Move stuff around

1 files changed, 787 insertions, 0 deletions

diff --git a/src/lib/lua/loadlib.c b/src/lib/lua/loadlib.c
new file mode 100644
index 0000000..7911928
--- /dev/null
+++ b/src/lib/lua/loadlib.c
@@ -0,0 +1,787 @@
+/*
+** $Id: loadlib.c,v 1.127 2015/11/23 11:30:45 roberto Exp $
+** Dynamic library loader for Lua
+** See Copyright Notice in lua.h
+**
+** This module contains an implementation of loadlib for Unix systems
+** that have dlfcn, an implementation for Windows, and a stub for other
+** systems.
+*/
+
+#define loadlib_c
+#define LUA_LIB
+
+#include "lprefix.h"
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "lua.h"
+
+#include "lauxlib.h"
+#include "lualib.h"
+
+
+/*
+** LUA_PATH_VAR and LUA_CPATH_VAR are the names of the environment
+** variables that Lua check to set its paths.
+*/
+#if !defined(LUA_PATH_VAR)
+#define LUA_PATH_VAR	"LUA_PATH"
+#endif
+
+#if !defined(LUA_CPATH_VAR)
+#define LUA_CPATH_VAR	"LUA_CPATH"
+#endif
+
+#define LUA_PATHSUFFIX		"_" LUA_VERSION_MAJOR "_" LUA_VERSION_MINOR
+
+#define LUA_PATHVARVERSION		LUA_PATH_VAR LUA_PATHSUFFIX
+#define LUA_CPATHVARVERSION		LUA_CPATH_VAR LUA_PATHSUFFIX
+
+/*
+** LUA_PATH_SEP is the character that separates templates in a path.
+** LUA_PATH_MARK is the string that marks the substitution points in a
+** template.
+** LUA_EXEC_DIR in a Windows path is replaced by the executable's
+** directory.
+** LUA_IGMARK is a mark to ignore all before it when building the
+** luaopen_ function name.
+*/
+#if !defined (LUA_PATH_SEP)
+#define LUA_PATH_SEP		";"
+#endif
+#if !defined (LUA_PATH_MARK)
+#define LUA_PATH_MARK		"?"
+#endif
+#if !defined (LUA_EXEC_DIR)
+#define LUA_EXEC_DIR		"!"
+#endif
+#if !defined (LUA_IGMARK)
+#define LUA_IGMARK		"-"
+#endif
+
+
+/*
+** LUA_CSUBSEP is the character that replaces dots in submodule names
+** when searching for a C loader.
+** LUA_LSUBSEP is the character that replaces dots in submodule names
+** when searching for a Lua loader.
+*/
+#if !defined(LUA_CSUBSEP)
+#define LUA_CSUBSEP		LUA_DIRSEP
+#endif
+
+#if !defined(LUA_LSUBSEP)
+#define LUA_LSUBSEP		LUA_DIRSEP
+#endif
+
+
+/* prefix for open functions in C libraries */
+#define LUA_POF		"luaopen_"
+
+/* separator for open functions in C libraries */
+#define LUA_OFSEP	"_"
+
+
+/*
+** unique key for table in the registry that keeps handles
+** for all loaded C libraries
+*/
+static const int CLIBS = 0;
+
+#define LIB_FAIL	"open"
+
+#define setprogdir(L)		((void)0)
+
+
+/*
+** system-dependent functions
+*/
+
+/*
+** unload library 'lib'
+*/
+static void lsys_unloadlib (void *lib);
+
+/*
+** load C library in file 'path'. If 'seeglb', load with all names in
+** the library global.
+** Returns the library; in case of error, returns NULL plus an
+** error string in the stack.
+*/
+static void *lsys_load (lua_State *L, const char *path, int seeglb);
+
+/*
+** Try to find a function named 'sym' in library 'lib'.
+** Returns the function; in case of error, returns NULL plus an
+** error string in the stack.
+*/
+static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym);
+
+
+
+
+#if defined(LUA_USE_DLOPEN)	/* { */
+/*
+** {========================================================================
+** This is an implementation of loadlib based on the dlfcn interface.
+** The dlfcn interface is available in Linux, SunOS, Solaris, IRIX, FreeBSD,
+** NetBSD, AIX 4.2, HPUX 11, and  probably most other Unix flavors, at least
+** as an emulation layer on top of native functions.
+** =========================================================================
+*/
+
+#include <dlfcn.h>
+
+/*
+** Macro to convert pointer-to-void* to pointer-to-function. This cast
+** is undefined according to ISO C, but POSIX assumes that it works.
+** (The '__extension__' in gnu compilers is only to avoid warnings.)
+*/
+#if defined(__GNUC__)
+#define cast_func(p) (__extension__ (lua_CFunction)(p))
+#else
+#define cast_func(p) ((lua_CFunction)(p))
+#endif
+
+
+static void lsys_unloadlib (void *lib) {
+  dlclose(lib);
+}
+
+
+static void *lsys_load (lua_State *L, const char *path, int seeglb) {
+  void *lib = dlopen(path, RTLD_NOW | (seeglb ? RTLD_GLOBAL : RTLD_LOCAL));
+  if (lib == NULL) lua_pushstring(L, dlerror());
+  return lib;
+}
+
+
+static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym) {
+  lua_CFunction f = cast_func(dlsym(lib, sym));
+  if (f == NULL) lua_pushstring(L, dlerror());
+  return f;
+}
+
+/* }====================================================== */
+
+
+
+#elif defined(LUA_DL_DLL)	/* }{ */
+/*
+** {======================================================================
+** This is an implementation of loadlib for Windows using native functions.
+** =======================================================================
+*/
+
+#include <windows.h>
+
+#undef setprogdir
+
+/*
+** optional flags for LoadLibraryEx
+*/
+#if !defined(LUA_LLE_FLAGS)
+#define LUA_LLE_FLAGS	0
+#endif
+
+
+static void setprogdir (lua_State *L) {
+  char buff[MAX_PATH + 1];
+  char *lb;
+  DWORD nsize = sizeof(buff)/sizeof(char);
+  DWORD n = GetModuleFileNameA(NULL, buff, nsize);
+  if (n == 0 || n == nsize || (lb = strrchr(buff, '\\')) == NULL)
+    luaL_error(L, "unable to get ModuleFileName");
+  else {
+    *lb = '\0';
+    luaL_gsub(L, lua_tostring(L, -1), LUA_EXEC_DIR, buff);
+    lua_remove(L, -2);  /* remove original string */
+  }
+}
+
+
+static void pusherror (lua_State *L) {
+  int error = GetLastError();
+  char buffer[128];
+  if (FormatMessageA(FORMAT_MESSAGE_IGNORE_INSERTS | FORMAT_MESSAGE_FROM_SYSTEM,
+      NULL, error, 0, buffer, sizeof(buffer)/sizeof(char), NULL))
+    lua_pushstring(L, buffer);
+  else
+    lua_pushfstring(L, "system error %d\n", error);
+}
+
+static void lsys_unloadlib (void *lib) {
+  FreeLibrary((HMODULE)lib);
+}
+
+
+static void *lsys_load (lua_State *L, const char *path, int seeglb) {
+  HMODULE lib = LoadLibraryExA(path, NULL, LUA_LLE_FLAGS);
+  (void)(seeglb);  /* not used: symbols are 'global' by default */
+  if (lib == NULL) pusherror(L);
+  return lib;
+}
+
+
+static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym) {
+  lua_CFunction f = (lua_CFunction)GetProcAddress((HMODULE)lib, sym);
+  if (f == NULL) pusherror(L);
+  return f;
+}
+
+/* }====================================================== */
+
+
+#else				/* }{ */
+/*
+** {======================================================
+** Fallback for other systems
+** =======================================================
+*/
+
+#undef LIB_FAIL
+#define LIB_FAIL	"absent"
+
+
+#define DLMSG	"dynamic libraries not enabled; check your Lua installation"
+
+
+static void lsys_unloadlib (void *lib) {
+  (void)(lib);  /* not used */
+}
+
+
+static void *lsys_load (lua_State *L, const char *path, int seeglb) {
+  (void)(path); (void)(seeglb);  /* not used */
+  lua_pushliteral(L, DLMSG);
+  return NULL;
+}
+
+
+static lua_CFunction lsys_sym (lua_State *L, void *lib, const char *sym) {
+  (void)(lib); (void)(sym);  /* not used */
+  lua_pushliteral(L, DLMSG);
+  return NULL;
+}
+
+/* }====================================================== */
+#endif				/* } */
+
+
+/*
+** return registry.CLIBS[path]
+*/
+static void *checkclib (lua_State *L, const char *path) {
+  void *plib;
+  lua_rawgetp(L, LUA_REGISTRYINDEX, &CLIBS);
+  lua_getfield(L, -1, path);
+  plib = lua_touserdata(L, -1);  /* plib = CLIBS[path] */
+  lua_pop(L, 2);  /* pop CLIBS table and 'plib' */
+  return plib;
+}
+
+
+/*
+** registry.CLIBS[path] = plib        -- for queries
+** registry.CLIBS[#CLIBS + 1] = plib  -- also keep a list of all libraries
+*/
+static void addtoclib (lua_State *L, const char *path, void *plib) {
+  lua_rawgetp(L, LUA_REGISTRYINDEX, &CLIBS);
+  lua_pushlightuserdata(L, plib);
+  lua_pushvalue(L, -1);
+  lua_setfield(L, -3, path);  /* CLIBS[path] = plib */
+  lua_rawseti(L, -2, luaL_len(L, -2) + 1);  /* CLIBS[#CLIBS + 1] = plib */
+  lua_pop(L, 1);  /* pop CLIBS table */
+}
+
+
+/*
+** __gc tag method for CLIBS table: calls 'lsys_unloadlib' for all lib
+** handles in list CLIBS
+*/
+static int gctm (lua_State *L) {
+  lua_Integer n = luaL_len(L, 1);
+  for (; n >= 1; n--) {  /* for each handle, in reverse order */
+    lua_rawgeti(L, 1, n);  /* get handle CLIBS[n] */
+    lsys_unloadlib(lua_touserdata(L, -1));
+    lua_pop(L, 1);  /* pop handle */
+  }
+  return 0;
+}
+
+
+
+/* error codes for 'lookforfunc' */
+#define ERRLIB		1
+#define ERRFUNC		2
+
+/*
+** Look for a C function named 'sym' in a dynamically loaded library
+** 'path'.
+** First, check whether the library is already loaded; if not, try
+** to load it.
+** Then, if 'sym' is '*', return true (as library has been loaded).
+** Otherwise, look for symbol 'sym' in the library and push a
+** C function with that symbol.
+** Return 0 and 'true' or a function in the stack; in case of
+** errors, return an error code and an error message in the stack.
+*/
+static int lookforfunc (lua_State *L, const char *path, const char *sym) {
+  void *reg = checkclib(L, path);  /* check loaded C libraries */
+  if (reg == NULL) {  /* must load library? */
+    reg = lsys_load(L, path, *sym == '*');  /* global symbols if 'sym'=='*' */
+    if (reg == NULL) return ERRLIB;  /* unable to load library */
+    addtoclib(L, path, reg);
+  }
+  if (*sym == '*') {  /* loading only library (no function)? */
+    lua_pushboolean(L, 1);  /* return 'true' */
+    return 0;  /* no errors */
+  }
+  else {
+    lua_CFunction f = lsys_sym(L, reg, sym);
+    if (f == NULL)
+      return ERRFUNC;  /* unable to find function */
+    lua_pushcfunction(L, f);  /* else create new function */
+    return 0;  /* no errors */
+  }
+}
+
+
+static int ll_loadlib (lua_State *L) {
+  const char *path = luaL_checkstring(L, 1);
+  const char *init = luaL_checkstring(L, 2);
+  int stat = lookforfunc(L, path, init);
+  if (stat == 0)  /* no errors? */
+    return 1;  /* return the loaded function */
+  else {  /* error; error message is on stack top */
+    lua_pushnil(L);
+    lua_insert(L, -2);
+    lua_pushstring(L, (stat == ERRLIB) ?  LIB_FAIL : "init");
+    return 3;  /* return nil, error message, and where */
+  }
+}
+
+
+
+/*
+** {======================================================
+** 'require' function
+** =======================================================
+*/
+
+
+static int readable (const char *filename) {
+  FILE *f = fopen(filename, "r");  /* try to open file */
+  if (f == NULL) return 0;  /* open failed */
+  fclose(f);
+  return 1;
+}
+
+
+static const char *pushnexttemplate (lua_State *L, const char *path) {
+  const char *l;
+  while (*path == *LUA_PATH_SEP) path++;  /* skip separators */
+  if (*path == '\0') return NULL;  /* no more templates */
+  l = strchr(path, *LUA_PATH_SEP);  /* find next separator */
+  if (l == NULL) l = path + strlen(path);
+  lua_pushlstring(L, path, l - path);  /* template */
+  return l;
+}
+
+
+static const char *searchpath (lua_State *L, const char *name,
+                                             const char *path,
+                                             const char *sep,
+                                             const char *dirsep) {
+  luaL_Buffer msg;  /* to build error message */
+  luaL_buffinit(L, &msg);
+  if (*sep != '\0')  /* non-empty separator? */
+    name = luaL_gsub(L, name, sep, dirsep);  /* replace it by 'dirsep' */
+  while ((path = pushnexttemplate(L, path)) != NULL) {
+    const char *filename = luaL_gsub(L, lua_tostring(L, -1),
+                                     LUA_PATH_MARK, name);
+    lua_remove(L, -2);  /* remove path template */
+    if (readable(filename))  /* does file exist and is readable? */
+      return filename;  /* return that file name */
+    lua_pushfstring(L, "\n\tno file '%s'", filename);
+    lua_remove(L, -2);  /* remove file name */
+    luaL_addvalue(&msg);  /* concatenate error msg. entry */
+  }
+  luaL_pushresult(&msg);  /* create error message */
+  return NULL;  /* not found */
+}
+
+
+static int ll_searchpath (lua_State *L) {
+  const char *f = searchpath(L, luaL_checkstring(L, 1),
+                                luaL_checkstring(L, 2),
+                                luaL_optstring(L, 3, "."),
+                                luaL_optstring(L, 4, LUA_DIRSEP));
+  if (f != NULL) return 1;
+  else {  /* error message is on top of the stack */
+    lua_pushnil(L);
+    lua_insert(L, -2);
+    return 2;  /* return nil + error message */
+  }
+}
+
+
+static const char *findfile (lua_State *L, const char *name,
+                                           const char *pname,
+                                           const char *dirsep) {
+  const char *path;
+  lua_getfield(L, lua_upvalueindex(1), pname);
+  path = lua_tostring(L, -1);
+  if (path == NULL)
+    luaL_error(L, "'package.%s' must be a string", pname);
+  return searchpath(L, name, path, ".", dirsep);
+}
+
+
+static int checkload (lua_State *L, int stat, const char *filename) {
+  if (stat) {  /* module loaded successfully? */
+    lua_pushstring(L, filename);  /* will be 2nd argument to module */
+    return 2;  /* return open function and file name */
+  }
+  else
+    return luaL_error(L, "error loading module '%s' from file '%s':\n\t%s",
+                          lua_tostring(L, 1), filename, lua_tostring(L, -1));
+}
+
+
+static int searcher_Lua (lua_State *L) {
+  const char *filename;
+  const char *name = luaL_checkstring(L, 1);
+  filename = findfile(L, name, "path", LUA_LSUBSEP);
+  if (filename == NULL) return 1;  /* module not found in this path */
+  return checkload(L, (luaL_loadfile(L, filename) == LUA_OK), filename);
+}
+
+
+/*
+** Try to find a load function for module 'modname' at file 'filename'.
+** First, change '.' to '_' in 'modname'; then, if 'modname' has
+** the form X-Y (that is, it has an "ignore mark"), build a function
+** name "luaopen_X" and look for it. (For compatibility, if that
+** fails, it also tries "luaopen_Y".) If there is no ignore mark,
+** look for a function named "luaopen_modname".
+*/
+static int loadfunc (lua_State *L, const char *filename, const char *modname) {
+  const char *openfunc;
+  const char *mark;
+  modname = luaL_gsub(L, modname, ".", LUA_OFSEP);
+  mark = strchr(modname, *LUA_IGMARK);
+  if (mark) {
+    int stat;
+    openfunc = lua_pushlstring(L, modname, mark - modname);
+    openfunc = lua_pushfstring(L, LUA_POF"%s", openfunc);
+    stat = lookforfunc(L, filename, openfunc);
+    if (stat != ERRFUNC) return stat;
+    modname = mark + 1;  /* else go ahead and try old-style name */
+  }
+  openfunc = lua_pushfstring(L, LUA_POF"%s", modname);
+  return lookforfunc(L, filename, openfunc);
+}
+
+
+static int searcher_C (lua_State *L) {
+  const char *name = luaL_checkstring(L, 1);
+  const char *filename = findfile(L, name, "cpath", LUA_CSUBSEP);
+  if (filename == NULL) return 1;  /* module not found in this path */
+  return checkload(L, (loadfunc(L, filename, name) == 0), filename);
+}
+
+
+static int searcher_Croot (lua_State *L) {
+  const char *filename;
+  const char *name = luaL_checkstring(L, 1);
+  const char *p = strchr(name, '.');
+  int stat;
+  if (p == NULL) return 0;  /* is root */
+  lua_pushlstring(L, name, p - name);
+  filename = findfile(L, lua_tostring(L, -1), "cpath", LUA_CSUBSEP);
+  if (filename == NULL) return 1;  /* root not found */
+  if ((stat = loadfunc(L, filename, name)) != 0) {
+    if (stat != ERRFUNC)
+      return checkload(L, 0, filename);  /* real error */
+    else {  /* open function not found */
+      lua_pushfstring(L, "\n\tno module '%s' in file '%s'", name, filename);
+      return 1;
+    }
+  }
+  lua_pushstring(L, filename);  /* will be 2nd argument to module */
+  return 2;
+}
+
+
+static int searcher_preload (lua_State *L) {
+  const char *name = luaL_checkstring(L, 1);
+  lua_getfield(L, LUA_REGISTRYINDEX, "_PRELOAD");
+  if (lua_getfield(L, -1, name) == LUA_TNIL)  /* not found? */
+    lua_pushfstring(L, "\n\tno field package.preload['%s']", name);
+  return 1;
+}
+
+
+static void findloader (lua_State *L, const char *name) {
+  int i;
+  luaL_Buffer msg;  /* to build error message */
+  luaL_buffinit(L, &msg);
+  /* push 'package.searchers' to index 3 in the stack */
+  if (lua_getfield(L, lua_upvalueindex(1), "searchers") != LUA_TTABLE)
+    luaL_error(L, "'package.searchers' must be a table");
+  /*  iterate over available searchers to find a loader */
+  for (i = 1; ; i++) {
+    if (lua_rawgeti(L, 3, i) == LUA_TNIL) {  /* no more searchers? */
+      lua_pop(L, 1);  /* remove nil */
+      luaL_pushresult(&msg);  /* create error message */
+      luaL_error(L, "module '%s' not found:%s", name, lua_tostring(L, -1));
+    }
+    lua_pushstring(L, name);
+    lua_call(L, 1, 2);  /* call it */
+    if (lua_isfunction(L, -2))  /* did it find a loader? */
+      return;  /* module loader found */
+    else if (lua_isstring(L, -2)) {  /* searcher returned error message? */
+      lua_pop(L, 1);  /* remove extra return */
+      luaL_addvalue(&msg);  /* concatenate error message */
+    }
+    else
+      lua_pop(L, 2);  /* remove both returns */
+  }
+}
+
+
+static int ll_require (lua_State *L) {
+  const char *name = luaL_checkstring(L, 1);
+  lua_settop(L, 1);  /* _LOADED table will be at index 2 */
+  lua_getfield(L, LUA_REGISTRYINDEX, "_LOADED");
+  lua_getfield(L, 2, name);  /* _LOADED[name] */
+  if (lua_toboolean(L, -1))  /* is it there? */
+    return 1;  /* package is already loaded */
+  /* else must load package */
+  lua_pop(L, 1);  /* remove 'getfield' result */
+  findloader(L, name);
+  lua_pushstring(L, name);  /* pass name as argument to module loader */
+  lua_insert(L, -2);  /* name is 1st argument (before search data) */
+  lua_call(L, 2, 1);  /* run loader to load module */
+  if (!lua_isnil(L, -1))  /* non-nil return? */
+    lua_setfield(L, 2, name);  /* _LOADED[name] = returned value */
+  if (lua_getfield(L, 2, name) == LUA_TNIL) {   /* module set no value? */
+    lua_pushboolean(L, 1);  /* use true as result */
+    lua_pushvalue(L, -1);  /* extra copy to be returned */
+    lua_setfield(L, 2, name);  /* _LOADED[name] = true */
+  }
+  return 1;
+}
+
+/* }====================================================== */
+
+
+
+/*
+** {======================================================
+** 'module' function
+** =======================================================
+*/
+#if defined(LUA_COMPAT_MODULE)
+
+/*
+** changes the environment variable of calling function
+*/
+static void set_env (lua_State *L) {
+  lua_Debug ar;
+  if (lua_getstack(L, 1, &ar) == 0 ||
+      lua_getinfo(L, "f", &ar) == 0 ||  /* get calling function */
+      lua_iscfunction(L, -1))
+    luaL_error(L, "'module' not called from a Lua function");
+  lua_pushvalue(L, -2);  /* copy new environment table to top */
+  lua_setupvalue(L, -2, 1);
+  lua_pop(L, 1);  /* remove function */
+}
+
+
+static void dooptions (lua_State *L, int n) {
+  int i;
+  for (i = 2; i <= n; i++) {
+    if (lua_isfunction(L, i)) {  /* avoid 'calling' extra info. */
+      lua_pushvalue(L, i);  /* get option (a function) */
+      lua_pushvalue(L, -2);  /* module */
+      lua_call(L, 1, 0);
+    }
+  }
+}
+
+
+static void modinit (lua_State *L, const char *modname) {
+  const char *dot;
+  lua_pushvalue(L, -1);
+  lua_setfield(L, -2, "_M");  /* module._M = module */
+  lua_pushstring(L, modname);
+  lua_setfield(L, -2, "_NAME");
+  dot = strrchr(modname, '.');  /* look for last dot in module name */
+  if (dot == NULL) dot = modname;
+  else dot++;
+  /* set _PACKAGE as package name (full module name minus last part) */
+  lua_pushlstring(L, modname, dot - modname);
+  lua_setfield(L, -2, "_PACKAGE");
+}
+
+
+static int ll_module (lua_State *L) {
+  const char *modname = luaL_checkstring(L, 1);
+  int lastarg = lua_gettop(L);  /* last parameter */
+  luaL_pushmodule(L, modname, 1);  /* get/create module table */
+  /* check whether table already has a _NAME field */
+  if (lua_getfield(L, -1, "_NAME") != LUA_TNIL)
+    lua_pop(L, 1);  /* table is an initialized module */
+  else {  /* no; initialize it */
+    lua_pop(L, 1);
+    modinit(L, modname);
+  }
+  lua_pushvalue(L, -1);
+  set_env(L);
+  dooptions(L, lastarg);
+  return 1;
+}
+
+
+static int ll_seeall (lua_State *L) {
+  luaL_checktype(L, 1, LUA_TTABLE);
+  if (!lua_getmetatable(L, 1)) {
+    lua_createtable(L, 0, 1); /* create new metatable */
+    lua_pushvalue(L, -1);
+    lua_setmetatable(L, 1);
+  }
+  lua_pushglobaltable(L);
+  lua_setfield(L, -2, "__index");  /* mt.__index = _G */
+  return 0;
+}
+
+#endif
+/* }====================================================== */
+
+
+
+/* auxiliary mark (for internal use) */
+#define AUXMARK		"\1"
+
+
+/*
+** return registry.LUA_NOENV as a boolean
+*/
+static int noenv (lua_State *L) {
+  int b;
+  lua_getfield(L, LUA_REGISTRYINDEX, "LUA_NOENV");
+  b = lua_toboolean(L, -1);
+  lua_pop(L, 1);  /* remove value */
+  return b;
+}
+
+
+static void setpath (lua_State *L, const char *fieldname, const char *envname1,
+                                   const char *envname2, const char *def) {
+  const char *path = getenv(envname1);
+  if (path == NULL)  /* no environment variable? */
+    path = getenv(envname2);  /* try alternative name */
+  if (path == NULL || noenv(L))  /* no environment variable? */
+    lua_pushstring(L, def);  /* use default */
+  else {
+    /* replace ";;" by ";AUXMARK;" and then AUXMARK by default path */
+    path = luaL_gsub(L, path, LUA_PATH_SEP LUA_PATH_SEP,
+                              LUA_PATH_SEP AUXMARK LUA_PATH_SEP);
+    luaL_gsub(L, path, AUXMARK, def);
+    lua_remove(L, -2);
+  }
+  setprogdir(L);
+  lua_setfield(L, -2, fieldname);
+}
+
+
+static const luaL_Reg pk_funcs[] = {
+  {"loadlib", ll_loadlib},
+  {"searchpath", ll_searchpath},
+#if defined(LUA_COMPAT_MODULE)
+  {"seeall", ll_seeall},
+#endif
+  /* placeholders */
+  {"preload", NULL},
+  {"cpath", NULL},
+  {"path", NULL},
+  {"searchers", NULL},
+  {"loaded", NULL},
+  {NULL, NULL}
+};
+
+
+static const luaL_Reg ll_funcs[] = {
+#if defined(LUA_COMPAT_MODULE)
+  {"module", ll_module},
+#endif
+  {"require", ll_require},
+  {NULL, NULL}
+};
+
+
+static void createsearcherstable (lua_State *L) {
+  static const lua_CFunction searchers[] =
+    {searcher_preload, searcher_Lua, searcher_C, searcher_Croot, NULL};
+  int i;
+  /* create 'searchers' table */
+  lua_createtable(L, sizeof(searchers)/sizeof(searchers[0]) - 1, 0);
+  /* fill it with predefined searchers */
+  for (i=0; searchers[i] != NULL; i++) {
+    lua_pushvalue(L, -2);  /* set 'package' as upvalue for all searchers */
+    lua_pushcclosure(L, searchers[i], 1);
+    lua_rawseti(L, -2, i+1);
+  }
+#if defined(LUA_COMPAT_LOADERS)
+  lua_pushvalue(L, -1);  /* make a copy of 'searchers' table */
+  lua_setfield(L, -3, "loaders");  /* put it in field 'loaders' */
+#endif
+  lua_setfield(L, -2, "searchers");  /* put it in field 'searchers' */
+}
+
+
+/*
+** create table CLIBS to keep track of loaded C libraries,
+** setting a finalizer to close all libraries when closing state.
+*/
+static void createclibstable (lua_State *L) {
+  lua_newtable(L);  /* create CLIBS table */
+  lua_createtable(L, 0, 1);  /* create metatable for CLIBS */
+  lua_pushcfunction(L, gctm);
+  lua_setfield(L, -2, "__gc");  /* set finalizer for CLIBS table */
+  lua_setmetatable(L, -2);
+  lua_rawsetp(L, LUA_REGISTRYINDEX, &CLIBS);  /* set CLIBS table in registry */
+}
+
+
+LUAMOD_API int luaopen_package (lua_State *L) {
+  createclibstable(L);
+  luaL_newlib(L, pk_funcs);  /* create 'package' table */
+  createsearcherstable(L);
+  /* set field 'path' */
+  setpath(L, "path", LUA_PATHVARVERSION, LUA_PATH_VAR, LUA_PATH_DEFAULT);
+  /* set field 'cpath' */
+  setpath(L, "cpath", LUA_CPATHVARVERSION, LUA_CPATH_VAR, LUA_CPATH_DEFAULT);
+  /* store config information */
+  lua_pushliteral(L, LUA_DIRSEP "\n" LUA_PATH_SEP "\n" LUA_PATH_MARK "\n"
+                     LUA_EXEC_DIR "\n" LUA_IGMARK "\n");
+  lua_setfield(L, -2, "config");
+  /* set field 'loaded' */
+  luaL_getsubtable(L, LUA_REGISTRYINDEX, "_LOADED");
+  lua_setfield(L, -2, "loaded");
+  /* set field 'preload' */
+  luaL_getsubtable(L, LUA_REGISTRYINDEX, "_PRELOAD");
+  lua_setfield(L, -2, "preload");
+  lua_pushglobaltable(L);
+  lua_pushvalue(L, -2);  /* set 'package' as upvalue for next lib */
+  luaL_setfuncs(L, ll_funcs, 1);  /* open lib into global table */
+  lua_pop(L, 1);  /* pop global table */
+  return 1;  /* return 'package' table */
+}
+