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-rw-r--r--src/util/stream_trigger.c130
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diff --git a/src/util/stream_trigger.c b/src/util/stream_trigger.c
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+/*++
+/* NAME
+/* stream_trigger 3
+/* SUMMARY
+/* wakeup stream server
+/* SYNOPSIS
+/* #include <trigger.h>
+/*
+/* int stream_trigger(service, buf, len, timeout)
+/* const char *service;
+/* const char *buf;
+/* ssize_t len;
+/* int timeout;
+/* DESCRIPTION
+/* stream_trigger() wakes up the named stream 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
+/* stream_connect(3), stream 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 <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 stream_trigger {
+ int fd;
+ char *service;
+};
+
+/* stream_trigger_event - disconnect from peer */
+
+static void stream_trigger_event(int event, void *context)
+{
+ struct stream_trigger *sp = (struct stream_trigger *) context;
+ static const char *myname = "stream_trigger_event";
+
+ /*
+ * Disconnect.
+ */
+ if (event == EVENT_TIME)
+ msg_warn("%s: read timeout for service %s", myname, sp->service);
+ event_disable_readwrite(sp->fd);
+ event_cancel_timer(stream_trigger_event, context);
+ if (close(sp->fd) < 0)
+ msg_warn("%s: close %s: %m", myname, sp->service);
+ myfree(sp->service);
+ myfree((void *) sp);
+}
+
+/* stream_trigger - wakeup stream server */
+
+int stream_trigger(const char *service, const char *buf, ssize_t len, int timeout)
+{
+ const char *myname = "stream_trigger";
+ struct stream_trigger *sp;
+ int fd;
+
+ if (msg_verbose > 1)
+ msg_info("%s: service %s", myname, service);
+
+ /*
+ * Connect...
+ */
+ if ((fd = stream_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.
+ */
+ sp = (struct stream_trigger *) mymalloc(sizeof(*sp));
+ sp->fd = fd;
+ sp->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(stream_trigger_event, (void *) sp, timeout + 100);
+ event_enable_read(fd, stream_trigger_event, (void *) sp);
+ return (0);
+}