[svn-r6383] Purpose:

    New feature for developers.

Description:
    Added "function stack" tracing to library.  This allows developers (there
    is no public API) to call H5FS_print within the library and get a listing
    of the functions traversed to reach that point in the library.  Eventually,
    I may add support for reporting the parameters to each function also...

    Mainly for debugging parallel I/O programs, but I think it will come in
    handy in other cases also.

    The function stack tracking is controlled with a configure switch:
    --enable-funcstack, which defaults to enabled currently.  When we branch
    for 1.6, we should change the default setting on the branch to be disabled.

    Also, added a destructor to the thread-specific keys when thread-safety is
    turned on in the library.  Otherwise, they were leaking memory and causing
    difficult to debug errors in threaded programs (like the test/ttsafe test).

Platforms tested:
    Tested h5committest {arabica (fortran), eirene (fortran, C++)
	modi4 (parallel, fortran)}

    FreeBSD 4.7 (sleipnir) w/thread-safety enabled.

Misc. update:
    Updated MANIFEST with new files added (src/H5FS.c & src/H5FDprivate.h)

    Update release_docs/RELEASE with thread-safety bug fix.

1 files changed, 36 insertions, 37 deletions

diff --git a/src/H5TS.c b/src/H5TS.c
index ce3d5ef..c577ebc 100644
--- a/src/H5TS.c
+++ b/src/H5TS.c
@@ -30,6 +30,7 @@ typedef struct H5TS_cancel_struct {
 /* Global variable definitions */
 pthread_once_t H5TS_first_init_g = PTHREAD_ONCE_INIT;
 pthread_key_t H5TS_errstk_key_g;
+pthread_key_t H5TS_funcstk_key_g;
 pthread_key_t H5TS_cancel_key_g;
 hbool_t H5TS_allow_concurrent_g = FALSE; /* concurrent APIs override this */
 
@@ -38,6 +39,36 @@ hbool_t H5TS_allow_concurrent_g = FALSE; /* concurrent APIs override this */
 static void H5TS_mutex_init(H5TS_mutex_t *mutex);
 #endif /* NOT_USED */
 
+
+/*--------------------------------------------------------------------------
+ * NAME
+ *    H5TS_key_destructor
+ *
+ * USAGE
+ *    H5TS_key_destructor()
+ * 
+ * RETURNS
+ *
+ * DESCRIPTION
+ *   Frees the memory for a key.  Called by each thread as it exits.
+ *   Currently all the thread-specific information for all keys are simple
+ *   structures allocated with malloc, so we can free them all uniformly.
+ *
+ * PROGRAMMER: Quincey Koziol
+ *             February 7, 2003
+ *
+ * MODIFICATIONS:
+ *
+ *--------------------------------------------------------------------------
+ */
+static void
+H5TS_key_destructor(void *key_val)
+{
+    /* Use HDfree here instead of H5MM_xfree(), to avoid calling the H5FS routines */
+    if(key_val!=NULL)
+        HDfree(key_val);
+}
+
 /*--------------------------------------------------------------------------
  * NAME
  *    H5TS_first_thread_init
@@ -73,46 +104,14 @@ H5TS_first_thread_init(void)
     H5_g.init_lock.lock_count = 0;
 
     /* initialize key for thread-specific error stacks */
-    pthread_key_create(&H5TS_errstk_key_g, NULL);
+    pthread_key_create(&H5TS_errstk_key_g, H5TS_key_destructor);
 
-    /* initialize key for thread cancellability mechanism */
-    pthread_key_create(&H5TS_cancel_key_g, NULL);
-}
+    /* initialize key for thread-specific function stacks */
+    pthread_key_create(&H5TS_funcstk_key_g, H5TS_key_destructor);
 
-#ifdef NOT_USED
-/*--------------------------------------------------------------------------
- * NAME
- *    H5TS_mutex_init
- *
- * USAGE
- *    H5TS_mutex_init(&mutex_var)
- * 
- * RETURNS
- *
- * DESCRIPTION
- *    Recursive lock semantics for HDF5 (lock initialization) -
- *    Multiple acquisition of a lock by a thread is permitted with a
- *    corresponding unlock operation required.
- *
- * PROGRAMMER: Chee Wai LEE
- *             May 2, 2000
- *
- * MODIFICATIONS:
- *
- *    19 May 2000, Bill Wendling
- *    Changed (*foo). form of accessing structure members to the -> form.
- *
- *--------------------------------------------------------------------------
- */
-static void
-H5TS_mutex_init(H5TS_mutex_t *mutex)
-{
-    H5_g.init_lock.owner_thread = NULL;
-    pthread_mutex_init(&mutex->atomic_lock, NULL);
-    pthread_cond_init(&mutex->cond_var, NULL);
-    mutex->lock_count = 0;
+    /* initialize key for thread cancellability mechanism */
+    pthread_key_create(&H5TS_cancel_key_g, H5TS_key_destructor);
 }
-#endif /* NOT_USED */
 
 /*--------------------------------------------------------------------------
  * NAME