Enhance configure socklen_t (#640)

Patch by: michaelortmann

Replace handcrafted code with GNU Autoconf Archive Macro.

aclocal.m4

@@ -23,6 +23,7 @@ builtin(include,m4/tcl.m4)
 dnl Load gnu autoconf archive macros
 builtin(include,m4/ax_create_stdint_h.m4)
 builtin(include,m4/ax_lib_socket_nsl.m4)
+builtin(include,m4/ax_type_socklen_t.m4)
 
 
 dnl
@@ -283,40 +284,6 @@ dnl Checks for types and functions.
 dnl
 
 
-dnl EGG_CHECK_SOCKLEN_T()
-dnl
-dnl Check for the socklen_t type.
-dnl
-AC_DEFUN([EGG_CHECK_SOCKLEN_T],
-[
-  AC_CACHE_CHECK([for socklen_t], egg_cv_socklen_t, [
-    AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
-      #include <unistd.h>
-      #include <sys/param.h>
-      #include <sys/types.h>
-      #include <sys/socket.h>
-      #include <netinet/in.h>
-      #include <arpa/inet.h>
-    ]],[[
-        socklen_t test = 55;
-
-        if (test != 55)
-          return(1);
-
-        return(0);
-    ]])], [
-      egg_cv_socklen_t="yes"
-    ], [
-      egg_cv_socklen_t="no"
-    ])
-  ])
-
-  if test "$egg_cv_socklen_t" = yes; then
-    AC_DEFINE(HAVE_SOCKLEN_T, 1, [Define to 1 if you have the `socklen_t' type.])
-  fi
-])
-
-
 dnl EGG_FUNC_VPRINTF()
 dnl
 AC_DEFUN([EGG_FUNC_VPRINTF],

configure.ac

@@ -103,7 +103,7 @@ AC_TYPE_PID_T
 AC_TYPE_SIZE_T
 AC_STRUCT_TIMEZONE
 AC_C_VOLATILE
-EGG_CHECK_SOCKLEN_T
+AX_TYPE_SOCKLEN_T
 
 
 # Create stdint.h C99 compatibility header.

m4/ax_type_socklen_t.m4

@@ -0,0 +1,59 @@
+# ===========================================================================
+#    https://www.gnu.org/software/autoconf-archive/ax_type_socklen_t.html
+# ===========================================================================
+#
+# SYNOPSIS
+#
+#   AX_TYPE_SOCKLEN_T
+#
+# DESCRIPTION
+#
+#   Check whether sys/socket.h defines type socklen_t. Please note that some
+#   systems require sys/types.h to be included before sys/socket.h can be
+#   compiled.
+#
+# LICENSE
+#
+#   Copyright (c) 2008 Lars Brinkhoff <lars@nocrew.org>
+#
+#   This program is free software; you can redistribute it and/or modify it
+#   under the terms of the GNU General Public License as published by the
+#   Free Software Foundation; either version 2 of the License, or (at your
+#   option) any later version.
+#
+#   This program is distributed in the hope that it will be useful, but
+#   WITHOUT ANY WARRANTY; without even the implied warranty of
+#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General
+#   Public License for more details.
+#
+#   You should have received a copy of the GNU General Public License along
+#   with this program. If not, see <https://www.gnu.org/licenses/>.
+#
+#   As a special exception, the respective Autoconf Macro's copyright owner
+#   gives unlimited permission to copy, distribute and modify the configure
+#   scripts that are the output of Autoconf when processing the Macro. You
+#   need not follow the terms of the GNU General Public License when using
+#   or distributing such scripts, even though portions of the text of the
+#   Macro appear in them. The GNU General Public License (GPL) does govern
+#   all other use of the material that constitutes the Autoconf Macro.
+#
+#   This special exception to the GPL applies to versions of the Autoconf
+#   Macro released by the Autoconf Archive. When you make and distribute a
+#   modified version of the Autoconf Macro, you may extend this special
+#   exception to the GPL to apply to your modified version as well.
+
+#serial 8
+
+AU_ALIAS([TYPE_SOCKLEN_T], [AX_TYPE_SOCKLEN_T])
+AC_DEFUN([AX_TYPE_SOCKLEN_T],
+[AC_CACHE_CHECK([for socklen_t], [ac_cv_ax_type_socklen_t],
+[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[#include <sys/types.h>
+  #include <sys/socket.h>]],
+  [[socklen_t len = (socklen_t) 42; return (!len);]])],
+  [ac_cv_ax_type_socklen_t=yes],
+  [ac_cv_ax_type_socklen_t=no])
+])
+  if test $ac_cv_ax_type_socklen_t != yes; then
+    AC_DEFINE(socklen_t, int, [Substitute for socklen_t])
+  fi
+])

src/eggdrop.h

@@ -269,10 +269,6 @@
 #  define sigemptyset(x) ((*(int *)(x))=0)
 #endif
 
-#ifndef HAVE_SOCKLEN_T
-typedef int socklen_t;
-#endif
-
 #ifdef TLS
 #  include <openssl/ssl.h>
 #endif