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-rw-r--r--linuxthreads/sysdeps/pthread/getcpuclockid.c49
1 files changed, 49 insertions, 0 deletions
diff --git a/linuxthreads/sysdeps/pthread/getcpuclockid.c b/linuxthreads/sysdeps/pthread/getcpuclockid.c
new file mode 100644
index 0000000000..032caeb081
--- /dev/null
+++ b/linuxthreads/sysdeps/pthread/getcpuclockid.c
@@ -0,0 +1,49 @@
+/* Copyright (C) 2000, 2001, 2004 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
+   modify it under the terms of the GNU Lesser General Public License as
+   published by the Free Software Foundation; either version 2.1 of the
+   License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; see the file COPYING.LIB.  If not,
+   write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+   Boston, MA 02111-1307, USA.  */
+
+#include <errno.h>
+#include <pthread.h>
+#include <sys/time.h>
+#include <time.h>
+#include <internals.h>
+
+int
+pthread_getcpuclockid (pthread_t thread_id, clockid_t *clock_id)
+{
+#ifdef CLOCK_THREAD_CPUTIME_ID
+  /* We need to store the thread ID in the CLOCKID variable together
+     with a number identifying the clock.  We reserve the low 3 bits
+     for the clock ID and the rest for the thread ID.  This is
+     problematic if the thread ID is too large.  But 29 bits should be
+     fine.
+
+     If some day more clock IDs are needed the ID part can be
+     enlarged.  The IDs are entirely internal.  */
+  if (2 * PTHREAD_THREADS_MAX
+      >= 1 << (8 * sizeof (*clock_id) - CLOCK_IDFIELD_SIZE))
+    return ERANGE;
+
+  /* Store the number.  */
+  *clock_id = CLOCK_THREAD_CPUTIME_ID | (thread_id << CLOCK_IDFIELD_SIZE);
+
+  return 0;
+#else
+  /* We don't have a timer for that.  */
+  return ENOENT;
+#endif
+}