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authorLei Zhang <thestig@chromium.org>2016-01-15 19:38:03 -0800
committerLei Zhang <thestig@chromium.org>2016-01-15 19:38:03 -0800
commita76a6d8bcb76077fa248b64c5d64791dc8f23771 (patch)
tree1ea7c74990f4ca926ca61f29fc63831e23303521 /third_party/libpng16/pngmem.c
parent2991d8d171e917912fd250c3c8ed693568dc1d8c (diff)
downloadpdfium-a76a6d8bcb76077fa248b64c5d64791dc8f23771.tar.xz
XFA: Rename libpng to libpng16.chromium/2625chromium/2624
Otherwise this conflicts with Chromium's copy if the include paths just happens to be in the wrong order. Since the two copies of libpng are of different versions, we cannot use Chromium's copy. TBR=tsepez@chromium.org,ochang@chromium.org Review URL: https://codereview.chromium.org/1599513004 .
Diffstat (limited to 'third_party/libpng16/pngmem.c')
-rw-r--r--third_party/libpng16/pngmem.c287
1 files changed, 287 insertions, 0 deletions
diff --git a/third_party/libpng16/pngmem.c b/third_party/libpng16/pngmem.c
new file mode 100644
index 0000000000..db71219520
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+++ b/third_party/libpng16/pngmem.c
@@ -0,0 +1,287 @@
+
+/* pngmem.c - stub functions for memory allocation
+ *
+ * Last changed in libpng 1.6.15 [November 20, 2014]
+ * Copyright (c) 1998-2014 Glenn Randers-Pehrson
+ * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
+ * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
+ *
+ * This code is released under the libpng license.
+ * For conditions of distribution and use, see the disclaimer
+ * and license in png.h
+ *
+ * This file provides a location for all memory allocation. Users who
+ * need special memory handling are expected to supply replacement
+ * functions for png_malloc() and png_free(), and to use
+ * png_create_read_struct_2() and png_create_write_struct_2() to
+ * identify the replacement functions.
+ */
+
+#include "pngpriv.h"
+
+void* FXMEM_DefaultAlloc(int byte_size, int);
+void FXMEM_DefaultFree(void* pointer, int);
+
+#if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED)
+/* Free a png_struct */
+void /* PRIVATE */
+png_destroy_png_struct(png_structrp png_ptr)
+{
+ if (png_ptr != NULL)
+ {
+ /* png_free might call png_error and may certainly call
+ * png_get_mem_ptr, so fake a temporary png_struct to support this.
+ */
+ png_struct dummy_struct = *png_ptr;
+ memset(png_ptr, 0, (sizeof *png_ptr));
+ png_free(&dummy_struct, png_ptr);
+
+# ifdef PNG_SETJMP_SUPPORTED
+ /* We may have a jmp_buf left to deallocate. */
+ png_free_jmpbuf(&dummy_struct);
+# endif
+ }
+}
+
+/* Allocate memory. For reasonable files, size should never exceed
+ * 64K. However, zlib may allocate more than 64K if you don't tell
+ * it not to. See zconf.h and png.h for more information. zlib does
+ * need to allocate exactly 64K, so whatever you call here must
+ * have the ability to do that.
+ */
+PNG_FUNCTION(png_voidp,PNGAPI
+png_calloc,(png_const_structrp png_ptr, png_alloc_size_t size),PNG_ALLOCATED)
+{
+ png_voidp ret;
+
+ ret = png_malloc(png_ptr, size);
+
+ if (ret != NULL)
+ memset(ret, 0, size);
+
+ return ret;
+}
+
+/* png_malloc_base, an internal function added at libpng 1.6.0, does the work of
+ * allocating memory, taking into account limits and PNG_USER_MEM_SUPPORTED.
+ * Checking and error handling must happen outside this routine; it returns NULL
+ * if the allocation cannot be done (for any reason.)
+ */
+PNG_FUNCTION(png_voidp /* PRIVATE */,
+png_malloc_base,(png_const_structrp png_ptr, png_alloc_size_t size),
+ PNG_ALLOCATED)
+{
+ /* Moved to png_malloc_base from png_malloc_default in 1.6.0; the DOS
+ * allocators have also been removed in 1.6.0, so any 16-bit system now has
+ * to implement a user memory handler. This checks to be sure it isn't
+ * called with big numbers.
+ */
+#ifndef PNG_USER_MEM_SUPPORTED
+ PNG_UNUSED(png_ptr)
+#endif
+
+ /* Some compilers complain that this is always true. However, it
+ * can be false when integer overflow happens.
+ */
+ if (size > 0 && size <= PNG_SIZE_MAX
+# ifdef PNG_MAX_MALLOC_64K
+ && size <= 65536U
+# endif
+ )
+ {
+#ifdef PNG_USER_MEM_SUPPORTED
+ if (png_ptr != NULL && png_ptr->malloc_fn != NULL)
+ return png_ptr->malloc_fn(png_constcast(png_structrp,png_ptr), size);
+
+ else
+#endif
+ return FXMEM_DefaultAlloc((int)size, 0);
+ }
+
+ else
+ return NULL;
+}
+
+#if defined(PNG_TEXT_SUPPORTED) || defined(PNG_sPLT_SUPPORTED) ||\
+ defined(PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED)
+/* This is really here only to work round a spurious warning in GCC 4.6 and 4.7
+ * that arises because of the checks in png_realloc_array that are repeated in
+ * png_malloc_array.
+ */
+static png_voidp
+png_malloc_array_checked(png_const_structrp png_ptr, int nelements,
+ size_t element_size)
+{
+ png_alloc_size_t req = nelements; /* known to be > 0 */
+
+ if (req <= PNG_SIZE_MAX/element_size)
+ return png_malloc_base(png_ptr, req * element_size);
+
+ /* The failure case when the request is too large */
+ return NULL;
+}
+
+PNG_FUNCTION(png_voidp /* PRIVATE */,
+png_malloc_array,(png_const_structrp png_ptr, int nelements,
+ size_t element_size),PNG_ALLOCATED)
+{
+ if (nelements <= 0 || element_size == 0)
+ png_error(png_ptr, "internal error: array alloc");
+
+ return png_malloc_array_checked(png_ptr, nelements, element_size);
+}
+
+PNG_FUNCTION(png_voidp /* PRIVATE */,
+png_realloc_array,(png_const_structrp png_ptr, png_const_voidp old_array,
+ int old_elements, int add_elements, size_t element_size),PNG_ALLOCATED)
+{
+ /* These are internal errors: */
+ if (add_elements <= 0 || element_size == 0 || old_elements < 0 ||
+ (old_array == NULL && old_elements > 0))
+ png_error(png_ptr, "internal error: array realloc");
+
+ /* Check for overflow on the elements count (so the caller does not have to
+ * check.)
+ */
+ if (add_elements <= INT_MAX - old_elements)
+ {
+ png_voidp new_array = png_malloc_array_checked(png_ptr,
+ old_elements+add_elements, element_size);
+
+ if (new_array != NULL)
+ {
+ /* Because png_malloc_array worked the size calculations below cannot
+ * overflow.
+ */
+ if (old_elements > 0)
+ memcpy(new_array, old_array, element_size*(unsigned)old_elements);
+
+ memset((char*)new_array + element_size*(unsigned)old_elements, 0,
+ element_size*(unsigned)add_elements);
+
+ return new_array;
+ }
+ }
+
+ return NULL; /* error */
+}
+#endif /* TEXT || sPLT || STORE_UNKNOWN_CHUNKS */
+
+/* Various functions that have different error handling are derived from this.
+ * png_malloc always exists, but if PNG_USER_MEM_SUPPORTED is defined a separate
+ * function png_malloc_default is also provided.
+ */
+PNG_FUNCTION(png_voidp,PNGAPI
+png_malloc,(png_const_structrp png_ptr, png_alloc_size_t size),PNG_ALLOCATED)
+{
+ png_voidp ret;
+
+ if (png_ptr == NULL)
+ return NULL;
+
+ ret = png_malloc_base(png_ptr, size);
+
+ if (ret == NULL)
+ png_error(png_ptr, "Out of memory"); /* 'm' means png_malloc */
+
+ return ret;
+}
+
+#ifdef PNG_USER_MEM_SUPPORTED
+PNG_FUNCTION(png_voidp,PNGAPI
+png_malloc_default,(png_const_structrp png_ptr, png_alloc_size_t size),
+ PNG_ALLOCATED PNG_DEPRECATED)
+{
+ png_voidp ret;
+
+ if (png_ptr == NULL)
+ return NULL;
+
+ /* Passing 'NULL' here bypasses the application provided memory handler. */
+ ret = png_malloc_base(NULL/*use malloc*/, size);
+
+ if (ret == NULL)
+ png_error(png_ptr, "Out of Memory"); /* 'M' means png_malloc_default */
+
+ return ret;
+}
+#endif /* USER_MEM */
+
+/* This function was added at libpng version 1.2.3. The png_malloc_warn()
+ * function will issue a png_warning and return NULL instead of issuing a
+ * png_error, if it fails to allocate the requested memory.
+ */
+PNG_FUNCTION(png_voidp,PNGAPI
+png_malloc_warn,(png_const_structrp png_ptr, png_alloc_size_t size),
+ PNG_ALLOCATED)
+{
+ if (png_ptr != NULL)
+ {
+ png_voidp ret = png_malloc_base(png_ptr, size);
+
+ if (ret != NULL)
+ return ret;
+
+ png_warning(png_ptr, "Out of memory");
+ }
+
+ return NULL;
+}
+
+/* Free a pointer allocated by png_malloc(). If ptr is NULL, return
+ * without taking any action.
+ */
+void PNGAPI
+png_free(png_const_structrp png_ptr, png_voidp ptr)
+{
+ if (png_ptr == NULL || ptr == NULL)
+ return;
+
+#ifdef PNG_USER_MEM_SUPPORTED
+ if (png_ptr->free_fn != NULL)
+ png_ptr->free_fn(png_constcast(png_structrp,png_ptr), ptr);
+
+ else
+ png_free_default(png_ptr, ptr);
+}
+
+PNG_FUNCTION(void,PNGAPI
+png_free_default,(png_const_structrp png_ptr, png_voidp ptr),PNG_DEPRECATED)
+{
+ if (png_ptr == NULL || ptr == NULL)
+ return;
+#endif /* USER_MEM */
+
+ FXMEM_DefaultFree(ptr, 0);
+}
+
+#ifdef PNG_USER_MEM_SUPPORTED
+/* This function is called when the application wants to use another method
+ * of allocating and freeing memory.
+ */
+void PNGAPI
+png_set_mem_fn(png_structrp png_ptr, png_voidp mem_ptr, png_malloc_ptr
+ malloc_fn, png_free_ptr free_fn)
+{
+ if (png_ptr != NULL)
+ {
+ png_ptr->mem_ptr = mem_ptr;
+ png_ptr->malloc_fn = malloc_fn;
+ png_ptr->free_fn = free_fn;
+ }
+}
+
+/* This function returns a pointer to the mem_ptr associated with the user
+ * functions. The application should free any memory associated with this
+ * pointer before png_write_destroy and png_read_destroy are called.
+ */
+png_voidp PNGAPI
+png_get_mem_ptr(png_const_structrp png_ptr)
+{
+ if (png_ptr == NULL)
+ return NULL;
+
+ return png_ptr->mem_ptr;
+}
+#endif /* USER_MEM */
+#endif /* READ || WRITE */