diff options
Diffstat (limited to 'gl/m4/setenv.m4')
| -rw-r--r-- | gl/m4/setenv.m4 | 160 |
1 files changed, 160 insertions, 0 deletions
diff --git a/gl/m4/setenv.m4 b/gl/m4/setenv.m4 new file mode 100644 index 0000000..6101274 --- /dev/null +++ b/gl/m4/setenv.m4 @@ -0,0 +1,160 @@ +# setenv.m4 serial 27 +dnl Copyright (C) 2001-2004, 2006-2019 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" ;; + # 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]) +]) |