Added stream Bencode parser

4 files changed, 567 insertions, 1 deletions

diff --git a/src/BencodeParser.cc b/src/BencodeParser.cc
new file mode 100644
index 00000000..63585784
--- /dev/null
+++ b/src/BencodeParser.cc
@@ -0,0 +1,407 @@
+/* <!-- 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 --> */
+#include "BencodeParser.h"
+#include "StructParserStateMachine.h"
+#include "util.h"
+
+namespace aria2 {
+
+namespace bittorrent {
+
+namespace {
+enum {
+  BENCODE_FINISH,
+  BENCODE_ERROR,
+  BENCODE_INITIAL,
+  BENCODE_VALUE,
+  BENCODE_DICT_KEY,
+  BENCODE_DICT_VAL,
+  BENCODE_LIST,
+  BENCODE_STRING_LEN,
+  BENCODE_STRING,
+  BENCODE_NUMBER_SIGN,
+  BENCODE_NUMBER
+};
+} // namespace
+
+BencodeParser::BencodeParser(StructParserStateMachine* psm)
+  : psm_(psm),
+    currentState_(BENCODE_INITIAL),
+    numberSign_(1),
+    number_(0),
+    numConsumed_(0),
+    lastError_(0)
+{
+  stateStack_.push(BENCODE_FINISH);
+}
+
+BencodeParser::~BencodeParser()
+{}
+
+ssize_t BencodeParser::parseUpdate(const char* data, size_t size)
+{
+  size_t i;
+  if(currentState_ == BENCODE_FINISH) {
+    return 0;
+  } else if(currentState_ == BENCODE_ERROR) {
+    return lastError_;
+  }
+  for(i = 0; i < size && currentState_ != BENCODE_FINISH; ++i) {
+    char c = data[i];
+    switch(currentState_) {
+    case BENCODE_LIST:
+      if(c == 'e') {
+        onListEnd();
+        break;
+      } else {
+        int rv = pushState(currentState_);
+        if(rv < 0) {
+          return rv;
+        }
+        currentState_ = BENCODE_VALUE;
+        runBeginCallback(STRUCT_ARRAY_DATA_T);
+      }
+      // Fall through
+    case BENCODE_INITIAL:
+    case BENCODE_VALUE:
+      switch(c) {
+      case 'd': {
+        currentState_ = BENCODE_DICT_KEY;
+        runBeginCallback(STRUCT_DICT_T);
+        break;
+      }
+      case'l':
+        currentState_ = BENCODE_LIST;
+        runBeginCallback(STRUCT_ARRAY_T);
+        break;
+      case 'i':
+        number_ = 0;
+        numberSign_ = 1;
+        numConsumed_ = 0;
+        currentState_ = BENCODE_NUMBER_SIGN;
+        runBeginCallback(STRUCT_NUMBER_T);
+        break;
+      default:
+        if(util::isDigit(c)) {
+          strLength_ = c - '0';
+          numConsumed_ = 1;
+          currentState_ = BENCODE_STRING_LEN;
+          runBeginCallback(STRUCT_STRING_T);
+          break;
+        } else {
+          currentState_ = BENCODE_ERROR;
+          return lastError_ = ERR_UNEXPECTED_CHAR_BEFORE_VAL;
+        }
+      }
+      break;
+    case BENCODE_DICT_KEY: {
+      if(c == 'e') {
+        onDictEnd();
+        break;
+      }
+      int rv = pushState(currentState_);
+      if(rv < 0) {
+        return rv;
+      }
+      runBeginCallback(STRUCT_DICT_KEY_T);
+      // Fall through
+    }
+    case BENCODE_STRING_LEN: {
+      size_t j;
+      for(j = i; j < size && in(data[j], '0', '9'); ++j) {
+        if((INT64_MAX - (data[j] - '0'))/ 10 < strLength_) {
+          currentState_ = BENCODE_ERROR;
+          return lastError_ = ERR_STRING_LENGTH_OUT_OF_RANGE;
+        }
+        strLength_ *= 10;
+        strLength_ += data[j] - '0';
+      }
+      numConsumed_ += j - i;
+      if(j != size) {
+        if(data[j] != ':' || numConsumed_ == 0) {
+          currentState_ = BENCODE_ERROR;
+          return lastError_ = ERR_INVALID_STRING_LENGTH;
+        }
+        i = j;
+        currentState_ = BENCODE_STRING;
+        if(strLength_ == 0) {
+          runCharactersCallback(0, 0);
+          onStringEnd();
+        }
+      } else {
+        i = j - 1;
+      }
+      break;
+    }
+    case BENCODE_STRING: {
+      size_t nread = std::min(static_cast<int64_t>(size - i), strLength_);
+      runCharactersCallback(&data[i], nread);
+      strLength_ -= nread;
+      i += nread - 1;
+      if(strLength_ == 0) {
+        onStringEnd();
+      }
+      break;
+    }
+    case BENCODE_NUMBER_SIGN: {
+      switch(c) {
+      case '+':
+        numberSign_ = 1;
+        currentState_ = BENCODE_NUMBER;
+        break;
+      case '-':
+        numberSign_ = -1;
+        currentState_ = BENCODE_NUMBER;
+        break;
+      default:
+        if(util::isDigit(c)) {
+          number_ = c - '0';
+          numConsumed_ = 1;
+          currentState_ = BENCODE_NUMBER;
+        }
+      }
+      break;
+    }
+    case BENCODE_NUMBER: {
+      size_t j;
+      for(j = i; j < size && in(data[j], '0', '9'); ++j) {
+        if((INT64_MAX - (data[j] - '0'))/ 10 < number_) {
+          currentState_ = BENCODE_ERROR;
+          return lastError_ = ERR_NUMBER_OUT_OF_RANGE;
+        }
+        number_ *= 10;
+        number_ += data[j] - '0';
+      }
+      numConsumed_ += j - i;
+      if(j != size) {
+        if(data[j] != 'e' || numConsumed_ == 0) {
+          currentState_ = BENCODE_ERROR;
+          return lastError_ = ERR_INVALID_NUMBER;
+        }
+        i = j;
+        onNumberEnd();
+      } else {
+        i = j - 1;
+      }
+      break;
+    }
+    }
+  }
+  return i;
+}
+
+ssize_t BencodeParser::parseFinal(const char* data, size_t len)
+{
+  ssize_t rv;
+  rv = parseUpdate(data, len);
+  if(rv >= 0) {
+    if(currentState_ != BENCODE_FINISH &&
+       currentState_ != BENCODE_INITIAL) {
+      rv = ERR_PREMATURE_DATA;
+    }
+  }
+  return rv;
+}
+
+void BencodeParser::reset()
+{
+  psm_->reset();
+  currentState_ = BENCODE_INITIAL;
+  lastError_ = 0;
+  while(!stateStack_.empty()) {
+    stateStack_.pop();
+  }
+  stateStack_.push(BENCODE_FINISH);
+}
+
+void BencodeParser::onStringEnd()
+{
+  runEndCallback(stateTop() == BENCODE_DICT_KEY ?
+                 STRUCT_DICT_KEY_T : STRUCT_STRING_T);
+  onValueEnd();
+}
+
+void BencodeParser::onNumberEnd()
+{
+  runNumberCallback(numberSign_ * number_);
+  runEndCallback(STRUCT_NUMBER_T);
+  onValueEnd();
+}
+
+void BencodeParser::onDictEnd()
+{
+  runEndCallback(STRUCT_DICT_T);
+  onValueEnd();
+}
+
+void BencodeParser::onListEnd()
+{
+  runEndCallback(STRUCT_ARRAY_T);
+  onValueEnd();
+}
+
+void BencodeParser::onValueEnd()
+{
+  switch(stateTop()) {
+  case BENCODE_DICT_KEY:
+    popState();
+    pushState(BENCODE_DICT_VAL);
+    currentState_ = BENCODE_VALUE;
+    runBeginCallback(STRUCT_DICT_DATA_T);
+    break;
+  case BENCODE_DICT_VAL:
+    runEndCallback(STRUCT_DICT_DATA_T);
+    popState();
+    currentState_ = BENCODE_DICT_KEY;
+    break;
+  case BENCODE_LIST:
+    runEndCallback(STRUCT_ARRAY_DATA_T);
+    popState();
+    currentState_ = BENCODE_LIST;
+    break;
+  default:
+    assert(stateTop() == BENCODE_FINISH);
+    currentState_ = stateTop();
+    break;
+  }
+}
+
+int BencodeParser::pushState(int state)
+{
+  if(stateStack_.size() >= 50) {
+    return ERR_STRUCTURE_TOO_DEEP;
+  } else {
+    stateStack_.push(state);
+    return 0;
+  }
+}
+
+int BencodeParser::stateTop() const
+{
+  return stateStack_.top();
+}
+
+int BencodeParser::popState()
+{
+  int state = stateStack_.top();
+  stateStack_.pop();
+  return state;
+}
+
+void BencodeParser::runBeginCallback(int elementType)
+{
+  // switch(elementType) {
+  // case STRUCT_DICT_T:
+  //   std::cout << "object start" << std::endl;
+  //   break;
+  // case STRUCT_DICT_KEY_T:
+  //   std::cout << "object key start" << std::endl;
+  //   break;
+  // case STRUCT_DICT_DATA_T:
+  //   std::cout << "object data start" << std::endl;
+  //   break;
+  // case STRUCT_ARRAY_T:
+  //   std::cout << "array start" << std::endl;
+  //   break;
+  // case STRUCT_ARRAY_DATA_T:
+  //   std::cout << "array data start" << std::endl;
+  //   break;
+  // case STRUCT_STRING_T:
+  //   std::cout << "string start" << std::endl;
+  //   break;
+  // case STRUCT_NUMBER_T:
+  //   std::cout << "number start" << std::endl;
+  //   break;
+  // case STRUCT_BOOL_T:
+  //   std::cout << "bool start" << std::endl;
+  //   break;
+  // case STRUCT_NULL_T:
+  //   std::cout << "null start" << std::endl;
+  //   break;
+  // default:
+  //   break;
+  // };
+  psm_->beginElement(elementType);
+}
+
+void BencodeParser::runEndCallback(int elementType)
+{
+  // switch(elementType) {
+  // case STRUCT_DICT_T:
+  //   std::cout << "object end" << std::endl;
+  //   break;
+  // case STRUCT_DICT_KEY_T:
+  //   std::cout << "object key end" << std::endl;
+  //   break;
+  // case STRUCT_DICT_DATA_T:
+  //   std::cout << "object data end" << std::endl;
+  //   break;
+  // case STRUCT_ARRAY_T:
+  //   std::cout << "array end" << std::endl;
+  //   break;
+  // case STRUCT_ARRAY_DATA_T:
+  //   std::cout << "array data end" << std::endl;
+  //   break;
+  // case STRUCT_STRING_T:
+  //   std::cout << "string end" << std::endl;
+  //   break;
+  // case STRUCT_NUMBER_T:
+  //   std::cout << "number end" << std::endl;
+  //   break;
+  // case STRUCT_BOOL_T:
+  //   std::cout << "bool end" << std::endl;
+  //   break;
+  // case STRUCT_NULL_T:
+  //   std::cout << "null end" << std::endl;
+  //   break;
+  // default:
+  //   break;
+  // };
+  psm_->endElement(elementType);
+}
+
+void BencodeParser::runCharactersCallback(const char* data, size_t len)
+{
+  psm_->charactersCallback(data, len);
+}
+
+void BencodeParser::runNumberCallback(int64_t number)
+{
+  psm_->numberCallback(number, 0, 0);
+}
+
+} // namespace bittorrent
+
+} // namespace aria2
diff --git a/src/BencodeParser.h b/src/BencodeParser.h
new file mode 100644
index 00000000..eb1c4d67
--- /dev/null
+++ b/src/BencodeParser.h
@@ -0,0 +1,104 @@
+/* <!-- 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_BENCODE_PARSER_H
+#define D_BENCODE_PARSER_H
+
+#include "common.h"
+
+#include <stack>
+
+namespace aria2 {
+
+class StructParserStateMachine;
+
+namespace bittorrent {
+
+enum BencodeError {
+  ERR_UNEXPECTED_CHAR_BEFORE_VAL = -1,
+  ERR_INVALID_NUMBER = -2,
+  ERR_NUMBER_OUT_OF_RANGE = -3,
+  ERR_PREMATURE_DATA = -4,
+  ERR_STRUCTURE_TOO_DEEP = -5,
+  ERR_INVALID_STRING_LENGTH = -6,
+  ERR_STRING_LENGTH_OUT_OF_RANGE = -7
+};
+
+class BencodeParser {
+public:
+  BencodeParser(StructParserStateMachine* psm);
+  ~BencodeParser();
+  // 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);
+  // Parses |size| bytes of data |data| and returns the number of
+  // bytes processed. On error, one of the negative error codes is
+  // returned. Call this function to signal the parser that this is
+  // the last piece of data. This function does NOT reset the internal
+  // state.
+  ssize_t parseFinal(const char* data, size_t size);
+  // Resets the internal state of the parser and makes it ready for
+  // reuse.
+  void reset();
+private:
+  int pushState(int state);
+  int stateTop() const;
+  int popState();
+  void runBeginCallback(int elementType);
+  void runEndCallback(int elementType);
+  void runCharactersCallback(const char* data, size_t len);
+  void runNumberCallback(int64_t number);
+
+  void onStringEnd();
+  void onNumberEnd();
+  void onDictEnd();
+  void onListEnd();
+  void onValueEnd();
+
+  StructParserStateMachine* psm_;
+  std::stack<int> stateStack_;
+  int currentState_;
+  int64_t strLength_;
+  int numberSign_;
+  int64_t number_;
+  size_t numConsumed_;
+  int lastError_;
+};
+
+} // namespace bittorrent
+
+} // namespace aria2
+
+#endif // D_BENCODE_PARSER_H
diff --git a/src/Makefile.am b/src/Makefile.am
index b56090c2..25ec3723 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -508,7 +508,9 @@ SRCS += PeerAbstractCommand.cc PeerAbstractCommand.h\
 	LpdMessage.cc LpdMessage.h\
 	LpdReceiveMessageCommand.cc LpdReceiveMessageCommand.h\
 	LpdDispatchMessageCommand.cc LpdDispatchMessageCommand.h\
-	bencode2.cc bencode2.h
+	bencode2.cc bencode2.h\
+	BencodeParser.cc BencodeParser.h\
+	ValueBaseBencodeParser.h
 endif # ENABLE_BITTORRENT
 
 if ENABLE_METALINK
diff --git a/src/ValueBaseBencodeParser.h b/src/ValueBaseBencodeParser.h
new file mode 100644
index 00000000..ffa109e4
--- /dev/null
+++ b/src/ValueBaseBencodeParser.h
@@ -0,0 +1,53 @@
+/* <!-- 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_VALUE_BASE_BENCODE_PARSER_H
+#define D_VALUE_BASE_BENCODE_PARSER_H
+
+#include "GenericParser.h"
+#include "BencodeParser.h"
+#include "ValueBaseStructParserStateMachine.h"
+
+namespace aria2 {
+
+namespace bittorrent {
+
+typedef GenericParser<BencodeParser, ValueBaseStructParserStateMachine>
+ValueBaseBencodeParser;
+
+} // namespace bittorrent
+
+} // namespace aria2
+
+#endif // D_VALUE_BASE_BENCODE_PARSER_H