From d2feeee1d6badd4f2da90d8bea29f58e77e0d68b Mon Sep 17 00:00:00 2001
From: Andy Green <andy@warmcat.com>
Date: Thu, 5 May 2016 09:23:05 +0800
Subject: [PATCH] recv revert treating zero as hangup
While checking with ab, I found
commit 30cdb3ac8f24a4c289a3b4e8a41d6c5f2e6ec959
Author: Justin Chen <justinchen00@github.invalid.com>
Date: Thu Apr 14 21:40:53 2016 +0800
recv treat zero return as error
https://github.com/warmcat/libwebsockets/issues/475
turned ab performance to crap, reverting it made everything fast again.
recv manpage says there is three ways to get zero returned
1) When a stream socket peer has performed an orderly shutdown, the return value will be 0 (the traditional "end-of-file"
return).
2) Datagram sockets in various domains (e.g., the UNIX and Internet domains) permit zero-length datagrams. When such a
datagram is received, the return value is 0.
3) The value 0 may also be returned if the requested number of bytes to receive from a stream socket was 0.
we can't just assume it means the peer shut down.
If the peer shut down, then the event loop should get an event on the socket like POLLHUP and deal with it that way.
So the patch mentioned above is simply reverted here.
Signed-off-by: Andy Green <andy@warmcat.com>
---
lib/output.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/lib/output.c b/lib/output.c
index 11f88e82..0d850ebe 100644
--- a/lib/output.c
+++ b/lib/output.c
@@ -622,7 +622,7 @@ lws_ssl_capable_read_no_ssl(struct lws *wsi, unsigned char *buf, int len)
int n;
n = recv(wsi->sock, (char *)buf, len, 0);
- if (n > 0)
+ if (n >= 0)
return n;
#if LWS_POSIX
if (LWS_ERRNO == LWS_EAGAIN ||
--
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