/*
- * The copyright in this software is being made available under the 2-clauses
- * BSD License, included below. This software may be subject to other third
+ * The copyright in this software is being made available under the 2-clauses
+ * BSD License, included below. This software may be subject to other third
* party and contributor rights, including patent rights, and no such rights
* are granted under this license.
*
#include "opj_includes.h"
#ifndef SIZE_MAX
-#define SIZE_MAX ((size_t) -1)
+# define SIZE_MAX ((size_t) -1)
#endif
static INLINE void *opj_aligned_alloc_n(size_t alignment, size_t size)
/* alignment shall be power of 2 */
assert( (alignment != 0U) && ((alignment & (alignment - 1U)) == 0U));
+ /* alignment shall be at least sizeof(void*) */
+ assert( alignment >= sizeof(void*));
if (size == 0U) { /* prevent implementation defined behavior of realloc */
return NULL;
}
-#if defined(HAVE_POSIX_MEMALIGN)
+#if defined(OPJ_HAVE_POSIX_MEMALIGN)
/* aligned_alloc requires c11, restrict to posix_memalign for now. Quote:
* This function was introduced in POSIX 1003.1d. Although this function is
* superseded by aligned_alloc, it is more portable to older POSIX systems
ptr = NULL;
}
/* older linux */
-#elif defined(HAVE_MEMALIGN)
+#elif defined(OPJ_HAVE_MEMALIGN)
ptr = memalign( alignment, size );
/* _MSC_VER */
-#elif defined(HAVE__ALIGNED_MALLOC)
+#elif defined(OPJ_HAVE__ALIGNED_MALLOC)
ptr = _aligned_malloc(size, alignment);
#else
/*
* Generic aligned malloc implementation.
- * Uses ptrdiff_t for the integer manipulation of the pointer, as
- * uintptr_t is not available in C89.
+ * Uses size_t offset for the integer manipulation of the pointer,
+ * as uintptr_t is not available in C89 to do
+ * bitwise operations on the pointer itself.
*/
+ alignment--;
{
- ptrdiff_t mask;
- void *mem;
+ size_t offset;
+ OPJ_UINT8 *mem;
/* Room for padding and extra pointer stored in front of allocated area */
- size_t overhead = (alignment - 1) + sizeof(void *);
+ size_t overhead = alignment + sizeof(void *);
+
+ /* let's be extra careful */
+ assert(alignment <= (SIZE_MAX - sizeof(void *)));
/* Avoid integer overflow */
- if (size > SIZE_MAX - overhead)
+ if (size > (SIZE_MAX - overhead)) {
return NULL;
+ }
- mem = malloc(size + overhead);
- if (!mem)
+ mem = (OPJ_UINT8*)malloc(size + overhead);
+ if (mem == NULL) {
return mem;
-
- mask = ~(ptrdiff_t)(alignment - 1);
- ptr = (void *) ((ptrdiff_t) (mem + overhead) & mask);
+ }
+ /* offset = ((alignment + 1U) - ((size_t)(mem + sizeof(void*)) & alignment)) & alignment; */
+ /* Use the fact that alignment + 1U is a power of 2 */
+ offset = ((alignment ^ ((size_t)(mem + sizeof(void*)) & alignment)) + 1U) & alignment;
+ ptr = (void *)(mem + sizeof(void*) + offset);
((void**) ptr)[-1] = mem;
}
#endif
/* alignment shall be power of 2 */
assert( (alignment != 0U) && ((alignment & (alignment - 1U)) == 0U));
+ /* alignment shall be at least sizeof(void*) */
+ assert( alignment >= sizeof(void*));
if (new_size == 0U) { /* prevent implementation defined behavior of realloc */
return NULL;
}
/* no portable aligned realloc */
-#if defined(HAVE_POSIX_MEMALIGN) || defined(HAVE_MEMALIGN)
- /* glibc doc states one can mixed aligned malloc with realloc */
+#if defined(OPJ_HAVE_POSIX_MEMALIGN) || defined(OPJ_HAVE_MEMALIGN)
+ /* glibc doc states one can mix aligned malloc with realloc */
r_ptr = realloc( ptr, new_size ); /* fast path */
/* we simply use `size_t` to cast, since we are only interest in binary AND
* operator */
r_ptr = a_ptr;
}
/* _MSC_VER */
-#elif defined(HAVE__ALIGNED_MALLOC)
+#elif defined(OPJ_HAVE__ALIGNED_MALLOC)
r_ptr = _aligned_realloc( ptr, new_size, alignment );
#else
+ if (ptr == NULL) {
+ return opj_aligned_alloc_n(alignment, new_size);
+ }
+ alignment--;
{
- void *oldmem, *newmem;
- size_t overhead = (alignment - 1) + sizeof(void *);
-
- if (new_size == 0) {
- my_aligned_free(ptr);
- return NULL;
- }
+ void *oldmem;
+ OPJ_UINT8 *newmem;
+ size_t overhead = alignment + sizeof(void *);
+
+ /* let's be extra careful */
+ assert(alignment <= (SIZE_MAX - sizeof(void *)));
/* Avoid integer overflow */
- if (new_size > SIZE_MAX - overhead)
+ if (new_size > SIZE_MAX - overhead) {
return NULL;
+ }
oldmem = ((void**) ptr)[-1];
- newmem = realloc(oldmem, new_size + overhead);
- if (!newmem)
+ newmem = (OPJ_UINT8*)realloc(oldmem, new_size + overhead);
+ if (newmem == NULL) {
return newmem;
+ }
if (newmem == oldmem) {
r_ptr = ptr;
}
else {
- ptrdiff_t old_offset, new_offset;
- ptrdiff_t mask;
+ size_t old_offset;
+ size_t new_offset;
/* realloc created a new copy, realign the copied memory block */
- old_offset = (char *) ptr - (char *) oldmem;
-
- mask = ~(ptrdiff_t)(alignment - 1);
- r_ptr = (void *) ((ptrdiff_t) (newmem + overhead) & mask);
+ old_offset = (size_t)((OPJ_UINT8*)ptr - (OPJ_UINT8*)oldmem);
- new_offset = (char *) r_ptr - (char *) newmem;
+ /* offset = ((alignment + 1U) - ((size_t)(mem + sizeof(void*)) & alignment)) & alignment; */
+ /* Use the fact that alignment + 1U is a power of 2 */
+ new_offset = ((alignment ^ ((size_t)(newmem + sizeof(void*)) & alignment)) + 1U) & alignment;
+ new_offset += sizeof(void*);
+ r_ptr = (void *)(newmem + new_offset);
if (new_offset != old_offset) {
- memmove((char *) newmem + new_offset, (char *) newmem + old_offset,
- new_size);
+ memmove(newmem + new_offset, newmem + old_offset, new_size);
}
((void**) r_ptr)[-1] = newmem;
}
void opj_aligned_free(void* ptr)
{
-#if defined(HAVE_POSIX_MEMALIGN) || defined(HAVE_MEMALIGN)
+#if defined(OPJ_HAVE_POSIX_MEMALIGN) || defined(OPJ_HAVE_MEMALIGN)
free( ptr );
-#elif defined(HAVE__ALIGNED_MALLOC)
+#elif defined(OPJ_HAVE__ALIGNED_MALLOC)
_aligned_free( ptr );
#else
/* Generic implementation has malloced pointer stored in front of used area */
- if (ptr)
+ if (ptr != NULL) {
free(((void**) ptr)[-1]);
+ }
#endif
}
projects / openjpeg.git / blobdiff