As well as patches from Anders, this commit includes some older changes

that hadn't been checked in. Those are to finish off the original TSD management
scheme which will now start to be replaced by John Bossom's implementation.
Anders' description of his changes:-
Fixes the problem with
`TryEnterCriticalSection' on w95 systems. Instead
of directly calling `TryEnterCriticalSection' it
tries to get a pointer at DLL startup and only calls
the function if it exists. See ChangeLog for things
changed.
1998-12-05  Anders Norlander  <anorland@hem2.passagen.se>
	* implement.h (_pthread_try_enter_critical_section): New extern
	* dll.c (_pthread_try_enter_critical_section): New pointer to
	TryEnterCriticalSection if it exists; otherwise NULL.
	* dll.c (PthreadsEntryPoint):
	Initialize _pthread_try_enter_critical_section at startup
	and release kernel32 handle when DLL is being unloaded.
	* mutex.c (pthread_mutex_trylock): Replaced check for NT with
	a check if _pthread_try_enter_critical_section is valid
	pointer to a function. Call _pthread_try_enter_critical_section
	instead of TryEnterCriticalSection to avoid errors on Win95.
Sun Nov 15 21:24:06 1998  Ross Johnson  <rpj@ixobrychus.canberra.edu.au>
	* cleanup.c (_pthread_destructor_run_all): Declare missing void * arg.
	Fixup CVS merge conflicts.
Fri Oct 30 15:15:50 1998  Ross Johnson  <rpj@swan.canberra.edu.au>
	* cleanup.c (_pthread_handler_push): Fixed bug appending new
	handler to list reported by Peter Slacik
	<Peter.Slacik@leibinger.freinet.de>.
	(new_thread): Rename poorly named local variable to
	"new_handler".
Sat Oct 24 18:34:59 1998  Ross Johnson  <rpj@ixobrychus.canberra.edu.au>
	* global.c: Add TSD key management array and index declarations.
	* implement.h: Ditto for externs.
Fri Oct 23 00:08:09 1998  Ross Johnson  <rpj@ixobrychus.canberra.edu.au>
	* implement.h (_PTHREAD_TSD_KEY_REUSE): Add enum.
	* private.c (_pthread_delete_thread): Add call to
	_pthread_destructor_run_all() to clean up the threads keys.
	* cleanup.c (_pthread_destructor_run_all): Check for no more dirty
	keys to run destructors on. Assume that the destructor call always
	succeeds and set the key value to NULL.

1 files changed, 3 insertions, 6 deletions

diff --git a/mutex.c b/mutex.c
index 03f3f48..aabee9e 100644
--- a/mutex.c
+++ b/mutex.c
@@ -88,12 +88,9 @@ pthread_mutex_unlock(pthread_mutex_t *mutex)
 int
 pthread_mutex_trylock(pthread_mutex_t *mutex)
 {
-  /* Typically evaluates to 31. */
-  int numbits = (sizeof(DWORD) * 8) - 1;
-
-  if ((GetVersion() >> numbits) != 1)
+  if (_pthread_try_enter_critical_section == NULL)
     {
-      /* We're not on Windows NT; return ENOSYS. */
+      /* TryEnterCriticalSection does not exist in the OS; return ENOSYS. */
       return ENOSYS;
     }
       
@@ -107,5 +104,5 @@ pthread_mutex_trylock(pthread_mutex_t *mutex)
       pthread_mutex_init(mutex, NULL);
     }
 
-  return (TryEnterCriticalSection(&mutex->cs) != TRUE) ? EBUSY : 0;
+  return ((*_pthread_try_enter_critical_section)(&mutex->cs) != TRUE) ? EBUSY : 0;
 }