strdup: Improve idiom.

[gnulib.git] / m4 / sockets.m4

diff --git a/m4/sockets.m4 b/m4/sockets.m4
index 615b6e8..aefb936 100644 (file)
--- a/m4/sockets.m4
+++ b/m4/sockets.m4
@@ -1,31 +1,86 @@
-# sockets.m4 serial 1
-dnl Copyright (C) 2008 Free Software Foundation, Inc.
+# sockets.m4 serial 6
+dnl Copyright (C) 2008, 2009, 2010 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_SOCKETS],
 [
-  AC_REQUIRE([gl_HEADER_SYS_SOCKET])dnl for HAVE_SYS_SOCKET_H, HAVE_WINSOCK2_H
+  AC_REQUIRE([AC_C_INLINE])
 
-  AC_CACHE_CHECK([if we need to call WSAStartup in winsock2.h and -lws2_32],
-                 [gl_cv_func_wsastartup], [
-    am_save_LIBS="$LIBS"
-    LIBS="$LIBS -lws2_32"
-    AC_TRY_LINK([
+  gl_PREREQ_SYS_H_WINSOCK2 dnl for HAVE_WINSOCK2_H
+  LIBSOCKET=
+  if test $HAVE_WINSOCK2_H = 1; then
+    dnl Native Windows API (not Cygwin).
+    AC_CACHE_CHECK([if we need to call WSAStartup in winsock2.h and -lws2_32],
+                   [gl_cv_func_wsastartup], [
+      gl_save_LIBS="$LIBS"
+      LIBS="$LIBS -lws2_32"
+      AC_LINK_IFELSE([AC_LANG_PROGRAM([[
 #ifdef HAVE_WINSOCK2_H
 # include <winsock2.h>
-#endif], [
-      WORD wVersionRequested = MAKEWORD(1, 1);
-      WSADATA wsaData;
-      int err = WSAStartup(wVersionRequested, &wsaData);
-      WSACleanup ();],
-      gl_cv_func_wsastartup=yes, gl_cv_func_wsastartup=no)
-    LIBS="$am_save_LIBS"])
-  if test "$gl_cv_func_wsastartup" = "yes"; then
-    AC_DEFINE([WINDOWS_SOCKETS], 1, [Define if WSAStartup is needed.])
-    LIBS="$LIBS -lws2_32"
+#endif]], [[
+          WORD wVersionRequested = MAKEWORD(1, 1);
+          WSADATA wsaData;
+          int err = WSAStartup(wVersionRequested, &wsaData);
+          WSACleanup ();]])],
+        gl_cv_func_wsastartup=yes, gl_cv_func_wsastartup=no)
+      LIBS="$gl_save_LIBS"
+    ])
+    if test "$gl_cv_func_wsastartup" = "yes"; then
+      AC_DEFINE([WINDOWS_SOCKETS], [1], [Define if WSAStartup is needed.])
+      LIBSOCKET='-lws2_32'
+    fi
+  else
+    dnl Unix API.
+    dnl Solaris has most socket functions in libsocket.
+    dnl Haiku has most socket functions in libnetwork.
+    dnl BeOS has most socket functions in libnet.
+    AC_CACHE_CHECK([for library containing setsockopt], [gl_cv_lib_socket], [
+      gl_cv_lib_socket=
+      AC_LINK_IFELSE([AC_LANG_PROGRAM([[extern
+#ifdef __cplusplus
+"C"
+#endif
+char setsockopt();]], [[setsockopt();]])],
+        [],
+        [gl_save_LIBS="$LIBS"
+         LIBS="$gl_save_LIBS -lsocket"
+         AC_LINK_IFELSE([AC_LANG_PROGRAM([[extern
+#ifdef __cplusplus
+"C"
+#endif
+char setsockopt();]], [[setsockopt();]])],
+           [gl_cv_lib_socket="-lsocket"])
+         if test -z "$gl_cv_lib_socket"; then
+           LIBS="$gl_save_LIBS -lnetwork"
+           AC_LINK_IFELSE([AC_LANG_PROGRAM([[extern
+#ifdef __cplusplus
+"C"
+#endif
+char setsockopt();]], [[setsockopt();]])],
+             [gl_cv_lib_socket="-lnetwork"])
+           if test -z "$gl_cv_lib_socket"; then
+             LIBS="$gl_save_LIBS -lnet"
+             AC_LINK_IFELSE([AC_LANG_PROGRAM([[extern
+#ifdef __cplusplus
+"C"
+#endif
+char setsockopt();]], [[setsockopt();]])],
+               [gl_cv_lib_socket="-lnet"])
+           fi
+         fi
+         LIBS="$gl_save_LIBS"
+        ])
+      if test -z "$gl_cv_lib_socket"; then
+        gl_cv_lib_socket="none needed"
+      fi
+    ])
+    if test "$gl_cv_lib_socket" != "none needed"; then
+      LIBSOCKET="$gl_cv_lib_socket"
+    fi
   fi
+  AC_SUBST([LIBSOCKET])
   gl_PREREQ_SOCKETS
 ])