diff options
Diffstat (limited to 'src/malloc')
-rw-r--r-- | src/malloc/aligned_alloc.c | 51 | ||||
-rw-r--r-- | src/malloc/memalign.c | 8 | ||||
-rw-r--r-- | src/malloc/posix_memalign.c | 43 |
3 files changed, 55 insertions, 47 deletions
diff --git a/src/malloc/aligned_alloc.c b/src/malloc/aligned_alloc.c new file mode 100644 index 00000000..d623420b --- /dev/null +++ b/src/malloc/aligned_alloc.c @@ -0,0 +1,51 @@ +#include <stdlib.h> +#include <stdint.h> +#include <errno.h> + +/* This function should work with most dlmalloc-like chunk bookkeeping + * systems, but it's only guaranteed to work with the native implementation + * used in this library. */ + +void *aligned_alloc(size_t align, size_t len) +{ + unsigned char *mem, *new, *end; + size_t header, footer; + + if ((align & -align & -sizeof(void *)) != align) { + errno = EINVAL; + return NULL; + } + + if (len > SIZE_MAX - align) { + errno = ENOMEM; + return NULL; + } + + if (align <= 4*sizeof(size_t)) { + if (!(mem = malloc(len))) + return NULL; + return mem; + } + + if (!(mem = malloc(len + align-1))) + return NULL; + + header = ((size_t *)mem)[-1]; + end = mem + (header & -8); + footer = ((size_t *)end)[-2]; + new = (void *)((uintptr_t)mem + align-1 & -align); + + if (!(header & 7)) { + ((size_t *)new)[-2] = ((size_t *)mem)[-2] + (new-mem); + ((size_t *)new)[-1] = ((size_t *)mem)[-1] - (new-mem); + return new; + } + + ((size_t *)mem)[-1] = header&7 | new-mem; + ((size_t *)new)[-2] = footer&7 | new-mem; + ((size_t *)new)[-1] = header&7 | end-new; + ((size_t *)end)[-2] = footer&7 | end-new; + + if (new != mem) free(mem); + return new; +} diff --git a/src/malloc/memalign.c b/src/malloc/memalign.c index 61f456e4..a594c636 100644 --- a/src/malloc/memalign.c +++ b/src/malloc/memalign.c @@ -3,11 +3,5 @@ void *memalign(size_t align, size_t len) { - void *mem; - int ret; - if ((ret = posix_memalign(&mem, align, len))) { - errno = ret; - return 0; - } - return mem; + return aligned_alloc(align, len); } diff --git a/src/malloc/posix_memalign.c b/src/malloc/posix_memalign.c index 2ae928c8..42cf2740 100644 --- a/src/malloc/posix_memalign.c +++ b/src/malloc/posix_memalign.c @@ -1,47 +1,10 @@ #include <stdlib.h> -#include <stdint.h> #include <errno.h> -/* This function should work with most dlmalloc-like chunk bookkeeping - * systems, but it's only guaranteed to work with the native implementation - * used in this library. */ - int posix_memalign(void **res, size_t align, size_t len) { - unsigned char *mem, *new, *end; - size_t header, footer; - - if ((align & -align & -sizeof(void *)) != align) return EINVAL; - if (len > SIZE_MAX - align) return ENOMEM; - - if (align <= 4*sizeof(size_t)) { - if (!(mem = malloc(len))) - return errno; - *res = mem; - return 0; - } - - if (!(mem = malloc(len + align-1))) - return errno; - - header = ((size_t *)mem)[-1]; - end = mem + (header & -8); - footer = ((size_t *)end)[-2]; - new = (void *)((uintptr_t)mem + align-1 & -align); - - if (!(header & 7)) { - ((size_t *)new)[-2] = ((size_t *)mem)[-2] + (new-mem); - ((size_t *)new)[-1] = ((size_t *)mem)[-1] - (new-mem); - *res = new; - return 0; - } - - ((size_t *)mem)[-1] = header&7 | new-mem; - ((size_t *)new)[-2] = footer&7 | new-mem; - ((size_t *)new)[-1] = header&7 | end-new; - ((size_t *)end)[-2] = footer&7 | end-new; - - if (new != mem) free(mem); - *res = new; + void *mem = aligned_alloc(align, len); + if (!mem) return errno; + *res = mem; return 0; } |