diff --git a/freelist/Makefile b/freelist/Makefile index 9d85953..7f6d8a6 100644 --- a/freelist/Makefile +++ b/freelist/Makefile @@ -1,8 +1,6 @@ CC = gcc CFLAGS = -Wall -O2 -CFLAGS += -DFREELIST_NOALIGN - TARGET = main.elf SRC = main.c freelist.c diff --git a/freelist/freelist.c b/freelist/freelist.c index 380010f..9b47a8d 100644 --- a/freelist/freelist.c +++ b/freelist/freelist.c @@ -4,11 +4,23 @@ #include #include #include -#include + +/* Fiddle these around according to your need. */ +#ifdef FREELIST_NOALIGN +#define ALIGN(x) (x) +#else // FREELIST_NOALIGN + +/* Align to nearest multiple of sizeof(void*) */ +static inline size_t align_up(size_t n) { + return (n + sizeof(void *) - 1) & ~(sizeof(void *) - 1); +} + +#define ALIGN(x) (align_up(x)) +#endif // FREELIST_NOALIGN /* Initialize the FreeList */ int fl_init(FreeList *fl, uintptr_t start, uintptr_t end, size_t itemsize) { - size_t size = ALIGN(itemsize); + size_t size = ALIGN(itemsize + sizeof(FreeListBlock)); if (!fl || end <= start) return EXIT_FAILURE; @@ -40,8 +52,7 @@ void *fl_alloc(FreeList *fl) { fl->free = fl->free->next; fl->allocated++; - memset((void *)m, 0, sizeof(FreeListBlock)); - return ((void *)m); + return ((void *)m) + sizeof(FreeListBlock); } /* Return some memory to the FreeList */ @@ -50,7 +61,7 @@ int fl_free(FreeList *fl, void *ptr) { return EXIT_FAILURE; /* We cant free memory we do not own */ } - FreeListBlock *block = (FreeListBlock *)(uintptr_t)ptr; + FreeListBlock *block = (FreeListBlock *)((uintptr_t)ptr - sizeof(FreeListBlock)); block->next = fl->free; fl->free = block; diff --git a/freelist/freelist.h b/freelist/freelist.h index f0e8ed4..de12d5d 100644 --- a/freelist/freelist.h +++ b/freelist/freelist.h @@ -5,19 +5,6 @@ #include #include -/* Fiddle these around according to your need. Delete or check makefile */ -#ifdef FREELIST_NOALIGN -#define ALIGN(x) (x) -#else // FREELIST_NOALIGN - -/* Align to nearest multiple of sizeof(void*) */ -static inline size_t align_up(size_t n) { - return (n + sizeof(void *) - 1) & ~(sizeof(void *) - 1); -} - -#define ALIGN(x) (align_up(x)) -#endif // FREELIST_NOALIGN - #define FL_FREE ((uint8_t)0x00) #define FL_USED ((uint8_t)0x01) diff --git a/freelist/main.c b/freelist/main.c index 49aa19b..0841d2e 100644 --- a/freelist/main.c +++ b/freelist/main.c @@ -17,21 +17,16 @@ void printvec(const Vec3 *v) { printf("Vec3: (%d, %d, %d)\n", v->x, v->y, v->z); } -#define BUFFER_SIZE (4096) - int main() { - FreeList fl; - const char *mem = malloc(BUFFER_SIZE); - - fl_init(&fl, (uintptr_t)mem, (uintptr_t)mem + BUFFER_SIZE, sizeof(Vec3)); - const size_t cap = fl_capacity(&fl); - - printf("Item size: %lu\n", sizeof(Vec3)); - printf("Buffer size: %d\n", BUFFER_SIZE); - printf("Space utilization internal: %.2f%%\n", 100.0 * fl_utilization(&fl, sizeof(Vec3))); + FreeList fl; + char *mem = malloc(4096); + fl_init(&fl, (uintptr_t)mem, (uintptr_t)mem + 4096, sizeof(Vec3)); + size_t cap = fl_capacity(&fl); assert(fl_available(&fl) == cap); + printf("Space utilization: %.2f%%\n", 100.0 * fl_utilization(&fl, sizeof(Vec3))); + Vec3 *a = fl_alloc(&fl); Vec3 *b = fl_alloc(&fl); Vec3 *c = fl_alloc(&fl);