X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=lib%2Fstrcasestr.c;h=3cca84ad67918b03c90949b783d9f8c77b4d671c;hb=23eecb48e39afd0d267d64d40ba6bf97aa865e13;hp=0a25f86f6b722cc3bc741f267d8bb4d1eaf64e54;hpb=c16199ce77b7fe5aee147446944e9ea27b431caa;p=gnulib.git diff --git a/lib/strcasestr.c b/lib/strcasestr.c index 0a25f86f6..3cca84ad6 100644 --- a/lib/strcasestr.c +++ b/lib/strcasestr.c @@ -1,5 +1,5 @@ /* Case-insensitive searching in a string. - Copyright (C) 2005-2007 Free Software Foundation, Inc. + Copyright (C) 2005-2013 Free Software Foundation, Inc. Written by Bruno Haible , 2005. This program is free software; you can redistribute it and/or modify @@ -13,8 +13,7 @@ GNU General Public License for more details. You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software Foundation, - Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ + along with this program; if not, see . */ #include @@ -22,124 +21,62 @@ #include #include -#include /* for NULL, in case a nonstandard string.h lacks it */ - -#if HAVE_MBRTOWC -# include "mbuiter.h" -#endif +#include +#include #define TOLOWER(Ch) (isupper (Ch) ? tolower (Ch) : (Ch)) -/* Find the first occurrence of NEEDLE in HAYSTACK, using case-insensitive - comparison. - Note: This function may, in multibyte locales, return success even if - strlen (haystack) < strlen (needle) ! */ +/* Two-Way algorithm. */ +#define RETURN_TYPE char * +#define AVAILABLE(h, h_l, j, n_l) \ + (!memchr ((h) + (h_l), '\0', (j) + (n_l) - (h_l)) \ + && ((h_l) = (j) + (n_l))) +#define CANON_ELEMENT(c) TOLOWER (c) +#define CMP_FUNC(p1, p2, l) \ + strncasecmp ((const char *) (p1), (const char *) (p2), l) +#include "str-two-way.h" + +/* Find the first occurrence of NEEDLE in HAYSTACK, using + case-insensitive comparison. This function gives unspecified + results in multibyte locales. */ char * -strcasestr (const char *haystack, const char *needle) +strcasestr (const char *haystack_start, const char *needle_start) { - /* Be careful not to look at the entire extent of haystack or needle - until needed. This is useful because of these two cases: - - haystack may be very long, and a match of needle found early, - - needle may be very long, and not even a short initial segment of - needle may be found in haystack. */ -#if HAVE_MBRTOWC - if (MB_CUR_MAX > 1) - { - mbui_iterator_t iter_needle; - - mbui_init (iter_needle, needle); - if (mbui_avail (iter_needle)) - { - mbchar_t b; - mbui_iterator_t iter_haystack; - - mb_copy (&b, &mbui_cur (iter_needle)); - if (b.wc_valid) - b.wc = towlower (b.wc); - - mbui_init (iter_haystack, haystack); - for (;; mbui_advance (iter_haystack)) - { - mbchar_t c; - - if (!mbui_avail (iter_haystack)) - /* No match. */ - return NULL; - - mb_copy (&c, &mbui_cur (iter_haystack)); - if (c.wc_valid) - c.wc = towlower (c.wc); - if (mb_equal (c, b)) - /* The first character matches. */ - { - mbui_iterator_t rhaystack; - mbui_iterator_t rneedle; - - memcpy (&rhaystack, &iter_haystack, sizeof (mbui_iterator_t)); - mbui_advance (rhaystack); - - mbui_init (rneedle, needle); - if (!mbui_avail (rneedle)) - abort (); - mbui_advance (rneedle); - - for (;; mbui_advance (rhaystack), mbui_advance (rneedle)) - { - if (!mbui_avail (rneedle)) - /* Found a match. */ - return (char *) mbui_cur_ptr (iter_haystack); - if (!mbui_avail (rhaystack)) - /* No match. */ - return NULL; - if (!mb_caseequal (mbui_cur (rhaystack), - mbui_cur (rneedle))) - /* Nothing in this round. */ - break; - } - } - } - } - else - return (char *) haystack; - } - else -#endif + const char *haystack = haystack_start; + const char *needle = needle_start; + size_t needle_len; /* Length of NEEDLE. */ + size_t haystack_len; /* Known minimum length of HAYSTACK. */ + bool ok = true; /* True if NEEDLE is prefix of HAYSTACK. */ + + /* Determine length of NEEDLE, and in the process, make sure + HAYSTACK is at least as long (no point processing all of a long + NEEDLE if HAYSTACK is too short). */ + while (*haystack && *needle) { - if (*needle != '\0') - { - /* Speed up the following searches of needle by caching its first - character. */ - unsigned char b = TOLOWER ((unsigned char) *needle); - - needle++; - for (;; haystack++) - { - if (*haystack == '\0') - /* No match. */ - return NULL; - if (TOLOWER ((unsigned char) *haystack) == b) - /* The first character matches. */ - { - const char *rhaystack = haystack + 1; - const char *rneedle = needle; - - for (;; rhaystack++, rneedle++) - { - if (*rneedle == '\0') - /* Found a match. */ - return (char *) haystack; - if (*rhaystack == '\0') - /* No match. */ - return NULL; - if (TOLOWER ((unsigned char) *rhaystack) - != TOLOWER ((unsigned char) *rneedle)) - /* Nothing in this round. */ - break; - } - } - } - } - else - return (char *) haystack; + ok &= (TOLOWER ((unsigned char) *haystack) + == TOLOWER ((unsigned char) *needle)); + haystack++; + needle++; } + if (*needle) + return NULL; + if (ok) + return (char *) haystack_start; + needle_len = needle - needle_start; + haystack = haystack_start + 1; + haystack_len = needle_len - 1; + + /* Perform the search. Abstract memory is considered to be an array + of 'unsigned char' values, not an array of 'char' values. See + ISO C 99 section 6.2.6.1. */ + if (needle_len < LONG_NEEDLE_THRESHOLD) + return two_way_short_needle ((const unsigned char *) haystack, + haystack_len, + (const unsigned char *) needle_start, + needle_len); + return two_way_long_needle ((const unsigned char *) haystack, haystack_len, + (const unsigned char *) needle_start, + needle_len); } + +#undef LONG_NEEDLE_THRESHOLD