tdesktop/Telegram/SourceFiles/core/parse_helper.cpp

116 lines
3.5 KiB
C++

/*
This file is part of Telegram Desktop,
the official desktop version of Telegram messaging app, see https://telegram.org
Telegram Desktop is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
It is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
In addition, as a special exception, the copyright holders give permission
to link the code of portions of this program with the OpenSSL library.
Full license: https://github.com/telegramdesktop/tdesktop/blob/master/LICENSE
Copyright (c) 2014-2016 John Preston, https://desktop.telegram.org
*/
#include "stdafx.h"
#include "core/parse_helper.h"
namespace base {
namespace parse {
// inspired by https://github.com/sindresorhus/strip-json-comments
QByteArray stripComments(const QByteArray &content) {
enum class InsideComment {
None,
SingleLine,
MultiLine,
};
auto insideComment = InsideComment::None;
auto insideString = false;
QByteArray result;
auto begin = content.cbegin(), end = content.cend(), offset = begin;
auto feedContent = [&result, &offset, end](const char *ch) {
if (ch > offset) {
if (result.isEmpty()) result.reserve(end - offset - 2);
result.append(offset, ch - offset);
offset = ch;
}
};
auto feedComment = [&result, &offset, end](const char *ch) {
if (ch > offset) {
if (result.isEmpty()) result.reserve(end - offset - 2);
result.append(' ');
offset = ch;
}
};
for (auto ch = offset; ch != end;) {
auto currentChar = *ch;
auto nextChar = (ch + 1 == end) ? 0 : *(ch + 1);
if (insideComment == InsideComment::None && currentChar == '"') {
auto escaped = ((ch > begin) && *(ch - 1) == '\\') && ((ch - 1 < begin) || *(ch - 2) != '\\');
if (!escaped) {
insideString = !insideString;
}
}
if (insideString) {
++ch;
continue;
}
if (insideComment == InsideComment::None && currentChar == '/' && nextChar == '/') {
feedContent(ch);
insideComment = InsideComment::SingleLine;
ch += 2;
} else if (insideComment == InsideComment::SingleLine && currentChar == '\r' && nextChar == '\n') {
feedComment(ch);
ch += 2;
insideComment = InsideComment::None;
} else if (insideComment == InsideComment::SingleLine && currentChar == '\n') {
feedComment(ch);
++ch;
insideComment = InsideComment::None;
} else if (insideComment == InsideComment::None && currentChar == '/' && nextChar == '*') {
feedContent(ch);
ch += 2;
insideComment = InsideComment::MultiLine;
} else if (insideComment == InsideComment::MultiLine && currentChar == '*' && nextChar == '/') {
ch += 2;
feedComment(ch);
insideComment = InsideComment::None;
} else if (insideComment == InsideComment::MultiLine && currentChar == '\r' && nextChar == '\n') {
feedComment(ch);
ch += 2;
feedContent(ch);
} else if (insideComment == InsideComment::MultiLine && currentChar == '\n') {
feedComment(ch);
++ch;
feedContent(ch);
} else {
++ch;
}
}
if (insideComment == InsideComment::MultiLine) {
// unexpected end of content
}
if (insideComment == InsideComment::None && end > offset) {
if (result.isEmpty()) {
return content;
} else {
result.append(offset, end - offset);
}
}
return result;
}
} // namespace parse
} // namespace base