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-rw-r--r--Source/Kernel/MemoryManager/Heap.class.cpp212
1 files changed, 0 insertions, 212 deletions
diff --git a/Source/Kernel/MemoryManager/Heap.class.cpp b/Source/Kernel/MemoryManager/Heap.class.cpp
deleted file mode 100644
index 365b4f0..0000000
--- a/Source/Kernel/MemoryManager/Heap.class.cpp
+++ /dev/null
@@ -1,212 +0,0 @@
-#include "Heap.class.h"
-#include <MemoryManager/PageDirectory.class.h>
-
-Heap::Heap() : m_mutex(MUTEX_FALSE) {
- m_usable = false;
- m_index.data = 0;
- m_index.size = 0;
-}
-
-Heap::~Heap() {
- //TODO (optionnal) : free pages.
-}
-
-void Heap::create(u32int start, u32int size, u32int idxsize, PageDirectory* pagedir, bool user, bool rw) {
- if (m_usable) return;
-
- if (start & 0x0FFF) start = (start & 0xFFFFF000) + 0x1000;
- if (size & 0x0FFF) size = (size & 0xFFFFF000) + 0x1000;
- m_start = start + idxsize; //m_start is start of real data, start is start of index.
- m_end = start + size;
-
- m_pagedir = pagedir;
- m_user = user;
- m_rw = rw;
-
- //Allocate frames for heap
- for (u32int i = start ; i < m_end; i += 0x1000) {
- m_pagedir->allocFrame(i, m_user, m_rw);
- }
- m_pagedir->switchTo();
-
- m_index.data = (heap_header_t **)start; //Set index start. start == start of all heap
- m_index.size = 0;
-
- heap_header_t *hole = (heap_header_t*) m_start; //m_start == start of data
- hole->size = (m_end - m_start);
- hole->magic = HEAP_MAGIC;
- hole->is_hole = true;
-
- heap_footer_t *hole_footer = (heap_footer_t*) (m_end - sizeof(heap_footer_t));
- hole_footer->header = hole;
- hole_footer->magic = HEAP_MAGIC;
-
- insertIntoIndex(hole);
-
- m_usable = true;
- m_free = (m_end - m_start);
-
- m_mutex.unlock();
-}
-
-void Heap::expand(u32int quantity) {
- if (quantity & 0x00000FFF)
- quantity = (quantity & 0xFFFFF000) + 0x1000;
-
- u32int newEnd = m_end + quantity;
-
- for (u32int i = m_end; i < newEnd; i++) {
- m_pagedir->allocFrame(i, m_user, m_rw);
- }
-
- heap_footer_t *last_footer = (heap_footer_t*) (m_end - sizeof(heap_footer_t));
- heap_header_t *last_header = last_footer->header;
- if (last_header->is_hole) { //Last block of heap is a hole, update its size
- removeFromIndex(last_header);
- last_header->size += quantity;
-
- last_footer = (heap_footer_t*) (newEnd - sizeof(heap_footer_t));
-
- last_footer->magic = HEAP_MAGIC;
- last_footer->header = last_header;
-
- insertIntoIndex(last_header);
- } else { //Last block is not a hole. Just add a new hole at the end
- last_header = (heap_header_t*)m_end;
- last_footer = (heap_footer_t*) (newEnd - sizeof(heap_footer_t));
-
- last_header->is_hole = true;
- last_header->magic = HEAP_MAGIC;
- last_header->size = quantity;
-
- last_footer->magic = HEAP_MAGIC;
- last_footer->header = last_header;
-
- insertIntoIndex(last_header);
- }
-
- m_end = newEnd;
- m_free += quantity;
-}
-
-void Heap::contract() { //Automatically work out how much we can contract
- heap_footer_t *last_footer = (heap_footer_t*) (m_end - sizeof(heap_footer_t));
- heap_header_t *last_header = last_footer->header;
- if (last_header->is_hole == false) return; //We need a hole at end of heap
-
- u32int quantity = 0;
- while ((m_end - m_start) - quantity > HEAP_MIN_SIZE and
- (last_header->size - quantity) > 0x1000) //Always keep at least 0x1000 free at end
- quantity += 0x1000;
- if (quantity == 0) return;
-
- u32int newEnd = m_end - quantity;
- m_free -= quantity;
-
- removeFromIndex(last_header);
- last_header->size -= quantity;
- last_footer = (heap_footer_t*)((u32int)last_footer - quantity);
- last_footer->magic = HEAP_MAGIC;
- last_footer->header = last_header;
- insertIntoIndex(last_header);
-
- for (u32int i = newEnd; i < m_end; i += 0x1000) {
- m_pagedir->freeFrame(i);
- }
-
- m_end = newEnd;
-}
-
-void *Heap::alloc(u32int sz, bool no_expand) {
- m_mutex.waitLock();
-
- u32int newsize = sz + sizeof(heap_header_t) + sizeof(heap_footer_t);
- u32int iterator = 0;
- while (iterator < m_index.size) {
- if (m_index.data[iterator]->size >= newsize) break;
- iterator++;
- }
- if (iterator == m_index.size) { //No hole is big enough
- if (no_expand) {
- m_mutex.unlock();
- return 0;
- }
- expand((sz & 0xFFFFF000) + 0x1000);
- m_mutex.unlock();
- return alloc(sz, true); //Recurse call
- }
-
- heap_header_t *loc = m_index.data[iterator];
- heap_footer_t *footer = (heap_footer_t*)((u32int)loc + loc->size - sizeof(heap_footer_t));
- loc->is_hole = false; //Update current header
-
- removeFromIndex(loc);
-
- //Here we create a new hole after currently allocated block, but only if we have enough space. If we don't, we simply allocate a bigger block so that we don't loose space
- if (loc->size > (newsize + sizeof(heap_header_t) + sizeof(heap_footer_t))) {
- loc->size = newsize; //Update header for return block
-
- heap_footer_t *newfooter = (heap_footer_t*)((u32int)loc + newsize - sizeof(heap_footer_t)); //Write footer for return block
- newfooter->header = loc;
- newfooter->magic = HEAP_MAGIC;
-
- heap_header_t *nextloc = (heap_header_t*)((u32int)loc + newsize); //Write header for new hole
- nextloc->is_hole = true;
- nextloc->magic = HEAP_MAGIC;
- nextloc->size = ((u32int)footer - (u32int)nextloc + sizeof(heap_footer_t));
-
- footer->header = nextloc; //Write footer for new hole
- footer->magic = HEAP_MAGIC;
-
- insertIntoIndex(nextloc);
- }
-
- m_free -= loc->size;
-
- m_mutex.unlock();
-
- return (void*)((u32int)loc + sizeof(heap_header_t));
-}
-
-void Heap::free(void *ptr) {
- if (ptr == 0) return;
-
- heap_header_t *header = (heap_header_t*) ((u32int)ptr - sizeof(heap_header_t));
- heap_footer_t *footer = (heap_footer_t*)((u32int)header + header->size - sizeof(heap_footer_t));
- if (header->magic != HEAP_MAGIC or footer->magic != HEAP_MAGIC) return;
-
- m_mutex.waitLock();
-
- m_free += header->size;
-
- //Unify left
- heap_footer_t *prev_footer = (heap_footer_t*)((u32int)header - sizeof(heap_footer_t));
- if (prev_footer->magic == HEAP_MAGIC && prev_footer->header->is_hole) {
- header = prev_footer->header;
- removeFromIndex(header);
-
- footer->header = header;
- header->size = ((u32int)footer - (u32int)header + sizeof(heap_footer_t));
- }
-
- //Unify right
- heap_header_t *next_header = (heap_header_t*)((u32int)footer + sizeof(heap_footer_t));
- if (next_header->magic == HEAP_MAGIC && next_header->is_hole) {
- removeFromIndex(next_header);
- footer = (heap_footer_t*)((u32int)footer + next_header->size);
-
- footer->header = header;
- header->size = ((u32int)footer - (u32int)header + sizeof(heap_footer_t));
- }
-
- header->is_hole = true;
-
- insertIntoIndex(header);
-
- if ((u32int)footer == (m_end - sizeof(heap_footer_t)) and
- header->size >= 0x2000 and (m_end - m_start > HEAP_MIN_SIZE)) {
- contract();
- }
-
- m_mutex.unlock();
-}