[PATCH] chg: just take it as EOF if recv() returns 0

[Jun Wu]

Yes, please.

Excerpts from Yuya Nishihara's message of 2016-08-06 13:51:39 +0900:
> # HG changeset patch
> # User Yuya Nishihara <yuya at tcha.org>
> # Date 1470399693 -32400
> #      Fri Aug 05 21:21:33 2016 +0900
> # Node ID e59b4315a3f8602582f0d39e1c531faaa3119982
> # Parent  56e9357be6b2704678331999e8b4b02777fc724b
> chg: just take it as EOF if recv() returns 0
> 
> hgc->sockfd is a blocking stream socket. recv() should never return 0 other
> than EOF.
> 
> See 4fc4b8cc9957 for the original problem.
> 
> diff --git a/contrib/chg/hgclient.c b/contrib/chg/hgclient.c
> --- a/contrib/chg/hgclient.c
> +++ b/contrib/chg/hgclient.c
> @@ -126,15 +126,10 @@ static void readchannel(hgclient_t *hgc)
>          return;  /* assumes input request */
>  
>      size_t cursize = 0;
> -    int emptycount = 0;
>      while (cursize < hgc->ctx.datasize) {
>          rsize = recv(hgc->sockfd, hgc->ctx.data + cursize,
>                   hgc->ctx.datasize - cursize, 0);
> -        /* rsize == 0 normally indicates EOF, while it's also a valid
> -         * packet size for unix socket. treat it as EOF and abort if
> -         * we get many empty responses in a row. */
> -        emptycount = (rsize == 0 ? emptycount + 1 : 0);
> -        if (rsize < 0 || emptycount > 20)
> +        if (rsize < 1)
>              abortmsg("failed to read data block");
>          cursize += rsize;
>      }