3 # Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2003, 2004, 2005 Free
4 # Software Foundation, Inc.
6 # This file is free software; the Free Software Foundation
7 # gives unlimited permission to copy and/or distribute it,
8 # with or without modifications, as long as this notice is preserved.
10 dnl Initially derived from code in GNU grep.
11 dnl Mostly written by Jim Meyering.
18 [regcomp.c, regex.c, regex.h,
19 regex_internal.c, regex_internal.h, regexec.c])
21 AC_ARG_WITH([included-regex],
22 [AC_HELP_STRING([--without-included-regex],
23 [don't compile regex; this is the default on
24 systems with recent-enough versions of the GNU C
25 Library (use with caution on other systems)])])
27 case $with_included_regex in
28 yes|no) ac_use_included_regex=$with_included_regex
31 # If the system regex support is good enough that it passes the the
32 # following run test, then default to *not* using the included regex.c.
33 # If cross compiling, assume the test would fail and use the included
34 # regex.c. The first failing regular expression is from `Spencer ere
35 # test #75' in grep-2.3.
36 AC_CACHE_CHECK([for working re_compile_pattern],
37 [gl_cv_func_re_compile_pattern_broken],
42 [[static struct re_pattern_buffer regex;
44 struct re_registers regs;
45 /* Use the POSIX-compliant spelling with leading REG_,
46 rather than the traditional GNU spelling with leading RE_,
47 so that we reject older libc implementations. */
48 re_set_syntax (REG_SYNTAX_POSIX_EGREP);
49 memset (®ex, 0, sizeof (regex));
50 s = re_compile_pattern ("a[:@:>@:]b\n", 9, ®ex);
51 /* This should fail with _Invalid character class name_ error. */
55 /* This should succeed, but does not for e.g. glibc-2.1.3. */
56 memset (®ex, 0, sizeof (regex));
57 s = re_compile_pattern ("{1", 2, ®ex);
62 /* The following example is derived from a problem report
63 against gawk from Jorge Stolfi <stolfi@ic.unicamp.br>. */
64 memset (®ex, 0, sizeof (regex));
65 s = re_compile_pattern ("[an\371]*n", 7, ®ex);
69 /* This should match, but does not for e.g. glibc-2.2.1. */
70 if (re_match (®ex, "an", 2, 0, ®s) != 2)
73 memset (®ex, 0, sizeof (regex));
74 s = re_compile_pattern ("x", 1, ®ex);
78 /* The version of regex.c in e.g. GNU libc-2.2.93 did not
79 work with a negative RANGE argument. */
80 if (re_search (®ex, "wxy", 3, 2, -2, ®s) != 1)
83 /* The version of regex.c in older versions of gnulib
84 ignored REG_IGNORE_CASE (which was then called RE_ICASE).
85 Detect that problem too. */
86 memset (®ex, 0, sizeof (regex));
87 re_set_syntax (REG_SYNTAX_EMACS | REG_IGNORE_CASE);
88 s = re_compile_pattern ("x", 1, ®ex);
92 if (re_search (®ex, "WXY", 3, 0, 3, ®s) < 0)
95 /* REG_STARTEND was added to glibc on 2004-01-15.
96 Reject older versions. */
101 [gl_cv_func_re_compile_pattern_broken=no],
102 [gl_cv_func_re_compile_pattern_broken=yes],
103 dnl When crosscompiling, assume it is broken.
104 [gl_cv_func_re_compile_pattern_broken=yes])])
105 ac_use_included_regex=$gl_cv_func_re_compile_pattern_broken
107 *) AC_MSG_ERROR([Invalid value for --with-included-regex: $with_included_regex])
111 if test $ac_use_included_regex = yes; then
117 # Prerequisites of lib/regex.c and lib/regex_internal.c.
118 AC_DEFUN([gl_PREREQ_REGEX],
120 AC_REQUIRE([AC_GNU_SOURCE])
121 AC_REQUIRE([gl_C_RESTRICT])
122 AC_REQUIRE([AM_LANGINFO_CODESET])
123 AC_CHECK_HEADERS_ONCE([locale.h wchar.h wctype.h])
124 AC_CHECK_FUNCS_ONCE([isblank mbrtowc mempcpy wcrtomb wcscoll])