[07a3253d] | 1 | /* |
---|
| 2 | * IMFS Device Node Handlers |
---|
| 3 | * |
---|
| 4 | * This file contains the set of handlers used to process operations on |
---|
| 5 | * IMFS memory file nodes. The memory files are created in memory using |
---|
| 6 | * malloc'ed memory. Thus any data stored in one of these files is lost |
---|
| 7 | * at system shutdown unless special arrangements to copy the data to |
---|
| 8 | * some type of non-volailte storage are made by the application. |
---|
| 9 | * |
---|
[08311cc3] | 10 | * COPYRIGHT (c) 1989-1999. |
---|
[07a3253d] | 11 | * On-Line Applications Research Corporation (OAR). |
---|
| 12 | * |
---|
| 13 | * The license and distribution terms for this file may be |
---|
| 14 | * found in the file LICENSE in this distribution or at |
---|
| 15 | * http://www.OARcorp.com/rtems/license.html. |
---|
| 16 | * |
---|
| 17 | * $Id$ |
---|
| 18 | */ |
---|
| 19 | |
---|
[d6b1d73] | 20 | #if HAVE_CONFIG_H |
---|
| 21 | #include "config.h" |
---|
| 22 | #endif |
---|
| 23 | |
---|
[07a3253d] | 24 | #include <stdlib.h> |
---|
| 25 | #include <assert.h> |
---|
| 26 | #include <errno.h> |
---|
| 27 | |
---|
| 28 | #include <rtems.h> |
---|
| 29 | #include <rtems/libio.h> |
---|
| 30 | #include "imfs.h" |
---|
[c058578] | 31 | #include <rtems/libio_.h> |
---|
[b2709481] | 32 | #include <rtems/seterr.h> |
---|
[07a3253d] | 33 | |
---|
| 34 | #define MEMFILE_STATIC |
---|
| 35 | |
---|
| 36 | /* |
---|
| 37 | * Prototypes of private routines |
---|
| 38 | */ |
---|
| 39 | |
---|
| 40 | MEMFILE_STATIC int IMFS_memfile_extend( |
---|
| 41 | IMFS_jnode_t *the_jnode, |
---|
| 42 | off_t new_length |
---|
| 43 | ); |
---|
| 44 | |
---|
| 45 | MEMFILE_STATIC int IMFS_memfile_addblock( |
---|
| 46 | IMFS_jnode_t *the_jnode, |
---|
| 47 | unsigned int block |
---|
| 48 | ); |
---|
| 49 | |
---|
| 50 | MEMFILE_STATIC int IMFS_memfile_remove_block( |
---|
| 51 | IMFS_jnode_t *the_jnode, |
---|
| 52 | unsigned int block |
---|
| 53 | ); |
---|
| 54 | |
---|
| 55 | MEMFILE_STATIC block_p *IMFS_memfile_get_block_pointer( |
---|
| 56 | IMFS_jnode_t *the_jnode, |
---|
| 57 | unsigned int block, |
---|
| 58 | int malloc_it |
---|
| 59 | ); |
---|
| 60 | |
---|
| 61 | MEMFILE_STATIC int IMFS_memfile_read( |
---|
| 62 | IMFS_jnode_t *the_jnode, |
---|
| 63 | off_t start, |
---|
| 64 | unsigned char *destination, |
---|
| 65 | unsigned int length |
---|
| 66 | ); |
---|
| 67 | |
---|
| 68 | MEMFILE_STATIC int IMFS_memfile_write( |
---|
| 69 | IMFS_jnode_t *the_jnode, |
---|
| 70 | off_t start, |
---|
| 71 | const unsigned char *source, |
---|
| 72 | unsigned int length |
---|
| 73 | ); |
---|
| 74 | |
---|
| 75 | void *memfile_alloc_block(void); |
---|
| 76 | |
---|
| 77 | void memfile_free_block( |
---|
| 78 | void *memory |
---|
| 79 | ); |
---|
| 80 | |
---|
| 81 | /* |
---|
| 82 | * memfile_open |
---|
| 83 | * |
---|
| 84 | * This routine processes the open() system call. Note that there is |
---|
| 85 | * nothing special to be done at open() time. |
---|
| 86 | */ |
---|
| 87 | |
---|
| 88 | int memfile_open( |
---|
| 89 | rtems_libio_t *iop, |
---|
| 90 | const char *pathname, |
---|
| 91 | unsigned32 flag, |
---|
| 92 | unsigned32 mode |
---|
| 93 | ) |
---|
| 94 | { |
---|
| 95 | IMFS_jnode_t *the_jnode; |
---|
| 96 | |
---|
| 97 | the_jnode = iop->file_info; |
---|
| 98 | |
---|
[e42a135] | 99 | if (iop->flags & LIBIO_FLAGS_APPEND) |
---|
| 100 | iop->offset = the_jnode->info.file.size; |
---|
| 101 | |
---|
[eb22ebe] | 102 | iop->size = the_jnode->info.file.size; |
---|
[07a3253d] | 103 | return 0; |
---|
| 104 | } |
---|
| 105 | |
---|
| 106 | /* |
---|
| 107 | * memfile_close |
---|
| 108 | * |
---|
| 109 | * This routine processes the close() system call. Note that there is |
---|
| 110 | * nothing to flush or memory to free at this point. |
---|
| 111 | */ |
---|
| 112 | |
---|
| 113 | int memfile_close( |
---|
| 114 | rtems_libio_t *iop |
---|
| 115 | ) |
---|
| 116 | { |
---|
| 117 | IMFS_jnode_t *the_jnode; |
---|
| 118 | |
---|
| 119 | the_jnode = iop->file_info; |
---|
| 120 | |
---|
[dd19c0b] | 121 | if (iop->flags & LIBIO_FLAGS_APPEND) |
---|
| 122 | iop->offset = the_jnode->info.file.size; |
---|
| 123 | |
---|
[07a3253d] | 124 | return 0; |
---|
| 125 | } |
---|
| 126 | |
---|
| 127 | /* |
---|
| 128 | * memfile_read |
---|
| 129 | * |
---|
| 130 | * This routine processes the read() system call. |
---|
| 131 | */ |
---|
| 132 | |
---|
| 133 | int memfile_read( |
---|
| 134 | rtems_libio_t *iop, |
---|
| 135 | void *buffer, |
---|
| 136 | unsigned32 count |
---|
| 137 | ) |
---|
| 138 | { |
---|
| 139 | IMFS_jnode_t *the_jnode; |
---|
| 140 | |
---|
| 141 | the_jnode = iop->file_info; |
---|
| 142 | |
---|
| 143 | return IMFS_memfile_read( the_jnode, iop->offset, buffer, count ); |
---|
| 144 | } |
---|
| 145 | |
---|
| 146 | /* |
---|
| 147 | * memfile_write |
---|
| 148 | * |
---|
| 149 | * This routine processes the write() system call. |
---|
| 150 | */ |
---|
| 151 | |
---|
| 152 | int memfile_write( |
---|
| 153 | rtems_libio_t *iop, |
---|
| 154 | const void *buffer, |
---|
| 155 | unsigned32 count |
---|
| 156 | ) |
---|
| 157 | { |
---|
| 158 | IMFS_jnode_t *the_jnode; |
---|
[efb1b830] | 159 | int status; |
---|
[07a3253d] | 160 | |
---|
| 161 | the_jnode = iop->file_info; |
---|
| 162 | |
---|
[efb1b830] | 163 | status = IMFS_memfile_write( the_jnode, iop->offset, buffer, count ); |
---|
| 164 | iop->size = the_jnode->info.file.size; |
---|
| 165 | |
---|
| 166 | return status; |
---|
[07a3253d] | 167 | } |
---|
| 168 | |
---|
| 169 | /* |
---|
| 170 | * memfile_ioctl |
---|
| 171 | * |
---|
| 172 | * This routine processes the ioctl() system call. |
---|
| 173 | * |
---|
| 174 | * NOTE: No ioctl()'s are supported for in-memory files. |
---|
| 175 | */ |
---|
| 176 | |
---|
| 177 | int memfile_ioctl( |
---|
| 178 | rtems_libio_t *iop, |
---|
| 179 | unsigned32 command, |
---|
| 180 | void *buffer |
---|
| 181 | ) |
---|
| 182 | { |
---|
| 183 | IMFS_jnode_t *the_jnode; |
---|
| 184 | |
---|
| 185 | the_jnode = iop->file_info; |
---|
| 186 | |
---|
| 187 | return 0; |
---|
| 188 | } |
---|
| 189 | |
---|
| 190 | /* |
---|
| 191 | * memfile_lseek |
---|
| 192 | * |
---|
| 193 | * This routine processes the lseek() system call. |
---|
| 194 | */ |
---|
| 195 | |
---|
| 196 | int memfile_lseek( |
---|
| 197 | rtems_libio_t *iop, |
---|
| 198 | off_t offset, |
---|
| 199 | int whence |
---|
| 200 | ) |
---|
| 201 | { |
---|
| 202 | IMFS_jnode_t *the_jnode; |
---|
| 203 | |
---|
| 204 | the_jnode = iop->file_info; |
---|
| 205 | |
---|
[d1941587] | 206 | if (the_jnode->type == IMFS_LINEAR_FILE) { |
---|
| 207 | if (iop->offset > the_jnode->info.linearfile.size) |
---|
| 208 | iop->offset = the_jnode->info.linearfile.size; |
---|
| 209 | } |
---|
| 210 | else { /* Must be a block file (IMFS_MEMORY_FILE). */ |
---|
| 211 | if (IMFS_memfile_extend( the_jnode, iop->offset )) |
---|
[b2709481] | 212 | rtems_set_errno_and_return_minus_one( ENOSPC ); |
---|
[07a3253d] | 213 | |
---|
[d1941587] | 214 | iop->size = the_jnode->info.file.size; |
---|
| 215 | } |
---|
[efb1b830] | 216 | return iop->offset; |
---|
[07a3253d] | 217 | } |
---|
| 218 | |
---|
| 219 | /* |
---|
| 220 | * memfile_stat |
---|
| 221 | * |
---|
| 222 | * This IMFS_stat() can be used. |
---|
| 223 | */ |
---|
| 224 | |
---|
| 225 | /* |
---|
| 226 | * memfile_ftruncate |
---|
| 227 | * |
---|
| 228 | * This routine processes the ftruncate() system call. |
---|
| 229 | */ |
---|
| 230 | |
---|
| 231 | int memfile_ftruncate( |
---|
| 232 | rtems_libio_t *iop, |
---|
| 233 | off_t length |
---|
| 234 | ) |
---|
| 235 | { |
---|
| 236 | IMFS_jnode_t *the_jnode; |
---|
| 237 | |
---|
| 238 | the_jnode = iop->file_info; |
---|
| 239 | |
---|
| 240 | /* |
---|
| 241 | * POSIX 1003.1b does not specify what happens if you truncate a file |
---|
| 242 | * and the new length is greater than the current size. We treat this |
---|
| 243 | * as an extend operation. |
---|
| 244 | */ |
---|
| 245 | |
---|
| 246 | if ( length > the_jnode->info.file.size ) |
---|
| 247 | return IMFS_memfile_extend( the_jnode, length ); |
---|
| 248 | |
---|
| 249 | /* |
---|
| 250 | * The in-memory files do not currently reclaim memory until the file is |
---|
| 251 | * deleted. So we leave the previously allocated blocks in place for |
---|
| 252 | * future use and just set the length. |
---|
| 253 | */ |
---|
| 254 | |
---|
| 255 | the_jnode->info.file.size = length; |
---|
[efb1b830] | 256 | iop->size = the_jnode->info.file.size; |
---|
[07a3253d] | 257 | |
---|
| 258 | IMFS_update_atime( the_jnode ); |
---|
| 259 | |
---|
| 260 | return 0; |
---|
| 261 | } |
---|
| 262 | |
---|
| 263 | /* |
---|
| 264 | * IMFS_memfile_extend |
---|
| 265 | * |
---|
| 266 | * This routine insures that the in-memory file is of the length |
---|
| 267 | * specified. If necessary, it will allocate memory blocks to |
---|
| 268 | * extend the file. |
---|
| 269 | */ |
---|
| 270 | |
---|
| 271 | MEMFILE_STATIC int IMFS_memfile_extend( |
---|
| 272 | IMFS_jnode_t *the_jnode, |
---|
| 273 | off_t new_length |
---|
| 274 | ) |
---|
| 275 | { |
---|
| 276 | unsigned int block; |
---|
| 277 | unsigned int new_blocks; |
---|
| 278 | unsigned int old_blocks; |
---|
| 279 | |
---|
| 280 | /* |
---|
| 281 | * Perform internal consistency checks |
---|
| 282 | */ |
---|
| 283 | |
---|
| 284 | assert( the_jnode ); |
---|
| 285 | if ( !the_jnode ) |
---|
[b2709481] | 286 | rtems_set_errno_and_return_minus_one( EIO ); |
---|
[07a3253d] | 287 | |
---|
| 288 | assert( the_jnode->type == IMFS_MEMORY_FILE ); |
---|
| 289 | if ( the_jnode->type != IMFS_MEMORY_FILE ) |
---|
[b2709481] | 290 | rtems_set_errno_and_return_minus_one( EIO ); |
---|
[07a3253d] | 291 | |
---|
| 292 | if ( new_length >= IMFS_MEMFILE_MAXIMUM_SIZE ) |
---|
[b2709481] | 293 | rtems_set_errno_and_return_minus_one( EINVAL ); |
---|
[07a3253d] | 294 | |
---|
| 295 | if ( new_length <= the_jnode->info.file.size ) |
---|
| 296 | return 0; |
---|
| 297 | |
---|
| 298 | /* |
---|
| 299 | * Calculate the number of range of blocks to allocate |
---|
| 300 | */ |
---|
| 301 | |
---|
| 302 | new_blocks = new_length / IMFS_MEMFILE_BYTES_PER_BLOCK; |
---|
| 303 | old_blocks = the_jnode->info.file.size / IMFS_MEMFILE_BYTES_PER_BLOCK; |
---|
| 304 | |
---|
| 305 | /* |
---|
| 306 | * Now allocate each of those blocks. |
---|
| 307 | */ |
---|
| 308 | |
---|
| 309 | for ( block=old_blocks ; block<=new_blocks ; block++ ) { |
---|
| 310 | if ( IMFS_memfile_addblock( the_jnode, block ) ) { |
---|
| 311 | for ( ; block>=old_blocks ; block-- ) { |
---|
| 312 | IMFS_memfile_remove_block( the_jnode, block ); |
---|
| 313 | } |
---|
[b2709481] | 314 | rtems_set_errno_and_return_minus_one( ENOSPC ); |
---|
[07a3253d] | 315 | } |
---|
| 316 | } |
---|
| 317 | |
---|
| 318 | /* |
---|
| 319 | * Set the new length of the file. |
---|
| 320 | */ |
---|
| 321 | |
---|
| 322 | the_jnode->info.file.size = new_length; |
---|
| 323 | return 0; |
---|
| 324 | } |
---|
| 325 | |
---|
| 326 | /* |
---|
| 327 | * IMFS_memfile_addblock |
---|
| 328 | * |
---|
| 329 | * This routine adds a single block to the specified in-memory file. |
---|
| 330 | */ |
---|
| 331 | |
---|
| 332 | MEMFILE_STATIC int IMFS_memfile_addblock( |
---|
| 333 | IMFS_jnode_t *the_jnode, |
---|
| 334 | unsigned int block |
---|
| 335 | ) |
---|
| 336 | { |
---|
| 337 | block_p memory; |
---|
| 338 | block_p *block_entry_ptr; |
---|
| 339 | |
---|
| 340 | assert( the_jnode ); |
---|
| 341 | if ( !the_jnode ) |
---|
[b2709481] | 342 | rtems_set_errno_and_return_minus_one( EIO ); |
---|
[07a3253d] | 343 | |
---|
| 344 | assert( the_jnode->type == IMFS_MEMORY_FILE ); |
---|
| 345 | if ( the_jnode->type != IMFS_MEMORY_FILE ) |
---|
[b2709481] | 346 | rtems_set_errno_and_return_minus_one( EIO ); |
---|
[07a3253d] | 347 | |
---|
| 348 | block_entry_ptr = IMFS_memfile_get_block_pointer( the_jnode, block, 1 ); |
---|
| 349 | if ( *block_entry_ptr ) |
---|
| 350 | return 0; |
---|
| 351 | |
---|
| 352 | #if 0 |
---|
| 353 | printf( "%d %p", block, block_entry_ptr ); |
---|
| 354 | fflush(stdout); |
---|
| 355 | #endif |
---|
| 356 | |
---|
| 357 | memory = memfile_alloc_block(); |
---|
| 358 | if ( !memory ) |
---|
| 359 | return 1; |
---|
| 360 | *block_entry_ptr = memory; |
---|
| 361 | |
---|
| 362 | return 0; |
---|
| 363 | } |
---|
| 364 | |
---|
| 365 | /* |
---|
| 366 | * IMFS_memfile_remove_block |
---|
| 367 | * |
---|
| 368 | * This routine removes the specified block from the in-memory file. |
---|
| 369 | * |
---|
| 370 | * NOTE: This is a support routine and is called only to remove |
---|
| 371 | * the last block or set of blocks in a file. Removing a |
---|
| 372 | * block from the middle of a file would be exceptionally |
---|
| 373 | * dangerous and the results unpredictable. |
---|
| 374 | */ |
---|
| 375 | |
---|
| 376 | MEMFILE_STATIC int IMFS_memfile_remove_block( |
---|
| 377 | IMFS_jnode_t *the_jnode, |
---|
| 378 | unsigned int block |
---|
| 379 | ) |
---|
| 380 | { |
---|
| 381 | block_p *block_entry_ptr; |
---|
| 382 | block_p ptr; |
---|
| 383 | |
---|
| 384 | block_entry_ptr = IMFS_memfile_get_block_pointer( the_jnode, block, 0 ); |
---|
| 385 | ptr = *block_entry_ptr; |
---|
| 386 | *block_entry_ptr = 0; |
---|
| 387 | |
---|
| 388 | memfile_free_block( ptr ); |
---|
| 389 | |
---|
| 390 | return 1; |
---|
| 391 | } |
---|
| 392 | |
---|
| 393 | /* |
---|
| 394 | * memfile_free_blocks_in_table |
---|
| 395 | * |
---|
| 396 | * This is a support routine for IMFS_memfile_remove. It frees all the |
---|
| 397 | * blocks in one of the indirection tables. |
---|
| 398 | */ |
---|
| 399 | |
---|
| 400 | void memfile_free_blocks_in_table( |
---|
| 401 | block_p **block_table, |
---|
| 402 | int entries |
---|
| 403 | ) |
---|
| 404 | { |
---|
| 405 | int i; |
---|
| 406 | block_p *b; |
---|
| 407 | |
---|
| 408 | /* |
---|
| 409 | * Perform internal consistency checks |
---|
| 410 | */ |
---|
| 411 | |
---|
| 412 | assert( block_table ); |
---|
| 413 | if ( !block_table ) |
---|
| 414 | return; |
---|
| 415 | |
---|
| 416 | /* |
---|
| 417 | * Now go through all the slots in the table and free the memory. |
---|
| 418 | */ |
---|
| 419 | |
---|
| 420 | b = *block_table; |
---|
| 421 | |
---|
| 422 | for ( i=0 ; i<entries ; i++ ) { |
---|
| 423 | if ( b[i] ) { |
---|
| 424 | memfile_free_block( b[i] ); |
---|
| 425 | b[i] = 0; |
---|
| 426 | } |
---|
| 427 | } |
---|
| 428 | |
---|
| 429 | /* |
---|
| 430 | * Now that all the blocks in the block table are free, we can |
---|
| 431 | * free the block table itself. |
---|
| 432 | */ |
---|
| 433 | |
---|
| 434 | memfile_free_block( *block_table ); |
---|
| 435 | *block_table = 0; |
---|
| 436 | } |
---|
| 437 | |
---|
| 438 | /* |
---|
| 439 | * IMFS_memfile_remove |
---|
| 440 | * |
---|
| 441 | * This routine frees all memory associated with an in memory file. |
---|
| 442 | * |
---|
| 443 | * NOTE: This is an exceptionally conservative implementation. |
---|
| 444 | * It will check EVERY pointer which is non-NULL and insure |
---|
| 445 | * any child non-NULL pointers are freed. Optimistically, all that |
---|
| 446 | * is necessary is to scan until a NULL pointer is found. There |
---|
| 447 | * should be no allocated data past that point. |
---|
| 448 | * |
---|
| 449 | * In experimentation on the powerpc simulator, it was noted |
---|
| 450 | * that using blocks which held 128 slots versus 16 slots made |
---|
| 451 | * a significant difference in the performance of this routine. |
---|
| 452 | * |
---|
| 453 | * Regardless until the IMFS implementation is proven, it |
---|
| 454 | * is better to stick to simple, easy to understand algorithms. |
---|
| 455 | */ |
---|
| 456 | |
---|
| 457 | int IMFS_memfile_remove( |
---|
| 458 | IMFS_jnode_t *the_jnode |
---|
| 459 | ) |
---|
| 460 | { |
---|
| 461 | IMFS_memfile_t *info; |
---|
| 462 | int i; |
---|
| 463 | int j; |
---|
| 464 | unsigned int to_free; |
---|
| 465 | block_p *p; |
---|
| 466 | |
---|
| 467 | /* |
---|
| 468 | * Perform internal consistency checks |
---|
| 469 | */ |
---|
| 470 | |
---|
| 471 | assert( the_jnode ); |
---|
| 472 | if ( !the_jnode ) |
---|
[b2709481] | 473 | rtems_set_errno_and_return_minus_one( EIO ); |
---|
[07a3253d] | 474 | |
---|
| 475 | assert( the_jnode->type == IMFS_MEMORY_FILE ); |
---|
| 476 | if ( the_jnode->type != IMFS_MEMORY_FILE ) |
---|
[b2709481] | 477 | rtems_set_errno_and_return_minus_one( EIO ); |
---|
[07a3253d] | 478 | |
---|
| 479 | /* |
---|
| 480 | * Eventually this could be set smarter at each call to |
---|
| 481 | * memfile_free_blocks_in_table to greatly speed this up. |
---|
| 482 | */ |
---|
| 483 | |
---|
| 484 | to_free = IMFS_MEMFILE_BLOCK_SLOTS; |
---|
| 485 | |
---|
| 486 | /* |
---|
| 487 | * Now start freeing blocks in this order: |
---|
| 488 | * + indirect |
---|
| 489 | * + doubly indirect |
---|
| 490 | * + triply indirect |
---|
| 491 | */ |
---|
| 492 | |
---|
| 493 | info = &the_jnode->info.file; |
---|
| 494 | |
---|
| 495 | if ( info->indirect ) { |
---|
| 496 | memfile_free_blocks_in_table( &info->indirect, to_free ); |
---|
| 497 | } |
---|
| 498 | |
---|
| 499 | if ( info->doubly_indirect ) { |
---|
| 500 | |
---|
| 501 | for ( i=0 ; i<IMFS_MEMFILE_BLOCK_SLOTS ; i++ ) { |
---|
| 502 | if ( info->doubly_indirect[i] ) { |
---|
| 503 | memfile_free_blocks_in_table( |
---|
| 504 | (block_p **)&info->doubly_indirect[i], to_free ); |
---|
| 505 | } |
---|
| 506 | } |
---|
| 507 | memfile_free_blocks_in_table( &info->doubly_indirect, to_free ); |
---|
| 508 | |
---|
| 509 | } |
---|
| 510 | |
---|
| 511 | if ( info->triply_indirect ) { |
---|
| 512 | for ( i=0 ; i<IMFS_MEMFILE_BLOCK_SLOTS ; i++ ) { |
---|
| 513 | p = (block_p *) info->triply_indirect[i]; |
---|
[d79ef17] | 514 | if ( !p ) /* ensure we have a valid pointer */ |
---|
| 515 | break; |
---|
[07a3253d] | 516 | for ( j=0 ; j<IMFS_MEMFILE_BLOCK_SLOTS ; j++ ) { |
---|
| 517 | if ( p[j] ) { |
---|
| 518 | memfile_free_blocks_in_table( (block_p **)&p[j], to_free); |
---|
| 519 | } |
---|
| 520 | } |
---|
| 521 | memfile_free_blocks_in_table( |
---|
| 522 | (block_p **)&info->triply_indirect[i], to_free ); |
---|
| 523 | } |
---|
| 524 | memfile_free_blocks_in_table( |
---|
| 525 | (block_p **)&info->triply_indirect, to_free ); |
---|
| 526 | } |
---|
| 527 | |
---|
| 528 | return 0; |
---|
| 529 | } |
---|
| 530 | |
---|
| 531 | /* |
---|
| 532 | * IMFS_memfile_read |
---|
| 533 | * |
---|
| 534 | * This routine read from memory file pointed to by the_jnode into |
---|
| 535 | * the specified data buffer specified by destination. The file |
---|
| 536 | * is NOT extended. An offset greater than the length of the file |
---|
| 537 | * is considered an error. Read from an offset for more bytes than |
---|
| 538 | * are between the offset and the end of the file will result in |
---|
| 539 | * reading the data between offset and the end of the file (truncated |
---|
| 540 | * read). |
---|
| 541 | */ |
---|
| 542 | |
---|
| 543 | MEMFILE_STATIC int IMFS_memfile_read( |
---|
| 544 | IMFS_jnode_t *the_jnode, |
---|
| 545 | off_t start, |
---|
| 546 | unsigned char *destination, |
---|
| 547 | unsigned int length |
---|
| 548 | ) |
---|
| 549 | { |
---|
| 550 | block_p *block_ptr; |
---|
| 551 | unsigned int block; |
---|
| 552 | unsigned int my_length; |
---|
| 553 | unsigned int to_copy = 0; |
---|
| 554 | unsigned int last_byte; |
---|
| 555 | unsigned int copied; |
---|
| 556 | unsigned int start_offset; |
---|
| 557 | unsigned char *dest; |
---|
| 558 | |
---|
| 559 | dest = destination; |
---|
| 560 | |
---|
| 561 | /* |
---|
| 562 | * Perform internal consistency checks |
---|
| 563 | */ |
---|
| 564 | |
---|
| 565 | assert( the_jnode ); |
---|
| 566 | if ( !the_jnode ) |
---|
[b2709481] | 567 | rtems_set_errno_and_return_minus_one( EIO ); |
---|
[07a3253d] | 568 | |
---|
[d1941587] | 569 | assert( the_jnode->type == IMFS_MEMORY_FILE || |
---|
| 570 | the_jnode->type == IMFS_LINEAR_FILE ); |
---|
| 571 | if ( the_jnode->type != IMFS_MEMORY_FILE && |
---|
| 572 | the_jnode->type != IMFS_LINEAR_FILE ) |
---|
[b2709481] | 573 | rtems_set_errno_and_return_minus_one( EIO ); |
---|
[07a3253d] | 574 | |
---|
| 575 | /* |
---|
| 576 | * Error checks on arguments |
---|
| 577 | */ |
---|
| 578 | |
---|
| 579 | assert( dest ); |
---|
| 580 | if ( !dest ) |
---|
[b2709481] | 581 | rtems_set_errno_and_return_minus_one( EINVAL ); |
---|
[07a3253d] | 582 | |
---|
| 583 | /* |
---|
| 584 | * If there is nothing to read, then quick exit. |
---|
| 585 | */ |
---|
| 586 | |
---|
| 587 | my_length = length; |
---|
| 588 | if ( !my_length ) |
---|
[b2709481] | 589 | rtems_set_errno_and_return_minus_one( EINVAL ); |
---|
[07a3253d] | 590 | |
---|
[d1941587] | 591 | /* |
---|
| 592 | * Linear files (as created from a tar file are easier to handle |
---|
| 593 | * than block files). |
---|
| 594 | */ |
---|
| 595 | if (the_jnode->type == IMFS_LINEAR_FILE) { |
---|
| 596 | unsigned char *file_ptr; |
---|
| 597 | |
---|
| 598 | file_ptr = (unsigned char *)the_jnode->info.linearfile.direct; |
---|
| 599 | |
---|
| 600 | if (my_length > (the_jnode->info.linearfile.size - start)) |
---|
| 601 | my_length = the_jnode->info.linearfile.size - start; |
---|
| 602 | |
---|
| 603 | memcpy(dest, &file_ptr[start], my_length); |
---|
| 604 | |
---|
| 605 | IMFS_update_atime( the_jnode ); |
---|
| 606 | |
---|
| 607 | return my_length; |
---|
| 608 | } |
---|
| 609 | |
---|
[07a3253d] | 610 | /* |
---|
| 611 | * If the last byte we are supposed to read is past the end of this |
---|
| 612 | * in memory file, then shorten the length to read. |
---|
| 613 | */ |
---|
| 614 | |
---|
| 615 | last_byte = start + length; |
---|
| 616 | if ( last_byte > the_jnode->info.file.size ) |
---|
| 617 | my_length = the_jnode->info.file.size - start; |
---|
| 618 | |
---|
| 619 | copied = 0; |
---|
| 620 | |
---|
| 621 | /* |
---|
| 622 | * Three phases to the read: |
---|
| 623 | * + possibly the last part of one block |
---|
| 624 | * + all of zero of more blocks |
---|
| 625 | * + possibly the first part of one block |
---|
| 626 | */ |
---|
| 627 | |
---|
| 628 | /* |
---|
| 629 | * Phase 1: possibly the last part of one block |
---|
| 630 | */ |
---|
| 631 | |
---|
| 632 | start_offset = start % IMFS_MEMFILE_BYTES_PER_BLOCK; |
---|
| 633 | block = start / IMFS_MEMFILE_BYTES_PER_BLOCK; |
---|
| 634 | if ( start_offset ) { |
---|
| 635 | to_copy = IMFS_MEMFILE_BYTES_PER_BLOCK - start_offset; |
---|
| 636 | if ( to_copy > my_length ) |
---|
| 637 | to_copy = my_length; |
---|
| 638 | block_ptr = IMFS_memfile_get_block_pointer( the_jnode, block, 0 ); |
---|
| 639 | assert( block_ptr ); |
---|
| 640 | if ( !block_ptr ) |
---|
| 641 | return copied; |
---|
| 642 | memcpy( dest, &(*block_ptr)[ start_offset ], to_copy ); |
---|
| 643 | dest += to_copy; |
---|
| 644 | block++; |
---|
| 645 | my_length -= to_copy; |
---|
| 646 | copied += to_copy; |
---|
| 647 | } |
---|
| 648 | |
---|
| 649 | /* |
---|
| 650 | * Phase 2: all of zero of more blocks |
---|
| 651 | */ |
---|
| 652 | |
---|
| 653 | to_copy = IMFS_MEMFILE_BYTES_PER_BLOCK; |
---|
| 654 | while ( my_length >= IMFS_MEMFILE_BYTES_PER_BLOCK ) { |
---|
| 655 | block_ptr = IMFS_memfile_get_block_pointer( the_jnode, block, 0 ); |
---|
| 656 | assert( block_ptr ); |
---|
| 657 | if ( !block_ptr ) |
---|
| 658 | return copied; |
---|
| 659 | memcpy( dest, &(*block_ptr)[ 0 ], to_copy ); |
---|
| 660 | dest += to_copy; |
---|
| 661 | block++; |
---|
| 662 | my_length -= to_copy; |
---|
| 663 | copied += to_copy; |
---|
| 664 | } |
---|
| 665 | |
---|
| 666 | /* |
---|
| 667 | * Phase 3: possibly the first part of one block |
---|
| 668 | */ |
---|
| 669 | |
---|
| 670 | assert( my_length < IMFS_MEMFILE_BYTES_PER_BLOCK ); |
---|
| 671 | |
---|
| 672 | if ( my_length ) { |
---|
| 673 | block_ptr = IMFS_memfile_get_block_pointer( the_jnode, block, 0 ); |
---|
| 674 | assert( block_ptr ); |
---|
| 675 | if ( !block_ptr ) |
---|
| 676 | return copied; |
---|
| 677 | memcpy( dest, &(*block_ptr)[ 0 ], my_length ); |
---|
| 678 | copied += my_length; |
---|
| 679 | } |
---|
| 680 | |
---|
| 681 | IMFS_update_atime( the_jnode ); |
---|
| 682 | |
---|
| 683 | return copied; |
---|
| 684 | } |
---|
| 685 | |
---|
| 686 | /* |
---|
| 687 | * IMFS_memfile_write |
---|
| 688 | * |
---|
| 689 | * This routine writes the specified data buffer into the in memory |
---|
| 690 | * file pointed to by the_jnode. The file is extended as needed. |
---|
| 691 | */ |
---|
| 692 | |
---|
| 693 | MEMFILE_STATIC int IMFS_memfile_write( |
---|
| 694 | IMFS_jnode_t *the_jnode, |
---|
| 695 | off_t start, |
---|
| 696 | const unsigned char *source, |
---|
| 697 | unsigned int length |
---|
| 698 | ) |
---|
| 699 | { |
---|
| 700 | block_p *block_ptr; |
---|
| 701 | unsigned int block; |
---|
| 702 | int status; |
---|
| 703 | unsigned int my_length; |
---|
| 704 | unsigned int to_copy = 0; |
---|
| 705 | unsigned int last_byte; |
---|
| 706 | unsigned int start_offset; |
---|
| 707 | int copied; |
---|
| 708 | const unsigned char *src; |
---|
| 709 | |
---|
| 710 | src = source; |
---|
| 711 | |
---|
| 712 | /* |
---|
| 713 | * Perform internal consistency checks |
---|
| 714 | */ |
---|
| 715 | |
---|
| 716 | assert( the_jnode ); |
---|
| 717 | if ( !the_jnode ) |
---|
[b2709481] | 718 | rtems_set_errno_and_return_minus_one( EIO ); |
---|
[07a3253d] | 719 | |
---|
| 720 | assert( the_jnode->type == IMFS_MEMORY_FILE ); |
---|
| 721 | if ( the_jnode->type != IMFS_MEMORY_FILE ) |
---|
[b2709481] | 722 | rtems_set_errno_and_return_minus_one( EIO ); |
---|
[07a3253d] | 723 | |
---|
| 724 | /* |
---|
| 725 | * Error check arguments |
---|
| 726 | */ |
---|
| 727 | |
---|
| 728 | assert( source ); |
---|
| 729 | if ( !source ) |
---|
[b2709481] | 730 | rtems_set_errno_and_return_minus_one( EINVAL ); |
---|
[07a3253d] | 731 | |
---|
| 732 | |
---|
| 733 | /* |
---|
| 734 | * If there is nothing to write, then quick exit. |
---|
| 735 | */ |
---|
| 736 | |
---|
| 737 | my_length = length; |
---|
| 738 | if ( !my_length ) |
---|
[b2709481] | 739 | rtems_set_errno_and_return_minus_one( EINVAL ); |
---|
[07a3253d] | 740 | |
---|
| 741 | /* |
---|
| 742 | * If the last byte we are supposed to write is past the end of this |
---|
| 743 | * in memory file, then extend the length. |
---|
| 744 | */ |
---|
| 745 | |
---|
| 746 | last_byte = start + length; |
---|
| 747 | if ( last_byte > the_jnode->info.file.size ) { |
---|
| 748 | status = IMFS_memfile_extend( the_jnode, last_byte ); |
---|
| 749 | if ( status ) |
---|
[b2709481] | 750 | rtems_set_errno_and_return_minus_one( ENOSPC ); |
---|
[07a3253d] | 751 | } |
---|
| 752 | |
---|
| 753 | copied = 0; |
---|
| 754 | |
---|
| 755 | /* |
---|
| 756 | * Three phases to the write: |
---|
| 757 | * + possibly the last part of one block |
---|
| 758 | * + all of zero of more blocks |
---|
| 759 | * + possibly the first part of one block |
---|
| 760 | */ |
---|
| 761 | |
---|
| 762 | /* |
---|
| 763 | * Phase 1: possibly the last part of one block |
---|
| 764 | */ |
---|
| 765 | |
---|
| 766 | start_offset = start % IMFS_MEMFILE_BYTES_PER_BLOCK; |
---|
| 767 | block = start / IMFS_MEMFILE_BYTES_PER_BLOCK; |
---|
| 768 | if ( start_offset ) { |
---|
| 769 | to_copy = IMFS_MEMFILE_BYTES_PER_BLOCK - start_offset; |
---|
| 770 | if ( to_copy > my_length ) |
---|
| 771 | to_copy = my_length; |
---|
| 772 | block_ptr = IMFS_memfile_get_block_pointer( the_jnode, block, 0 ); |
---|
| 773 | assert( block_ptr ); |
---|
| 774 | if ( !block_ptr ) |
---|
| 775 | return copied; |
---|
[b10f6e1] | 776 | #if 0 |
---|
| 777 | printf( "write %d at %d in %d: %*s\n", to_copy, start_offset, block, to_copy, src ); |
---|
| 778 | #endif |
---|
[07a3253d] | 779 | memcpy( &(*block_ptr)[ start_offset ], src, to_copy ); |
---|
| 780 | src += to_copy; |
---|
| 781 | block++; |
---|
| 782 | my_length -= to_copy; |
---|
| 783 | copied += to_copy; |
---|
| 784 | } |
---|
| 785 | |
---|
| 786 | /* |
---|
| 787 | * Phase 2: all of zero of more blocks |
---|
| 788 | */ |
---|
| 789 | |
---|
| 790 | to_copy = IMFS_MEMFILE_BYTES_PER_BLOCK; |
---|
| 791 | while ( my_length >= IMFS_MEMFILE_BYTES_PER_BLOCK ) { |
---|
| 792 | block_ptr = IMFS_memfile_get_block_pointer( the_jnode, block, 0 ); |
---|
| 793 | assert( block_ptr ); |
---|
| 794 | if ( !block_ptr ) |
---|
| 795 | return copied; |
---|
[b10f6e1] | 796 | #if 0 |
---|
| 797 | printf( "write %d in %d: %*s\n", to_copy, block, to_copy, src ); |
---|
| 798 | #endif |
---|
[07a3253d] | 799 | memcpy( &(*block_ptr)[ 0 ], src, to_copy ); |
---|
| 800 | src += to_copy; |
---|
| 801 | block++; |
---|
| 802 | my_length -= to_copy; |
---|
| 803 | copied += to_copy; |
---|
| 804 | } |
---|
| 805 | |
---|
| 806 | /* |
---|
| 807 | * Phase 3: possibly the first part of one block |
---|
| 808 | */ |
---|
| 809 | |
---|
| 810 | assert( my_length < IMFS_MEMFILE_BYTES_PER_BLOCK ); |
---|
| 811 | |
---|
| 812 | to_copy = my_length; |
---|
| 813 | if ( my_length ) { |
---|
| 814 | block_ptr = IMFS_memfile_get_block_pointer( the_jnode, block, 0 ); |
---|
| 815 | assert( block_ptr ); |
---|
| 816 | if ( !block_ptr ) |
---|
| 817 | return copied; |
---|
[b10f6e1] | 818 | #if 0 |
---|
| 819 | printf( "write %d in %d: %*s\n", to_copy, block, to_copy, src ); |
---|
| 820 | #endif |
---|
[07a3253d] | 821 | memcpy( &(*block_ptr)[ 0 ], src, my_length ); |
---|
| 822 | my_length = 0; |
---|
| 823 | copied += to_copy; |
---|
| 824 | } |
---|
| 825 | |
---|
| 826 | IMFS_atime_mtime_update( the_jnode ); |
---|
| 827 | |
---|
| 828 | return copied; |
---|
| 829 | } |
---|
| 830 | |
---|
| 831 | /* |
---|
| 832 | * IMFS_memfile_get_block_pointer |
---|
| 833 | * |
---|
| 834 | * This routine looks up the block pointer associated with the given block |
---|
| 835 | * number. If that block has not been allocated and "malloc_it" is |
---|
| 836 | * TRUE, then the block is allocated. Otherwise, it is an error. |
---|
| 837 | */ |
---|
| 838 | |
---|
[b10f6e1] | 839 | #if 0 |
---|
| 840 | block_p *IMFS_memfile_get_block_pointer_DEBUG( |
---|
| 841 | IMFS_jnode_t *the_jnode, |
---|
| 842 | unsigned int block, |
---|
| 843 | int malloc_it |
---|
| 844 | ); |
---|
| 845 | |
---|
[07a3253d] | 846 | block_p *IMFS_memfile_get_block_pointer( |
---|
| 847 | IMFS_jnode_t *the_jnode, |
---|
| 848 | unsigned int block, |
---|
| 849 | int malloc_it |
---|
| 850 | ) |
---|
[b10f6e1] | 851 | { |
---|
| 852 | block_p *p; |
---|
| 853 | |
---|
| 854 | p = IMFS_memfile_get_block_pointer_DEBUG( the_jnode, block, malloc_it ); |
---|
| 855 | printf( "(%d -> %p) ", block, p ); |
---|
| 856 | return p; |
---|
| 857 | } |
---|
| 858 | |
---|
| 859 | block_p *IMFS_memfile_get_block_pointer_DEBUG( |
---|
| 860 | #else |
---|
| 861 | block_p *IMFS_memfile_get_block_pointer( |
---|
| 862 | #endif |
---|
| 863 | IMFS_jnode_t *the_jnode, |
---|
| 864 | unsigned int block, |
---|
| 865 | int malloc_it |
---|
| 866 | ) |
---|
[07a3253d] | 867 | { |
---|
| 868 | unsigned int my_block; |
---|
| 869 | IMFS_memfile_t *info; |
---|
| 870 | unsigned int singly; |
---|
| 871 | unsigned int doubly; |
---|
| 872 | unsigned int triply; |
---|
| 873 | block_p *p; |
---|
| 874 | block_p *p1; |
---|
| 875 | block_p *p2; |
---|
| 876 | |
---|
| 877 | /* |
---|
| 878 | * Perform internal consistency checks |
---|
| 879 | */ |
---|
| 880 | |
---|
| 881 | assert( the_jnode ); |
---|
| 882 | if ( !the_jnode ) |
---|
| 883 | return NULL; |
---|
| 884 | |
---|
| 885 | assert( the_jnode->type == IMFS_MEMORY_FILE ); |
---|
| 886 | if ( the_jnode->type != IMFS_MEMORY_FILE ) |
---|
| 887 | return NULL; |
---|
| 888 | |
---|
| 889 | info = &the_jnode->info.file; |
---|
| 890 | |
---|
| 891 | my_block = block; |
---|
| 892 | |
---|
| 893 | /* |
---|
| 894 | * Is the block number in the simple indirect portion? |
---|
| 895 | */ |
---|
| 896 | |
---|
| 897 | if ( my_block <= LAST_INDIRECT ) { |
---|
| 898 | #if 0 |
---|
| 899 | printf( "(s %d) ", block ); |
---|
| 900 | fflush(stdout); |
---|
| 901 | #endif |
---|
| 902 | p = info->indirect; |
---|
| 903 | |
---|
| 904 | if ( malloc_it ) { |
---|
| 905 | |
---|
| 906 | if ( !p ) { |
---|
| 907 | p = memfile_alloc_block(); |
---|
| 908 | if ( !p ) |
---|
| 909 | return 0; |
---|
| 910 | info->indirect = p; |
---|
| 911 | } |
---|
| 912 | return &info->indirect[ my_block ]; |
---|
| 913 | } |
---|
| 914 | |
---|
| 915 | if ( !p ) |
---|
| 916 | return 0; |
---|
| 917 | |
---|
| 918 | return &info->indirect[ my_block ]; |
---|
| 919 | } |
---|
| 920 | |
---|
| 921 | /* |
---|
| 922 | * Is the block number in the doubly indirect portion? |
---|
| 923 | */ |
---|
| 924 | |
---|
| 925 | if ( my_block <= LAST_DOUBLY_INDIRECT ) { |
---|
| 926 | #if 0 |
---|
| 927 | printf( "(d %d) ", block ); |
---|
| 928 | fflush(stdout); |
---|
| 929 | #endif |
---|
| 930 | |
---|
| 931 | my_block -= FIRST_DOUBLY_INDIRECT; |
---|
| 932 | |
---|
| 933 | singly = my_block % IMFS_MEMFILE_BLOCK_SLOTS; |
---|
| 934 | doubly = my_block / IMFS_MEMFILE_BLOCK_SLOTS; |
---|
| 935 | |
---|
| 936 | p = info->doubly_indirect; |
---|
| 937 | if ( malloc_it ) { |
---|
| 938 | |
---|
| 939 | if ( !p ) { |
---|
| 940 | p = memfile_alloc_block(); |
---|
| 941 | if ( !p ) |
---|
| 942 | return 0; |
---|
| 943 | info->doubly_indirect = p; |
---|
| 944 | } |
---|
| 945 | |
---|
| 946 | p1 = (block_p *)p[ doubly ]; |
---|
| 947 | if ( !p1 ) { |
---|
| 948 | p1 = memfile_alloc_block(); |
---|
| 949 | if ( !p1 ) |
---|
| 950 | return 0; |
---|
| 951 | p[ doubly ] = (block_p) p1; |
---|
| 952 | } |
---|
| 953 | |
---|
[b10f6e1] | 954 | return (block_p *)&p1[ singly ]; |
---|
[07a3253d] | 955 | } |
---|
| 956 | |
---|
| 957 | if ( !p ) |
---|
| 958 | return 0; |
---|
| 959 | |
---|
| 960 | p = (block_p *)p[ doubly ]; |
---|
| 961 | if ( !p ) |
---|
| 962 | return 0; |
---|
| 963 | |
---|
| 964 | #if 0 |
---|
| 965 | printf( "(d %d %d %d %d %p %p) ", block, my_block, doubly, |
---|
| 966 | singly, p, &p[singly] ); |
---|
| 967 | fflush(stdout); |
---|
| 968 | #endif |
---|
| 969 | return (block_p *)&p[ singly ]; |
---|
| 970 | } |
---|
| 971 | |
---|
| 972 | #if 0 |
---|
| 973 | printf( "(t %d) ", block ); |
---|
| 974 | fflush(stdout); |
---|
| 975 | #endif |
---|
| 976 | /* |
---|
| 977 | * Is the block number in the triply indirect portion? |
---|
| 978 | */ |
---|
| 979 | |
---|
| 980 | if ( my_block <= LAST_TRIPLY_INDIRECT ) { |
---|
| 981 | my_block -= FIRST_TRIPLY_INDIRECT; |
---|
| 982 | |
---|
| 983 | singly = my_block % IMFS_MEMFILE_BLOCK_SLOTS; |
---|
| 984 | doubly = my_block / IMFS_MEMFILE_BLOCK_SLOTS; |
---|
| 985 | triply = doubly / IMFS_MEMFILE_BLOCK_SLOTS; |
---|
| 986 | doubly %= IMFS_MEMFILE_BLOCK_SLOTS; |
---|
| 987 | |
---|
| 988 | p = info->triply_indirect; |
---|
| 989 | |
---|
| 990 | if ( malloc_it ) { |
---|
| 991 | if ( !p ) { |
---|
| 992 | p = memfile_alloc_block(); |
---|
| 993 | if ( !p ) |
---|
| 994 | return 0; |
---|
| 995 | info->triply_indirect = p; |
---|
| 996 | } |
---|
| 997 | |
---|
| 998 | p1 = (block_p *) p[ triply ]; |
---|
| 999 | if ( !p1 ) { |
---|
| 1000 | p1 = memfile_alloc_block(); |
---|
| 1001 | if ( !p1 ) |
---|
| 1002 | return 0; |
---|
| 1003 | p[ triply ] = (block_p) p1; |
---|
| 1004 | } |
---|
| 1005 | |
---|
| 1006 | p2 = (block_p *)p1[ doubly ]; |
---|
| 1007 | if ( !p2 ) { |
---|
| 1008 | p2 = memfile_alloc_block(); |
---|
| 1009 | if ( !p2 ) |
---|
| 1010 | return 0; |
---|
| 1011 | p1[ doubly ] = (block_p) p2; |
---|
| 1012 | } |
---|
| 1013 | return (block_p *)&p2[ singly ]; |
---|
| 1014 | } |
---|
| 1015 | |
---|
| 1016 | if ( !p ) |
---|
| 1017 | return 0; |
---|
| 1018 | |
---|
| 1019 | #if 0 |
---|
| 1020 | printf( "(t %d %d %d %d %d) ", block, my_block, triply, doubly, singly ); |
---|
| 1021 | fflush(stdout); |
---|
| 1022 | #endif |
---|
| 1023 | p1 = (block_p *) p[ triply ]; |
---|
| 1024 | if ( !p1 ) |
---|
| 1025 | return 0; |
---|
| 1026 | |
---|
| 1027 | p2 = (block_p *)p1[ doubly ]; |
---|
| 1028 | if ( !p ) |
---|
| 1029 | return 0; |
---|
| 1030 | |
---|
| 1031 | return (block_p *)&p2[ singly ]; |
---|
| 1032 | } |
---|
| 1033 | |
---|
| 1034 | /* |
---|
| 1035 | * This means the requested block number is out of range. |
---|
| 1036 | */ |
---|
| 1037 | |
---|
| 1038 | return 0; |
---|
| 1039 | } |
---|
| 1040 | |
---|
| 1041 | /* |
---|
| 1042 | * memfile_alloc_block |
---|
| 1043 | * |
---|
| 1044 | * Allocate a block for an in-memory file. |
---|
| 1045 | */ |
---|
| 1046 | |
---|
| 1047 | int memfile_blocks_allocated = 0; |
---|
| 1048 | |
---|
| 1049 | void *memfile_alloc_block(void) |
---|
| 1050 | { |
---|
| 1051 | void *memory; |
---|
| 1052 | |
---|
| 1053 | memory = (void *)calloc(1, IMFS_MEMFILE_BYTES_PER_BLOCK); |
---|
| 1054 | if ( memory ) |
---|
| 1055 | memfile_blocks_allocated++; |
---|
| 1056 | |
---|
| 1057 | return memory; |
---|
| 1058 | } |
---|
| 1059 | |
---|
| 1060 | /* |
---|
[b10f6e1] | 1061 | * memfile_free_block |
---|
[07a3253d] | 1062 | * |
---|
| 1063 | * Free a block from an in-memory file. |
---|
| 1064 | */ |
---|
| 1065 | |
---|
| 1066 | void memfile_free_block( |
---|
| 1067 | void *memory |
---|
| 1068 | ) |
---|
| 1069 | { |
---|
| 1070 | #if 0 |
---|
| 1071 | printf( "(d %p) ", memory ); |
---|
| 1072 | fflush(stdout); |
---|
| 1073 | #endif |
---|
| 1074 | free(memory); |
---|
| 1075 | memfile_blocks_allocated--; |
---|
| 1076 | } |
---|
| 1077 | |
---|
[b568ccb] | 1078 | |
---|
| 1079 | /* |
---|
| 1080 | * memfile_rmnod |
---|
| 1081 | * |
---|
| 1082 | * This routine is available from the optable to remove a node |
---|
| 1083 | * from the IMFS file system. |
---|
| 1084 | */ |
---|
| 1085 | |
---|
| 1086 | int memfile_rmnod( |
---|
| 1087 | rtems_filesystem_location_info_t *pathloc /* IN */ |
---|
| 1088 | ) |
---|
| 1089 | { |
---|
| 1090 | IMFS_jnode_t *the_jnode; |
---|
| 1091 | |
---|
| 1092 | the_jnode = (IMFS_jnode_t *) pathloc->node_access; |
---|
| 1093 | |
---|
| 1094 | /* |
---|
| 1095 | * Take the node out of the parent's chain that contains this node |
---|
| 1096 | */ |
---|
| 1097 | |
---|
| 1098 | if ( the_jnode->Parent != NULL ) { |
---|
| 1099 | Chain_Extract( (Chain_Node *) the_jnode ); |
---|
| 1100 | the_jnode->Parent = NULL; |
---|
| 1101 | } |
---|
| 1102 | |
---|
| 1103 | /* |
---|
| 1104 | * Decrement the link counter and see if we can free the space. |
---|
| 1105 | */ |
---|
| 1106 | |
---|
| 1107 | the_jnode->st_nlink--; |
---|
| 1108 | IMFS_update_ctime( the_jnode ); |
---|
| 1109 | |
---|
| 1110 | /* |
---|
| 1111 | * The file cannot be open and the link must be less than 1 to free. |
---|
| 1112 | */ |
---|
| 1113 | |
---|
| 1114 | if ( !rtems_libio_is_file_open( the_jnode ) && (the_jnode->st_nlink < 1) ) { |
---|
| 1115 | |
---|
| 1116 | /* |
---|
| 1117 | * Is the rtems_filesystem_current is this node? |
---|
| 1118 | */ |
---|
| 1119 | |
---|
| 1120 | if ( rtems_filesystem_current.node_access == pathloc->node_access ) |
---|
| 1121 | rtems_filesystem_current.node_access = NULL; |
---|
| 1122 | |
---|
| 1123 | /* |
---|
| 1124 | * Free memory associated with a memory file. |
---|
| 1125 | */ |
---|
[d1941587] | 1126 | if (the_jnode->type != IMFS_LINEAR_FILE) |
---|
| 1127 | IMFS_memfile_remove( the_jnode ); |
---|
[b568ccb] | 1128 | |
---|
| 1129 | free( the_jnode ); |
---|
| 1130 | } |
---|
| 1131 | |
---|
| 1132 | return 0; |
---|
| 1133 | |
---|
| 1134 | } |
---|
| 1135 | |
---|
| 1136 | |
---|