xref: /netbsd-src/external/gpl2/xcvs/dist/m4/regex.m4 (revision a7c918477dd5f12c1da816ba05caf44eab2d06d6) 
1#serial 29
2
3# Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2003, 2004, 2005 Free
4# Software Foundation, Inc.
5#
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.
9
10dnl Initially derived from code in GNU grep.
11dnl Mostly written by Jim Meyering.
12
13AC_PREREQ([2.50])
14
15AC_DEFUN([gl_REGEX],
16[
17  AC_REQUIRE([AC_SYS_LARGEFILE]) dnl for a sufficently-wide off_t
18  AC_DEFINE([_REGEX_LARGE_OFFSETS], 1,
19    [Define if you want regoff_t to be at least as wide POSIX requires.])
20
21  AC_LIBSOURCES(
22    [regcomp.c, regex.c, regex.h,
23     regex_internal.c, regex_internal.h, regexec.c])
24
25  AC_ARG_WITH([included-regex],
26    [AC_HELP_STRING([--without-included-regex],
27		    [don't compile regex; this is the default on
28		     systems with recent-enough versions of the GNU C
29		     Library (use with caution on other systems)])])
30
31  case $with_included_regex in
32  yes|no) ac_use_included_regex=$with_included_regex
33	;;
34  '')
35    # If the system regex support is good enough that it passes the the
36    # following run test, then default to *not* using the included regex.c.
37    # If cross compiling, assume the test would fail and use the included
38    # regex.c.  The first failing regular expression is from `Spencer ere
39    # test #75' in grep-2.3.
40    AC_CACHE_CHECK([for working re_compile_pattern],
41		   [gl_cv_func_re_compile_pattern_broken],
42      [AC_RUN_IFELSE(
43	[AC_LANG_PROGRAM(
44	  [AC_INCLUDES_DEFAULT
45	   #include <regex.h>],
46	  [[static struct re_pattern_buffer regex;
47	    const char *s;
48	    struct re_registers regs;
49	    /* Use the POSIX-compliant spelling with leading REG_,
50	       rather than the traditional GNU spelling with leading RE_,
51	       so that we reject older libc implementations.  */
52	    re_set_syntax (REG_SYNTAX_POSIX_EGREP);
53	    memset (&regex, 0, sizeof (regex));
54	    s = re_compile_pattern ("a[:@:>@:]b\n", 9, &regex);
55	    /* This should fail with _Invalid character class name_ error.  */
56	    if (!s)
57	      exit (1);
58
59	    /* This should succeed, but does not for e.g. glibc-2.1.3.  */
60	    memset (&regex, 0, sizeof (regex));
61	    s = re_compile_pattern ("{1", 2, &regex);
62
63	    if (s)
64	      exit (1);
65
66	    /* The following example is derived from a problem report
67	       against gawk from Jorge Stolfi <stolfi@ic.unicamp.br>.  */
68	    memset (&regex, 0, sizeof (regex));
69	    s = re_compile_pattern ("[an\371]*n", 7, &regex);
70	    if (s)
71	      exit (1);
72
73	    /* This should match, but does not for e.g. glibc-2.2.1.  */
74	    if (re_match (&regex, "an", 2, 0, &regs) != 2)
75	      exit (1);
76
77	    memset (&regex, 0, sizeof (regex));
78	    s = re_compile_pattern ("x", 1, &regex);
79	    if (s)
80	      exit (1);
81
82	    /* The version of regex.c in e.g. GNU libc-2.2.93 did not
83	       work with a negative RANGE argument.  */
84	    if (re_search (&regex, "wxy", 3, 2, -2, &regs) != 1)
85	      exit (1);
86
87	    /* The version of regex.c in older versions of gnulib
88	       ignored REG_IGNORE_CASE (which was then called RE_ICASE).
89	       Detect that problem too.  */
90	    memset (&regex, 0, sizeof (regex));
91	    re_set_syntax (REG_SYNTAX_EMACS | REG_IGNORE_CASE);
92	    s = re_compile_pattern ("x", 1, &regex);
93	    if (s)
94	      exit (1);
95
96	    if (re_search (&regex, "WXY", 3, 0, 3, &regs) < 0)
97	      exit (1);
98
99	    /* REG_STARTEND was added to glibc on 2004-01-15.
100	       Reject older versions.  */
101	    if (! REG_STARTEND)
102	      exit (1);
103
104	    /* Reject hosts whose regoff_t values are too narrow.
105	       These include glibc 2.3.5 on hosts with 64-bit off_t
106	       and 32-bit int, and Solaris 10 on hosts with 32-bit int
107	       and _FILE_OFFSET_BITS=64.  */
108	    if (sizeof (regoff_t) < sizeof (off_t))
109	      exit (1);
110
111	    exit (0);]])],
112       [gl_cv_func_re_compile_pattern_broken=no],
113       [gl_cv_func_re_compile_pattern_broken=yes],
114       dnl When crosscompiling, assume it is broken.
115       [gl_cv_func_re_compile_pattern_broken=yes])])
116    ac_use_included_regex=$gl_cv_func_re_compile_pattern_broken
117    ;;
118  *) AC_MSG_ERROR([Invalid value for --with-included-regex: $with_included_regex])
119    ;;
120  esac
121
122  if test $ac_use_included_regex = yes; then
123    AC_LIBOBJ([regex])
124    gl_PREREQ_REGEX
125  fi
126])
127
128# Prerequisites of lib/regex.c and lib/regex_internal.c.
129AC_DEFUN([gl_PREREQ_REGEX],
130[
131  AC_REQUIRE([AC_GNU_SOURCE])
132  AC_REQUIRE([gl_C_RESTRICT])
133  AC_REQUIRE([AM_LANGINFO_CODESET])
134  AC_CHECK_HEADERS_ONCE([locale.h wchar.h wctype.h])
135  AC_CHECK_FUNCS_ONCE([isblank mbrtowc mempcpy wcrtomb wcscoll])
136])
137