PERFORCE change 57145 for review

[Marcel Moolenaar]

http://perforce.freebsd.org/chv.cgi?CH=57145

Change 57145 by marcel at marcel_nfs on 2004/07/12 03:41:54

	libc_r has initialized _thread_run with something other than
	a NULL pointer. Since we may be asked to map a LWP to a thread
	handle before libc_r has been initialized and we should not
	return a handle in that case, we need to check for something
	that indicates whether libc_r is initialized. Use _thread_initial
	for that.

Affected files ...

.. //depot/projects/gdb/lib/libthread_db/libc_r_db.c#3 edit

Differences ...

==== //depot/projects/gdb/lib/libthread_db/libc_r_db.c#3 (text+ko) ====

@@ -41,6 +41,7 @@
 struct td_thragent {
 	TD_THRAGENT_FIELDS;
 	struct ps_prochandle	*ta_ph;
+	psaddr_t ta_thread_initial;
 	psaddr_t ta_thread_list;
 	psaddr_t ta_thread_run;
 	int	ta_ofs_ctx;
@@ -91,9 +92,15 @@
 libc_r_db_ta_map_lwp2thr(const td_thragent_t *ta, lwpid_t lwpid,
     td_thrhandle_t *th)
 {
+	psaddr_t addr;
 	ps_err_e err;
 
 	th->th_ta = ta;
+	err = ps_pread(ta->ta_ph, ta->ta_thread_initial, &addr, sizeof(addr));
+	if (err != PS_OK)
+		return (TD_ERR);
+	if (addr == NULL)
+		return (TD_NOLWP);
 	err = ps_pread(ta->ta_ph, ta->ta_thread_run, &th->th_thread,
 	    sizeof(psaddr_t));
 	return ((err == PS_OK) ? TD_OK : TD_ERR);
@@ -112,6 +119,10 @@
 
 	ta->ta_ph = ph;
 
+	err = ps_pglobal_lookup(ph, NULL, "_thread_initial",
+	    &ta->ta_thread_initial);
+	if (err != PS_OK)
+		goto fail;
 	err = ps_pglobal_lookup(ph, NULL, "_thread_list", &ta->ta_thread_list);
 	if (err != PS_OK)
 		goto fail;