From: Egor <egor@patchysicp.xyz>
Date: Wed, 18 Oct 2023 20:00:17 +0000 (+0300)
Subject: sendClient: never block
X-Git-Url: https://git.patchysicp.xyz/?a=commitdiff_plain;h=5c16fd843059d825acb622460131932dadaab4f0;p=patchyircd.git

sendClient: never block
---

diff --git a/common.h b/common.h
index 3c5243b..6681546 100644
--- a/common.h
+++ b/common.h
@@ -43,6 +43,8 @@ struct client_data {
 	unsigned short peerport;
 	char   buf[2048];
 	size_t bufLen;
+	char   wbuf[8192];
+	size_t wbufLen;
 	char   umode;
 	char   regstate;
 	struct trie_node *channels;
@@ -51,7 +53,9 @@ struct client_data {
 	time_t signon;
 	time_t lastactivity;
 	unsigned int caps;
-	char   want_write_for_read;
+	char   want_write_for_read :1;
+	char   want_read_for_write :1;
+	char   want_write_for_write :1;
 };
 struct channel {
 	char *key;
diff --git a/main.c b/main.c
index b7f1743..c00c1ac 100644
--- a/main.c
+++ b/main.c
@@ -321,7 +321,7 @@ int main(int argc, char *argv[])
 #endif
 		for (struct client_data *cl = clients; cl; cl = cl->next) {
 			FD_SET(cl->FD, &readfds);
-			if (cl->want_write_for_read)
+			if (cl->want_write_for_read || cl->want_write_for_write)
 				FD_SET(cl->FD, &writefds);
 		}
 
@@ -360,8 +360,12 @@ int main(int argc, char *argv[])
 		// Respond to already connected clients
 		for (struct client_data *cl = clients; cl;) {
 			struct client_data *next = cl->next;
-			if (FD_ISSET(cl->FD, &readfds) || (cl->want_write_for_read && FD_ISSET(cl->FD, &writefds)))
+			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_write && isr) || (cl->want_write_for_write && isw))
+				sendClient(cl, 0, 0);
 			cl = next;
 		}
 	}
diff --git a/net.c b/net.c
index 76c91e6..90d4c3c 100644
--- a/net.c
+++ b/net.c
@@ -12,6 +12,26 @@ struct client_data *allocClient(){
 	return NewClient;
 };
 
+#ifdef HAS_TLS
+static void block(struct client_data *cl, int out)
+{
+#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, bool byChoice) {
 	if (!cl) return;
 	for (struct client_data **next = &clients; *next; next = &(*next)->next) {
@@ -34,9 +54,13 @@ void killConnection(struct client_data *cl, bool byChoice) {
 		if (cl->cctx) {
 			// FIXME: this blocks
 			int rv;
-			do {
+			for (;;) {
 				rv = tls_close(cl->cctx);
-			} while (rv == TLS_WANT_POLLIN || rv == TLS_WANT_POLLOUT);
+				if (rv == TLS_WANT_POLLIN || rv == TLS_WANT_POLLOUT)
+					block(cl, rv == TLS_WANT_POLLOUT);
+				else
+					break;
+			}
 			if (rv == -1) {
 				fprintf(stderr, "tls_close (%"PRISocket"): %s\n", cl->FD, tls_error(cl->cctx));
 			}
@@ -78,24 +102,6 @@ void killConnection(struct client_data *cl, bool byChoice) {
 	free(cl);
 }
 
-static void block(struct client_data *cl, int out)
-{
-#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
-}
-
 void recvProc(struct client_data *cl) {
 	ssize_t bytesRead;
 	char *x;
@@ -157,24 +163,27 @@ void recvProc(struct client_data *cl) {
 	}
 }
 
-void sendClient(struct client_data *cl, const char *buf, size_t len)
+/* returns the count of bytes which were not sent */
+static int sendClientRaw(struct client_data *cl, const char *buf, size_t len)
 {
+	cl->want_read_for_write = 0;
+	cl->want_write_for_write = 0;
 	if (cl->FD == (SOCKET)INVALID_SOCKET)
-		return;
+		return 0;
 	fprintf(stderr, "SERVER %"PRISocket": %.*s", cl->FD, (int)len, (char*)buf);
-	// TODO: error handling
-	// FIXME: blocks, probably the reason why server is slow
+	/* FIXME: error handling */
 #ifdef HAS_TLS
 	if (cl->cctx) {
 		while (len) {
 			int rv = tls_write(cl->cctx, buf, len);
-			if (!rv)
-				break;
-			if (rv == -1)
+			if (rv == 0 || rv == -1) {
 				break;
-			if (rv == TLS_WANT_POLLIN || rv == TLS_WANT_POLLOUT) {
-				block(cl, rv == TLS_WANT_POLLOUT);
-				continue;
+			} else if (rv == TLS_WANT_POLLIN) {
+				cl->want_read_for_write = 1;
+				return len;
+			} else if (rv == TLS_WANT_POLLOUT) {
+				cl->want_write_for_write = 1;
+				return len;
 			}
 			buf += rv;
 			len -= rv;
@@ -188,8 +197,8 @@ void sendClient(struct client_data *cl, const char *buf, size_t len)
 				break;
 			if (rv == -1) {
 				if (net_wouldblock()) {
-					block(cl, 1);
-					continue;
+					cl->want_write_for_write = 1;
+					return len;
 				} else {
 					break;
 				}
@@ -198,4 +207,30 @@ void sendClient(struct client_data *cl, const char *buf, size_t len)
 			len -= rv;
 		}
 	}
+	return len;
+}
+
+void sendClient(struct client_data *cl, const char *buf, size_t len)
+{
+	if (cl->wbufLen + len > sizeof(cl->wbuf)) {
+		/* Buffer overrun */
+		/* FIXME: probably should terminate the connection at this point */
+		len = 0;
+		/* we don't return here, because we still want to push old data if possible */
+	}
+	if (!cl->wbufLen) {
+		if (len) {
+			int left = sendClientRaw(cl, buf, len);
+			memcpy(cl->wbuf, buf+len-left, left);
+			cl->wbufLen = left;
+		}
+		return;
+	}
+	if (len) {
+		memcpy(cl->wbuf + cl->wbufLen, buf, len);
+		cl->wbufLen += len;
+	}
+	int left = sendClientRaw(cl, cl->wbuf, cl->wbufLen);
+	memmove(cl->wbuf, cl->wbuf+cl->wbufLen-left, left);
+	cl->wbufLen = left;
 }