minor tweaks to the code

[openjpeg.git] / src / lib / openjp2 / opj_malloc.c

diff --git a/src/lib/openjp2/opj_malloc.c b/src/lib/openjp2/opj_malloc.c
index a170d8527c475244a044a5b706b83ee677aec947..30d892587eb23e076c2d6d19d310c10abaa1d7da 100644 (file)
--- a/src/lib/openjp2/opj_malloc.c
+++ b/src/lib/openjp2/opj_malloc.c
@@ -30,43 +30,71 @@
  */
 #define OPJ_SKIP_POISON
 #include "opj_malloc.h"
+#include "opj_config_private.h"
 #include <stdlib.h>
+#include <string.h>
+#include <inttypes.h>
+#include <assert.h>
 
-static inline void *opj_aligned_alloc(size_t alignment, size_t size)
+static inline void *opj_aligned_alloc_n(size_t alignment, size_t size)
 {
-#ifndef HAVE_ALIGNED_ALLOC
-  /* older linux */
-#ifdef HAVE_MEMALIGN
-  assert( size % alignment == 0 );
-  return memalign( alignment, size );
-#endif /* HAVE_MEMALIGN */
-
-/* _MSC_VER */
-#ifdef HAVE__ALIGNED_MALLOC
-  return _aligned_malloc( alignment, size );
-#endif /* HAVE__ALIGNED_MALLOC */
-
-/* MacOSX / clang */
-#if defined(HAVE_POSIX_MEMALIGN) && !defined(HAVE_MEMALIGN)
+#if defined(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+   * superseded by aligned_alloc, it is more portable to older POSIX systems
+   * that do not support ISO C11.  */
   void* ptr;
   if (posix_memalign (&ptr, alignment, size))
   {
     ptr = NULL;
   }
   return ptr;
-#endif /* HAVE_POSIX_MEMALIGN */
-
-#else /* HAVE_ALIGNED_ALLOC */
-  return aligned_alloc( alignment, size );
-#endif /* HAVE_ALIGNED_ALLOC */
+  /* older linux */
+#elif defined(HAVE_MEMALIGN)
+  assert( size & (alignment - 1u) == 0 );
+  return memalign( alignment, size );
+/* _MSC_VER */
+#elif defined(HAVE__ALIGNED_MALLOC)
+  return _aligned_malloc( alignment, size );
+#else
 /* TODO: _mm_malloc(x,y) */
+#error missing aligned alloc function
+#endif
+}
+static inline void *opj_aligned_realloc_n(void *ptr, size_t alignment, size_t size)
+{
+  void *a_ptr;
+/* no portable aligned realloc */
+#if defined(HAVE_POSIX_MEMALIGN) || defined(HAVE_MEMALIGN)
+  /* glibc doc states one can mixed aligned malloc with realloc */
+  void *r_ptr = realloc( ptr, size );
+  assert( alignment > 0 );
+  /* fast path */
+  /* we simply use `size_t` to cast, since we are only interest in binary AND
+   * operator */
+  if( ((size_t)r_ptr & (alignment - 1u)) == 0 )
+    return r_ptr;
+  /* this is non-trivial to implement a portable aligned realloc, so use a
+   * simple approach where we do not need a function that return the size of an
+   * allocated array (eg. _msize on Windows, malloc_size on MacOS,
+   * malloc_usable_size on systems with glibc) */
+  a_ptr = opj_aligned_alloc_n(alignment, size);
+  /* memory may overlap, do not use memcpy */
+  memmove(a_ptr, r_ptr, size);
+  free( r_ptr );
+  return a_ptr;
+/* _MSC_VER */
+#elif defined(HAVE__ALIGNED_MALLOC)
+  return _aligned_realloc( ptr, size, alignment );
+#else
+/* TODO: _mm_malloc(x,y) */
+#error missing aligned realloc function
+#endif
 }
-
 void * opj_malloc(size_t size)
 {
   return malloc(size);
 }
-
 void * opj_calloc(size_t numOfElements, size_t sizeOfElements)
 {
   return calloc(numOfElements, sizeOfElements);
@@ -74,7 +102,11 @@ void * opj_calloc(size_t numOfElements, size_t sizeOfElements)
 
 void *opj_aligned_malloc(size_t size)
 {
-  return opj_aligned_alloc(size,16);
+  return opj_aligned_alloc_n(16u,size);
+}
+void * opj_aligned_realloc(void *ptr, size_t size)
+{
+  return opj_aligned_realloc_n(ptr,16u,size);
 }
 
 void opj_aligned_free(void* ptr)