# HG changeset patch
# User Vladimir Homutov <vl@nginx.com>
# Date 1409579707 -14400
# Node ID 2cb5275bf5e73af5d0d905c4dfc54e99d2581a21
# Parent  1b8459a53e4bbd8a43402cbbf20b17524a0f056b
Syslog: enabled logging of send errors.

The ngx_cycle->log is used when sending the message.  This allows to log syslog
send errors in another log.

Logging to syslog after its cleanup handler has been executed was prohibited.
Previously, this was possible from ngx_destroy_pool(), which resulted in error
messages caused by attempts to write into the closed socket.

The "processing" flag is renamed to "busy" to better match its semantics.

diff --git a/src/core/ngx_syslog.c b/src/core/ngx_syslog.c
--- a/src/core/ngx_syslog.c
+++ b/src/core/ngx_syslog.c
@@ -234,11 +234,11 @@ ngx_syslog_writer(ngx_log_t *log, ngx_ui
 
     peer = log->wdata;
 
-    if (peer->processing) {
+    if (peer->busy) {
         return;
     }
 
-    peer->processing = 1;
+    peer->busy = 1;
     peer->severity = level - 1;
 
     p = ngx_syslog_add_header(peer, msg);
@@ -254,7 +254,7 @@ ngx_syslog_writer(ngx_log_t *log, ngx_ui
 
     (void) ngx_syslog_send(peer, msg, p - msg);
 
-    peer->processing = 0;
+    peer->busy = 0;
 }
 
 
@@ -267,6 +267,9 @@ ngx_syslog_send(ngx_syslog_peer_t *peer,
         }
     }
 
+    /* log syslog socket events with valid log */
+    peer->conn.log = ngx_cycle->log;
+
     if (ngx_send) {
         return ngx_send(&peer->conn, buf, len);
 
@@ -285,7 +288,6 @@ ngx_syslog_init_peer(ngx_syslog_peer_t *
 
     peer->conn.read = &ngx_syslog_dummy_event;
     peer->conn.write = &ngx_syslog_dummy_event;
-    peer->conn.log = &ngx_syslog_dummy_log;
 
     ngx_syslog_dummy_event.log = &ngx_syslog_dummy_log;
 
@@ -339,6 +341,9 @@ ngx_syslog_cleanup(void *data)
 {
     ngx_syslog_peer_t  *peer = data;
 
+    /* prevents further use of this peer */
+    peer->busy = 1;
+
     if (ngx_close_socket(peer->conn.fd) == -1) {
         ngx_log_error(NGX_LOG_ALERT, ngx_cycle->log, ngx_socket_errno,
                       ngx_close_socket_n " failed");
diff --git a/src/core/ngx_syslog.h b/src/core/ngx_syslog.h
--- a/src/core/ngx_syslog.h
+++ b/src/core/ngx_syslog.h
@@ -16,7 +16,7 @@ typedef struct {
 
     ngx_addr_t        server;
     ngx_connection_t  conn;
-    ngx_uint_t        processing;  /* unsigned processing:1; */
+    ngx_uint_t        busy;  /* unsigned busy:1; */
 } ngx_syslog_peer_t;