Allow yaml file to specify default compression for images

utility/bmpblk_util.c

 // Copyright (c) 2010 The Chromium OS Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include <errno.h>
 #include <fcntl.h>
 #include <limits.h>
 #include <lzma.h>
 #include <stdio.h>
 #include <string.h>
@@ skipping 246 matching lines @@
     printf("  version %d.%d\n", hdr->major_version, hdr->minor_version);
     printf("  %d screens\n", hdr->number_of_screenlayouts);
     printf("  %d localizations\n", hdr->number_of_localizations);
     printf("  %d discrete images\n", hdr->number_of_imageinfos);
     discard_file(ptr, length);
     return 0;
   }
 
   // Write out yaml
   fprintf(yfp, "bmpblock: %d.%d\n", hdr->major_version, hdr->minor_version);
-  fprintf(yfp, "images:\n");
   offset = sizeof(BmpBlockHeader) +
     (sizeof(ScreenLayout) *
      hdr->number_of_localizations *
      hdr->number_of_screenlayouts);
+  // FIXME(chromium-os:12134): The bmbblock structure allows each image to be
+  // compressed differently, but we haven't provided a way for the yaml file to
+  // specify that. Additionally, we allow the yaml file to specify a default
+  // compression scheme for all images, but only if that line appears in the
+  // yaml file before any images. Accordingly, we'll just check the first image
+  // to see if it has any compression, and if it does, we'll write that out as
+  // the default. When this bug is fixed, we should just write each image's
+  // compression setting separately.
+  img = (ImageInfo *)(ptr + offset);
+  if (img->compression)
+    fprintf(yfp, "compression: %d\n", img->compression);
+  fprintf(yfp, "images:\n");
   for(i=0; i<hdr->number_of_imageinfos; i++) {
     img = (ImageInfo *)(ptr + offset);
     sprintf(image_name, "img_%08x.bmp", offset);
     fprintf(yfp, "  img_%08x: %s  # %dx%d  %d/%d\n", offset, image_name,
             img->width, img->height,
             img->compressed_size, img->original_size);
     if (todir) {
       sprintf(full_path_name, "%s/%s", todir, image_name);
       bfd = open(full_path_name,
                  O_WRONLY | O_CREAT | O_TRUNC | (overwrite ? 0 : O_EXCL),
@@ skipping 100 matching lines @@
   }
 
   if (todir)
     fclose(yfp);
 
   discard_file(ptr, length);
 
   return 0;
 }