79 lines
1.8 KiB
C++
79 lines
1.8 KiB
C++
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// Copyright 2014 The Chromium Authors. All rights reserved.
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// Use of this source code is governed by a BSD-style license that can be
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// found in the LICENSE file.
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#include "media/formats/webm/webm_webvtt_parser.h"
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namespace media {
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void WebMWebVTTParser::Parse(const uint8* payload, int payload_size,
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std::string* id,
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std::string* settings,
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std::string* content) {
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WebMWebVTTParser parser(payload, payload_size);
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parser.Parse(id, settings, content);
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}
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WebMWebVTTParser::WebMWebVTTParser(const uint8* payload, int payload_size)
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: ptr_(payload),
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ptr_end_(payload + payload_size) {
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}
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void WebMWebVTTParser::Parse(std::string* id,
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std::string* settings,
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std::string* content) {
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ParseLine(id);
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ParseLine(settings);
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content->assign(ptr_, ptr_end_);
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}
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bool WebMWebVTTParser::GetByte(uint8* byte) {
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if (ptr_ >= ptr_end_)
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return false; // indicates end-of-stream
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*byte = *ptr_++;
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return true;
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}
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void WebMWebVTTParser::UngetByte() {
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--ptr_;
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}
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void WebMWebVTTParser::ParseLine(std::string* line) {
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line->clear();
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// Consume characters from the stream, until we reach end-of-line.
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// The WebVTT spec states that lines may be terminated in any of the following
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// three ways:
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// LF
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// CR
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// CR LF
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// The spec is here:
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// http://wiki.webmproject.org/webm-metadata/temporal-metadata/webvtt-in-webm
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enum {
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kLF = '\x0A',
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kCR = '\x0D'
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};
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for (;;) {
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uint8 byte;
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if (!GetByte(&byte) || byte == kLF)
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return;
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if (byte == kCR) {
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if (GetByte(&byte) && byte != kLF)
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UngetByte();
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return;
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}
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line->push_back(byte);
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}
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}
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} // namespace media
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