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Diffstat (limited to 'libktorrent/torrent/bdecoder.cpp')
| -rw-r--r-- | libktorrent/torrent/bdecoder.cpp | 224 |
1 files changed, 224 insertions, 0 deletions
diff --git a/libktorrent/torrent/bdecoder.cpp b/libktorrent/torrent/bdecoder.cpp new file mode 100644 index 0000000..6c5a179 --- /dev/null +++ b/libktorrent/torrent/bdecoder.cpp @@ -0,0 +1,224 @@ +/*************************************************************************** + * Copyright (C) 2005 by Joris Guisson * + * joris.guisson@gmail.com * + * * + * 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. * + ***************************************************************************/ +#include <util/log.h> +#include <util/error.h> +#include <klocale.h> +#include "bdecoder.h" +#include "bnode.h" +#include "globals.h" + +namespace bt +{ + + BDecoder::BDecoder(const QByteArray & data,bool verbose,Uint32 off) + : data(data),pos(off),verbose(verbose) + { + } + + + BDecoder::~BDecoder() + {} + + BNode* BDecoder::decode() + { + if (pos >= data.size()) + return 0; + + if (data[pos] == 'd') + { + return parseDict(); + } + else if (data[pos] == 'l') + { + return parseList(); + } + else if (data[pos] == 'i') + { + return parseInt(); + } + else if (data[pos] >= '0' && data[pos] <= '9') + { + return parseString(); + } + else + { + throw Error(i18n("Illegal token: %1").arg(data[pos])); + } + } + + BDictNode* BDecoder::parseDict() + { + Uint32 off = pos; + // we're now entering a dictionary + BDictNode* curr = new BDictNode(off); + pos++; + if (verbose) Out() << "DICT" << endl; + try + { + while (pos < data.size() && data[pos] != 'e') + { + if (verbose) Out() << "Key : " << endl; + BNode* kn = decode(); + BValueNode* k = dynamic_cast<BValueNode*>(kn); + if (!k || k->data().getType() != Value::STRING) + { + delete kn; + throw Error(i18n("Decode error")); + } + + QByteArray key = k->data().toByteArray(); + delete kn; + + BNode* data = decode(); + curr->insert(key,data); + } + pos++; + } + catch (...) + { + delete curr; + throw; + } + if (verbose) Out() << "END" << endl; + curr->setLength(pos - off); + return curr; + } + + BListNode* BDecoder::parseList() + { + Uint32 off = pos; + if (verbose) Out() << "LIST" << endl; + BListNode* curr = new BListNode(off); + pos++; + try + { + while (pos < data.size() && data[pos] != 'e') + { + BNode* n = decode(); + curr->append(n); + } + pos++; + } + catch (...) + { + delete curr; + throw; + } + if (verbose) Out() << "END" << endl; + curr->setLength(pos - off); + return curr; + } + + BValueNode* BDecoder::parseInt() + { + Uint32 off = pos; + pos++; + QString n; + // look for e and add everything between i and e to n + while (pos < data.size() && data[pos] != 'e') + { + n += data[pos]; + pos++; + } + + // check if we aren't at the end of the data + if (pos >= data.size()) + { + throw Error(i18n("Unexpected end of input")); + } + + // try to decode the int + bool ok = true; + int val = 0; + val = n.toInt(&ok); + if (ok) + { + pos++; + if (verbose) Out() << "INT = " << val << endl; + BValueNode* vn = new BValueNode(Value(val),off); + vn->setLength(pos - off); + return vn; + } + else + { + Int64 bi = 0LL; + bi = n.toLongLong(&ok); + if (!ok) + throw Error(i18n("Cannot convert %1 to an int").arg(n)); + + pos++; + if (verbose) Out() << "INT64 = " << n << endl; + BValueNode* vn = new BValueNode(Value(bi),off); + vn->setLength(pos - off); + return vn; + } + } + + BValueNode* BDecoder::parseString() + { + Uint32 off = pos; + // string are encoded 4:spam (length:string) + + // first get length by looking for the : + QString n; + while (pos < data.size() && data[pos] != ':') + { + n += data[pos]; + pos++; + } + // check if we aren't at the end of the data + if (pos >= data.size()) + { + throw Error(i18n("Unexpected end of input")); + } + + // try to decode length + bool ok = true; + int len = 0; + len = n.toInt(&ok); + if (!ok) + { + throw Error(i18n("Cannot convert %1 to an int").arg(n)); + } + // move pos to the first part of the string + pos++; + if (pos + len > data.size()) + throw Error(i18n("Torrent is incomplete!")); + + QByteArray arr(len); + for (unsigned int i = pos;i < pos + len;i++) + arr.at(i-pos) = data[i]; + pos += len; + // read the string into n + + // pos should be positioned right after the string + BValueNode* vn = new BValueNode(Value(arr),off); + vn->setLength(pos - off); + if (verbose) + { + if (arr.size() < 200) + Out() << "STRING " << QString(arr) << endl; + else + Out() << "STRING " << "really long string" << endl; + } + return vn; + } +} + |