btcontent.cpp

cTorrent advanced 3.3.2。是对 CTorrent 的一个改进版本。这是目前的最新版。

#include "btcontent.h"

#ifdef WINDOWS
#include <direct.h>
#include <io.h>
#include <memory.h>
// include windows sha1 header here.

#else
#include <unistd.h>
#include <sys/param.h>

#if defined(USE_STANDALONE_SHA1)
#include "sha1.h"
#elif defined(HAVE_OPENSSL_SHA_H)
#include <openssl/sha.h>
#elif defined(HAVE_SSL_SHA_H)
#include <ssl/sha.h>
#elif defined(HAVE_SHA_H)
#include <sha.h>
#endif

#endif

#include <stdio.h>
#include <sys/stat.h>
#include <stdlib.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <ctype.h>

#include "btconfig.h"
#include "bencode.h"
#include "peer.h"
#include "httpencode.h"
#include "tracker.h"
#include "peerlist.h"
#include "ctcs.h"
#include "console.h"
#include "bttime.h"

#ifndef HAVE_RANDOM
#include "compat.h"
#endif

#define meta_str(keylist,pstr,pint) decode_query(b,flen,(keylist),(pstr),(pint),(int64_t*) 0,QUERY_STR)
#define meta_int(keylist,pint) decode_query(b,flen,(keylist),(const char**) 0,(pint),(int64_t*) 0,QUERY_INT)
#define meta_pos(keylist) decode_query(b,flen,(keylist),(const char**) 0,(size_t*) 0,(int64_t*) 0,QUERY_POS)

// Does "ca" overlap the data that lies from roff to rlen?
#define CACHE_FIT(ca,roff,rlen)	\
(max_uint64_t((ca)->bc_off,(roff)) <= \
 min_uint64_t(((ca)->bc_off + (ca)->bc_len - 1),(roff + rlen - 1)))


btContent BTCONTENT;

static void Sha1(char *ptr,size_t len,unsigned char *dm)
{
#if defined(USE_STANDALONE_SHA1)
  SHA1_CTX context;
  SHA1Init(&context);
  SHA1Update(&context,(unsigned char*)ptr,len);
  SHA1Final(dm,&context);
#else
#ifdef WINDOWS
  ;
#else
  SHA_CTX context;
  SHA1_Init(&context);
  SHA1_Update(&context,(unsigned char*)ptr,len);
  SHA1_Final(dm,&context);
#endif
#endif
}

btContent::btContent()
{
  m_announce = global_piece_buffer = (char*) 0;
  global_buffer_size = 0;
  memset(m_announcelist, 0, 9*sizeof(char *));
  m_hash_table = (unsigned char *) 0;
  m_create_date = m_seed_timestamp = (time_t) 0;
  m_private = 0;
  m_comment = m_created_by = (char *)0;

  pBF = (BitField*) 0;
  pBMasterFilter = (BitField*) 0;
  pBRefer = (BitField*) 0;
  pBChecked = (BitField*) 0;
  pBMultPeer = (BitField*) 0;
  time(&m_start_timestamp);
  m_cache_oldest = m_cache_newest = (BTCACHE *)0;
  m_cache_size = m_cache_used = 0;
  m_flush_failed = m_flush_tried = (time_t) 0;
  m_check_piece = 0;
  m_flushq = (BTFLUSH *)0;
  m_filters = m_current_filter = (BFNODE *)0;
  m_prevdlrate = 0;
}

int btContent::CreateMetainfoFile(const char *mifn)
{
  FILE *fp;
  fp = fopen(mifn, "r");
  if( fp ){
    CONSOLE.Warning(1, "error, file \"%s\" already exists.", mifn);
    return -1;
  }else if( ENOENT != errno ){
    CONSOLE.Warning(1, "error, couldn't create \"%s\".", mifn);
    return -1;
  }

  fp = fopen(mifn, "w");

  if( !fp ){
    CONSOLE.Warning(1, "error, open \"%s\" failed:  %s", mifn, strerror(errno));
    return -1;
  }
  if( bencode_begin_dict(fp) != 1 ) goto err;

  // Entries in dictionary must be sorted by key!

  // announce
  if( bencode_str("announce", fp) != 1 ) goto err;
  if( bencode_str(m_announce, fp) != 1 ) goto err;

  // comment
  if( arg_comment ){
    if( bencode_str("comment", fp) != 1 ) goto err;
    if( bencode_str(arg_comment, fp) != 1 ) goto err;
  }

  // created by
  if( bencode_str("created by", fp) != 1 ) goto err;
  if( bencode_str(cfg_user_agent, fp) != 1 ) goto err;

  // creation date
  if( bencode_str("creation date", fp) != 1 ) goto err;
  if( bencode_int(m_create_date, fp) != 1 ) goto err;

  // info dict
  if( bencode_str("info", fp) != 1 ) goto err;
  if( bencode_begin_dict(fp) != 1 ) goto err;

  { // Entries in dictionary must be sorted by key!
    // files & name, or length & name
    if( m_btfiles.FillMetaInfo(fp) != 1 ) goto err;

    // piece length
    if( bencode_str("piece length", fp) != 1 ) goto err;
    if( bencode_int(m_piece_length, fp) != 1 ) goto err;

    // pieces (hash table)
    if( bencode_str("pieces", fp) != 1 ) goto err;
    if( bencode_buf((const char*) m_hash_table, m_hashtable_length, fp) != 1 )
      goto err;

    // private
    if( arg_flg_private ){
      if( bencode_str("private", fp) != 1 ) goto err;
      if( bencode_int(1, fp) != 1 ) goto err;
    }

    if( bencode_end_dict_list(fp) != 1 ) goto err;  // end info
  }

  if( bencode_end_dict_list(fp) != 1 ) goto err;  // end torrent

  fclose(fp);
  return 0;
 err:
  if( fp ) fclose(fp);
  return -1;
}

int btContent::InitialFromFS(const char *pathname, char *ann_url, size_t piece_length)
{
  size_t n, percent;

  // piece length
  m_piece_length = piece_length;
  if( m_piece_length % 65536 ){ 
    m_piece_length /= 65536;
    m_piece_length *= 65536;
  }

  // This is really just a sanity check on the piece length to create.
  if( !m_piece_length || m_piece_length > 4096*1024 )
    m_piece_length = 262144;
  
  m_announce = ann_url;
  m_create_date = time((time_t*) 0);

  if(m_btfiles.BuildFromFS(pathname) < 0) return -1;

  global_piece_buffer = new char[m_piece_length];
#ifndef WINDOWS
  if( !global_piece_buffer ) return -1;
#endif
  global_buffer_size = m_piece_length;
  
  // n pieces
  m_npieces = m_btfiles.GetTotalLength() / m_piece_length;
  if( m_btfiles.GetTotalLength() % m_piece_length ) m_npieces++;

  // create hash table.
  m_hashtable_length = m_npieces * 20;
  m_hash_table = new unsigned char[m_hashtable_length];
#ifndef WINDOWS
  if( !m_hash_table ) return -1;
#endif

  percent = m_npieces / 100;
  if( !percent ) percent = 1;

  CONSOLE.Interact_n("");
  for( n = 0; n < m_npieces; n++ ){
    if( GetHashValue(n, m_hash_table + n * 20) < 0 ) return -1;
    if( n % percent == 0 || n == m_npieces-1 ){
      CONSOLE.InteractU("Create hash table: %d/%d", (int)n+1, (int)m_npieces);
    }
  }
  return 0;
}

int btContent::PrintOut()
{
  CONSOLE.Print("META INFO");
  CONSOLE.Print("Announce: %s", m_announce);
  if( m_announcelist[0] ){
    CONSOLE.Print("Alternates:");
    for( int n=0; n < 9 && m_announcelist[n]; n++ )
      CONSOLE.Print(" %d. %s", n+1, m_announcelist[n]);
  }
  if( m_create_date ){
    char s[42];
#ifdef HAVE_CTIME_R_3
    ctime_r(&m_create_date, s, sizeof(s));
#else
    ctime_r(&m_create_date, s);
#endif
    if( s[strlen(s)-1] == '\n' ) s[strlen(s)-1] = '\0';
    CONSOLE.Print("Created On: %s", s);
  }
  CONSOLE.Print("Piece length: %lu", (unsigned long)m_piece_length);
  if( m_private ) CONSOLE.Print("Private: %s", m_private ? "Yes" : "No");
  if( m_comment ){
    char *s = new char[strlen(m_comment)+1];
    if(s){
      strcpy(s, m_comment);
      for(char *t=s; *t; t++)
        if( !isprint(*t) && !strchr("\t\r\n", *t) ) *t = '?';
      CONSOLE.Print("Comment: %s", s);
      delete []s;
    }
  }
  if( m_created_by ) CONSOLE.Print("Created with: %s", m_created_by);
  m_btfiles.PrintOut();
  return 0;
}

int btContent::PrintFiles()
{
  m_btfiles.PrintOut();
  return 0;
}

int btContent::InitialFromMI(const char *metainfo_fname,const char *saveas)
{
#define ERR_RETURN()	{if(b) delete []b; return -1;}
  unsigned char *ptr = m_shake_buffer;
  char *b;
  const char *s;
  size_t flen, q, r;
  int tmp;

  m_cache_hit = m_cache_miss = m_cache_pre = 0;
  time(&m_cache_eval_time);

  b = _file2mem(metainfo_fname,&flen);
  if ( !b ) return -1;

  // announce
  if( !meta_str("announce",&s,&r) ) ERR_RETURN();
  if( r > MAXPATHLEN ) ERR_RETURN();
  m_announce = new char [r + 1];
  memcpy(m_announce, s, r);
  m_announce[r] = '\0';

  // announce-list
  if( r = meta_pos("announce-list") ){
    const char *sptr;
    size_t slen, n=0;
    if( q = decode_list(b+r, flen-r, (char *)0) ){
      int alend = r + q;
      r++;  // 'l'
      for( ; r < alend && *(b+r) != 'e' && n < 9; ){  // each list
        if( !(q = decode_list(b+r, alend-r, (char *)0)) ) break;
        r++;  // 'l'
        for( ; r < alend && n < 9; ){  // each value
          if( !(q = buf_str(b+r, alend-r, &sptr, &slen)) )
            break;  // next list
          r += q;
          if( strncasecmp(m_announce, sptr, slen) ){
            m_announcelist[n] = new char[slen+1];
            memcpy(m_announcelist[n], sptr, slen);
            (m_announcelist[n])[slen] = '\0';
            n++;
          }
        }
        r++;  // 'e'
      }
    }
  }
  
  if( meta_int("creation date", &r) ) m_create_date = (time_t) r;
  if( meta_str("comment", &s, &r) && r ){
    if( m_comment = new char[r + 1] ){
      memcpy(m_comment, s, r);
      m_comment[r] = '\0';
    }
  }
  if( meta_str("created by", &s, &r) && r ){
    if( m_created_by = new char[r + 1] ){
      memcpy(m_created_by, s, r);
      m_created_by[r] = '\0';
    }
  }

  // infohash
  if( !(r = meta_pos("info")) ) ERR_RETURN();
  if( !(q = decode_dict(b + r, flen - r, (char *) 0)) ) ERR_RETURN();
  Sha1(b + r, q, m_shake_buffer + 28);

  // private flag
  if( meta_int("info|private", &r) ) m_private = r;
 
  // hash table
  if( !meta_str("info|pieces",&s,&m_hashtable_length) ||
      m_hashtable_length % 20 != 0 ) ERR_RETURN();

  if( !arg_flg_exam_only ){
    m_hash_table = new unsigned char[m_hashtable_length];
#ifndef WINDOWS
    if( !m_hash_table ) ERR_RETURN();
#endif
    memcpy(m_hash_table, s, m_hashtable_length);
  }

  if( !meta_int("info|piece length",&m_piece_length) ) ERR_RETURN();
  m_npieces = m_hashtable_length / 20;

  if( m_piece_length < cfg_req_slice_size )
    cfg_req_slice_size = m_piece_length;

  cfg_req_queue_length = (m_piece_length / cfg_req_slice_size) * 2 - 1;

  if( m_btfiles.BuildFromMI(b, flen, saveas) < 0 ) ERR_RETURN();

  delete []b;
  b = (char *)0;
  
  if( arg_flg_exam_only ){
    PrintOut();
    return 0;
  }else{
    arg_flg_exam_only = 1;
    PrintOut();
    arg_flg_exam_only = 0;
  }

  if( (tmp = m_btfiles.CreateFiles()) < 0 ) ERR_RETURN();
  r = tmp;

  if( !arg_flg_exam_only ){
    global_piece_buffer = new char[DEFAULT_SLICE_SIZE];
#ifndef WINDOWS
    if( !global_piece_buffer ) ERR_RETURN();
#endif
    global_buffer_size = DEFAULT_SLICE_SIZE;

    pBF = new BitField(m_npieces);
#ifndef WINDOWS
    if( !pBF ) ERR_RETURN();
#endif

    pBRefer = new BitField(m_npieces);
#ifndef WINDOWS
    if( !pBRefer ) ERR_RETURN();
#endif

    pBChecked = new BitField(m_npieces);
#ifndef WINDOWS
    if( !pBChecked ) ERR_RETURN();
#endif

    pBMultPeer = new BitField(m_npieces);
#ifndef WINDOWS
    if( !pBMultPeer ) ERR_RETURN();
#endif

    //create the file filter
    pBMasterFilter = new BitField(m_npieces);
#ifndef WINDOWS