Fix select(), add some tests.

Makefile

@@ -46,7 +46,7 @@ BIN_FILES := $(shell cat manifest.bin.txt)
 SRC_FILES := $(shell cat manifest.src.txt)
 
 # Tests to compile before running the test suite.
-TESTS := tests/addr.exe tests/addrcache.exe tests/ethernet.exe
+TESTS := tests/addr.exe tests/addrcache.exe tests/ethernet.exe tools/fionread.exe
 
 # Tools to compile before running the test suite.
 TOOLS := tools/socket.exe tools/list-interfaces.exe tools/bind.exe tools/ipx-send.exe \
@@ -178,6 +178,9 @@ tests/%.o: tests/%.c
 	$(CC) $(CFLAGS) $(DEPFLAGS) -I./ -c -o $@ $<
 	$(DEPPOST)
 
+tools/fionread.exe: tests/fionread.o tests/tap/basic.o src/addr.o
+	$(CC) $(CFLAGS) -o $@ $^ -lwsock32
+
 tools/%.exe: tools/%.o src/addr.o
 	$(CC) $(CFLAGS) -o $@ $^ -lwsock32 -lole32 -lrpcrt4
 

src/ipxwrapper.def

@@ -21,3 +21,4 @@ EXPORTS
 	listen
 	accept
 	WSAAsyncSelect
+	select

src/winsock.c

@@ -2668,6 +2668,8 @@ int WSAAPI select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds
 	fd_set force_read_fds;
 	FD_ZERO(&force_read_fds);
 	
+	if(readfds != NULL)
+	{
 		for(unsigned int i = 0; i < readfds->fd_count; ++i)
 		{
 			int fd = readfds->fd_array[i];
@@ -2683,10 +2685,11 @@ int WSAAPI select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds
 				
 				if(sockptr->recv_queue->n_ready > 0)
 				{
-				/* There is data in the receive queue for this socket, but the
+					/* There is data in the receive queue for this socket, but
-				 * underlying socket isn't necessarily readable, so we reduce the
+					 * the underlying socket isn't necessarily readable, so we
-				 * select() timeout to zero to ensure it returns immediately and
+					 * reduce the select() timeout to zero to ensure it returns
-				 * inject this fd back into readfds at the end if necessary.
+					 * immediately and inject this fd back into readfds at the
+					 * end if necessary.
 					*/
 					
 					FD_SET(fd, &force_read_fds);
@@ -2696,6 +2699,7 @@ int WSAAPI select(int nfds, fd_set *readfds, fd_set *writefds, fd_set *exceptfds
 				unlock_sockets();
 			}
 		}
+	}
 	
 	int r = r_select(nfds, readfds, writefds, exceptfds, (const PTIMEVAL)(use_timeout));
 	

src/wsock32_stubs.txt

@@ -15,7 +15,7 @@ ntohl
 ntohs
 recv:0
 recvfrom:0
-select
+select:0
 send:0
 sendto:0
 setsockopt:0

tests/25-fionread.t

@@ -0,0 +1,34 @@
+# IPXWrapper test suite
+# Copyright (C) 2023 Daniel Collins <solemnwarning@solemnwarning.net>
+#
+# This program is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License version 2 as published by
+# the Free Software Foundation.
+#
+# 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, write to the Free Software Foundation, Inc., 51
+# Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+
+use strict;
+use warnings;
+
+use FindBin;
+use lib "$FindBin::Bin/lib/";
+
+use IPXWrapper::Util;
+
+require "$FindBin::Bin/config.pm";
+our ($remote_mac_a, $remote_ip_a);
+
+reg_delete_key($remote_ip_a, "HKCU\\Software\\IPXWrapper");
+
+# Unit tests implemented by fionread.exe, so run it on the test system and pass
+# the (TAP) output/exit status to our parent.
+
+system("ssh", $remote_ip_a, "Z:\\tools\\fionread.exe", "00:00:00:01", $remote_mac_a);
+exit($? >> 8);

tests/fionread.c

@@ -0,0 +1,134 @@
+/* IPXWrapper test suite
+ * Copyright (C) 2023 Daniel Collins <solemnwarning@solemnwarning.net>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 as published by
+ * the Free Software Foundation.
+ *
+ * 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, write to the Free Software Foundation, Inc., 51
+ * Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
+*/
+
+#include <assert.h>
+#include <stdio.h>
+
+#include <winsock2.h>
+#include <windows.h>
+#include <wsipx.h>
+
+#include "tap/basic.h"
+#include "../tools/tools.h"
+
+static char buf[4096];
+
+int main(int argc, char **argv)
+{
+	if(argc != 3)
+	{
+		fprintf(stderr, "Usage: %s <netnum> <nodenum>\n", argv[0]);
+		return 1;
+	}
+	
+	plan_lazy();
+	
+	struct sockaddr_ipx addr1 = read_sockaddr(argv[1], argv[2], "1234");
+	struct sockaddr_ipx addr2 = read_sockaddr(argv[1], argv[2], "1235");
+	
+	WSADATA data;
+	WSAStartup(MAKEWORD(1, 1), &data);
+	
+	int sock1 = socket(AF_IPX, SOCK_DGRAM, NSPROTO_IPX);
+	assert(sock1 != SOCKET_ERROR);
+	
+	assert(bind(sock1, (struct sockaddr*)(&addr1), sizeof(addr1)) == 0);
+	
+	int sock2 = socket(AF_IPX, SOCK_DGRAM, NSPROTO_IPX);
+	assert(sock2 != SOCKET_ERROR);
+	
+	assert(bind(sock2, (struct sockaddr*)(&addr2), sizeof(addr2)) == 0);
+	
+	fd_set readfds;
+	struct timeval timeout = { 0, 0 };
+	
+	unsigned long x = 123456789;
+	int r = ioctlsocket(sock1, FIONREAD, &x);
+	
+	is_int(0, r, "ioctlsocket(FIONREAD) succeeds when no packets are waiting");
+	is_int(0, x, "ioctlsocket(FIONREAD) returns zero bytes when no packets are waiting");
+	
+	FD_ZERO(&readfds);
+	FD_SET(sock1, &readfds);
+	is_int(select(-1, &readfds, NULL, NULL, &timeout), 0, "select() initially indicates socket is not ready to read");
+	ok(!FD_ISSET(sock1, &readfds), "select() initially indicates socket is not ready to read");
+	
+	assert(sendto(sock2, buf, 128, 0, (struct sockaddr*)(&addr1), sizeof(addr1)) == 128);
+	
+	/* Just in case there's any async going on */
+	Sleep(100);
+	
+	FD_ZERO(&readfds);
+	FD_SET(sock1, &readfds);
+	is_int(select(-1, &readfds, NULL, NULL, &timeout), 1, "select() indicates socket is ready to read before call to ioctlsocket(FIONREAD)");
+	ok(FD_ISSET(sock1, &readfds), "select() indicates socket is ready to read before call to ioctlsocket(FIONREAD)");
+	
+	x = 123456789;
+	r = ioctlsocket(sock1, FIONREAD, &x);
+	
+	is_int(0, r, "ioctlsocket(FIONREAD) succeeds when packets are waiting");
+	is_int(128, x, "ioctlsocket(FIONREAD) returns payload size when one packet is waiting");
+	
+	FD_ZERO(&readfds);
+	FD_SET(sock1, &readfds);
+	is_int(select(-1, &readfds, NULL, NULL, &timeout), 1, "select() indicates socket is ready to read after call to ioctlsocket(FIONREAD)");
+	ok(FD_ISSET(sock1, &readfds), "select() indicates socket is ready to read after call to ioctlsocket(FIONREAD)");
+	
+	assert(sendto(sock2, buf, 256, 0, (struct sockaddr*)(&addr1), sizeof(addr1)) == 256);
+	
+	/* Just in case there's any async going on */
+	Sleep(100);
+	
+	x = 123456789;
+	r = ioctlsocket(sock1, FIONREAD, &x);
+	
+	is_int(0, r, "ioctlsocket(FIONREAD) succeeds when packets are waiting");
+	is_int(384, x, "ioctlsocket(FIONREAD) returns combined payload sizes when multiple packets are waiting");
+	
+	assert(recv(sock1, buf, 4096, 0) == 128);
+	
+	FD_ZERO(&readfds);
+	FD_SET(sock1, &readfds);
+	is_int(select(-1, &readfds, NULL, NULL, &timeout), 1, "select() indicates socket is ready to read after reading first packet");
+	ok(FD_ISSET(sock1, &readfds), "select() indicates socket is ready to read after reading first packet");
+	
+	x = 123456789;
+	r = ioctlsocket(sock1, FIONREAD, &x);
+	
+	is_int(0, r, "ioctlsocket(FIONREAD) succeeds when packets are waiting");
+	is_int(256, x, "ioctlsocket(FIONREAD) returns payload sizes when one packet is waiting");
+	
+	assert(recv(sock1, buf, 4096, 0) == 256);
+	
+	FD_ZERO(&readfds);
+	FD_SET(sock1, &readfds);
+	is_int(select(-1, &readfds, NULL, NULL, &timeout), 0, "select() indicates socket is not ready to read after reading second packet");
+	ok(!FD_ISSET(sock1, &readfds), "select() indicates socket is ready to read after reading second packet");
+	
+	x = 123456789;
+	r = ioctlsocket(sock1, FIONREAD, &x);
+	
+	is_int(0, r, "ioctlsocket(FIONREAD) succeeds when no packets are waiting");
+	is_int(0, x, "ioctlsocket(FIONREAD) returns zero bytes when no packets are waiting");
+	
+	closesocket(sock2);
+	closesocket(sock1);
+	
+	WSACleanup();
+	
+	return 0;
+}

tools/tools.h

@@ -8,7 +8,7 @@
 #include <stdlib.h>
 #include <string.h>
 
-#include "addr.h"
+#include "../src/addr.h"
 
 static struct sockaddr_ipx read_sockaddr(const char *net_s, const char *node_s, const char *socket_s)
 {