[sysprof: 59/63] collector: disable re-entrancy during initialization

[Christian Hergert <chergert src gnome org>]

commit 5d20c3f6cfe9014ecc01100d423a4473d8143276
Author: Christian Hergert <chergert redhat com>
Date:   Thu Jul 2 15:19:16 2020 -0700

    collector: disable re-entrancy during initialization
    
    When creating a new collector, we need to prevent the following
    call to sysprof_malloc0() from re-entering us into the same
    position.

 src/libsysprof-capture/sysprof-collector.c | 6 ++++++
 1 file changed, 6 insertions(+)
---
diff --git a/src/libsysprof-capture/sysprof-collector.c b/src/libsysprof-capture/sysprof-collector.c
index 1d0c57b..b99cd1b 100644
--- a/src/libsysprof-capture/sysprof-collector.c
+++ b/src/libsysprof-capture/sysprof-collector.c
@@ -410,6 +410,12 @@ sysprof_collector_get (void)
   {
     SysprofCollector *self, *old_collector;
 
+    /* First set the collector to invalid so anything recursive
+     * here fails instead of becoming re-entrant.
+     */
+    pthread_setspecific (collector_key, COLLECTOR_INVALID);
+
+    /* Now we can malloc without ending up here again */
     self = sysprof_malloc0 (sizeof (SysprofCollector));
     if (self == NULL)
       return COLLECTOR_INVALID;