| 1 | #include <stdlib.h> |
| 2 | #include <unistd.h> |
| 3 | #include <string.h> |
| 4 | |
| 5 | #include "tape_block.hh" |
| 6 | #include "data_block.hh" |
| 7 | #include "data_block_0.hh" |
| 8 | |
| 9 | #include "silent_code.hh" |
| 10 | #include "hw_constants.hh" |
| 11 | |
| 12 | |
| 13 | tape_block * tape_block::gen_from_fd(int fd, |
| 14 | void(*input_start)(void *), |
| 15 | void (*input_stop)(void *), |
| 16 | void * start_stop_arg) |
| 17 | { |
| 18 | tape_block * res_block; |
| 19 | res_block=new tape_block(fd,input_start,input_stop,start_stop_arg); |
| 20 | data_block * d_block; |
| 21 | data_block_0 * d0_block; |
| 22 | |
| 23 | // Retype to data_block if possible |
| 24 | switch(res_block->get_type()){ |
| 25 | case tape_block::TBT_DATA: // Make pointer a data block |
| 26 | d_block=new data_block(*res_block); |
| 27 | delete res_block; |
| 28 | res_block=d_block; |
| 29 | break; |
| 30 | default: // All other cases |
| 31 | return res_block; |
| 32 | } |
| 33 | |
| 34 | // Retype again, if it's a data_block now |
| 35 | |
| 36 | switch(res_block->get_type()){ |
| 37 | case 00: |
| 38 | d0_block=new data_block_0(*d_block); |
| 39 | d_block=d0_block; |
| 40 | break; |
| 41 | // case 01: d_block=new data_block_1(*d_block); break; |
| 42 | // case 02: d_block=new data_block_2(*d_block); break; |
| 43 | // case 03: d_block=new data_block_3(*d_block); break; |
| 44 | // case 04: d_block=new data_block_4(*d_block); break; |
| 45 | // case 05: d_block=new data_block_5(*d_block); break; |
| 46 | // case 06: d_block=new data_block_6(*d_block); break; |
| 47 | // case 07: d_block=new data_block_7(*d_block); break; |
| 48 | default: |
| 49 | return res_block; |
| 50 | } |
| 51 | delete res_block; |
| 52 | res_block=d_block; |
| 53 | |
| 54 | if (res_block->get_type()==0) switch(d0_block->get_subtype()){ |
| 55 | // case 000: d0_block=new data_block_0_00(d0_block); break; |
| 56 | // case 001: d0_block=new data_block_0_01(d0_block); break; |
| 57 | // case 002: d0_block=new data_block_0_02(d0_block); break; |
| 58 | // case 003: d0_block=new data_block_0_03(d0_block); break; |
| 59 | // case 004: d0_block=new data_block_0_04(d0_block); break; |
| 60 | // case 010: d0_block=new data_block_0_10(d0_block); break; |
| 61 | // case 014: d0_block=new data_block_0_14(d0_block); break; |
| 62 | // case 024: d0_block=new data_block_0_24(d0_block); break; |
| 63 | // case 030: d0_block=new data_block_0_30(d0_block); break; |
| 64 | // case 054: d0_block=new data_block_0_54(d0_block); break; |
| 65 | // case 060: d0_block=new data_block_0_60(d0_block); break; |
| 66 | default: |
| 67 | return res_block; |
| 68 | } |
| 69 | delete res_block; |
| 70 | res_block=d0_block; |
| 71 | |
| 72 | return res_block; |
| 73 | } |
| 74 | |
| 75 | /*! |
| 76 | *\brief Default constructor. |
| 77 | */ |
| 78 | tape_block::tape_block(){} |
| 79 | |
| 80 | |
| 81 | tape_block::tape_block(tape_block & org){ |
| 82 | block_type=org.block_type; |
| 83 | init_state=org.init_state; |
| 84 | data_read=org.data_read; |
| 85 | raw_data=0; |
| 86 | raw_size=org.raw_size; |
| 87 | word_data=0; |
| 88 | word_size=org.word_size; |
| 89 | if (raw_size){ |
| 90 | raw_data=(unsigned char *)malloc(raw_size); |
| 91 | memcpy(raw_data,org.raw_data,raw_size); |
| 92 | } |
| 93 | if (word_size){ |
| 94 | word_data=(unsigned short *)malloc(word_size*sizeof(unsigned short)); |
| 95 | memcpy(word_data,org.word_data,word_size*sizeof(unsigned short)); |
| 96 | } |
| 97 | } |
| 98 | |
| 99 | /*! |
| 100 | *\brief Automatic constructor with file descriptor support |
| 101 | * |
| 102 | * This constructor is used to initialise the block read in the block's |
| 103 | * data via a file descriptor.\n |
| 104 | * This is done in the following way: |
| 105 | * - input_start() is called. |
| 106 | * - Data is read from fd. Stops on end of file or end of block |
| 107 | * or IO error. On EOF or IO error input_stop() is NOT called. |
| 108 | * - If there was no IO error the block's checksum is calculated |
| 109 | * and checked. |
| 110 | * - The block's type field is initialised. |
| 111 | * - input_stop() is called. |
| 112 | * |
| 113 | *\param fd A file descriptor where the read is taken from |
| 114 | *\param input_stop A pointer to a function called at the end of input |
| 115 | *\param input_start A pointer to a function called at the beginning |
| 116 | * of input |
| 117 | *\param start_stop_arg A pointer passed to input_start and input_stop(). |
| 118 | */ |
| 119 | tape_block::tape_block (int fd, |
| 120 | void(*input_start)(void *), |
| 121 | void (*input_stop)(void *), |
| 122 | void * start_stop_arg |
| 123 | ) |
| 124 | { |
| 125 | unsigned char buffer; |
| 126 | int retval; |
| 127 | int eot_needed=EOT_LENGTH; |
| 128 | int eob_needed=EOB_LENGTH; |
| 129 | int block_complete=0; |
| 130 | |
| 131 | block_type= TBT_DISCARD; |
| 132 | init_state= TBS_DEFAULT; |
| 133 | data_read = 0; |
| 134 | raw_data = 0; |
| 135 | raw_size = 0; |
| 136 | word_data = 0; |
| 137 | word_size = 0; |
| 138 | |
| 139 | if (input_start) input_start (start_stop_arg); |
| 140 | |
| 141 | /* Look for block start in input stream */ |
| 142 | do { |
| 143 | retval=read(fd, &buffer, 1); |
| 144 | if (retval == 0){ // End of file |
| 145 | block_type=TBT_DISCARD; |
| 146 | init_state=TBS_EOF_LEGAL; |
| 147 | return; |
| 148 | } |
| 149 | if (retval == -1){ // Error reading from fd |
| 150 | block_type=TBT_DISCARD; |
| 151 | init_state=TBS_IOERR; |
| 152 | return; |
| 153 | } |
| 154 | data_read++; |
| 155 | |
| 156 | /* Look for end ot tape sequence */ |
| 157 | switch(eot_needed){ |
| 158 | case 3: |
| 159 | if (buffer==EOT_SEQ_1) eot_needed--; |
| 160 | else eot_needed=EOT_LENGTH; |
| 161 | break; |
| 162 | case 2: |
| 163 | if (buffer==EOT_SEQ_2) eot_needed--; |
| 164 | else eot_needed=EOT_LENGTH; |
| 165 | break; |
| 166 | case 1: |
| 167 | if (buffer==EOT_SEQ_3){ |
| 168 | raw_data=(unsigned char*)malloc(3); |
| 169 | raw_size=3; |
| 170 | raw_data[0]=EOT_SEQ_1; |
| 171 | raw_data[1]=EOT_SEQ_2; |
| 172 | raw_data[2]=EOT_SEQ_3; |
| 173 | block_type =TBT_EOT; |
| 174 | init_state =TBS_OK; |
| 175 | return; |
| 176 | } |
| 177 | else eot_needed=EOT_LENGTH; |
| 178 | break; |
| 179 | } |
| 180 | } while (buffer != (unsigned char) BLOCK_START_DELIMITER); |
| 181 | |
| 182 | |
| 183 | /* Now input the block data */ |
| 184 | block_complete = 0; |
| 185 | do { |
| 186 | retval = read (fd, &buffer, 1); |
| 187 | |
| 188 | if (retval == 0){ // End of file |
| 189 | block_type=TBT_DISCARD; |
| 190 | init_state=TBS_EOF_ILLEGAL; |
| 191 | return; |
| 192 | } |
| 193 | if (retval == -1){ // Error reading from fd |
| 194 | block_type=TBT_DISCARD; |
| 195 | init_state=TBS_IOERR; |
| 196 | return; |
| 197 | } |
| 198 | data_read++; // We have consumed a byte |
| 199 | |
| 200 | /* sort in the new byte */ |
| 201 | raw_size++; |
| 202 | raw_data=(unsigned char*)realloc(raw_data,raw_size); |
| 203 | raw_data[raw_size-1]=buffer; |
| 204 | |
| 205 | /* Look for end ot block sequence */ |
| 206 | switch(eob_needed){ |
| 207 | case 2: |
| 208 | if (buffer==BLOCK_END_DELIMITER_1) eob_needed--; |
| 209 | else eob_needed=EOB_LENGTH; |
| 210 | break; |
| 211 | case 1: |
| 212 | if (buffer==BLOCK_END_DELIMITER_2){ |
| 213 | raw_size-=EOB_LENGTH; // Don't want the delimiter(s) in the data! |
| 214 | raw_data=(unsigned char*)realloc(raw_data,raw_size); |
| 215 | block_complete=1; |
| 216 | } |
| 217 | else eob_needed=EOB_LENGTH; |
| 218 | break; |
| 219 | } |
| 220 | }while (!block_complete); |
| 221 | if (input_stop) input_stop (start_stop_arg); |
| 222 | |
| 223 | /* Now we have the data in. */ |
| 224 | |
| 225 | if (init_words()!=0){ |
| 226 | init_state=TBS_CHECKSUM; |
| 227 | return; |
| 228 | } |
| 229 | |
| 230 | if (test_checksum()!=0){ |
| 231 | init_state=TBS_CHECKSUM; |
| 232 | return; |
| 233 | } |
| 234 | |
| 235 | block_type=TBT_DATA; |
| 236 | init_state=TBS_OK; |
| 237 | } |
| 238 | |
| 239 | /*! |
| 240 | *\brief Default destructor. |
| 241 | */ |
| 242 | tape_block::~tape_block(){ |
| 243 | free(raw_data); |
| 244 | free(word_data); |
| 245 | } |
| 246 | |
| 247 | /*! |
| 248 | *\brief Query the block's state. |
| 249 | * |
| 250 | * If the state is not TBS_OK, the block must be discarded. |
| 251 | *\return The block's initialisation state |
| 252 | */ |
| 253 | tape_block::tb_state_t tape_block::get_state(){ |
| 254 | return init_state; |
| 255 | } |
| 256 | |
| 257 | |
| 258 | /*! |
| 259 | *\brief Get size of the internal raw data buffer |
| 260 | *\return The size of the internal raw data buffer |
| 261 | */ |
| 262 | int tape_block::get_raw_size(){ |
| 263 | return raw_size; |
| 264 | } |
| 265 | |
| 266 | /*! |
| 267 | *\brief Access internal raw data buffer |
| 268 | * |
| 269 | * The raw data buffer contains all block data except the \ \ |
| 270 | * block start delimiter and block end delimiter. |
| 271 | *\return Pointer to internal raw data buffer of the block |
| 272 | */ |
| 273 | unsigned char * tape_block::get_raw_data(){ |
| 274 | return raw_data; |
| 275 | } |
| 276 | |
| 277 | /*! |
| 278 | *\brief Determine the block's type |
| 279 | * |
| 280 | * This routine returns the block's type.\\ |
| 281 | *\retval TBT_DATA if it's a data block |
| 282 | *\retval TBT_EOT if it's an end of tape mark |
| 283 | *\retval TBR_DISCARD if the block is unusable |
| 284 | * |
| 285 | *\note This function is virtual. That means that if the tape block in |
| 286 | * question is of the subtype data_block which overwrites this method, |
| 287 | * it will return the block type contained in the upper 4 bits of the |
| 288 | * first data word! Try to avoid testing for TBT_DATA. \n |
| 289 | * Blocks generated by gen_from_fd should never have TBT_DATA. |
| 290 | */ |
| 291 | int tape_block::get_type(){ |
| 292 | return block_type; |
| 293 | } |
| 294 | |
| 295 | /*! |
| 296 | *\brief Determine the block's subtype |
| 297 | * |
| 298 | * Some data block types have a subtype. |
| 299 | *\note This is to be used in derived classes. |
| 300 | *\return Always 0 |
| 301 | */ |
| 302 | int tape_block::get_subtype(){ |
| 303 | return 0; |
| 304 | } |
| 305 | |
| 306 | |
| 307 | /*! |
| 308 | *\brief Initialize word representation of data |
| 309 | *\retval 0 on success |
| 310 | *\retval 1 on error |
| 311 | */ |
| 312 | int tape_block::init_words(){ |
| 313 | word_size=raw_size/3; |
| 314 | if (word_size<MINIMUM_DATA_BLOCK_WORDSIZE) return 1; // Block too short! |
| 315 | word_data=(unsigned short *)malloc(raw_size*sizeof(unsigned short)); |
| 316 | for (int pos=0; pos<word_size; pos++) |
| 317 | word_data[pos]=combine466(raw_data+3*pos); |
| 318 | return 0; |
| 319 | } |
| 320 | |
| 321 | /*! |
| 322 | *\brief Calculate and check checksum |
| 323 | *\retval 0 on success |
| 324 | *\retval 1 on error |
| 325 | */ |
| 326 | int tape_block::test_checksum(){ |
| 327 | unsigned short sum=0; |
| 328 | for (int pos=0; pos<word_size-1;pos++) |
| 329 | sum^=word_data[pos]; |
| 330 | if (sum==word_data[word_size-1]) return 0; |
| 331 | else return 1; |
| 332 | } |