source: vbox/trunk/include/VBox/HostServices/GuestControlSvc.h@ 45386

/** @file
 * Guest control service - Common header for host service and guest clients.
 */

/*
 * Copyright (C) 2011-2013 Oracle Corporation
 *
 * This file is part of VirtualBox Open Source Edition (OSE), as
 * available from http://www.virtualbox.org. This file is free software;
 * you can redistribute it and/or modify it under the terms of the GNU
 * General Public License (GPL) as published by the Free Software
 * Foundation, in version 2 as it comes in the "COPYING" file of the
 * VirtualBox OSE distribution. VirtualBox OSE is distributed in the
 * hope that it will be useful, but WITHOUT ANY WARRANTY of any kind.
 *
 * The contents of this file may alternatively be used under the terms
 * of the Common Development and Distribution License Version 1.0
 * (CDDL) only, as it comes in the "COPYING.CDDL" file of the
 * VirtualBox OSE distribution, in which case the provisions of the
 * CDDL are applicable instead of those of the GPL.
 *
 * You may elect to license modified versions of this file under the
 * terms and conditions of either the GPL or the CDDL or both.
 */

#ifndef ___VBox_HostService_GuestControlService_h
#define ___VBox_HostService_GuestControlService_h

#include <VBox/types.h>
#include <VBox/VMMDev.h>
#include <VBox/VBoxGuest2.h>
#include <VBox/hgcmsvc.h>
#include <VBox/log.h>
#include <iprt/assert.h>
#include <iprt/string.h>

/* Everything defined in this file lives in this namespace. */
namespace guestControl {

/******************************************************************************
* Typedefs, constants and inlines                                             *
******************************************************************************/

#define HGCMSERVICE_NAME "VBoxGuestControlSvc"

/** Maximum number of concurrent guest sessions a VM can have. */
#define VBOX_GUESTCTRL_MAX_SESSIONS     32
/** Maximum number of concurrent guest objects (processes, files, ...)
 *  a guest session can have. */
#define VBOX_GUESTCTRL_MAX_OBJECTS      _2K
/** Maximum of callback contexts a guest process can have. */
#define VBOX_GUESTCTRL_MAX_CONTEXTS     _64K

/** Builds a context ID out of the session ID, object ID and an
 *  increasing count. */
#define VBOX_GUESTCTRL_CONTEXTID_MAKE(uSession, uObject, uCount) \
    (  (uint32_t)((uSession) &   0x1f) << 27 \
     | (uint32_t)((uObject)  &  0x7ff) << 16 \
     | (uint32_t)((uCount)   & 0xffff)       \
    )
#define VBOX_GUESTCTRL_CONTEXTID_MAKE_SESSION(uSession) \
    ((uint32_t)((uSession) & 0x1f) << 27)
/** Gets the session ID out of a context ID. */
#define VBOX_GUESTCTRL_CONTEXTID_GET_SESSION(uContextID) \
    ((uContextID) >> 27)
/** Gets the process ID out of a context ID. */
#define VBOX_GUESTCTRL_CONTEXTID_GET_OBJECT(uContextID) \
    (((uContextID) >> 16) & 0x7ff)
/** Gets the context count of a process out of a context ID. */
#define VBOX_GUESTCTRL_CONTEXTID_GET_COUNT(uContextID) \
    ((uContextID) & 0xffff)

/**
 * Process status when executed in the guest.
 */
enum eProcessStatus
{
    /** Process is in an undefined state. */
    PROC_STS_UNDEFINED = 0,
    /** Process has been started. */
    PROC_STS_STARTED = 1,
    /** Process terminated normally. */
    PROC_STS_TEN = 2,
    /** Process terminated via signal. */
    PROC_STS_TES = 3,
    /** Process terminated abnormally. */
    PROC_STS_TEA = 4,
    /** Process timed out and was killed. */
    PROC_STS_TOK = 5,
    /** Process timed out and was not killed successfully. */
    PROC_STS_TOA = 6,
    /** Service/OS is stopping, process was killed. */
    PROC_STS_DWN = 7,
    /** Something went wrong (error code in flags). */
    PROC_STS_ERROR = 8
};

/**
 * Input flags, set by the host. This is needed for
 * handling flags on the guest side.
 * Note: Has to match Main's ProcessInputFlag_* flags!
 */
#define INPUT_FLAG_NONE                     0x0
#define INPUT_FLAG_EOF                      RT_BIT(0)

/**
 * Guest session creation flags.
 * Only handled internally at the moment.
 */
#define SESSIONCREATIONFLAG_NONE            0x0

/**
 * Guest process creation flags.
 * Note: Has to match Main's ProcessCreateFlag_* flags!
 */
#define EXECUTEPROCESSFLAG_NONE             0x0
#define EXECUTEPROCESSFLAG_WAIT_START       RT_BIT(0)
#define EXECUTEPROCESSFLAG_IGNORE_ORPHANED  RT_BIT(1)
#define EXECUTEPROCESSFLAG_HIDDEN           RT_BIT(2)
#define EXECUTEPROCESSFLAG_NO_PROFILE       RT_BIT(3)
#define EXECUTEPROCESSFLAG_WAIT_STDOUT      RT_BIT(4)
#define EXECUTEPROCESSFLAG_WAIT_STDERR      RT_BIT(5)
#define EXECUTEPROCESSFLAG_EXPAND_ARGUMENTS RT_BIT(6)

/**
 * Pipe handle IDs used internally for referencing to
 * a certain pipe buffer.
 */
#define OUTPUT_HANDLE_ID_STDOUT_DEPRECATED  0 /* Needed for VBox hosts < 4.1.0. */
#define OUTPUT_HANDLE_ID_STDOUT             1
#define OUTPUT_HANDLE_ID_STDERR             2

/**
 * Defines for guest process array lengths.
 */
#define GUESTPROCESS_MAX_CMD_LEN            _1K
#define GUESTPROCESS_MAX_ARGS_LEN           _1K
#define GUESTPROCESS_MAX_ENV_LEN            _64K
#define GUESTPROCESS_MAX_USER_LEN           128
#define GUESTPROCESS_MAX_PASSWORD_LEN       128
#define GUESTPROCESS_MAX_DOMAIN_LEN         256

/** @name Internal tools built into VBoxService which are used in order to
 *        accomplish tasks host<->guest.
 * @{
 */
#define VBOXSERVICE_TOOL_CAT        "vbox_cat"
#define VBOXSERVICE_TOOL_LS         "vbox_ls"
#define VBOXSERVICE_TOOL_RM         "vbox_rm"
#define VBOXSERVICE_TOOL_MKDIR      "vbox_mkdir"
#define VBOXSERVICE_TOOL_MKTEMP     "vbox_mktemp"
#define VBOXSERVICE_TOOL_STAT       "vbox_stat"
/** @} */

/**
 * Input status, reported by the client.
 */
enum eInputStatus
{
    /** Input is in an undefined state. */
    INPUT_STS_UNDEFINED = 0,
    /** Input was written (partially, see cbProcessed). */
    INPUT_STS_WRITTEN = 1,
    /** Input failed with an error (see flags for rc). */
    INPUT_STS_ERROR = 20,
    /** Process has abandoned / terminated input handling. */
    INPUT_STS_TERMINATED = 21,
    /** Too much input data. */
    INPUT_STS_OVERFLOW = 30
};

/**
 * Structure keeping the context of a host callback.
 */
typedef struct VBoxGuestCtrlHostCbCtx
{
    /** HGCM Function number. */
    uint32_t uFunction;
    /** The context ID. */
    uint32_t uContextID;
    /** Protocol version of this guest session. Might
     *  be 0 if not supported. */
    uint32_t uProtocol;

} VBOXGUESTCTRLHOSTCBCTX, *PVBOXGUESTCTRLHOSTCBCTX;

/**
 * Structure for low level HGCM host callback from
 * the guest. No deep copy. */
typedef struct VBoxGuestCtrlHostCallback
{
    VBoxGuestCtrlHostCallback(uint32_t cParms, VBOXHGCMSVCPARM paParms[])
                                : mParms(cParms), mpaParms(paParms) { }

    uint32_t mParms;
    PVBOXHGCMSVCPARM mpaParms;

} VBOXGUESTCTRLHOSTCALLBACK, *PVBOXGUESTCTRLHOSTCALLBACK;

/**
 * The service functions which are callable by host.
 */
enum eHostFn
{
    /**
     * The host asks the client to cancel all pending waits and exit.
     */
    HOST_CANCEL_PENDING_WAITS = 0,
    /**
     * The host wants to create a guest session.
     */
    HOST_SESSION_CREATE = 20,
    /**
     * The host wants to close a guest session.
     */
    HOST_SESSION_CLOSE = 21,
    /**
     * The host wants to execute something in the guest. This can be a command line
     * or starting a program.
     ** Note: Legacy (VBox < 4.3) command.
     */
    HOST_EXEC_CMD = 100,
    /**
     * Sends input data for stdin to a running process executed by HOST_EXEC_CMD.
     ** Note: Legacy (VBox < 4.3) command.
     */
    HOST_EXEC_SET_INPUT = 101,
    /**
     * Gets the current status of a running process, e.g.
     * new data on stdout/stderr, process terminated etc.
     ** Note: Legacy (VBox < 4.3) command.
     */
    HOST_EXEC_GET_OUTPUT = 102,
    /**
     * Terminates a running guest process.
     */
    HOST_EXEC_TERMINATE = 110,
    /**
     * Waits for a certain event to happen. This can be an input, output
     * or status event.
     */
    HOST_EXEC_WAIT_FOR = 120,
    /**
     * Opens a guest file.
     */
    HOST_FILE_OPEN = 240,
    /**
     * Closes a guest file.
     */
    HOST_FILE_CLOSE = 241,
    /**
     * Reads from an opened guest file.
     */
    HOST_FILE_READ = 250,
    /**
     * Reads from an opened guest file at
     * a specified offset.
     */
    HOST_FILE_READ_AT = 251,
    /**
     * Write to an opened guest file.
     */
    HOST_FILE_WRITE = 260,
    /**
     * Write to an opened guest file at
     * a specified offset.
     */
    HOST_FILE_WRITE_AT = 261,
    /**
     * Changes the read & write position of an opened guest file.
     */
    HOST_FILE_SEEK = 270,
    /**
     * Gets the current file position of an opened guest file.
     */
    HOST_FILE_TELL = 271
};

/**
 * The service functions which are called by guest. The numbers may not change,
 * so we hardcode them.
 *
 * Note: Callbacks start at 100. See CALLBACKTYPE enum.
 */
enum eGuestFn
{
    /**
     * Guest waits for a new message the host wants to process on the guest side.
     * This is a blocking call and can be deferred.
     */
    GUEST_MSG_WAIT = 1,
    /**
     * Guest asks the host to cancel all pending waits the guest itself waits on.
     * This becomes necessary when the guest wants to quit but still waits for
     * commands from the host.
     */
    GUEST_CANCEL_PENDING_WAITS = 2,
    /**
     * Guest disconnected (terminated normally or due to a crash HGCM
     * detected when calling service::clientDisconnect().
     */
    GUEST_DISCONNECTED = 3,
    /**
     * Sets a message filter to only get messages which have a certain
     * context ID scheme (that is, a specific session, object etc).
     * Since VBox 4.3+.
     */
    GUEST_MSG_FILTER = 4,
    /**
     * Guest reports back a guest session status.
     */
    GUEST_SESSION_NOTIFY = 20,
    /**
     * Guests sends output from an executed process.
     */
    GUEST_EXEC_OUTPUT = 100,
    /**
     * Guest sends a status update of an executed process to the host.
     */
    GUEST_EXEC_STATUS = 101,
    /**
     * Guests sends an input status notification to the host.
     */
    GUEST_EXEC_INPUT_STATUS = 102,
    /**
     * Guest notifies the host about some I/O event. This can be
     * a stdout, stderr or a stdin event. The actual event only tells
     * how many data is available / can be sent without actually
     * transmitting the data.
     */
    GUEST_EXEC_IO_NOTIFY = 210,
    /**
     * Guest notifies the host about some file event.
     */
    GUEST_FILE_NOTIFY = 240
};

/**
 * Guest session notification types.
 * @sa HGCMMsgSessionNotify.
 */
enum GUEST_SESSION_NOTIFYTYPE
{
    GUEST_SESSION_NOTIFYTYPE_UNDEFINED = 0,
    /** Something went wrong (see rc). */
    GUEST_SESSION_NOTIFYTYPE_ERROR = 1,
    /** Guest session has been started. */
    GUEST_SESSION_NOTIFYTYPE_STARTED = 11,
    /** Guest session terminated normally. */
    GUEST_SESSION_NOTIFYTYPE_TEN = 20,
    /** Guest session terminated via signal. */
    GUEST_SESSION_NOTIFYTYPE_TES = 30,
    /** Guest session terminated abnormally. */
    GUEST_SESSION_NOTIFYTYPE_TEA = 40,
    /** Guest session timed out and was killed. */
    GUEST_SESSION_NOTIFYTYPE_TOK = 50,
    /** Guest session timed out and was not killed successfully. */
    GUEST_SESSION_NOTIFYTYPE_TOA = 60,
    /** Service/OS is stopping, process was killed. */
    GUEST_SESSION_NOTIFYTYPE_DWN = 150
};

/**
 * Guest file notification types.
 * @sa HGCMMsgFileNotify.
 */
enum GUEST_FILE_NOTIFYTYPE
{
    GUEST_FILE_NOTIFYTYPE_UNKNOWN = 0,
    GUEST_FILE_NOTIFYTYPE_ERROR = 1,
    GUEST_FILE_NOTIFYTYPE_OPEN = 10,
    GUEST_FILE_NOTIFYTYPE_CLOSE = 20,
    GUEST_FILE_NOTIFYTYPE_READ = 30,
    GUEST_FILE_NOTIFYTYPE_WRITE = 40,
    GUEST_FILE_NOTIFYTYPE_SEEK = 50,
    GUEST_FILE_NOTIFYTYPE_TELL = 60
};

/**
 * Guest file seeking types. Has to
 * match FileSeekType in Main.
 */
enum GUEST_FILE_SEEKTYPE
{
    GUEST_FILE_SEEKTYPE_BEGIN = 1,
    GUEST_FILE_SEEKTYPE_CURRENT = 4,
    GUEST_FILE_SEEKTYPE_END = 8
};

/*
 * HGCM parameter structures.
 */
#pragma pack (1)

/**
 * Waits for a host command to arrive. The structure then contains the
 * actual message type + required number of parameters needed to successfully
 * retrieve that host command (in a next round).
 */
typedef struct HGCMMsgCmdWaitFor
{
    VBoxGuestHGCMCallInfo hdr;

    /**
     * The returned command the host wants to
     * run on the guest.
     */
    HGCMFunctionParameter msg;       /* OUT uint32_t */
    /** Number of parameters the message needs. */
    HGCMFunctionParameter num_parms; /* OUT uint32_t */

} HGCMMsgCmdWaitFor;

/**
 * Asks the guest control host service to set a command
 * filter for this client. The filter itself will affect
 * the context ID bound to a command.
 */
typedef struct HGCMMsgCmdSetFilter
{
    VBoxGuestHGCMCallInfo hdr;

    /* Mask of context IDs to be filtered. */
    HGCMFunctionParameter add;      /* IN uint32_t */
    /* Exclude masked; unused. */
    HGCMFunctionParameter remove;   /* IN uint32_t */

} HGCMMsgCmdSetFilter;

/**
 * Asks the guest control host service to cancel all pending (outstanding)
 * waits which were not processed yet.  This is handy for a graceful shutdown.
 */
typedef struct HGCMMsgCancelPendingWaits
{
    VBoxGuestHGCMCallInfo hdr;
} HGCMMsgCancelPendingWaits;

/**
 * Creates a guest session.
 */
typedef struct HGCMMsgSessionOpen
{
    VBoxGuestHGCMCallInfo hdr;
    /** Context ID. */
    HGCMFunctionParameter context;
    /** The guest control protocol version this
     *  session is about to use. */
    HGCMFunctionParameter protocol;
    /** The user name to run the guest session under. */
    HGCMFunctionParameter username;
    /** The user's password. */
    HGCMFunctionParameter password;
    /** The domain to run the guest session under. */
    HGCMFunctionParameter domain;
    /** Session creation flags. */
    HGCMFunctionParameter flags;
} HGCMMsgSessionOpen;

/**
 * Terminates (closes) a guest session.
 */
typedef struct HGCMMsgSessionClose
{
    VBoxGuestHGCMCallInfo hdr;
    /** Context ID. */
    HGCMFunctionParameter context;
    /** Session termination flags. */
    HGCMFunctionParameter flags;
} HGCMMsgSessionClose;

/**
 * Reports back a guest session's status.
 */
typedef struct HGCMMsgSessionNotify
{
    VBoxGuestHGCMCallInfo hdr;
    /** Context ID. */
    HGCMFunctionParameter context;
    /** Notification type. */
    HGCMFunctionParameter type;
    /** Notification result. */
    HGCMFunctionParameter result;
} HGCMMsgSessionNotify;

/**
 * Executes a command inside the guest.
 */
typedef struct HGCMMsgProcExec
{
    VBoxGuestHGCMCallInfo hdr;
    /** Context ID. */
    HGCMFunctionParameter context;
    /** The command to execute on the guest. */
    HGCMFunctionParameter cmd;
    /** Execution flags (see IGuest::ProcessCreateFlag_*). */
    HGCMFunctionParameter flags;
    /** Number of arguments. */
    HGCMFunctionParameter num_args;
    /** The actual arguments. */
    HGCMFunctionParameter args;
    /** Number of environment value pairs. */
    HGCMFunctionParameter num_env;
    /** Size (in bytes) of environment block, including terminating zeros. */
    HGCMFunctionParameter cb_env;
    /** The actual environment block. */
    HGCMFunctionParameter env;
    union
    {
        struct
        {
            /** The user name to run the executed command under.
             *  Only for VBox < 4.3 hosts. */
            HGCMFunctionParameter username;
            /** The user's password.
             *  Only for VBox < 4.3 hosts. */
            HGCMFunctionParameter password;
            /** Timeout (in msec) which either specifies the
             *  overall lifetime of the process or how long it
             *  can take to bring the process up and running -
             *  (depends on the IGuest::ProcessCreateFlag_*). */
            HGCMFunctionParameter timeout;
        } v1;
        struct
        {
            /** Timeout (in msec) which either specifies the
             *  overall lifetime of the process or how long it
             *  can take to bring the process up and running -
             *  (depends on the IGuest::ProcessCreateFlag_*). */
            HGCMFunctionParameter timeout;
            /** Process priority. */
            HGCMFunctionParameter priority;
            /** Number of process affinity blocks. */
            HGCMFunctionParameter num_affinity;
            /** Pointer to process affinity blocks (uint64_t). */
            HGCMFunctionParameter affinity;
        } v2;
    } u;

} HGCMMsgProcExec;

/**
 * Sends input to a guest process via stdin.
 */
typedef struct HGCMMsgProcInput
{
    VBoxGuestHGCMCallInfo hdr;
    /** Context ID. */
    HGCMFunctionParameter context;
    /** The process ID (PID) to send the input to. */
    HGCMFunctionParameter pid;
    /** Input flags (see IGuest::ProcessInputFlag_*). */
    HGCMFunctionParameter flags;
    /** Data buffer. */
    HGCMFunctionParameter data;
    /** Actual size of data (in bytes). */
    HGCMFunctionParameter size;

} HGCMMsgProcInput;

/**
 * Retrieves ouptut from a previously executed process
 * from stdout/stderr.
 */
typedef struct HGCMMsgProcOutput
{
    VBoxGuestHGCMCallInfo hdr;
    /** Context ID. */
    HGCMFunctionParameter context;
    /** The process ID (PID). */
    HGCMFunctionParameter pid;
    /** The pipe handle ID (stdout/stderr). */
    HGCMFunctionParameter handle;
    /** Optional flags. */
    HGCMFunctionParameter flags;
    /** Data buffer. */
    HGCMFunctionParameter data;

} HGCMMsgProcOutput;

/**
 * Reports the current status of a guest process.
 */
typedef struct HGCMMsgProcStatus
{
    VBoxGuestHGCMCallInfo hdr;
    /** Context ID. */
    HGCMFunctionParameter context;
    /** The process ID (PID). */
    HGCMFunctionParameter pid;
    /** The process status. */
    HGCMFunctionParameter status;
    /** Optional flags (based on status). */
    HGCMFunctionParameter flags;
    /** Optional data buffer (not used atm). */
    HGCMFunctionParameter data;

} HGCMMsgProcStatus;

/**
 * Reports back the status of data written to a process.
 */
typedef struct HGCMMsgProcStatusInput
{
    VBoxGuestHGCMCallInfo hdr;
    /** Context ID. */
    HGCMFunctionParameter context;
    /** The process ID (PID). */
    HGCMFunctionParameter pid;
    /** Status of the operation. */
    HGCMFunctionParameter status;
    /** Optional flags. */
    HGCMFunctionParameter flags;
    /** Data written. */
    HGCMFunctionParameter written;

} HGCMMsgProcStatusInput;

/*
 * Guest control 2.0 messages.
 */

/**
 * Terminates a guest process.
 */
typedef struct HGCMMsgProcTerminate
{
    VBoxGuestHGCMCallInfo hdr;
    /** Context ID. */
    HGCMFunctionParameter context;
    /** The process ID (PID). */
    HGCMFunctionParameter pid;

} HGCMMsgProcTerminate;

/**
 * Waits for certain events to happen.
 */
typedef struct HGCMMsgProcWaitFor
{
    VBoxGuestHGCMCallInfo hdr;
    /** Context ID. */
    HGCMFunctionParameter context;
    /** The process ID (PID). */
    HGCMFunctionParameter pid;
    /** Wait (event) flags. */
    HGCMFunctionParameter flags;
    /** Timeout (in ms). */
    HGCMFunctionParameter timeout;

} HGCMMsgProcWaitFor;

/**
 * Opens a guest file.
 */
typedef struct HGCMMsgFileOpen
{
    VBoxGuestHGCMCallInfo hdr;
    /** UInt32: Context ID. */
    HGCMFunctionParameter context;
    /** String: File to open. */
    HGCMFunctionParameter filename;
    /** String: Open mode. */
    HGCMFunctionParameter openmode;
    /** String: Disposition. */
    HGCMFunctionParameter disposition;
    /** UInt32: Creation mode. */
    HGCMFunctionParameter creationmode;
    /** UInt64: Initial offset. */
    HGCMFunctionParameter offset;

} HGCMMsgFileOpen;

/**
 * Closes a guest file.
 */
typedef struct HGCMMsgFileClose
{
    VBoxGuestHGCMCallInfo hdr;
    /** Context ID. */
    HGCMFunctionParameter context;
    /** File handle to close. */
    HGCMFunctionParameter handle;

} HGCMMsgFileClose;

/**
 * Reads from a guest file.
 */
typedef struct HGCMMsgFileRead
{
    VBoxGuestHGCMCallInfo hdr;
    /** Context ID. */
    HGCMFunctionParameter context;
    /** File handle to read from. */
    HGCMFunctionParameter handle;
    /** Size (in bytes) to read. */
    HGCMFunctionParameter size;

} HGCMMsgFileRead;

/**
 * Reads at a specified offset from a guest file.
 */
typedef struct HGCMMsgFileReadAt
{
    VBoxGuestHGCMCallInfo hdr;
    /** Context ID. */
    HGCMFunctionParameter context;
    /** File handle to read from. */
    HGCMFunctionParameter handle;
    /** Offset where to start reading from. */
    HGCMFunctionParameter offset;
    /** Actual size of data (in bytes). */
    HGCMFunctionParameter size;

} HGCMMsgFileReadAt;

/**
 * Writes to a guest file.
 */
typedef struct HGCMMsgFileWrite
{
    VBoxGuestHGCMCallInfo hdr;
    /** Context ID. */
    HGCMFunctionParameter context;
    /** File handle to write to. */
    HGCMFunctionParameter handle;
    /** Actual size of data (in bytes). */
    HGCMFunctionParameter size;
    /** Data buffer to write to the file. */
    HGCMFunctionParameter data;

} HGCMMsgFileWrite;

/**
 * Writes at a specified offset to a guest file.
 */
typedef struct HGCMMsgFileWriteAt
{
    VBoxGuestHGCMCallInfo hdr;
    /** Context ID. */
    HGCMFunctionParameter context;
    /** File handle to write to. */
    HGCMFunctionParameter handle;
    /** Offset where to start reading from. */
    HGCMFunctionParameter offset;
    /** Actual size of data (in bytes). */
    HGCMFunctionParameter size;
    /** Data buffer to write to the file. */
    HGCMFunctionParameter data;

} HGCMMsgFileWriteAt;

/**
 * Seeks the read/write position of a guest file.
 */
typedef struct HGCMMsgFileSeek
{
    VBoxGuestHGCMCallInfo hdr;
    /** Context ID. */
    HGCMFunctionParameter context;
    /** File handle to seek. */
    HGCMFunctionParameter handle;
    /** The seeking method. */
    HGCMFunctionParameter method;
    /** The seeking offset. */
    HGCMFunctionParameter offset;

} HGCMMsgFileSeek;

/**
 * Tells the current read/write position of a guest file.
 */
typedef struct HGCMMsgFileTell
{
    VBoxGuestHGCMCallInfo hdr;
    /** Context ID. */
    HGCMFunctionParameter context;
    /** File handle to get the current position for. */
    HGCMFunctionParameter handle;

} HGCMMsgFileTell;

/******************************************************************************
* HGCM replies from the guest. These are handled in Main's low-level HGCM     *
* callbacks and dispatched to the appropriate guest object.                   *
******************************************************************************/

typedef struct HGCMReplyFileNotify
{
    VBoxGuestHGCMCallInfo hdr;
    /** Context ID. */
    HGCMFunctionParameter context;
    /** Notification type. */
    HGCMFunctionParameter type;
    /** IPRT result of overall operation. */
    HGCMFunctionParameter rc;
    union
    {
        struct
        {
            /** Guest file handle. */
            HGCMFunctionParameter handle;
        } open;
        /** Note: Close does not have any additional data (yet). */
        struct
        {
            /** Actual data read (if any). */
            HGCMFunctionParameter data;
        } read;
        struct
        {
            /** How much data (in bytes) have been successfully written. */
            HGCMFunctionParameter written;
        } write;
        struct
        {
            HGCMFunctionParameter offset;
        } seek;
        struct
        {
            HGCMFunctionParameter offset;
        } tell;
    } u;

} HGCMReplyFileNotify;

#pragma pack ()

/******************************************************************************
* Callback data structures.                                                   *
******************************************************************************/

/**
 * The guest control callback data header. Must come first
 * on each callback structure defined below this struct.
 */
typedef struct CALLBACKDATA_HEADER
{
    /** Context ID to identify callback data. This is
     *  and *must* be the very first parameter in this
     *  structure to still be backwards compatible. */
    uint32_t uContextID;
} CALLBACKDATA_HEADER, *PCALLBACKDATA_HEADER;

/*
 * These structures make up the actual low level HGCM callback data sent from
 * the guest back to the host.
 */

typedef struct CALLBACKDATA_CLIENT_DISCONNECTED
{
    /** Callback data header. */
    CALLBACKDATA_HEADER hdr;
} CALLBACKDATA_CLIENT_DISCONNECTED, *PCALLBACKDATA_CLIENT_DISCONNECTED;

typedef struct CALLBACKDATA_SESSION_NOTIFY
{
    /** Callback data header. */
    CALLBACKDATA_HEADER hdr;
    /** Notification type. */
    uint32_t uType;
    /** Notification result. Note: int vs. uint32! */
    uint32_t uResult;
} CALLBACKDATA_SESSION_NOTIFY, *PCALLBACKDATA_SESSION_NOTIFY;

typedef struct CALLBACKDATA_PROC_STATUS
{
    /** Callback data header. */
    CALLBACKDATA_HEADER hdr;
    /** The process ID (PID). */
    uint32_t uPID;
    /** The process status. */
    uint32_t uStatus;
    /** Optional flags, varies, based on u32Status. */
    uint32_t uFlags;
    /** Optional data buffer (not used atm). */
    void *pvData;
    /** Size of optional data buffer (not used atm). */
    uint32_t cbData;
} CALLBACKDATA_PROC_STATUS, *PCALLBACKDATA_PROC_STATUS;

typedef struct CALLBACKDATA_PROC_OUTPUT
{
    /** Callback data header. */
    CALLBACKDATA_HEADER hdr;
    /** The process ID (PID). */
    uint32_t uPID;
    /** The handle ID (stdout/stderr). */
    uint32_t uHandle;
    /** Optional flags (not used atm). */
    uint32_t uFlags;
    /** Optional data buffer. */
    void *pvData;
    /** Size (in bytes) of optional data buffer. */
    uint32_t cbData;
} CALLBACKDATA_PROC_OUTPUT, *PCALLBACKDATA_PROC_OUTPUT;

typedef struct CALLBACKDATA_PROC_INPUT
{
    /** Callback data header. */
    CALLBACKDATA_HEADER hdr;
    /** The process ID (PID). */
    uint32_t uPID;
    /** Current input status. */
    uint32_t uStatus;
    /** Optional flags. */
    uint32_t uFlags;
    /** Size (in bytes) of processed input data. */
    uint32_t uProcessed;
} CALLBACKDATA_PROC_INPUT, *PCALLBACKDATA_PROC_INPUT;

/**
 * General guest file notification callback.
 */
typedef struct CALLBACKDATA_FILE_NOTIFY
{
    /** Callback data header. */
    CALLBACKDATA_HEADER hdr;
    /** Notification type. */
    uint32_t uType;
    /** IPRT result of overall operation. */
    uint32_t rc;
    union
    {
        struct
        {
            /** Guest file handle. */
            uint32_t uHandle;
        } open;
        /** Note: Close does not have any additional data (yet). */
        struct
        {
            /** How much data (in bytes) have been read. */
            uint32_t cbData;
            /** Actual data read (if any). */
            void *pvData;
        } read;
        struct
        {
            /** How much data (in bytes) have been successfully written. */
            uint32_t cbWritten;
        } write;
        struct
        {
            /** New file offset after successful seek. */
            uint64_t uOffActual;
        } seek;
        struct
        {
            /** New file offset after successful tell. */
            uint64_t uOffActual;
        } tell;
    } u;
} CALLBACKDATA_FILE_NOTIFY, *PCALLBACKDATA_FILE_NOTIFY;

} /* namespace guestControl */

#endif  /* !___VBox_HostService_GuestControlService_h */