1 files changed, 119 insertions, 0 deletions
diff --git a/src/lib-old-stats/stats-connection.c b/src/lib-old-stats/stats-connection.c
new file mode 100644
index 0000000..24b5e73
--- /dev/null
+++ b/src/lib-old-stats/stats-connection.c
@@ -0,0 +1,119 @@
+/* Copyright (c) 2011-2018 Dovecot authors, see the included COPYING file */
+
+#include "lib.h"
+#include "ioloop.h"
+#include "str.h"
+#include "master-service.h"
+#include "stats-connection.h"
+
+#include <unistd.h>
+#include <fcntl.h>
+
+#define STATS_EAGAIN_WARN_INTERVAL_SECS 30
+
+struct stats_connection {
+	int refcount;
+
+	int fd;
+	char *path;
+
+	bool open_failed;
+	time_t next_warning_timestamp;
+};
+
+static bool stats_connection_open(struct stats_connection *conn)
+{
+	if (conn->open_failed)
+		return FALSE;
+
+	conn->fd = open(conn->path, O_WRONLY | O_NONBLOCK);
+	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)
+{
+	struct stats_connection *conn;
+
+	conn = i_new(struct stats_connection, 1);
+	conn->refcount = 1;
+	conn->path = i_strdup(path);
+	(void)stats_connection_open(conn);
+	return conn;
+}
+
+void stats_connection_ref(struct stats_connection *conn)
+{
+	conn->refcount++;
+}
+
+void stats_connection_unref(struct stats_connection **_conn)
+{
+	struct stats_connection *conn = *_conn;
+
+	i_assert(conn->refcount > 0);
+	if (--conn->refcount > 0)
+		return;
+
+	*_conn = NULL;
+	i_close_fd_path(&conn->fd, conn->path);
+	i_free(conn->path);
+	i_free(conn);
+}
+
+int stats_connection_send(struct stats_connection *conn, const string_t *str)
+{
+	static bool pipe_warned = FALSE;
+	ssize_t ret;
+
+	/* if master process has been stopped (and restarted), don't even try
+	   to notify the stats process anymore. even if one exists, it doesn't
+	   know about us. */
+	if (master_service_is_master_stopped(master_service))
+		return -1;
+
+	if (conn->fd == -1) {
+		if (!stats_connection_open(conn))
+			return -1;
+		i_assert(conn->fd != -1);
+	}
+
+	if (str_len(str) > PIPE_BUF && !pipe_warned) {
+		i_warning("stats update sent more bytes that PIPE_BUF "
+			  "(%zu > %u), this may break statistics",
+			  str_len(str), (unsigned int)PIPE_BUF);
+		pipe_warned = TRUE;
+	}
+
+	ret = write(conn->fd, str_data(str), str_len(str));
+	if (ret == (ssize_t)str_len(str)) {
+		/* success */
+		return 0;
+	} else if (ret < 0 && errno == EAGAIN) {
+		/* stats process is busy */
+		if (ioloop_time > conn->next_warning_timestamp) {
+			i_warning("write(%s) failed: %m (stats process is busy)", conn->path);
+			conn->next_warning_timestamp = ioloop_time +
+				STATS_EAGAIN_WARN_INTERVAL_SECS;
+		}
+		return -1;
+	} else {
+		/* error - reconnect */
+		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);
+		if (close(conn->fd) < 0)
+			i_error("close(%s) failed: %m", conn->path);
+		conn->fd = -1;
+		return -1;
+	}
+}