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Commit deb8274a authored by Steven J. Magnani's avatar Steven J. Magnani Committed by Linus Torvalds
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fat: refactor shortname parsing 



Nearly identical shortname parsing is performed in fat_search_long() and
__fat_readdir().  Extract this code into a function that may be called by
both.

Signed-off-by: default avatarSteven J. Magnani <steve@digidescorp.com>
Acked-by: default avatarOGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
parent a943ed71

fs/fat/dir.c

+137 −118
Original line number Diff line number Diff line
@@ -35,6 +35,11 @@ 
#define FAT_MAX_UNI_CHARS	((MSDOS_SLOTS - 1) * 13 + 1)

#define FAT_MAX_UNI_SIZE	(FAT_MAX_UNI_CHARS * sizeof(wchar_t))



static inline unsigned char fat_tolower(unsigned char c)

{

	return ((c >= 'A') && (c <= 'Z')) ? c+32 : c;

}



static inline loff_t fat_make_i_pos(struct super_block *sb,

				    struct buffer_head *bh,

				    struct msdos_dir_entry *de)
@@ -333,6 +338,124 @@ static int fat_parse_long(struct inode *dir, loff_t *pos, 
	return 0;

}



/**

 * fat_parse_short - Parse MS-DOS (short) directory entry.

 * @sb:		superblock

 * @de:		directory entry to parse

 * @name:	FAT_MAX_SHORT_SIZE array in which to place extracted name

 * @dot_hidden:	Nonzero == prepend '.' to names with ATTR_HIDDEN

 *

 * Returns the number of characters extracted into 'name'.

 */

static int fat_parse_short(struct super_block *sb,

			   const struct msdos_dir_entry *de,

			   unsigned char *name, int dot_hidden)

{

	const struct msdos_sb_info *sbi = MSDOS_SB(sb);

	int isvfat = sbi->options.isvfat;

	int nocase = sbi->options.nocase;

	unsigned short opt_shortname = sbi->options.shortname;

	struct nls_table *nls_disk = sbi->nls_disk;

	wchar_t uni_name[14];

	unsigned char c, work[MSDOS_NAME];

	unsigned char *ptname = name;

	int chi, chl, i, j, k;

	int dotoffset = 0;

	int name_len = 0, uni_len = 0;



	if (!isvfat && dot_hidden && (de->attr & ATTR_HIDDEN)) {

		*ptname++ = '.';

		dotoffset = 1;

	}



	memcpy(work, de->name, sizeof(work));

	/* see namei.c, msdos_format_name */

	if (work[0] == 0x05)

		work[0] = 0xE5;



	/* Filename */

	for (i = 0, j = 0; i < 8;) {

		c = work[i];

		if (!c)

			break;

		chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,

					&uni_name[j++], opt_shortname,

					de->lcase & CASE_LOWER_BASE);

		if (chl <= 1) {

			if (!isvfat)

				ptname[i] = nocase ? c : fat_tolower(c);

			i++;

			if (c != ' ') {

				name_len = i;

				uni_len  = j;

			}

		} else {

			uni_len = j;

			if (isvfat)

				i += min(chl, 8-i);

			else {

				for (chi = 0; chi < chl && i < 8; chi++, i++)

					ptname[i] = work[i];

			}

			if (chl)

				name_len = i;

		}

	}



	i = name_len;

	j = uni_len;

	fat_short2uni(nls_disk, ".", 1, &uni_name[j++]);

	if (!isvfat)

		ptname[i] = '.';

	i++;



	/* Extension */

	for (k = 8; k < MSDOS_NAME;) {

		c = work[k];

		if (!c)

			break;

		chl = fat_shortname2uni(nls_disk, &work[k], MSDOS_NAME - k,

					&uni_name[j++], opt_shortname,

					de->lcase & CASE_LOWER_EXT);

		if (chl <= 1) {

			k++;

			if (!isvfat)

				ptname[i] = nocase ? c : fat_tolower(c);

			i++;

			if (c != ' ') {

				name_len = i;

				uni_len  = j;

			}

		} else {

			uni_len = j;

			if (isvfat) {

				int offset = min(chl, MSDOS_NAME-k);

				k += offset;

				i += offset;

			} else {

				for (chi = 0; chi < chl && k < MSDOS_NAME;

				     chi++, i++, k++) {

						ptname[i] = work[k];

				}

			}

			if (chl)

				name_len = i;

		}

	}



	if (name_len > 0) {

		name_len += dotoffset;



		if (sbi->options.isvfat) {

			uni_name[uni_len] = 0x0000;

			name_len = fat_uni_to_x8(sb, uni_name, name,

						 FAT_MAX_SHORT_SIZE);

		}

	}



	return name_len;

}



/*

 * Return values: negative -> error, 0 -> not found, positive -> found,

 * value is the total amount of slots, including the shortname entry.
@@ -344,15 +467,11 @@ int fat_search_long(struct inode *inode, const unsigned char *name, 
	struct msdos_sb_info *sbi = MSDOS_SB(sb);

	struct buffer_head *bh = NULL;

	struct msdos_dir_entry *de;

	struct nls_table *nls_disk = sbi->nls_disk;

	unsigned char nr_slots;

	wchar_t bufuname[14];

	wchar_t *unicode = NULL;

	unsigned char work[MSDOS_NAME];

	unsigned char bufname[FAT_MAX_SHORT_SIZE];

	unsigned short opt_shortname = sbi->options.shortname;

	loff_t cpos = 0;

	int chl, i, j, last_u, err, len;

	int err, len;



	err = -ENOENT;

	while (1) {
@@ -380,47 +499,16 @@ int fat_search_long(struct inode *inode, const unsigned char *name, 
				goto end_of_dir;

		}



		memcpy(work, de->name, sizeof(de->name));

		/* see namei.c, msdos_format_name */

		if (work[0] == 0x05)

			work[0] = 0xE5;

		for (i = 0, j = 0, last_u = 0; i < 8;) {

			if (!work[i])

				break;

			chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,

						&bufuname[j++], opt_shortname,

						de->lcase & CASE_LOWER_BASE);

			if (chl <= 1) {

				if (work[i] != ' ')

					last_u = j;

			} else {

				last_u = j;

			}

			i += chl;

		}

		j = last_u;

		fat_short2uni(nls_disk, ".", 1, &bufuname[j++]);

		for (i = 8; i < MSDOS_NAME;) {

			if (!work[i])

				break;

			chl = fat_shortname2uni(nls_disk, &work[i],

						MSDOS_NAME - i,

						&bufuname[j++], opt_shortname,

						de->lcase & CASE_LOWER_EXT);

			if (chl <= 1) {

				if (work[i] != ' ')

					last_u = j;

			} else {

				last_u = j;

			}

			i += chl;

		}

		if (!last_u)

		/* Never prepend '.' to hidden files here.

		 * That is done only for msdos mounts (and only when

		 * 'dotsOK=yes'); if we are executing here, it is in the

		 * context of a vfat mount.

		 */

		len = fat_parse_short(sb, de, bufname, 0);

		if (len == 0)

			continue;



		/* Compare shortname */

		bufuname[last_u] = 0x0000;

		len = fat_uni_to_x8(sb, bufuname, bufname, sizeof(bufname));

		if (fat_name_match(sbi, name, name_len, bufname, len))

			goto found;
@@ -469,20 +557,15 @@ static int __fat_readdir(struct inode *inode, struct file *filp, void *dirent, 
	struct msdos_sb_info *sbi = MSDOS_SB(sb);

	struct buffer_head *bh;

	struct msdos_dir_entry *de;

	struct nls_table *nls_disk = sbi->nls_disk;

	unsigned char nr_slots;

	wchar_t bufuname[14];

	wchar_t *unicode = NULL;

	unsigned char c, work[MSDOS_NAME];

	unsigned char bufname[FAT_MAX_SHORT_SIZE], *ptname = bufname;

	unsigned short opt_shortname = sbi->options.shortname;

	unsigned char bufname[FAT_MAX_SHORT_SIZE];

	int isvfat = sbi->options.isvfat;

	int nocase = sbi->options.nocase;

	const char *fill_name = NULL;

	unsigned long inum;

	unsigned long lpos, dummy, *furrfu = &lpos;

	loff_t cpos;

	int chi, chl, i, i2, j, last, last_u, dotoffset = 0, fill_len = 0;

	int short_len = 0, fill_len = 0;

	int ret = 0;



	lock_super(sb);
@@ -556,74 +639,10 @@ static int __fat_readdir(struct inode *inode, struct file *filp, void *dirent, 
		}

	}



	if (sbi->options.dotsOK) {

		ptname = bufname;

		dotoffset = 0;

		if (de->attr & ATTR_HIDDEN) {

			*ptname++ = '.';

			dotoffset = 1;

		}

	}



	memcpy(work, de->name, sizeof(de->name));

	/* see namei.c, msdos_format_name */

	if (work[0] == 0x05)

		work[0] = 0xE5;

	for (i = 0, j = 0, last = 0, last_u = 0; i < 8;) {

		if (!(c = work[i]))

			break;

		chl = fat_shortname2uni(nls_disk, &work[i], 8 - i,

					&bufuname[j++], opt_shortname,

					de->lcase & CASE_LOWER_BASE);

		if (chl <= 1) {

			ptname[i++] = (!nocase && c>='A' && c<='Z') ? c+32 : c;

			if (c != ' ') {

				last = i;

				last_u = j;

			}

		} else {

			last_u = j;

			for (chi = 0; chi < chl && i < 8; chi++) {

				ptname[i] = work[i];

				i++; last = i;

			}

		}

	}

	i = last;

	j = last_u;

	fat_short2uni(nls_disk, ".", 1, &bufuname[j++]);

	ptname[i++] = '.';

	for (i2 = 8; i2 < MSDOS_NAME;) {

		if (!(c = work[i2]))

			break;

		chl = fat_shortname2uni(nls_disk, &work[i2], MSDOS_NAME - i2,

					&bufuname[j++], opt_shortname,

					de->lcase & CASE_LOWER_EXT);

		if (chl <= 1) {

			i2++;

			ptname[i++] = (!nocase && c>='A' && c<='Z') ? c+32 : c;

			if (c != ' ') {

				last = i;

				last_u = j;

			}

		} else {

			last_u = j;

			for (chi = 0; chi < chl && i2 < MSDOS_NAME; chi++) {

				ptname[i++] = work[i2++];

				last = i;

			}

		}

	}

	if (!last)

	short_len = fat_parse_short(sb, de, bufname, sbi->options.dotsOK);

	if (short_len == 0)

		goto record_end;



	i = last + dotoffset;

	j = last_u;



	if (isvfat) {

		bufuname[j] = 0x0000;

		i = fat_uni_to_x8(sb, bufuname, bufname, sizeof(bufname));

	}

	if (nr_slots) {

		/* hack for fat_ioctl_filldir() */

		struct fat_ioctl_filldir_callback *p = dirent;
@@ -631,12 +650,12 @@ static int __fat_readdir(struct inode *inode, struct file *filp, void *dirent, 
		p->longname = fill_name;

		p->long_len = fill_len;

		p->shortname = bufname;

		p->short_len = i;

		p->short_len = short_len;

		fill_name = NULL;

		fill_len = 0;

	} else {

		fill_name = bufname;

		fill_len = i;

		fill_len = short_len;

	}



start_filldir: