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/*++
/* NAME
/* pass_trigger 3
/* SUMMARY
/* trigger file descriptor listener
/* SYNOPSIS
/* #include <trigger.h>
/*
/* int pass_trigger(service, buf, len, timeout)
/* const char *service;
/* const char *buf;
/* ssize_t len;
/* int timeout;
/* DESCRIPTION
/* pass_trigger() connects to the named local server by sending
/* a file descriptor 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), local client
/* stream_connect(3), streams-based 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 pass_trigger {
int connect_fd;
char *service;
int pass_fd[2];
};
/* pass_trigger_event - disconnect from peer */
static void pass_trigger_event(int event, void *context)
{
struct pass_trigger *pp = (struct pass_trigger *) context;
static const char *myname = "pass_trigger_event";
/*
* Disconnect.
*/
if (event == EVENT_TIME)
msg_warn("%s: read timeout for service %s", myname, pp->service);
event_disable_readwrite(pp->connect_fd);
event_cancel_timer(pass_trigger_event, context);
/* Don't combine multiple close() calls into one boolean expression. */
if (close(pp->connect_fd) < 0)
msg_warn("%s: close %s: %m", myname, pp->service);
if (close(pp->pass_fd[0]) < 0)
msg_warn("%s: close pipe: %m", myname);
if (close(pp->pass_fd[1]) < 0)
msg_warn("%s: close pipe: %m", myname);
myfree(pp->service);
myfree((void *) pp);
}
/* pass_trigger - wakeup local server */
int pass_trigger(const char *service, const char *buf, ssize_t len, int timeout)
{
const char *myname = "pass_trigger";
int pass_fd[2];
struct pass_trigger *pp;
int connect_fd;
if (msg_verbose > 1)
msg_info("%s: service %s", myname, service);
/*
* Connect...
*/
if ((connect_fd = LOCAL_CONNECT(service, BLOCKING, timeout)) < 0) {
if (msg_verbose)
msg_warn("%s: connect to %s: %m", myname, service);
return (-1);
}
close_on_exec(connect_fd, CLOSE_ON_EXEC);
/*
* Create a pipe, and send one pipe end to the server.
*/
if (pipe(pass_fd) < 0)
msg_fatal("%s: pipe: %m", myname);
close_on_exec(pass_fd[0], CLOSE_ON_EXEC);
close_on_exec(pass_fd[1], CLOSE_ON_EXEC);
if (LOCAL_SEND_FD(connect_fd, pass_fd[0]) < 0)
msg_fatal("%s: send file descriptor: %m", myname);
/*
* Stash away context.
*/
pp = (struct pass_trigger *) mymalloc(sizeof(*pp));
pp->connect_fd = connect_fd;
pp->service = mystrdup(service);
pp->pass_fd[0] = pass_fd[0];
pp->pass_fd[1] = pass_fd[1];
/*
* Write the request...
*/
if (write_buf(pass_fd[1], buf, len, timeout) < 0
|| write_buf(pass_fd[1], "", 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(pass_trigger_event, (void *) pp, timeout + 100);
event_enable_read(connect_fd, pass_trigger_event, (void *) pp);
return (0);
}
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