libpthread/

2005-05-02  Neal H. Walfield  <neal@gnu.org>

	* pthread/pt-alloc.c (__pthread_alloc): Set the thread id to the
	table index plus one.
	* pthread/pt-internal.h (__pthread_getid): Index __pthread_threads
	using THREAD - 1, not THREAD.
	(__pthread_setid): Likewise.
	* pthread/pt-create.c (__pthread_create_internal): Likewise.

	* sysdeps/generic/pt-mutex-trylock.c (__pthread_mutex_trylock):
	When returning EBUSY, don't forget to first unlock MUTEX->__HELD.

3 files changed, 16 insertions, 13 deletions

diff --git a/pthread/pt-alloc.c b/pthread/pt-alloc.c
index 5cdc85d..e8d3c03 100644
--- a/pthread/pt-alloc.c
+++ b/pthread/pt-alloc.c
@@ -1,5 +1,5 @@
 /* Allocate a new thread structure.
-   Copyright (C) 2000, 2002 Free Software Foundation, Inc.
+   Copyright (C) 2000, 2002, 2005 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -139,10 +139,10 @@ __pthread_alloc (struct __pthread **pthread)
 
   if (__pthread_num_threads < __pthread_max_threads)
     {
-      /* We have a free slot.  Use the slot number as
-         the thread ID for the new thread.  */
-      new->thread = __pthread_num_threads++;
-      __pthread_threads[new->thread] = NULL;
+      /* We have a free slot.  Use the slot number plus one as the
+         thread ID for the new thread.  */
+      new->thread = 1 + __pthread_num_threads++;
+      __pthread_threads[new->thread - 1] = NULL;
 
       pthread_rwlock_unlock (&__pthread_threads_lock);
 
@@ -203,8 +203,8 @@ __pthread_alloc (struct __pthread **pthread)
   __pthread_threads = threads;
 
   /* And allocate ourselves one of the newly created slots.  */
-  new->thread = __pthread_num_threads++;
-  __pthread_threads[new->thread] = NULL;
+  new->thread = 1 + __pthread_num_threads++;
+  __pthread_threads[new->thread - 1] = NULL;
 
   pthread_rwlock_unlock (&__pthread_threads_lock);
 
diff --git a/pthread/pt-create.c b/pthread/pt-create.c
index 0295a0a..cf5b32d 100644
--- a/pthread/pt-create.c
+++ b/pthread/pt-create.c
@@ -1,5 +1,5 @@
 /* Thread creation.
-   Copyright (C) 2000, 2002 Free Software Foundation, Inc.
+   Copyright (C) 2000, 2002, 2005 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -168,7 +168,7 @@ __pthread_create_internal (struct __pthread **thread,
      other thread should be using this entry (we also assume that the
      store is atomic).  */
   pthread_rwlock_rdlock (&__pthread_threads_lock);
-  __pthread_threads[pthread->thread] = pthread;
+  __pthread_threads[pthread->thread - 1] = pthread;
   pthread_rwlock_unlock (&__pthread_threads_lock);
 
   /* At this point it is possible to guess our pthread ID.  We have to
diff --git a/pthread/pt-internal.h b/pthread/pt-internal.h
index a32345c..75631db 100644
--- a/pthread/pt-internal.h
+++ b/pthread/pt-internal.h
@@ -1,5 +1,5 @@
 /* Internal defenitions for pthreads library.
-   Copyright (C) 2000 Free Software Foundation, Inc.
+   Copyright (C) 2000, 2005 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -134,20 +134,23 @@ extern int __pthread_num_threads;
 /* Concurrency hint.  */
 extern int __pthread_concurrency;
 
-/* Array of __pthread structures and its lock.  */
+/* Array of __pthread structures and its lock.  Indexed by the pthread
+   id minus one.  (Why not just use the pthread id?  Because some
+   brain-dead users of the pthread interface incorrectly assume that 0
+   is an invalid pthread id.)  */
 extern struct __pthread **__pthread_threads;
 extern pthread_rwlock_t __pthread_threads_lock;
 
 #define __pthread_getid(thread) \
   ({ struct __pthread *__t;                                                  \
      pthread_rwlock_rdlock (&__pthread_threads_lock);                        \
-     __t = __pthread_threads[thread];                                        \
+     __t = __pthread_threads[thread - 1];                                    \
      pthread_rwlock_unlock (&__pthread_threads_lock);                        \
      __t; })
 
 #define __pthread_setid(thread, pthread) \
   pthread_rwlock_wrlock (&__pthread_threads_lock);                           \
-  __pthread_threads[thread] = pthread;                                       \
+  __pthread_threads[thread - 1] = pthread;                                   \
   pthread_rwlock_unlock (&__pthread_threads_lock);
 
 /* Similar to pthread_self, but returns the thread descriptor instead