This function will allow other uses of unicode to act upon a casefolded string without needing to allocate their own copy of one. The actor function can return an nonzero value to exit early. Signed-off-by: Daniel Rosenberg <drosen@xxxxxxxxxx> --- fs/unicode/utf8-core.c | 25 ++++++++++++++++++++++++- include/linux/unicode.h | 10 ++++++++++ 2 files changed, 34 insertions(+), 1 deletion(-) diff --git a/fs/unicode/utf8-core.c b/fs/unicode/utf8-core.c index 2a878b739115d..db050bf59a32b 100644 --- a/fs/unicode/utf8-core.c +++ b/fs/unicode/utf8-core.c @@ -122,9 +122,32 @@ int utf8_casefold(const struct unicode_map *um, const struct qstr *str, } return -EINVAL; } - EXPORT_SYMBOL(utf8_casefold); +int utf8_casefold_iter(const struct unicode_map *um, const struct qstr *str, + struct utf8_itr_context *ctx) +{ + const struct utf8data *data = utf8nfdicf(um->version); + struct utf8cursor cur; + int c; + int res = 0; + int pos = 0; + + if (utf8ncursor(&cur, data, str->name, str->len) < 0) + return -EINVAL; + + while ((c = utf8byte(&cur))) { + if (c < 0) + return c; + res = ctx->actor(ctx, c, pos); + pos++; + if (res) + return res; + } + return res; +} +EXPORT_SYMBOL(utf8_casefold_iter); + 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..2ae12f8710ae2 100644 --- a/include/linux/unicode.h +++ b/include/linux/unicode.h @@ -10,6 +10,13 @@ struct unicode_map { int version; }; +struct utf8_itr_context; +typedef int (*utf8_itr_actor_t)(struct utf8_itr_context *, int byte, int pos); + +struct utf8_itr_context { + utf8_itr_actor_t actor; +}; + int utf8_validate(const struct unicode_map *um, const struct qstr *str); int utf8_strncmp(const struct unicode_map *um, @@ -27,6 +34,9 @@ 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_iter(const struct unicode_map *um, const struct qstr *str, + struct utf8_itr_context *ctx); + struct unicode_map *utf8_load(const char *version); void utf8_unload(struct unicode_map *um); -- 2.25.0.341.g760bfbb309-goog