stats: Don't log write()=EPIPE failures. Retry opening the pipe once.

diff --git a/src/plugins/stats/stats-connection.c b/src/plugins/stats/stats-connection.c
index a62600d218de8c1a768addd0f24f1775cb6aeed2..38f2ec88513b2c9490328643bb6f6b5956881a53 100644 (file)
--- a/src/plugins/stats/stats-connection.c
+++ b/src/plugins/stats/stats-connection.c
@@ -14,8 +14,24 @@ struct stats_connection {
 
        int fd;
        char *path;
+
+       bool open_failed;
 };
 
+static bool stats_connection_open(struct stats_connection *conn)
+{
+       if (conn->open_failed)
+               return FALSE;
+
+       conn->fd = open(conn->path, O_WRONLY);
+       if (conn->fd == -1) {
+               i_error("stats: open(%s) failed: %m", conn->path);
+               conn->open_failed = TRUE;
+               return FALSE;
+       }
+       return TRUE;
+}
+
 struct stats_connection *
 stats_connection_create(const char *path)
 {
@@ -24,9 +40,7 @@ stats_connection_create(const char *path)
        conn = i_new(struct stats_connection, 1);
        conn->refcount = 1;
        conn->path = i_strdup(path);
-       conn->fd = open(path, O_WRONLY);
-       if (conn->fd == -1)
-               i_error("stats: open(%s) failed: %m", path);
+       stats_connection_open(conn);
        return conn;
 }
 
@@ -57,8 +71,10 @@ void stats_connection_send(struct stats_connection *conn, const string_t *str)
        static bool pipe_warned = FALSE;
        ssize_t ret;
 
-       if (conn->fd == -1)
-               return;
+       if (conn->fd == -1) {
+               if (!stats_connection_open(conn))
+                       return;
+       }
 
        if (str_len(str) > PIPE_BUF && !pipe_warned) {
                i_warning("stats update sent more bytes that PIPE_BUF "
@@ -69,11 +85,13 @@ void stats_connection_send(struct stats_connection *conn, const string_t *str)
 
        ret = write(conn->fd, str_data(str), str_len(str));
        if (ret != (ssize_t)str_len(str)) {
-               if (ret < 0)
-                       i_error("write(%s) failed: %m", conn->path);
-               else if ((size_t)ret != str_len(str))
+               if (ret < 0) {
+                       /* don't log EPIPE errors. they can happen when
+                          Dovecot is stopped. */
+                       if (errno != EPIPE)
+                               i_error("write(%s) failed: %m", conn->path);
+               } else if ((size_t)ret != str_len(str))
                        i_error("write(%s) wrote partial update", conn->path);
-               /* this shouldn't happen, just stop sending updates */
                if (close(conn->fd) < 0)
                        i_error("close(%s) failed: %m", conn->path);
                conn->fd = -1;