gecko/dom/encoding/EncodingUtils.h

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/* 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"
namespace mozilla {
namespace dom {
class EncodingUtils
{
public:
NS_INLINE_DECL_REFCOUNTING(EncodingUtils)
/**
* Implements decode algorithm's step 1 & 2 from Encoding spec.
* http://encoding.spec.whatwg.org/#decode
*
* @param aData, incoming byte stream of data.
* @param aLength, incoming byte stream length.
* @param aRetval, outgoing encoding corresponding to valid data
* byte order mark.
* @return offset after the BOM bytes in byte stream
* where the actual data starts.
*/
static uint32_t IdentifyDataOffset(const char* aData,
const uint32_t aLength,
const char*& aRetval);
/**
* 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.
*
* @param aLabel, incoming label describing charset to be decoded.
* @param aRetEncoding, returning corresponding encoding for label.
* @return false if no encoding was found for label.
* true if valid encoding found.
*/
static bool FindEncodingForLabel(const nsAString& aLabel,
const char*& 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.
*/
static void TrimSpaceCharacters(nsString& aString)
{
aString.Trim(" \t\n\f\r");
}
/* Called to free up Encoding instance. */
static void Shutdown();
protected:
nsDataHashtable<nsStringHashKey, const char *> mLabelsEncodings;
EncodingUtils();
virtual ~EncodingUtils();
static already_AddRefed<EncodingUtils> GetOrCreate();
};
} // dom
} // mozilla
#endif // mozilla_dom_encodingutils_h_