void *iw_realloc(const char *file, unsigned int line, void *ptr, size_t size) {
if(!iw_memory_tracking) {
return realloc(ptr, size);
}
void *new_chunk = NULL;
// TODO: To simplify realloc we just allocate a new memory chunk and free the
// old one.
if(size != 0) {
new_chunk = iw_malloc(file, line, size);
if(new_chunk == NULL) {
// Realloc does not free or move the old memory if allocation fails.
return NULL;
}
}
if(ptr != NULL) {
if(new_chunk != NULL) {
void *len_ptr = ptr - PRE_GUARD_SIZE - LEN_SIZE;
unsigned int len = ntohl(*(unsigned int *)len_ptr);
memcpy(new_chunk, ptr, len);
}
iw_free(ptr);
}
return new_chunk;
}
// Allocate a large block of memory, presumably for image data.
// Use this if integer overflow is a possibility when multiplying
// two factors together.
void *iw_malloc_large(struct iw_context *ctx, size_t n1, size_t n2)
{
if(n1 > ctx->max_malloc/n2) {
iw_seterror(ctx,iwcore_get_string(ctx,iws_image_too_large));
return NULL;
}
return iw_malloc(ctx,n1*n2);
}
char *iw_strdup(const char *file, unsigned int line, const char *ptr) {
if(!iw_memory_tracking) {
return strdup(ptr);
}
int len = strlen(ptr) + 1;
void *chunk = iw_malloc(file, line, len);
if(chunk == NULL) {
return NULL;
}
memcpy(chunk, ptr, len + 1);
return chunk;
}
void *iw_calloc(const char *file, unsigned int line, int elems, size_t size) {
if(!iw_memory_tracking) {
return calloc(elems, size);
}
void *chunk = iw_malloc(file, line, elems * size);
if(chunk == NULL) {
return NULL;
}
memset(chunk, 0, size);
return chunk;
}
int iw_file_to_memory(struct iw_context *ctx, struct iw_iodescr *iodescr,
void **pmem, size_t *psize)
{
int ret;
size_t bytesread;
*pmem=NULL;
*psize=0;
if(!iodescr->getfilesize_fn) return 0;
ret = (*iodescr->getfilesize_fn)(ctx,iodescr,psize);
if(!ret) return 0;
*pmem = iw_malloc(ctx,*psize);
ret = (*iodescr->read_fn)(ctx,iodescr,*pmem,*psize,&bytesread);
if(!ret) return 0;
if(bytesread != *psize) return 0;
return 1;
}
// Optimize to palette, or 1-, 2-, or 4-bpp grayscale.
static void iwopt_try_pal_lowgray_optimization(struct iw_context *ctx, struct iw_opt_ctx *optctx)
{
int ret;
int binary_trns;
unsigned int trns_shade;
if(!(ctx->output_profile&IW_PROFILE_PAL1) &&
!(ctx->output_profile&IW_PROFILE_PAL2) &&
!(ctx->output_profile&IW_PROFILE_PAL4) &&
!(ctx->output_profile&IW_PROFILE_PAL8) &&
!(ctx->output_profile&IW_PROFILE_GRAY1) &&
!(ctx->output_profile&IW_PROFILE_GRAY2) &&
!(ctx->output_profile&IW_PROFILE_GRAY4) )
{
// Output format doesn't support anything that this optimization can provide.
return;
}
if(optctx->bit_depth!=8) {
// Palettes aren't supported with bitdepth>8.
return;
}
optctx->palette = iw_malloc(ctx,sizeof(struct iw_palette));
if(!optctx->palette) return;
optctx->palette->num_entries=0;
ret = optctx_collect_palette_colors(ctx,optctx);
if(!ret) {
// Image can't be converted to a palette image.
goto done;
}
// optctx->palette now contains a palette that can be used.
// For images that have at most 256 (8-bit-compatible) colors, the order
// of preference is gray1, pal1, gray2, pal2, gray4, pal4, gray8, pal8.
if(ctx->opt_grayscale && (ctx->output_profile&IW_PROFILE_GRAY1) && iwopt_palette_is_valid_gray(ctx,optctx,1,&binary_trns,&trns_shade)) {
// Replace the palette with a fully-populated grayscale palette.
// The palette might already be correct, but it might not be.
// It will be missing any gray shade that wasn't in the image.
iwopt_make_gray_palette(ctx,optctx,1);
if(binary_trns) {
optctx->has_colorkey_trns = 1;
optctx->colorkey_r = optctx->colorkey_b = optctx->colorkey_g = trns_shade;
}
}
else if(iwopt_palette_opt_ok(ctx,optctx,1)) {
;
}
else if(ctx->opt_grayscale && (ctx->output_profile&IW_PROFILE_GRAY2) && iwopt_palette_is_valid_gray(ctx,optctx,2,&binary_trns,&trns_shade)) {
iwopt_make_gray_palette(ctx,optctx,2);
if(binary_trns) {
optctx->has_colorkey_trns = 1;
optctx->colorkey_r = optctx->colorkey_b = optctx->colorkey_g = trns_shade;
}
}
else if(iwopt_palette_opt_ok(ctx,optctx,2)) {
;
}
else if(ctx->opt_grayscale && (ctx->output_profile&IW_PROFILE_GRAY4) && iwopt_palette_is_valid_gray(ctx,optctx,4,&binary_trns,&trns_shade)) {
iwopt_make_gray_palette(ctx,optctx,4);
if(binary_trns) {
optctx->has_colorkey_trns = 1;
optctx->colorkey_r = optctx->colorkey_b = optctx->colorkey_g = trns_shade;
}
}
else if(iwopt_palette_opt_ok(ctx,optctx,4)) {
;
}
else if(ctx->opt_grayscale && (ctx->output_profile&IW_PROFILE_GRAYSCALE) && iwopt_palette_is_valid_gray(ctx,optctx,8,&binary_trns,&trns_shade)) {
// This image can best be encoded as 8-bit grayscale. We don't handle that here.
goto done;
}
else if(iwopt_palette_opt_ok(ctx,optctx,8)) {
;
}
else {
// Found no optimizations that we can perform.
goto done;
}
if(!optctx->palette_is_grayscale) {
// Sort the palette
qsort((void*)optctx->palette->entry,optctx->palette->num_entries,
sizeof(struct iw_rgba8color),iwopt_palsortfunc);
}
iwopt_convert_to_palette_image(ctx,optctx);
done:
if(optctx->imgtype!=IW_IMGTYPE_PALETTE) {
iw_free(optctx->palette);
optctx->palette = NULL;
}
}