[PATCH] D51558: [Windows] Convert from UTF-8 to UTF-16 when writing to a Windows console

[Zachary Turner via Phabricator via llvm-commits]

zturner added inline comments.


================
Comment at: llvm/lib/Support/raw_ostream.cpp:572
+#ifdef _WIN32
+  IsConsole = ::GetFileType((HANDLE)::_get_osfhandle(fd)) == FILE_TYPE_CHAR;
+#endif
----------------
You can use `llvm::sys::Process::FileDescriptorIsDisplayed(fd)` here.  Also, no need to put it behind the `#ifdef`, the member variable can be set correctly regardless of platform.


================
Comment at: llvm/lib/Support/raw_ostream.cpp:632
+// probably the best compromise we can make.
+static bool write_console_impl(int FD, const char *Ptr, size_t Size) {
+  SmallVector<wchar_t, 256> WideText;
----------------
`StringRef Data`?


================
Comment at: llvm/lib/Support/raw_ostream.cpp:755-780
+#if defined(_WIN32)
+  // Disable buffering for console devices. Console output is re-encoded from
+  // UTF-8 to UTF-16 on Windows, and buffering it would require us to split the
+  // buffer on a valid UTF-8 codepoint boundary. Terminal buffering is disabled
+  // below on most other OSs, so do the same thing on Windows and avoid that
+  // complexity.
+  if (IsConsole)
----------------
Given that we already have this `IsConsole` variable, combined with my suggestion above to set the variable to a real value for every platform, can we re-write this entire function:

```
if (IsConsole)
  return 0;

#if !defined(__minix)
  struct stat statbuf;
  if (fstat(FD, &statbuf) != 0)
    return 0;
  return statbuf.st_blksize.
#else
  return raw_ostream::preferred_buffer_size();
#endif
```


https://reviews.llvm.org/D51558