intl/strres/nsIStringBundle.idl
author Nicholas Nethercote <nnethercote@mozilla.com>
Wed, 12 Jul 2017 15:13:37 +1000
changeset 417515 129793760f2d718ed61ba17d9aacd57c7ec6785b
parent 217665 0d7d58108070f7fae8f149e9f5b4209bec8bee12
child 422652 e26e9804c545afcb33549da0f7fd693cc3fc671f
permissions -rw-r--r--
Bug 1380227 - Avoid many UTF16toUTF8 and UTF8toUTF16 conversions in nsStringBundle. r=emk. Most of the names passed to nsIStringBundle::{Get,Format}StringFromUTF8Name have one of the two following forms: - a 16-bit C string literal, which is then converted to an 8-bit string in order for the lookup to occur; - an 8-bit C string literal converted to a 16-bit string, which is then converted back to an 8-bit string in order for the lookup to occur. This patch introduces and uses alternative methods that can take an 8-bit C string literal, which requires changing some signatures in other methods and functions. It replaces all C++ uses of the old methods. The patch also changes the existing {Get,Format}StringFromName() methods so they take an AUTF8String argument for the name instead of a wstring, because that's nicer for JS code. Even though there is a method for C++ code and a different one for JS code, |binaryname| is used so that the existing method names can be used for the common case in both languages. The change reduces the number of NS_ConvertUTF8toUTF16 and NS_ConvertUTF16toUTF8 conversions while running Speedometer v2 from ~270,000 to ~160,000. (Most of these conversions involved the string "deprecatedReferrerDirective" in nsCSPParser.cpp.)

/* -*- Mode: IDL; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "nsISupports.idl"
#include "nsISimpleEnumerator.idl"

%{C++

// Define Contractid and CID
// {D85A17C1-AA7C-11d2-9B8C-00805F8A16D9}
#define NS_STRINGBUNDLESERVICE_CID \
{ 0xd85a17c1, 0xaa7c, 0x11d2, \
  { 0x9b, 0x8c, 0x0, 0x80, 0x5f, 0x8a, 0x16, 0xd9 } }

#define NS_STRINGBUNDLE_CONTRACTID "@mozilla.org/intl/stringbundle;1"

/** 
 * observer needs to check if the bundle handle matches
 */
#define NS_STRBUNDLE_LOADED_TOPIC "strbundle-loaded"

%}

native nsStrBundleLoadedFunc(nsStrBundleLoadedFunc);

[scriptable, uuid(D85A17C2-AA7C-11d2-9B8C-00805F8A16D9)]
interface nsIStringBundle : nsISupports
{
  wstring GetStringFromID(in long aID);

  // This method is mostly used from JS, where AUTF8String is appropriate.
  [binaryname(GetStringFromAUTF8Name)]
  wstring GetStringFromName(in AUTF8String aName);

  // This method is mostly used from C++, where |string| is appropriate because
  // the names are most often 8-bit string literals (normally ASCII, though
  // u8"foo" literals will also work).
  [noscript, binaryname(GetStringFromName)]
  wstring GetStringFromNameCpp(in string aName);

  // this is kind of like smprintf - except that you can
  // only pass it unicode strings, using the %S formatting character.
  // the id or name should refer to a string in the bundle that
  // uses %S.. do NOT try to use any other types.
  // this uses nsTextFormatter::smprintf to do the dirty work.
  wstring formatStringFromID(in long aID,
                             [array, size_is(length)] in wstring params,
                             in unsigned long length);

  // This method is mostly used from JS, where AUTF8String is appropriate.
  [binaryname(FormatStringFromAUTF8Name)]
  wstring formatStringFromName(in AUTF8String aName,
                               [array, size_is(length)] in wstring params,
                               in unsigned long length);

  // This method is mostly used from C++, where |string| is appropriate because
  // the names are most often 8-bit string literals (normally ASCII, though
  // u8"foo" literals will also work).
  [noscript, binaryname(FormatStringFromName)]
  wstring formatStringFromNameCpp(in string aName,
                                  [array, size_is(length)] in wstring params,
                                  in unsigned long length);

  /*
  Implements nsISimpleEnumerator, replaces nsIEnumerator 
  */
  nsISimpleEnumerator getSimpleEnumeration();

};

[scriptable, uuid(D85A17C0-AA7C-11d2-9B8C-00805F8A16D9)]
interface nsIStringBundleService : nsISupports
{
  nsIStringBundle createBundle(in string aURLSpec);
  nsIStringBundle createExtensibleBundle(in string aRegistryKey);

  /**
   * Formats a message string from a status code and status arguments.
   * @param aStatus - The status code. This is mapped into a string ID and
   *            and used in the string lookup process (see nsIErrorService).
   * @param aStatusArg - The status message argument(s). Multiple arguments
   *            can be separated by newline ('\n') characters.
   * @return the formatted message
   */
  wstring formatStatusMessage(in nsresult aStatus, in wstring aStatusArg);

  /**
   * flushes the string bundle cache - useful when the locale changes or
   * when we need to get some extra memory back
   * 
   * at some point, we might want to make this flush all the bundles,
   * because any bundles that are floating around when the locale changes
   * will suddenly contain bad data
   *
   */
  void flushBundles();
};