diff options
Diffstat (limited to 'src/loadpng.c')
| -rw-r--r-- | src/loadpng.c | 131 |
1 files changed, 64 insertions, 67 deletions
diff --git a/src/loadpng.c b/src/loadpng.c index fce5066..ed12886 100644 --- a/src/loadpng.c +++ b/src/loadpng.c @@ -10,95 +10,92 @@ #include <assert.h> #include <png.h> -static_assert(sizeof(png_byte) == sizeof( ((ql_raster_image_t *)0)->data[0]), "Code relies on png_byte being compatible with ql_raster_image_t data "); +static_assert(sizeof(png_byte) == sizeof(((ql_raster_image_t *) 0)->data[0]), + "Code relies on png_byte being compatible with ql_raster_image_t data "); ql_raster_image_t *loadpng(const char *path) { - ql_raster_image_t *ret = NULL; + ql_raster_image_t *ret = NULL; - if (!path) - goto out; + if (!path) + goto out; - FILE *f = fopen(path, "rb"); - if (!f) - goto out; + FILE *f = fopen(path, "rb"); + if (!f) + goto out; - uint8_t header[8]; - if (fread(header, 1, sizeof(header), f) != 8) - goto close_out; + uint8_t header[8]; + if (fread(header, 1, sizeof(header), f) != 8) + goto close_out; - if (!png_check_sig(header, sizeof(header))) - goto close_out; + if (!png_check_sig(header, sizeof(header))) + goto close_out; - png_infop info_ptr = NULL, end_ptr = NULL; - png_structp png_ptr = - png_create_read_struct (PNG_LIBPNG_VER_STRING, NULL, NULL, NULL); - if (!png_ptr) - goto close_out; + png_infop info_ptr = NULL, end_ptr = NULL; + png_structp png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL); + if (!png_ptr) + goto close_out; - info_ptr = png_create_info_struct(png_ptr); - if (!info_ptr) - goto destroy_read_out; + info_ptr = png_create_info_struct(png_ptr); + if (!info_ptr) + goto destroy_read_out; - end_ptr = png_create_info_struct(png_ptr); - if (!end_ptr) - goto destroy_read_out; + end_ptr = png_create_info_struct(png_ptr); + if (!end_ptr) + goto destroy_read_out; - if (setjmp(png_jmpbuf(png_ptr))) - goto destroy_read_out; + if (setjmp(png_jmpbuf(png_ptr))) + goto destroy_read_out; - png_init_io(png_ptr, f); - png_set_sig_bytes(png_ptr, sizeof(header)); + png_init_io(png_ptr, f); + png_set_sig_bytes(png_ptr, sizeof(header)); - png_read_info(png_ptr, info_ptr); + png_read_info(png_ptr, info_ptr); - png_uint_32 width, height; - int bit_depth, color_type; - png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, - &color_type, NULL, NULL, NULL); + png_uint_32 width, height; + int bit_depth, color_type; + png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, &color_type, NULL, NULL, NULL); - if (color_type & PNG_COLOR_MASK_ALPHA) - png_set_strip_alpha(png_ptr); - if (color_type & (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)) - png_set_rgb_to_gray_fixed(png_ptr, 1, -1, -1); // force into grayscale - if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8) - png_set_expand_gray_1_2_4_to_8(png_ptr); // get us a known output format + if (color_type & PNG_COLOR_MASK_ALPHA) + png_set_strip_alpha(png_ptr); + if (color_type & (PNG_COLOR_MASK_COLOR | PNG_COLOR_MASK_PALETTE)) + png_set_rgb_to_gray_fixed(png_ptr, 1, -1, -1); // force into grayscale + if (color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8) + png_set_expand_gray_1_2_4_to_8(png_ptr); // get us a known output format - png_read_update_info(png_ptr, info_ptr); + png_read_update_info(png_ptr, info_ptr); - png_bytepp row_ptrs = calloc(height, sizeof(png_bytep)); - if (!row_ptrs) - goto destroy_read_out; + png_bytepp row_ptrs = calloc(height, sizeof(png_bytep)); + if (!row_ptrs) + goto destroy_read_out; - const unsigned row_bytes = width * sizeof(png_byte); - ql_raster_image_t *img = - calloc(1, sizeof(ql_raster_image_t) + height * row_bytes); - if (!img) - goto free_image_out; + const unsigned row_bytes = width * sizeof(png_byte); + ql_raster_image_t *img = calloc(1, sizeof(ql_raster_image_t) + height * row_bytes); + if (!img) + goto free_image_out; - if (setjmp(png_jmpbuf(png_ptr))) - goto free_image_out; + if (setjmp(png_jmpbuf(png_ptr))) + goto free_image_out; - for (png_uint_32 i = 0; i < height; ++i) - row_ptrs[i] = (png_bytep)(img->data + (i * row_bytes)); + for (png_uint_32 i = 0; i < height; ++i) + row_ptrs[i] = (png_bytep) (img->data + (i * row_bytes)); - png_read_image(png_ptr, row_ptrs); - png_read_end(png_ptr, end_ptr); + png_read_image(png_ptr, row_ptrs); + png_read_end(png_ptr, end_ptr); - img->height = height; - img->width = width; + img->height = height; + img->width = width; - ret = img; - img = NULL; // don't free it, we're returning it now + ret = img; + img = NULL; // don't free it, we're returning it now -free_image_out: - free(img); - free(row_ptrs); -destroy_read_out: - png_destroy_read_struct( - &png_ptr, info_ptr ? &info_ptr : NULL, end_ptr ? &end_ptr : NULL); -close_out: - fclose(f); -out: - return ret; + free_image_out: + free(img); + free(row_ptrs); + destroy_read_out: + png_destroy_read_struct(&png_ptr, info_ptr ? &info_ptr : NULL, end_ptr ? &end_ptr : NULL); + close_out: + fclose(f); + out: + return ret; } |