glibc/string/strcasestr.c
Paul Eggert 5a82c74822 Prefer https to http for gnu.org and fsf.org URLs
Also, change sources.redhat.com to sourceware.org.
This patch was automatically generated by running the following shell
script, which uses GNU sed, and which avoids modifying files imported
from upstream:

sed -ri '
  s,(http|ftp)(://(.*\.)?(gnu|fsf|sourceware)\.org($|[^.]|\.[^a-z])),https\2,g
  s,(http|ftp)(://(.*\.)?)sources\.redhat\.com($|[^.]|\.[^a-z]),https\2sourceware.org\4,g
' \
  $(find $(git ls-files) -prune -type f \
      ! -name '*.po' \
      ! -name 'ChangeLog*' \
      ! -path COPYING ! -path COPYING.LIB \
      ! -path manual/fdl-1.3.texi ! -path manual/lgpl-2.1.texi \
      ! -path manual/texinfo.tex ! -path scripts/config.guess \
      ! -path scripts/config.sub ! -path scripts/install-sh \
      ! -path scripts/mkinstalldirs ! -path scripts/move-if-change \
      ! -path INSTALL ! -path  locale/programs/charmap-kw.h \
      ! -path po/libc.pot ! -path sysdeps/gnu/errlist.c \
      ! '(' -name configure \
            -execdir test -f configure.ac -o -f configure.in ';' ')' \
      ! '(' -name preconfigure \
            -execdir test -f preconfigure.ac ';' ')' \
      -print)

and then by running 'make dist-prepare' to regenerate files built
from the altered files, and then executing the following to cleanup:

  chmod a+x sysdeps/unix/sysv/linux/riscv/configure
  # Omit irrelevant whitespace and comment-only changes,
  # perhaps from a slightly-different Autoconf version.
  git checkout -f \
    sysdeps/csky/configure \
    sysdeps/hppa/configure \
    sysdeps/riscv/configure \
    sysdeps/unix/sysv/linux/csky/configure
  # Omit changes that caused a pre-commit check to fail like this:
  # remote: *** error: sysdeps/powerpc/powerpc64/ppc-mcount.S: trailing lines
  git checkout -f \
    sysdeps/powerpc/powerpc64/ppc-mcount.S \
    sysdeps/unix/sysv/linux/s390/s390-64/syscall.S
  # Omit change that caused a pre-commit check to fail like this:
  # remote: *** error: sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S: last line does not end in newline
  git checkout -f sysdeps/sparc/sparc64/multiarch/memcpy-ultra3.S
2019-09-07 02:43:31 -07:00

97 lines
3.2 KiB
C

/* Return the offset of one string within another.
Copyright (C) 1994-2019 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<https://www.gnu.org/licenses/>. */
/*
* My personal strstr() implementation that beats most other algorithms.
* Until someone tells me otherwise, I assume that this is the
* fastest implementation of strstr() in C.
* I deliberately chose not to comment it. You should have at least
* as much fun trying to understand it, as I had to write it :-).
*
* Stephen R. van den Berg, berg@pool.informatik.rwth-aachen.de */
/* Specification. */
#include <string.h>
#include <ctype.h>
#include <stdbool.h>
#include <strings.h>
#define TOLOWER(Ch) tolower (Ch)
/* Two-Way algorithm. */
#define RETURN_TYPE char *
#define AVAILABLE(h, h_l, j, n_l) \
(((j) + (n_l) <= (h_l)) \
|| ((h_l) += __strnlen ((void*)((h) + (h_l)), (n_l) + 512), \
(j) + (n_l) <= (h_l)))
#define CHECK_EOL (1)
#define RET0_IF_0(a) if (!a) goto ret0
#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"
#undef strcasestr
#undef __strcasestr
#ifndef STRCASESTR
#define STRCASESTR __strcasestr
#endif
/* 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)
{
size_t needle_len; /* Length of NEEDLE. */
size_t haystack_len; /* Known minimum length of HAYSTACK. */
/* Handle empty NEEDLE special case. */
if (needle[0] == '\0')
return (char *) haystack;
/* Ensure HAYSTACK length is at least as long as NEEDLE length.
Since a match may occur early on in a huge HAYSTACK, use strnlen
and read ahead a few cachelines for improved performance. */
needle_len = strlen (needle);
haystack_len = __strnlen (haystack, needle_len + 256);
if (haystack_len < needle_len)
return NULL;
/* 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,
needle_len);
return two_way_long_needle ((const unsigned char *) haystack, haystack_len,
(const unsigned char *) needle,
needle_len);
}
#undef LONG_NEEDLE_THRESHOLD
#ifndef NO_ALIAS
weak_alias (__strcasestr, strcasestr)
#endif