X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Fsys_select_h.m4;h=0bb097e1a7395af4f103fe94ce7b5de947705076;hb=0963898828c9a6b76a2cf959f34b4e758fc4e265;hp=f7070fad898901612ec2e43a19e70e7c065f3e2c;hpb=7e5eb8ffca4761e3074bf800612e095a6e7d9a6f;p=gnulib.git

diff --git a/m4/sys_select_h.m4 b/m4/sys_select_h.m4
index f7070fad8..0bb097e1a 100644
--- a/m4/sys_select_h.m4
+++ b/m4/sys_select_h.m4
@@ -1,18 +1,76 @@
-# sys_select_h.m4 serial 1
-dnl Copyright (C) 2006 Free Software Foundation, Inc.
+# sys_select_h.m4 serial 8
+dnl Copyright (C) 2006-2009 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.
 
-dnl Adapted from arpa_inet.m4, written by Simon Josefsson.
-
 AC_DEFUN([gl_HEADER_SYS_SELECT],
 [
-  AC_CHECK_HEADERS_ONCE([sys/select.h])
-  if test $ac_cv_header_sys_select_h = yes; then
+  AC_REQUIRE([gl_HEADER_SYS_SOCKET])
+  AC_REQUIRE([gl_SYS_SELECT_H_DEFAULTS])
+  AC_CACHE_CHECK([whether <sys/select.h> is self-contained],
+    [gl_cv_header_sys_select_h_selfcontained],
+    [
+      dnl Test against two bugs:
+      dnl 1. On many platforms, <sys/select.h> assumes prior inclusion of
+      dnl    <sys/types.h>.
+      dnl 2. On OSF/1 4.0, <sys/select.h> provides only a forward declaration
+      dnl    of 'struct timeval', and no definition of this type.
+      AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <sys/select.h>]],
+					 [[struct timeval b;]])],
+        [gl_cv_header_sys_select_h_selfcontained=yes],
+        [gl_cv_header_sys_select_h_selfcontained=no])
+      dnl Test against another bug:
+      dnl 3. On Solaris 10, <sys/select.h> provides an FD_ZERO implementation
+      dnl    that relies on memset(), but without including <string.h>.
+      if test $gl_cv_header_sys_select_h_selfcontained = yes; then
+        AC_COMPILE_IFELSE(
+          [AC_LANG_PROGRAM([[#include <sys/select.h>]],
+                           [[int memset; int bzero;]])
+          ],
+          [AC_LINK_IFELSE(
+             [AC_LANG_PROGRAM([[#include <sys/select.h>]], [[
+                  #undef memset
+                  #define memset nonexistent_memset
+                  extern void *memset (void *, int, unsigned long);
+                  #undef bzero
+                  #define bzero nonexistent_bzero
+                  extern void bzero (void *, unsigned long);
+                  fd_set fds;
+                  FD_ZERO (&fds);
+                ]])
+             ],
+             [],
+             [gl_cv_header_sys_select_h_selfcontained=no])
+          ])
+      fi
+    ])
+  if test $gl_cv_header_sys_select_h_selfcontained = yes; then
     SYS_SELECT_H=''
   else
     SYS_SELECT_H='sys/select.h'
+    gl_CHECK_NEXT_HEADERS([sys/select.h])
+    if test $ac_cv_header_sys_select_h = yes; then
+      HAVE_SYS_SELECT_H=1
+    else
+      HAVE_SYS_SELECT_H=0
+    fi
+    AC_SUBST([HAVE_SYS_SELECT_H])
+    gl_PREREQ_SYS_H_WINSOCK2
   fi
-  AC_SUBST(SYS_SELECT_H)
+  AC_SUBST([SYS_SELECT_H])
+])
+
+AC_DEFUN([gl_SYS_SELECT_MODULE_INDICATOR],
+[
+  dnl Use AC_REQUIRE here, so that the default settings are expanded once only.
+  AC_REQUIRE([gl_SYS_SELECT_H_DEFAULTS])
+  GNULIB_[]m4_translit([$1],[abcdefghijklmnopqrstuvwxyz./-],[ABCDEFGHIJKLMNOPQRSTUVWXYZ___])=1
+])
+
+AC_DEFUN([gl_SYS_SELECT_H_DEFAULTS],
+[
+  GNULIB_SELECT=0; AC_SUBST([GNULIB_SELECT])
+  dnl Assume proper GNU behavior unless another module says otherwise.
+  REPLACE_SELECT=0; AC_SUBST([REPLACE_SELECT])
 ])