Unverified Commit 47e540df authored by Daniel Stenberg's avatar Daniel Stenberg
Browse files

examples: remove recursive calls to curl_multi_socket_action 

From within the timer callbacks. Recursive is problematic for several
reasons. They should still work, but this way the examples and the
documentation becomes simpler. I don't think we need to encourage
recursive calls.

Discussed in #3537
Closes #3601
parent 42b30ee8

docs/examples/evhiperfifo.c

+3 −4
Original line number Diff line number Diff line
@@ -5,7 +5,7 @@ 
 *                            | (__| |_| |  _ <| |___

 *                             \___|\___/|_| \_\_____|

 *

 * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.

 * Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@haxx.se>, et al.

 *

 * This software is licensed as described in the file COPYING, which

 * you should have received as part of this distribution. The terms
@@ -119,13 +119,12 @@ static int multi_timer_cb(CURLM *multi, long timeout_ms, GlobalInfo *g) 
{

  DPRINT("%s %li\n", __PRETTY_FUNCTION__,  timeout_ms);

  ev_timer_stop(g->loop, &g->timer_event);

  if(timeout_ms > 0) {

  if(timeout_ms >= 0) {

    /* -1 means delete, other values are timeout times in milliseconds */

    double  t = timeout_ms / 1000;

    ev_timer_init(&g->timer_event, timer_cb, t, 0.);

    ev_timer_start(g->loop, &g->timer_event);

  }

  else if(timeout_ms == 0)

    timer_cb(g->loop, &g->timer_event, 0);

  return 0;

}

docs/examples/ghiper.c

+6 −8
Original line number Diff line number Diff line
@@ -5,7 +5,7 @@ 
 *                            | (__| |_| |  _ <| |___

 *                             \___|\___/|_| \_\_____|

 *

 * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.

 * Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@haxx.se>, et al.

 *

 * This software is licensed as described in the file COPYING, which

 * you should have received as part of this distribution. The terms
@@ -163,15 +163,13 @@ static int update_timeout_cb(CURLM *multi, long timeout_ms, void *userp) 
  MSG_OUT("*** update_timeout_cb %ld => %ld:%ld ***\n",

          timeout_ms, timeout.tv_sec, timeout.tv_usec);



  /* TODO

   *

   * if timeout_ms is 0, call curl_multi_socket_action() at once!

   *

  /*

   * if timeout_ms is -1, just delete the timer

   *

   * for all other values of timeout_ms, this should set or *update*

   * the timer to the new value

   * For other values of timeout_ms, this should set or *update* the timer to

   * the new value

   */

  if(timeout_ms >= 0)

    g->timer_event = g_timeout_add(timeout_ms, timer_cb, g);

  return 0;

}

docs/examples/hiperfifo.c

+6 −14
Original line number Diff line number Diff line
@@ -5,7 +5,7 @@ 
 *                            | (__| |_| |  _ <| |___

 *                             \___|\___/|_| \_\_____|

 *

 * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.

 * Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@haxx.se>, et al.

 *

 * This software is licensed as described in the file COPYING, which

 * you should have received as part of this distribution. The terms
@@ -152,23 +152,15 @@ static int multi_timer_cb(CURLM *multi _Unused, long timeout_ms, GlobalInfo *g) 
  timeout.tv_usec = (timeout_ms%1000)*1000;

  fprintf(MSG_OUT, "multi_timer_cb: Setting timeout to %ld ms\n", timeout_ms);



  /* TODO

   *

   * if timeout_ms is 0, call curl_multi_socket_action() at once!

   *

  /*

   * if timeout_ms is -1, just delete the timer

   *

   * for all other values of timeout_ms, this should set or *update*

   * the timer to the new value

   * For all other values of timeout_ms, this should set or *update* the timer

   * to the new value

   */

  if(timeout_ms == 0) {

    rc = curl_multi_socket_action(g->multi,

                                  CURL_SOCKET_TIMEOUT, 0, &g->still_running);

    mcode_or_die("multi_timer_cb: curl_multi_socket_action", rc);

  }

  else if(timeout_ms == -1)

  if(timeout_ms == -1)

    evtimer_del(&g->timer_event);

  else

  else /* includes timeout zero */

    evtimer_add(&g->timer_event, &timeout);

  return 0;

}

docs/libcurl/opts/CURLMOPT_TIMERFUNCTION.3

+7 −9
Original line number Diff line number Diff line
@@ -5,7 +5,7 @@ 
.\" *                            | (__| |_| |  _ <| |___

.\" *                             \___|\___/|_| \_\_____|

.\" *

.\" * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.

.\" * Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@haxx.se>, et al.

.\" *

.\" * This software is licensed as described in the file COPYING, which

.\" * you should have received as part of this distribution. The terms
@@ -28,7 +28,7 @@ CURLMOPT_TIMERFUNCTION \- set callback to receive timeout values 
#include <curl/curl.h>



int timer_callback(CURLM *multi,    /* multi handle */

                   long timeout_ms, /* see above */

                   long timeout_ms, /* timeout in number of ms */

                   void *userp);    /* private callback pointer */



CURLMcode curl_multi_setopt(CURLM *handle, CURLMOPT_TIMERFUNCTION, timer_callback);
@@ -40,17 +40,15 @@ Certain features, such as timeouts and retries, require you to call libcurl 
even when there is no activity on the file descriptors.



Your callback function \fBtimer_callback\fP should install a non-repeating

timer with an interval of \fBtimeout_ms\fP. Each time that timer fires, call

timer with an interval of \fBtimeout_ms\fP. When time that timer fires, call

either \fIcurl_multi_socket_action(3)\fP or \fIcurl_multi_perform(3)\fP,

depending on which interface you use.



A \fBtimeout_ms\fP value of -1 means you should delete your timer.

A \fBtimeout_ms\fP value of -1 passed to this callback means you should delete

the timer. All other values are valid expire times in number of milliseconds.



A \fBtimeout_ms\fP value of 0 means you should call

\fIcurl_multi_socket_action(3)\fP or \fIcurl_multi_perform(3)\fP (once) as soon

as possible.



\fBtimer_callback\fP will only be called when the \fBtimeout_ms\fP changes.

The \fBtimer_callback\fP will only be called when the timeout expire time is

changed.



The \fBuserp\fP pointer is set with \fICURLMOPT_TIMERDATA(3)\fP.