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-rw-r--r--m4/setenv.m4166
1 files changed, 166 insertions, 0 deletions
diff --git a/m4/setenv.m4 b/m4/setenv.m4
new file mode 100644
index 0000000..2000039
--- /dev/null
+++ b/m4/setenv.m4
@@ -0,0 +1,166 @@
+# setenv.m4 serial 30
+dnl Copyright (C) 2001-2004, 2006-2022 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* | gnu*) gl_cv_func_setenv_works="guessing yes" ;;
+ # Guess yes on musl systems.
+ *-musl*) gl_cv_func_setenv_works="guessing yes" ;;
+ # If we don't know, obey --enable-cross-guesses.
+ *) gl_cv_func_setenv_works="$gl_cross_guess_normal" ;;
+ esac
+ ])])
+ case "$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 $gt_cv_func_unsetenv_ret = 'void'; then
+ AC_DEFINE([VOID_UNSETENV], [1], [Define to 1 if unsetenv returns void
+ instead of int.])
+ REPLACE_UNSETENV=1
+ fi
+
+ dnl Solaris 10 unsetenv does not remove all copies of a name.
+ dnl Haiku alpha 2 unsetenv gets confused by assignment to environ.
+ dnl OpenBSD 4.7 unsetenv("") does not fail.
+ AC_CACHE_CHECK([whether unsetenv obeys POSIX],
+ [gl_cv_func_unsetenv_works],
+ [AC_RUN_IFELSE(
+ [AC_LANG_PROGRAM([[
+ #include <stdlib.h>
+ #include <errno.h>
+ extern char **environ;
+ ]GL_MDA_DEFINES],
+ [[
+ char entry1[] = "a=1";
+ char entry2[] = "b=2";
+ char *env[] = { entry1, entry2, NULL };
+ if (putenv ((char *) "a=1")) return 1;
+ if (putenv (entry2)) return 2;
+ entry2[0] = 'a';
+ unsetenv ("a");
+ if (getenv ("a")) return 3;
+ if (!unsetenv ("") || errno != EINVAL) return 4;
+ entry2[0] = 'b';
+ environ = env;
+ if (!getenv ("a")) return 5;
+ entry2[0] = 'a';
+ unsetenv ("a");
+ if (getenv ("a")) return 6;
+ ]])],
+ [gl_cv_func_unsetenv_works=yes],
+ [gl_cv_func_unsetenv_works=no],
+ [case "$host_os" in
+ # Guess yes on glibc systems.
+ *-gnu*) gl_cv_func_unsetenv_works="guessing yes" ;;
+ # If we don't know, obey --enable-cross-guesses.
+ *) gl_cv_func_unsetenv_works="$gl_cross_guess_normal" ;;
+ esac
+ ])
+ ])
+ case "$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])
+])