📄 fat32.lst
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241 2 ((Byte*)&bpb_rsvd_sec_cnt)[0] = Hard_read_byte();
242 2 /* number of FATs */
243 2 bpb_num_fat = Hard_read_byte();
244 2 if (bpb_num_fat == 2)
245 2 fat_2_is_present = TRUE;
246 2 else
247 2 fat_2_is_present = FALSE;
248 2
249 2 /* read number of dir entries*/
250 2 ((Byte*)&bpb_root_ent_count)[3] = Hard_read_byte();
251 2 ((Byte*)&bpb_root_ent_count)[2] = Hard_read_byte();
252 2
253 2 /* read number of sector in partition (<32Mb) */
254 2 ((Byte*)&fat_nb_sector)[3] = Hard_read_byte();
255 2 ((Byte*)&fat_nb_sector)[2] = Hard_read_byte();
256 2 ((Byte*)&fat_nb_sector)[1] = 0x00;
257 2 ((Byte*)&fat_nb_sector)[0] = 0x00;
258 2 Hard_read_byte();
259 2 Hard_read_byte(); /* FAT size for FAT12/16 */
260 2 Hard_read_byte();
261 2
262 2 Hard_read_byte();
263 2 Hard_read_byte();
264 2 Hard_read_byte();
265 2 Hard_read_byte();
266 2 Hard_read_byte();
267 2 Hard_read_byte();
268 2 Hard_read_byte();
269 2 Hard_read_byte();
270 2
271 2 /* read number of sector in partition (>32Mb) */
272 2 ((Byte*)&fat_nb_sector)[3] += Hard_read_byte();
273 2 ((Byte*)&fat_nb_sector)[2] += Hard_read_byte();
274 2 ((Byte*)&fat_nb_sector)[1] += Hard_read_byte();
275 2 ((Byte*)&fat_nb_sector)[0] += Hard_read_byte();
276 2
277 2 fat_is_fat16 = FALSE;
278 2 fat_is_fat32 = FALSE;
279 2
280 2 fat_ptr_data = (bpb_root_ent_count * DIR_SIZE) / SECTOR_SIZE;
281 2
282 2 /* Here start the structure for FAT32 */
283 2 /* Offset 36 : 32 bits size of fat */
284 2 ((Byte*)&fat_fat_size)[3] = Hard_read_byte();
285 2 ((Byte*)&fat_fat_size)[2] = Hard_read_byte();
286 2 ((Byte*)&fat_fat_size)[1] = Hard_read_byte();
287 2 ((Byte*)&fat_fat_size)[0] = Hard_read_byte();
288 2
289 2 tot_sect = fat_nb_sector - (Uint32)(((Uint32)(bpb_rsvd_sec_cnt) + (Uint32)((bpb_num_fat * (Uint32)(fat
-_fat_size))) + fat_ptr_data));
290 2 fat_count_of_clusters = tot_sect / fat_cluster_size;
291 2
292 2 /* Offset 40 : ExtFlags */
293 2 Hard_read_byte();
294 2 Hard_read_byte();
295 2 /* Offset 42 : FS Version */
296 2 Hard_read_byte();
297 2 Hard_read_byte();
298 2 /* Offset 44 : Root Cluster */
299 2 ((Byte*)&fat_rootclus_fat32)[3] = Hard_read_byte();
300 2 ((Byte*)&fat_rootclus_fat32)[2] = Hard_read_byte();
301 2 ((Byte*)&fat_rootclus_fat32)[1] = Hard_read_byte();
C51 COMPILER V6.20c FAT32 10/19/2004 12:22:16 PAGE 6
302 2 ((Byte*)&fat_rootclus_fat32)[0] = Hard_read_byte();
303 2
304 2 fat_ptr_fats += bpb_rsvd_sec_cnt;
305 2 fat_ptr_data = fat_ptr_fats + (bpb_num_fat * fat_fat_size);
306 2
307 2 /* Offset 48 : FS Info */
308 2 /* Offset 50 : Backup Boot Sector */
309 2 /* Offset 52 : Reserved */
310 2 /* Offset 64 - 89 : Data */
311 2 /* Offset 90 : 510 : Free */
312 2 for (i = 231; i != 0; i--)
313 2 {
314 3 Hard_read_byte();
315 3 Hard_read_byte();
316 3 }
317 2 /* check partition signature */
318 2 if ((Hard_read_byte() != LOW(BR_SIGNATURE)) &&
319 2 (Hard_read_byte() != HIGH(BR_SIGNATURE)))
320 2 {
321 3 Hard_read_close(); /* close physical read */
322 3 return KO;
323 3 }
324 2 Hard_read_close(); /* close physical read */
325 2 return OK;
326 2 }
327 1 else
328 1 { /* low level error */
329 2 return KO;
330 2 }
331 1 }
332
333 #define UPLOAD 0
334 #define DOWNLOAD 1
335 #define FETCH_NEXT 0
336 #define FETCH_PREV 1
337
338 /*F**************************************************************************
339 * NAME: fat_calc_cluster
340 *----------------------------------------------------------------------------
341 * PARAMS:
342 *
343 *
344 * return:
345 *----------------------------------------------------------------------------
346 * PURPOSE:
347 * Calculate fat_dir_current_sect and update directory variable from the
348 * value of fat_dir_current_offs.
349 *----------------------------------------------------------------------------
350 * EXAMPLE:
351 *----------------------------------------------------------------------------
352 * NOTE:
353 *
354 *----------------------------------------------------------------------------
355 * REQUIREMENTS:
356 *
357 *****************************************************************************/
358 void fat_calc_cluster(void)
359 {
360 1 Uint32 i;
361 1 fat_dchain_index = 0;
362 1 fat_dchain_nb_clust = 0;
363 1 for (i = (fat_dir_current_offs / SECTOR_SIZE / fat_cluster_size) + 1; i != 0; i--)
C51 COMPILER V6.20c FAT32 10/19/2004 12:22:16 PAGE 7
364 1 {
365 2 if (dclusters[fat_dchain_index].number == fat_dchain_nb_clust)
366 2 { /* new fragment */
367 3 fat_dchain_index++;
368 3 fat_dchain_nb_clust = 1;
369 3 }
370 2 else
371 2 { /* no new fragment */
372 3 fat_dchain_nb_clust++;
373 3 }
374 2 }
375 1 i = fat_dir_current_offs / SECTOR_SIZE;
376 1 fat_dir_current_sect = (((Uint32)(dclusters[fat_dchain_index].cluster + fat_dchain_nb_clust - 1) *
377 1 fat_cluster_size)
378 1 + fat_ptr_data + (i % fat_cluster_size));
379 1
380 1 if ((fat_dclust_byte_count == 0)/* && (fat_dchain_index == 0)*/) /* If we are at the beginning of a
-directory */
381 1 if (fat_dchain_nb_clust == 1)
382 1 fat_dchain_nb_clust = 0;
383 1 }
384
385
386 /*F**************************************************************************
387 * NAME: fat_clear_dir_info
388 *----------------------------------------------------------------------------
389 * PARAMS:
390 *
391 *
392 * return:
393 *----------------------------------------------------------------------------
394 * PURPOSE:
395 * Reset directory chain cluster value
396 *----------------------------------------------------------------------------
397 * EXAMPLE:
398 *----------------------------------------------------------------------------
399 * NOTE:
400 *
401 *----------------------------------------------------------------------------
402 * REQUIREMENTS:
403 *
404 *****************************************************************************/
405 void fat_clear_dir_info(void)
406 {
407 1 fat_dchain_nb_clust = 0; /* position of a cluster for selected chain idx */
408 1 fat_dchain_index = 0; /* chain index position */
409 1 fat_dclust_byte_count = 0; /* byte position inside a directory cluster */
410 1 fat_dir_current_offs = 0; /* general offset from the start of a directory */
411 1 }
412
413 /*F**************************************************************************
414 * NAME: fat_up_down_load_sector
415 *----------------------------------------------------------------------------
416 * PARAMS:
417 * - sector address to load/download
418 * - bit to indicate if it's a download or an upload
419 *
420 * return:
421 *----------------------------------------------------------------------------
422 * PURPOSE:
423 * Download or upload a sector of 512b
424 *----------------------------------------------------------------------------
C51 COMPILER V6.20c FAT32 10/19/2004 12:22:16 PAGE 8
425 * EXAMPLE:
426 *----------------------------------------------------------------------------
427 * NOTE:
428 *
429 *----------------------------------------------------------------------------
430 * REQUIREMENTS:
431 *
432 *****************************************************************************/
433 void fat_up_down_load_sector(Uint32 sector, bit up_down)
434 {
435 1 if (up_down == UPLOAD)
436 1 {
437 2 Hard_read_open(sector);
438 2 Hard_load_sector();
439 2 Hard_read_close();
440 2 }
441 1 else
442 1 {
443 2 Hard_write_open(sector);
444 2 Hard_download_sector();
445 2 Hard_write_close();
446 2 }
447 1 }
448
449 /*F**************************************************************************
450 * NAME: fat_get_dir_file_list
451 *----------------------------------------------------------------------------
452 * PARAMS:
453 * id: file extension to select
454 *
455 * return:
456 *----------------------------------------------------------------------------
457 * PURPOSE:
458 * Give information about the directory :
459 * - total number of entries
460 * - number of deleted entries
461 * - number of filtered entries (filter is done by checking id value)
462 * - total number of clusters used by the directory
463 *----------------------------------------------------------------------------
464 * EXAMPLE:
465 *
466 *----------------------------------------------------------------------------
467 * NOTE:
468 *
469 *----------------------------------------------------------------------------
470 * REQUIREMENTS:
471 *
472 *****************************************************************************/
473 void fat_get_dir_file_list (Byte id)
474 {
475 1 Byte i;
476 1 bit exit = FALSE;
477 1
478 1 current_ext = id; /* save current extension */
479 1 fat_last_dir_cluster_full = FALSE; /* reset flag for full cluster */
480 1 fat_no_entries_free = FALSE; /* reset flag for presence of free entries inside a directory
-cluster */
481 1 fat_dir_list_last = 0; /* last filtered directory entry */
482 1 fat_dir_start_sect = fat_dir_current_sect;/* set fat_dir_start_sect (use by fat_dseek()) */
483 1 fat_nb_deleted_entries = 0; /* reset the number of entries that is marker as deleted */
484 1 fat_nb_total_entries = 0; /* reset the number of total entries in the directory */
485 1 fat_total_clusters = 0; /* reset the total number of clusters for a directory */
C51 COMPILER V6.20c FAT32 10/19/2004 12:22:16 PAGE 9
486 1
487 1 for (i = 0; i <= fat_last_dclust_index; i++)
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