commit d79cbf15e6ba119767d2a035047ff67c19465961
author Vladimir Homutov <vl@nginx.com> Mon Sep 01 17:55:07 2014 +0400
committer Vladimir Homutov <vl@nginx.com> Mon Sep 01 17:55:07 2014 +0400
tree 9e363552e99868e815615f9ae419c65f42a632c1
parent bba2ce8aae96cfc81fa338dde1675397dd3bed4c

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.

src/core/ngx_syslog.c

diff --git a/src/core/ngx_syslog.c b/src/core/ngx_syslog.c
index e6d40f4..2555f29 100644
--- a/src/core/ngx_syslog.c
+++ b/src/core/ngx_syslog.c
@@ -234,11 +234,11 @@
 
     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 @@
 
     (void) ngx_syslog_send(peer, msg, p - msg);
 
-    peer->processing = 0;
+    peer->busy = 0;
 }
 
 
@@ -267,6 +267,9 @@
         }
     }
 
+    /* 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 @@
 
     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_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");

src/core/ngx_syslog.h

diff --git a/src/core/ngx_syslog.h b/src/core/ngx_syslog.h
index 92d47d5..a915051 100644
--- a/src/core/ngx_syslog.h
+++ b/src/core/ngx_syslog.h
@@ -16,7 +16,7 @@
 
     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;