core: fix random timeouts when a lot of concurrent processes are launched with hook_process (issue #2033)

ChangeLog.adoc

@@ -15,6 +15,7 @@ For a list of important changes that require manual actions, please look at rele
 
 Bug fixes::
 
+  * core: fix random timeouts when a lot of concurrent processes are launched with hook_process (issue #2033)
   * irc: revert compute of nick colors to case sensitive way, deprecate again infos "irc_nick_color" and "irc_nick_color_name" (issue #194, issue #2032)
 
 Build::

src/core/hook/wee-hook-connect.c

@@ -270,7 +270,7 @@ hook_connect_free_data (struct t_hook *hook)
     if (HOOK_CONNECT(hook, child_pid) > 0)
     {
         kill (HOOK_CONNECT(hook, child_pid), SIGKILL);
-        hook_schedule_clean_children ();
+        hook_schedule_clean_process (HOOK_CONNECT(hook, child_pid));
         HOOK_CONNECT(hook, child_pid) = 0;
     }
     if (HOOK_CONNECT(hook, child_read) != -1)

src/core/hook/wee-hook-process.c

@@ -862,7 +862,7 @@ hook_process_free_data (struct t_hook *hook)
     if (HOOK_PROCESS(hook, child_pid) > 0)
     {
         kill (HOOK_PROCESS(hook, child_pid), SIGKILL);
-        hook_schedule_clean_children ();
+        hook_schedule_clean_process (HOOK_PROCESS(hook, child_pid));
         HOOK_PROCESS(hook, child_pid) = 0;
     }
     if (HOOK_PROCESS(hook, child_read[HOOK_PROCESS_STDIN]) != -1)

src/core/wee-hook.c

@@ -28,6 +28,7 @@
 #include <string.h>
 #include <time.h>
 #include <sys/socket.h>
+#include <sys/wait.h>
 #include <errno.h>
 
 #include "weechat.h"
@@ -38,7 +39,6 @@
 #include "wee-log.h"
 #include "wee-signal.h"
 #include "wee-string.h"
-#include "wee-sys.h"
 #include "wee-util.h"
 #include "../gui/gui-chat.h"
 #include "../plugins/plugin.h"
@@ -629,20 +629,19 @@ hook_set (struct t_hook *hook, const char *property, const char *value)
 }
 
 /*
- * Callback used to clean all children (forked processes) by acknowledging
- * their end.
+ * Callback used to clean a process (forked processes) by acknowledging its end.
  */
 
 int
-hook_timer_clean_children_cb (const void *pointer, void *data,
-                              int remaining_calls)
+hook_timer_clean_process_cb (const void *pointer, void *data,
+                             int remaining_calls)
 {
     /* make C compiler happy */
     (void) pointer;
     (void) data;
     (void) remaining_calls;
 
-    sys_waitpid ();
+    waitpid (*((pid_t *)data), NULL, WNOHANG);
 
     return WEECHAT_RC_OK;
 }
@@ -652,9 +651,18 @@ hook_timer_clean_children_cb (const void *pointer, void *data,
  */
 
 void
-hook_schedule_clean_children ()
+hook_schedule_clean_process (pid_t pid)
 {
-    hook_timer (NULL, 100, 0, 1, &hook_timer_clean_children_cb, NULL, NULL);
+    pid_t *temp_pid;
+
+    /* temp_pid will be freed when the timer is removed */
+    temp_pid = malloc (sizeof (*temp_pid));
+    if (temp_pid)
+    {
+        *temp_pid = pid;
+        hook_timer (NULL, 100, 0, 1,
+                    &hook_timer_clean_process_cb, NULL, temp_pid);
+    }
 }
 
 /*

src/core/wee-hook.h

@@ -146,7 +146,7 @@ extern void hook_callback_end (struct t_hook *hook,
 extern char *hook_get_description (struct t_hook *hook);
 extern void hook_set (struct t_hook *hook, const char *property,
                       const char *value);
-extern void hook_schedule_clean_children ();
+extern void hook_schedule_clean_process (pid_t pid);
 extern void unhook (struct t_hook *hook);
 extern void unhook_all_plugin (struct t_weechat_plugin *plugin,
                                const char *subplugin);