51 lines
1.1 KiB
C++
51 lines
1.1 KiB
C++
|
#include "KernelHeap.h"
|
||
|
|
|
||
|
|
// Size of heap meta data is 5 bytes
|
||
|
|
struct heap_block{
|
||
|
|
uint8_t Used;
|
||
|
|
uint32_t Size;
|
||
|
|
}
|
||
|
|
|
||
|
|
uint32_t heap_size;
|
||
|
|
heap_block* start ;
|
||
|
|
|
||
|
|
void* malloc(size_t size)
|
||
|
|
{
|
||
|
|
printf("Received request for %d bytes of memory", size);
|
||
|
|
heap_block* current = start;
|
||
|
|
|
||
|
|
while(current < start + heap_size)
|
||
|
|
{
|
||
|
|
if(current->size >= size && current->Used == false )
|
||
|
|
{
|
||
|
|
// We found a spot
|
||
|
|
// Set the spot to in-use
|
||
|
|
current->Used = false;
|
||
|
|
// return the free address
|
||
|
|
// NOTE: added an offset from the initial address to accomodate for
|
||
|
|
// meta-data.
|
||
|
|
return current + sizeof(heap_block);
|
||
|
|
|
||
|
|
}
|
||
|
|
|
||
|
|
current += current->Size + sizeof(heap_block);
|
||
|
|
}
|
||
|
|
|
||
|
|
// If we are here we need more memory so we should
|
||
|
|
// probably ask the VMM for more
|
||
|
|
// TODO: ask for more memory
|
||
|
|
|
||
|
|
}
|
||
|
|
|
||
|
|
void free(void* addr)
|
||
|
|
{
|
||
|
|
// clear the free boolean that corresponds to this adddress
|
||
|
|
// This should be fairly simple
|
||
|
|
heap_block* allocatedBlock = addr - sizeof(heap_block);
|
||
|
|
allocate_block->Used = false;
|
||
|
|
}
|
||
|
|
|
||
|
|
void initHeap()
|
||
|
|
{
|
||
|
|
|
||
|
|
}
|