Tune by using memchr and memrchr.

* .bzrignore: Add string.h.
* admin/merge-gnulib (GNULIB_MODULES): Add memrchr.
* lib/gnulib.mk, m4/gnulib-comp.m4: Regenerate.
* lib/memrchr.c, lib/string.in.h, m4/memrchr.m4, m4/string_h.m4:
New files, from gnulib.
* src/doc.c (Fsnarf_documentation):
* src/fileio.c (Fsubstitute_in_file_name):
* src/search.c (find_newline, scan_newline):
* src/xdisp.c (pos_visible_p, display_count_lines):
Use memchr and memrchr rather than scanning byte-by-byte.
* src/search.c (find_newline): Rename from scan_buffer.
Omit first arg TARGET, as it's always '\n'.  All callers changed.

1 files changed, 1029 insertions, 0 deletions

diff --git a/lib/string.in.h b/lib/string.in.h
new file mode 100644
index 00000000000..d7a6c9c923e
--- /dev/null
+++ b/lib/string.in.h
@@ -0,0 +1,1029 @@
+/* A GNU-like <string.h>.
+
+   Copyright (C) 1995-1996, 2001-2013 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3, or (at your option)
+   any later version.
+
+   This program 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 General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, see <http://www.gnu.org/licenses/>.  */
+
+#ifndef _@GUARD_PREFIX@_STRING_H
+
+#if __GNUC__ >= 3
+@PRAGMA_SYSTEM_HEADER@
+#endif
+@PRAGMA_COLUMNS@
+
+/* The include_next requires a split double-inclusion guard.  */
+#@INCLUDE_NEXT@ @NEXT_STRING_H@
+
+#ifndef _@GUARD_PREFIX@_STRING_H
+#define _@GUARD_PREFIX@_STRING_H
+
+/* NetBSD 5.0 mis-defines NULL.  */
+#include <stddef.h>
+
+/* MirBSD defines mbslen as a macro.  */
+#if @GNULIB_MBSLEN@ && defined __MirBSD__
+# include <wchar.h>
+#endif
+
+/* The __attribute__ feature is available in gcc versions 2.5 and later.
+   The attribute __pure__ was added in gcc 2.96.  */
+#if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 96)
+# define _GL_ATTRIBUTE_PURE __attribute__ ((__pure__))
+#else
+# define _GL_ATTRIBUTE_PURE /* empty */
+#endif
+
+/* NetBSD 5.0 declares strsignal in <unistd.h>, not in <string.h>.  */
+/* But in any case avoid namespace pollution on glibc systems.  */
+#if (@GNULIB_STRSIGNAL@ || defined GNULIB_POSIXCHECK) && defined __NetBSD__ \
+    && ! defined __GLIBC__
+# include <unistd.h>
+#endif
+
+/* The definitions of _GL_FUNCDECL_RPL etc. are copied here.  */
+
+/* The definition of _GL_ARG_NONNULL is copied here.  */
+
+/* The definition of _GL_WARN_ON_USE is copied here.  */
+
+
+/* Find the index of the least-significant set bit.  */
+#if @GNULIB_FFSL@
+# if !@HAVE_FFSL@
+_GL_FUNCDECL_SYS (ffsl, int, (long int i));
+# endif
+_GL_CXXALIAS_SYS (ffsl, int, (long int i));
+_GL_CXXALIASWARN (ffsl);
+#elif defined GNULIB_POSIXCHECK
+# undef ffsl
+# if HAVE_RAW_DECL_FFSL
+_GL_WARN_ON_USE (ffsl, "ffsl is not portable - use the ffsl module");
+# endif
+#endif
+
+
+/* Find the index of the least-significant set bit.  */
+#if @GNULIB_FFSLL@
+# if !@HAVE_FFSLL@
+_GL_FUNCDECL_SYS (ffsll, int, (long long int i));
+# endif
+_GL_CXXALIAS_SYS (ffsll, int, (long long int i));
+_GL_CXXALIASWARN (ffsll);
+#elif defined GNULIB_POSIXCHECK
+# undef ffsll
+# if HAVE_RAW_DECL_FFSLL
+_GL_WARN_ON_USE (ffsll, "ffsll is not portable - use the ffsll module");
+# endif
+#endif
+
+
+/* Return the first instance of C within N bytes of S, or NULL.  */
+#if @GNULIB_MEMCHR@
+# if @REPLACE_MEMCHR@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define memchr rpl_memchr
+#  endif
+_GL_FUNCDECL_RPL (memchr, void *, (void const *__s, int __c, size_t __n)
+                                  _GL_ATTRIBUTE_PURE
+                                  _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_RPL (memchr, void *, (void const *__s, int __c, size_t __n));
+# else
+#  if ! @HAVE_MEMCHR@
+_GL_FUNCDECL_SYS (memchr, void *, (void const *__s, int __c, size_t __n)
+                                  _GL_ATTRIBUTE_PURE
+                                  _GL_ARG_NONNULL ((1)));
+#  endif
+  /* On some systems, this function is defined as an overloaded function:
+       extern "C" { const void * std::memchr (const void *, int, size_t); }
+       extern "C++" { void * std::memchr (void *, int, size_t); }  */
+_GL_CXXALIAS_SYS_CAST2 (memchr,
+                        void *, (void const *__s, int __c, size_t __n),
+                        void const *, (void const *__s, int __c, size_t __n));
+# endif
+# if ((__GLIBC__ == 2 && __GLIBC_MINOR__ >= 10) && !defined __UCLIBC__) \
+     && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4))
+_GL_CXXALIASWARN1 (memchr, void *, (void *__s, int __c, size_t __n));
+_GL_CXXALIASWARN1 (memchr, void const *,
+                   (void const *__s, int __c, size_t __n));
+# else
+_GL_CXXALIASWARN (memchr);
+# endif
+#elif defined GNULIB_POSIXCHECK
+# undef memchr
+/* Assume memchr is always declared.  */
+_GL_WARN_ON_USE (memchr, "memchr has platform-specific bugs - "
+                 "use gnulib module memchr for portability" );
+#endif
+
+/* Return the first occurrence of NEEDLE in HAYSTACK.  */
+#if @GNULIB_MEMMEM@
+# if @REPLACE_MEMMEM@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define memmem rpl_memmem
+#  endif
+_GL_FUNCDECL_RPL (memmem, void *,
+                  (void const *__haystack, size_t __haystack_len,
+                   void const *__needle, size_t __needle_len)
+                  _GL_ATTRIBUTE_PURE
+                  _GL_ARG_NONNULL ((1, 3)));
+_GL_CXXALIAS_RPL (memmem, void *,
+                  (void const *__haystack, size_t __haystack_len,
+                   void const *__needle, size_t __needle_len));
+# else
+#  if ! @HAVE_DECL_MEMMEM@
+_GL_FUNCDECL_SYS (memmem, void *,
+                  (void const *__haystack, size_t __haystack_len,
+                   void const *__needle, size_t __needle_len)
+                  _GL_ATTRIBUTE_PURE
+                  _GL_ARG_NONNULL ((1, 3)));
+#  endif
+_GL_CXXALIAS_SYS (memmem, void *,
+                  (void const *__haystack, size_t __haystack_len,
+                   void const *__needle, size_t __needle_len));
+# endif
+_GL_CXXALIASWARN (memmem);
+#elif defined GNULIB_POSIXCHECK
+# undef memmem
+# if HAVE_RAW_DECL_MEMMEM
+_GL_WARN_ON_USE (memmem, "memmem is unportable and often quadratic - "
+                 "use gnulib module memmem-simple for portability, "
+                 "and module memmem for speed" );
+# endif
+#endif
+
+/* Copy N bytes of SRC to DEST, return pointer to bytes after the
+   last written byte.  */
+#if @GNULIB_MEMPCPY@
+# if ! @HAVE_MEMPCPY@
+_GL_FUNCDECL_SYS (mempcpy, void *,
+                  (void *restrict __dest, void const *restrict __src,
+                   size_t __n)
+                  _GL_ARG_NONNULL ((1, 2)));
+# endif
+_GL_CXXALIAS_SYS (mempcpy, void *,
+                  (void *restrict __dest, void const *restrict __src,
+                   size_t __n));
+_GL_CXXALIASWARN (mempcpy);
+#elif defined GNULIB_POSIXCHECK
+# undef mempcpy
+# if HAVE_RAW_DECL_MEMPCPY
+_GL_WARN_ON_USE (mempcpy, "mempcpy is unportable - "
+                 "use gnulib module mempcpy for portability");
+# endif
+#endif
+
+/* Search backwards through a block for a byte (specified as an int).  */
+#if @GNULIB_MEMRCHR@
+# if ! @HAVE_DECL_MEMRCHR@
+_GL_FUNCDECL_SYS (memrchr, void *, (void const *, int, size_t)
+                                   _GL_ATTRIBUTE_PURE
+                                   _GL_ARG_NONNULL ((1)));
+# endif
+  /* On some systems, this function is defined as an overloaded function:
+       extern "C++" { const void * std::memrchr (const void *, int, size_t); }
+       extern "C++" { void * std::memrchr (void *, int, size_t); }  */
+_GL_CXXALIAS_SYS_CAST2 (memrchr,
+                        void *, (void const *, int, size_t),
+                        void const *, (void const *, int, size_t));
+# if ((__GLIBC__ == 2 && __GLIBC_MINOR__ >= 10) && !defined __UCLIBC__) \
+     && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4))
+_GL_CXXALIASWARN1 (memrchr, void *, (void *, int, size_t));
+_GL_CXXALIASWARN1 (memrchr, void const *, (void const *, int, size_t));
+# else
+_GL_CXXALIASWARN (memrchr);
+# endif
+#elif defined GNULIB_POSIXCHECK
+# undef memrchr
+# if HAVE_RAW_DECL_MEMRCHR
+_GL_WARN_ON_USE (memrchr, "memrchr is unportable - "
+                 "use gnulib module memrchr for portability");
+# endif
+#endif
+
+/* Find the first occurrence of C in S.  More efficient than
+   memchr(S,C,N), at the expense of undefined behavior if C does not
+   occur within N bytes.  */
+#if @GNULIB_RAWMEMCHR@
+# if ! @HAVE_RAWMEMCHR@
+_GL_FUNCDECL_SYS (rawmemchr, void *, (void const *__s, int __c_in)
+                                     _GL_ATTRIBUTE_PURE
+                                     _GL_ARG_NONNULL ((1)));
+# endif
+  /* On some systems, this function is defined as an overloaded function:
+       extern "C++" { const void * std::rawmemchr (const void *, int); }
+       extern "C++" { void * std::rawmemchr (void *, int); }  */
+_GL_CXXALIAS_SYS_CAST2 (rawmemchr,
+                        void *, (void const *__s, int __c_in),
+                        void const *, (void const *__s, int __c_in));
+# if ((__GLIBC__ == 2 && __GLIBC_MINOR__ >= 10) && !defined __UCLIBC__) \
+     && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4))
+_GL_CXXALIASWARN1 (rawmemchr, void *, (void *__s, int __c_in));
+_GL_CXXALIASWARN1 (rawmemchr, void const *, (void const *__s, int __c_in));
+# else
+_GL_CXXALIASWARN (rawmemchr);
+# endif
+#elif defined GNULIB_POSIXCHECK
+# undef rawmemchr
+# if HAVE_RAW_DECL_RAWMEMCHR
+_GL_WARN_ON_USE (rawmemchr, "rawmemchr is unportable - "
+                 "use gnulib module rawmemchr for portability");
+# endif
+#endif
+
+/* Copy SRC to DST, returning the address of the terminating '\0' in DST.  */
+#if @GNULIB_STPCPY@
+# if ! @HAVE_STPCPY@
+_GL_FUNCDECL_SYS (stpcpy, char *,
+                  (char *restrict __dst, char const *restrict __src)
+                  _GL_ARG_NONNULL ((1, 2)));
+# endif
+_GL_CXXALIAS_SYS (stpcpy, char *,
+                  (char *restrict __dst, char const *restrict __src));
+_GL_CXXALIASWARN (stpcpy);
+#elif defined GNULIB_POSIXCHECK
+# undef stpcpy
+# if HAVE_RAW_DECL_STPCPY
+_GL_WARN_ON_USE (stpcpy, "stpcpy is unportable - "
+                 "use gnulib module stpcpy for portability");
+# endif
+#endif
+
+/* Copy no more than N bytes of SRC to DST, returning a pointer past the
+   last non-NUL byte written into DST.  */
+#if @GNULIB_STPNCPY@
+# if @REPLACE_STPNCPY@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef stpncpy
+#   define stpncpy rpl_stpncpy
+#  endif
+_GL_FUNCDECL_RPL (stpncpy, char *,
+                  (char *restrict __dst, char const *restrict __src,
+                   size_t __n)
+                  _GL_ARG_NONNULL ((1, 2)));
+_GL_CXXALIAS_RPL (stpncpy, char *,
+                  (char *restrict __dst, char const *restrict __src,
+                   size_t __n));
+# else
+#  if ! @HAVE_STPNCPY@
+_GL_FUNCDECL_SYS (stpncpy, char *,
+                  (char *restrict __dst, char const *restrict __src,
+                   size_t __n)
+                  _GL_ARG_NONNULL ((1, 2)));
+#  endif
+_GL_CXXALIAS_SYS (stpncpy, char *,
+                  (char *restrict __dst, char const *restrict __src,
+                   size_t __n));
+# endif
+_GL_CXXALIASWARN (stpncpy);
+#elif defined GNULIB_POSIXCHECK
+# undef stpncpy
+# if HAVE_RAW_DECL_STPNCPY
+_GL_WARN_ON_USE (stpncpy, "stpncpy is unportable - "
+                 "use gnulib module stpncpy for portability");
+# endif
+#endif
+
+#if defined GNULIB_POSIXCHECK
+/* strchr() does not work with multibyte strings if the locale encoding is
+   GB18030 and the character to be searched is a digit.  */
+# undef strchr
+/* Assume strchr is always declared.  */
+_GL_WARN_ON_USE (strchr, "strchr cannot work correctly on character strings "
+                 "in some multibyte locales - "
+                 "use mbschr if you care about internationalization");
+#endif
+
+/* Find the first occurrence of C in S or the final NUL byte.  */
+#if @GNULIB_STRCHRNUL@
+# if @REPLACE_STRCHRNUL@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define strchrnul rpl_strchrnul
+#  endif
+_GL_FUNCDECL_RPL (strchrnul, char *, (const char *__s, int __c_in)
+                                     _GL_ATTRIBUTE_PURE
+                                     _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_RPL (strchrnul, char *,
+                  (const char *str, int ch));
+# else
+#  if ! @HAVE_STRCHRNUL@
+_GL_FUNCDECL_SYS (strchrnul, char *, (char const *__s, int __c_in)
+                                     _GL_ATTRIBUTE_PURE
+                                     _GL_ARG_NONNULL ((1)));
+#  endif
+  /* On some systems, this function is defined as an overloaded function:
+       extern "C++" { const char * std::strchrnul (const char *, int); }
+       extern "C++" { char * std::strchrnul (char *, int); }  */
+_GL_CXXALIAS_SYS_CAST2 (strchrnul,
+                        char *, (char const *__s, int __c_in),
+                        char const *, (char const *__s, int __c_in));
+# endif
+# if ((__GLIBC__ == 2 && __GLIBC_MINOR__ >= 10) && !defined __UCLIBC__) \
+     && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4))
+_GL_CXXALIASWARN1 (strchrnul, char *, (char *__s, int __c_in));
+_GL_CXXALIASWARN1 (strchrnul, char const *, (char const *__s, int __c_in));
+# else
+_GL_CXXALIASWARN (strchrnul);
+# endif
+#elif defined GNULIB_POSIXCHECK
+# undef strchrnul
+# if HAVE_RAW_DECL_STRCHRNUL
+_GL_WARN_ON_USE (strchrnul, "strchrnul is unportable - "
+                 "use gnulib module strchrnul for portability");
+# endif
+#endif
+
+/* Duplicate S, returning an identical malloc'd string.  */
+#if @GNULIB_STRDUP@
+# if @REPLACE_STRDUP@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef strdup
+#   define strdup rpl_strdup
+#  endif
+_GL_FUNCDECL_RPL (strdup, char *, (char const *__s) _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_RPL (strdup, char *, (char const *__s));
+# else
+#  if defined __cplusplus && defined GNULIB_NAMESPACE && defined strdup
+    /* strdup exists as a function and as a macro.  Get rid of the macro.  */
+#   undef strdup
+#  endif
+#  if !(@HAVE_DECL_STRDUP@ || defined strdup)
+_GL_FUNCDECL_SYS (strdup, char *, (char const *__s) _GL_ARG_NONNULL ((1)));
+#  endif
+_GL_CXXALIAS_SYS (strdup, char *, (char const *__s));
+# endif
+_GL_CXXALIASWARN (strdup);
+#elif defined GNULIB_POSIXCHECK
+# undef strdup
+# if HAVE_RAW_DECL_STRDUP
+_GL_WARN_ON_USE (strdup, "strdup is unportable - "
+                 "use gnulib module strdup for portability");
+# endif
+#endif
+
+/* Append no more than N characters from SRC onto DEST.  */
+#if @GNULIB_STRNCAT@
+# if @REPLACE_STRNCAT@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef strncat
+#   define strncat rpl_strncat
+#  endif
+_GL_FUNCDECL_RPL (strncat, char *, (char *dest, const char *src, size_t n)
+                                   _GL_ARG_NONNULL ((1, 2)));
+_GL_CXXALIAS_RPL (strncat, char *, (char *dest, const char *src, size_t n));
+# else
+_GL_CXXALIAS_SYS (strncat, char *, (char *dest, const char *src, size_t n));
+# endif
+_GL_CXXALIASWARN (strncat);
+#elif defined GNULIB_POSIXCHECK
+# undef strncat
+# if HAVE_RAW_DECL_STRNCAT
+_GL_WARN_ON_USE (strncat, "strncat is unportable - "
+                 "use gnulib module strncat for portability");
+# endif
+#endif
+
+/* Return a newly allocated copy of at most N bytes of STRING.  */
+#if @GNULIB_STRNDUP@
+# if @REPLACE_STRNDUP@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef strndup
+#   define strndup rpl_strndup
+#  endif
+_GL_FUNCDECL_RPL (strndup, char *, (char const *__string, size_t __n)
+                                   _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_RPL (strndup, char *, (char const *__string, size_t __n));
+# else
+#  if ! @HAVE_DECL_STRNDUP@
+_GL_FUNCDECL_SYS (strndup, char *, (char const *__string, size_t __n)
+                                   _GL_ARG_NONNULL ((1)));
+#  endif
+_GL_CXXALIAS_SYS (strndup, char *, (char const *__string, size_t __n));
+# endif
+_GL_CXXALIASWARN (strndup);
+#elif defined GNULIB_POSIXCHECK
+# undef strndup
+# if HAVE_RAW_DECL_STRNDUP
+_GL_WARN_ON_USE (strndup, "strndup is unportable - "
+                 "use gnulib module strndup for portability");
+# endif
+#endif
+
+/* Find the length (number of bytes) of STRING, but scan at most
+   MAXLEN bytes.  If no '\0' terminator is found in that many bytes,
+   return MAXLEN.  */
+#if @GNULIB_STRNLEN@
+# if @REPLACE_STRNLEN@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef strnlen
+#   define strnlen rpl_strnlen
+#  endif
+_GL_FUNCDECL_RPL (strnlen, size_t, (char const *__string, size_t __maxlen)
+                                   _GL_ATTRIBUTE_PURE
+                                   _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_RPL (strnlen, size_t, (char const *__string, size_t __maxlen));
+# else
+#  if ! @HAVE_DECL_STRNLEN@
+_GL_FUNCDECL_SYS (strnlen, size_t, (char const *__string, size_t __maxlen)
+                                   _GL_ATTRIBUTE_PURE
+                                   _GL_ARG_NONNULL ((1)));
+#  endif
+_GL_CXXALIAS_SYS (strnlen, size_t, (char const *__string, size_t __maxlen));
+# endif
+_GL_CXXALIASWARN (strnlen);
+#elif defined GNULIB_POSIXCHECK
+# undef strnlen
+# if HAVE_RAW_DECL_STRNLEN
+_GL_WARN_ON_USE (strnlen, "strnlen is unportable - "
+                 "use gnulib module strnlen for portability");
+# endif
+#endif
+
+#if defined GNULIB_POSIXCHECK
+/* strcspn() assumes the second argument is a list of single-byte characters.
+   Even in this simple case, it does not work with multibyte strings if the
+   locale encoding is GB18030 and one of the characters to be searched is a
+   digit.  */
+# undef strcspn
+/* Assume strcspn is always declared.  */
+_GL_WARN_ON_USE (strcspn, "strcspn cannot work correctly on character strings "
+                 "in multibyte locales - "
+                 "use mbscspn if you care about internationalization");
+#endif
+
+/* Find the first occurrence in S of any character in ACCEPT.  */
+#if @GNULIB_STRPBRK@
+# if ! @HAVE_STRPBRK@
+_GL_FUNCDECL_SYS (strpbrk, char *, (char const *__s, char const *__accept)
+                                   _GL_ATTRIBUTE_PURE
+                                   _GL_ARG_NONNULL ((1, 2)));
+# endif
+  /* On some systems, this function is defined as an overloaded function:
+       extern "C" { const char * strpbrk (const char *, const char *); }
+       extern "C++" { char * strpbrk (char *, const char *); }  */
+_GL_CXXALIAS_SYS_CAST2 (strpbrk,
+                        char *, (char const *__s, char const *__accept),
+                        const char *, (char const *__s, char const *__accept));
+# if ((__GLIBC__ == 2 && __GLIBC_MINOR__ >= 10) && !defined __UCLIBC__) \
+     && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4))
+_GL_CXXALIASWARN1 (strpbrk, char *, (char *__s, char const *__accept));
+_GL_CXXALIASWARN1 (strpbrk, char const *,
+                   (char const *__s, char const *__accept));
+# else
+_GL_CXXALIASWARN (strpbrk);
+# endif
+# if defined GNULIB_POSIXCHECK
+/* strpbrk() assumes the second argument is a list of single-byte characters.
+   Even in this simple case, it does not work with multibyte strings if the
+   locale encoding is GB18030 and one of the characters to be searched is a
+   digit.  */
+#  undef strpbrk
+_GL_WARN_ON_USE (strpbrk, "strpbrk cannot work correctly on character strings "
+                 "in multibyte locales - "
+                 "use mbspbrk if you care about internationalization");
+# endif
+#elif defined GNULIB_POSIXCHECK
+# undef strpbrk
+# if HAVE_RAW_DECL_STRPBRK
+_GL_WARN_ON_USE (strpbrk, "strpbrk is unportable - "
+                 "use gnulib module strpbrk for portability");
+# endif
+#endif
+
+#if defined GNULIB_POSIXCHECK
+/* strspn() assumes the second argument is a list of single-byte characters.
+   Even in this simple case, it cannot work with multibyte strings.  */
+# undef strspn
+/* Assume strspn is always declared.  */
+_GL_WARN_ON_USE (strspn, "strspn cannot work correctly on character strings "
+                 "in multibyte locales - "
+                 "use mbsspn if you care about internationalization");
+#endif
+
+#if defined GNULIB_POSIXCHECK
+/* strrchr() does not work with multibyte strings if the locale encoding is
+   GB18030 and the character to be searched is a digit.  */
+# undef strrchr
+/* Assume strrchr is always declared.  */
+_GL_WARN_ON_USE (strrchr, "strrchr cannot work correctly on character strings "
+                 "in some multibyte locales - "
+                 "use mbsrchr if you care about internationalization");
+#endif
+
+/* Search the next delimiter (char listed in DELIM) starting at *STRINGP.
+   If one is found, overwrite it with a NUL, and advance *STRINGP
+   to point to the next char after it.  Otherwise, set *STRINGP to NULL.
+   If *STRINGP was already NULL, nothing happens.
+   Return the old value of *STRINGP.
+
+   This is a variant of strtok() that is multithread-safe and supports
+   empty fields.
+
+   Caveat: It modifies the original string.
+   Caveat: These functions cannot be used on constant strings.
+   Caveat: The identity of the delimiting character is lost.
+   Caveat: It doesn't work with multibyte strings unless all of the delimiter
+           characters are ASCII characters < 0x30.
+
+   See also strtok_r().  */
+#if @GNULIB_STRSEP@
+# if ! @HAVE_STRSEP@
+_GL_FUNCDECL_SYS (strsep, char *,
+                  (char **restrict __stringp, char const *restrict __delim)
+                  _GL_ARG_NONNULL ((1, 2)));
+# endif
+_GL_CXXALIAS_SYS (strsep, char *,
+                  (char **restrict __stringp, char const *restrict __delim));
+_GL_CXXALIASWARN (strsep);
+# if defined GNULIB_POSIXCHECK
+#  undef strsep
+_GL_WARN_ON_USE (strsep, "strsep cannot work correctly on character strings "
+                 "in multibyte locales - "
+                 "use mbssep if you care about internationalization");
+# endif
+#elif defined GNULIB_POSIXCHECK
+# undef strsep
+# if HAVE_RAW_DECL_STRSEP
+_GL_WARN_ON_USE (strsep, "strsep is unportable - "
+                 "use gnulib module strsep for portability");
+# endif
+#endif
+
+#if @GNULIB_STRSTR@
+# if @REPLACE_STRSTR@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define strstr rpl_strstr
+#  endif
+_GL_FUNCDECL_RPL (strstr, char *, (const char *haystack, const char *needle)
+                                  _GL_ATTRIBUTE_PURE
+                                  _GL_ARG_NONNULL ((1, 2)));
+_GL_CXXALIAS_RPL (strstr, char *, (const char *haystack, const char *needle));
+# else
+  /* On some systems, this function is defined as an overloaded function:
+       extern "C++" { const char * strstr (const char *, const char *); }
+       extern "C++" { char * strstr (char *, const char *); }  */
+_GL_CXXALIAS_SYS_CAST2 (strstr,
+                        char *, (const char *haystack, const char *needle),
+                        const char *, (const char *haystack, const char *needle));
+# endif
+# if ((__GLIBC__ == 2 && __GLIBC_MINOR__ >= 10) && !defined __UCLIBC__) \
+     && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4))
+_GL_CXXALIASWARN1 (strstr, char *, (char *haystack, const char *needle));
+_GL_CXXALIASWARN1 (strstr, const char *,
+                   (const char *haystack, const char *needle));
+# else
+_GL_CXXALIASWARN (strstr);
+# endif
+#elif defined GNULIB_POSIXCHECK
+/* strstr() does not work with multibyte strings if the locale encoding is
+   different from UTF-8:
+   POSIX says that it operates on "strings", and "string" in POSIX is defined
+   as a sequence of bytes, not of characters.  */
+# undef strstr
+/* Assume strstr is always declared.  */
+_GL_WARN_ON_USE (strstr, "strstr is quadratic on many systems, and cannot "
+                 "work correctly on character strings in most "
+                 "multibyte locales - "
+                 "use mbsstr if you care about internationalization, "
+                 "or use strstr if you care about speed");
+#endif
+
+/* Find the first occurrence of NEEDLE in HAYSTACK, using case-insensitive
+   comparison.  */
+#if @GNULIB_STRCASESTR@
+# if @REPLACE_STRCASESTR@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define strcasestr rpl_strcasestr
+#  endif
+_GL_FUNCDECL_RPL (strcasestr, char *,
+                  (const char *haystack, const char *needle)
+                  _GL_ATTRIBUTE_PURE
+                  _GL_ARG_NONNULL ((1, 2)));
+_GL_CXXALIAS_RPL (strcasestr, char *,
+                  (const char *haystack, const char *needle));
+# else
+#  if ! @HAVE_STRCASESTR@
+_GL_FUNCDECL_SYS (strcasestr, char *,
+                  (const char *haystack, const char *needle)
+                  _GL_ATTRIBUTE_PURE
+                  _GL_ARG_NONNULL ((1, 2)));
+#  endif
+  /* On some systems, this function is defined as an overloaded function:
+       extern "C++" { const char * strcasestr (const char *, const char *); }
+       extern "C++" { char * strcasestr (char *, const char *); }  */
+_GL_CXXALIAS_SYS_CAST2 (strcasestr,
+                        char *, (const char *haystack, const char *needle),
+                        const char *, (const char *haystack, const char *needle));
+# endif
+# if ((__GLIBC__ == 2 && __GLIBC_MINOR__ >= 10) && !defined __UCLIBC__) \
+     && (__GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 4))
+_GL_CXXALIASWARN1 (strcasestr, char *, (char *haystack, const char *needle));
+_GL_CXXALIASWARN1 (strcasestr, const char *,
+                   (const char *haystack, const char *needle));
+# else
+_GL_CXXALIASWARN (strcasestr);
+# endif
+#elif defined GNULIB_POSIXCHECK
+/* strcasestr() does not work with multibyte strings:
+   It is a glibc extension, and glibc implements it only for unibyte
+   locales.  */
+# undef strcasestr
+# if HAVE_RAW_DECL_STRCASESTR
+_GL_WARN_ON_USE (strcasestr, "strcasestr does work correctly on character "
+                 "strings in multibyte locales - "
+                 "use mbscasestr if you care about "
+                 "internationalization, or use c-strcasestr if you want "
+                 "a locale independent function");
+# endif
+#endif
+
+/* Parse S into tokens separated by characters in DELIM.
+   If S is NULL, the saved pointer in SAVE_PTR is used as
+   the next starting point.  For example:
+        char s[] = "-abc-=-def";
+        char *sp;
+        x = strtok_r(s, "-", &sp);      // x = "abc", sp = "=-def"
+        x = strtok_r(NULL, "-=", &sp);  // x = "def", sp = NULL
+        x = strtok_r(NULL, "=", &sp);   // x = NULL
+                // s = "abc\0-def\0"
+
+   This is a variant of strtok() that is multithread-safe.
+
+   For the POSIX documentation for this function, see:
+   http://www.opengroup.org/susv3xsh/strtok.html
+
+   Caveat: It modifies the original string.
+   Caveat: These functions cannot be used on constant strings.
+   Caveat: The identity of the delimiting character is lost.
+   Caveat: It doesn't work with multibyte strings unless all of the delimiter
+           characters are ASCII characters < 0x30.
+
+   See also strsep().  */
+#if @GNULIB_STRTOK_R@
+# if @REPLACE_STRTOK_R@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef strtok_r
+#   define strtok_r rpl_strtok_r
+#  endif
+_GL_FUNCDECL_RPL (strtok_r, char *,
+                  (char *restrict s, char const *restrict delim,
+                   char **restrict save_ptr)
+                  _GL_ARG_NONNULL ((2, 3)));
+_GL_CXXALIAS_RPL (strtok_r, char *,
+                  (char *restrict s, char const *restrict delim,
+                   char **restrict save_ptr));
+# else
+#  if @UNDEFINE_STRTOK_R@ || defined GNULIB_POSIXCHECK
+#   undef strtok_r
+#  endif
+#  if ! @HAVE_DECL_STRTOK_R@
+_GL_FUNCDECL_SYS (strtok_r, char *,
+                  (char *restrict s, char const *restrict delim,
+                   char **restrict save_ptr)
+                  _GL_ARG_NONNULL ((2, 3)));
+#  endif
+_GL_CXXALIAS_SYS (strtok_r, char *,
+                  (char *restrict s, char const *restrict delim,
+                   char **restrict save_ptr));
+# endif
+_GL_CXXALIASWARN (strtok_r);
+# if defined GNULIB_POSIXCHECK
+_GL_WARN_ON_USE (strtok_r, "strtok_r cannot work correctly on character "
+                 "strings in multibyte locales - "
+                 "use mbstok_r if you care about internationalization");
+# endif
+#elif defined GNULIB_POSIXCHECK
+# undef strtok_r
+# if HAVE_RAW_DECL_STRTOK_R
+_GL_WARN_ON_USE (strtok_r, "strtok_r is unportable - "
+                 "use gnulib module strtok_r for portability");
+# endif
+#endif
+
+
+/* The following functions are not specified by POSIX.  They are gnulib
+   extensions.  */
+
+#if @GNULIB_MBSLEN@
+/* Return the number of multibyte characters in the character string STRING.
+   This considers multibyte characters, unlike strlen, which counts bytes.  */
+# ifdef __MirBSD__  /* MirBSD defines mbslen as a macro.  Override it.  */
+#  undef mbslen
+# endif
+# if @HAVE_MBSLEN@  /* AIX, OSF/1, MirBSD define mbslen already in libc.  */
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define mbslen rpl_mbslen
+#  endif
+_GL_FUNCDECL_RPL (mbslen, size_t, (const char *string)
+                                  _GL_ATTRIBUTE_PURE
+                                  _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_RPL (mbslen, size_t, (const char *string));
+# else
+_GL_FUNCDECL_SYS (mbslen, size_t, (const char *string)
+                                  _GL_ATTRIBUTE_PURE
+                                  _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_SYS (mbslen, size_t, (const char *string));
+# endif
+_GL_CXXALIASWARN (mbslen);
+#endif
+
+#if @GNULIB_MBSNLEN@
+/* Return the number of multibyte characters in the character string starting
+   at STRING and ending at STRING + LEN.  */
+_GL_EXTERN_C size_t mbsnlen (const char *string, size_t len)
+     _GL_ATTRIBUTE_PURE
+     _GL_ARG_NONNULL ((1));
+#endif
+
+#if @GNULIB_MBSCHR@
+/* Locate the first single-byte character C in the character string STRING,
+   and return a pointer to it.  Return NULL if C is not found in STRING.
+   Unlike strchr(), this function works correctly in multibyte locales with
+   encodings such as GB18030.  */
+# if defined __hpux
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define mbschr rpl_mbschr /* avoid collision with HP-UX function */
+#  endif
+_GL_FUNCDECL_RPL (mbschr, char *, (const char *string, int c)
+                                  _GL_ATTRIBUTE_PURE
+                                  _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_RPL (mbschr, char *, (const char *string, int c));
+# else
+_GL_FUNCDECL_SYS (mbschr, char *, (const char *string, int c)
+                                  _GL_ATTRIBUTE_PURE
+                                  _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_SYS (mbschr, char *, (const char *string, int c));
+# endif
+_GL_CXXALIASWARN (mbschr);
+#endif
+
+#if @GNULIB_MBSRCHR@
+/* Locate the last single-byte character C in the character string STRING,
+   and return a pointer to it.  Return NULL if C is not found in STRING.
+   Unlike strrchr(), this function works correctly in multibyte locales with
+   encodings such as GB18030.  */
+# if defined __hpux || defined __INTERIX
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define mbsrchr rpl_mbsrchr /* avoid collision with system function */
+#  endif
+_GL_FUNCDECL_RPL (mbsrchr, char *, (const char *string, int c)
+                                   _GL_ATTRIBUTE_PURE
+                                   _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_RPL (mbsrchr, char *, (const char *string, int c));
+# else
+_GL_FUNCDECL_SYS (mbsrchr, char *, (const char *string, int c)
+                                   _GL_ATTRIBUTE_PURE
+                                   _GL_ARG_NONNULL ((1)));
+_GL_CXXALIAS_SYS (mbsrchr, char *, (const char *string, int c));
+# endif
+_GL_CXXALIASWARN (mbsrchr);
+#endif
+
+#if @GNULIB_MBSSTR@
+/* Find the first occurrence of the character string NEEDLE in the character
+   string HAYSTACK.  Return NULL if NEEDLE is not found in HAYSTACK.
+   Unlike strstr(), this function works correctly in multibyte locales with
+   encodings different from UTF-8.  */
+_GL_EXTERN_C char * mbsstr (const char *haystack, const char *needle)
+     _GL_ATTRIBUTE_PURE
+     _GL_ARG_NONNULL ((1, 2));
+#endif
+
+#if @GNULIB_MBSCASECMP@
+/* Compare the character strings S1 and S2, ignoring case, returning less than,
+   equal to or greater than zero if S1 is lexicographically less than, equal to
+   or greater than S2.
+   Note: This function may, in multibyte locales, return 0 for strings of
+   different lengths!
+   Unlike strcasecmp(), this function works correctly in multibyte locales.  */
+_GL_EXTERN_C int mbscasecmp (const char *s1, const char *s2)
+     _GL_ATTRIBUTE_PURE
+     _GL_ARG_NONNULL ((1, 2));
+#endif
+
+#if @GNULIB_MBSNCASECMP@
+/* Compare the initial segment of the character string S1 consisting of at most
+   N characters with the initial segment of the character string S2 consisting
+   of at most N characters, ignoring case, returning less than, equal to or
+   greater than zero if the initial segment of S1 is lexicographically less
+   than, equal to or greater than the initial segment of S2.
+   Note: This function may, in multibyte locales, return 0 for initial segments
+   of different lengths!
+   Unlike strncasecmp(), this function works correctly in multibyte locales.
+   But beware that N is not a byte count but a character count!  */
+_GL_EXTERN_C int mbsncasecmp (const char *s1, const char *s2, size_t n)
+     _GL_ATTRIBUTE_PURE
+     _GL_ARG_NONNULL ((1, 2));
+#endif
+
+#if @GNULIB_MBSPCASECMP@
+/* Compare the initial segment of the character string STRING consisting of
+   at most mbslen (PREFIX) characters with the character string PREFIX,
+   ignoring case.  If the two match, return a pointer to the first byte
+   after this prefix in STRING.  Otherwise, return NULL.
+   Note: This function may, in multibyte locales, return non-NULL if STRING
+   is of smaller length than PREFIX!
+   Unlike strncasecmp(), this function works correctly in multibyte
+   locales.  */
+_GL_EXTERN_C char * mbspcasecmp (const char *string, const char *prefix)
+     _GL_ATTRIBUTE_PURE
+     _GL_ARG_NONNULL ((1, 2));
+#endif
+
+#if @GNULIB_MBSCASESTR@
+/* Find the first occurrence of the character string NEEDLE in the character
+   string HAYSTACK, using case-insensitive comparison.
+   Note: This function may, in multibyte locales, return success even if
+   strlen (haystack) < strlen (needle) !
+   Unlike strcasestr(), this function works correctly in multibyte locales.  */
+_GL_EXTERN_C char * mbscasestr (const char *haystack, const char *needle)
+     _GL_ATTRIBUTE_PURE
+     _GL_ARG_NONNULL ((1, 2));
+#endif
+
+#if @GNULIB_MBSCSPN@
+/* Find the first occurrence in the character string STRING of any character
+   in the character string ACCEPT.  Return the number of bytes from the
+   beginning of the string to this occurrence, or to the end of the string
+   if none exists.
+   Unlike strcspn(), this function works correctly in multibyte locales.  */
+_GL_EXTERN_C size_t mbscspn (const char *string, const char *accept)
+     _GL_ATTRIBUTE_PURE
+     _GL_ARG_NONNULL ((1, 2));
+#endif
+
+#if @GNULIB_MBSPBRK@
+/* Find the first occurrence in the character string STRING of any character
+   in the character string ACCEPT.  Return the pointer to it, or NULL if none
+   exists.
+   Unlike strpbrk(), this function works correctly in multibyte locales.  */
+# if defined __hpux
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define mbspbrk rpl_mbspbrk /* avoid collision with HP-UX function */
+#  endif
+_GL_FUNCDECL_RPL (mbspbrk, char *, (const char *string, const char *accept)
+                                   _GL_ATTRIBUTE_PURE
+                                   _GL_ARG_NONNULL ((1, 2)));
+_GL_CXXALIAS_RPL (mbspbrk, char *, (const char *string, const char *accept));
+# else
+_GL_FUNCDECL_SYS (mbspbrk, char *, (const char *string, const char *accept)
+                                   _GL_ATTRIBUTE_PURE
+                                   _GL_ARG_NONNULL ((1, 2)));
+_GL_CXXALIAS_SYS (mbspbrk, char *, (const char *string, const char *accept));
+# endif
+_GL_CXXALIASWARN (mbspbrk);
+#endif
+
+#if @GNULIB_MBSSPN@
+/* Find the first occurrence in the character string STRING of any character
+   not in the character string REJECT.  Return the number of bytes from the
+   beginning of the string to this occurrence, or to the end of the string
+   if none exists.
+   Unlike strspn(), this function works correctly in multibyte locales.  */
+_GL_EXTERN_C size_t mbsspn (const char *string, const char *reject)
+     _GL_ATTRIBUTE_PURE
+     _GL_ARG_NONNULL ((1, 2));
+#endif
+
+#if @GNULIB_MBSSEP@
+/* Search the next delimiter (multibyte character listed in the character
+   string DELIM) starting at the character string *STRINGP.
+   If one is found, overwrite it with a NUL, and advance *STRINGP to point
+   to the next multibyte character after it.  Otherwise, set *STRINGP to NULL.
+   If *STRINGP was already NULL, nothing happens.
+   Return the old value of *STRINGP.
+
+   This is a variant of mbstok_r() that supports empty fields.
+
+   Caveat: It modifies the original string.
+   Caveat: These functions cannot be used on constant strings.
+   Caveat: The identity of the delimiting character is lost.
+
+   See also mbstok_r().  */
+_GL_EXTERN_C char * mbssep (char **stringp, const char *delim)
+     _GL_ARG_NONNULL ((1, 2));
+#endif
+
+#if @GNULIB_MBSTOK_R@
+/* Parse the character string STRING into tokens separated by characters in
+   the character string DELIM.
+   If STRING is NULL, the saved pointer in SAVE_PTR is used as
+   the next starting point.  For example:
+        char s[] = "-abc-=-def";
+        char *sp;
+        x = mbstok_r(s, "-", &sp);      // x = "abc", sp = "=-def"
+        x = mbstok_r(NULL, "-=", &sp);  // x = "def", sp = NULL
+        x = mbstok_r(NULL, "=", &sp);   // x = NULL
+                // s = "abc\0-def\0"
+
+   Caveat: It modifies the original string.
+   Caveat: These functions cannot be used on constant strings.
+   Caveat: The identity of the delimiting character is lost.
+
+   See also mbssep().  */
+_GL_EXTERN_C char * mbstok_r (char *string, const char *delim, char **save_ptr)
+     _GL_ARG_NONNULL ((2, 3));
+#endif
+
+/* Map any int, typically from errno, into an error message.  */
+#if @GNULIB_STRERROR@
+# if @REPLACE_STRERROR@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef strerror
+#   define strerror rpl_strerror
+#  endif
+_GL_FUNCDECL_RPL (strerror, char *, (int));
+_GL_CXXALIAS_RPL (strerror, char *, (int));
+# else
+_GL_CXXALIAS_SYS (strerror, char *, (int));
+# endif
+_GL_CXXALIASWARN (strerror);
+#elif defined GNULIB_POSIXCHECK
+# undef strerror
+/* Assume strerror is always declared.  */
+_GL_WARN_ON_USE (strerror, "strerror is unportable - "
+                 "use gnulib module strerror to guarantee non-NULL result");
+#endif
+
+/* Map any int, typically from errno, into an error message.  Multithread-safe.
+   Uses the POSIX declaration, not the glibc declaration.  */
+#if @GNULIB_STRERROR_R@
+# if @REPLACE_STRERROR_R@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   undef strerror_r
+#   define strerror_r rpl_strerror_r
+#  endif
+_GL_FUNCDECL_RPL (strerror_r, int, (int errnum, char *buf, size_t buflen)
+                                   _GL_ARG_NONNULL ((2)));
+_GL_CXXALIAS_RPL (strerror_r, int, (int errnum, char *buf, size_t buflen));
+# else
+#  if !@HAVE_DECL_STRERROR_R@
+_GL_FUNCDECL_SYS (strerror_r, int, (int errnum, char *buf, size_t buflen)
+                                   _GL_ARG_NONNULL ((2)));
+#  endif
+_GL_CXXALIAS_SYS (strerror_r, int, (int errnum, char *buf, size_t buflen));
+# endif
+# if @HAVE_DECL_STRERROR_R@
+_GL_CXXALIASWARN (strerror_r);
+# endif
+#elif defined GNULIB_POSIXCHECK
+# undef strerror_r
+# if HAVE_RAW_DECL_STRERROR_R
+_GL_WARN_ON_USE (strerror_r, "strerror_r is unportable - "
+                 "use gnulib module strerror_r-posix for portability");
+# endif
+#endif
+
+#if @GNULIB_STRSIGNAL@
+# if @REPLACE_STRSIGNAL@
+#  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
+#   define strsignal rpl_strsignal
+#  endif
+_GL_FUNCDECL_RPL (strsignal, char *, (int __sig));
+_GL_CXXALIAS_RPL (strsignal, char *, (int __sig));
+# else
+#  if ! @HAVE_DECL_STRSIGNAL@
+_GL_FUNCDECL_SYS (strsignal, char *, (int __sig));
+#  endif
+/* Need to cast, because on Cygwin 1.5.x systems, the return type is
+   'const char *'.  */
+_GL_CXXALIAS_SYS_CAST (strsignal, char *, (int __sig));
+# endif
+_GL_CXXALIASWARN (strsignal);
+#elif defined GNULIB_POSIXCHECK
+# undef strsignal
+# if HAVE_RAW_DECL_STRSIGNAL
+_GL_WARN_ON_USE (strsignal, "strsignal is unportable - "
+                 "use gnulib module strsignal for portability");
+# endif
+#endif
+
+#if @GNULIB_STRVERSCMP@
+# if !@HAVE_STRVERSCMP@
+_GL_FUNCDECL_SYS (strverscmp, int, (const char *, const char *)
+                                   _GL_ATTRIBUTE_PURE
+                                   _GL_ARG_NONNULL ((1, 2)));
+# endif
+_GL_CXXALIAS_SYS (strverscmp, int, (const char *, const char *));
+_GL_CXXALIASWARN (strverscmp);
+#elif defined GNULIB_POSIXCHECK
+# undef strverscmp
+# if HAVE_RAW_DECL_STRVERSCMP
+_GL_WARN_ON_USE (strverscmp, "strverscmp is unportable - "
+                 "use gnulib module strverscmp for portability");
+# endif
+#endif
+
+
+#endif /* _@GUARD_PREFIX@_STRING_H */
+#endif /* _@GUARD_PREFIX@_STRING_H */