From: Niels Provos <provos@gmail.com>
Date: Tue, 23 Mar 2004 04:05:37 +0000 (+0000)
Subject: allow the write callback to called even if there is no buffered data
X-Git-Tag: release-1.1b~73
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=246d8583c08dc31d70479d538c8b1f4056f49c43;p=libevent

allow the write callback to called even if there is no buffered data


svn:r96
---

diff --git a/evbuffer.c b/evbuffer.c
index 80e73187..d765ce5f 100644
--- a/evbuffer.c
+++ b/evbuffer.c
@@ -85,7 +85,7 @@ static void
 bufferevent_writecb(int fd, short event, void *arg)
 {
 	struct bufferevent *bufev = arg;
-	int res;
+	int res = 0;
 	short what = EVBUFFER_WRITE;
 
 	if (event == EV_TIMEOUT) {
@@ -93,29 +93,33 @@ bufferevent_writecb(int fd, short event, void *arg)
 		goto error;
 	}
 
-	res = evbuffer_write(bufev->input, fd);
-	if (res == -1) {
-		if (errno == EAGAIN || errno == EINTR)
-			goto reschedule;
-		/* error case */
-		what |= EVBUFFER_ERROR;
-	} else if (res == 0) {
-		/* eof case */
-		what |= EVBUFFER_EOF;
+	if (EVBUFFER_LENGTH(bufev->output)) {
+	    res = evbuffer_write(bufev->output, fd);
+	    if (res == -1) {
+		    if (errno == EAGAIN || errno == EINTR)
+			    goto reschedule;
+		    /* error case */
+		    what |= EVBUFFER_ERROR;
+	    } else if (res == 0) {
+		    /* eof case */
+		    what |= EVBUFFER_EOF;
+	    }
+	    if (res <= 0)
+		    goto error;
 	}
 
-	if (res <= 0)
-		goto error;
+	if (EVBUFFER_LENGTH(bufev->output) != 0)
+		bufferevent_add(&bufev->ev_write, bufev->timeout_write);
 
 	/* Invoke the user callback if our buffer is drained */
 	if (EVBUFFER_LENGTH(bufev->output) == 0)
 		(*bufev->writecb)(bufev, bufev->cbarg);
 
+	return;
+
  reschedule:
-	/* Do not call if we call user callback before, we may be deleted */
-	if (EVBUFFER_LENGTH(bufev->output) != 0) {
+	if (EVBUFFER_LENGTH(bufev->output) != 0)
 		bufferevent_add(&bufev->ev_write, bufev->timeout_write);
-	}
 	return;
 
  error:
diff --git a/event.h b/event.h
index ebb71653..dd03c538 100644
--- a/event.h
+++ b/event.h
@@ -175,6 +175,7 @@ struct evbuffer {
 	size_t off;
 };
 
+/* Just for error reporting - use other constants otherwise */
 #define EVBUFFER_READ		0x01
 #define EVBUFFER_WRITE		0x02
 #define EVBUFFER_EOF		0x10