unix: read on stream even when UV__POLLHUP set.

This fixes a SmartOS specific issue that happens when reading from
a stream that is the reading end of a pipe that has been closed by
the parent process.

In this case, a UV__POLLHUP event would be set on the stream and would
prevent the event loop from closing it. As a result, the event loop
would think there are stil handles open, and leave the process
hanging.

Fixes #1419.

Makefile.am

@@ -163,6 +163,7 @@ test_run_tests_SOURCES = test/blackhole-server.c \
                          test/test-pipe-getsockname.c \
                          test/test-pipe-sendmsg.c \
                          test/test-pipe-server-close.c \
+                         test/test-pipe-close-stdout-read-stdin.c \
                          test/test-platform-output.c \
                          test/test-poll-close.c \
                          test/test-poll-closesocket.c \

src/unix/stream.c

@@ -1162,7 +1162,7 @@ static void uv__stream_io(uv_loop_t* loop, uv__io_t* w, unsigned int events) {
   assert(uv__stream_fd(stream) >= 0);
 
   /* Ignore POLLHUP here. Even it it's set, there may still be data to read. */
-  if (events & (UV__POLLIN | UV__POLLERR))
+  if (events & (UV__POLLIN | UV__POLLERR | UV__POLLHUP))
     uv__read(stream);
 
   if (uv__stream_fd(stream) == -1)

test/test-list.h

@@ -156,6 +156,9 @@ TEST_DECLARE   (pipe_ref)
 TEST_DECLARE   (pipe_ref2)
 TEST_DECLARE   (pipe_ref3)
 TEST_DECLARE   (pipe_ref4)
+#ifndef _WIN32
+TEST_DECLARE   (pipe_close_stdout_read_stdin)
+#endif
 TEST_DECLARE   (process_ref)
 TEST_DECLARE   (has_ref)
 TEST_DECLARE   (active)
@@ -314,6 +317,9 @@ TASK_LIST_START
   TEST_ENTRY  (pipe_connect_to_file)
 
   TEST_ENTRY  (pipe_server_close)
+#ifndef _WIN32
+  TEST_ENTRY  (pipe_close_stdout_read_stdin)
+#endif
   TEST_ENTRY  (tty)
   TEST_ENTRY  (stdio_over_pipes)
   TEST_ENTRY  (ip6_pton)

test/test-pipe-close-stdout-read-stdin.c

@@ -0,0 +1,103 @@
+/* Copyright Joyent, Inc. and other Node contributors. All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to
+ * deal in the Software without restriction, including without limitation the
+ * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
+ * sell copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#ifndef _WIN32
+
+#include <stdlib.h>
+#include <unistd.h>
+#include <sys/wait.h>
+#include <sys/types.h>
+
+#include "uv.h"
+#include "task.h"
+
+void alloc_buffer(uv_handle_t *handle, size_t suggested_size, uv_buf_t* buf)
+{
+  static char buffer[1024];
+
+  buf->base = buffer;
+  buf->len = sizeof(buffer);
+}
+
+void read_stdin(uv_stream_t *stream, ssize_t nread, const uv_buf_t* buf)
+{
+  if (nread < 0) {
+    uv_close((uv_handle_t*)stream, NULL);
+    return;
+  }
+}
+
+/*
+ * This test is a reproduction of joyent/libuv#1419 .
+ */
+TEST_IMPL(pipe_close_stdout_read_stdin) {
+  int r = -1;
+  int pid;
+  int fd[2];
+  int status;
+
+  pipe(fd);
+
+  if ((pid = fork()) == 0) {
+    /*
+     * Make the read side of the pipe our stdin.
+     * The write side will be closed by the parent process.
+    */
+    close(fd[1]);
+    close(0);
+    dup(fd[0]);
+
+    /* Create a stream that reads from the pipe. */
+    uv_pipe_t stdin_pipe;
+
+    r = uv_pipe_init(uv_default_loop(), (uv_pipe_t *)&stdin_pipe, 0);
+    ASSERT(r == 0);
+
+    r = uv_pipe_open((uv_pipe_t *)&stdin_pipe, 0);
+    ASSERT(r == 0);
+
+    r = uv_read_start((uv_stream_t *)&stdin_pipe, alloc_buffer, read_stdin);
+    ASSERT(r == 0);
+
+    /*
+     * Because the other end of the pipe was closed, there should
+     * be no event left to process after one run of the event loop.
+     * Otherwise, it means that events were not processed correctly.
+     */
+    ASSERT(uv_run(uv_default_loop(), UV_RUN_NOWAIT) == 0);
+  } else {
+    /*
+     * Close both ends of the pipe so that the child
+     * get a POLLHUP event when it tries to read from
+     * the other end.
+     */
+     close(fd[1]);
+     close(fd[0]);
+
+    waitpid(pid, &status, 0);
+    ASSERT(WIFEXITED(status) && WEXITSTATUS(status) == 0);
+  }
+
+  MAKE_VALGRIND_HAPPY();
+  return 0;
+}
+
+#endif /* ifndef _WIN32 */

uv.gyp

@@ -346,6 +346,7 @@
         'test/test-pipe-getsockname.c',
         'test/test-pipe-sendmsg.c',
         'test/test-pipe-server-close.c',
+        'test/test-pipe-close-stdout-read-stdin.c',
         'test/test-platform-output.c',
         'test/test-poll.c',
         'test/test-poll-close.c',