From: Rob Clark Date: Sat, 9 Sep 2017 17:15:54 +0000 (-0400) Subject: fat/fs: convert to directory iterators X-Git-Tag: v2017.11-rc1~102 X-Git-Url: https://git.librecmc.org/?a=commitdiff_plain;h=8eafae209c35932d9a6560809c55ee4641534236;p=oweals%2Fu-boot.git fat/fs: convert to directory iterators And drop a whole lot of ugly code! Signed-off-by: Rob Clark Reviewed-by: Łukasz Majewski Reviewed-by: Simon Glass --- diff --git a/fs/fat/fat.c b/fs/fat/fat.c index ee2bbe38f1..bbba7947ee 100644 --- a/fs/fat/fat.c +++ b/fs/fat/fat.c @@ -118,22 +118,6 @@ int fat_register_device(struct blk_desc *dev_desc, int part_no) return fat_set_blk_dev(dev_desc, &info); } -/* - * Get the first occurence of a directory delimiter ('/' or '\') in a string. - * Return index into string if found, -1 otherwise. - */ -static int dirdelim(char *str) -{ - char *start = str; - - while (*str != '\0') { - if (ISDIRDELIM(*str)) - return str - start; - str++; - } - return -1; -} - /* * Extract zero terminated short name from a directory entry. */ @@ -468,95 +452,6 @@ static int slot2str(dir_slot *slotptr, char *l_name, int *idx) return 0; } -/* - * Extract the full long filename starting at 'retdent' (which is really - * a slot) into 'l_name'. If successful also copy the real directory entry - * into 'retdent' - * Return 0 on success, -1 otherwise. - */ -static int -get_vfatname(fsdata *mydata, int curclust, __u8 *cluster, - dir_entry *retdent, char *l_name) -{ - dir_entry *realdent; - dir_slot *slotptr = (dir_slot *)retdent; - __u8 *buflimit = cluster + mydata->sect_size * ((curclust == 0) ? - PREFETCH_BLOCKS : - mydata->clust_size); - __u8 counter = (slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff; - int idx = 0; - - if (counter > VFAT_MAXSEQ) { - debug("Error: VFAT name is too long\n"); - return -1; - } - - while ((__u8 *)slotptr < buflimit) { - if (counter == 0) - break; - if (((slotptr->id & ~LAST_LONG_ENTRY_MASK) & 0xff) != counter) - return -1; - slotptr++; - counter--; - } - - if ((__u8 *)slotptr >= buflimit) { - dir_slot *slotptr2; - - if (curclust == 0) - return -1; - curclust = get_fatent(mydata, curclust); - if (CHECK_CLUST(curclust, mydata->fatsize)) { - debug("curclust: 0x%x\n", curclust); - printf("Invalid FAT entry\n"); - return -1; - } - - if (get_cluster(mydata, curclust, get_contents_vfatname_block, - mydata->clust_size * mydata->sect_size) != 0) { - debug("Error: reading directory block\n"); - return -1; - } - - slotptr2 = (dir_slot *)get_contents_vfatname_block; - while (counter > 0) { - if (((slotptr2->id & ~LAST_LONG_ENTRY_MASK) - & 0xff) != counter) - return -1; - slotptr2++; - counter--; - } - - /* Save the real directory entry */ - realdent = (dir_entry *)slotptr2; - while ((__u8 *)slotptr2 > get_contents_vfatname_block) { - slotptr2--; - slot2str(slotptr2, l_name, &idx); - } - } else { - /* Save the real directory entry */ - realdent = (dir_entry *)slotptr; - } - - do { - slotptr--; - if (slot2str(slotptr, l_name, &idx)) - break; - } while (!(slotptr->id & LAST_LONG_ENTRY_MASK)); - - l_name[idx] = '\0'; - if (*l_name == DELETED_FLAG) - *l_name = '\0'; - else if (*l_name == aRING) - *l_name = DELETED_FLAG; - downcase(l_name); - - /* Return the real directory entry */ - memcpy(retdent, realdent, sizeof(dir_entry)); - - return 0; -} - /* Calculate short name checksum */ static __u8 mkcksum(const char name[8], const char ext[3]) { @@ -573,169 +468,13 @@ static __u8 mkcksum(const char name[8], const char ext[3]) } /* - * Get the directory entry associated with 'filename' from the directory - * starting at 'startsect' + * TODO these should go away once fat_write is reworked to use the + * directory iterator */ __u8 get_dentfromdir_block[MAX_CLUSTSIZE] __aligned(ARCH_DMA_MINALIGN); - -static dir_entry *get_dentfromdir(fsdata *mydata, int startsect, - char *filename, dir_entry *retdent, - int dols) -{ - __u16 prevcksum = 0xffff; - __u32 curclust = START(retdent); - int files = 0, dirs = 0; - - debug("get_dentfromdir: %s\n", filename); - - while (1) { - dir_entry *dentptr; - - int i; - - if (get_cluster(mydata, curclust, get_dentfromdir_block, - mydata->clust_size * mydata->sect_size) != 0) { - debug("Error: reading directory block\n"); - return NULL; - } - - dentptr = (dir_entry *)get_dentfromdir_block; - - for (i = 0; i < DIRENTSPERCLUST; i++) { - char s_name[14], l_name[VFAT_MAXLEN_BYTES]; - - l_name[0] = '\0'; - if (dentptr->name[0] == DELETED_FLAG) { - dentptr++; - continue; - } - if ((dentptr->attr & ATTR_VOLUME)) { - if (vfat_enabled && - (dentptr->attr & ATTR_VFAT) == ATTR_VFAT && - (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) { - prevcksum = ((dir_slot *)dentptr)->alias_checksum; - get_vfatname(mydata, curclust, - get_dentfromdir_block, - dentptr, l_name); - if (dols) { - int isdir; - char dirc; - int doit = 0; - - isdir = (dentptr->attr & ATTR_DIR); - - if (isdir) { - dirs++; - dirc = '/'; - doit = 1; - } else { - dirc = ' '; - if (l_name[0] != 0) { - files++; - doit = 1; - } - } - if (doit) { - if (dirc == ' ') { - printf(" %8u %s%c\n", - FAT2CPU32(dentptr->size), - l_name, - dirc); - } else { - printf(" %s%c\n", - l_name, - dirc); - } - } - dentptr++; - continue; - } - debug("vfatname: |%s|\n", l_name); - } else { - /* Volume label or VFAT entry */ - dentptr++; - continue; - } - } - if (dentptr->name[0] == 0) { - if (dols) { - printf("\n%d file(s), %d dir(s)\n\n", - files, dirs); - } - debug("Dentname == NULL - %d\n", i); - return NULL; - } - if (vfat_enabled) { - __u8 csum = mkcksum(dentptr->name, dentptr->ext); - if (dols && csum == prevcksum) { - prevcksum = 0xffff; - dentptr++; - continue; - } - } - - get_name(dentptr, s_name); - if (dols) { - int isdir = (dentptr->attr & ATTR_DIR); - char dirc; - int doit = 0; - - if (isdir) { - dirs++; - dirc = '/'; - doit = 1; - } else { - dirc = ' '; - if (s_name[0] != 0) { - files++; - doit = 1; - } - } - - if (doit) { - if (dirc == ' ') { - printf(" %8u %s%c\n", - FAT2CPU32(dentptr->size), - s_name, dirc); - } else { - printf(" %s%c\n", - s_name, dirc); - } - } - - dentptr++; - continue; - } - - if (strcmp(filename, s_name) - && strcmp(filename, l_name)) { - debug("Mismatch: |%s|%s|\n", s_name, l_name); - dentptr++; - continue; - } - - memcpy(retdent, dentptr, sizeof(dir_entry)); - - debug("DentName: %s", s_name); - debug(", start: 0x%x", START(dentptr)); - debug(", size: 0x%x %s\n", - FAT2CPU32(dentptr->size), - (dentptr->attr & ATTR_DIR) ? "(DIR)" : ""); - - return retdent; - } - - curclust = get_fatent(mydata, curclust); - if (CHECK_CLUST(curclust, mydata->fatsize)) { - debug("curclust: 0x%x\n", curclust); - printf("Invalid FAT entry\n"); - return NULL; - } - } - - return NULL; -} +__u8 do_fat_read_at_block[MAX_CLUSTSIZE] + __aligned(ARCH_DMA_MINALIGN); /* * Read boot sector and volume info from a FAT filesystem @@ -879,374 +618,6 @@ static int get_fs_info(fsdata *mydata) return 0; } -__u8 do_fat_read_at_block[MAX_CLUSTSIZE] - __aligned(ARCH_DMA_MINALIGN); - -int do_fat_read_at(const char *filename, loff_t pos, void *buffer, - loff_t maxsize, int dols, int dogetsize, loff_t *size) -{ - char fnamecopy[2048]; - fsdata datablock; - fsdata *mydata = &datablock; - dir_entry *dentptr = NULL; - __u16 prevcksum = 0xffff; - char *subname = ""; - __u32 cursect; - int idx, isdir = 0; - int files = 0, dirs = 0; - int ret = -1; - int firsttime; - __u32 root_cluster = 0; - __u32 read_blk; - int rootdir_size = 0; - int buffer_blk_cnt; - int do_read; - __u8 *dir_ptr; - - if (get_fs_info(mydata)) - return -1; - - cursect = mydata->rootdir_sect; - - /* "cwd" is always the root... */ - while (ISDIRDELIM(*filename)) - filename++; - - /* Make a copy of the filename and convert it to lowercase */ - strcpy(fnamecopy, filename); - downcase(fnamecopy); - -root_reparse: - if (*fnamecopy == '\0') { - if (!dols) - goto exit; - - dols = LS_ROOT; - } else if ((idx = dirdelim(fnamecopy)) >= 0) { - isdir = 1; - fnamecopy[idx] = '\0'; - subname = fnamecopy + idx + 1; - - /* Handle multiple delimiters */ - while (ISDIRDELIM(*subname)) - subname++; - } else if (dols) { - isdir = 1; - } - - buffer_blk_cnt = 0; - firsttime = 1; - while (1) { - int i; - - if (mydata->fatsize == 32 || firsttime) { - dir_ptr = do_fat_read_at_block; - firsttime = 0; - } else { - /** - * FAT16 sector buffer modification: - * Each loop, the second buffered block is moved to - * the buffer begin, and two next sectors are read - * next to the previously moved one. So the sector - * buffer keeps always 3 sectors for fat16. - * And the current sector is the buffer second sector - * beside the "firsttime" read, when it is the first one. - * - * PREFETCH_BLOCKS is 2 for FAT16 == loop[0:1] - * n = computed root dir sector - * loop | cursect-1 | cursect | cursect+1 | - * 0 | sector n+0 | sector n+1 | none | - * 1 | none | sector n+0 | sector n+1 | - * 0 | sector n+1 | sector n+2 | sector n+3 | - * 1 | sector n+3 | ... - */ - dir_ptr = (do_fat_read_at_block + mydata->sect_size); - memcpy(do_fat_read_at_block, dir_ptr, mydata->sect_size); - } - - do_read = 1; - - if (mydata->fatsize == 32 && buffer_blk_cnt) - do_read = 0; - - if (do_read) { - read_blk = (mydata->fatsize == 32) ? - mydata->clust_size : PREFETCH_BLOCKS; - - debug("FAT read(sect=%d, cnt:%d), clust_size=%d, DIRENTSPERBLOCK=%zd\n", - cursect, read_blk, mydata->clust_size, DIRENTSPERBLOCK); - - if (disk_read(cursect, read_blk, dir_ptr) < 0) { - debug("Error: reading rootdir block\n"); - goto exit; - } - - dentptr = (dir_entry *)dir_ptr; - } - - for (i = 0; i < DIRENTSPERBLOCK; i++) { - char s_name[14], l_name[VFAT_MAXLEN_BYTES]; - __u8 csum; - - l_name[0] = '\0'; - if (dentptr->name[0] == DELETED_FLAG) { - dentptr++; - continue; - } - - if (vfat_enabled) - csum = mkcksum(dentptr->name, dentptr->ext); - - if (dentptr->attr & ATTR_VOLUME) { - if (vfat_enabled && - (dentptr->attr & ATTR_VFAT) == ATTR_VFAT && - (dentptr->name[0] & LAST_LONG_ENTRY_MASK)) { - prevcksum = - ((dir_slot *)dentptr)->alias_checksum; - - get_vfatname(mydata, - root_cluster, - dir_ptr, - dentptr, l_name); - - if (dols == LS_ROOT) { - char dirc; - int doit = 0; - int isdir = - (dentptr->attr & ATTR_DIR); - - if (isdir) { - dirs++; - dirc = '/'; - doit = 1; - } else { - dirc = ' '; - if (l_name[0] != 0) { - files++; - doit = 1; - } - } - if (doit) { - if (dirc == ' ') { - printf(" %8u %s%c\n", - FAT2CPU32(dentptr->size), - l_name, - dirc); - } else { - printf(" %s%c\n", - l_name, - dirc); - } - } - dentptr++; - continue; - } - debug("Rootvfatname: |%s|\n", - l_name); - } else { - /* Volume label or VFAT entry */ - dentptr++; - continue; - } - } else if (dentptr->name[0] == 0) { - debug("RootDentname == NULL - %d\n", i); - if (dols == LS_ROOT) { - printf("\n%d file(s), %d dir(s)\n\n", - files, dirs); - ret = 0; - } - goto exit; - } - else if (vfat_enabled && - dols == LS_ROOT && csum == prevcksum) { - prevcksum = 0xffff; - dentptr++; - continue; - } - - get_name(dentptr, s_name); - - if (dols == LS_ROOT) { - int isdir = (dentptr->attr & ATTR_DIR); - char dirc; - int doit = 0; - - if (isdir) { - dirc = '/'; - if (s_name[0] != 0) { - dirs++; - doit = 1; - } - } else { - dirc = ' '; - if (s_name[0] != 0) { - files++; - doit = 1; - } - } - if (doit) { - if (dirc == ' ') { - printf(" %8u %s%c\n", - FAT2CPU32(dentptr->size), - s_name, dirc); - } else { - printf(" %s%c\n", - s_name, dirc); - } - } - dentptr++; - continue; - } - - if (strcmp(fnamecopy, s_name) - && strcmp(fnamecopy, l_name)) { - debug("RootMismatch: |%s|%s|\n", s_name, - l_name); - dentptr++; - continue; - } - - if (isdir && !(dentptr->attr & ATTR_DIR)) - goto exit; - - debug("RootName: %s", s_name); - debug(", start: 0x%x", START(dentptr)); - debug(", size: 0x%x %s\n", - FAT2CPU32(dentptr->size), - isdir ? "(DIR)" : ""); - - goto rootdir_done; /* We got a match */ - } - debug("END LOOP: buffer_blk_cnt=%d clust_size=%d\n", buffer_blk_cnt, - mydata->clust_size); - - /* - * On FAT32 we must fetch the FAT entries for the next - * root directory clusters when a cluster has been - * completely processed. - */ - ++buffer_blk_cnt; - int rootdir_end = 0; - if (mydata->fatsize == 32) { - if (buffer_blk_cnt == mydata->clust_size) { - int nxtsect = 0; - int nxt_clust = 0; - - nxt_clust = get_fatent(mydata, root_cluster); - rootdir_end = CHECK_CLUST(nxt_clust, 32); - - nxtsect = mydata->data_begin + - (nxt_clust * mydata->clust_size); - - root_cluster = nxt_clust; - - cursect = nxtsect; - buffer_blk_cnt = 0; - } - } else { - if (buffer_blk_cnt == PREFETCH_BLOCKS) - buffer_blk_cnt = 0; - - rootdir_end = (++cursect - mydata->rootdir_sect >= - rootdir_size); - } - - /* If end of rootdir reached */ - if (rootdir_end) { - if (dols == LS_ROOT) { - printf("\n%d file(s), %d dir(s)\n\n", - files, dirs); - *size = 0; - } - goto exit; - } - } -rootdir_done: - - firsttime = 1; - - while (isdir) { - int startsect = mydata->data_begin - + START(dentptr) * mydata->clust_size; - dir_entry dent; - char *nextname = NULL; - - dent = *dentptr; - dentptr = &dent; - - idx = dirdelim(subname); - - if (idx >= 0) { - subname[idx] = '\0'; - nextname = subname + idx + 1; - /* Handle multiple delimiters */ - while (ISDIRDELIM(*nextname)) - nextname++; - if (dols && *nextname == '\0') - firsttime = 0; - } else { - if (dols && firsttime) { - firsttime = 0; - } else { - isdir = 0; - } - } - - if (get_dentfromdir(mydata, startsect, subname, dentptr, - isdir ? 0 : dols) == NULL) { - if (dols && !isdir) - *size = 0; - goto exit; - } - - if (isdir && !(dentptr->attr & ATTR_DIR)) - goto exit; - - /* - * If we are looking for a directory, and found a directory - * type entry, and the entry is for the root directory (as - * denoted by a cluster number of 0), jump back to the start - * of the function, since at least on FAT12/16, the root dir - * lives in a hard-coded location and needs special handling - * to parse, rather than simply following the cluster linked - * list in the FAT, like other directories. - */ - if (isdir && (dentptr->attr & ATTR_DIR) && !START(dentptr)) { - /* - * Modify the filename to remove the prefix that gets - * back to the root directory, so the initial root dir - * parsing code can continue from where we are without - * confusion. - */ - strcpy(fnamecopy, nextname ?: ""); - /* - * Set up state the same way as the function does when - * first started. This is required for the root dir - * parsing code operates in its expected environment. - */ - subname = ""; - cursect = mydata->rootdir_sect; - isdir = 0; - goto root_reparse; - } - - if (idx >= 0) - subname = nextname; - } - - if (dogetsize) { - *size = FAT2CPU32(dentptr->size); - ret = 0; - } else { - ret = get_contents(mydata, dentptr, pos, buffer, maxsize, size); - } - debug("Size: %u, got: %llu\n", FAT2CPU32(dentptr->size), *size); - -exit: - free(mydata->fatbuf); - return ret; -} - /* * Directory iterator, to simplify filesystem traversal @@ -1595,12 +966,6 @@ static int fat_itr_resolve(fat_itr *itr, const char *path, unsigned type) return -ENOENT; } -int do_fat_read(const char *filename, void *buffer, loff_t maxsize, int dols, - loff_t *actread) -{ - return do_fat_read_at(filename, 0, buffer, maxsize, dols, 0, actread); -} - int file_fat_detectfs(void) { boot_sector bs; @@ -1665,31 +1030,96 @@ int file_fat_detectfs(void) int file_fat_ls(const char *dir) { - loff_t size; + fsdata fsdata; + fat_itr itrblock, *itr = &itrblock; + int files = 0, dirs = 0; + int ret; + + ret = fat_itr_root(itr, &fsdata); + if (ret) + return ret; + + ret = fat_itr_resolve(itr, dir, TYPE_DIR); + if (ret) + return ret; + + while (fat_itr_next(itr)) { + if (fat_itr_isdir(itr)) { + printf(" %s/\n", itr->name); + dirs++; + } else { + printf(" %8u %s\n", + FAT2CPU32(itr->dent->size), + itr->name); + files++; + } + } - return do_fat_read(dir, NULL, 0, LS_YES, &size); + printf("\n%d file(s), %d dir(s)\n\n", files, dirs); + + return 0; } int fat_exists(const char *filename) { + fsdata fsdata; + fat_itr itrblock, *itr = &itrblock; int ret; - loff_t size; - ret = do_fat_read_at(filename, 0, NULL, 0, LS_NO, 1, &size); + ret = fat_itr_root(itr, &fsdata); + if (ret) + return 0; + + ret = fat_itr_resolve(itr, filename, TYPE_ANY); return ret == 0; } int fat_size(const char *filename, loff_t *size) { - return do_fat_read_at(filename, 0, NULL, 0, LS_NO, 1, size); + fsdata fsdata; + fat_itr itrblock, *itr = &itrblock; + int ret; + + ret = fat_itr_root(itr, &fsdata); + if (ret) + return ret; + + ret = fat_itr_resolve(itr, filename, TYPE_FILE); + if (ret) { + /* + * Directories don't have size, but fs_size() is not + * expected to fail if passed a directory path: + */ + fat_itr_root(itr, &fsdata); + if (!fat_itr_resolve(itr, filename, TYPE_DIR)) { + *size = 0; + return 0; + } + return ret; + } + + *size = FAT2CPU32(itr->dent->size); + + return 0; } int file_fat_read_at(const char *filename, loff_t pos, void *buffer, loff_t maxsize, loff_t *actread) { + fsdata fsdata; + fat_itr itrblock, *itr = &itrblock; + int ret; + + ret = fat_itr_root(itr, &fsdata); + if (ret) + return ret; + + ret = fat_itr_resolve(itr, filename, TYPE_FILE); + if (ret) + return ret; + printf("reading %s\n", filename); - return do_fat_read_at(filename, pos, buffer, maxsize, LS_NO, 0, - actread); + return get_contents(&fsdata, itr->dent, pos, buffer, maxsize, actread); } int file_fat_read(const char *filename, void *buffer, int maxsize) diff --git a/include/fat.h b/include/fat.h index 21bb6666cf..18d8981c48 100644 --- a/include/fat.h +++ b/include/fat.h @@ -58,12 +58,6 @@ */ #define LAST_LONG_ENTRY_MASK 0x40 -/* Flags telling whether we should read a file or list a directory */ -#define LS_NO 0 -#define LS_YES 1 -#define LS_DIR 1 -#define LS_ROOT 2 - #define ISDIRDELIM(c) ((c) == '/' || (c) == '\\') #define FSTYPE_NONE (-1)