1# setenv.m4 serial 16
2dnl Copyright (C) 2001-2004, 2006-2010 Free Software Foundation, Inc.
3dnl This file is free software; the Free Software Foundation
4dnl gives unlimited permission to copy and/or distribute it,
5dnl with or without modifications, as long as this notice is preserved.
6
7AC_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])
14
15# Like gl_FUNC_SETENV, except prepare for separate compilation (no AC_LIBOBJ).
16AC_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])
44
45AC_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>
57extern
58#ifdef __cplusplus
59"C"
60#endif
61#if defined(__STDC__) || defined(__cplusplus)
62int unsetenv (const char *name);
63#else
64int unsetenv();
65#endif
66], , gt_cv_func_unsetenv_ret='int', gt_cv_func_unsetenv_ret='void')])
67    if test $gt_cv_func_unsetenv_ret = 'void'; then
68      AC_DEFINE([VOID_UNSETENV], [1], [Define to 1 if unsetenv returns void
69       instead of int.])
70      REPLACE_UNSETENV=1
71      AC_LIBOBJ([unsetenv])
72    fi
73
74    dnl Solaris 10 unsetenv does not remove all copies of a name.
75    AC_CACHE_CHECK([whether unsetenv works on duplicates],
76      [gl_cv_func_unsetenv_works],
77      [AC_RUN_IFELSE([AC_LANG_PROGRAM([[
78       #include <stdlib.h>
79      ]], [[
80       char entry[] = "b=2";
81       if (putenv ((char *) "a=1")) return 1;
82       if (putenv (entry)) return 2;
83       entry[0] = 'a';
84       unsetenv ("a");
85       if (getenv ("a")) return 3;
86      ]])],
87      [gl_cv_func_unsetenv_works=yes], [gl_cv_func_unsetenv_works=no],
88      [gl_cv_func_unsetenv_works="guessing no"])])
89    if test "$gl_cv_func_unsetenv_works" != yes; then
90      REPLACE_UNSETENV=1
91      AC_LIBOBJ([unsetenv])
92    fi
93  fi
94])
95
96# Prerequisites of lib/setenv.c.
97AC_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])
105
106# Prerequisites of lib/unsetenv.c.
107AC_DEFUN([gl_PREREQ_UNSETENV],
108[
109  AC_REQUIRE([gl_ENVIRON])
110  AC_CHECK_HEADERS_ONCE([unistd.h])
111])
112