aria2/src/GenericParser.h

117 lines
3.6 KiB
C++

/* <!-- copyright */
/*
* aria2 - The high speed download utility
*
* Copyright (C) 2012 Tatsuhiro Tsujikawa
*
* This program 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 2 of the License, or
* (at your option) any later version.
*
* This program 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.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
* In addition, as a special exception, the copyright holders give
* permission to link the code of portions of this program with the
* OpenSSL library under certain conditions as described in each
* individual source file, and distribute linked combinations
* including the two.
* You must obey the GNU General Public License in all respects
* for all of the code used other than OpenSSL. If you modify
* file(s) with this exception, you may extend this exception to your
* version of the file(s), but you are not obligated to do so. If you
* do not wish to do so, delete this exception statement from your
* version. If you delete this exception statement from all source
* files in the program, then also delete it here.
*/
/* copyright --> */
#ifndef D_GENERIC_PARSER_H
#define D_GENERIC_PARSER_H
#include "common.h"
#include "SharedHandle.h"
#include "a2io.h"
#include "util.h"
namespace aria2 {
template<typename Parser, typename ParserStateMachine>
class GenericParser {
public:
GenericParser()
: parser_(&psm_)
{}
~GenericParser()
{}
typedef typename ParserStateMachine::ResultType ResultType;
typedef ParserStateMachine ParserStateMachineType;
// Parses |size| bytes of data |data| and returns the number of
// bytes processed. On error, one of the negative error codes is
// returned.
ssize_t parseUpdate(const char* data, size_t size)
{
return parser_.parseUpdate(data, size);
}
// Parses |size| bytes of data |data| and returns result. On error,
// null value is returned. On success, the |error| will be the
// number of bytes processed (>= 0). On error, it will be one of the
// negative error code. This function also resets underlying parser
// facility and make it ready to reuse.
ResultType
parseFinal(const char* data, size_t size, ssize_t& error)
{
ResultType res;
error = parser_.parseFinal(data, size);
if(error < 0) {
res = ParserStateMachine::noResult();
} else {
res = psm_.getResult();
}
parser_.reset();
return res;
}
private:
ParserStateMachine psm_;
Parser parser_;
};
template<typename Parser>
typename Parser::ResultType parseFile(Parser& parser,
const std::string& filename)
{
int fd;
// TODO Overrode a2open(const char*,..) and a2open(const std::wstring&,..)
while((fd = a2open(utf8ToWChar(filename).c_str(),
O_BINARY | O_RDONLY, OPEN_MODE)) == -1
&& errno != EINTR);
if(fd == -1) {
return Parser::ParserStateMachineType::noResult();
}
auto_delete_r<int, int> fdDeleter(fd, close);
char buf[4096];
ssize_t nread;
ssize_t nproc;
while((nread = read(fd, buf, sizeof(buf))) > 0) {
nproc = parser.parseUpdate(buf, nread);
if(nproc < 0) {
break;
}
}
return parser.parseFinal(0, 0, nproc);
}
} // namespace aria2
#endif // D_GENERIC_PARSER_H