# setenv.m4 serial 26 dnl Copyright (C) 2001-2004, 2006-2016 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, dnl with or without modifications, as long as this notice is preserved. AC_DEFUN([gl_FUNC_SETENV], [ AC_REQUIRE([gl_FUNC_SETENV_SEPARATE]) AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles if test $ac_cv_func_setenv = no; then HAVE_SETENV=0 else AC_CACHE_CHECK([whether setenv validates arguments], [gl_cv_func_setenv_works], [AC_RUN_IFELSE([AC_LANG_PROGRAM([[ #include <stdlib.h> #include <errno.h> #include <string.h> ]], [[ int result = 0; { if (setenv ("", "", 0) != -1) result |= 1; else if (errno != EINVAL) result |= 2; } { if (setenv ("a", "=", 1) != 0) result |= 4; else if (strcmp (getenv ("a"), "=") != 0) result |= 8; } return result; ]])], [gl_cv_func_setenv_works=yes], [gl_cv_func_setenv_works=no], [case "$host_os" in # Guess yes on glibc systems. *-gnu*) gl_cv_func_setenv_works="guessing yes" ;; # If we don't know, assume the worst. *) gl_cv_func_setenv_works="guessing no" ;; esac ])]) case "$gl_cv_func_setenv_works" in *yes) ;; *) REPLACE_SETENV=1 ;; esac fi ]) # Like gl_FUNC_SETENV, except prepare for separate compilation # (no REPLACE_SETENV, no AC_LIBOBJ). AC_DEFUN([gl_FUNC_SETENV_SEPARATE], [ AC_REQUIRE([gl_STDLIB_H_DEFAULTS]) AC_CHECK_DECLS_ONCE([setenv]) if test $ac_cv_have_decl_setenv = no; then HAVE_DECL_SETENV=0 fi AC_CHECK_FUNCS_ONCE([setenv]) gl_PREREQ_SETENV ]) AC_DEFUN([gl_FUNC_UNSETENV], [ AC_REQUIRE([gl_STDLIB_H_DEFAULTS]) AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles AC_CHECK_DECLS_ONCE([unsetenv]) if test $ac_cv_have_decl_unsetenv = no; then HAVE_DECL_UNSETENV=0 fi AC_CHECK_FUNCS([unsetenv]) if test $ac_cv_func_unsetenv = no; then HAVE_UNSETENV=0 else HAVE_UNSETENV=1 dnl Some BSDs return void, failing to do error checking. AC_CACHE_CHECK([for unsetenv() return type], [gt_cv_func_unsetenv_ret], [AC_COMPILE_IFELSE( [AC_LANG_PROGRAM( [[ #undef _BSD #define _BSD 1 /* unhide unsetenv declaration in OSF/1 5.1 <stdlib.h> */ #include <stdlib.h> extern #ifdef __cplusplus "C" #endif int unsetenv (const char *name); ]], [[]])], [gt_cv_func_unsetenv_ret='int'], [gt_cv_func_unsetenv_ret='void'])]) if test $gt_cv_func_unsetenv_ret = 'void'; then AC_DEFINE([VOID_UNSETENV], [1], [Define to 1 if unsetenv returns void instead of int.]) REPLACE_UNSETENV=1 fi dnl Solaris 10 unsetenv does not remove all copies of a name. dnl Haiku alpha 2 unsetenv gets confused by assignment to environ. dnl OpenBSD 4.7 unsetenv("") does not fail. AC_CACHE_CHECK([whether unsetenv obeys POSIX], [gl_cv_func_unsetenv_works], [AC_RUN_IFELSE([AC_LANG_PROGRAM([[ #include <stdlib.h> #include <errno.h> extern char **environ; ]], [[ char entry1[] = "a=1"; char entry2[] = "b=2"; char *env[] = { entry1, entry2, NULL }; if (putenv ((char *) "a=1")) return 1; if (putenv (entry2)) return 2; entry2[0] = 'a'; unsetenv ("a"); if (getenv ("a")) return 3; if (!unsetenv ("") || errno != EINVAL) return 4; entry2[0] = 'b'; environ = env; if (!getenv ("a")) return 5; entry2[0] = 'a'; unsetenv ("a"); if (getenv ("a")) return 6; ]])], [gl_cv_func_unsetenv_works=yes], [gl_cv_func_unsetenv_works=no], [case "$host_os" in # Guess yes on glibc systems. *-gnu*) gl_cv_func_unsetenv_works="guessing yes" ;; # If we don't know, assume the worst. *) gl_cv_func_unsetenv_works="guessing no" ;; esac ])]) case "$gl_cv_func_unsetenv_works" in *yes) ;; *) REPLACE_UNSETENV=1 ;; esac fi ]) # Prerequisites of lib/setenv.c. AC_DEFUN([gl_PREREQ_SETENV], [ AC_REQUIRE([AC_FUNC_ALLOCA]) AC_REQUIRE([gl_ENVIRON]) AC_CHECK_HEADERS_ONCE([unistd.h]) AC_CHECK_HEADERS([search.h]) AC_CHECK_FUNCS([tsearch]) ]) # Prerequisites of lib/unsetenv.c. AC_DEFUN([gl_PREREQ_UNSETENV], [ AC_REQUIRE([gl_ENVIRON]) AC_CHECK_HEADERS_ONCE([unistd.h]) ])