weston/shared/image-loader.c
Quentin Glidic 9ba1546172
shared/image: Silence maybe-uninitialized warning
shared/image-loader.c: In function 'load_image':
shared/image-loader.c:434:12: warning: 'image' may be used uninitialized
in this function [-Wmaybe-uninitialized]
  } else if (!image) {
              ^

Warning produced by GCC 5.3 and 6.1, with -Og.

Signed-off-by: Quentin Glidic <sardemff7+git@sardemff7.net>
Reviewed-by: Giulio Camuffo <giuliocamuffo@gmail.com>
2016-08-15 16:31:00 +02:00

441 lines
9.7 KiB
C

/*
* Copyright © 2008-2012 Kristian Høgsberg
* Copyright © 2012 Intel Corporation
*
* Permission is hereby granted, free of charge, to any person obtaining
* a copy of this software and associated documentation files (the
* "Software"), to deal in the Software without restriction, including
* without limitation the rights to use, copy, modify, merge, publish,
* distribute, sublicense, and/or sell copies of the Software, and to
* permit persons to whom the Software is furnished to do so, subject to
* the following conditions:
*
* The above copyright notice and this permission notice (including the
* next paragraph) shall be included in all copies or substantial
* portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include "config.h"
#include <errno.h>
#include <stdlib.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>
#include <png.h>
#include <pixman.h>
#include "shared/helpers.h"
#include "image-loader.h"
#ifdef HAVE_JPEG
#include <jpeglib.h>
#endif
#ifdef HAVE_WEBP
#include <webp/decode.h>
#endif
static int
stride_for_width(int width)
{
return width * 4;
}
static void
pixman_image_destroy_func(pixman_image_t *image, void *data)
{
free(data);
}
#ifdef HAVE_JPEG
static void
swizzle_row(JSAMPLE *row, JDIMENSION width)
{
JSAMPLE *s;
uint32_t *d;
s = row + (width - 1) * 3;
d = (uint32_t *) (row + (width - 1) * 4);
while (s >= row) {
*d = 0xff000000 | (s[0] << 16) | (s[1] << 8) | (s[2] << 0);
s -= 3;
d--;
}
}
static void
error_exit(j_common_ptr cinfo)
{
longjmp(cinfo->client_data, 1);
}
static pixman_image_t *
load_jpeg(FILE *fp)
{
struct jpeg_decompress_struct cinfo;
struct jpeg_error_mgr jerr;
pixman_image_t *pixman_image = NULL;
unsigned int i;
int stride, first;
JSAMPLE *data, *rows[4];
jmp_buf env;
cinfo.err = jpeg_std_error(&jerr);
jerr.error_exit = error_exit;
cinfo.client_data = env;
if (setjmp(env))
return NULL;
jpeg_create_decompress(&cinfo);
jpeg_stdio_src(&cinfo, fp);
jpeg_read_header(&cinfo, TRUE);
cinfo.out_color_space = JCS_RGB;
jpeg_start_decompress(&cinfo);
stride = cinfo.output_width * 4;
data = malloc(stride * cinfo.output_height);
if (data == NULL) {
fprintf(stderr, "couldn't allocate image data\n");
return NULL;
}
while (cinfo.output_scanline < cinfo.output_height) {
first = cinfo.output_scanline;
for (i = 0; i < ARRAY_LENGTH(rows); i++)
rows[i] = data + (first + i) * stride;
jpeg_read_scanlines(&cinfo, rows, ARRAY_LENGTH(rows));
for (i = 0; first + i < cinfo.output_scanline; i++)
swizzle_row(rows[i], cinfo.output_width);
}
jpeg_finish_decompress(&cinfo);
jpeg_destroy_decompress(&cinfo);
pixman_image = pixman_image_create_bits(PIXMAN_a8r8g8b8,
cinfo.output_width,
cinfo.output_height,
(uint32_t *) data, stride);
pixman_image_set_destroy_function(pixman_image,
pixman_image_destroy_func, data);
return pixman_image;
}
#else
static pixman_image_t *
load_jpeg(FILE *fp)
{
fprintf(stderr, "JPEG support disabled at compile-time\n");
return NULL;
}
#endif
static inline int
multiply_alpha(int alpha, int color)
{
int temp = (alpha * color) + 0x80;
return ((temp + (temp >> 8)) >> 8);
}
static void
premultiply_data(png_structp png,
png_row_infop row_info,
png_bytep data)
{
unsigned int i;
png_bytep p;
for (i = 0, p = data; i < row_info->rowbytes; i += 4, p += 4) {
png_byte alpha = p[3];
uint32_t w;
if (alpha == 0) {
w = 0;
} else {
png_byte red = p[0];
png_byte green = p[1];
png_byte blue = p[2];
if (alpha != 0xff) {
red = multiply_alpha(alpha, red);
green = multiply_alpha(alpha, green);
blue = multiply_alpha(alpha, blue);
}
w = (alpha << 24) | (red << 16) | (green << 8) | (blue << 0);
}
* (uint32_t *) p = w;
}
}
static void
read_func(png_structp png, png_bytep data, png_size_t size)
{
FILE *fp = png_get_io_ptr(png);
if (fread(data, 1, size, fp) != size)
png_error(png, NULL);
}
static void
png_error_callback(png_structp png, png_const_charp error_msg)
{
longjmp (png_jmpbuf (png), 1);
}
static pixman_image_t *
load_png(FILE *fp)
{
png_struct *png;
png_info *info;
png_byte *data = NULL;
png_byte **row_pointers = NULL;
png_uint_32 width, height;
int depth, color_type, interlace, stride;
unsigned int i;
pixman_image_t *pixman_image = NULL;
png = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL,
png_error_callback, NULL);
if (!png)
return NULL;
info = png_create_info_struct(png);
if (!info) {
png_destroy_read_struct(&png, &info, NULL);
return NULL;
}
if (setjmp(png_jmpbuf(png))) {
if (data)
free(data);
if (row_pointers)
free(row_pointers);
png_destroy_read_struct(&png, &info, NULL);
return NULL;
}
png_set_read_fn(png, fp, read_func);
png_read_info(png, info);
png_get_IHDR(png, info,
&width, &height, &depth,
&color_type, &interlace, NULL, NULL);
if (color_type == PNG_COLOR_TYPE_PALETTE)
png_set_palette_to_rgb(png);
if (color_type == PNG_COLOR_TYPE_GRAY)
png_set_expand_gray_1_2_4_to_8(png);
if (png_get_valid(png, info, PNG_INFO_tRNS))
png_set_tRNS_to_alpha(png);
if (depth == 16)
png_set_strip_16(png);
if (depth < 8)
png_set_packing(png);
if (color_type == PNG_COLOR_TYPE_GRAY ||
color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
png_set_gray_to_rgb(png);
if (interlace != PNG_INTERLACE_NONE)
png_set_interlace_handling(png);
png_set_filler(png, 0xff, PNG_FILLER_AFTER);
png_set_read_user_transform_fn(png, premultiply_data);
png_read_update_info(png, info);
png_get_IHDR(png, info,
&width, &height, &depth,
&color_type, &interlace, NULL, NULL);
stride = stride_for_width(width);
data = malloc(stride * height);
if (!data) {
png_destroy_read_struct(&png, &info, NULL);
return NULL;
}
row_pointers = malloc(height * sizeof row_pointers[0]);
if (row_pointers == NULL) {
free(data);
png_destroy_read_struct(&png, &info, NULL);
return NULL;
}
for (i = 0; i < height; i++)
row_pointers[i] = &data[i * stride];
png_read_image(png, row_pointers);
png_read_end(png, info);
free(row_pointers);
png_destroy_read_struct(&png, &info, NULL);
pixman_image = pixman_image_create_bits(PIXMAN_a8r8g8b8,
width, height, (uint32_t *) data, stride);
pixman_image_set_destroy_function(pixman_image,
pixman_image_destroy_func, data);
return pixman_image;
}
#ifdef HAVE_WEBP
static pixman_image_t *
load_webp(FILE *fp)
{
WebPDecoderConfig config;
uint8_t buffer[16 * 1024];
int len;
VP8StatusCode status;
WebPIDecoder *idec;
if (!WebPInitDecoderConfig(&config)) {
fprintf(stderr, "Library version mismatch!\n");
return NULL;
}
/* webp decoding api doesn't seem to specify a min size that's
usable for GetFeatures, but 256 works... */
len = fread(buffer, 1, 256, fp);
status = WebPGetFeatures(buffer, len, &config.input);
if (status != VP8_STATUS_OK) {
fprintf(stderr, "failed to parse webp header\n");
WebPFreeDecBuffer(&config.output);
return NULL;
}
config.output.colorspace = MODE_BGRA;
config.output.u.RGBA.stride = stride_for_width(config.input.width);
config.output.u.RGBA.size =
config.output.u.RGBA.stride * config.input.height;
config.output.u.RGBA.rgba =
malloc(config.output.u.RGBA.stride * config.input.height);
config.output.is_external_memory = 1;
if (!config.output.u.RGBA.rgba) {
WebPFreeDecBuffer(&config.output);
return NULL;
}
rewind(fp);
idec = WebPINewDecoder(&config.output);
if (!idec) {
WebPFreeDecBuffer(&config.output);
return NULL;
}
while (!feof(fp)) {
len = fread(buffer, 1, sizeof buffer, fp);
status = WebPIAppend(idec, buffer, len);
if (status != VP8_STATUS_OK) {
fprintf(stderr, "webp decode status %d\n", status);
WebPIDelete(idec);
WebPFreeDecBuffer(&config.output);
return NULL;
}
}
WebPIDelete(idec);
WebPFreeDecBuffer(&config.output);
return pixman_image_create_bits(PIXMAN_a8r8g8b8,
config.input.width,
config.input.height,
(uint32_t *) config.output.u.RGBA.rgba,
config.output.u.RGBA.stride);
}
#else
static pixman_image_t *
load_webp(FILE *fp)
{
fprintf(stderr, "WebP support disabled at compile-time\n");
return NULL;
}
#endif
struct image_loader {
unsigned char header[4];
int header_size;
pixman_image_t *(*load)(FILE *fp);
};
static const struct image_loader loaders[] = {
{ { 0x89, 'P', 'N', 'G' }, 4, load_png },
{ { 0xff, 0xd8 }, 2, load_jpeg },
{ { 'R', 'I', 'F', 'F' }, 4, load_webp }
};
pixman_image_t *
load_image(const char *filename)
{
pixman_image_t *image = NULL;
unsigned char header[4];
FILE *fp;
unsigned int i;
if (!filename || !*filename)
return NULL;
fp = fopen(filename, "rb");
if (!fp) {
fprintf(stderr, "%s: %s\n", filename, strerror(errno));
return NULL;
}
if (fread(header, sizeof header, 1, fp) != 1) {
fclose(fp);
fprintf(stderr, "%s: unable to read file header\n", filename);
return NULL;
}
rewind(fp);
for (i = 0; i < ARRAY_LENGTH(loaders); i++) {
if (memcmp(header, loaders[i].header,
loaders[i].header_size) == 0) {
image = loaders[i].load(fp);
break;
}
}
fclose(fp);
if (i == ARRAY_LENGTH(loaders)) {
fprintf(stderr, "%s: unrecognized file header "
"0x%02x 0x%02x 0x%02x 0x%02x\n",
filename, header[0], header[1], header[2], header[3]);
} else if (!image) {
/* load probably printed something, but just in case */
fprintf(stderr, "%s: error reading image\n", filename);
}
return image;
}