1 # setenv.m4 serial 16
2 dnl Copyright (C) 2001-2004, 2006-2010 Free Software Foundation, Inc.
3 dnl This file is free software; the Free Software Foundation
4 dnl gives unlimited permission to copy and/or distribute it,
5 dnl with or without modifications, as long as this notice is preserved.
7 AC_DEFUN([gl_FUNC_SETENV],
8 [
9 AC_REQUIRE([gl_FUNC_SETENV_SEPARATE])
10 if test $HAVE_SETENV$REPLACE_SETENV != 10; then
11 AC_LIBOBJ([setenv])
12 fi
13 ])
15 # Like gl_FUNC_SETENV, except prepare for separate compilation (no AC_LIBOBJ).
16 AC_DEFUN([gl_FUNC_SETENV_SEPARATE],
17 [
18 AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
19 AC_CHECK_FUNCS_ONCE([setenv])
20 if test $ac_cv_func_setenv = no; then
21 HAVE_SETENV=0
22 else
23 AC_CACHE_CHECK([whether setenv validates arguments],
24 [gl_cv_func_setenv_works],
25 [AC_RUN_IFELSE([AC_LANG_PROGRAM([[
26 #include <stdlib.h>
27 #include <errno.h>
28 #include <string.h>
29 ]], [[
30 if (setenv ("", "", 0) != -1) return 1;
31 if (errno != EINVAL) return 2;
32 if (setenv ("a", "=", 1) != 0) return 3;
33 if (strcmp (getenv ("a"), "=") != 0) return 4;
34 ]])],
35 [gl_cv_func_setenv_works=yes], [gl_cv_func_setenv_works=no],
36 [gl_cv_func_setenv_works="guessing no"])])
37 if test "$gl_cv_func_setenv_works" != yes; then
38 REPLACE_SETENV=1
39 AC_LIBOBJ([setenv])
40 fi
41 fi
42 gl_PREREQ_SETENV
43 ])
45 AC_DEFUN([gl_FUNC_UNSETENV],
46 [
47 AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
48 AC_CHECK_FUNCS([unsetenv])
49 if test $ac_cv_func_unsetenv = no; then
50 HAVE_UNSETENV=0
51 AC_LIBOBJ([unsetenv])
52 gl_PREREQ_UNSETENV
53 else
54 dnl Some BSDs return void, failing to do error checking.
55 AC_CACHE_CHECK([for unsetenv() return type], [gt_cv_func_unsetenv_ret],
56 [AC_TRY_COMPILE([#include <stdlib.h>
57 extern
58 #ifdef __cplusplus
59 "C"
60 #endif
61 #if defined(__STDC__) || defined(__cplusplus)
62 int unsetenv (const char *name);
63 #else
64 int unsetenv();
65 #endif
66 ], , gt_cv_func_unsetenv_ret='int', gt_cv_func_unsetenv_ret='void')])
67 if test $gt_cv_func_unsetenv_ret = 'void'; then
68 AC_DEFINE([VOID_UNSETENV], [1], [Define to 1 if unsetenv returns void
69 instead of int.])
70 REPLACE_UNSETENV=1
71 AC_LIBOBJ([unsetenv])
72 fi
74 dnl Solaris 10 unsetenv does not remove all copies of a name.
75 AC_CACHE_CHECK([whether unsetenv works on duplicates],
76 [gl_cv_func_unsetenv_works],
77 [AC_RUN_IFELSE([AC_LANG_PROGRAM([[
78 #include <stdlib.h>
79 ]], [[
80 char entry[] = "b=2";
81 if (putenv ((char *) "a=1")) return 1;
82 if (putenv (entry)) return 2;
83 entry[0] = 'a';
84 unsetenv ("a");
85 if (getenv ("a")) return 3;
86 ]])],
87 [gl_cv_func_unsetenv_works=yes], [gl_cv_func_unsetenv_works=no],
88 [gl_cv_func_unsetenv_works="guessing no"])])
89 if test "$gl_cv_func_unsetenv_works" != yes; then
90 REPLACE_UNSETENV=1
91 AC_LIBOBJ([unsetenv])
92 fi
93 fi
94 ])
96 # Prerequisites of lib/setenv.c.
97 AC_DEFUN([gl_PREREQ_SETENV],
98 [
99 AC_REQUIRE([AC_FUNC_ALLOCA])
100 AC_REQUIRE([gl_ENVIRON])
101 AC_CHECK_HEADERS_ONCE([unistd.h])
102 AC_CHECK_HEADERS([search.h])
103 AC_CHECK_FUNCS([tsearch])
104 ])
106 # Prerequisites of lib/unsetenv.c.
107 AC_DEFUN([gl_PREREQ_UNSETENV],
108 [
109 AC_REQUIRE([gl_ENVIRON])
110 AC_CHECK_HEADERS_ONCE([unistd.h])
111 ])