transmission/libtransmission/trevent.c

305 lines
6.7 KiB
C

/*
* This file Copyright (C) 2007-2008 Charles Kerr <charles@rebelbase.com>
*
* This file is licensed by the GPL version 2. Works owned by the
* Transmission project are granted a special exemption to clause 2(b)
* so that the bulk of its code can remain under the MIT license.
* This exemption does not extend to derived works not owned by
* the Transmission project.
*
* $Id$
*/
#include <assert.h>
#include <errno.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <signal.h>
#ifdef WIN32
#include <fcntl.h>
#define pipe( f ) _pipe( f, 1000, _O_BINARY )
#else
#include <unistd.h>
#endif
#include <event.h>
#include "transmission.h"
#include "platform.h"
#include "trevent.h"
#include "utils.h"
/***
****
***/
typedef struct tr_event_handle
{
uint8_t die;
int fds[2];
tr_lock * lock;
tr_handle * h;
tr_thread * thread;
struct event_base * base;
struct event pipeEvent;
}
tr_event_handle;
typedef int timer_func ( void* );
struct tr_timer
{
struct event event;
struct timeval tv;
timer_func * func;
void * user_data;
struct tr_event_handle * eh;
uint8_t inCallback;
};
struct tr_run_data
{
void ( *func )( void * );
void * user_data;
};
#define dbgmsg( fmt... ) tr_deepLog( __FILE__, __LINE__, "event", ## fmt )
static void
readFromPipe( int fd,
short eventType,
void * veh )
{
char ch;
int ret;
tr_event_handle * eh = veh;
dbgmsg( "readFromPipe: eventType is %hd", eventType );
/* read the command type */
ch = '\0';
do
{
ret = read( fd, &ch, 1 );
}
while( !eh->die && ret < 0 && errno == EAGAIN );
dbgmsg( "command is [%c], ret is %d, errno is %d", ch, ret, (int)errno );
switch( ch )
{
case 'r': /* run in libevent thread */
{
struct tr_run_data data;
const size_t nwant = sizeof( data );
const ssize_t ngot = read( fd, &data, nwant );
if( !eh->die && ( ngot == (ssize_t)nwant ) )
{
dbgmsg( "invoking function in libevent thread" );
( data.func )( data.user_data );
}
break;
}
case 't': /* create timer */
{
tr_timer * timer;
const size_t nwant = sizeof( timer );
const ssize_t ngot = read( fd, &timer, nwant );
if( !eh->die && ( ngot == (ssize_t)nwant ) )
{
dbgmsg( "adding timer in libevent thread" );
evtimer_add( &timer->event, &timer->tv );
}
break;
}
case '\0': /* eof */
{
dbgmsg( "pipe eof reached... removing event listener" );
event_del( &eh->pipeEvent );
break;
}
default:
{
assert( 0 && "unhandled command type!" );
break;
}
}
}
static void
logFunc( int severity,
const char * message )
{
if( severity >= _EVENT_LOG_ERR )
tr_nerr( "%s", message );
else
tr_ndbg( "%s", message );
}
static void
libeventThreadFunc( void * veh )
{
tr_event_handle * eh = (tr_event_handle *) veh;
tr_dbg( "Starting libevent thread" );
#ifndef WIN32
/* Don't exit when writing on a broken socket */
signal( SIGPIPE, SIG_IGN );
#endif
eh->base = event_init( );
eh->h->events = eh;
event_set_log_callback( logFunc );
/* listen to the pipe's read fd */
event_set( &eh->pipeEvent, eh->fds[0], EV_READ | EV_PERSIST,
readFromPipe,
veh );
event_add( &eh->pipeEvent, NULL );
event_dispatch( );
tr_lockFree( eh->lock );
event_base_free( eh->base );
eh->h->events = NULL;
tr_free( eh );
tr_dbg( "Closing libevent thread" );
}
void
tr_eventInit( tr_handle * handle )
{
tr_event_handle * eh;
eh = tr_new0( tr_event_handle, 1 );
eh->lock = tr_lockNew( );
pipe( eh->fds );
eh->h = handle;
eh->thread = tr_threadNew( libeventThreadFunc, eh );
}
void
tr_eventClose( tr_handle * handle )
{
handle->events->die = TRUE;
tr_deepLog( __FILE__, __LINE__, NULL, "closing trevent pipe" );
close( handle->events->fds[1] );
}
/**
***
**/
int
tr_amInEventThread( struct tr_handle * handle )
{
return tr_amInThread( handle->events->thread );
}
/**
***
**/
static void
timerCallback( int fd UNUSED,
short event UNUSED,
void * vtimer )
{
int more;
struct tr_timer * timer = vtimer;
timer->inCallback = 1;
more = ( *timer->func )( timer->user_data );
timer->inCallback = 0;
if( more )
evtimer_add( &timer->event, &timer->tv );
else
tr_timerFree( &timer );
}
void
tr_timerFree( tr_timer ** ptimer )
{
tr_timer * timer;
/* zero out the argument passed in */
assert( ptimer );
timer = *ptimer;
*ptimer = NULL;
/* destroy the timer directly or via the command queue */
if( timer && !timer->inCallback )
{
assert( tr_amInEventThread( timer->eh->h ) );
event_del( &timer->event );
tr_free( timer );
}
}
tr_timer*
tr_timerNew( struct tr_handle * handle,
timer_func func,
void * user_data,
uint64_t interval_milliseconds )
{
tr_timer * timer = tr_new0( tr_timer, 1 );
timer->tv = tr_timevalMsec( interval_milliseconds );
timer->func = func;
timer->user_data = user_data;
timer->eh = handle->events;
evtimer_set( &timer->event, timerCallback, timer );
if( tr_amInThread( handle->events->thread ) )
{
evtimer_add( &timer->event, &timer->tv );
}
else
{
const char ch = 't';
int fd = handle->events->fds[1];
tr_lock * lock = handle->events->lock;
tr_lockLock( lock );
write( fd, &ch, 1 );
write( fd, &timer, sizeof( timer ) );
tr_lockUnlock( lock );
}
return timer;
}
void
tr_runInEventThread( struct tr_handle * handle,
void func( void* ),
void * user_data )
{
if( tr_amInThread( handle->events->thread ) )
{
(func)( user_data );
}
else
{
const char ch = 'r';
int fd = handle->events->fds[1];
tr_lock * lock = handle->events->lock;
struct tr_run_data data;
tr_lockLock( lock );
write( fd, &ch, 1 );
data.func = func;
data.user_data = user_data;
write( fd, &data, sizeof( data ) );
tr_lockUnlock( lock );
}
}