Consolidate image loading code and move to shared/
diff --git a/shared/image-loader.c b/shared/image-loader.c
new file mode 100644
index 0000000..98cc431
--- /dev/null
+++ b/shared/image-loader.c
@@ -0,0 +1,379 @@
+/*
+ * Copyright © 2008-2012 Kristian Høgsberg
+ * Copyright © 2012 Intel Corporation
+ *
+ * Permission to use, copy, modify, distribute, and sell this software and its
+ * documentation for any purpose is hereby granted without fee, provided that
+ * the above copyright notice appear in all copies and that both that copyright
+ * notice and this permission notice appear in supporting documentation, and
+ * that the name of the copyright holders not be used in advertising or
+ * publicity pertaining to distribution of the software without specific,
+ * written prior permission. The copyright holders make no representations
+ * about the suitability of this software for any purpose. It is provided "as
+ * is" without express or implied warranty.
+ *
+ * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+ * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
+ * EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
+ * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
+ * DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
+ * TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE
+ * OF THIS SOFTWARE.
+ */
+
+#include "../config.h"
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <jpeglib.h>
+#include <png.h>
+#include <pixman.h>
+
+#define ARRAY_LENGTH(a) (sizeof (a) / sizeof (a)[0])
+
+#ifdef HAVE_WEBP
+#include <webp/decode.h>
+#endif
+
+static int
+stride_for_width(int width)
+{
+ return width * 4;
+}
+
+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;
+ int stride, i, 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);
+
+ return pixman_image_create_bits(PIXMAN_a8r8g8b8,
+ cinfo.output_width,
+ cinfo.output_height,
+ (uint32_t *) data, stride);
+}
+
+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) < 0)
+ 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;
+
+ 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);
+
+ return pixman_image_create_bits(PIXMAN_a8r8g8b8, width, height,
+ (uint32_t *) data, stride);
+}
+
+#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);
+}
+
+#endif
+
+
+struct image_loader {
+ 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 },
+#ifdef HAVE_WEBP
+ { { 'R', 'I', 'F', 'F' }, 4, load_webp }
+#endif
+};
+
+pixman_image_t *
+load_image(const char *filename)
+{
+ pixman_image_t *image;
+ unsigned char header[4];
+ FILE *fp;
+ int i;
+
+ fp = fopen(filename, "rb");
+ if (fp == NULL)
+ return NULL;
+
+ fread(header, sizeof header, 1, fp);
+ 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, "unrecognized file header for %s: "
+ "0x%02x 0x%02x 0x%02x 0x%02x\n",
+ filename, header[0], header[1], header[2], header[3]);
+ image = NULL;
+ }
+
+ return image;
+}