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/* See LICENSE file for copyright and license details. */
#include "libsimple.h"
#include "test.h"
#include <malloc.h>
#undef strndup
#undef memdup
size_t alloc_fail_in = 0;
static int custom_malloc = 0;
size_t
get_pagesize(void)
{
long r;
assert((r = sysconf(_SC_PAGESIZE)) >= 0);
return (size_t)r;
}
size_t
round_up(size_t size)
{
size_t ps = get_pagesize();
return size + (ps - size % ps) % ps;
}
int
have_custom_malloc(void)
{
free(malloc(1));
return custom_malloc;
}
struct allocinfo *
get_allocinfo(void *ptr)
{
assert(ptr);
return (void *)((char *)ptr - sizeof(struct allocinfo));
}
void *
malloc(size_t size)
{
size_t alignment = get_pagesize();
while (alignment < sizeof(long long int))
alignment *= 2;
while (alignment < sizeof(long double))
alignment *= 2;
return memalign(alignment, size);
}
void *
calloc(size_t nelem, size_t elsize)
{
struct allocinfo *info;
void *ret;
assert(nelem && elsize); /* unspecified behaviour otherwise */
if (nelem > SIZE_MAX / elsize) {
errno = ENOMEM;
return NULL;
}
ret = malloc(nelem * elsize);
if (!ret)
return NULL;
memset(ret, 0, nelem * elsize);
info = get_allocinfo(ret);
info->zeroed = nelem * elsize;
return ret;
}
void *
realloc(void *ptr, size_t size)
{
struct allocinfo *info;
void *ret;
size_t n;
assert(size); /* unspecified behaviour otherwise */
if (!ptr)
return malloc(size);
ret = malloc(size);
if (!ret)
return malloc;
info = get_allocinfo(ret);
n = MIN(size, info->size);
info->zeroed = MIN(n, info->zeroed);
memcpy(ret, ptr, n);
free(ptr);
return ret;
}
void *
memalign(size_t alignment, size_t size)
{
struct allocinfo *info;
void *ptr;
size_t n;
uintptr_t off;
custom_malloc = 1;
assert(alignment);
assert(!(alignment & (alignment - 1UL)));
assert(size); /* unspecified behaviour otherwise */
if (alloc_fail_in && alloc_fail_in-- == 1)
goto enomem;
n = size;
if (n > SIZE_MAX - alignment)
goto enomem;
n += alignment;
if (n > SIZE_MAX - sizeof(struct allocinfo))
goto enomem;
n += sizeof(struct allocinfo);
ptr = mmap(NULL, n, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (!ptr)
goto enomem;
off = (uintptr_t)ptr;
off += sizeof(struct allocinfo);
off += (alignment - off % alignment) % alignment;
off -= (uintptr_t)ptr;
ptr = (char *)ptr + off;
info = get_allocinfo(ptr);
info->real_beginning = (char *)ptr - off;
info->real_size = n;
info->size = size;
info->extent = n - size - off;
info->alignment = alignment;
info->zeroed = 0;
info->refcount = 1;
return ptr;
enomem:
errno = ENOMEM;
return NULL;
}
int
posix_memalign(void **memptr, size_t alignment, size_t size)
{
int ret, saved_errno = errno;
void **volatile ptrp = memptr;
assert(!(alignment % sizeof(void *)));
assert(ptrp);
*memptr = memalign(alignment, size);
ret = *memptr ? ENOMEM : 0;
errno = saved_errno;
return ret;
}
void *
aligned_alloc(size_t alignment, size_t size)
{
assert(alignment);
assert(!(size % alignment));
return memalign(alignment, size);
}
void *
valloc(size_t size)
{
return memalign(get_pagesize(), size);
}
void *
pvalloc(size_t size)
{
return memalign(get_pagesize(), round_up(size));
}
char *
strdup(const char *s)
{
char *r = malloc(strlen(s) + 1);
return r ? strcpy(r, s) : r;
}
char *
strndup(const char *s, size_t size)
{
return libsimple_strndup(s, size);
}
void *
memdup(const void *s, size_t size)
{
return libsimple_memdup(s, size);
}
void
free(void *ptr)
{
struct allocinfo *info;
if (!ptr)
return;
info = get_allocinfo(ptr);
assert(info->refcount);
if (info->refcount-- > 1)
return;
assert(!munmap(info->real_beginning, info->real_size));
}
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