Fixed MTP to work with TWRP

fs/hfsplus/unicode.c

@@ -0,0 +1,469 @@
+/*
+ *  linux/fs/hfsplus/unicode.c
+ *
+ * Copyright (C) 2001
+ * Brad Boyer (flar@allandria.com)
+ * (C) 2003 Ardis Technologies <roman@ardistech.com>
+ *
+ * Handler routines for unicode strings
+ */
+
+#include <linux/types.h>
+#include <linux/nls.h>
+#include "hfsplus_fs.h"
+#include "hfsplus_raw.h"
+
+/* Fold the case of a unicode char, given the 16 bit value */
+/* Returns folded char, or 0 if ignorable */
+static inline u16 case_fold(u16 c)
+{
+	u16 tmp;
+
+	tmp = hfsplus_case_fold_table[c >> 8];
+	if (tmp)
+		tmp = hfsplus_case_fold_table[tmp + (c & 0xff)];
+	else
+		tmp = c;
+	return tmp;
+}
+
+/* Compare unicode strings, return values like normal strcmp */
+int hfsplus_strcasecmp(const struct hfsplus_unistr *s1,
+		       const struct hfsplus_unistr *s2)
+{
+	u16 len1, len2, c1, c2;
+	const hfsplus_unichr *p1, *p2;
+
+	len1 = be16_to_cpu(s1->length);
+	len2 = be16_to_cpu(s2->length);
+	p1 = s1->unicode;
+	p2 = s2->unicode;
+
+	while (1) {
+		c1 = c2 = 0;
+
+		while (len1 && !c1) {
+			c1 = case_fold(be16_to_cpu(*p1));
+			p1++;
+			len1--;
+		}
+		while (len2 && !c2) {
+			c2 = case_fold(be16_to_cpu(*p2));
+			p2++;
+			len2--;
+		}
+
+		if (c1 != c2)
+			return (c1 < c2) ? -1 : 1;
+		if (!c1 && !c2)
+			return 0;
+	}
+}
+
+/* Compare names as a sequence of 16-bit unsigned integers */
+int hfsplus_strcmp(const struct hfsplus_unistr *s1,
+		   const struct hfsplus_unistr *s2)
+{
+	u16 len1, len2, c1, c2;
+	const hfsplus_unichr *p1, *p2;
+	int len;
+
+	len1 = be16_to_cpu(s1->length);
+	len2 = be16_to_cpu(s2->length);
+	p1 = s1->unicode;
+	p2 = s2->unicode;
+
+	for (len = min(len1, len2); len > 0; len--) {
+		c1 = be16_to_cpu(*p1);
+		c2 = be16_to_cpu(*p2);
+		if (c1 != c2)
+			return c1 < c2 ? -1 : 1;
+		p1++;
+		p2++;
+	}
+
+	return len1 < len2 ? -1 :
+	       len1 > len2 ? 1 : 0;
+}
+
+
+#define Hangul_SBase	0xac00
+#define Hangul_LBase	0x1100
+#define Hangul_VBase	0x1161
+#define Hangul_TBase	0x11a7
+#define Hangul_SCount	11172
+#define Hangul_LCount	19
+#define Hangul_VCount	21
+#define Hangul_TCount	28
+#define Hangul_NCount	(Hangul_VCount * Hangul_TCount)
+
+
+static u16 *hfsplus_compose_lookup(u16 *p, u16 cc)
+{
+	int i, s, e;
+
+	s = 1;
+	e = p[1];
+	if (!e || cc < p[s * 2] || cc > p[e * 2])
+		return NULL;
+	do {
+		i = (s + e) / 2;
+		if (cc > p[i * 2])
+			s = i + 1;
+		else if (cc < p[i * 2])
+			e = i - 1;
+		else
+			return hfsplus_compose_table + p[i * 2 + 1];
+	} while (s <= e);
+	return NULL;
+}
+
+int hfsplus_uni2asc(struct super_block *sb,
+		const struct hfsplus_unistr *ustr,
+		char *astr, int *len_p)
+{
+	const hfsplus_unichr *ip;
+	struct nls_table *nls = HFSPLUS_SB(sb)->nls;
+	u8 *op;
+	u16 cc, c0, c1;
+	u16 *ce1, *ce2;
+	int i, len, ustrlen, res, compose;
+
+	op = astr;
+	ip = ustr->unicode;
+	ustrlen = be16_to_cpu(ustr->length);
+	len = *len_p;
+	ce1 = NULL;
+	compose = !test_bit(HFSPLUS_SB_NODECOMPOSE, &HFSPLUS_SB(sb)->flags);
+
+	while (ustrlen > 0) {
+		c0 = be16_to_cpu(*ip++);
+		ustrlen--;
+		/* search for single decomposed char */
+		if (likely(compose))
+			ce1 = hfsplus_compose_lookup(hfsplus_compose_table, c0);
+		if (ce1)
+			cc = ce1[0];
+		else
+			cc = 0;
+		if (cc) {
+			/* start of a possibly decomposed Hangul char */
+			if (cc != 0xffff)
+				goto done;
+			if (!ustrlen)
+				goto same;
+			c1 = be16_to_cpu(*ip) - Hangul_VBase;
+			if (c1 < Hangul_VCount) {
+				/* compose the Hangul char */
+				cc = (c0 - Hangul_LBase) * Hangul_VCount;
+				cc = (cc + c1) * Hangul_TCount;
+				cc += Hangul_SBase;
+				ip++;
+				ustrlen--;
+				if (!ustrlen)
+					goto done;
+				c1 = be16_to_cpu(*ip) - Hangul_TBase;
+				if (c1 > 0 && c1 < Hangul_TCount) {
+					cc += c1;
+					ip++;
+					ustrlen--;
+				}
+				goto done;
+			}
+		}
+		while (1) {
+			/* main loop for common case of not composed chars */
+			if (!ustrlen)
+				goto same;
+			c1 = be16_to_cpu(*ip);
+			if (likely(compose))
+				ce1 = hfsplus_compose_lookup(
+					hfsplus_compose_table, c1);
+			if (ce1)
+				break;
+			switch (c0) {
+			case 0:
+				c0 = 0x2400;
+				break;
+			case '/':
+				c0 = ':';
+				break;
+			}
+			res = nls->uni2char(c0, op, len);
+			if (res < 0) {
+				if (res == -ENAMETOOLONG)
+					goto out;
+				*op = '?';
+				res = 1;
+			}
+			op += res;
+			len -= res;
+			c0 = c1;
+			ip++;
+			ustrlen--;
+		}
+		ce2 = hfsplus_compose_lookup(ce1, c0);
+		if (ce2) {
+			i = 1;
+			while (i < ustrlen) {
+				ce1 = hfsplus_compose_lookup(ce2,
+					be16_to_cpu(ip[i]));
+				if (!ce1)
+					break;
+				i++;
+				ce2 = ce1;
+			}
+			cc = ce2[0];
+			if (cc) {
+				ip += i;
+				ustrlen -= i;
+				goto done;
+			}
+		}
+same:
+		switch (c0) {
+		case 0:
+			cc = 0x2400;
+			break;
+		case '/':
+			cc = ':';
+			break;
+		default:
+			cc = c0;
+		}
+done:
+		res = nls->uni2char(cc, op, len);
+		if (res < 0) {
+			if (res == -ENAMETOOLONG)
+				goto out;
+			*op = '?';
+			res = 1;
+		}
+		op += res;
+		len -= res;
+	}
+	res = 0;
+out:
+	*len_p = (char *)op - astr;
+	return res;
+}
+
+/*
+ * 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)
+{
+	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, int max_unistr_len,
+		    const char *astr, int len)
+{
+	int size, dsize, decompose;
+	u16 *dstr, outlen = 0;
+	wchar_t c;
+
+	decompose = !test_bit(HFSPLUS_SB_NODECOMPOSE, &HFSPLUS_SB(sb)->flags);
+	while (outlen < max_unistr_len && len > 0) {
+		size = asc2unichar(sb, astr, len, &c);
+
+		if (decompose)
+			dstr = decompose_unichar(c, &dsize);
+		else
+			dstr = NULL;
+		if (dstr) {
+			if (outlen + dsize > max_unistr_len)
+				break;
+			do {
+				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(const struct dentry *dentry, struct qstr *str)
+{
+	struct super_block *sb = dentry->d_sb;
+	const char *astr;
+	const u16 *dstr;
+	int casefold, decompose, size, len;
+	unsigned long hash;
+	wchar_t c;
+	u16 c2;
+
+	casefold = test_bit(HFSPLUS_SB_CASEFOLD, &HFSPLUS_SB(sb)->flags);
+	decompose = !test_bit(HFSPLUS_SB_NODECOMPOSE, &HFSPLUS_SB(sb)->flags);
+	hash = init_name_hash();
+	astr = str->name;
+	len = str->len;
+	while (len > 0) {
+		int uninitialized_var(dsize);
+		size = asc2unichar(sb, astr, len, &c);
+		astr += size;
+		len -= size;
+
+		if (decompose)
+			dstr = decompose_unichar(c, &dsize);
+		else
+			dstr = NULL;
+		if (dstr) {
+			do {
+				c2 = *dstr++;
+				if (casefold)
+					c2 = case_fold(c2);
+				if (!casefold || c2)
+					hash = partial_name_hash(c2, hash);
+			} while (--dsize > 0);
+		} else {
+			c2 = c;
+			if (casefold)
+				c2 = case_fold(c2);
+			if (!casefold || 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(const struct dentry *parent, const struct dentry *dentry,
+		unsigned int len, const char *str, const struct qstr *name)
+{
+	struct super_block *sb = parent->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 = test_bit(HFSPLUS_SB_CASEFOLD, &HFSPLUS_SB(sb)->flags);
+	decompose = !test_bit(HFSPLUS_SB_NODECOMPOSE, &HFSPLUS_SB(sb)->flags);
+	astr1 = str;
+	len1 = len;
+	astr2 = name->name;
+	len2 = name->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);
+			if (!decompose || !dstr1) {
+				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);
+			if (!decompose || !dstr2) {
+				c2 = c;
+				dstr2 = &c2;
+				dsize2 = 1;
+			}
+		}
+
+		c1 = *dstr1;
+		c2 = *dstr2;
+		if (casefold) {
+			c1 = case_fold(c1);
+			if (!c1) {
+				dstr1++;
+				dsize1--;
+				continue;
+			}
+			c2 = case_fold(c2);
+			if (!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;
+}