From: Egor <egor@patchysicp.xyz>
Date: Thu, 19 Oct 2023 13:59:50 +0000 (+0300)
Subject: killConnection: never block
X-Git-Url: https://git.patchysicp.xyz/?a=commitdiff_plain;h=b7727940cb1f07e4f7c285cb086d9b7645c1b824;p=patchyircd.git

killConnection: never block
---

diff --git a/src/common.h b/src/common.h
index 4750193..f857071 100644
--- a/src/common.h
+++ b/src/common.h
@@ -56,6 +56,8 @@ struct client_data {
 	unsigned want_write_for_read :1;
 	unsigned want_read_for_write :1;
 	unsigned want_write_for_write :1;
+	unsigned want_read_for_close :1;
+	unsigned want_write_for_close :1;
 };
 struct channel {
 	char *key;
diff --git a/src/main.c b/src/main.c
index fc9d75e..97dcffa 100644
--- a/src/main.c
+++ b/src/main.c
@@ -323,8 +323,9 @@ int main(int argc, char *argv[])
 			FD_SET(self_sock, &readfds);
 #endif
 		for (struct client_data *cl = clients; cl; cl = cl->next) {
-			FD_SET(cl->FD, &readfds);
-			if (cl->want_write_for_read || cl->want_write_for_write)
+			if (!cl->want_write_for_close)
+				FD_SET(cl->FD, &readfds);
+			if (cl->want_write_for_read || cl->want_write_for_write || cl->want_write_for_close)
 				FD_SET(cl->FD, &writefds);
 		}
 
@@ -365,10 +366,13 @@ int main(int argc, char *argv[])
 			struct client_data *next = cl->next;
 			int isr = FD_ISSET(cl->FD, &readfds);
 			int isw = FD_ISSET(cl->FD, &writefds);
-			if (isr || (cl->want_write_for_read && isw))
-				recvProc(cl);
+			if (!cl->want_read_for_close && !cl->want_write_for_close)
+				if (isr || (cl->want_write_for_read && isw))
+					recvProc(cl);
 			if ((cl->want_read_for_write && isr) || (cl->want_write_for_write && isw))
 				sendClient(cl, 0, 0);
+			if ((cl->want_read_for_close && isr) || (cl->want_write_for_close && isw))
+				killConnectionPart2(cl);
 			cl = next;
 		}
 	}
@@ -377,6 +381,8 @@ int main(int argc, char *argv[])
 	for (struct client_data *cl = clients; cl;) {
 		struct client_data *next = cl->next;
 		killConnection(cl, 0);
+		/* FIXME: who is going to wait for these connections to actually get
+		 * killed? */
 		cl = next;
 	}
 	net_cleanup();
diff --git a/src/net.c b/src/net.c
index 906bfc8..e17a167 100644
--- a/src/net.c
+++ b/src/net.c
@@ -7,34 +7,9 @@ struct client_data *allocClient()
 	return calloc(1, sizeof(struct client_data));
 }
 
-#ifdef HAS_TLS
-static void block(struct client_data *cl, int out)
+void killConnection(struct client_data *cl, int byChoice)
 {
-#ifdef _WIN32
-	fd_set fds;
-	FD_ZERO(&fds);
-	FD_SET(cl->FD, &fds);
-	if (out)
-		select(cl->FD+1, 0, &fds, 0, 0);
-	else
-		select(cl->FD+1, &fds, 0, 0, 0);
-#else
-	struct pollfd pfd;
-	pfd.fd = cl->FD;
-	pfd.events = out ? POLLOUT : POLLIN;
-	poll(&pfd, 1, 0);
-#endif
-}
-#endif
-
-void killConnection(struct client_data *cl, int byChoice) {
 	if (!cl) return;
-	for (struct client_data **next = &clients; *next; next = &(*next)->next) {
-		if (*next == cl) {
-			*next = cl->next;
-			break;
-		}
-	}
 	if (cl->peername)
 		fprintf(stderr, "Client disconnected from Socket: %"PRISocket", IP: %s PORT: %d\n", cl->FD, cl->peername, cl->peerport);
 	if(!byChoice && cl->nick && cl->username) {
@@ -44,17 +19,27 @@ void killConnection(struct client_data *cl, int byChoice) {
 	// Send error to client informing them that they will be disconnected
 	msg_error("Closing Link");
 	sendbuf(cl);
+	killConnectionPart2(cl);
+}
+void killConnectionPart2(struct client_data *cl)
+{
+	/* FIXME: we have to flush existing data somehow */
+	/* A better implementation would be to keep a separate list of disconnected
+	 * clients. This way we can do all PARTing right away and only concern
+	 * ourselves with tls_write/tls_close. */
+	cl->want_read_for_close = 0;
+	cl->want_write_for_close = 0;
 	if (cl->FD != INVALID_SOCKET) {
 #ifdef HAS_TLS
 		if (cl->cctx) {
-			// FIXME: this blocks
-			int rv;
-			for (;;) {
-				rv = tls_close(cl->cctx);
-				if (rv == TLS_WANT_POLLIN || rv == TLS_WANT_POLLOUT)
-					block(cl, rv == TLS_WANT_POLLOUT);
-				else
-					break;
+			int rv = tls_close(cl->cctx);
+			if (rv == TLS_WANT_POLLIN) {
+				cl->want_read_for_close = 1;
+				return;
+			}
+			if (rv == TLS_WANT_POLLOUT) {
+				cl->want_write_for_close = 1;
+				return;
 			}
 			if (rv == -1) {
 				fprintf(stderr, "tls_close (%"PRISocket"): %s\n", cl->FD, tls_error(cl->cctx));
@@ -66,6 +51,12 @@ void killConnection(struct client_data *cl, int byChoice) {
 		shutdown(cl->FD, SHUT_RDWR);
 		closesocket(cl->FD);
 	}
+	for (struct client_data **next = &clients; *next; next = &(*next)->next) {
+		if (*next == cl) {
+			*next = cl->next;
+			break;
+		}
+	}
 	struct trie_find *f = NULL;
 	if (trie_findfirst(&f, &cl->channels) == 1)
 		do {
diff --git a/src/net.h b/src/net.h
index c147b03..d0d4bde 100644
--- a/src/net.h
+++ b/src/net.h
@@ -6,6 +6,7 @@ void sendbuf(struct client_data *client);
 void sendbuf_visible(struct client_data *client);
 struct client_data *allocClient();
 void killConnection(struct client_data *client, int byChoice);
+void killConnectionPart2(struct client_data *cl);
 void recvProc(struct client_data *cl);
 void sendClient(struct client_data *cl, const char *buf, size_t len);