Support multiple locales string for accept language list

chrome/browser/android/preferences/pref_service_bridge.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 "chrome/browser/android/preferences/pref_service_bridge.h"
 
 #include <jni.h>
 #include <stddef.h>
 
 #include <memory>
@@ skipping 1045 matching lines @@
 
 static void SetEulaAccepted(JNIEnv* env, const JavaParamRef<jobject>& obj) {
   g_browser_process->local_state()->SetBoolean(prefs::kEulaAccepted, true);
 }
 
 static void ResetAcceptLanguages(JNIEnv* env,
                                  const JavaParamRef<jobject>& obj,
                                  const JavaParamRef<jstring>& default_locale) {
   std::string accept_languages(l10n_util::GetStringUTF8(IDS_ACCEPT_LANGUAGES));
   std::string locale_string(ConvertJavaStringToUTF8(env, default_locale));
-
   PrefServiceBridge::PrependToAcceptLanguagesIfNecessary(locale_string,
                                                          &accept_languages);
   GetPrefService()->SetString(prefs::kAcceptLanguages, accept_languages);
 }
 
 // Sends all information about the different versions to Java.
 // From browser_about_handler.cc
 static ScopedJavaLocalRef<jobject> GetAboutVersionStrings(
     JNIEnv* env,
     const JavaParamRef<jobject>& obj) {
@@ skipping 63 matching lines @@
   return RegisterNativesImpl(env);
 }
 
 // static
 // This logic should be kept in sync with prependToAcceptLanguagesIfNecessary in
 // chrome/android/java/src/org/chromium/chrome/browser/
 //     physicalweb/PwsClientImpl.java
 void PrefServiceBridge::PrependToAcceptLanguagesIfNecessary(
     const std::string& locale,
     std::string* accept_languages) {
-  if (locale.size() != 5u || locale[2] != '_')  // not well-formed
-    return;
-
-  std::string language(locale.substr(0, 2));
-  std::string region(locale.substr(3, 2));
-
-  // Java mostly follows ISO-639-1 and ICU, except for the following three.
-  // See documentation on java.util.Locale constructor for more.
-  if (language == "iw") {
-    language = "he";
-  } else if (language == "ji") {
-    language = "yi";
-  } else if (language == "in") {
-    language = "id";
+  std::vector<std::string> lans;

[Seigo Nonaka, 2016/10/05 07:15:41]

probably, languages or langs are preferred.

[Yirui Huang, 2016/10/06 01:17:59]

Done.

+  std::string languages_to_check = locale;
+  // Check see if it is a Locale List or single Locale
+  if (languages_to_check.length() > 5) {

[Seigo Nonaka, 2016/10/05 07:15:41]

Looks like this is not a good condition for checking the input is locale list or
not.
For example, "en,ja" is 5-length string but it is a list of the locales.

[Yirui Huang, 2016/10/06 01:17:59]

Done.

+    while (languages_to_check.find(",") != std::string::npos) {
+      std::size_t bfound = 0;
+      std::size_t efound = languages_to_check.find(",");
+      lans.push_back(languages_to_check.substr(bfound, efound));
+      bfound = efound + 1;
+      languages_to_check = languages_to_check.substr(bfound);

[Seigo Nonaka, 2016/10/05 07:15:41]

Since languages_to_check is a std::string, you create new std::string object for
each while loop.
Instead how about using 2nd argument of the std::string::find method?
http://www.cplusplus.com/reference/string/string/find/

[Yirui Huang, 2016/10/06 01:17:59]

Done.

+      // Check the last element
+      if (languages_to_check.length() <= 5) {

[Seigo Nonaka, 2016/10/05 07:15:41]

Similarly, languages_to_check can be still list even if it is less than 5 chars,
e.g. "en,ja"

[Yirui Huang, 2016/10/06 01:17:59]

Done.

+        lans.push_back(languages_to_check);
+        break;
+      }
+    }
+  } else {
+    lans.push_back(languages_to_check);
   }
 
-  std::string language_region(language + "-" + region);
+  std::vector<std::string> parts;
+  for (std::size_t i = 0; i < lans.size(); i++) {
+    if (lans[i].size() != 5u || lans[i][2] != '_')  // not well-formed
+      continue;
+    std::string language(lans[i].substr(0, 2));
+    std::string region(lans[i].substr(3, 2));
 
-  if (accept_languages->find(language_region) == std::string::npos) {
-    std::vector<std::string> parts;
-    parts.push_back(language_region);
-    // If language is not in the accept languages list, also add language code.
-    // This will work with the IDS_ACCEPT_LANGUAGE localized strings bundled
-    // with Chrome but may fail on arbitrary lists of language tags due to
-    // differences in case and whitespace.
-    if (accept_languages->find(language + ",") == std::string::npos &&
-        !std::equal(language.rbegin(), language.rend(),
-                    accept_languages->rbegin())) {
-      parts.push_back(language);
+    // Java mostly follows ISO-639-1 and ICU, except for the following three.
+    // See documentation on java.util.Locale constructor for more.
+    if (language == "iw") {
+      language = "he";
+    } else if (language == "ji") {
+      language = "yi";
+    } else if (language == "in") {
+      language = "id";
     }
-    parts.push_back(*accept_languages);
-    *accept_languages = base::JoinString(parts, ",");
+
+    std::string language_region(language + "-" + region);
+
+    if (accept_languages->find(language_region) == std::string::npos) {
+      parts.push_back(language_region);
+      // If language is not in the accept languages list, also add language
+      // code.
+      // This will work with the IDS_ACCEPT_LANGUAGE localized strings bundled
+      // with Chrome but may fail on arbitrary lists of language tags due to
+      // differences in case and whitespace.
+      if ((accept_languages->find(language) == std::string::npos ||
+           accept_languages->find(language + ",") == std::string::npos) &&
+          !std::equal(language.rbegin(), language.rend(),
+                      accept_languages->rbegin())) {
+        parts.push_back(language);
+      }
+    }
   }
+  parts.push_back(*accept_languages);
+  *accept_languages = base::JoinString(parts, ",");
 }
 
 // static
 std::string PrefServiceBridge::GetAndroidPermissionForContentSetting(
     ContentSettingsType content_type) {
   JNIEnv* env = AttachCurrentThread();
   base::android::ScopedJavaLocalRef<jstring> android_permission =
       Java_PrefServiceBridge_getAndroidPermissionForContentSetting(
           env, content_type);
   if (android_permission.is_null())
     return std::string();
 
   return ConvertJavaStringToUTF8(android_permission);
 }
 
 static void SetSupervisedUserId(JNIEnv* env,
                                 const JavaParamRef<jobject>& obj,
                                 const JavaParamRef<jstring>& pref) {
   GetPrefService()->SetString(prefs::kSupervisedUserId,
                               ConvertJavaStringToUTF8(env, pref));
 }