1# serial 69
2
3# Copyright (C) 1996-2001, 2003-2020 Free Software Foundation, Inc.
4#
5# This file is free software; the Free Software Foundation
6# gives unlimited permission to copy and/or distribute it,
7# with or without modifications, as long as this notice is preserved.
8
9dnl Initially derived from code in GNU grep.
10dnl Mostly written by Jim Meyering.
11
12AC_PREREQ([2.50])
13
14AC_DEFUN([gl_REGEX],
15[
16  AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
17  AC_ARG_WITH([included-regex],
18    [AS_HELP_STRING([--without-included-regex],
19                    [don't compile regex; this is the default on systems
20                     with recent-enough versions of the GNU C Library
21                     (use with caution on other systems).])])
22
23  case $with_included_regex in #(
24  yes|no) ac_use_included_regex=$with_included_regex
25        ;;
26  '')
27    # If the system regex support is good enough that it passes the
28    # following run test, then default to *not* using the included regex.c.
29    # If cross compiling, assume the test would fail and use the included
30    # regex.c.
31    AC_CHECK_DECLS_ONCE([alarm])
32    AC_CHECK_HEADERS_ONCE([malloc.h])
33    AC_CACHE_CHECK([for working re_compile_pattern],
34                   [gl_cv_func_re_compile_pattern_working],
35      [AC_RUN_IFELSE(
36        [AC_LANG_PROGRAM(
37          [[#include <regex.h>
38
39            #include <locale.h>
40            #include <limits.h>
41            #include <string.h>
42
43            #if defined M_CHECK_ACTION || HAVE_DECL_ALARM
44            # include <signal.h>
45            # include <unistd.h>
46            #endif
47
48            #if HAVE_MALLOC_H
49            # include <malloc.h>
50            #endif
51
52            #ifdef M_CHECK_ACTION
53            /* Exit with distinguishable exit code.  */
54            static void sigabrt_no_core (int sig) { raise (SIGTERM); }
55            #endif
56          ]],
57          [[int result = 0;
58            static struct re_pattern_buffer regex;
59            unsigned char folded_chars[UCHAR_MAX + 1];
60            int i;
61            const char *s;
62            struct re_registers regs;
63
64            /* Some builds of glibc go into an infinite loop on this
65               test.  Use alarm to force death, and mallopt to avoid
66               malloc recursion in diagnosing the corrupted heap. */
67#if HAVE_DECL_ALARM
68            signal (SIGALRM, SIG_DFL);
69            alarm (2);
70#endif
71#ifdef M_CHECK_ACTION
72            signal (SIGABRT, sigabrt_no_core);
73            mallopt (M_CHECK_ACTION, 2);
74#endif
75
76            if (setlocale (LC_ALL, "en_US.UTF-8"))
77              {
78                {
79                  /* https://sourceware.org/ml/libc-hacker/2006-09/msg00008.html
80                     This test needs valgrind to catch the bug on Debian
81                     GNU/Linux 3.1 x86, but it might catch the bug better
82                     on other platforms and it shouldn't hurt to try the
83                     test here.  */
84                  static char const pat[] = "insert into";
85                  static char const data[] =
86                    "\xFF\0\x12\xA2\xAA\xC4\xB1,K\x12\xC4\xB1*\xACK";
87                  re_set_syntax (RE_SYNTAX_GREP | RE_HAT_LISTS_NOT_NEWLINE
88                                 | RE_ICASE);
89                  memset (&regex, 0, sizeof regex);
90                  s = re_compile_pattern (pat, sizeof pat - 1, &regex);
91                  if (s)
92                    result |= 1;
93                  else if (re_search (&regex, data, sizeof data - 1,
94                                      0, sizeof data - 1, &regs)
95                           != -1)
96                    result |= 1;
97                  regfree (&regex);
98                }
99
100                {
101                  /* This test is from glibc bug 15078.
102                     The test case is from Andreas Schwab in
103                     <https://sourceware.org/ml/libc-alpha/2013-01/msg00967.html>.
104                     */
105                  static char const pat[] = "[^x]x";
106                  static char const data[] =
107                    /* <U1000><U103B><U103D><U1014><U103A><U102F><U1015><U103A> */
108                    "\xe1\x80\x80"
109                    "\xe1\x80\xbb"
110                    "\xe1\x80\xbd"
111                    "\xe1\x80\x94"
112                    "\xe1\x80\xba"
113                    "\xe1\x80\xaf"
114                    "\xe1\x80\x95"
115                    "\xe1\x80\xba"
116                    "x";
117                  re_set_syntax (0);
118                  memset (&regex, 0, sizeof regex);
119                  s = re_compile_pattern (pat, sizeof pat - 1, &regex);
120                  if (s)
121                    result |= 1;
122                  else
123                    {
124                      i = re_search (&regex, data, sizeof data - 1,
125                                     0, sizeof data - 1, 0);
126                      if (i != 0 && i != 21)
127                        result |= 1;
128                    }
129                  regfree (&regex);
130                }
131
132                if (! setlocale (LC_ALL, "C"))
133                  return 1;
134              }
135
136            /* This test is from glibc bug 3957, reported by Andrew Mackey.  */
137            re_set_syntax (RE_SYNTAX_EGREP | RE_HAT_LISTS_NOT_NEWLINE);
138            memset (&regex, 0, sizeof regex);
139            s = re_compile_pattern ("a[^x]b", 6, &regex);
140            if (s)
141              result |= 2;
142            /* This should fail, but succeeds for glibc-2.5.  */
143            else if (re_search (&regex, "a\nb", 3, 0, 3, &regs) != -1)
144              result |= 2;
145
146            /* This regular expression is from Spencer ere test number 75
147               in grep-2.3.  */
148            re_set_syntax (RE_SYNTAX_POSIX_EGREP);
149            memset (&regex, 0, sizeof regex);
150            for (i = 0; i <= UCHAR_MAX; i++)
151              folded_chars[i] = i;
152            regex.translate = folded_chars;
153            s = re_compile_pattern ("a[[:@:>@:]]b\n", 11, &regex);
154            /* This should fail with _Invalid character class name_ error.  */
155            if (!s)
156              result |= 4;
157
158            /* Ensure that [b-a] is diagnosed as invalid, when
159               using RE_NO_EMPTY_RANGES. */
160            re_set_syntax (RE_SYNTAX_POSIX_EGREP | RE_NO_EMPTY_RANGES);
161            memset (&regex, 0, sizeof regex);
162            s = re_compile_pattern ("a[b-a]", 6, &regex);
163            if (s == 0)
164              result |= 8;
165
166            /* This should succeed, but does not for glibc-2.1.3.  */
167            memset (&regex, 0, sizeof regex);
168            s = re_compile_pattern ("{1", 2, &regex);
169            if (s)
170              result |= 8;
171
172            /* The following example is derived from a problem report
173               against gawk from Jorge Stolfi <stolfi@ic.unicamp.br>.  */
174            memset (&regex, 0, sizeof regex);
175            s = re_compile_pattern ("[an\371]*n", 7, &regex);
176            if (s)
177              result |= 8;
178            /* This should match, but does not for glibc-2.2.1.  */
179            else if (re_match (&regex, "an", 2, 0, &regs) != 2)
180              result |= 8;
181
182            memset (&regex, 0, sizeof regex);
183            s = re_compile_pattern ("x", 1, &regex);
184            if (s)
185              result |= 8;
186            /* glibc-2.2.93 does not work with a negative RANGE argument.  */
187            else if (re_search (&regex, "wxy", 3, 2, -2, &regs) != 1)
188              result |= 8;
189
190            /* The version of regex.c in older versions of gnulib
191               ignored RE_ICASE.  Detect that problem too.  */
192            re_set_syntax (RE_SYNTAX_EMACS | RE_ICASE);
193            memset (&regex, 0, sizeof regex);
194            s = re_compile_pattern ("x", 1, &regex);
195            if (s)
196              result |= 16;
197            else if (re_search (&regex, "WXY", 3, 0, 3, &regs) < 0)
198              result |= 16;
199
200            /* Catch a bug reported by Vin Shelton in
201               https://lists.gnu.org/r/bug-coreutils/2007-06/msg00089.html
202               */
203            re_set_syntax (RE_SYNTAX_POSIX_BASIC
204                           & ~RE_CONTEXT_INVALID_DUP
205                           & ~RE_NO_EMPTY_RANGES);
206            memset (&regex, 0, sizeof regex);
207            s = re_compile_pattern ("[[:alnum:]_-]\\\\+$", 16, &regex);
208            if (s)
209              result |= 32;
210
211            /* REG_STARTEND was added to glibc on 2004-01-15.
212               Reject older versions.  */
213            if (! REG_STARTEND)
214              result |= 64;
215
216            /* Matching with the compiled form of this regexp would provoke
217               an assertion failure prior to glibc-2.28:
218                 regexec.c:1375: pop_fail_stack: Assertion 'num >= 0' failed
219               With glibc-2.28, compilation fails and reports the invalid
220               back reference.  */
221            re_set_syntax (RE_SYNTAX_POSIX_EGREP);
222            memset (&regex, 0, sizeof regex);
223            s = re_compile_pattern ("0|()0|\\1|0", 10, &regex);
224            if (!s || strcmp (s, "Invalid back reference"))
225              result |= 64;
226
227#if 0
228            /* It would be nice to reject hosts whose regoff_t values are too
229               narrow (including glibc on hosts with 64-bit ptrdiff_t and
230               32-bit int), but we should wait until glibc implements this
231               feature.  Otherwise, support for equivalence classes and
232               multibyte collation symbols would always be broken except
233               when compiling --without-included-regex.   */
234            if (sizeof (regoff_t) < sizeof (ptrdiff_t)
235                || sizeof (regoff_t) < sizeof (ssize_t))
236              result |= 64;
237#endif
238
239            return result;
240          ]])],
241        [gl_cv_func_re_compile_pattern_working=yes],
242        [gl_cv_func_re_compile_pattern_working=no],
243        [case "$host_os" in
244                   # Guess no on native Windows.
245           mingw*) gl_cv_func_re_compile_pattern_working="guessing no" ;;
246                   # Otherwise obey --enable-cross-guesses.
247           *)      gl_cv_func_re_compile_pattern_working="$gl_cross_guess_normal" ;;
248         esac
249        ])
250      ])
251    case "$gl_cv_func_re_compile_pattern_working" in #(
252      *yes) ac_use_included_regex=no;; #(
253      *no) ac_use_included_regex=yes;;
254    esac
255    ;;
256  *) AC_MSG_ERROR([Invalid value for --with-included-regex: $with_included_regex])
257    ;;
258  esac
259
260  if test $ac_use_included_regex = yes; then
261    AC_DEFINE([_REGEX_INCLUDE_LIMITS_H], [1],
262      [Define if you want <regex.h> to include <limits.h>, so that it
263       consistently overrides <limits.h>'s RE_DUP_MAX.])
264    AC_DEFINE([_REGEX_LARGE_OFFSETS], [1],
265      [Define if you want regoff_t to be at least as wide POSIX requires.])
266    AC_DEFINE([re_syntax_options], [rpl_re_syntax_options],
267      [Define to rpl_re_syntax_options if the replacement should be used.])
268    AC_DEFINE([re_set_syntax], [rpl_re_set_syntax],
269      [Define to rpl_re_set_syntax if the replacement should be used.])
270    AC_DEFINE([re_compile_pattern], [rpl_re_compile_pattern],
271      [Define to rpl_re_compile_pattern if the replacement should be used.])
272    AC_DEFINE([re_compile_fastmap], [rpl_re_compile_fastmap],
273      [Define to rpl_re_compile_fastmap if the replacement should be used.])
274    AC_DEFINE([re_search], [rpl_re_search],
275      [Define to rpl_re_search if the replacement should be used.])
276    AC_DEFINE([re_search_2], [rpl_re_search_2],
277      [Define to rpl_re_search_2 if the replacement should be used.])
278    AC_DEFINE([re_match], [rpl_re_match],
279      [Define to rpl_re_match if the replacement should be used.])
280    AC_DEFINE([re_match_2], [rpl_re_match_2],
281      [Define to rpl_re_match_2 if the replacement should be used.])
282    AC_DEFINE([re_set_registers], [rpl_re_set_registers],
283      [Define to rpl_re_set_registers if the replacement should be used.])
284    AC_DEFINE([re_comp], [rpl_re_comp],
285      [Define to rpl_re_comp if the replacement should be used.])
286    AC_DEFINE([re_exec], [rpl_re_exec],
287      [Define to rpl_re_exec if the replacement should be used.])
288    AC_DEFINE([regcomp], [rpl_regcomp],
289      [Define to rpl_regcomp if the replacement should be used.])
290    AC_DEFINE([regexec], [rpl_regexec],
291      [Define to rpl_regexec if the replacement should be used.])
292    AC_DEFINE([regerror], [rpl_regerror],
293      [Define to rpl_regerror if the replacement should be used.])
294    AC_DEFINE([regfree], [rpl_regfree],
295      [Define to rpl_regfree if the replacement should be used.])
296  fi
297])
298
299# Prerequisites of lib/regex.c and lib/regex_internal.c.
300AC_DEFUN([gl_PREREQ_REGEX],
301[
302  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
303  AC_REQUIRE([AC_C_INLINE])
304  AC_REQUIRE([AC_C_RESTRICT])
305  AC_REQUIRE([AC_TYPE_MBSTATE_T])
306  AC_REQUIRE([gl_EEMALLOC])
307  AC_REQUIRE([gl_GLIBC21])
308  AC_CHECK_HEADERS([libintl.h])
309  AC_CHECK_FUNCS_ONCE([isblank iswctype])
310  AC_CHECK_DECLS([isblank], [], [], [[#include <ctype.h>]])
311])
312