3 dnl Initially derived from code in GNU grep.
4 dnl Mostly written by Jim Meyering.
6 dnl Usage: jm_INCLUDED_REGEX([lib/regex.c])
8 AC_DEFUN(jm_INCLUDED_REGEX,
10 dnl Even packages that don't use regex.c can use this macro.
11 dnl Of course, for them it doesn't do anything.
13 # Assume we'll default to using the included regex.c.
14 ac_use_included_regex=yes
16 # However, if the system regex support is good enough that it passes the
17 # the following run test, then default to *not* using the included regex.c.
18 # If cross compiling, assume the test would fail and use the included
19 # regex.c. The first failing regular expression is from `Spencer ere
20 # test #75' in grep-2.3.
21 AC_CACHE_CHECK([for working re_compile_pattern],
22 jm_cv_func_working_re_compile_pattern,
29 static struct re_pattern_buffer regex;
31 struct re_registers regs;
32 re_set_syntax (RE_SYNTAX_POSIX_EGREP);
33 /* These two brackets, '[[' and the one in the comment below serve
34 to quote the brackets (unbalanced) in the following line. */
35 s = re_compile_pattern ("a[[:]:]]b\n", 9, ®ex);
36 /* This bracket ']' helps quote the unbalanced expression above. */
37 /* This should fail with _Invalid character class name_ error. */
41 /* This should succeed, but doesn't for e.g. glibc-2.1.3. */
42 s = re_compile_pattern ("{1", 2, ®ex);
47 /* The following example is derived from a problem report
48 against gawk from Jorge Stolfi <stolfi@ic.unicamp.br>. */
49 s = re_compile_pattern ("[[anĂ¹]]*n", 7, ®ex);
53 /* This should match, but doesn't for e.g. glibc-2.2.1. */
54 if (re_match (®ex, "an", 2, 0, ®s) != 2)
60 jm_cv_func_working_re_compile_pattern=yes,
61 jm_cv_func_working_re_compile_pattern=no,
62 dnl When crosscompiling, assume it's broken.
63 jm_cv_func_working_re_compile_pattern=no))
64 if test $jm_cv_func_working_re_compile_pattern = yes; then
65 ac_use_included_regex=no
68 test -n "$1" || AC_MSG_ERROR([missing argument])
69 m4_syscmd([test -f $1])
72 AC_ARG_WITH(included-regex,
73 [ --without-included-regex don't compile regex; this is the default on
74 systems with version 2 of the GNU C library
75 (use with caution on other system)],
76 jm_with_regex=$withval,
77 jm_with_regex=$ac_use_included_regex)
78 if test "$jm_with_regex" = yes; then