1 files changed, 185 insertions, 45 deletions

diff --git a/fs/hfsplus/unicode.c b/fs/hfsplus/unicode.c
index 689c8bd721fb..9e10f9444b64 100644
--- a/fs/hfsplus/unicode.c
+++ b/fs/hfsplus/unicode.c
@@ -239,61 +239,201 @@ out:
         return res;
 }
 
-int hfsplus_asc2uni(struct super_block *sb, struct hfsplus_unistr *ustr, const char *astr, int len)
+/*
+ * Convert one or more ASCII characters into a single unicode character.
+ * Returns the number of ASCII characters corresponding to the unicode char.
+ */
+static inline int asc2unichar(struct super_block *sb, const char *astr, int len,
+                              wchar_t *uc)
 {
-        struct nls_table *nls = HFSPLUS_SB(sb).nls;
-        int size, off, decompose;
+        int size = HFSPLUS_SB(sb).nls->char2uni(astr, len, uc);
+        if (size <= 0) {
+                *uc = '?';
+                size = 1;
+        }
+        switch (*uc) {
+        case 0x2400:
+                *uc = 0;
+                break;
+        case ':':
+                *uc = '/';
+                break;
+        }
+        return size;
+}
+
+/* Decomposes a single unicode character. */
+static inline u16 *decompose_unichar(wchar_t uc, int *size)
+{
+        int off;
+
+        off = hfsplus_decompose_table[(uc >> 12) & 0xf];
+        if (off == 0 || off == 0xffff)
+                return NULL;
+
+        off = hfsplus_decompose_table[off + ((uc >> 8) & 0xf)];
+        if (!off)
+                return NULL;
+
+        off = hfsplus_decompose_table[off + ((uc >> 4) & 0xf)];
+        if (!off)
+                return NULL;
+
+        off = hfsplus_decompose_table[off + (uc & 0xf)];
+        *size = off & 3;
+        if (*size == 0)
+                return NULL;
+        return hfsplus_decompose_table + (off / 4);
+}
+
+int hfsplus_asc2uni(struct super_block *sb, struct hfsplus_unistr *ustr,
+                    const char *astr, int len)
+{
+        int size, dsize, decompose;
+        u16 *dstr, outlen = 0;
         wchar_t c;
-        u16 outlen = 0;
 
         decompose = !(HFSPLUS_SB(sb).flags & HFSPLUS_SB_NODECOMPOSE);
-
         while (outlen < HFSPLUS_MAX_STRLEN && len > 0) {
-                size = nls->char2uni(astr, len, &c);
-                if (size <= 0) {
-                        c = '?';
-                        size = 1;
-                }
-                astr += size;
-                len -= size;
-                switch (c) {
-                case 0x2400:
-                        c = 0;
-                        break;
-                case ':':
-                        c = '/';
-                        break;
-                }
-                if (c >= 0xc0 && decompose) {
-                        off = hfsplus_decompose_table[(c >> 12) & 0xf];
-                        if (!off)
-                                goto done;
-                        if (off == 0xffff) {
-                                goto done;
-                        }
-                        off = hfsplus_decompose_table[off + ((c >> 8) & 0xf)];
-                        if (!off)
-                                goto done;
-                        off = hfsplus_decompose_table[off + ((c >> 4) & 0xf)];
-                        if (!off)
-                                goto done;
-                        off = hfsplus_decompose_table[off + (c & 0xf)];
-                        size = off & 3;
-                        if (!size)
-                                goto done;
-                        off /= 4;
-                        if (outlen + size > HFSPLUS_MAX_STRLEN)
+                size = asc2unichar(sb, astr, len, &c);
+
+                if (decompose && (dstr = decompose_unichar(c, &dsize))) {
+                        if (outlen + dsize > HFSPLUS_MAX_STRLEN)
                                 break;
                         do {
-                                ustr->unicode[outlen++] = cpu_to_be16(hfsplus_decompose_table[off++]);
-                        } while (--size > 0);
-                        continue;
-                }
-        done:
-                ustr->unicode[outlen++] = cpu_to_be16(c);
+                                ustr->unicode[outlen++] = cpu_to_be16(*dstr++);
+                        } while (--dsize > 0);
+                } else
+                        ustr->unicode[outlen++] = cpu_to_be16(c);
+
+                astr += size;
+                len -= size;
         }
         ustr->length = cpu_to_be16(outlen);
         if (len > 0)
                 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;
+}