Fix deadlock in Python one-line execution.

Python one-line execution was using ConnectionFileDescriptor to do
a non-blocking read against a pipe.  This won't work on Windows,
as CFD is implemented using select(), and select() only works with
sockets on Windows.

The solution is to use ConnectionGenericFile on Windows, which uses
the native API to do overlapped I/O on the pipe.  This in turn
requires re-implementing Host::Pipe on Windows using native OS
handles instead of the more portable _pipe CRT api.

Reviewed by: Greg Clayton
Differential Revision: http://reviews.llvm.org/D5679

llvm-svn: 219339

1 files changed, 10 insertions, 3 deletions

diff --git a/lldb/source/Host/windows/ConnectionGenericFileWindows.cpp b/lldb/source/Host/windows/ConnectionGenericFileWindows.cpp
index 312cef62d65..93d37945992 100644
--- a/lldb/source/Host/windows/ConnectionGenericFileWindows.cpp
+++ b/lldb/source/Host/windows/ConnectionGenericFileWindows.cpp
@@ -241,9 +241,16 @@ ConnectionGenericFile::Read(void *dst, size_t dst_len, uint32_t timeout_usec, ll
 
         goto finish;
     }
-
-    // An unknown error occured.  Fail out.
-    return_info.Set(0, eConnectionStatusError, ::GetLastError());
+    else if (::GetLastError() == ERROR_BROKEN_PIPE)
+    {
+        // The write end of a pipe was closed.  This is equivalent to EOF.
+        return_info.Set(0, eConnectionStatusEndOfFile, 0);
+    }
+    else
+    {
+        // An unknown error occured.  Fail out.
+        return_info.Set(0, eConnectionStatusError, ::GetLastError());
+    }
     goto finish;
 
 finish: