recovery.c

open arj source

 single_pad_r=malloc_msg(DEFAULT_PROTPAD_SIZE+2);
 protpad_bck=malloc_msg(protpad_size+2);
 astream=file_open_noarch(name, m_rb);
 if(file_exists(protname))
 {
  xstream=file_open_noarch(protname, m_rb);
  rd_offset=0L;
 }
 else
 {
  xstream=astream;
  rd_offset=chk_prot_sig(xstream, sig_offset);
  if(rd_offset==0L)
  {
   if(test_mode)
   {
    msg_cprintf(0, M_NO_PROT_DATA);
    nputlf();
    return(0);
   }
   else
    error(M_NO_PROT_DATA);
  }
 }
 fseek(astream, 0L, SEEK_END);
 ifile_size=ftell(astream);
 if(rd_offset!=0L)
  ifile_size=rd_offset-6L;
 fseek(xstream, rd_offset, SEEK_SET);
 fread(single_pad, 1, DEFAULT_PROTPAD_SIZE, xstream);
 crc32term=CRC_MASK;
 crc32_for_block(single_pad+4, DEFAULT_PROTPAD_SIZE-4);
 /* Possible XRJ damage */
 if(mget_dword(&single_pad[0])!=crc32term||
    mget_word (&single_pad[4])!=0x1111)
 {
  fseek(xstream, (long)DEFAULT_PROTPAD_SIZE*3+rd_offset, SEEK_SET);
  fread(single_pad, 1, DEFAULT_PROTPAD_SIZE, xstream);
  crc32term=CRC_MASK;
  crc32_for_block(single_pad+4, DEFAULT_PROTPAD_SIZE-4);
  if(mget_dword(&single_pad[0])!=crc32term||
     mget_word (&single_pad[4])!=0x1111)
   error(M_RECOVERY_CRC_DAMAGED);
 }
 fseek(xstream, rd_offset, SEEK_SET);
 total_blocks=mget_word(&single_pad[6]);
 orig_ifile_size=mget_dword(&single_pad[10]);
 if(ifile_size==orig_ifile_size)
 {
  fseek(astream, 0L, SEEK_SET);
  msg_cprintf(0, M_WORKING);
  for(cur_stream=0; cur_stream<total_blocks; cur_stream++)
  {
   msg_cprintf(0, (FMSG *)prot_ticker);
   ins_lf=1;
   damage_level=0;
   fseek(xstream, (unsigned long)DEFAULT_PROTPAD_SIZE*
                  (unsigned long)cur_stream+rd_offset, SEEK_SET);
   fread(single_pad, 1, DEFAULT_PROTPAD_SIZE, xstream);
   crc32term=CRC_MASK;
   crc32_for_block(single_pad+4, DEFAULT_PROTPAD_SIZE-4);
   if (mget_dword(&single_pad[0])!=crc32term)
   damage_level=2;
   fseek(xstream, (unsigned long)DEFAULT_PROTPAD_SIZE*
                  (unsigned long)cur_stream+
                  3L*(unsigned long)DEFAULT_PROTPAD_SIZE*
                  (unsigned long)total_blocks+rd_offset, SEEK_SET);
   fread(single_pad_r, 1, DEFAULT_PROTPAD_SIZE, xstream);
   crc32term=CRC_MASK;
   crc32_for_block(single_pad_r+4, DEFAULT_PROTPAD_SIZE-4);
   if(mget_dword(&single_pad_r[0])!=crc32term)
   {
    if(damage_level==2)
    {
     if(ins_lf)
     {
      nputlf();
      ins_lf=0;
     }
     msg_cprintf(0, M_RECOVERY_2CRC_DAMAGED);
     abort_recovery();
    }
    damage_level=1;
   }
   for(pad_ctr=0; pad_ctr<DEFAULT_PROTPAD_SIZE-14; pad_ctr++)
   {
    single_pad[pad_ctr]=single_pad[pad_ctr+14];
    single_pad_r[pad_ctr]=single_pad_r[pad_ctr+14];
   }
   fseek(xstream, (unsigned long)DEFAULT_PROTPAD_SIZE*
         (unsigned long)cur_stream+(unsigned long)DEFAULT_PROTPAD_SIZE*
         (unsigned long)total_blocks+rd_offset, SEEK_SET);
   fread(protpad, 1, DEFAULT_PROTPAD_SIZE, xstream);
   crc32term=CRC_MASK;
   crc32_for_block(protpad+4, DEFAULT_PROTPAD_SIZE-4);
   damage_flag=(mget_dword(&protpad[0])!=crc32term)?1:0;
   if(!damage_flag)
   {
    for(pad_ctr=0; pad_ctr<DEFAULT_PROTPAD_SIZE-4; pad_ctr++)
     protpad[pad_ctr]=protpad[pad_ctr+4];
    for(pad_ctr=0; pad_ctr<pad1_size; pad_ctr++)
    {
     if(damage_level==2)
      protpad[pad_ctr+protpad_size-pad1_size]=single_pad_r[pad_ctr];
     else
      protpad[pad_ctr+protpad_size-pad1_size]=single_pad[pad_ctr];
    }
   }
   fseek(xstream, (unsigned long)DEFAULT_PROTPAD_SIZE*
                  (unsigned long)cur_stream+2L*
                  (unsigned long)DEFAULT_PROTPAD_SIZE*
                  (unsigned long)total_blocks+rd_offset, SEEK_SET);
   fread(protpad_r, 1, DEFAULT_PROTPAD_SIZE, xstream);
   crc32term=CRC_MASK;
   crc32_for_block(protpad_r+4, DEFAULT_PROTPAD_SIZE-4);
   pad_damage_flag=(mget_dword(&protpad_r[0])!=crc32term)?1:0;
   if(!pad_damage_flag)
   {
    for(pad_ctr=0; pad_ctr<DEFAULT_PROTPAD_SIZE-4; pad_ctr++)
     protpad_r[pad_ctr]=protpad_r[pad_ctr+4];
    for(pad_ctr=0; pad_ctr<pad1_size; pad_ctr++)
    {
     if(damage_level==2)
      protpad_r[pad_ctr+protpad_size-pad1_size]=
       single_pad_r[pad1_size+pad_ctr];
     else
      protpad_r[pad_ctr+protpad_size-pad1_size]=
       single_pad[pad1_size+pad_ctr];
    }
   }
   cur_section=0;
   block_offset=(unsigned long)cur_stream*(unsigned long)DEFAULT_PROTPAD_SIZE;
   while(block_offset<ifile_size)
   {
    fseek(astream, block_offset, SEEK_SET);
    section_size=(int)min((unsigned long)DEFAULT_PROTPAD_SIZE,
                          (ifile_size-block_offset));
    section_size=fread(protpad_bck+1, 1, section_size, astream);
    protpad_bck[0]='\0';
    for(pad_ctr=section_size+1; pad_ctr<protpad_size; pad_ctr++)
     protpad_bck[pad_ctr]='\0';
    crc32term=(unsigned long)
              crc16_for_block(protpad_bck+1, DEFAULT_PROTPAD_SIZE);
    crc32_for_block(protpad_bck+1, DEFAULT_PROTPAD_SIZE);
    if(damage_level==0||damage_level==1)
    {
     if(mget_word(&single_pad[(pad1_size<<1)+((cur_section<<2)>>1)])!=
        (unsigned short)(crc32term%65536L))
      goto recovery;
    }
    if(damage_level==0||damage_level==2)
    {
     if(mget_word     
        (&single_pad_r[(pad1_size<<1)+((cur_section<<2)>>1)])!=
        (unsigned short)(crc32term>>16))
      goto recovery;
    }
    block_offset+=(unsigned long)
                  DEFAULT_PROTPAD_SIZE*(unsigned long)total_blocks;
    cur_section++;
   }
  }
  if(test_mode==2)
   goto recovery;
 }
 else
 {
recovery:
  nputlf();
  if(test_mode!=1)
  {
   atstream=ostream=file_open_noarch(rec_name, m_wbp);
   fseek(astream, 0L, SEEK_SET);
   errors=0;
   for(dest_file_size=min(ifile_size, orig_ifile_size);
       dest_file_size>0;
       dest_file_size-=(unsigned long)section_size)
   {
    section_size=min(DEFAULT_PROTPAD_SIZE, dest_file_size);
    if(fread(single_pad, 1, section_size, astream)!=section_size)
     break;
    if(fwrite(single_pad, 1, section_size, ostream)!=section_size)
     break;
   }
   for(dest_file_size=
       (ifile_size>=orig_ifile_size)?0:orig_ifile_size-ifile_size;
       dest_file_size>0;
       dest_file_size-=(unsigned long)section_size)
   {
    section_size=min(DEFAULT_PROTPAD_SIZE, dest_file_size);
    if(fwrite(single_pad, 1, section_size, ostream)!=section_size)
     break;
   }
   fseek(ostream, 0L, SEEK_END);
   if(ftell(ostream)!=orig_ifile_size)
    error(M_DISK_FULL);
   ifile_size=orig_ifile_size;
   for(cur_stream=0; cur_stream<total_blocks; cur_stream++)
   {
    msg_cprintf(0, (FMSG *)prot_ticker);
    ins_lf=1;
    damage_level=0;
    fseek(xstream,
          (unsigned long)DEFAULT_PROTPAD_SIZE*(unsigned long)cur_stream+
          rd_offset, SEEK_SET);
    fread(single_pad, 1, DEFAULT_PROTPAD_SIZE, xstream);
    crc32term=CRC_MASK;
    crc32_for_block(single_pad+4, DEFAULT_PROTPAD_SIZE-4);
    if(mget_dword(&single_pad[0])!=crc32term)
     damage_level=2;
    fseek(xstream, (unsigned long)DEFAULT_PROTPAD_SIZE*
          (unsigned long)cur_stream+3L*(unsigned long)DEFAULT_PROTPAD_SIZE*
          (unsigned long)total_blocks+rd_offset, SEEK_SET);
    fread(single_pad_r, 1, DEFAULT_PROTPAD_SIZE, xstream);
    crc32term=CRC_MASK;
    crc32_for_block(single_pad_r+4, DEFAULT_PROTPAD_SIZE-4);
    if(mget_dword(&single_pad_r[0])!=crc32term)
    {
     if(damage_level==2)
     {
      if(ins_lf)
      {
       nputlf();
       ins_lf=0;
      }
      msg_cprintf(0, M_RECOVERY_2CRC_DAMAGED);
      abort_recovery();
     }
     damage_level=1;
    }
    for(pad_ctr=0; pad_ctr<DEFAULT_PROTPAD_SIZE-14; pad_ctr++)
    {
     single_pad[pad_ctr]=single_pad[pad_ctr+14];
     single_pad_r[pad_ctr]=single_pad_r[pad_ctr+14];
    }
    fseek(xstream, (unsigned long)DEFAULT_PROTPAD_SIZE*
          (unsigned long)cur_stream+(unsigned long)DEFAULT_PROTPAD_SIZE*
          (unsigned long)total_blocks+rd_offset, SEEK_SET);
    fread(protpad, 1, DEFAULT_PROTPAD_SIZE, xstream);
    crc32term=CRC_MASK;
    crc32_for_block(protpad+4, DEFAULT_PROTPAD_SIZE-4);
    damage_flag=(mget_dword(&protpad[0])!=crc32term)?1:0;
    if(!damage_flag)
    {
     for(pad_ctr=0; pad_ctr<DEFAULT_PROTPAD_SIZE-4; pad_ctr++)
      protpad[pad_ctr]=protpad[pad_ctr+4];
     for(pad_ctr=0; pad_ctr<pad1_size; pad_ctr++)
     {
      if(damage_level==2)
       protpad[pad_ctr+protpad_size-pad1_size]=single_pad_r[pad_ctr];
      else
       protpad[pad_ctr+protpad_size-pad1_size]=single_pad[pad_ctr];
     }
    }
    fseek(xstream, (unsigned long)DEFAULT_PROTPAD_SIZE*
                   (unsigned long)cur_stream+2L*
                   (unsigned long)DEFAULT_PROTPAD_SIZE*
                   (unsigned long)total_blocks+rd_offset, SEEK_SET);
    fread(protpad_r, 1, DEFAULT_PROTPAD_SIZE, xstream);
    crc32term=CRC_MASK;
    crc32_for_block(protpad_r+4, DEFAULT_PROTPAD_SIZE-4);
    pad_damage_flag=(mget_dword(&protpad_r[0])!=crc32term)?1:0;
    if(!pad_damage_flag)
    {
     for(pad_ctr=0; pad_ctr<DEFAULT_PROTPAD_SIZE-4; pad_ctr++)
      protpad_r[pad_ctr]=protpad_r[pad_ctr+4];
     for(pad_ctr=0; pad_ctr<pad1_size; pad_ctr++)
     {
      if(damage_level==2)
       protpad_r[pad_ctr+protpad_size-pad1_size]=
        single_pad_r[pad1_size+pad_ctr];
      else
       protpad_r[pad_ctr+protpad_size-pad1_size]=
        single_pad[pad1_size+pad_ctr];
     }
    }
    cur_section=0;
    bck_pad_flag=pad_flag=-1;
    block_offset=(unsigned long)cur_stream*(unsigned long)DEFAULT_PROTPAD_SIZE;
    while(block_offset<ifile_size)
    {
     fseek(ostream, block_offset, SEEK_SET);
     section_size=fread(protpad_bck+1, 1, DEFAULT_PROTPAD_SIZE, ostream);
     protpad_bck[0]='\0';
     for(pad_ctr=section_size+1; pad_ctr<protpad_size; pad_ctr++)
      protpad_bck[pad_ctr]='\0';
     data_damage=0;
     crc32term=(unsigned long)
               crc16_for_block(protpad_bck+1, DEFAULT_PROTPAD_SIZE);
     crc32_for_block(protpad_bck+1, DEFAULT_PROTPAD_SIZE);
     if(damage_level==0||damage_level==1)
     {
      if (mget_word
          (&single_pad[(pad1_size<<1)+((cur_section<<2)>>1)])!=
          (unsigned short)(crc32term%65536L))
       data_damage=1;
     }
     if(damage_level==0||damage_level==2)
     {
      if (mget_word
         (&single_pad_r[(pad1_size<<1)+((cur_section<<2)>>1)])!=
         (unsigned short)(crc32term>>16))
       data_damage=1;
     }
     if(data_damage)
     {
      errors++;
      if(ins_lf)
      {
       nputlf();
       ins_lf=0;
      }
      msg_cprintf(0, M_SECTION_DAMAGED, cur_stream, cur_section);
      if(bck_pad_flag==-1)
      {
       bck_pad_flag=cur_section;
       rec_size=section_size;
      }
      else if(pad_flag==-1)
      {
       pad_flag=cur_section;
       bck_rec_size=section_size;
      }
      else
       abort_recovery();
     }
     else
     {
      for(pad_ctr=0; pad_ctr<protpad_size; pad_ctr++)
      {
       protpad[pad_ctr]^=protpad_bck[pad_ctr];
       protpad_r[pad_ctr]^=protpad_bck[(pad_ctr+cur_section)%protpad_size];
      }
     }
     block_offset+=(unsigned long)DEFAULT_PROTPAD_SIZE*
                   (unsigned long)total_blocks;
     cur_section++;
    }
    if(bck_pad_flag!=-1)
    {
     if(damage_flag!=0&&pad_damage_flag!=0&&bck_pad_flag!=-1)
      abort_recovery();
     else
     {
      if(damage_flag==0&&pad_damage_flag==0)
      {
       if(pad_flag==-1)