleanup header file inclusion for WIN32 platforms
- * Cleanup code to avoid Microsoft Visual C++ compiler complaints
- * Add 'USE_DL_PREFIX' to quickly allow co-existence with existing
- memory allocation routines
- * Set 'malloc_getpagesize' for WIN32 platforms (needs more work)
- * Use 'assert' rather than 'ASSERT' in WIN32 code to conform to
- usage of 'assert' in non-WIN32 code
- * Improve WIN32 'sbrk()' emulation's 'findRegion()' routine to
- avoid infinite loop
- * Always call 'fREe()' rather than 'free()'
-
- V2.6.5 Wed Jun 17 15:57:31 1998 Doug Lea (dl at gee)
- * Fixed ordering problem with boundary-stamping
-
- V2.6.3 Sun May 19 08:17:58 1996 Doug Lea (dl at gee)
- * Added pvalloc, as recommended by H.J. Liu
- * Added 64bit pointer support mainly from Wolfram Gloger
- * Added anonymously donated WIN32 sbrk emulation
- * Malloc, calloc, getpagesize: add optimizations from Raymond Nijssen
- * malloc_extend_top: fix mask error that caused wastage after
- foreign sbrks
- * Add linux mremap support code from HJ Liu
-
- V2.6.2 Tue Dec 5 06:52:55 1995 Doug Lea (dl at gee)
- * Integrated most documentation with the code.
- * Add support for mmap, with help from
- Wolfram Gloger (Gloger@lrz.uni-muenchen.de).
- * Use last_remainder in more cases.
- * Pack bins using idea from colin@nyx10.cs.du.edu
- * Use ordered bins instead of best-fit threshhold
- * Eliminate block-local decls to simplify tracing and debugging.
- * Support another case of realloc via move into top
- * Fix error occuring when initial sbrk_base not word-aligned.
- * Rely on page size for units instead of SBRK_UNIT to
- avoid surprises about sbrk alignment conventions.
- * Add mallinfo, mallopt. Thanks to Raymond Nijssen
- (raymond@es.ele.tue.nl) for the suggestion.
- * Add `pad' argument to malloc_trim and top_pad mallopt parameter.
- * More precautions for cases where other routines call sbrk,
- courtesy of Wolfram Gloger (Gloger@lrz.uni-muenchen.de).
- * Added macros etc., allowing use in linux libc from
- H.J. Lu (hjl@gnu.ai.mit.edu)
- * Inverted this history list
-
- V2.6.1 Sat Dec 2 14:10:57 1995 Doug Lea (dl at gee)
- * Re-tuned and fixed to behave more nicely with V2.6.0 changes.
- * Removed all preallocation code since under current scheme
- the work required to undo bad preallocations exceeds
- the work saved in good cases for most test programs.
- * No longer use return list or unconsolidated bins since
- no scheme using them consistently outperforms those that don't
- given above changes.
- * Use best fit for very large chunks to prevent some worst-cases.
- * Added some support for debugging
-
- V2.6.0 Sat Nov 4 07:05:23 1995 Doug Lea (dl at gee)
- * Removed footers when chunks are in use. Thanks to
- Paul Wilson (wilson@cs.texas.edu) for the suggestion.
-
- V2.5.4 Wed Nov 1 07:54:51 1995 Doug Lea (dl at gee)
- * Added malloc_trim, with help from Wolfram Gloger
- (wmglo@Dent.MED.Uni-Muenchen.DE).
-
- V2.5.3 Tue Apr 26 10:16:01 1994 Doug Lea (dl at g)
-
- V2.5.2 Tue Apr 5 16:20:40 1994 Doug Lea (dl at g)
- * realloc: try to expand in both directions
- * malloc: swap order of clean-bin strategy;
- * realloc: only conditionally expand backwards
- * Try not to scavenge used bins
- * Use bin counts as a guide to preallocation
- * Occasionally bin return list chunks in first scan
- * Add a few optimizations from colin@nyx10.cs.du.edu
-
- V2.5.1 Sat Aug 14 15:40:43 1993 Doug Lea (dl at g)
- * faster bin computation & slightly different binning
- * merged all consolidations to one part of malloc proper
- (eliminating old malloc_find_space & malloc_clean_bin)
- * Scan 2 returns chunks (not just 1)
- * Propagate failure in realloc if malloc returns 0
- * Add stuff to allow compilation on non-ANSI compilers
- from kpv@research.att.com
-
- V2.5 Sat Aug 7 07:41:59 1993 Doug Lea (dl at g.oswego.edu)
- * removed potential for odd address access in prev_chunk
- * removed dependency on getpagesize.h
- * misc cosmetics and a bit more internal documentation
- * anticosmetics: mangled names in macros to evade debugger strangeness
- * tested on sparc, hp-700, dec-mips, rs6000
- with gcc & native cc (hp, dec only) allowing
- Detlefs & Zorn comparison study (in SIGPLAN Notices.)
-
- Trial version Fri Aug 28 13:14:29 1992 Doug Lea (dl at g.oswego.edu)
- * Based loosely on libg++-1.2X malloc. (It retains some of the overall
- structure of old version, but most details differ.)
-
-*/
-