Upstream: fixed timeouts with gRPC, SSL and select (ticket #2229). With SSL it is possible that an established connection is ready for reading after the handshake. Further, events might be already disabled in case of level-triggered event methods. If this happens and ngx_http_upstream_send_request() blocks waiting for some data from the upstream, such as flow control in case of gRPC, the connection will time out due to no read events on the upstream connection. Fix is to explicitly check the c->read->ready flag if sending request blocks and post a read event if it is set. Note that while it is possible to modify ngx_ssl_handshake() to keep read events active, this won't completely resolve the issue, since there can be data already received during the SSL handshake (see 573bd30e46b4).

/*
 * Copyright (C) Nginx, Inc.
 */


#ifndef _NGX_SYSLOG_H_INCLUDED_
#define _NGX_SYSLOG_H_INCLUDED_


typedef struct {
    ngx_uint_t        facility;
    ngx_uint_t        severity;
    ngx_str_t         tag;

    ngx_addr_t        server;
    ngx_connection_t  conn;
    unsigned          busy:1;
    unsigned          nohostname:1;
} ngx_syslog_peer_t;


char *ngx_syslog_process_conf(ngx_conf_t *cf, ngx_syslog_peer_t *peer);
u_char *ngx_syslog_add_header(ngx_syslog_peer_t *peer, u_char *buf);
void ngx_syslog_writer(ngx_log_t *log, ngx_uint_t level, u_char *buf,
    size_t len);
ssize_t ngx_syslog_send(ngx_syslog_peer_t *peer, u_char *buf, size_t len);


#endif /* _NGX_SYSLOG_H_INCLUDED_ */