From 5cdc7c2c5343fe3c47ea75207b978288ae8f6a3f Mon Sep 17 00:00:00 2001
From: Arseny Smirnov <arseny30@gmail.com>
Date: Tue, 11 Sep 2018 17:48:29 +0300
Subject: [PATCH] BufferedStdin: simplify

GitOrigin-RevId: 8674573bea8246cf2e5c21bbdaae98712d8c7cc4
---
 tdutils/td/utils/port/StdStreams.cpp | 41 ++++++++++++++++++----------
 1 file changed, 26 insertions(+), 15 deletions(-)

diff --git a/tdutils/td/utils/port/StdStreams.cpp b/tdutils/td/utils/port/StdStreams.cpp
index c220170e..909dd343 100644
--- a/tdutils/td/utils/port/StdStreams.cpp
+++ b/tdutils/td/utils/port/StdStreams.cpp
@@ -51,9 +51,7 @@ FileFd &Stderr() {
 namespace detail {
 class BufferedStdinImpl {
  public:
-  BufferedStdinImpl() {
-    file_fd_ = FileFd::from_native_fd(NativeFd(Stdin().get_native_fd().fd()));
-    copy_file_fd_ = FileFd::from_native_fd(NativeFd(Stdin().get_native_fd().fd()));
+  BufferedStdinImpl() : info_(NativeFd(GetStdHandle(STD_INPUT_HANDLE), true)) {
     read_thread_ = td::thread([this] { this->read_loop(); });
   }
   BufferedStdinImpl(const BufferedStdinImpl &) = delete;
@@ -61,8 +59,7 @@ class BufferedStdinImpl {
   BufferedStdinImpl(BufferedStdinImpl &&) = delete;
   BufferedStdinImpl &operator=(BufferedStdinImpl &&) = delete;
   ~BufferedStdinImpl() {
-    file_fd_.move_as_native_fd().release();
-    copy_file_fd_.move_as_native_fd().release();
+    info_.move_as_native_fd().release();
   }
   void close() {
     close_flag_ = true;
@@ -73,37 +70,51 @@ class BufferedStdinImpl {
   }
 
   PollableFdInfo &get_poll_info() {
-    return file_fd_.get_poll_info();
+    return info_;
   }
   const PollableFdInfo &get_poll_info() const {
-    return file_fd_.get_poll_info();
+    return info_;
   }
 
   Result<size_t> flush_read(size_t max_read = std::numeric_limits<size_t>::max()) TD_WARN_UNUSED_RESULT {
-    file_fd_.get_poll_info().get_flags();
-    file_fd_.get_poll_info().clear_flags(PollFlags::Read());
+    info_.get_flags();
+    info_.clear_flags(PollFlags::Read());
     reader_.sync_with_writer();
     return reader_.size();
   }
 
  private:
-  FileFd file_fd_;
-  FileFd copy_file_fd_;
+  PollableFdInfo info_;
   ChainBufferWriter writer_;
   ChainBufferReader reader_ = writer_.extract_reader();
   td::thread read_thread_;
-
   std::atomic<bool> close_flag_{false};
 
+
   void read_loop() {
     while (!close_flag_) {
       auto slice = writer_.prepare_append();
-      auto size = copy_file_fd_.read(slice).move_as_ok();
-      writer_.confirm_append(size);
-      file_fd_.get_poll_info().add_flags_from_poll(td::PollFlags::Read());
+      auto r_size = read(slice);
+      if (r_size.is_error()) {
+        LOG(ERROR) << "Stop read stdin loop: " << r_size.error();
+        break;
+      }
+      writer_.confirm_append(r_size.ok());
+      info_.add_flags_from_poll(td::PollFlags::Read());
     }
     //TODO delete
   }
+
+  Result<size_t> read(MutableSlice slice) {
+    auto native_fd = info_.native_fd().io_handle();
+    DWORD bytes_read = 0;
+    auto res = ReadFile(native_fd, slice.data(), narrow_cast<DWORD>(slice.size()), &bytes_read, nullptr);
+    if (res) {
+      return static_cast<size_t>(bytes_read);
+    }
+    return OS_ERROR(PSLICE() << "Read from [fd = " << native_fd << "] has failed");
+  }
+
 };
 void BufferedStdinImplDeleter::operator()(BufferedStdinImpl *impl) {
   impl->close();