Treat bad values passed to --images as a fatal error

dm/DM.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "CrashHandler.h"
 #include "DMJsonWriter.h"
 #include "DMSrcSink.h"
@@ skipping 500 matching lines @@
         const char* path = FLAGS_skps[i];
         if (sk_isdir(path)) {
             SkOSFile::Iter it(path, "skp");
             for (SkString file; it.next(&file); ) {
                 push_src("skp", "", new SKPSrc(SkOSPath::Join(path, file.c_str())));
             }
         } else {
             push_src("skp", "", new SKPSrc(path));
         }
     }
-    static const char* const exts[] = {
-        "bmp", "gif", "jpg", "jpeg", "png", "webp", "ktx", "astc", "wbmp", "ico",
-        "BMP", "GIF", "JPG", "JPEG", "PNG", "WEBP", "KTX", "ASTC", "WBMP", "ICO",
-    };
-    for (int i = 0; i < FLAGS_images.count(); i++) {
-        const char* flag = FLAGS_images[i];
-        if (sk_isdir(flag)) {
-            for (size_t j = 0; j < SK_ARRAY_COUNT(exts); j++) {
-                SkOSFile::Iter it(flag, exts[j]);
-                for (SkString file; it.next(&file); ) {
-                    SkString path = SkOSPath::Join(flag, file.c_str());
-                    push_src("image", "decode", new ImageSrc(path)); // Decode entire image
-                    push_codec_srcs(path);
-                    if (brd_supported(exts[j])) {
-                        push_brd_srcs(path);
-                    }
-                }
-            }
-        } else if (sk_exists(flag)) {
-            // assume that FLAGS_images[i] is a valid image if it is a file.
-            push_src("image", "decode", new ImageSrc(flag)); // Decode entire image.
-            push_codec_srcs(flag);
-            push_brd_srcs(flag);
+
+    SkTArray<SkString> images;
+    SkCommonFlags::collectImages(&images);
+    for (auto image : images) {
+        push_src("image", "decode", new ImageSrc(image)); // Decode entire image
+        push_codec_srcs(image);
+        const char* ext = "";
+        int index = image.findLastOf('.');
+        if (index >= 0 && (size_t) ++index < image.size()) {
+            ext = &image.c_str()[index];
+        }
+        if (brd_supported(ext)) {
+            push_brd_srcs(image);
         }
     }
 }
 
 static void push_sink(const SkCommandLineConfig& config, Sink* s) {
     SkAutoTDelete<Sink> sink(s);
 
     // Try a simple Src as a canary.  If it fails, skip this sink.
     struct : public Src {
         Error draw(SkCanvas* c) const override {
@@ skipping 690 matching lines @@
                                                            Reporter* reporter,
                                                            GrContextFactory* factory);
 } // namespace skiatest
 
 #if !defined(SK_BUILD_FOR_IOS)
 int main(int argc, char** argv) {
     SkCommandLineFlags::Parse(argc, argv);
     return dm_main();
 }
 #endif