Mojo: Set a default value for the --origin command line switch.

mojo/shell/mojo_url_resolver.cc

 // Copyright 2014 The Chromium 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 "mojo/shell/mojo_url_resolver.h"
 
 #include "base/base_paths.h"
 #include "base/files/file_path.h"
 #include "base/logging.h"
 #include "base/path_service.h"
@@ skipping 10 matching lines @@
 #elif defined(OS_LINUX) || defined(OS_ANDROID)
   return "lib" + host_name + ".so";
 #elif defined(OS_MACOSX)
   return host_name + ".so";
 #else
   NOTREACHED() << "dynamic loading of services not supported";
   return std::string();
 #endif
 }
 
+GURL AddTrailingSlashIfNeeded(const GURL& url) {
+  if (!url.has_path() || *url.path().rbegin() == '/')
+    return url;
+
+  std::string path(url.path() + '/');
+  GURL::Replacements replacements;
+  replacements.SetPathStr(path);
+  return url.ReplaceComponents(replacements);
+}
+
 }  // namespace
 
 MojoURLResolver::MojoURLResolver() {
   // Needed to treat first component of mojo URLs as host, not path.
   url::AddStandardScheme("mojo");
+
+  // By default, resolve mojo URLs to files living alongside the shell.
+  base::FilePath path;
+  PathService::Get(base::DIR_MODULE, &path);
+  default_base_url_ = AddTrailingSlashIfNeeded(net::FilePathToFileURL(path));
 }
 
 MojoURLResolver::~MojoURLResolver() {
 }
 
 void MojoURLResolver::SetBaseURL(const GURL& base_url) {
   DCHECK(base_url.is_valid());
-  base_url_ = base_url;
   // Force a trailing slash on the base_url to simplify resolving
   // relative files and URLs below.
-  if (base_url.has_path() && *base_url.path().rbegin() != '/') {
-    std::string path(base_url.path() + '/');
-    GURL::Replacements replacements;
-    replacements.SetPathStr(path);
-    base_url_ = base_url_.ReplaceComponents(replacements);
-  }
+  base_url_ = AddTrailingSlashIfNeeded(base_url);
 }
 
 void MojoURLResolver::AddCustomMapping(const GURL& mojo_url,
                                        const GURL& resolved_url) {
   url_map_[mojo_url] = resolved_url;
 }
 
 void MojoURLResolver::AddLocalFileMapping(const GURL& mojo_url) {
   local_file_set_.insert(mojo_url);
 }
 
 GURL MojoURLResolver::Resolve(const GURL& mojo_url) const {
   std::map<GURL, GURL>::const_iterator it = url_map_.find(mojo_url);
   if (it != url_map_.end())
     return it->second;
 
   std::string lib = MakeSharedLibraryName(mojo_url.host());
 
-  if (local_file_set_.find(mojo_url) != local_file_set_.end()) {
+  if (!base_url_.is_valid() ||
+      local_file_set_.find(mojo_url) != local_file_set_.end()) {
     // Resolve to a local file URL.
-    base::FilePath path;
-    PathService::Get(base::DIR_MODULE, &path);
-    path = path.Append(base::FilePath::FromUTF8Unsafe(lib));
-    return net::FilePathToFileURL(path);
+    return default_base_url_.Resolve(lib);
   }
 
   // Otherwise, resolve to an URL relative to base_url_.
   return base_url_.Resolve(lib);
 }
 
 }  // namespace shell
 }  // namespace mojo