forked from premiere/premiere-libtorrent
418 lines
9.3 KiB
C++
418 lines
9.3 KiB
C++
/*
|
|
|
|
Copyright (c) 2003, Arvid Norberg
|
|
All rights reserved.
|
|
|
|
Redistribution and use in source and binary forms, with or without
|
|
modification, are permitted provided that the following conditions
|
|
are met:
|
|
|
|
* Redistributions of source code must retain the above copyright
|
|
notice, this list of conditions and the following disclaimer.
|
|
* Redistributions in binary form must reproduce the above copyright
|
|
notice, this list of conditions and the following disclaimer in
|
|
the documentation and/or other materials provided with the distribution.
|
|
* Neither the name of the author nor the names of its
|
|
contributors may be used to endorse or promote products derived
|
|
from this software without specific prior written permission.
|
|
|
|
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
|
|
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
POSSIBILITY OF SUCH DAMAGE.
|
|
|
|
*/
|
|
|
|
|
|
#ifndef TORRENT_BENCODE_HPP_INCLUDED
|
|
#define TORRENT_BENCODE_HPP_INCLUDED
|
|
|
|
|
|
|
|
/*
|
|
* This file declares the following functions:
|
|
*
|
|
*----------------------------------
|
|
* template<class OutIt>
|
|
* void libtorrent::bencode(OutIt out, const libtorrent::entry& e);
|
|
*
|
|
* Encodes a message entry with bencoding into the output
|
|
* iterator given. The bencoding is described in the BitTorrent
|
|
* protocol description document OutIt must be an OutputIterator
|
|
* of type char. This may throw libtorrent::invalid_encoding if
|
|
* the entry contains invalid nodes (undefined_t for example).
|
|
*
|
|
*----------------------------------
|
|
* template<class InIt>
|
|
* libtorrent::entry libtorrent::bdecode(InIt start, InIt end);
|
|
*
|
|
* Decodes the buffer given by the start and end iterators
|
|
* and returns the decoded entry. InIt must be an InputIterator
|
|
* of type char. May throw libtorrent::invalid_encoding if
|
|
* the string is not correctly bencoded.
|
|
*
|
|
*/
|
|
|
|
|
|
|
|
|
|
#include <cstdlib>
|
|
|
|
#ifdef _MSC_VER
|
|
#pragma warning(push, 1)
|
|
#endif
|
|
|
|
#include <boost/static_assert.hpp>
|
|
|
|
#ifdef _MSC_VER
|
|
#pragma warning(pop)
|
|
#endif
|
|
|
|
#include "libtorrent/entry.hpp"
|
|
#include "libtorrent/config.hpp"
|
|
|
|
#include "libtorrent/assert.hpp"
|
|
#include "libtorrent/escape_string.hpp"
|
|
|
|
namespace libtorrent
|
|
{
|
|
|
|
struct TORRENT_EXPORT invalid_encoding: std::exception
|
|
{
|
|
virtual const char* what() const throw() { return "invalid bencoding"; }
|
|
};
|
|
|
|
namespace detail
|
|
{
|
|
template <class OutIt>
|
|
int write_string(OutIt& out, const std::string& val)
|
|
{
|
|
for (std::string::const_iterator i = val.begin()
|
|
, end(val.end()); i != end; ++i)
|
|
*out++ = *i;
|
|
return int(val.length());
|
|
}
|
|
|
|
TORRENT_EXPORT char const* integer_to_str(char* buf, int size, entry::integer_type val);
|
|
|
|
template <class OutIt>
|
|
int write_integer(OutIt& out, entry::integer_type val)
|
|
{
|
|
// the stack allocated buffer for keeping the
|
|
// decimal representation of the number can
|
|
// not hold number bigger than this:
|
|
BOOST_STATIC_ASSERT(sizeof(entry::integer_type) <= 8);
|
|
char buf[21];
|
|
int ret = 0;
|
|
for (char const* str = integer_to_str(buf, 21, val);
|
|
*str != 0; ++str)
|
|
{
|
|
*out = *str;
|
|
++out;
|
|
++ret;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
template <class OutIt>
|
|
void write_char(OutIt& out, char c)
|
|
{
|
|
*out = c;
|
|
++out;
|
|
}
|
|
|
|
template <class InIt>
|
|
std::string read_until(InIt& in, InIt end, char end_token, bool& err)
|
|
{
|
|
std::string ret;
|
|
if (in == end)
|
|
{
|
|
err = true;
|
|
return ret;
|
|
}
|
|
while (*in != end_token)
|
|
{
|
|
ret += *in;
|
|
++in;
|
|
if (in == end)
|
|
{
|
|
err = true;
|
|
return ret;
|
|
}
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
template<class InIt>
|
|
void read_string(InIt& in, InIt end, int len, std::string& str, bool& err)
|
|
{
|
|
TORRENT_ASSERT(len >= 0);
|
|
for (int i = 0; i < len; ++i)
|
|
{
|
|
if (in == end)
|
|
{
|
|
err = true;
|
|
return;
|
|
}
|
|
str += *in;
|
|
++in;
|
|
}
|
|
}
|
|
|
|
// returns the number of bytes written
|
|
template<class OutIt>
|
|
int bencode_recursive(OutIt& out, const entry& e)
|
|
{
|
|
int ret = 0;
|
|
switch(e.type())
|
|
{
|
|
case entry::int_t:
|
|
write_char(out, 'i');
|
|
ret += write_integer(out, e.integer());
|
|
write_char(out, 'e');
|
|
ret += 2;
|
|
break;
|
|
case entry::string_t:
|
|
ret += write_integer(out, e.string().length());
|
|
write_char(out, ':');
|
|
ret += write_string(out, e.string());
|
|
ret += 1;
|
|
break;
|
|
case entry::list_t:
|
|
write_char(out, 'l');
|
|
for (entry::list_type::const_iterator i = e.list().begin(); i != e.list().end(); ++i)
|
|
ret += bencode_recursive(out, *i);
|
|
write_char(out, 'e');
|
|
ret += 2;
|
|
break;
|
|
case entry::dictionary_t:
|
|
write_char(out, 'd');
|
|
for (entry::dictionary_type::const_iterator i = e.dict().begin();
|
|
i != e.dict().end(); ++i)
|
|
{
|
|
// write key
|
|
ret += write_integer(out, i->first.length());
|
|
write_char(out, ':');
|
|
ret += write_string(out, i->first);
|
|
// write value
|
|
ret += bencode_recursive(out, i->second);
|
|
ret += 1;
|
|
}
|
|
write_char(out, 'e');
|
|
ret += 2;
|
|
break;
|
|
default:
|
|
// trying to encode a structure with uninitialized values!
|
|
TORRENT_ASSERT_VAL(false, e.type());
|
|
// do nothing
|
|
break;
|
|
}
|
|
return ret;
|
|
}
|
|
|
|
template<class InIt>
|
|
void bdecode_recursive(InIt& in, InIt end, entry& ret, bool& err, int depth)
|
|
{
|
|
if (depth >= 100)
|
|
{
|
|
err = true;
|
|
return;
|
|
}
|
|
|
|
if (in == end)
|
|
{
|
|
err = true;
|
|
#ifdef TORRENT_DEBUG
|
|
ret.m_type_queried = false;
|
|
#endif
|
|
return;
|
|
}
|
|
switch (*in)
|
|
{
|
|
|
|
// ----------------------------------------------
|
|
// integer
|
|
case 'i':
|
|
{
|
|
++in; // 'i'
|
|
std::string val = read_until(in, end, 'e', err);
|
|
if (err) return;
|
|
TORRENT_ASSERT(*in == 'e');
|
|
++in; // 'e'
|
|
ret = entry(entry::int_t);
|
|
char* end_pointer;
|
|
#if defined TORRENT_WINDOWS && !defined TORRENT_MINGW
|
|
ret.integer() = _strtoi64(val.c_str(), &end_pointer, 10);
|
|
#else
|
|
ret.integer() = strtoll(val.c_str(), &end_pointer, 10);
|
|
#endif
|
|
#ifdef TORRENT_DEBUG
|
|
ret.m_type_queried = false;
|
|
#endif
|
|
if (end_pointer == val.c_str())
|
|
{
|
|
err = true;
|
|
return;
|
|
}
|
|
} break;
|
|
|
|
// ----------------------------------------------
|
|
// list
|
|
case 'l':
|
|
{
|
|
ret = entry(entry::list_t);
|
|
++in; // 'l'
|
|
while (*in != 'e')
|
|
{
|
|
ret.list().push_back(entry());
|
|
entry& e = ret.list().back();
|
|
bdecode_recursive(in, end, e, err, depth + 1);
|
|
if (err)
|
|
{
|
|
#ifdef TORRENT_DEBUG
|
|
ret.m_type_queried = false;
|
|
#endif
|
|
return;
|
|
}
|
|
if (in == end)
|
|
{
|
|
err = true;
|
|
#ifdef TORRENT_DEBUG
|
|
ret.m_type_queried = false;
|
|
#endif
|
|
return;
|
|
}
|
|
}
|
|
#ifdef TORRENT_DEBUG
|
|
ret.m_type_queried = false;
|
|
#endif
|
|
TORRENT_ASSERT(*in == 'e');
|
|
++in; // 'e'
|
|
} break;
|
|
|
|
// ----------------------------------------------
|
|
// dictionary
|
|
case 'd':
|
|
{
|
|
ret = entry(entry::dictionary_t);
|
|
++in; // 'd'
|
|
while (*in != 'e')
|
|
{
|
|
entry key;
|
|
bdecode_recursive(in, end, key, err, depth + 1);
|
|
if (err || key.type() != entry::string_t)
|
|
{
|
|
#ifdef TORRENT_DEBUG
|
|
ret.m_type_queried = false;
|
|
#endif
|
|
return;
|
|
}
|
|
entry& e = ret[key.string()];
|
|
bdecode_recursive(in, end, e, err, depth + 1);
|
|
if (err)
|
|
{
|
|
#ifdef TORRENT_DEBUG
|
|
ret.m_type_queried = false;
|
|
#endif
|
|
return;
|
|
}
|
|
if (in == end)
|
|
{
|
|
err = true;
|
|
#ifdef TORRENT_DEBUG
|
|
ret.m_type_queried = false;
|
|
#endif
|
|
return;
|
|
}
|
|
}
|
|
#ifdef TORRENT_DEBUG
|
|
ret.m_type_queried = false;
|
|
#endif
|
|
TORRENT_ASSERT(*in == 'e');
|
|
++in; // 'e'
|
|
} break;
|
|
|
|
// ----------------------------------------------
|
|
// string
|
|
default:
|
|
if (is_digit((unsigned char)*in))
|
|
{
|
|
std::string len_s = read_until(in, end, ':', err);
|
|
if (err)
|
|
{
|
|
#ifdef TORRENT_DEBUG
|
|
ret.m_type_queried = false;
|
|
#endif
|
|
return;
|
|
}
|
|
TORRENT_ASSERT(*in == ':');
|
|
++in; // ':'
|
|
int len = std::atoi(len_s.c_str());
|
|
ret = entry(entry::string_t);
|
|
read_string(in, end, len, ret.string(), err);
|
|
if (err)
|
|
{
|
|
#ifdef TORRENT_DEBUG
|
|
ret.m_type_queried = false;
|
|
#endif
|
|
return;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
err = true;
|
|
#ifdef TORRENT_DEBUG
|
|
ret.m_type_queried = false;
|
|
#endif
|
|
return;
|
|
}
|
|
#ifdef TORRENT_DEBUG
|
|
ret.m_type_queried = false;
|
|
#endif
|
|
}
|
|
}
|
|
}
|
|
|
|
template<class OutIt>
|
|
int bencode(OutIt out, const entry& e)
|
|
{
|
|
return detail::bencode_recursive(out, e);
|
|
}
|
|
|
|
template<class InIt>
|
|
entry bdecode(InIt start, InIt end)
|
|
{
|
|
entry e;
|
|
bool err = false;
|
|
detail::bdecode_recursive(start, end, e, err, 0);
|
|
#ifdef TORRENT_DEBUG
|
|
TORRENT_ASSERT(e.m_type_queried == false);
|
|
#endif
|
|
if (err) return entry();
|
|
return e;
|
|
}
|
|
|
|
template<class InIt>
|
|
entry bdecode(InIt start, InIt end, int& len)
|
|
{
|
|
entry e;
|
|
bool err = false;
|
|
InIt s = start;
|
|
detail::bdecode_recursive(start, end, e, err, 0);
|
|
len = std::distance(s, start);
|
|
TORRENT_ASSERT(len >= 0);
|
|
if (err) return entry();
|
|
return e;
|
|
}
|
|
}
|
|
|
|
#endif // TORRENT_BENCODE_HPP_INCLUDED
|
|
|