From f490bec4a1356a0d3f8269eae5cb2c7cbcd3174e Mon Sep 17 00:00:00 2001
From: Zachary Turner <zturner@google.com>
Date: Mon, 4 Aug 2014 23:31:21 +0000
Subject: [PATCH] Teach ProcessWindows plugin to support stdio i/o redirection.

llvm-svn: 214816
---
 .../Plugins/Process/Windows/ProcessWindows.cpp     | 72 ++++++++++++++++++----
 1 file changed, 61 insertions(+), 11 deletions(-)

diff --git a/lldb/source/Plugins/Process/Windows/ProcessWindows.cpp b/lldb/source/Plugins/Process/Windows/ProcessWindows.cpp
index 8aeed4b..d421025 100644
--- a/lldb/source/Plugins/Process/Windows/ProcessWindows.cpp
+++ b/lldb/source/Plugins/Process/Windows/ProcessWindows.cpp
@@ -25,6 +25,42 @@
 using namespace lldb;
 using namespace lldb_private;
 
+namespace
+{
+HANDLE
+GetStdioHandle(ProcessLaunchInfo &launch_info, int fd)
+{
+    const ProcessLaunchInfo::FileAction *action = launch_info.GetFileActionForFD(fd);
+    if (action == nullptr)
+        return NULL;
+    SECURITY_ATTRIBUTES secattr = {0};
+    secattr.nLength = sizeof(SECURITY_ATTRIBUTES);
+    secattr.bInheritHandle = TRUE;
+
+    const char *path = action->GetPath();
+    DWORD access = 0;
+    DWORD share = FILE_SHARE_READ | FILE_SHARE_WRITE;
+    DWORD create = 0;
+    DWORD flags = 0;
+    if (fd == STDIN_FILENO)
+    {
+        access = GENERIC_READ;
+        create = OPEN_EXISTING;
+        flags = FILE_ATTRIBUTE_READONLY;
+    }
+    if (fd == STDOUT_FILENO || fd == STDERR_FILENO)
+    {
+        access = GENERIC_WRITE;
+        create = CREATE_ALWAYS;
+        if (fd == STDERR_FILENO)
+            flags = FILE_FLAG_WRITE_THROUGH;
+    }
+
+    HANDLE result = ::CreateFile(path, access, share, &secattr, create, flags, NULL);
+    return (result == INVALID_HANDLE_VALUE) ? NULL : result;
+}
+}
+
 //------------------------------------------------------------------------------
 // Static functions.
 
@@ -91,20 +127,34 @@ ProcessWindows::DoLaunch(Module *exe_module,
     std::vector<char> environment;
     STARTUPINFO startupinfo = {0};
     PROCESS_INFORMATION pi = {0};
+
+    HANDLE stdin_handle = GetStdioHandle(launch_info, STDIN_FILENO);
+    HANDLE stdout_handle = GetStdioHandle(launch_info, STDOUT_FILENO);
+    HANDLE stderr_handle = GetStdioHandle(launch_info, STDERR_FILENO);
+
     startupinfo.cb = sizeof(startupinfo);
-    
+    startupinfo.dwFlags |= STARTF_USESTDHANDLES;
+    startupinfo.hStdError = stderr_handle;
+    startupinfo.hStdInput = stdin_handle;
+    startupinfo.hStdOutput = stdout_handle;
+
     executable = launch_info.GetExecutableFile().GetPath();
     launch_info.GetArguments().GetQuotedCommandString(commandLine);
-    BOOL result = ::CreateProcessA(executable.c_str(),
-                                   const_cast<char*>(commandLine.c_str()),
-                                   NULL,
-                                   NULL,
-                                   FALSE,
-                                   CREATE_NEW_CONSOLE,
-                                   NULL,
-                                   launch_info.GetWorkingDirectory(),
-                                   &startupinfo,
-                                   &pi);
+    BOOL result = ::CreateProcessA(executable.c_str(), const_cast<char *>(commandLine.c_str()), NULL, NULL, TRUE,
+                                   CREATE_NEW_CONSOLE, NULL, launch_info.GetWorkingDirectory(), &startupinfo, &pi);
+    if (result)
+    {
+        ::CloseHandle(pi.hProcess);
+        ::CloseHandle(pi.hThread);
+    }
+
+    if (stdin_handle)
+        ::CloseHandle(stdin_handle);
+    if (stdout_handle)
+        ::CloseHandle(stdout_handle);
+    if (stderr_handle)
+        ::CloseHandle(stderr_handle);
+
     Error error;
     if (!result)
         error.SetErrorToErrno();
-- 
2.7.4