recovery.c

open arj source

       {
        fseek(ostream, (unsigned long)DEFAULT_PROTPAD_SIZE*
                       (unsigned long)cur_stream+
                       (unsigned long)bck_pad_flag*
                       (unsigned long)DEFAULT_PROTPAD_SIZE*
                       (unsigned long)total_blocks, SEEK_SET);
        fwrite(protpad+1, 1, rec_size, ostream);
        if(ins_lf)
        {
         nputlf();
         ins_lf=0;
        }
        msg_cprintf(0, M_SECTION_RECOVERED, cur_stream);
       }
       else
       {
        protpad_bck[0]='\0';
        cur_section=0;
        for(pad_ctr=1; pad_ctr<protpad_size; pad_ctr++)
        {
         protpad_bck[(cur_section+pad_flag-bck_pad_flag)%protpad_size]=
          protpad_bck[cur_section]^protpad[cur_section]^
          protpad_r[(cur_section+protpad_size-bck_pad_flag)%protpad_size];
         cur_section=(cur_section+pad_flag-bck_pad_flag)%protpad_size;
        }
        fseek(ostream, (unsigned long)DEFAULT_PROTPAD_SIZE*
                       (unsigned long)cur_stream+
                       (unsigned long)pad_flag*
                       (unsigned long)DEFAULT_PROTPAD_SIZE*
                       (unsigned long)total_blocks, SEEK_SET);
        fwrite(protpad_bck+1, 1, bck_rec_size, ostream);
        if(ins_lf)
        {
         nputlf();
         ins_lf=0;
        }
        msg_cprintf(0, M_SECTION_RECOVERED, cur_stream);
        for(pad_ctr=1; pad_ctr<protpad_size; pad_ctr++)
         protpad_bck[pad_ctr]^=protpad[pad_ctr];
        fseek(ostream, (unsigned long)DEFAULT_PROTPAD_SIZE*
                       (unsigned long)cur_stream+
                       (unsigned long)bck_pad_flag*
                       (unsigned long)DEFAULT_PROTPAD_SIZE*
                       (unsigned long)total_blocks, SEEK_SET);
        fwrite(protpad_bck+1, 1, rec_size, ostream);
        if(ins_lf)
        {
         nputlf();
         ins_lf=0;
        }
        msg_cprintf(0, M_SECTION_RECOVERED, cur_stream);
       }
      }
      else
      {
       if(pad_damage_flag!=0)
       {
        if(pad_flag!=-1)
         abort_recovery();
        fseek(ostream, (unsigned long)DEFAULT_PROTPAD_SIZE*
                       (unsigned long)cur_stream+
                       (unsigned long)bck_pad_flag*
                       (unsigned long)DEFAULT_PROTPAD_SIZE*
                       (unsigned long)total_blocks, SEEK_SET);
        fwrite(protpad+1, 1, rec_size, ostream);
        if(ins_lf)
        {
         nputlf();
         ins_lf=0;
        }
        msg_cprintf(0, M_SECTION_RECOVERED, cur_stream);
       }
       else
       {
        if(damage_flag!=0)
        {
         if(pad_flag!=-1)
          abort_recovery();
         for(pad_ctr=1; pad_ctr<protpad_size; pad_ctr++)
          protpad_bck[pad_ctr]=
           protpad_r[(pad_ctr+protpad_size-bck_pad_flag)%protpad_size];
         fseek(ostream,
               (unsigned long)DEFAULT_PROTPAD_SIZE*
               (unsigned long)cur_stream+
               (unsigned long)bck_pad_flag*
               (unsigned long)DEFAULT_PROTPAD_SIZE*
               (unsigned long)total_blocks, SEEK_SET);
         fwrite(protpad_bck+1, 1, rec_size, ostream);
         if(ins_lf)
         {
          nputlf();
          ins_lf=0;
         }
         msg_cprintf(0, M_SECTION_RECOVERED, cur_stream);
        }
       }
      }
     }
    }
   }
   if(rd_offset!=0L)
    create_protfile(ostream, total_blocks, 1);
   fclose(ostream);
   atstream=NULL;
  }
  else
  {
   fseek(astream, 0L, SEEK_SET);
   errors=0;
   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(astream, block_offset, SEEK_SET);
     section_size=fread(protpad_bck+1, 1, DEFAULT_PROTPAD_SIZE, astream);
     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)
       {
        if(ins_lf)
        {
         nputlf();
         ins_lf=0;
        }
        msg_cprintf(0, M_SECTION_RECOVERED, cur_stream);
       }
       else
       {
        protpad_bck[0]='\0';
        cur_section=0;
        for(pad_ctr=1; pad_ctr<protpad_size; pad_ctr++)
        {
         protpad_bck[(cur_section+pad_flag-bck_pad_flag)%protpad_size]=
          protpad_bck[cur_section]^protpad[cur_section]^
          protpad_r[(cur_section+protpad_size-bck_pad_flag)%protpad_size];
         cur_section=(cur_section+pad_flag-bck_pad_flag)%protpad_size;
        }
        if(ins_lf)
        {
         nputlf();
         ins_lf=0;
        }
        msg_cprintf(0, M_SECTION_RECOVERED, cur_stream);
        for(pad_ctr=1; pad_ctr<protpad_size; pad_ctr++)
         protpad_bck[pad_ctr]^=protpad[pad_ctr];
        if(ins_lf)
        {
         nputlf();
         ins_lf=0;
        }
        msg_cprintf(0, M_SECTION_RECOVERED, cur_stream);
       }
      }
      else
      {
       if(pad_damage_flag!=0)
       {
        if(pad_flag!=-1)
         abort_recovery();
        if(ins_lf)
        {
         nputlf();
         ins_lf=0;
        }
        msg_cprintf(0, M_SECTION_RECOVERED, cur_stream);
       }
       else
       {
        if(damage_flag!=0)
        {
         if(pad_flag!=-1)
          abort_recovery();
         for(pad_ctr=1; pad_ctr<protpad_size; pad_ctr++)
          protpad_bck[pad_ctr]=
           protpad_r[(pad_ctr+protpad_size-bck_pad_flag)%protpad_size];
         if(ins_lf)
         {
          nputlf();
          ins_lf=0;
         }
         msg_cprintf(0, M_SECTION_RECOVERED, cur_stream);
        }
       }
      }
     }
    }
   }
  }
 }
 if(ins_lf)
  nputlf();
 if(rd_offset==0L)
  fclose(xstream);
 fclose(astream);
 free(protpad);
 free(protpad_r);
 free(single_pad);
 free(single_pad_r);
 free(protpad_bck);
 return(errors?0:1);
}