1 files changed, 131 insertions, 0 deletions
diff --git a/src/util/unix_trigger.c b/src/util/unix_trigger.c
new file mode 100644
index 0000000..59a18ff
--- /dev/null
+++ b/src/util/unix_trigger.c
@@ -0,0 +1,131 @@
+/*++
+/* NAME
+/*	unix_trigger 3
+/* SUMMARY
+/*	wakeup UNIX-domain server
+/* SYNOPSIS
+/*	#include <trigger.h>
+/*
+/*	int	unix_trigger(service, buf, len, timeout)
+/*	const char *service;
+/*	const char *buf;
+/*	ssize_t	len;
+/*	int	timeout;
+/* DESCRIPTION
+/*	unix_trigger() wakes up the named UNIX-domain server by making
+/*	a brief connection to it and writing the named buffer.
+/*
+/*	The connection is closed by a background thread. Some kernels
+/*	cannot handle client-side disconnect before the server has
+/*	received the message.
+/*
+/*	Arguments:
+/* .IP service
+/*	Name of the communication endpoint.
+/* .IP buf
+/*	Address of data to be written.
+/* .IP len
+/*	Amount of data to be written.
+/* .IP timeout
+/*	Deadline in seconds. Specify a value <= 0 to disable
+/*	the time limit.
+/* DIAGNOSTICS
+/*	The result is zero in case of success, -1 in case of problems.
+/* SEE ALSO
+/*	unix_connect(3), UNIX-domain client
+/* LICENSE
+/* .ad
+/* .fi
+/*	The Secure Mailer license must be distributed with this software.
+/* AUTHOR(S)
+/*	Wietse Venema
+/*	IBM T.J. Watson Research
+/*	P.O. Box 704
+/*	Yorktown Heights, NY 10598, USA
+/*--*/
+
+/* System library. */
+
+#include <sys_defs.h>
+#include <sys/socket.h>
+#include <unistd.h>
+#include <string.h>
+
+/* Utility library. */
+
+#include <msg.h>
+#include <connect.h>
+#include <iostuff.h>
+#include <mymalloc.h>
+#include <events.h>
+#include <trigger.h>
+
+struct unix_trigger {
+    int     fd;
+    char   *service;
+};
+
+/* unix_trigger_event - disconnect from peer */
+
+static void unix_trigger_event(int event, void *context)
+{
+    struct unix_trigger *up = (struct unix_trigger *) context;
+    static const char *myname = "unix_trigger_event";
+
+    /*
+     * Disconnect.
+     */
+    if (event == EVENT_TIME)
+	msg_warn("%s: read timeout for service %s", myname, up->service);
+    event_disable_readwrite(up->fd);
+    event_cancel_timer(unix_trigger_event, context);
+    if (close(up->fd) < 0)
+	msg_warn("%s: close %s: %m", myname, up->service);
+    myfree(up->service);
+    myfree((void *) up);
+}
+
+/* unix_trigger - wakeup UNIX-domain server */
+
+int     unix_trigger(const char *service, const char *buf, ssize_t len, int timeout)
+{
+    const char *myname = "unix_trigger";
+    struct unix_trigger *up;
+    int     fd;
+
+    if (msg_verbose > 1)
+	msg_info("%s: service %s", myname, service);
+
+    /*
+     * Connect...
+     */
+    if ((fd = unix_connect(service, BLOCKING, timeout)) < 0) {
+	if (msg_verbose)
+	    msg_warn("%s: connect to %s: %m", myname, service);
+	return (-1);
+    }
+    close_on_exec(fd, CLOSE_ON_EXEC);
+
+    /*
+     * Stash away context.
+     */
+    up = (struct unix_trigger *) mymalloc(sizeof(*up));
+    up->fd = fd;
+    up->service = mystrdup(service);
+
+    /*
+     * Write the request...
+     */
+    if (write_buf(fd, buf, len, timeout) < 0
+	|| write_buf(fd, "", 1, timeout) < 0)
+	if (msg_verbose)
+	    msg_warn("%s: write to %s: %m", myname, service);
+
+    /*
+     * Wakeup when the peer disconnects, or when we lose patience.
+     */
+    if (timeout > 0)
+	event_request_timer(unix_trigger_event, (void *) up, timeout + 100);
+    event_enable_read(fd, unix_trigger_event, (void *) up);
+    return (0);
+}