//===-- MIDriverMain.cpp ----------------------------------------*- C++ -*-===//
//
//                     The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//

// Overview:    Defines the entry point for the console application.
//              The MI application (project name MI) runs in two modes:
//              An LLDB native driver mode where it acts no different from the LLDB driver.
//              The other mode is the MI when it finds on the command line
//              the --interpreter option. Command line argument --help on its own will give
//              help for the LLDB driver. If entered with --interpreter then MI help will
//              provided.
//              To implement new MI commands derive a new command class from the command base
//              class. To enable the new command for interpretation add the new command class
//              to the command factory. The files of relevance are:
//                  MICmdCommands.cpp
//                  MICmdBase.h / .cpp
//                  MICmdCmd.h / .cpp


#if defined(_MSC_VER)
#define _INC_SIGNAL // Stop window's signal.h being included - CODETAG_IOR_SIGNALS
#endif              // _MSC_VER

// Third party headers:
#include <stdio.h>
#include "lldb/API/SBHostOS.h"

// In house headers:
#include "MICmnConfig.h"
#include "Platform.h" // Define signals - CODETAG_IOR_SIGNALS
#include "MIDriverMgr.h"
#include "MIDriver.h"
#include "MICmnResources.h"
#include "MICmnStreamStdin.h"
#include "MIUtilDebug.h"


#if defined(_MSC_VER)
#pragma warning(once : 4530) // Warning C4530: C++ exception handler used, but unwind semantics are not enabled. Specify /EHsc
#endif                       // _MSC_VER

// CODETAG_IOR_SIGNALS
//++ ------------------------------------------------------------------------------------
// Details: The SIGINT signal is sent to a process by its controlling terminal when a
//          user wishes to interrupt the process. This is typically initiated by pressing
//          Control-C, but on some systems, the "delete" character or "break" key can be
//          used.
//          Be aware this function may be called on another thread besides the main thread.
// Type:    Function.
// Args:    vSigno  - (R) Signal number.
// Return:  None.
// Throws:  None.
//--
void
sigint_handler(int vSigno)
{
#ifdef _WIN32 // Restore handler as it is not persistent on Windows
    signal(SIGINT, sigint_handler);
#endif
    static bool g_interrupt_sent = false;
    CMIDriverMgr &rDriverMgr = CMIDriverMgr::Instance();
    lldb::SBDebugger *pDebugger = rDriverMgr.DriverGetTheDebugger();
    if (pDebugger != nullptr)
    {
        if (!g_interrupt_sent)
        {
            g_interrupt_sent = true;
            pDebugger->DispatchInputInterrupt();
            g_interrupt_sent = false;
        }
    }

    // Send signal to driver so that it can take suitable action
    rDriverMgr.DeliverSignal (vSigno);
}

//++ ------------------------------------------------------------------------------------
// Details: Init the MI driver system. Initialize the whole driver system which includes
//          both the original LLDB driver and the MI driver.
// Type:    Function.
// Args:    None.
// Return:  MIstatus::success - Functional succeeded.
//          MIstatus::failure - Functional failed.
// Throws:  None.
//--
bool
DriverSystemInit(void)
{
    bool bOk = MIstatus::success;
    CMIDriver &rMIDriver = CMIDriver::Instance();
    CMIDriverMgr &rDriverMgr = CMIDriverMgr::Instance();
    bOk = rDriverMgr.Initialize();

    // Register MIDriver first as it needs to initialize and be ready
    // for the Driver to get information from MIDriver when it initializes
    // (LLDB Driver is registered with the Driver Manager in MI's Initialize())
    bOk = bOk && rDriverMgr.RegisterDriver(rMIDriver, "MIDriver"); // Will be main driver

    return bOk;
}

//++ ------------------------------------------------------------------------------------
// Details: Shutdown the debugger system. Release / terminate resources external to
//          specifically the MI driver.
// Type:    Function.
// Args:    vbAppExitOk - (R) True = No problems, false = App exiting with problems (investigate!).
// Return:  MIstatus::success - Functional succeeded.
//          MIstatus::failure - Functional failed.
// Throws:  None.
//--
bool
DriverSystemShutdown(const bool vbAppExitOk)
{
    bool bOk = MIstatus::success;

    // *** Order is important here ***
    CMIDriverMgr::Instance().Shutdown();
    return bOk;
}

//++ ------------------------------------------------------------------------------------
// Details: MI's application start point of execution. The application runs in two modes.
//          An LLDB native driver mode where it acts no different from the LLDB driver.
//          The other mode is the MI when it finds on the command line
//          the --interpreter option. Command line argument --help on its own will give
//          help for the LLDB driver. If entered with --interpreter then application
//          help will provided.
// Type:    Method.
// Args:    argc    - (R) An integer that contains the count of arguments that follow in
//                        argv. The argc parameter is always greater than or equal to 1.
//          argv    - (R) An array of null-terminated strings representing command-line
//                        arguments entered by the user of the program. By convention,
//                        argv[0] is the command with which the program is invoked.
// Return:  int -  0 =   Normal exit, program success.
//                >0    = Program success with status i.e. Control-C signal status
//                <0    = Program failed.
//              -1      = Program failed reason not specified here, see MI log file.
//              -1000   = Program failed did not initialize successfully.
// Throws:  None.
//--
int
main(int argc, char const *argv[])
{
#if MICONFIG_DEBUG_SHOW_ATTACH_DBG_DLG
#ifdef _WIN32
    CMIUtilDebug::ShowDlgWaitForDbgAttach();
#else
    CMIUtilDebug::WaitForDbgAttachInfinteLoop();
#endif //  _WIN32
#endif // MICONFIG_DEBUG_SHOW_ATTACH_DBG_DLG

    // *** Order is important here ***
    bool bOk = DriverSystemInit();
    if (!bOk)
    {
        DriverSystemShutdown(bOk);
        return -1000;
    }

    // CODETAG_IOR_SIGNALS
    signal(SIGINT, sigint_handler);

    bool bExiting = false;
    CMIDriverMgr &rDriverMgr = CMIDriverMgr::Instance();
    bOk = bOk && rDriverMgr.ParseArgs(argc, argv, bExiting);
    if (bOk && !bExiting)
        bOk = rDriverMgr.DriverParseArgs(argc, argv, stdout, bExiting);
    if (bOk && !bExiting)
        bOk = rDriverMgr.DriverMainLoop();

    // Logger and other resources shutdown now
    DriverSystemShutdown(bOk);

    const int appResult = bOk ? 0 : -1;

    return appResult;
}