2 dnl Copyright (C) 2001-2004, 2006-2014 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],
9 AC_REQUIRE([gl_FUNC_SETENV_SEPARATE])
10 AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
11 if test $ac_cv_func_setenv = no; then
14 AC_CACHE_CHECK([whether setenv validates arguments],
15 [gl_cv_func_setenv_works],
16 [AC_RUN_IFELSE([AC_LANG_PROGRAM([[
23 if (setenv ("", "", 0) != -1)
25 else if (errno != EINVAL)
29 if (setenv ("a", "=", 1) != 0)
31 else if (strcmp (getenv ("a"), "=") != 0)
36 [gl_cv_func_setenv_works=yes], [gl_cv_func_setenv_works=no],
38 # Guess yes on glibc systems.
39 *-gnu*) gl_cv_func_setenv_works="guessing yes" ;;
40 # If we don't know, assume the worst.
41 *) gl_cv_func_setenv_works="guessing no" ;;
44 case "$gl_cv_func_setenv_works" in
53 # Like gl_FUNC_SETENV, except prepare for separate compilation
54 # (no REPLACE_SETENV, no AC_LIBOBJ).
55 AC_DEFUN([gl_FUNC_SETENV_SEPARATE],
57 AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
58 AC_CHECK_DECLS_ONCE([setenv])
59 if test $ac_cv_have_decl_setenv = no; then
62 AC_CHECK_FUNCS_ONCE([setenv])
66 AC_DEFUN([gl_FUNC_UNSETENV],
68 AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
69 AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
70 AC_CHECK_DECLS_ONCE([unsetenv])
71 if test $ac_cv_have_decl_unsetenv = no; then
74 AC_CHECK_FUNCS([unsetenv])
75 if test $ac_cv_func_unsetenv = no; then
79 dnl Some BSDs return void, failing to do error checking.
80 AC_CACHE_CHECK([for unsetenv() return type], [gt_cv_func_unsetenv_ret],
85 #define _BSD 1 /* unhide unsetenv declaration in OSF/1 5.1 <stdlib.h> */
91 int unsetenv (const char *name);
94 [gt_cv_func_unsetenv_ret='int'],
95 [gt_cv_func_unsetenv_ret='void'])])
96 if test $gt_cv_func_unsetenv_ret = 'void'; then
97 AC_DEFINE([VOID_UNSETENV], [1], [Define to 1 if unsetenv returns void
102 dnl Solaris 10 unsetenv does not remove all copies of a name.
103 dnl Haiku alpha 2 unsetenv gets confused by assignment to environ.
104 dnl OpenBSD 4.7 unsetenv("") does not fail.
105 AC_CACHE_CHECK([whether unsetenv obeys POSIX],
106 [gl_cv_func_unsetenv_works],
107 [AC_RUN_IFELSE([AC_LANG_PROGRAM([[
110 extern char **environ;
112 char entry1[] = "a=1";
113 char entry2[] = "b=2";
114 char *env[] = { entry1, entry2, NULL };
115 if (putenv ((char *) "a=1")) return 1;
116 if (putenv (entry2)) return 2;
119 if (getenv ("a")) return 3;
120 if (!unsetenv ("") || errno != EINVAL) return 4;
123 if (!getenv ("a")) return 5;
126 if (getenv ("a")) return 6;
128 [gl_cv_func_unsetenv_works=yes], [gl_cv_func_unsetenv_works=no],
130 # Guess yes on glibc systems.
131 *-gnu*) gl_cv_func_unsetenv_works="guessing yes" ;;
132 # If we don't know, assume the worst.
133 *) gl_cv_func_unsetenv_works="guessing no" ;;
136 case "$gl_cv_func_unsetenv_works" in
145 # Prerequisites of lib/setenv.c.
146 AC_DEFUN([gl_PREREQ_SETENV],
148 AC_REQUIRE([AC_FUNC_ALLOCA])
149 AC_REQUIRE([gl_ENVIRON])
150 AC_CHECK_HEADERS_ONCE([unistd.h])
151 AC_CHECK_HEADERS([search.h])
152 AC_CHECK_FUNCS([tsearch])
155 # Prerequisites of lib/unsetenv.c.
156 AC_DEFUN([gl_PREREQ_UNSETENV],
158 AC_REQUIRE([gl_ENVIRON])
159 AC_CHECK_HEADERS_ONCE([unistd.h])