[glibc] htl: Let pthread_self and cancellability called early

[Samuel Thibault <sthibaul@sourceware.org>]

https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=70ff58ced45edf0e3483eddbb61203037bdfdaaa

commit 70ff58ced45edf0e3483eddbb61203037bdfdaaa
Author: Samuel Thibault <samuel.thibault@ens-lyon.org>
Date:   Thu Jul 28 22:01:49 2022 +0200

    htl: Let pthread_self and cancellability called early
    
    When applications redirect some functions they might get called before
    libpthread is fully initialized.  They may still expected pthread_self
    and cancellable functions to work, so cope with such calls in that
    situation.

Diff:
---
 htl/cancellation.c | 8 ++++++++
 htl/pt-self.c      | 8 +++++++-
 2 files changed, 15 insertions(+), 1 deletion(-)

diff --git a/htl/cancellation.c b/htl/cancellation.c
index a5d5d2ac04..7d38944718 100644
--- a/htl/cancellation.c
+++ b/htl/cancellation.c
@@ -25,6 +25,10 @@ int __pthread_enable_asynccancel (void)
   struct __pthread *p = _pthread_self ();
   int oldtype;
 
+  if (___pthread_self == NULL)
+    /* We are not initialized yet, we can't be cancelled anyway.  */
+    return PTHREAD_CANCEL_DEFERRED;
+
   __pthread_mutex_lock (&p->cancel_lock);
   oldtype = p->cancel_type;
   p->cancel_type = PTHREAD_CANCEL_ASYNCHRONOUS;
@@ -39,6 +43,10 @@ void __pthread_disable_asynccancel (int oldtype)
 {
   struct __pthread *p = _pthread_self ();
 
+  if (___pthread_self == NULL)
+    /* We are not initialized yet, we can't be cancelled anyway.  */
+    return;
+
   __pthread_mutex_lock (&p->cancel_lock);
   p->cancel_type = oldtype;
   __pthread_mutex_unlock (&p->cancel_lock);
diff --git a/htl/pt-self.c b/htl/pt-self.c
index 6fd3c98b82..e05ec69bf5 100644
--- a/htl/pt-self.c
+++ b/htl/pt-self.c
@@ -24,7 +24,13 @@
 pthread_t
 __pthread_self (void)
 {
-  struct __pthread *self = _pthread_self ();
+  struct __pthread *self;
+
+  if (___pthread_self == NULL)
+    /* We are not initialized yet, we are the first thread.  */
+    return 1;
+
+  self = _pthread_self ();
   assert (self != NULL);
 
   return self->thread;