src/HexProgram.cpp

   1 /*
   2  *      avr-sim: An atmel AVR simulator
   3  *  Copyright (C) 2008  Tom Haber
   4  *
   5  *  This program is free software: you can redistribute it and/or modify
   6  *  it under the terms of the GNU General Public License as published by
   7  *  the Free Software Foundation, either version 3 of the License, or
   8  *  (at your option) any later version.
   9
  10  *  This program is distributed in the hope that it will be useful,
  11  *  but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  *  GNU General Public License for more details.
  14  *
  15  *  You should have received a copy of the GNU General Public License
  16  *  along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17  */
  18
  19 #include "HexProgram.h"
  20 #include "Format.h"
  21 #include "RuntimeException.h"
  22
  23 #include <string>
  24 #include <iostream>
  25 #include <memory.h>
  26
  27 namespace avr {
  28
  29         void HexProgram::load(const char *filename) {
  30                 if( f.is_open() )
  31                         f.close();
  32
  33                 f.open( filename );
  34
  35                 if( ! f.is_open() )
  36                         throw util::RuntimeException( util::format("Could not open file: %s") % filename );
  37
  38                 end = false;
  39                 offset = 0;
  40         }
  41
  42         HexProgram::~HexProgram() {
  43                 if( f.is_open() )
  44                         f.close();
  45         }
  46
  47         /* Convert a hexidecimal digit to a 4 bit nibble. */
  48         static int hex2nib( char hex ) {
  49             if( (hex >= 'A') && (hex <= 'F') )
  50                 return (10 + (hex - 'A'));
  51
  52             else if( (hex >= 'a') && (hex <= 'f') )
  53                 return (10 + (hex - 'a'));
  54
  55             else if( (hex >= '0') && (hex <= '9') )
  56                 return (hex - '0');
  57
  58             return -1;
  59         }
  60
  61         static bool hex2bytes(const std::string & hex, size_t length,
  62                                                         unsigned char bytes[]) {
  63
  64                 size_t off = 1;
  65                 for(size_t i = 0; i < length; ++i) {
  66                         int valh = hex2nib( hex[off++] );
  67                         int vall = hex2nib( hex[off++] );
  68                         if( (valh == -1) && (vall == -1) )
  69                                 return false;
  70
  71                         bytes[i] = (valh << 4) | vall;
  72                 }
  73
  74                 return true;
  75         }
  76
  77         bool HexProgram::readNextSection(Section & s) {
  78                 if( end || f.eof() )
  79                         return false;
  80
  81                 bool found = false;
  82                 do {
  83                         std::string line;
  84                         std::getline(f, line);
  85
  86                         if( line[0] != ':' )
  87                                 continue;
  88
  89                         size_t length = (line.size() - 1) / 2;
  90                         unsigned char bytes[length];
  91                         hex2bytes(line, length, bytes);
  92
  93                         unsigned char crc = 0;
  94                         for(size_t i = 0; i < length; ++i)
  95                                 crc += bytes[i];
  96
  97                         if( crc != 0 ) {
  98                                 std::cerr << "Invalid crc checksum" << std::endl;
  99                                 continue;
 100                         }
 101
 102                         const unsigned char rec_length = bytes[0];
 103                         if( length - 5 != rec_length ) {
 104                                 std::cerr << "Invalid record length" << std::endl;
 105                                 continue;
 106                         }
 107
 108                         unsigned int addr = bytes[1] << 16 | bytes[2];
 109
 110                         const unsigned char rec_type = bytes[3];
 111                         switch( rec_type ) {
 112                                 case 0: // Data record
 113                                         s.init(Section::FLASH, addr + offset, rec_length);
 114                                         memcpy( s.data(), &bytes[4], rec_length );
 115                                         found = true;
 116                                         break;
 117
 118                                 case 1: // End-of-file record
 119                                         end = true;
 120                                         found = true;
 121                                         break;
 122
 123                                 case 2: // Extended 8086 Segment Record
 124                             if( rec_length != 2 ) {
 125                                 std::cerr <<  "Bad Extended 8086 Segment Record" << std::endl;
 126                                 continue;
 127                             }
 128
 129                             offset = (bytes[4]<<16 | bytes[5]) * 16;
 130                             break;
 131
 132                                 case 3:  // Start Segment Address Record
 133                                         break;
 134
 135                                 case 4: // Extended Linear Address Record
 136                             if( rec_length != 2 ) {
 137                                 std::cerr <<  "Bad Extended Linear Address Record" << std::endl;
 138                                 continue;
 139                             }
 140
 141                             offset = (bytes[4]<<16 | bytes[5]) * 65536;
 142                                         break;
 143
 144                                 case 5: // Start Linear Address Record
 145                                         break;
 146                         }
 147
 148                 } while( ! found && ! f.eof() );
 149
 150                 return found;
 151         }
 152
 153 }