/* $Id$
 *
 * gdb2 - gdb output splitter
 *
 * Copyright (C) 2000,2001 Nedko Arnaoudov <nedkohome@atia.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 */

#include "ph.h"

#define GDB_INITIAL_COMMAND "gdb.exe"
#define PARAMS_SEPARATOR " "
#define PARAMS_SEPARATOR_LEN strlen(PARAMS_SEPARATOR);

void DisplayError(char *pszAPI);
void ReadAndHandleOutput(HANDLE hPipeRead);
void PrepAndLaunchRedirectedChild(HANDLE hChildStdOut,
								  HANDLE hChildStdIn,
								  HANDLE hChildStdErr,
								  char *pchCommandLine);

DWORD WINAPI GetAndSendInputThread(LPVOID lpvThreadParam);
HANDLE hChildProcess = NULL;
HANDLE hStdIn = NULL; // Handle to parents std input.
BOOL bRunThread = TRUE;

int main(int argc, char* argv[])
{
	HANDLE hOutputReadTmp,hOutputRead,hOutputWrite;
	HANDLE hInputWriteTmp,hInputRead,hInputWrite;
	HANDLE hErrorWrite;
	HANDLE hThread;
	DWORD ThreadId;
	SECURITY_ATTRIBUTES sa;

	// Set up the security attributes struct.
	sa.nLength= sizeof(SECURITY_ATTRIBUTES);
	sa.lpSecurityDescriptor = NULL;
	sa.bInheritHandle = TRUE;


	// Create the child output pipe.
	if (!CreatePipe(&hOutputReadTmp,&hOutputWrite,&sa,0))
		DisplayError("CreatePipe");


	// Create a duplicate of the output write handle for the std error
	// write handle. This is necessary in case the child application
	// closes one of its std output handles.
	if (!DuplicateHandle(GetCurrentProcess(),hOutputWrite,
		GetCurrentProcess(),&hErrorWrite,0,
		TRUE,DUPLICATE_SAME_ACCESS))
		DisplayError("DuplicateHandle");


	// Create the child input pipe.
	if (!CreatePipe(&hInputRead,&hInputWriteTmp,&sa,0))
		DisplayError("CreatePipe");


	// Create new output read handle and the input write handles. Set
	// the Properties to FALSE. Otherwise, the child inherits the
	// properties and, as a result, non-closeable handles to the pipes
	// are created.
	if (!DuplicateHandle(GetCurrentProcess(),hOutputReadTmp,
		GetCurrentProcess(),
		&hOutputRead, // Address of new handle.
		0,FALSE, // Make it uninheritable.
		DUPLICATE_SAME_ACCESS))
		DisplayError("DupliateHandle");

	if (!DuplicateHandle(GetCurrentProcess(),hInputWriteTmp,
		GetCurrentProcess(),
		&hInputWrite, // Address of new handle.
		0,FALSE, // Make it uninheritable.
		DUPLICATE_SAME_ACCESS))
		DisplayError("DupliateHandle");


	// Close inheritable copies of the handles you do not want to be
	// inherited.
	if (!CloseHandle(hOutputReadTmp)) DisplayError("CloseHandle");
	if (!CloseHandle(hInputWriteTmp)) DisplayError("CloseHandle");


	// Get std input handle so you can close it and force the ReadFile to
	// fail when you want the input thread to exit.
	if ( (hStdIn = GetStdHandle(STD_INPUT_HANDLE)) ==
		INVALID_HANDLE_VALUE )
		DisplayError("GetStdHandle");

	SetConsoleTitle("gdb control console");

	size_t size = strlen(GDB_INITIAL_COMMAND)+PARAMS_SEPARATOR_LEN;

	// get parameters length
	for (int i = 1 ; i < argc ; i++)
		size += strlen(argv[i])+PARAMS_SEPARATOR_LEN;

	size++; // terminating null

	char *pszCommandLine = new char [size];
	if (!pszCommandLine)
	{
		printf("out of memory.\n");
		return -1;
	}

	strcpy(pszCommandLine,GDB_INITIAL_COMMAND);
	for (int i = 1 ; i < argc ; i++)
	{
		strcat(pszCommandLine,PARAMS_SEPARATOR);
		strcat(pszCommandLine,argv[i]);
	}

	PrepAndLaunchRedirectedChild(hOutputWrite,hInputRead,hErrorWrite,pszCommandLine);


	// Close pipe handles (do not continue to modify the parent).
	// You need to make sure that no handles to the write end of the
	// output pipe are maintained in this process or else the pipe will
	// not close when the child process exits and the ReadFile will hang.
	if (!CloseHandle(hOutputWrite)) DisplayError("CloseHandle");
	if (!CloseHandle(hInputRead )) DisplayError("CloseHandle");
	if (!CloseHandle(hErrorWrite)) DisplayError("CloseHandle");


	// Launch the thread that gets the input and sends it to the child.
	hThread = CreateThread(NULL,0,GetAndSendInputThread,
		(LPVOID)hInputWrite,0,&ThreadId);
	if (hThread == NULL) DisplayError("CreateThread");


	// Read the child's output.
	ReadAndHandleOutput(hOutputRead);
	// Redirection is complete


	// Force the read on the input to return by closing the stdin handle.
	if (!CloseHandle(hStdIn)) DisplayError("CloseHandle");


	// Tell the thread to exit and wait for thread to die.
	bRunThread = FALSE;

	if (WaitForSingleObject(hThread,INFINITE) == WAIT_FAILED)
		DisplayError("WaitForSingleObject");

	if (!CloseHandle(hOutputRead)) DisplayError("CloseHandle");
	if (!CloseHandle(hInputWrite)) DisplayError("CloseHandle");

	return 0;
}

///////////////////////////////////////////////////////////////////////
// PrepAndLaunchRedirectedChild
// Sets up STARTUPINFO structure, and launches redirected child.
///////////////////////////////////////////////////////////////////////
void PrepAndLaunchRedirectedChild(HANDLE hChildStdOut,
								  HANDLE hChildStdIn,
								  HANDLE hChildStdErr,
								  char *pchCommandLine)
{
	PROCESS_INFORMATION pi;
	STARTUPINFO si;

	// Set up the start up info struct.
	ZeroMemory(&si,sizeof(STARTUPINFO));
	si.cb = sizeof(STARTUPINFO);
	si.dwFlags = STARTF_USESTDHANDLES;
	si.hStdOutput = hChildStdOut;
	si.hStdInput  = hChildStdIn;
	si.hStdError  = hChildStdErr;
	si.lpTitle = "debugged program console";
	// Use this if you want to hide the child:
	//     si.wShowWindow = SW_HIDE;
	// Note that dwFlags must include STARTF_USESHOWWINDOW if you want to
	// use the wShowWindow flags.


	// Launch the process that you want to redirect (in this case,
	// Child.exe). Make sure Child.exe is in the same directory as
	// redirect.c launch redirect from a command line to prevent location
	// confusion.
	if (!CreateProcess(NULL,pchCommandLine,NULL,NULL,TRUE,
		CREATE_NEW_CONSOLE,NULL,NULL,&si,&pi))
		DisplayError("CreateProcess");


	// Set global child process handle to cause threads to exit.
	hChildProcess = pi.hProcess;


	// Close any unnecessary handles.
	if (!CloseHandle(pi.hThread)) DisplayError("CloseHandle");
}

///////////////////////////////////////////////////////////////////////
// ReadAndHandleOutput
// Monitors handle for input. Exits when child exits or pipe breaks.
///////////////////////////////////////////////////////////////////////
void ReadAndHandleOutput(HANDLE hPipeRead)
{
	CHAR lpBuffer[256];
	DWORD nBytesRead;
	DWORD nCharsWritten;

	while(TRUE)
	{
		if (!ReadFile(hPipeRead,lpBuffer,sizeof(lpBuffer),
			&nBytesRead,NULL) || !nBytesRead)
		{
            if (GetLastError() == ERROR_BROKEN_PIPE)
				break; // pipe done - normal exit path.
            else
				DisplayError("ReadFile"); // Something bad happened.
		}

		// Display the character read on the screen.
		if (!WriteConsole(GetStdHandle(STD_OUTPUT_HANDLE),lpBuffer,
			nBytesRead,&nCharsWritten,NULL))
            DisplayError("WriteConsole");
	}
}


///////////////////////////////////////////////////////////////////////
// GetAndSendInputThread
// Thread procedure that monitors the console for input and sends input
// to the child process through the input pipe.
// This thread ends when the child application exits.
///////////////////////////////////////////////////////////////////////
DWORD WINAPI GetAndSendInputThread(LPVOID lpvThreadParam)
{
	CHAR read_buff[256];
	DWORD nBytesRead,nBytesWrote;
	HANDLE hPipeWrite = (HANDLE)lpvThreadParam;

	// Get input from our console and send it to child through the pipe.
	while (bRunThread)
	{
		if(!ReadConsole(hStdIn,read_buff,1,&nBytesRead,NULL))
            DisplayError("ReadConsole");

		read_buff[nBytesRead] = '\0'; // Follow input with a NULL.

		if (!WriteFile(hPipeWrite,read_buff,nBytesRead,&nBytesWrote,NULL))
		{
            if (GetLastError() == ERROR_NO_DATA)
				break; // Pipe was closed (normal exit path).
            else
				DisplayError("WriteFile");
		}
	}

	return 1;
}

///////////////////////////////////////////////////////////////////////
// DisplayError
// Displays the error number and corresponding message.
///////////////////////////////////////////////////////////////////////
void DisplayError(char *pszAPI)
{
	LPVOID lpvMessageBuffer;
	CHAR szPrintBuffer[512];
	DWORD nCharsWritten;

	FormatMessage(
		FORMAT_MESSAGE_ALLOCATE_BUFFER|FORMAT_MESSAGE_FROM_SYSTEM,
		NULL, GetLastError(),
		MAKELANGID(LANG_NEUTRAL, SUBLANG_DEFAULT),
		(LPTSTR)&lpvMessageBuffer, 0, NULL);

	wsprintf(szPrintBuffer,
		"ERROR: API    = %s.\n   error code = %d.\n   message    = %s.\n",
		pszAPI, GetLastError(), (char *)lpvMessageBuffer);

	WriteConsole(GetStdHandle(STD_OUTPUT_HANDLE),szPrintBuffer,
		lstrlen(szPrintBuffer),&nCharsWritten,NULL);

	LocalFree(lpvMessageBuffer);
	ExitProcess(GetLastError());
}