From b9a7444b9fa216d16d91f34d2e12f51fc4d60e46 Mon Sep 17 00:00:00 2001
From: Kirill Isakov <bootctl@gmail.com>
Date: Sat, 2 Apr 2022 17:41:50 +0600
Subject: [PATCH] Correct close() function when building with MSVC

The original close() was throwing assertion errors from inside the
Windows libraries because we were trying to close OS handles as file
descriptors.
---
 src/dropin.h     |  1 +
 src/net_packet.c |  6 +++---
 src/net_setup.c  |  6 +++---
 src/route.c      |  4 ++--
 src/tincctl.c    | 16 ++++++++--------
 5 files changed, 17 insertions(+), 16 deletions(-)

diff --git a/src/dropin.h b/src/dropin.h
index da10cd9a..384b4dbf 100644
--- a/src/dropin.h
+++ b/src/dropin.h
@@ -76,6 +76,7 @@ extern int gettimeofday(struct timeval *, void *);
 #define PATH_MAX MAX_PATH
 #define strcasecmp _stricmp
 #define strncasecmp _strnicmp
+#define close CloseHandle
 #define __const const
 
 typedef int mode_t;
diff --git a/src/net_packet.c b/src/net_packet.c
index 5bdcb1aa..d171fec6 100644
--- a/src/net_packet.c
+++ b/src/net_packet.c
@@ -1257,7 +1257,7 @@ static length_t choose_initial_maxmtu(node_t *n) {
 
 	if(connect(sock, &sa->sa, SALEN(sa->sa))) {
 		logger(DEBUG_TRAFFIC, LOG_ERR, "Connecting MTU assessment socket for %s (%s) failed: %s", n->name, n->hostname, sockstrerror(sockerrno));
-		close(sock);
+		closesocket(sock);
 		return MTU;
 	}
 
@@ -1266,11 +1266,11 @@ static length_t choose_initial_maxmtu(node_t *n) {
 
 	if(getsockopt(sock, IPPROTO_IP, IP_MTU, (void *)&ip_mtu, &ip_mtu_len)) {
 		logger(DEBUG_TRAFFIC, LOG_ERR, "getsockopt(IP_MTU) on %s (%s) failed: %s", n->name, n->hostname, sockstrerror(sockerrno));
-		close(sock);
+		closesocket(sock);
 		return MTU;
 	}
 
-	close(sock);
+	closesocket(sock);
 
 	if(ip_mtu < MINMTU) {
 		logger(DEBUG_TRAFFIC, LOG_ERR, "getsockopt(IP_MTU) on %s (%s) returned absurdly small value: %d", n->name, n->hostname, ip_mtu);
diff --git a/src/net_setup.c b/src/net_setup.c
index 43895dda..60fc692d 100644
--- a/src/net_setup.c
+++ b/src/net_setup.c
@@ -606,7 +606,7 @@ static bool add_listen_address(char *address, bool bindto) {
 		int udp_fd = setup_vpn_in_socket((sockaddr_t *) aip->ai_addr);
 
 		if(udp_fd < 0) {
-			close(tcp_fd);
+			closesocket(tcp_fd);
 			continue;
 		}
 
@@ -1180,8 +1180,8 @@ void close_network_connections(void) {
 	for(int i = 0; i < listen_sockets; i++) {
 		io_del(&listen_socket[i].tcp);
 		io_del(&listen_socket[i].udp);
-		close(listen_socket[i].tcp.fd);
-		close(listen_socket[i].udp.fd);
+		closesocket(listen_socket[i].tcp.fd);
+		closesocket(listen_socket[i].udp.fd);
 	}
 
 	exit_requests();
diff --git a/src/route.c b/src/route.c
index 25f2be5e..6f1ffd4c 100644
--- a/src/route.c
+++ b/src/route.c
@@ -164,7 +164,7 @@ static void route_ipv4_unreachable(node_t *source, vpn_packet_t *packet, length_
 				}
 			}
 
-			close(sockfd);
+			closesocket(sockfd);
 		}
 	}
 
@@ -269,7 +269,7 @@ static void route_ipv6_unreachable(node_t *source, vpn_packet_t *packet, length_
 				}
 			}
 
-			close(sockfd);
+			closesocket(sockfd);
 		}
 	}
 
diff --git a/src/tincctl.c b/src/tincctl.c
index c700f947..5ae76d31 100644
--- a/src/tincctl.c
+++ b/src/tincctl.c
@@ -644,7 +644,7 @@ static bool stop_tincd(void) {
 		// wait for tincd to close the connection...
 	}
 
-	close(fd);
+	closesocket(fd);
 	pid = 0;
 	fd = -1;
 
@@ -717,7 +717,7 @@ bool connect_tincd(bool verbose) {
 
 		if(select(fd + 1, &r, NULL, NULL, &tv)) {
 			fprintf(stderr, "Previous connection to tincd lost, reconnecting.\n");
-			close(fd);
+			closesocket(fd);
 			fd = -1;
 		} else {
 			return true;
@@ -784,7 +784,7 @@ bool connect_tincd(bool verbose) {
 			fprintf(stderr, "Cannot connect to UNIX socket %s: %s\n", unixsocketname, sockstrerror(sockerrno));
 		}
 
-		close(fd);
+		closesocket(fd);
 		fd = -1;
 		return false;
 	}
@@ -830,7 +830,7 @@ bool connect_tincd(bool verbose) {
 			fprintf(stderr, "Cannot connect to %s port %s: %s\n", host, port, sockstrerror(sockerrno));
 		}
 
-		close(fd);
+		closesocket(fd);
 		fd = -1;
 		return false;
 	}
@@ -853,7 +853,7 @@ bool connect_tincd(bool verbose) {
 			fprintf(stderr, "Cannot read greeting from control socket: %s\n", sockstrerror(sockerrno));
 		}
 
-		close(fd);
+		closesocket(fd);
 		fd = -1;
 		return false;
 	}
@@ -863,7 +863,7 @@ bool connect_tincd(bool verbose) {
 			fprintf(stderr, "Could not fully establish control socket connection\n");
 		}
 
-		close(fd);
+		closesocket(fd);
 		fd = -1;
 		return false;
 	}
@@ -1528,7 +1528,7 @@ static int cmd_log(int argc, char *argv[]) {
 	signal(SIGINT, SIG_DFL);
 #endif
 
-	close(fd);
+	closesocket(fd);
 	fd = -1;
 	return 0;
 }
@@ -2623,7 +2623,7 @@ static int switch_network(char *name) {
 	}
 
 	if(fd >= 0) {
-		close(fd);
+		closesocket(fd);
 		fd = -1;
 	}
 
-- 
2.20.1