Replace most usages of ntoh[ls] and hton[sl] with pg_bswap.h.

All postgres internal usages are replaced, it's just libpq example
usages that haven't been converted. External users of libpq can't
generally rely on including postgres internal headers.

Note that this includes replacing open-coded byte swapping of 64bit
integers (using two 32 bit swaps) with a single 64bit swap.

Where it looked applicable, I have removed netinet/in.h and
arpa/inet.h usage, which previously provided the relevant
functionality. It's perfectly possible that I missed other reasons for
including those, the buildfarm will tell.

Author: Andres Freund
Discussion: https://postgr.es/m/20170927172019.gheidqy6xvlxb325@alap3.anarazel.de

src/interfaces/libpq/fe-connect.c

@@ -47,7 +47,6 @@
 #ifdef HAVE_NETINET_TCP_H
 #include <netinet/tcp.h>
 #endif
-#include <arpa/inet.h>
 #endif
 
 #ifdef ENABLE_THREAD_SAFETY
@@ -73,6 +72,7 @@ static int ldapServiceLookup(const char *purl, PQconninfoOption *options,
 
 #include "common/ip.h"
 #include "mb/pg_wchar.h"
+#include "port/pg_bswap.h"
 
 
 #ifndef WIN32
@@ -2443,7 +2443,7 @@ keep_going:						/* We will come back to here until there is
 					 * shouldn't since we only got here if the socket is
 					 * write-ready.
 					 */
-					pv = htonl(NEGOTIATE_SSL_CODE);
+					pv = pg_hton32(NEGOTIATE_SSL_CODE);
 					if (pqPacketSend(conn, 0, &pv, sizeof(pv)) != STATUS_OK)
 					{
 						appendPQExpBuffer(&conn->errorMessage,
@@ -3838,10 +3838,10 @@ retry3:
 
 	/* Create and send the cancel request packet. */
 
-	crp.packetlen = htonl((uint32) sizeof(crp));
-	crp.cp.cancelRequestCode = (MsgType) htonl(CANCEL_REQUEST_CODE);
-	crp.cp.backendPID = htonl(be_pid);
-	crp.cp.cancelAuthCode = htonl(be_key);
+	crp.packetlen = pg_hton32((uint32) sizeof(crp));
+	crp.cp.cancelRequestCode = (MsgType) pg_hton32(CANCEL_REQUEST_CODE);
+	crp.cp.backendPID = pg_hton32(be_pid);
+	crp.cp.cancelAuthCode = pg_hton32(be_key);
 
 retry4:
 	if (send(tmpsock, (char *) &crp, sizeof(crp), 0) != (int) sizeof(crp))

src/interfaces/libpq/fe-lobj.c

@@ -33,12 +33,11 @@
 #include <fcntl.h>
 #include <limits.h>
 #include <sys/stat.h>
-#include <netinet/in.h>			/* for ntohl/htonl */
-#include <arpa/inet.h>
 
 #include "libpq-fe.h"
 #include "libpq-int.h"
 #include "libpq/libpq-fs.h"		/* must come after sys/stat.h */
+#include "port/pg_bswap.h"
 
 #define LO_BUFSIZE		  8192
 
@@ -1070,11 +1069,11 @@ lo_hton64(pg_int64 host64)
 
 	/* High order half first, since we're doing MSB-first */
 	t = (uint32) (host64 >> 32);
-	swap.i32[0] = htonl(t);
+	swap.i32[0] = pg_hton32(t);
 
 	/* Now the low order half */
 	t = (uint32) host64;
-	swap.i32[1] = htonl(t);
+	swap.i32[1] = pg_hton32(t);
 
 	return swap.i64;
 }
@@ -1095,9 +1094,9 @@ lo_ntoh64(pg_int64 net64)
 
 	swap.i64 = net64;
 
-	result = (uint32) ntohl(swap.i32[0]);
+	result = (uint32) pg_ntoh32(swap.i32[0]);
 	result <<= 32;
-	result |= (uint32) ntohl(swap.i32[1]);
+	result |= (uint32) pg_ntoh32(swap.i32[1]);
 
 	return result;
 }

src/interfaces/libpq/fe-misc.c

@@ -33,9 +33,6 @@
 #include <signal.h>
 #include <time.h>
 
-#include <netinet/in.h>
-#include <arpa/inet.h>
-
 #ifdef WIN32
 #include "win32.h"
 #else
@@ -53,6 +50,7 @@
 #include "libpq-fe.h"
 #include "libpq-int.h"
 #include "mb/pg_wchar.h"
+#include "port/pg_bswap.h"
 #include "pg_config_paths.h"
 
 
@@ -278,14 +276,14 @@ pqGetInt(int *result, size_t bytes, PGconn *conn)
 				return EOF;
 			memcpy(&tmp2, conn->inBuffer + conn->inCursor, 2);
 			conn->inCursor += 2;
-			*result = (int) ntohs(tmp2);
+			*result = (int) pg_ntoh16(tmp2);
 			break;
 		case 4:
 			if (conn->inCursor + 4 > conn->inEnd)
 				return EOF;
 			memcpy(&tmp4, conn->inBuffer + conn->inCursor, 4);
 			conn->inCursor += 4;
-			*result = (int) ntohl(tmp4);
+			*result = (int) pg_ntoh32(tmp4);
 			break;
 		default:
 			pqInternalNotice(&conn->noticeHooks,
@@ -314,12 +312,12 @@ pqPutInt(int value, size_t bytes, PGconn *conn)
 	switch (bytes)
 	{
 		case 2:
-			tmp2 = htons((uint16) value);
+			tmp2 = pg_hton16((uint16) value);
 			if (pqPutMsgBytes((const char *) &tmp2, 2, conn))
 				return EOF;
 			break;
 		case 4:
-			tmp4 = htonl((uint32) value);
+			tmp4 = pg_hton32((uint32) value);
 			if (pqPutMsgBytes((const char *) &tmp4, 4, conn))
 				return EOF;
 			break;
@@ -597,7 +595,7 @@ pqPutMsgEnd(PGconn *conn)
 	{
 		uint32		msgLen = conn->outMsgEnd - conn->outMsgStart;
 
-		msgLen = htonl(msgLen);
+		msgLen = pg_hton32(msgLen);
 		memcpy(conn->outBuffer + conn->outMsgStart, &msgLen, 4);
 	}
 

src/interfaces/libpq/fe-protocol2.c

@@ -19,17 +19,16 @@
 
 #include "libpq-fe.h"
 #include "libpq-int.h"
+#include "port/pg_bswap.h"
 
 
 #ifdef WIN32
 #include "win32.h"
 #else
 #include <unistd.h>
-#include <netinet/in.h>
 #ifdef HAVE_NETINET_TCP_H
 #include <netinet/tcp.h>
 #endif
-#include <arpa/inet.h>
 #endif
 
 
@@ -1609,7 +1608,7 @@ pqBuildStartupPacket2(PGconn *conn, int *packetlen,
 
 	MemSet(startpacket, 0, sizeof(StartupPacket));
 
-	startpacket->protoVersion = htonl(conn->pversion);
+	startpacket->protoVersion = pg_hton32(conn->pversion);
 
 	/* strncpy is safe here: postmaster will handle full fields correctly */
 	strncpy(startpacket->user, conn->pguser, SM_USER);

src/interfaces/libpq/fe-protocol3.c

@@ -21,16 +21,15 @@
 #include "libpq-int.h"
 
 #include "mb/pg_wchar.h"
+#include "port/pg_bswap.h"
 
 #ifdef WIN32
 #include "win32.h"
 #else
 #include <unistd.h>
-#include <netinet/in.h>
 #ifdef HAVE_NETINET_TCP_H
 #include <netinet/tcp.h>
 #endif
-#include <arpa/inet.h>
 #endif
 
 
@@ -2148,7 +2147,7 @@ build_startup_packet(const PGconn *conn, char *packet,
 	/* Protocol version comes first. */
 	if (packet)
 	{
-		ProtocolVersion pv = htonl(conn->pversion);
+		ProtocolVersion pv = pg_hton32(conn->pversion);
 
 		memcpy(packet + packet_len, &pv, sizeof(ProtocolVersion));
 	}