[NaCl SDK] nacl_io: Fix newlib IRT interception of isatty().

native_client_sdk/src/tests/nacl_io_test/kernel_wrap_test.cc

 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // The linux host build of nacl_io can't do wrapping of syscalls so all
 // these tests must be disabled.
 #if !defined(__linux__)
 
 #include <unistd.h>
 
@@ skipping 278 matching lines @@
   char buffer[] = "ioctl";
   EXPECT_CALL(mock, ioctl(kDummyInt, kDummyInt2, _))
       .WillOnce(Return(kDummyInt3));
   EXPECT_EQ(kDummyInt3, ioctl(kDummyInt, kDummyInt2, buffer));
 }
 
 #if !defined(__BIONIC__)
 TEST_F(KernelWrapTest, isatty) {
   EXPECT_CALL(mock, isatty(kDummyInt)).WillOnce(Return(kDummyInt2));
   EXPECT_EQ(kDummyInt2, isatty(kDummyInt));
+
+  // This test verifies that the IRT interception wrapper for isatty
+  // ignores the value of errno when isatty() returns 1.  We had a bug
+  // where returning 1 from ki_isatty resulted in errno being returned
+  // by the IRT interface.
+  errno = kDummyInt3;
+  EXPECT_CALL(mock, isatty(kDummyInt)).WillOnce(Return(1));
+  EXPECT_EQ(1, isatty(kDummyInt));
 }
 #endif
 
 TEST_F(KernelWrapTest, kill) {
   EXPECT_CALL(mock, kill(kDummyInt, kDummyInt2)).WillOnce(Return(kDummyInt3));
   EXPECT_EQ(kDummyInt3, kill(kDummyInt, kDummyInt2));
 }
 
 TEST_F(KernelWrapTest, lchown) {
   EXPECT_CALL(mock, lchown(kDummyConstChar, kDummyUid, kDummyGid))
@@ skipping 421 matching lines @@
   int dummy_val;
   EXPECT_CALL(mock, socketpair(kDummyInt, kDummyInt2, kDummyInt3, &dummy_val))
       .WillOnce(Return(kDummyInt4));
   EXPECT_EQ(kDummyInt4,
             socketpair(kDummyInt, kDummyInt2, kDummyInt3, &dummy_val));
 }
 
 #endif  // PROVIDES_SOCKET_API
 
 #endif  // __linux__