[libgomp,nvptx] Fix libgomp.c/target-5.c compilation

[libgomp, nvptx] Fix libgomp.c/target-5.c compilation

Libgomp test-case libgomp.c/target-5.c is failing to compile when building for
x86_64 with nvptx accelerator due to missing:
- getpid
- gethostname
- isatty (pulled in by fwrite)
in the nvptx newlib.

This patch fixes the build failure by:
- adding a function gomp_print_string which limits the use of fwrite to a single
  location (affinity-fmt.c), and
- creating an nvptx version of affinity-fmt.c, which:
  - implements fwrite using write
  - overrides the configure test results HAVE_GETPID and HAVE_GETHOSTNAME

Build and reg-tested on x86_64 with nvptx accelerator.

2018-12-13  Tom de Vries  <tdevries@suse.de>

	* affinity-fmt.c (gomp_print_string): New function, factored out of ...
	(omp_display_affinity, gomp_display_affinity_thread): ... here, and ...
	* fortran.c (omp_display_affinity_): ... here.
	* libgomp.h (gomp_print_string): Declare.
	* config/nvptx/affinity-fmt.c: New file.  Include affinity-fmt.c,
	undefining HAVE_GETPID and HAVE_GETHOSTNAME, and mapping fwrite to
	write.

---
 libgomp/affinity-fmt.c              | 14 +++++++---
 libgomp/config/nvptx/affinity-fmt.c | 52 +++++++++++++++++++++++++++++++++++++
 libgomp/fortran.c                   |  4 +--
 libgomp/libgomp.h                   |  1 +
 4 files changed, 65 insertions(+), 6 deletions(-)

diff --git a/libgomp/affinity-fmt.c b/libgomp/affinity-fmt.c
index 9e5c5f754eb..1447597e7f7 100644
--- a/libgomp/affinity-fmt.c
+++ b/libgomp/affinity-fmt.c
@@ -37,6 +37,12 @@ 
 #include <sys/utsname.h>
 #endif
 
+void
+gomp_print_string (const char *str, size_t len)
+{
+  fwrite (str, 1, len, stderr);
+}
+
 void
 gomp_set_affinity_format (const char *format, size_t len)
 {
@@ -456,13 +462,13 @@  omp_display_affinity (const char *format)
   if (ret < sizeof buf)
     {
       buf[ret] = '\n';
-      fwrite (buf, 1, ret + 1, stderr);
+      gomp_print_string (buf, ret + 1);
       return;
     }
   b = gomp_malloc (ret + 1);
   ialias_call (omp_capture_affinity) (b, ret + 1, format);
   b[ret] = '\n';
-  fwrite (b, 1, ret + 1, stderr);
+  gomp_print_string (b, ret + 1);
   free (b);
 }
 
@@ -477,13 +483,13 @@  gomp_display_affinity_thread (gomp_thread_handle handle,
   if (ret < sizeof buf)
     {
       buf[ret] = '\n';
-      fwrite (buf, 1, ret + 1, stderr);
+      gomp_print_string (buf, ret + 1);
       return;
     }
   b = gomp_malloc (ret + 1);
   gomp_display_affinity (b, ret + 1, gomp_affinity_format_var,
   			 handle, ts, place);
   b[ret] = '\n';
-  fwrite (b, 1, ret + 1, stderr);
+  gomp_print_string (b, ret + 1);
   free (b);
 }
diff --git a/libgomp/config/nvptx/affinity-fmt.c b/libgomp/config/nvptx/affinity-fmt.c
new file mode 100644
index 00000000000..ff1cbfcc4f8
--- /dev/null
+++ b/libgomp/config/nvptx/affinity-fmt.c
@@ -0,0 +1,52 @@ 
+/* Copyright (C) 2018 Free Software Foundation, Inc.
+
+   This file is part of the GNU Offloading and Multi Processing Library
+   (libgomp).
+
+   Libgomp is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3, or (at your option)
+   any later version.
+
+   Libgomp 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 General Public License for
+   more details.
+
+   Under Section 7 of GPL version 3, you are granted additional
+   permissions described in the GCC Runtime Library Exception, version
+   3.1, as published by the Free Software Foundation.
+
+   You should have received a copy of the GNU General Public License and
+   a copy of the GCC Runtime Library Exception along with this program;
+   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "libgomp.h"
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#ifdef HAVE_INTTYPES_H
+# include <inttypes.h>  /* For PRIx64.  */
+#endif
+#ifdef HAVE_UNAME
+#include <sys/utsname.h>
+#endif
+
+/* The HAVE_GETPID and HAVE_GETHOSTNAME configure tests are passing for nvptx,
+   while the nvptx newlib implementation does not support those functions.
+   Override the configure test results here.  */
+#undef HAVE_GETPID
+#undef HAVE_GETHOSTNAME
+
+/* The nvptx newlib implementation does not support fwrite, but it does support
+   write.  Map fwrite to write for size == 1.  */
+#undef fwrite
+#define fwrite(ptr, size, nmemb, stream) \
+  ((size) == 1 ? write (1, (ptr), (nmemb)) : 0)
+
+#include "../../affinity-fmt.c"
+
diff --git a/libgomp/fortran.c b/libgomp/fortran.c
index 0157baec648..328bf9c8450 100644
--- a/libgomp/fortran.c
+++ b/libgomp/fortran.c
@@ -626,7 +626,7 @@  omp_display_affinity_ (const char *format, size_t format_len)
   if (ret < sizeof buf)
     {
       buf[ret] = '\n';
-      fwrite (buf, 1, ret + 1, stderr);
+      gomp_print_string (buf, ret + 1);
     }
   else
     {
@@ -635,7 +635,7 @@  omp_display_affinity_ (const char *format, size_t format_len)
 			     format_len ? fmt : gomp_affinity_format_var,
 			     gomp_thread_self (), &thr->ts, thr->place);
       b[ret] = '\n';
-      fwrite (b, 1, ret + 1, stderr);
+      gomp_print_string (b, ret + 1);
       free (b);
     }
   if (fmt && fmt != fmt_buf)
diff --git a/libgomp/libgomp.h b/libgomp/libgomp.h
index 7eacb45db66..8105e640e32 100644
--- a/libgomp/libgomp.h
+++ b/libgomp/libgomp.h
@@ -751,6 +751,7 @@  extern void gomp_display_affinity_place (char *, size_t, size_t *, int);
 
 /* affinity-fmt.c */
 
+extern void gomp_print_string (const char *str, size_t len);
 extern void gomp_set_affinity_format (const char *, size_t);
 extern void gomp_display_string (char *, size_t, size_t *, const char *,
 				 size_t);