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author | Duane Griffin <duaneg@dghda.com> | 2007-07-15 23:41:23 -0700 |
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committer | Linus Torvalds <torvalds@woody.linux-foundation.org> | 2007-07-16 09:05:49 -0700 |
commit | d45bce8faf55511ec7d7ffc301461d864d67f1af (patch) | |
tree | 1b3c33667f5cb30d3daa91ddd50a726045991d74 /fs/hfsplus/unicode.c | |
parent | 1e96b7ca1e8f17c5117da369daaa7cf2edfdf9b1 (diff) | |
download | linux-stable-d45bce8faf55511ec7d7ffc301461d864d67f1af.tar.gz linux-stable-d45bce8faf55511ec7d7ffc301461d864d67f1af.tar.bz2 linux-stable-d45bce8faf55511ec7d7ffc301461d864d67f1af.zip |
HFS+: add custom dentry hash and comparison operations
Add custom dentry hash and comparison operations for HFS+ filesystems that are
case-insensitive and/or do automatic unicode decomposition. The new
operations reuse the existing HFS+ ASCII to unicode conversion, unicode
decomposition and case folding functionality.
Signed-off-by: Duane Griffin <duaneg@dghda.com>
Signed-off-by: Roman Zippel <zippel@linux-m68k.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/hfsplus/unicode.c')
-rw-r--r-- | fs/hfsplus/unicode.c | 123 |
1 files changed, 123 insertions, 0 deletions
diff --git a/fs/hfsplus/unicode.c b/fs/hfsplus/unicode.c index 5df0052b2775..9e10f9444b64 100644 --- a/fs/hfsplus/unicode.c +++ b/fs/hfsplus/unicode.c @@ -314,3 +314,126 @@ int hfsplus_asc2uni(struct super_block *sb, struct hfsplus_unistr *ustr, return -ENAMETOOLONG; return 0; } + +/* + * Hash a string to an integer as appropriate for the HFS+ filesystem. + * Composed unicode characters are decomposed and case-folding is performed + * if the appropriate bits are (un)set on the superblock. + */ +int hfsplus_hash_dentry(struct dentry *dentry, struct qstr *str) +{ + struct super_block *sb = dentry->d_sb; + const char *astr; + const u16 *dstr; + int casefold, decompose, size, dsize, len; + unsigned long hash; + wchar_t c; + u16 c2; + + casefold = (HFSPLUS_SB(sb).flags & HFSPLUS_SB_CASEFOLD); + decompose = !(HFSPLUS_SB(sb).flags & HFSPLUS_SB_NODECOMPOSE); + hash = init_name_hash(); + astr = str->name; + len = str->len; + while (len > 0) { + size = asc2unichar(sb, astr, len, &c); + astr += size; + len -= size; + + if (decompose && (dstr = decompose_unichar(c, &dsize))) { + do { + c2 = *dstr++; + if (!casefold || (c2 = case_fold(c2))) + hash = partial_name_hash(c2, hash); + } while (--dsize > 0); + } else { + c2 = c; + if (!casefold || (c2 = case_fold(c2))) + hash = partial_name_hash(c2, hash); + } + } + str->hash = end_name_hash(hash); + + return 0; +} + +/* + * Compare strings with HFS+ filename ordering. + * Composed unicode characters are decomposed and case-folding is performed + * if the appropriate bits are (un)set on the superblock. + */ +int hfsplus_compare_dentry(struct dentry *dentry, struct qstr *s1, struct qstr *s2) +{ + struct super_block *sb = dentry->d_sb; + int casefold, decompose, size; + int dsize1, dsize2, len1, len2; + const u16 *dstr1, *dstr2; + const char *astr1, *astr2; + u16 c1, c2; + wchar_t c; + + casefold = (HFSPLUS_SB(sb).flags & HFSPLUS_SB_CASEFOLD); + decompose = !(HFSPLUS_SB(sb).flags & HFSPLUS_SB_NODECOMPOSE); + astr1 = s1->name; + len1 = s1->len; + astr2 = s2->name; + len2 = s2->len; + dsize1 = dsize2 = 0; + dstr1 = dstr2 = NULL; + + while (len1 > 0 && len2 > 0) { + if (!dsize1) { + size = asc2unichar(sb, astr1, len1, &c); + astr1 += size; + len1 -= size; + + if (!decompose || !(dstr1 = decompose_unichar(c, &dsize1))) { + c1 = c; + dstr1 = &c1; + dsize1 = 1; + } + } + + if (!dsize2) { + size = asc2unichar(sb, astr2, len2, &c); + astr2 += size; + len2 -= size; + + if (!decompose || !(dstr2 = decompose_unichar(c, &dsize2))) { + c2 = c; + dstr2 = &c2; + dsize2 = 1; + } + } + + c1 = *dstr1; + c2 = *dstr2; + if (casefold) { + if (!(c1 = case_fold(c1))) { + dstr1++; + dsize1--; + continue; + } + if (!(c2 = case_fold(c2))) { + dstr2++; + dsize2--; + continue; + } + } + if (c1 < c2) + return -1; + else if (c1 > c2) + return 1; + + dstr1++; + dsize1--; + dstr2++; + dsize2--; + } + + if (len1 < len2) + return -1; + if (len1 > len2) + return 1; + return 0; +} |