Remove configure probe for netinet/tcp.h.

<netinet/tcp.h> is in SUSv3 and all targeted Unix systems have it.
For Windows, we can provide a stub include file, to avoid some #ifdef
noise.

Discussion: https://postgr.es/m/CA+hUKGKErNfhmvb_H0UprEmp4LPzGN06yR2_0tYikjzB-2ECMw@mail.gmail.com

Author: macdice

configure

@@ -13761,7 +13761,7 @@ $as_echo "#define HAVE_STDBOOL_H 1" >>confdefs.h
 fi
 
 
-for ac_header in atomic.h copyfile.h execinfo.h getopt.h ifaddrs.h langinfo.h mbarrier.h netinet/tcp.h sys/epoll.h sys/event.h sys/personality.h sys/prctl.h sys/procctl.h sys/signalfd.h sys/ucred.h termios.h ucred.h
+for ac_header in atomic.h copyfile.h execinfo.h getopt.h ifaddrs.h langinfo.h mbarrier.h sys/epoll.h sys/event.h sys/personality.h sys/prctl.h sys/procctl.h sys/signalfd.h sys/ucred.h termios.h ucred.h
 do :
   as_ac_Header=`$as_echo "ac_cv_header_$ac_header" | $as_tr_sh`
 ac_fn_c_check_header_mongrel "$LINENO" "$ac_header" "$as_ac_Header" "$ac_includes_default"

configure.ac

@@ -1450,7 +1450,6 @@ AC_CHECK_HEADERS(m4_normalize([
 	ifaddrs.h
 	langinfo.h
 	mbarrier.h
-	netinet/tcp.h
 	sys/epoll.h
 	sys/event.h
 	sys/personality.h

src/backend/libpq/be-secure-openssl.c

@@ -24,10 +24,8 @@
 #include <unistd.h>
 #include <netdb.h>
 #include <netinet/in.h>
-#ifdef HAVE_NETINET_TCP_H
 #include <netinet/tcp.h>
 #include <arpa/inet.h>
-#endif
 
 #include "libpq/libpq.h"
 #include "miscadmin.h"

src/backend/libpq/be-secure.c

@@ -24,10 +24,8 @@
 #include <sys/socket.h>
 #include <netdb.h>
 #include <netinet/in.h>
-#ifdef HAVE_NETINET_TCP_H
 #include <netinet/tcp.h>
 #include <arpa/inet.h>
-#endif
 
 #include "libpq/libpq.h"
 #include "miscadmin.h"

src/backend/libpq/ifaddr.c

@@ -24,9 +24,7 @@
 #include <sys/socket.h>
 #include <netdb.h>
 #include <netinet/in.h>
-#ifdef HAVE_NETINET_TCP_H
 #include <netinet/tcp.h>
-#endif
 #include <sys/file.h>
 
 #include "libpq/ifaddr.h"

src/backend/libpq/pqcomm.c

@@ -67,9 +67,7 @@
 #include <sys/time.h>
 #include <netdb.h>
 #include <netinet/in.h>
-#ifdef HAVE_NETINET_TCP_H
 #include <netinet/tcp.h>
-#endif
 #include <utime.h>
 #ifdef _MSC_VER					/* mstcpip.h is missing on mingw */
 #include <mstcpip.h>

src/common/ip.c

@@ -28,9 +28,7 @@
 #include <sys/socket.h>
 #include <netdb.h>
 #include <netinet/in.h>
-#ifdef HAVE_NETINET_TCP_H
 #include <netinet/tcp.h>
-#endif
 #include <arpa/inet.h>
 #include <sys/file.h>
 

src/include/libpq/libpq-be.h

@@ -23,9 +23,7 @@
 #include <openssl/ssl.h>
 #include <openssl/err.h>
 #endif
-#ifdef HAVE_NETINET_TCP_H
 #include <netinet/tcp.h>
-#endif
 
 #ifdef ENABLE_GSS
 #if defined(HAVE_GSSAPI_H)

src/include/pg_config.h.in

@@ -322,9 +322,6 @@
 /* Define to 1 if you have the `mkdtemp' function. */
 #undef HAVE_MKDTEMP
 
-/* Define to 1 if you have the <netinet/tcp.h> header file. */
-#undef HAVE_NETINET_TCP_H
-
 /* Define to 1 if you have the `OPENSSL_init_ssl' function. */
 #undef HAVE_OPENSSL_INIT_SSL
 

src/include/port/win32/netinet/tcp.h

@@ -0,0 +1,7 @@
+/* src/include/port/win32/netinet/tcp.h */
+#ifndef WIN32_NETINET_TCP_H
+#define WIN32_NETINET_TCP_H
+
+#include <sys/socket.h>
+
+#endif