diff options
Diffstat (limited to 'lib/unistr/u8-strstr.c')
-rw-r--r-- | lib/unistr/u8-strstr.c | 33 |
1 files changed, 24 insertions, 9 deletions
diff --git a/lib/unistr/u8-strstr.c b/lib/unistr/u8-strstr.c index 8b34c0a9..df2dc964 100644 --- a/lib/unistr/u8-strstr.c +++ b/lib/unistr/u8-strstr.c @@ -1,5 +1,5 @@ /* Substring test for UTF-8 strings. - Copyright (C) 1999, 2002, 2006, 2010-2022 Free Software Foundation, Inc. + Copyright (C) 1999, 2002, 2006, 2010-2024 Free Software Foundation, Inc. Written by Bruno Haible <bruno@clisp.org>, 2002. This file is free software. @@ -30,11 +30,26 @@ #include <string.h> -/* FIXME: Maybe walking the string via u8_mblen is a win? */ - -#define FUNC u8_strstr -#define UNIT uint8_t -#define U_STRCHR u8_strchr -#define U_STRMBTOUC u8_strmbtouc -#define UNIT_IS_UINT8_T 1 -#include "u-strstr.h" +uint8_t * +u8_strstr (const uint8_t *haystack, const uint8_t *needle) +{ + uint8_t first = needle[0]; + + /* Is needle empty? */ + if (first == 0) + return (uint8_t *) haystack; + + /* Is needle nearly empty (only one unit)? */ + if (needle[1] == 0) + return u8_strchr (haystack, first); + + /* Is needle nearly empty (only one character)? */ + { + ucs4_t first_uc; + int count = u8_strmbtouc (&first_uc, needle); + if (count > 0 && needle[count] == 0) + return u8_strchr (haystack, first_uc); + } + + return (uint8_t *) strstr ((const char *) haystack, (const char *) needle); +} |