On Mon, Aug 14, 2017 at 9:47 AM, Brüns, Stefan Stefan.Bruens@rwth-aachen.de wrote:
On Montag, 14. August 2017 15:16:15 CEST Rob Clark wrote:
And drop a whole lot of ugly code!
Signed-off-by: Rob Clark robdclark@gmail.com
fs/fat/fat.c | 723 ++++++---------------------------------------------------- include/fat.h | 6 - 2 files changed, 75 insertions(+), 654 deletions(-)
Nice, even after accounting for the ~300 lines added for the iterators :-)
Two comments inline ...
diff --git a/fs/fat/fat.c b/fs/fat/fat.c index 69fa7f4cab..a50a10ba47 100644 --- a/fs/fat/fat.c +++ b/fs/fat/fat.c @@ -119,22 +119,6 @@ int fat_register_device(struct blk_desc *dev_desc, int part_no) }
[...]
-/*
- Extract zero terminated short name from a directory entry.
*/ static void get_name(dir_entry *dirent, char *s_name) @@ -468,95 +452,6 @@ static int slot2str(dir_slot *slotptr, char *l_name, int *idx) return 0; }
[...]
-}
/* Calculate short name checksum */ static __u8 mkcksum(const char name[8], const char ext[3]) { @@ -572,170 +467,11 @@ static __u8 mkcksum(const char name[8], const char ext[3]) return ret;
[...]
/*
- Read boot sector and volume info from a FAT filesystem
@@ -877,374 +613,6 @@ static int get_fs_info(fsdata *mydata) return 0; }
[...]
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.*/Have you checked this case still works? AFAICS this is not covered in fs- test.sh. Examples of suitables sandbox commands are given in the commit message of:
Directories split across clusters is definitely something that I've tested. Not sure if some of them had vfat names spanning a cluster, but handling that is inherent in the design, as it never needs more than a single dent at a time to parse vfat names.
18a10d46f267057ede0490ddba71c106475b4eb1 (fat: handle paths that include ../)
hmm, but it does look like I'm missing something to ../ back to root dir..
BR, -R
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
@@ -1571,12 +939,6 @@ 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; @@ -1641,31 +1003,96 @@ 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++;}}printf("\n%d file(s), %d dir(s)\n\n", files, dirs);
return do_fat_read(dir, NULL, 0, LS_YES, &size);
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 ret;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;}It might be simpler to resolve with (TYPE_ANY) and check the TYPE of the returned iterator.
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 6d3fc8e4a6..3e7ab9ea8d 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)