/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */ /* vim: set ts=8 sts=2 et sw=2 tw=80: */ /* 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/. */ #ifndef mozilla_dom_encodingutils_h_ #define mozilla_dom_encodingutils_h_ #include "nsDataHashtable.h" #include "nsString.h" class nsIUnicodeDecoder; class nsIUnicodeEncoder; namespace mozilla { namespace dom { class EncodingUtils { public: /** * Implements get an encoding algorithm from Encoding spec. * http://encoding.spec.whatwg.org/#concept-encoding-get * Given a label, this function returns the corresponding encoding or a * false. * The returned name may not be lowercased due to compatibility with * our internal implementations. * * @param aLabel, incoming label describing charset to be decoded. * @param aOutEncoding, returning corresponding encoding for label. * @return false if no encoding was found for label. * true if valid encoding found. */ static bool FindEncodingForLabel(const nsACString& aLabel, nsACString& aOutEncoding); static bool FindEncodingForLabel(const nsAString& aLabel, nsACString& aOutEncoding) { return FindEncodingForLabel(NS_ConvertUTF16toUTF8(aLabel), aOutEncoding); } /** * Like FindEncodingForLabel() except labels that map to "replacement" * are treated as unknown. * * @param aLabel, incoming label describing charset to be decoded. * @param aOutEncoding, returning corresponding encoding for label. * @return false if no encoding was found for label. * true if valid encoding found. */ static bool FindEncodingForLabelNoReplacement(const nsACString& aLabel, nsACString& aOutEncoding); static bool FindEncodingForLabelNoReplacement(const nsAString& aLabel, nsACString& aOutEncoding) { return FindEncodingForLabelNoReplacement(NS_ConvertUTF16toUTF8(aLabel), aOutEncoding); } /** * Remove any leading and trailing space characters, following the * definition of space characters from Encoding spec. * http://encoding.spec.whatwg.org/#terminology * Note that nsAString::StripWhitespace() doesn't exactly match the * definition. It also removes all matching chars in the string, * not just leading and trailing. * * @param aString, string to be trimmed. */ template<class T> static void TrimSpaceCharacters(T& aString) { aString.Trim(" \t\n\f\r"); } /** * Check is the encoding is ASCII-compatible in the sense that Basic Latin * encodes to ASCII bytes. (The reverse may not be true!) * * @param aPreferredName a preferred encoding label * @return whether the encoding is ASCII-compatible */ static bool IsAsciiCompatible(const nsACString& aPreferredName); /** * Instantiates a decoder for an encoding. The input must be a * Gecko-canonical encoding name. * @param aEncoding a Gecko-canonical encoding name * @return a decoder */ static already_AddRefed<nsIUnicodeDecoder> DecoderForEncoding(const char* aEncoding) { nsDependentCString encoding(aEncoding); return DecoderForEncoding(encoding); } /** * Instantiates a decoder for an encoding. The input must be a * Gecko-canonical encoding name * @param aEncoding a Gecko-canonical encoding name * @return a decoder */ static already_AddRefed<nsIUnicodeDecoder> DecoderForEncoding(const nsACString& aEncoding); /** * Instantiates an encoder for an encoding. The input must be a * Gecko-canonical encoding name. * @param aEncoding a Gecko-canonical encoding name * @return an encoder */ static already_AddRefed<nsIUnicodeEncoder> EncoderForEncoding(const char* aEncoding) { nsDependentCString encoding(aEncoding); return EncoderForEncoding(encoding); } /** * Instantiates an encoder for an encoding. The input must be a * Gecko-canonical encoding name. * @param aEncoding a Gecko-canonical encoding name * @return an encoder */ static already_AddRefed<nsIUnicodeEncoder> EncoderForEncoding(const nsACString& aEncoding); /** * Finds a Gecko language group string (e.g. x-western) for a Gecko-canonical * encoding name. * * @param aEncoding, incoming label describing charset to be decoded. * @param aOutGroup, returning corresponding language group. */ static void LangGroupForEncoding(const nsACString& aEncoding, nsACString& aOutGroup); private: EncodingUtils() = delete; }; } // namespace dom } // namespace mozilla #endif // mozilla_dom_encodingutils_h_