diff options
Diffstat (limited to 'src/heap.c')
| -rw-r--r-- | src/heap.c | 167 |
1 files changed, 0 insertions, 167 deletions
diff --git a/src/heap.c b/src/heap.c deleted file mode 100644 index 9b86ad6..0000000 --- a/src/heap.c +++ /dev/null @@ -1,167 +0,0 @@ -#include"types.h" - -/* - 2014 Leonard Kevin McGuire Jr (www.kmcg3413.net) (kmcg3413@gmail.com) - 2016 Clément Gallet (provided bug fixes) -*/ -typedef struct _KHEAPBLOCKBM { - struct _KHEAPBLOCKBM *next; - uint32_t size; - uint32_t used; - uint32_t bsize; - uint32_t lfb; -} KHEAPBLOCKBM; - -typedef struct _KHEAPBM { - KHEAPBLOCKBM *fblock; -} KHEAPBM; - -void k_heapBMInit(KHEAPBM *heap) { - heap->fblock = 0; -} - -int k_heapBMAddBlock(KHEAPBM *heap, uintptr_t addr, uint32_t size, uint32_t bsize) { - KHEAPBLOCKBM *b; - uint32_t bcnt; - uint32_t x; - uint8_t *bm; - - b = (KHEAPBLOCKBM*)addr; - b->size = size - sizeof(KHEAPBLOCKBM); - b->bsize = bsize; - - b->next = heap->fblock; - heap->fblock = b; - - bcnt = b->size / b->bsize; - bm = (uint8_t*)&b[1]; - - /* clear bitmap */ - for (x = 0; x < bcnt; ++x) { - bm[x] = 0; - } - - /* reserve room for bitmap */ - bcnt = (bcnt / bsize) * bsize < bcnt ? bcnt / bsize + 1 : bcnt / bsize; - for (x = 0; x < bcnt; ++x) { - bm[x] = 5; - } - - b->lfb = bcnt - 1; - - b->used = bcnt; - - return 1; -} - -static uint8_t k_heapBMGetNID(uint8_t a, uint8_t b) { - uint8_t c; - for (c = a + 1; c == b || c == 0; ++c); - return c; -} - -void *k_heapBMAlloc(KHEAPBM *heap, uint32_t size) { - KHEAPBLOCKBM *b; - uint8_t *bm; - uint32_t bcnt; - uint32_t x, y, z; - uint32_t bneed; - uint8_t nid; - - /* iterate blocks */ - for (b = heap->fblock; b; b = b->next) { - /* check if block has enough room */ - if (b->size - (b->used * b->bsize) >= size) { - - bcnt = b->size / b->bsize; - bneed = (size / b->bsize) * b->bsize < size ? size / b->bsize + 1 : size / b->bsize; - bm = (uint8_t*)&b[1]; - - for (x = (b->lfb + 1 >= bcnt ? 0 : b->lfb + 1); x < b->lfb; ++x) { - /* just wrap around */ - if (x >= bcnt) { - x = 0; - } - - if (bm[x] == 0) { - /* count free blocks */ - for (y = 0; bm[x + y] == 0 && y < bneed && (x + y) < bcnt; ++y); - - /* we have enough, now allocate them */ - if (y == bneed) { - /* find ID that does not match left or right */ - nid = k_heapBMGetNID(bm[x - 1], bm[x + y]); - - /* allocate by setting id */ - for (z = 0; z < y; ++z) { - bm[x + z] = nid; - } - - /* optimization */ - b->lfb = (x + bneed) - 2; - - /* count used blocks NOT bytes */ - b->used += y; - - return (void*)(x * b->bsize + (uintptr_t)&b[1]); - } - - /* x will be incremented by one ONCE more in our FOR loop */ - x += (y - 1); - continue; - } - } - } - } - - return 0; -} - -void k_heapBMFree(KHEAPBM *heap, void *ptr) { - KHEAPBLOCKBM *b; - uintptr_t ptroff; - uint32_t bi, x; - uint8_t *bm; - uint8_t id; - uint32_t max; - - for (b = heap->fblock; b; b = b->next) { - if ((uintptr_t)ptr > (uintptr_t)b && (uintptr_t)ptr < (uintptr_t)b + sizeof(KHEAPBLOCKBM) + b->size) { - /* found block */ - ptroff = (uintptr_t)ptr - (uintptr_t)&b[1]; /* get offset to get block */ - /* block offset in BM */ - bi = ptroff / b->bsize; - /* .. */ - bm = (uint8_t*)&b[1]; - /* clear allocation */ - id = bm[bi]; - /* oddly.. GCC did not optimize this */ - max = b->size / b->bsize; - for (x = bi; bm[x] == id && x < max; ++x) { - bm[x] = 0; - } - /* update free block count */ - b->used -= x - bi; - return; - } - } - - /* this error needs to be raised or reported somehow */ - return; -} - -KHEAPBM kheap; - -void heap() -{ - KHEAPBM kheap; - char *ptr; - - k_heapBMInit(&kheap); /* initialize the heap */ - k_heapBMAddBlock(&kheap, 0x100000, 0x100000, 16); /* add block to heap - (starting 1MB mark and length of 1MB) - with default block size of 16 bytes - */ - ptr = (char*)k_heapBMAlloc(&kheap, 256); /* allocate 256 bytes (malloc) */ - k_heapBMFree(&kheap, ptr); /* free the pointer (free) */ -} |