From deb8274a0cf44827ec260330cc1d94d0f3dcfb94 Mon Sep 17 00:00:00 2001 From: "Steven J. Magnani" Date: Mon, 30 Jul 2012 14:42:16 -0700 Subject: 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: Steven J. Magnani Acked-by: OGAWA Hirofumi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- fs/fat/dir.c | 255 ++++++++++++++++++++++++++++++++--------------------------- 1 file changed, 137 insertions(+), 118 deletions(-) diff --git a/fs/fat/dir.c b/fs/fat/dir.c index 6eaa28c98ad1..dc49ed2cbffa 100644 --- a/fs/fat/dir.c +++ b/fs/fat/dir.c @@ -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 @@ parse_long: 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 @@ parse_record: 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 @@ parse_record: } } - 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 @@ parse_record: 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: -- cgit v1.2.3