// Copyright 2012 Google Inc. All Rights Reserved. // // Use of this source code is governed by a BSD-style license // that can be found in the COPYING file in the root of the source // tree. An additional intellectual property rights grant can be found // in the file PATENTS. All contributing project authors may // be found in the AUTHORS file in the root of the source tree. // ----------------------------------------------------------------------------- // // Misc. common utility functions // // Author: Skal (pascal.massimino@gmail.com) #include #include // for memcpy() #include "webp/decode.h" #include "webp/encode.h" #include "webp/format_constants.h" // for MAX_PALETTE_SIZE #include "./utils.h" // If PRINT_MEM_INFO is defined, extra info (like total memory used, number of // alloc/free etc) is printed. For debugging/tuning purpose only (it's slow, // and not multi-thread safe!). // An interesting alternative is valgrind's 'massif' tool: // http://valgrind.org/docs/manual/ms-manual.html // Here is an example command line: /* valgrind --tool=massif --massif-out-file=massif.out \ --stacks=yes --alloc-fn=WebPSafeAlloc --alloc-fn=WebPSafeCalloc ms_print massif.out */ // In addition: // * if PRINT_MEM_TRAFFIC is defined, all the details of the malloc/free cycles // are printed. // * if MALLOC_FAIL_AT is defined, the global environment variable // $MALLOC_FAIL_AT is used to simulate a memory error when calloc or malloc // is called for the nth time. Example usage: // export MALLOC_FAIL_AT=50 && ./examples/cwebp input.png // * if MALLOC_LIMIT is defined, the global environment variable $MALLOC_LIMIT // sets the maximum amount of memory (in bytes) made available to libwebp. // This can be used to emulate environment with very limited memory. // Example: export MALLOC_LIMIT=64000000 && ./examples/dwebp picture.webp // #define PRINT_MEM_INFO // #define PRINT_MEM_TRAFFIC // #define MALLOC_FAIL_AT // #define MALLOC_LIMIT //------------------------------------------------------------------------------ // Checked memory allocation #if defined(PRINT_MEM_INFO) #include static int num_malloc_calls = 0; static int num_calloc_calls = 0; static int num_free_calls = 0; static int countdown_to_fail = 0; // 0 = off typedef struct MemBlock MemBlock; struct MemBlock { void* ptr_; size_t size_; MemBlock* next_; }; static MemBlock* all_blocks = NULL; static size_t total_mem = 0; static size_t total_mem_allocated = 0; static size_t high_water_mark = 0; static size_t mem_limit = 0; static int exit_registered = 0; static void PrintMemInfo(void) { fprintf(stderr, "\nMEMORY INFO:\n"); fprintf(stderr, "num calls to: malloc = %4d\n", num_malloc_calls); fprintf(stderr, " calloc = %4d\n", num_calloc_calls); fprintf(stderr, " free = %4d\n", num_free_calls); fprintf(stderr, "total_mem: %u\n", (uint32_t)total_mem); fprintf(stderr, "total_mem allocated: %u\n", (uint32_t)total_mem_allocated); fprintf(stderr, "high-water mark: %u\n", (uint32_t)high_water_mark); while (all_blocks != NULL) { MemBlock* b = all_blocks; all_blocks = b->next_; free(b); } } static void Increment(int* const v) { if (!exit_registered) { #if defined(MALLOC_FAIL_AT) { const char* const malloc_fail_at_str = getenv("MALLOC_FAIL_AT"); if (malloc_fail_at_str != NULL) { countdown_to_fail = atoi(malloc_fail_at_str); } } #endif #if defined(MALLOC_LIMIT) { const char* const malloc_limit_str = getenv("MALLOC_LIMIT"); if (malloc_limit_str != NULL) { mem_limit = atoi(malloc_limit_str); } } #endif (void)countdown_to_fail; (void)mem_limit; atexit(PrintMemInfo); exit_registered = 1; } ++*v; } static void AddMem(void* ptr, size_t size) { if (ptr != NULL) { MemBlock* const b = (MemBlock*)malloc(sizeof(*b)); if (b == NULL) abort(); b->next_ = all_blocks; all_blocks = b; b->ptr_ = ptr; b->size_ = size; total_mem += size; total_mem_allocated += size; #if defined(PRINT_MEM_TRAFFIC) #if defined(MALLOC_FAIL_AT) fprintf(stderr, "fail-count: %5d [mem=%u]\n", num_malloc_calls + num_calloc_calls, (uint32_t)total_mem); #else fprintf(stderr, "Mem: %u (+%u)\n", (uint32_t)total_mem, (uint32_t)size); #endif #endif if (total_mem > high_water_mark) high_water_mark = total_mem; } } static void SubMem(void* ptr) { if (ptr != NULL) { MemBlock** b = &all_blocks; // Inefficient search, but that's just for debugging. while (*b != NULL && (*b)->ptr_ != ptr) b = &(*b)->next_; if (*b == NULL) { fprintf(stderr, "Invalid pointer free! (%p)\n", ptr); abort(); } { MemBlock* const block = *b; *b = block->next_; total_mem -= block->size_; #if defined(PRINT_MEM_TRAFFIC) fprintf(stderr, "Mem: %u (-%u)\n", (uint32_t)total_mem, (uint32_t)block->size_); #endif free(block); } } } #else #define Increment(v) do {} while (0) #define AddMem(p, s) do {} while (0) #define SubMem(p) do {} while (0) #endif // Returns 0 in case of overflow of nmemb * size. static int CheckSizeArgumentsOverflow(uint64_t nmemb, size_t size) { const uint64_t total_size = nmemb * size; if (nmemb == 0) return 1; if ((uint64_t)size > WEBP_MAX_ALLOCABLE_MEMORY / nmemb) return 0; if (total_size != (size_t)total_size) return 0; #if defined(PRINT_MEM_INFO) && defined(MALLOC_FAIL_AT) if (countdown_to_fail > 0 && --countdown_to_fail == 0) { return 0; // fake fail! } #endif #if defined(MALLOC_LIMIT) if (mem_limit > 0 && total_mem + total_size >= mem_limit) { return 0; // fake fail! } #endif return 1; } void* WebPSafeMalloc(uint64_t nmemb, size_t size) { void* ptr; Increment(&num_malloc_calls); if (!CheckSizeArgumentsOverflow(nmemb, size)) return NULL; assert(nmemb * size > 0); ptr = malloc((size_t)(nmemb * size)); AddMem(ptr, (size_t)(nmemb * size)); return ptr; } void* WebPSafeCalloc(uint64_t nmemb, size_t size) { void* ptr; Increment(&num_calloc_calls); if (!CheckSizeArgumentsOverflow(nmemb, size)) return NULL; assert(nmemb * size > 0); ptr = calloc((size_t)nmemb, size); AddMem(ptr, (size_t)(nmemb * size)); return ptr; } void WebPSafeFree(void* const ptr) { if (ptr != NULL) { Increment(&num_free_calls); SubMem(ptr); } free(ptr); } // Public API function. void WebPFree(void* ptr) { free(ptr); } //------------------------------------------------------------------------------ void WebPCopyPlane(const uint8_t* src, int src_stride, uint8_t* dst, int dst_stride, int width, int height) { assert(src != NULL && dst != NULL); assert(src_stride >= width && dst_stride >= width); while (height-- > 0) { memcpy(dst, src, width); src += src_stride; dst += dst_stride; } } void WebPCopyPixels(const WebPPicture* const src, WebPPicture* const dst) { assert(src != NULL && dst != NULL); assert(src->width == dst->width && src->height == dst->height); assert(src->use_argb && dst->use_argb); WebPCopyPlane((uint8_t*)src->argb, 4 * src->argb_stride, (uint8_t*)dst->argb, 4 * dst->argb_stride, 4 * src->width, src->height); } //------------------------------------------------------------------------------ #define MAX_COLOR_COUNT MAX_PALETTE_SIZE #define COLOR_HASH_SIZE (MAX_COLOR_COUNT * 4) #define COLOR_HASH_RIGHT_SHIFT 22 // 32 - log2(COLOR_HASH_SIZE). int WebPGetColorPalette(const WebPPicture* const pic, uint32_t* const palette) { int i; int x, y; int num_colors = 0; uint8_t in_use[COLOR_HASH_SIZE] = { 0 }; uint32_t colors[COLOR_HASH_SIZE]; static const uint32_t kHashMul = 0x1e35a7bdU; const uint32_t* argb = pic->argb; const int width = pic->width; const int height = pic->height; uint32_t last_pix = ~argb[0]; // so we're sure that last_pix != argb[0] assert(pic != NULL); assert(pic->use_argb); for (y = 0; y < height; ++y) { for (x = 0; x < width; ++x) { int key; if (argb[x] == last_pix) { continue; } last_pix = argb[x]; key = (kHashMul * last_pix) >> COLOR_HASH_RIGHT_SHIFT; while (1) { if (!in_use[key]) { colors[key] = last_pix; in_use[key] = 1; ++num_colors; if (num_colors > MAX_COLOR_COUNT) { return MAX_COLOR_COUNT + 1; // Exact count not needed. } break; } else if (colors[key] == last_pix) { break; // The color is already there. } else { // Some other color sits here, so do linear conflict resolution. ++key; key &= (COLOR_HASH_SIZE - 1); // Key mask. } } } argb += pic->argb_stride; } if (palette != NULL) { // Fill the colors into palette. num_colors = 0; for (i = 0; i < COLOR_HASH_SIZE; ++i) { if (in_use[i]) { palette[num_colors] = colors[i]; ++num_colors; } } } return num_colors; } #undef MAX_COLOR_COUNT #undef COLOR_HASH_SIZE #undef COLOR_HASH_RIGHT_SHIFT //------------------------------------------------------------------------------