[PATCH v8 1/8] unicode: Add utf8_casefold_hash
From: Daniel Rosenberg <hidden>
Date: 2020-03-07 02:36:39
Also in:
linux-ext4, linux-f2fs-devel, linux-fscrypt, linux-fsdevel, lkml
Subsystem:
filesystems (vfs and infrastructure), the rest, unicode subsystem · Maintainers:
Alexander Viro, Christian Brauner, Linus Torvalds, Gabriel Krisman Bertazi
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 <redacted> --- fs/unicode/utf8-core.c | 23 ++++++++++++++++++++++- include/linux/unicode.h | 3 +++ 2 files changed, 25 insertions(+), 1 deletion(-)
diff --git a/fs/unicode/utf8-core.c b/fs/unicode/utf8-core.c
index 2a878b739115d..90656b9980720 100644
--- a/fs/unicode/utf8-core.c
+++ b/fs/unicode/utf8-core.c@@ -6,6 +6,7 @@ #include <linux/parser.h> #include <linux/errno.h> #include <linux/unicode.h> +#include <linux/stringhash.h> #include "utf8n.h"
@@ -122,9 +123,29 @@ int utf8_casefold(const struct unicode_map *um, const struct qstr *str, } return -EINVAL; } - 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, unsigned char *dest, size_t dlen) {
diff --git a/include/linux/unicode.h b/include/linux/unicode.h
index 990aa97d80496..74484d44c7554 100644
--- a/include/linux/unicode.h
+++ b/include/linux/unicode.h@@ -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, 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); void utf8_unload(struct unicode_map *um);
--
2.25.1.481.gfbce0eb801-goog