Subsystem.h

/*
 * Copyright (c) 2008-2014, Pedigree Developers
 *
 * Please see the CONTRIB file in the root of the source tree for a full
 * list of contributors.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 */

#ifndef SUBSYSTEM_H
#define SUBSYSTEM_H

#include "pedigree/kernel/Log.h"
#include "pedigree/kernel/compiler.h"
#include "pedigree/kernel/processor/state_forward.h"
#include "pedigree/kernel/utilities/String.h"

class File;
class Process;
class Thread;
template <class T>
class Vector;

class EXPORTED_PUBLIC Subsystem
{
    friend class Process;

  public:
    enum SubsystemType
    {
        Posix = 0,
        Native = 1,
        None = 255
    };

    enum KillReason
    {
        Interrupted = 0,
        Terminated = 1,
        Unknown = 255
    };

    enum ExceptionType
    {
        InvalidOpcode = 0,
        PageFault = 1,
        GeneralProtectionFault = 2,
        DivideByZero = 3,
        FpuError = 4,
        SpecialFpuError = 5,
        TerminalInput = 6,   // Read from terminal, but not foreground.
        TerminalOutput = 7,  // Output to terminal, but not foreground.
        Continue = 8,
        Stop = 9,
        Interrupt = 10,
        Quit = 11,
        Child = 12,  // Child pause/continue/quit.
        Pipe = 13,   // Pipe broken.
        Other = 255
    };

    Subsystem() : m_Type(None), m_pProcess(0)
    {
    }

    Subsystem(const Subsystem &s) : m_Type(s.m_Type), m_pProcess(0)
    {
    }

    Subsystem(SubsystemType type) : m_Type(type), m_pProcess(0)
    {
    }

    virtual ~Subsystem();

    virtual void acquire();

    virtual void release();

    virtual void exit(int code) = 0;

    virtual bool kill(KillReason killReason, Thread *pThread = 0) = 0;

    virtual void threadException(Thread *pThread, ExceptionType eType);

    SubsystemType getType()
    {
        return m_Type;
    }

    virtual void setProcess(Process *p)
    {
        if ((!m_pProcess) | (m_pProcess == p))
            m_pProcess = p;
        else
            WARNING(
                "An attempt was made to change the Process of a Subsystem!");
    }

    virtual bool
    invoke(const char *name, Vector<String> &argv, Vector<String> &env) = 0;

    virtual bool invoke(
        const char *name, Vector<String> &argv, Vector<String> &env,
        SyscallState &state) = 0;

    virtual bool invoke(
        File *originalFile, const String &originalName, Vector<String> &argv,
        Vector<String> &env) = 0;

    virtual bool invoke(
        File *originalFile, const String &originalName, Vector<String> &argv,
        Vector<String> &env, SyscallState &state) = 0;

    virtual File *findFile(const String &path, File *workingDir) = 0;

  protected:
    virtual void threadRemoved(Thread *pThread)
    {
    }

    SubsystemType m_Type;

    Process *m_pProcess;

  private:
    const Subsystem &operator=(const Subsystem &);
};

#endif