gecko-dev/dom/encoding/EncodingUtils.cpp
2015-05-03 15:32:37 -04:00

106 lines
3.3 KiB
C++

/* -*- 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/. */
#include "mozilla/dom/EncodingUtils.h"
#include "mozilla/ArrayUtils.h" // ArrayLength
#include "nsUConvPropertySearch.h"
#include "nsIUnicodeDecoder.h"
#include "nsIUnicodeEncoder.h"
#include "nsComponentManagerUtils.h"
namespace mozilla {
namespace dom {
static const char* labelsEncodings[][3] = {
#include "labelsencodings.properties.h"
};
static const char* encodingsGroups[][3] = {
#include "encodingsgroups.properties.h"
};
bool
EncodingUtils::FindEncodingForLabel(const nsACString& aLabel,
nsACString& aOutEncoding)
{
// Save aLabel first because it may refer the same string as aOutEncoding.
nsCString label(aLabel);
EncodingUtils::TrimSpaceCharacters(label);
if (label.IsEmpty()) {
aOutEncoding.Truncate();
return false;
}
ToLowerCase(label);
return NS_SUCCEEDED(nsUConvPropertySearch::SearchPropertyValue(
labelsEncodings, ArrayLength(labelsEncodings), label, aOutEncoding));
}
bool
EncodingUtils::FindEncodingForLabelNoReplacement(const nsACString& aLabel,
nsACString& aOutEncoding)
{
if(!FindEncodingForLabel(aLabel, aOutEncoding)) {
return false;
}
if (aOutEncoding.EqualsLiteral("replacement")) {
aOutEncoding.Truncate();
return false;
}
return true;
}
bool
EncodingUtils::IsAsciiCompatible(const nsACString& aPreferredName)
{
// HZ and UTF-7 are no longer in mozilla-central, but keeping them here
// just in case for the benefit of comm-central.
return !(aPreferredName.LowerCaseEqualsLiteral("utf-16") ||
aPreferredName.LowerCaseEqualsLiteral("utf-16be") ||
aPreferredName.LowerCaseEqualsLiteral("utf-16le") ||
aPreferredName.LowerCaseEqualsLiteral("replacement") ||
aPreferredName.LowerCaseEqualsLiteral("hz-gb-2312") ||
aPreferredName.LowerCaseEqualsLiteral("utf-7") ||
aPreferredName.LowerCaseEqualsLiteral("x-imap4-modified-utf7"));
}
already_AddRefed<nsIUnicodeDecoder>
EncodingUtils::DecoderForEncoding(const nsACString& aEncoding)
{
nsAutoCString contractId(NS_UNICODEDECODER_CONTRACTID_BASE);
contractId.Append(aEncoding);
nsCOMPtr<nsIUnicodeDecoder> decoder = do_CreateInstance(contractId.get());
MOZ_ASSERT(decoder, "Tried to create decoder for unknown encoding.");
return decoder.forget();
}
already_AddRefed<nsIUnicodeEncoder>
EncodingUtils::EncoderForEncoding(const nsACString& aEncoding)
{
nsAutoCString contractId(NS_UNICODEENCODER_CONTRACTID_BASE);
contractId.Append(aEncoding);
nsCOMPtr<nsIUnicodeEncoder> encoder = do_CreateInstance(contractId.get());
MOZ_ASSERT(encoder, "Tried to create encoder for unknown encoding.");
return encoder.forget();
}
void
EncodingUtils::LangGroupForEncoding(const nsACString& aEncoding,
nsACString& aOutGroup)
{
if (NS_FAILED(nsUConvPropertySearch::SearchPropertyValue(
encodingsGroups, ArrayLength(encodingsGroups), aEncoding, aOutGroup))) {
aOutGroup.AssignLiteral("x-unicode");
}
}
} // namespace dom
} // namespace mozilla