ServiceWorker: Scope should match url in longest-prefix-match way (won't commit)

content/browser/service_worker/service_worker_utils.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 "content/browser/service_worker/service_worker_utils.h"
 
+#include <string>
+
 #include "base/command_line.h"
 #include "base/logging.h"
 #include "content/public/common/content_switches.h"
+#include "url/gurl.h"
 
 namespace content {
 
 // static
 bool ServiceWorkerUtils::IsFeatureEnabled() {
   static bool enabled = CommandLine::ForCurrentProcess()->HasSwitch(
       switches::kEnableServiceWorker);
   return enabled;
 }
 
 // static
 bool ServiceWorkerUtils::ScopeMatches(const GURL& scope, const GURL& url) {
   DCHECK(!scope.has_ref());
   DCHECK(!url.has_ref());
   const std::string& scope_spec = scope.spec();
   const std::string& url_spec = url.spec();
 
   size_t len = scope_spec.size();
   if (len > 0 && scope_spec[len - 1] == '*')
     return scope_spec.compare(0, len - 1, url_spec, 0, len - 1) == 0;
   return scope_spec == url_spec;
 }
 
+bool ServiceWorkerUtils::FindLongestScopeMatch(
+    const std::vector<GURL>& scopes, const GURL& url, size_t* pos) {
+  DCHECK(!url.has_ref());
+  DCHECK(pos);
+
+  bool found = false;
+  for (size_t i = 0; i < scopes.size(); ++i) {
+    if (!ScopeMatches(scopes[i], url))
+      continue;
+    if (!found || scopes.at(*pos) < scopes.at(i)) {
+      *pos = i;
+      found = true;
+    }
+  }
+  return found;
+}
+
 }  // namespace content