1 files changed, 76 insertions, 0 deletions
diff --git a/m4/socklen.m4 b/m4/socklen.m4
new file mode 100644
index 0000000..1390ac4
--- /dev/null
+++ b/m4/socklen.m4
@@ -0,0 +1,76 @@
+# socklen.m4 serial 11
+dnl Copyright (C) 2005-2007, 2009-2022 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.
+
+dnl From Albert Chin, Windows fixes from Simon Josefsson.
+
+dnl Check for socklen_t: historically on BSD it is an int, and in
+dnl POSIX 1g it is a type of its own, but some platforms use different
+dnl types for the argument to getsockopt, getpeername, etc.:
+dnl HP-UX 10.20, IRIX 6.5, OSF/1 4.0, Interix 3.5, BeOS.
+dnl So we have to test to find something that will work.
+
+AC_DEFUN([gl_TYPE_SOCKLEN_T],
+  [AC_REQUIRE([gl_CHECK_SOCKET_HEADERS])dnl
+   AC_CHECK_TYPE([socklen_t], ,
+     [AC_CACHE_CHECK([for socklen_t equivalent],
+        [gl_cv_socklen_t_equiv],
+        [# Systems have either "struct sockaddr *" or
+         # "void *" as the second argument to getpeername
+         gl_cv_socklen_t_equiv=
+         for arg2 in "struct sockaddr" void; do
+           for t in int size_t "unsigned int" "long int" "unsigned long int"; do
+             AC_COMPILE_IFELSE([AC_LANG_PROGRAM(
+                 [[#include <sys/types.h>
+                   #include <sys/socket.h>
+
+                   int getpeername (int, $arg2 *, $t *);]],
+                 [[$t len;
+                  getpeername (0, 0, &len);]])],
+               [gl_cv_socklen_t_equiv="$t"])
+             test "$gl_cv_socklen_t_equiv" != "" && break
+           done
+           test "$gl_cv_socklen_t_equiv" != "" && break
+         done
+         if test "$gl_cv_socklen_t_equiv" = ""; then
+           AC_MSG_ERROR([Cannot find a type to use in place of socklen_t])
+         fi
+        ])
+      AC_DEFINE_UNQUOTED([socklen_t], [$gl_cv_socklen_t_equiv],
+        [type to use in place of socklen_t if not defined])],
+     [gl_SOCKET_HEADERS])])
+
+dnl On mingw32, socklen_t is in ws2tcpip.h ('int'), so we try to find
+dnl it there too.  But on Cygwin, wc2tcpip.h must not be included.  Users
+dnl of this module should use the same include pattern as gl_SOCKET_HEADERS.
+dnl When you change this macro, keep also in sync:
+dnl   - gl_CHECK_SOCKET_HEADERS,
+dnl   - the Include section of modules/socklen.
+AC_DEFUN([gl_SOCKET_HEADERS],
+[
+/* <sys/types.h> is not needed according to POSIX, but the
+   <sys/socket.h> in i386-unknown-freebsd4.10 and
+   powerpc-apple-darwin5.5 required it. */
+#include <sys/types.h>
+#if HAVE_SYS_SOCKET_H
+# include <sys/socket.h>
+#elif HAVE_WS2TCPIP_H
+# include <ws2tcpip.h>
+#endif
+])
+
+dnl Tests for the existence of the header for socket facilities.
+dnl Defines the C macros HAVE_SYS_SOCKET_H, HAVE_WS2TCPIP_H.
+dnl This macro must match gl_SOCKET_HEADERS.
+AC_DEFUN([gl_CHECK_SOCKET_HEADERS],
+  [AC_CHECK_HEADERS_ONCE([sys/socket.h])
+   if test $ac_cv_header_sys_socket_h = no; then
+     dnl We cannot use AC_CHECK_HEADERS_ONCE here, because that would make
+     dnl the check for those headers unconditional; yet cygwin reports
+     dnl that the headers are present but cannot be compiled (since on
+     dnl cygwin, all socket information should come from sys/socket.h).
+     AC_CHECK_HEADERS([ws2tcpip.h])
+   fi
+  ])