lexmark-blog1-5.cpp

unsigned int __fastcall pjl_ldwelcomescreen_internal3(
        int was_last_write_success,
        int (__fastcall *pjl_getc)(unsigned __int8 *p_char),
        ssize_t (__fastcall *write_to_file)(int *p_fd, char *data_to_write, size_t len_to_write),
        int *p_fd)
{
  unsigned int current_char_2; // r5
  size_t len_to_write; // r4
  int len_end_data; // r11
  int has_encountered_at_sign; // r6
  unsigned int current_char_3; // r0
  int ret; // r0
  int current_char_1; // r3
  ssize_t len_written; // r0
  unsigned int ret_2; // r3
  ssize_t len_written_1; // r0
  unsigned int ret_3; // r3
  ssize_t len_written_2; // r0
  unsigned int ret_4; // r3
  int was_last_write_success_1; // r3
  size_t len_to_write_final; // r4
  ssize_t len_written_final; // r0
  unsigned int ret_5; // r3
  unsigned int ret_1; // [sp+0h] [bp-20h]
  unsigned __int8 current_char; // [sp+1Fh] [bp-1h] BYREF
  _BYTE data_to_write[1028]; // [sp+20h] [bp+0h] BYREF

  current_char_2 = 0xFFFFFFFF;
  ret_1 = 0;
b_restart_from_scratch:
  len_to_write = 0;
  memset(data_to_write, 0, 0x401u);
  len_end_data = 0;
  has_encountered_at_sign = 0;
  current_char_3 = current_char_2;
  while ( 1 )
  {
    current_char = 0;
    if ( current_char_3 == 0xFFFFFFFF )
    {
      // get one character from pjl_ctx->pData
      ret = pjl_getc(&current_char);
      current_char_1 = current_char;
    }
    else
    {
      // a previous character was already retrieved, let's use that for now
      current_char_1 = (unsigned __int8)current_char_3;
      ret = 1;                                  // success
      current_char = current_char_1;
    }

    if ( has_encountered_at_sign )
      break;                                    // exit the loop forever

    // is it an '@' sign for a PJL-specific command?
    if ( current_char_1 != '@' )
      goto b_read_pjl_data;

    len_end_data = 1;
    has_encountered_at_sign = 1;
b_handle_pjl_at_sign:

    // from here, current_char == '@'
    if ( len_to_write + 13 > 0x400 )            // ?
    {
      if ( was_last_write_success )
      {
        len_written = write_to_file(p_fd, data_to_write, len_to_write);
        was_last_write_success = len_to_write == len_written;
        current_char_2 = '@';
        ret_2 = ret_1;
        if ( len_to_write != len_written )
          ret_2 = 0xFFFFFFFF;
        ret_1 = ret_2;
      }
      else
      {
        current_char_2 = '@';
      }

      goto b_restart_from_scratch;
    }
b_read_pjl_data:
    if ( ret == 0xFFFFFFFF )                    // error
    {
      if ( !was_last_write_success )
        return ret_1;

      len_written_1 = write_to_file(p_fd, data_to_write, len_to_write);
      ret_3 = ret_1;
      if ( len_to_write != len_written_1 )
        return 0xFFFFFFFF;                      // error
      return ret_3;
    }

    if ( len_to_write > 0x400 )
      __und(0);

    // append data to stack buffer
    data_to_write[len_to_write++] = current_char_1;
    current_char_3 = 0xFFFFFFFF;                // reset to enforce reading another character
                                                // at next loop iteration

    // reached 0x400 bytes to write, let's write them
    if ( len_to_write == 0x400 )
    {
      current_char_2 = 0xFFFFFFFF;              // reset to enforce reading another character
                                                // at next loop iteration
      if ( was_last_write_success )
      {
        len_written_2 = write_to_file(p_fd, data_to_write, 0x400);
        ret_4 = ret_1;
        if ( len_written_2 != 0x400 )
          ret_4 = 0xFFFFFFFF;
        ret_1 = ret_4;
        was_last_write_success_1 = was_last_write_success;
        if ( len_written_2 != 0x400 )
          was_last_write_success_1 = 0;
        was_last_write_success = was_last_write_success_1;
      }
      goto b_restart_from_scratch;
    }
  }                                             // end of while ( 1 )

  // we reach here if we encountered an '@' sign
  // let's check it is a valid "@PJL END DATA" footer
  if ( (unsigned __int8)aPjlEndData[len_end_data] != current_char_1 )
  {
    len_end_data = 1;
    has_encountered_at_sign = 0;                // reset so we read it again?
    goto b_read_data_or_at;
  }

  if ( len_end_data != 12 )                     // len("PJL END DATA") = 12
  {
    ++len_end_data;
b_read_data_or_at:
    // will go back to the while(1) loop but exit at the next
    // iteration due to "break" and has_encountered_at_sign == 1
    if ( current_char_1 != '@' )
      goto b_read_pjl_data;
    goto b_handle_pjl_at_sign;
  }

  // we reach here if all "PJL END DATA" was parsed
  current_char = 0;
  pjl_getc(&current_char);                      // read '\r'
  if ( current_char == '\r' )
    pjl_getc(&current_char);                    // read '\n'

  // write all the remaining data (len < 0x400), except the "PJL END DATA" footer
  len_to_write_final = len_to_write - 0xC;
  if ( !was_last_write_success )
    return ret_1;
  len_written_final = write_to_file(p_fd, data_to_write, len_to_write_final);
  ret_5 = ret_1;
  if ( len_to_write_final != len_written_final )
    return 0xFFFFFFFF;
  return ret_5;
}