nptl: Replace some stubs with the Linux implementation

The stubs for pthread_getaffinity_np, pthread_getname_np,
pthread_setaffinity_np, pthread_setname_np are replaced, and corresponding
tests are moved.

After the removal of the NaCl port, nptl is Linux-specific, and the stubs
are no longer needed.  This effectively reverts commit
c76d1ff5149bd03210f2bb8cd64446c51618d016 ("NPTL: Add stubs for Linux-only
extension functions.").

Reviewed-by: Carlos O'Donell <carlos@redhat.com>

1 files changed, 43 insertions, 6 deletions

diff --git a/nptl/pthread_getname.c b/nptl/pthread_getname.c
index b771f2e..c78cccf 100644
--- a/nptl/pthread_getname.c
+++ b/nptl/pthread_getname.c
@@ -1,5 +1,5 @@
-/* pthread_getname_np -- Get thread name.  Stub version.
-   Copyright (C) 2014-2020 Free Software Foundation, Inc.
+/* pthread_getname_np -- Get  thread name.  Linux version
+   Copyright (C) 2010-2020 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
@@ -17,16 +17,53 @@
    not, see <https://www.gnu.org/licenses/>.  */
 
 #include <errno.h>
+#include <fcntl.h>
 #include <pthreadP.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/prctl.h>
+
+#include <not-cancel.h>
+
 
 int
 pthread_getname_np (pthread_t th, char *buf, size_t len)
 {
   const struct pthread *pd = (const struct pthread *) th;
 
-  if (INVALID_TD_P (pd))
-    return ESRCH;
+  /* Unfortunately the kernel headers do not export the TASK_COMM_LEN
+     macro.  So we have to define it here.  */
+#define TASK_COMM_LEN 16
+  if (len < TASK_COMM_LEN)
+    return ERANGE;
+
+  if (pd == THREAD_SELF)
+    return prctl (PR_GET_NAME, buf) ? errno : 0;
+
+#define FMT "/proc/self/task/%u/comm"
+  char fname[sizeof (FMT) + 8];
+  sprintf (fname, FMT, (unsigned int) pd->tid);
+
+  int fd = __open64_nocancel (fname, O_RDONLY);
+  if (fd == -1)
+    return errno;
+
+  int res = 0;
+  ssize_t n = TEMP_FAILURE_RETRY (__read_nocancel (fd, buf, len));
+  if (n < 0)
+    res = errno;
+  else
+    {
+      if (buf[n - 1] == '\n')
+	buf[n - 1] = '\0';
+      else if (n == len)
+	res = ERANGE;
+      else
+	buf[n] = '\0';
+    }
+
+  __close_nocancel_nostatus (fd);
 
-  return ENOSYS;
+  return res;
 }
-stub_warning (pthread_getname_np)