FROMLIST: unicode: Add utf8_casefold_hash

This adds a case insensitive hash function to allow taking the hash
without needing to allocate a casefolded copy of the string.

Signed-off-by: Daniel Rosenberg <drosen@google.com>
Test: Boots, /data/media is case insensitive
Bug: 138322712
Link: https://lore.kernel.org/linux-f2fs-devel/20200208013552.241832-1-drosen@google.com/T/#t
Change-Id: I43c7d38a8e22f4479397f35e6343bd326901cdba
This commit is contained in:
Daniel Rosenberg 2020-02-05 16:40:52 -08:00
parent aaf60404d6
commit 27888d0d02
2 changed files with 25 additions and 1 deletions

View file

@ -6,6 +6,7 @@
#include <linux/parser.h> #include <linux/parser.h>
#include <linux/errno.h> #include <linux/errno.h>
#include <linux/unicode.h> #include <linux/unicode.h>
#include <linux/stringhash.h>
#include "utf8n.h" #include "utf8n.h"
@ -122,9 +123,29 @@ int utf8_casefold(const struct unicode_map *um, const struct qstr *str,
} }
return -EINVAL; return -EINVAL;
} }
EXPORT_SYMBOL(utf8_casefold); EXPORT_SYMBOL(utf8_casefold);
int utf8_casefold_hash(const struct unicode_map *um, const void *salt,
struct qstr *str)
{
const struct utf8data *data = utf8nfdicf(um->version);
struct utf8cursor cur;
int c;
unsigned long hash = init_name_hash(salt);
if (utf8ncursor(&cur, data, str->name, str->len) < 0)
return -EINVAL;
while ((c = utf8byte(&cur))) {
if (c < 0)
return c;
hash = partial_name_hash((unsigned char)c, hash);
}
str->hash = end_name_hash(hash);
return 0;
}
EXPORT_SYMBOL(utf8_casefold_hash);
int utf8_normalize(const struct unicode_map *um, const struct qstr *str, int utf8_normalize(const struct unicode_map *um, const struct qstr *str,
unsigned char *dest, size_t dlen) unsigned char *dest, size_t dlen)
{ {

View file

@ -27,6 +27,9 @@ int utf8_normalize(const struct unicode_map *um, const struct qstr *str,
int utf8_casefold(const struct unicode_map *um, const struct qstr *str, int utf8_casefold(const struct unicode_map *um, const struct qstr *str,
unsigned char *dest, size_t dlen); unsigned char *dest, size_t dlen);
int utf8_casefold_hash(const struct unicode_map *um, const void *salt,
struct qstr *str);
struct unicode_map *utf8_load(const char *version); struct unicode_map *utf8_load(const char *version);
void utf8_unload(struct unicode_map *um); void utf8_unload(struct unicode_map *um);