1# setenv.m4 serial 24 2dnl Copyright (C) 2001-2004, 2006-2011 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 $ac_cv_func_setenv = no; then 11 HAVE_SETENV=0 12 else 13 AC_CACHE_CHECK([whether setenv validates arguments], 14 [gl_cv_func_setenv_works], 15 [AC_RUN_IFELSE([AC_LANG_PROGRAM([[ 16 #include <stdlib.h> 17 #include <errno.h> 18 #include <string.h> 19 ]], [[ 20 int result = 0; 21 { 22 if (setenv ("", "", 0) != -1) 23 result |= 1; 24 else if (errno != EINVAL) 25 result |= 2; 26 } 27 { 28 if (setenv ("a", "=", 1) != 0) 29 result |= 4; 30 else if (strcmp (getenv ("a"), "=") != 0) 31 result |= 8; 32 } 33 return result; 34 ]])], 35 [gl_cv_func_setenv_works=yes], [gl_cv_func_setenv_works=no], 36 [gl_cv_func_setenv_works="guessing no"])]) 37 if test "$gl_cv_func_setenv_works" != yes; then 38 REPLACE_SETENV=1 39 fi 40 fi 41]) 42 43# Like gl_FUNC_SETENV, except prepare for separate compilation 44# (no REPLACE_SETENV, no AC_LIBOBJ). 45AC_DEFUN([gl_FUNC_SETENV_SEPARATE], 46[ 47 AC_REQUIRE([gl_STDLIB_H_DEFAULTS]) 48 AC_CHECK_DECLS_ONCE([setenv]) 49 if test $ac_cv_have_decl_setenv = no; then 50 HAVE_DECL_SETENV=0 51 fi 52 AC_CHECK_FUNCS_ONCE([setenv]) 53 gl_PREREQ_SETENV 54]) 55 56AC_DEFUN([gl_FUNC_UNSETENV], 57[ 58 AC_REQUIRE([gl_STDLIB_H_DEFAULTS]) 59 AC_CHECK_DECLS_ONCE([unsetenv]) 60 if test $ac_cv_have_decl_unsetenv = no; then 61 HAVE_DECL_UNSETENV=0 62 fi 63 AC_CHECK_FUNCS([unsetenv]) 64 if test $ac_cv_func_unsetenv = no; then 65 HAVE_UNSETENV=0 66 else 67 HAVE_UNSETENV=1 68 dnl Some BSDs return void, failing to do error checking. 69 AC_CACHE_CHECK([for unsetenv() return type], [gt_cv_func_unsetenv_ret], 70 [AC_COMPILE_IFELSE( 71 [AC_LANG_PROGRAM( 72 [[ 73#undef _BSD 74#define _BSD 1 /* unhide unsetenv declaration in OSF/1 5.1 <stdlib.h> */ 75#include <stdlib.h> 76extern 77#ifdef __cplusplus 78"C" 79#endif 80#if defined(__STDC__) || defined(__cplusplus) 81int unsetenv (const char *name); 82#else 83int unsetenv(); 84#endif 85 ]], 86 [[]])], 87 [gt_cv_func_unsetenv_ret='int'], 88 [gt_cv_func_unsetenv_ret='void'])]) 89 if test $gt_cv_func_unsetenv_ret = 'void'; then 90 AC_DEFINE([VOID_UNSETENV], [1], [Define to 1 if unsetenv returns void 91 instead of int.]) 92 REPLACE_UNSETENV=1 93 fi 94 95 dnl Solaris 10 unsetenv does not remove all copies of a name. 96 dnl Haiku alpha 2 unsetenv gets confused by assignment to environ. 97 dnl OpenBSD 4.7 unsetenv("") does not fail. 98 AC_CACHE_CHECK([whether unsetenv obeys POSIX], 99 [gl_cv_func_unsetenv_works], 100 [AC_RUN_IFELSE([AC_LANG_PROGRAM([[ 101 #include <stdlib.h> 102 #include <errno.h> 103 extern char **environ; 104 ]], [[ 105 char entry1[] = "a=1"; 106 char entry2[] = "b=2"; 107 char *env[] = { entry1, entry2, NULL }; 108 if (putenv ((char *) "a=1")) return 1; 109 if (putenv (entry2)) return 2; 110 entry2[0] = 'a'; 111 unsetenv ("a"); 112 if (getenv ("a")) return 3; 113 if (!unsetenv ("") || errno != EINVAL) return 4; 114 entry2[0] = 'b'; 115 environ = env; 116 if (!getenv ("a")) return 5; 117 entry2[0] = 'a'; 118 unsetenv ("a"); 119 if (getenv ("a")) return 6; 120 ]])], 121 [gl_cv_func_unsetenv_works=yes], [gl_cv_func_unsetenv_works=no], 122 [gl_cv_func_unsetenv_works="guessing no"])]) 123 if test "$gl_cv_func_unsetenv_works" != yes; then 124 REPLACE_UNSETENV=1 125 fi 126 fi 127]) 128 129# Prerequisites of lib/setenv.c. 130AC_DEFUN([gl_PREREQ_SETENV], 131[ 132 AC_REQUIRE([AC_FUNC_ALLOCA]) 133 AC_REQUIRE([gl_ENVIRON]) 134 AC_CHECK_HEADERS_ONCE([unistd.h]) 135 AC_CHECK_HEADERS([search.h]) 136 AC_CHECK_FUNCS([tsearch]) 137]) 138 139# Prerequisites of lib/unsetenv.c. 140AC_DEFUN([gl_PREREQ_UNSETENV], 141[ 142 AC_REQUIRE([gl_ENVIRON]) 143 AC_CHECK_HEADERS_ONCE([unistd.h]) 144]) 145