/*
- * 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.
*
#define OPJ_SKIP_POISON
#include "opj_includes.h"
+#ifndef SIZE_MAX
+# define SIZE_MAX ((size_t) -1)
+#endif
+
static INLINE void *opj_aligned_alloc_n(size_t alignment, size_t size)
{
void* ptr;
/* 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* superseded by aligned_alloc, it is more portable to older POSIX systems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
-/* TODO: _mm_malloc(x,y) */
-#error missing aligned alloc function
+ /*
+ * Generic aligned malloc implementation.
+ * 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--;
+ {
+ size_t offset;
+ OPJ_UINT8 *mem;
+
+ /* Room for padding and extra pointer stored in front of allocated area */
+ 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)) {
+ return NULL;
+ }
+
+ mem = (OPJ_UINT8*)malloc(size + overhead);
+ if (mem == NULL) {
+ return mem;
+ }
+ /* 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
return ptr;
}
/* 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
-/* TODO: _mm_malloc(x,y) */
-#error missing aligned realloc function
+ if (ptr == NULL) {
+ return opj_aligned_alloc_n(alignment, new_size);
+ }
+ alignment--;
+ {
+ 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) {
+ return NULL;
+ }
+
+ oldmem = ((void**) ptr)[-1];
+ newmem = (OPJ_UINT8*)realloc(oldmem, new_size + overhead);
+ if (newmem == NULL) {
+ return newmem;
+ }
+
+ if (newmem == oldmem) {
+ r_ptr = ptr;
+ }
+ else {
+ size_t old_offset;
+ size_t new_offset;
+
+ /* realloc created a new copy, realign the copied memory block */
+ old_offset = (size_t)((OPJ_UINT8*)ptr - (OPJ_UINT8*)oldmem);
+
+ /* 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(newmem + new_offset, newmem + old_offset, new_size);
+ }
+ ((void**) r_ptr)[-1] = newmem;
+ }
+ }
#endif
return r_ptr;
}
void opj_aligned_free(void* ptr)
{
-#ifdef HAVE__ALIGNED_MALLOC
+#if defined(OPJ_HAVE_POSIX_MEMALIGN) || defined(OPJ_HAVE_MEMALIGN)
+ free( ptr );
+#elif defined(OPJ_HAVE__ALIGNED_MALLOC)
_aligned_free( ptr );
#else
- free( ptr );
+ /* Generic implementation has malloced pointer stored in front of used area */
+ if (ptr != NULL) {
+ free(((void**) ptr)[-1]);
+ }
#endif
}