[NaCl SDK] nacl_io: Enable isatty running under sel_ldr.

native_client_sdk/src/libraries/nacl_io/kernel_wrap_newlib.cc

Index: native_client_sdk/src/libraries/nacl_io/kernel_wrap_newlib.cc
diff --git a/native_client_sdk/src/libraries/nacl_io/kernel_wrap_newlib.cc b/native_client_sdk/src/libraries/nacl_io/kernel_wrap_newlib.cc
index 0809866547ba522e6b8720ddeab08f0fb86c6aa7..47a8024f2bf673ee6f00051720a37f6a275f56ca 100644
--- a/native_client_sdk/src/libraries/nacl_io/kernel_wrap_newlib.cc
+++ b/native_client_sdk/src/libraries/nacl_io/kernel_wrap_newlib.cc
@@ -67,6 +67,7 @@ extern struct nacl_irt_memory __libnacl_irt_memory;
   OP(dev_fdio, fsync); \
   OP(dev_fdio, fdatasync); \
   OP(dev_fdio, ftruncate); \
+  OP(dev_fdio, isatty); \
   OP(dev_filename, open); \
   OP(dev_filename, stat); \
   OP(dev_filename, mkdir); \
@@ -152,6 +153,13 @@ int WRAP(ftruncate)(int fd, off_t length) {
   return (ki_ftruncate(fd, length) < 0) ? errno : 0;
 }
 
+int WRAP(isatty)(int fd, int* result) {
+  *result = ki_isatty(fd);
+  if (*result == 1)
+    return errno;
+  return 0;
+}
+
 int WRAP(mmap)(void** addr, size_t length, int prot, int flags, int fd,
                off_t offset) {
   if (flags & MAP_ANONYMOUS)
@@ -266,6 +274,11 @@ int _real_fstat(int fd, struct stat* buf) {
   return REAL(fstat)(fd, buf);
 }
 
+int _real_isatty(int fd, int* result) {
+  CHECK_REAL(isatty);
+  return REAL(isatty)(fd, result);
+}
+
 int _real_getdents(int fd, void* nacl_buf, size_t nacl_count, size_t* nread) {
   CHECK_REAL(getdents);
   return REAL(getdents)(fd, static_cast<dirent*>(nacl_buf), nacl_count, nread);