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/*
* %CopyrightBegin%
*
* Copyright Ericsson AB 1997-2009. All Rights Reserved.
*
* The contents of this file are subject to the Erlang Public License,
* Version 1.1, (the "License"); you may not use this file except in
* compliance with the License. You should have received a copy of the
* Erlang Public License along with this software. If not, it can be
* retrieved online at http://www.erlang.org/.
*
* Software distributed under the License is distributed on an "AS IS"
* basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
* the License for the specific language governing rights and limitations
* under the License.
*
* %CopyrightEnd%
*/
/* timeout.c
*
* todo: use posix timers (timer_create etc) instead of setitimer.
*
*/
#if !defined(__WIN32__) && !defined(VXWORKS)
/* FIXME: well, at least I can compile now... */
#include "eidef.h"
#include <stdio.h>
#include <stdlib.h>
#include <setjmp.h>
#include <signal.h>
#if TIME_WITH_SYS_TIME
# include <sys/time.h>
# include <time.h>
#else
# if HAVE_SYS_TIME_H
# include <sys/time.h>
# else
# include <time.h>
# endif
#endif
#include "erl_timeout.h"
typedef struct jmp_s {
jmp_buf jmpbuf;
struct itimerval timerinfo;
void *siginfo;
struct jmp_s *next;
} *jmp_t;
static jmp_t push(jmp_t j);
static jmp_t pop(void);
static void timeout_handler(int dummy);
jmp_buf *timeout_setup(int ms)
{
struct itimerval t;
jmp_t j;
void *s;
#ifdef DEBUG
fprintf(stderr,"timeout setup\n");
#endif
s=signal(SIGALRM,timeout_handler);
/* set the timer */
t.it_interval.tv_sec = 0;
t.it_interval.tv_usec = 0;
t.it_value.tv_sec = ms / 1000;
t.it_value.tv_usec = (ms % 1000) * 1000;
/* get a jump buffer and save it */
j = malloc(sizeof(*j)); /* FIXME check result */
j->siginfo = s;
push(j);
setitimer(ITIMER_REAL,&t,&(j->timerinfo));
return &(j->jmpbuf);
}
int timeout_cancel(void)
{
jmp_t j;
#ifdef DEBUG
fprintf(stderr,"timeout cancel\n");
#endif
/* retrieve the jump buffer */
j=pop();
/* restore the timer and signal disposition */
setitimer(ITIMER_REAL,&(j->timerinfo),NULL);
signal(SIGALRM,j->siginfo);
free(j);
return 0;
}
void timeout_handler(int dummy)
{
jmp_t j;
#ifdef DEBUG
fprintf(stderr,"timeout handler\n");
#endif
/* retrieve the jump buffer */
j=pop();
/* restore the timer and signal disposition */
setitimer(ITIMER_REAL,&(j->timerinfo),NULL);
signal(SIGALRM,j->siginfo);
free(j);
longjmp(j->jmpbuf,JMPVAL);
return; /* not reached */
}
/* a simple stack for saving the jump buffer allows us to pass a
* variable between functions that don't call each other, in a way
* that will survive the longjmp().
*/
/* FIXME problem for threaded ? */
static jmp_t jmp_head=NULL;
#ifdef DEBUG
static int depth = 0;
static int maxdepth = 0;
#endif
static jmp_t push(jmp_t j)
{
j->next = jmp_head;
jmp_head = j;
#ifdef DEBUG
depth++;
if (depth > maxdepth) maxdepth = depth;
#endif
return j;
}
static jmp_t pop(void)
{
jmp_t j = jmp_head;
if (j) jmp_head = j->next;
#ifdef DEBUG
depth--;
#endif
return j;
}
#endif /* platform */
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