webp: intial support for WebP images, using libwebp

5 files changed, 97 insertions, 2 deletions

diff --git a/main.c b/main.c
index e3bdaae..1e3c237 100644
--- a/main.c
+++ b/main.c
@@ -29,6 +29,9 @@
 #if defined(WBG_HAVE_JPG)
  #include "jpg.h"
 #endif
+#if defined(WBG_HAVE_WEBP)
+ #include "webp.h"
+#endif
 
 /* Top-level globals */
 static struct wl_display *display;
@@ -366,6 +369,10 @@ main(int argc, const char *const *argv)
     if (image == NULL)
         image = png_load(fp, image_path);
 #endif
+#if defined(WBG_HAVE_WEBP)
+    if (image == NULL)
+        image = webp_load(fp, image_path);
+#endif
     if (image == NULL) {
         fprintf(stderr, "error: %s: failed to load\n", image_path);
         fclose(fp);
diff --git a/meson.build b/meson.build
index 47c6155..4668cd7 100644
--- a/meson.build
+++ b/meson.build
@@ -49,8 +49,9 @@ endif
 pixman = dependency('pixman-1')
 png = dependency('libpng', required: get_option('png'))
 jpg = dependency('libjpeg', required: get_option('jpeg'))
+webp = dependency('libwebp', required: get_option('webp'))
 
-if not png.found() and not jpg.found()
+if not png.found() and not jpg.found() and not webp.found()
   error('you must enable at least one image format')
 endif
 
@@ -60,6 +61,9 @@ endif
 if jpg.found()
   add_project_arguments('-DWBG_HAVE_JPG=1', language:'c')
 endif
+if webp.found()
+  add_project_arguments('-DWBG_HAVE_WEBP=1', language:'c')
+endif
 
 wayland_protocols = dependency('wayland-protocols')
 wayland_client = dependency('wayland-client')
@@ -106,6 +110,9 @@ endif
 if jpg.found()
   image_format_sources += ['jpg.c', 'jpg.h']
 endif
+if webp.found()
+  image_format_sources += ['webp.c', 'webp.h']
+endif
 
 executable(
     'wbg',
@@ -115,13 +122,14 @@ executable(
     'stride.h',
     image_format_sources,
     wl_proto_src + wl_proto_headers, version,
-    dependencies: [pixman, png, jpg, wayland_client, tllist],
+    dependencies: [pixman, png, jpg, webp, wayland_client, tllist],
     install: true)
 
 summary(
   {
     'PNG support': png.found(),
     'JPEG support': jpg.found(),
+    'WebP support': webp.found(),
   },
   bool_yn: true
 )
diff --git a/meson_options.txt b/meson_options.txt
index 6818e93..db77d13 100644
--- a/meson_options.txt
+++ b/meson_options.txt
@@ -1,2 +1,3 @@
 option('png', type: 'feature')
 option('jpeg', type: 'feature')
+option('webp', type: 'feature')
diff --git a/webp.c b/webp.c
new file mode 100644
index 0000000..82aa493
--- /dev/null
+++ b/webp.c
@@ -0,0 +1,73 @@
+#include "webp.h"
+#include <stdlib.h>
+#include <stdio.h>
+
+#include <webp/decode.h>
+
+#define LOG_MODULE "webp"
+#define LOG_ENABLE_DBG 0
+#include "log.h"
+#include "stride.h"
+
+pixman_image_t *
+webp_load(FILE *fp, const char *path)
+{
+    uint8_t *file_data = NULL;
+    uint8_t *image_data = NULL;
+    size_t image_size;
+    pixman_image_t *pix = NULL;
+    pixman_format_code_t format;
+    int width, height, stride;
+
+    if (fseek(fp, 0, SEEK_END) < 0) {
+        LOG_ERRNO("%s: failed to seek to end of file", path);
+        return NULL;
+    }
+    image_size = ftell(fp);
+    if (fseek(fp, 0, SEEK_SET) < 0) {
+        LOG_ERRNO("%s: failed to seek to beginning of file", path);
+        return NULL;
+    }
+
+    if (!(file_data = WebPMalloc(image_size + 1))) {
+        goto err;
+    }
+
+    clearerr(fp);
+    fread(file_data, image_size, 1, fp);
+    if (ferror(fp)) {
+        LOG_ERRNO("%s: failed to read", path);
+        goto err;
+    }
+    file_data[image_size] = '\0';
+
+    /* Verify it is a webp image */
+    if (!WebPGetInfo(file_data, image_size, NULL, NULL)) {
+        LOG_ERR("%s: not a WebP file", path);
+        goto err;
+    }
+
+    image_data = WebPDecodeRGBA(file_data, image_size, &width, &height);
+    if (image_data == NULL) {
+        goto err;
+    }
+    format = PIXMAN_x8b8g8r8;
+    stride = stride_for_format_and_width(format, width);
+
+    pix = pixman_image_create_bits_no_clear(
+        format, width, height, (uint32_t *)image_data, stride);
+
+    if (pix == NULL) {
+        LOG_ERR("%s: failed to instantiate pixman image", path);
+        goto err;
+    }
+
+    WebPFree(file_data);
+    return pix;
+
+err:
+    WebPFree(file_data);
+    WebPFree(image_data);
+
+    return NULL;
+}
diff --git a/webp.h b/webp.h
new file mode 100644
index 0000000..2638cd2
--- /dev/null
+++ b/webp.h
@@ -0,0 +1,6 @@
+#pragma once
+
+#include <stdio.h>
+#include <pixman.h>
+
+pixman_image_t *webp_load(FILE *fp, const char *path);