From 40b552be4a2b81b87b9b87155aaa3c70d3ce62a8 Mon Sep 17 00:00:00 2001
From: Peter Johnson <johnson.peter@gmail.com>
Date: Sun, 17 Sep 2023 20:01:24 -0700
Subject: [PATCH] [wpinet] uv::Stream: Return error from TryWrite() (#5655)

---
 wpinet/src/main/native/cpp/uv/Stream.cpp          |  8 ++++----
 wpinet/src/main/native/include/wpinet/uv/Stream.h | 12 ++++++++----
 2 files changed, 12 insertions(+), 8 deletions(-)

diff --git a/wpinet/src/main/native/cpp/uv/Stream.cpp b/wpinet/src/main/native/cpp/uv/Stream.cpp
index 2891aaeeb8..fdceb7b1f2 100644
--- a/wpinet/src/main/native/cpp/uv/Stream.cpp
+++ b/wpinet/src/main/native/cpp/uv/Stream.cpp
@@ -111,25 +111,25 @@ void Stream::Write(std::span<const Buffer> bufs,
 
 int Stream::TryWrite(std::span<const Buffer> bufs) {
   if (IsLoopClosing()) {
-    return 0;
+    return UV_ECANCELED;
   }
   int val = uv_try_write(GetRawStream(), bufs.data(), bufs.size());
   if (val < 0) {
     this->ReportError(val);
-    return 0;
+    return val;
   }
   return val;
 }
 
 int Stream::TryWrite2(std::span<const Buffer> bufs, Stream& send) {
   if (IsLoopClosing()) {
-    return 0;
+    return UV_ECANCELED;
   }
   int val = uv_try_write2(GetRawStream(), bufs.data(), bufs.size(),
                           send.GetRawStream());
   if (val < 0) {
     this->ReportError(val);
-    return 0;
+    return val;
   }
   return val;
 }
diff --git a/wpinet/src/main/native/include/wpinet/uv/Stream.h b/wpinet/src/main/native/include/wpinet/uv/Stream.h
index 9568455512..29e58118a6 100644
--- a/wpinet/src/main/native/include/wpinet/uv/Stream.h
+++ b/wpinet/src/main/native/include/wpinet/uv/Stream.h
@@ -194,8 +194,9 @@ class Stream : public Handle {
    * An error signal will be emitted in case of errors.
    *
    * @param bufs The buffers to be written to the stream.
-   * @return Number of bytes written.
+   * @return Number of bytes written, or negative (error code) on error
    */
+  [[nodiscard]]
   int TryWrite(std::span<const Buffer> bufs);
 
   /**
@@ -206,8 +207,9 @@ class Stream : public Handle {
    * An error signal will be emitted in case of errors.
    *
    * @param bufs The buffers to be written to the stream.
-   * @return Number of bytes written.
+   * @return Number of bytes written, or negative (error code) on error
    */
+  [[nodiscard]]
   int TryWrite(std::initializer_list<Buffer> bufs) {
     return TryWrite({bufs.begin(), bufs.end()});
   }
@@ -221,8 +223,9 @@ class Stream : public Handle {
    *
    * @param bufs The buffers to be written to the stream.
    * @param send send stream
-   * @return Number of bytes written.
+   * @return Number of bytes written, or negative (error code) on error
    */
+  [[nodiscard]]
   int TryWrite2(std::span<const Buffer> bufs, Stream& send);
 
   /**
@@ -234,8 +237,9 @@ class Stream : public Handle {
    *
    * @param bufs The buffers to be written to the stream.
    * @param send send stream
-   * @return Number of bytes written.
+   * @return Number of bytes written, or negative (error code) on error
    */
+  [[nodiscard]]
   int TryWrite2(std::initializer_list<Buffer> bufs, Stream& send) {
     return TryWrite2({bufs.begin(), bufs.end()}, send);
   }