CWE-ou-minkata/Sources/Plasma/PubUtilLib/plSDL/plSDL.h

/*==LICENSE==*

CyanWorlds.com Engine - MMOG client, server and tools
Copyright (C) 2011  Cyan Worlds, Inc.

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 3 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.  If not, see <http://www.gnu.org/licenses/>.

You can contact Cyan Worlds, Inc. by email legal@cyan.com
 or by snail mail at:
      Cyan Worlds, Inc.
      14617 N Newport Hwy
      Mead, WA   99021

*==LICENSE==*/
#ifndef PL_SDL_inc
#define PL_SDL_inc

//
// Code for the State Description Language (SDL)
//

#include "plSDLDescriptor.h"
#include "hsUtils.h"
#include "hsStlUtils.h"

#include "pnFactory/plCreatable.h"
#include "pnKeyedObject/plKey.h"
#include "pnKeyedObject/plUoid.h"

#include "plUnifiedTime/plUnifiedTime.h"

namespace plSDL
{
    typedef std::list<plStateDescriptor*> DescriptorList;   
    enum    GeneralPurpose
    {
        kLatestVersion  = -1,       // used when requesting the latest version of a state descriptor
        kMaxListSize    = 9999      // maximum size of var lists
    };

    enum ContentsFlags // or saveFlags, 16 bits
    {
        kHasUoid        = 0x1,      
        kHasNotificationInfo = 0x2,
        kHasTimeStamp   = 0x4,
        kSameAsDefault  = 0x8,
        kHasDirtyFlag   = 0x10,
        kWantTimeStamp  = 0x20,

        kAddedVarLengthIO = 0x8000,     // using to establish a new version in the header, can delete in 8/03
        
        kHasMaximumValue= 0xffff,   
    };

    enum RWOptions
    {
        kDirtyOnly              = 1<< 0,            // write option
        kSkipNotificationInfo   = 1<< 1,            // read/write option
        kBroadcast              = 1<< 2,            // send option
        kWriteTimeStamps        = 1<< 3,            // write out time stamps    
        kTimeStampOnRead        = 1<< 4,            // read: timestamp each var when it gets read. write: request that the reader timestamp the dirty vars.
        kTimeStampOnWrite       = 1<< 5,            // read: n/a. write: timestamp each var when it gets written.
        kKeepDirty              = 1<< 6,            // don't clear dirty flag on read
        kDontWriteDirtyFlag     = 1<< 7,            // write option. don't write var dirty flag.
        kMakeDirty              = 1<< 8,            // read/write: set dirty flag on var read/write. 
        kDirtyNonDefaults       = 1<< 9,            // dirty the var if non default value.
        kForceConvert           = 1<<10,            // always try to convert rec to latest on read
    };

    enum BehaviorFlags
    {
        kDisallowTimeStamping = 0x1,
    };

    extern const char* kAgeSDLObjectName;
    void VariableLengthRead(hsStream* s, int size, int* val);
    void VariableLengthWrite(hsStream* s, int size, int val);
};

class plStateVarNotificationInfo
{
private:
    std::string fHintString;
public:
    void SetHintString(const char* c) { fHintString=c;  }
    const char* GetHintString() const { return fHintString.c_str(); }

    void Read(hsStream* s, UInt32 readOptions);
    void Write(hsStream* s, UInt32 writeOptions) const;
};

//
// Base class for a state variable.
// A state var is a var descriptor and it's value (contents)
//
class plSimpleStateVariable;
class plSDStateVariable;
class plStateVariable
{
public:
    enum Flags
    {
        kDirty  = 0x1,  // true when someone sets the value using Set(...), can be cleared after writing
        kUsed   = 0x2   // true when it contains some value (either by Set(...) or Read() ) 
    };
protected:
    UInt32 fFlags;
    plStateVarNotificationInfo fNotificationInfo;
public:
    plStateVariable() : fFlags(0) {}
    virtual ~plStateVariable() {}

    const char* GetName() const { return GetVarDescriptor()->GetName(); }
    bool IsNamed(const char* n) const { return (n && !stricmp(GetName(), n)); }
    virtual int GetCount() const = 0;

    // conversion ops
    virtual plSimpleStateVariable* GetAsSimpleStateVar() = 0;
    virtual plSDStateVariable* GetAsSDStateVar() = 0;
    virtual plVarDescriptor* GetVarDescriptor() = 0;
    virtual const plVarDescriptor* GetVarDescriptor() const = 0;
    virtual void Alloc(int cnt=-1 /* -1 means don't change count */) = 0;
    
    virtual bool IsDirty() const { return (fFlags & kDirty) != 0; }
    virtual bool IsUsed() const  { return (fFlags & kUsed) != 0; }

    void SetDirty(bool d) { if (d) fFlags |= kDirty; else fFlags &= ~kDirty; }
    void SetUsed(bool d) { if (d) fFlags |= kUsed; else fFlags &= ~kUsed; }
    virtual void SetFromDefaults(bool timeStampNow) = 0;
    virtual void TimeStamp( const plUnifiedTime & ut=plUnifiedTime::GetCurrentTime() ) = 0;
    virtual const plUnifiedTime& GetTimeStamp() const = 0;

    plStateVarNotificationInfo& GetNotificationInfo() { return fNotificationInfo; }
    const plStateVarNotificationInfo& GetNotificationInfo() const { return fNotificationInfo; }
    
    virtual void DumpToObjectDebugger(bool dirtyOnly, int level) const {}
    virtual void DumpToStream(hsStream* stream, bool dirtyOnly, int level) const {}

    // IO
    virtual bool ReadData(hsStream* s, float timeConvert, UInt32 readOptions);
    virtual bool WriteData(hsStream* s, float timeConvert, UInt32 writeOptions) const;
};

//
// Change Notifier. 
// When a plSimpleStateVariable changes it's value by more than the given delta value,
// a notification msg will be sent to the objects that registered interest.
//
class plStateChangeNotifier
{
    friend class plSimpleStateVariable;
private:
    float fDelta;
    typedef std::vector<plKey> KeyList;
    KeyList fKeys;      // the objects to notify on change>delta
    static UInt32 fCurrentPlayerID;

    void IAddKey(plKey k);
    int IRemoveKey(plKey k);
public:
    plStateChangeNotifier();
    plStateChangeNotifier(float i, plKey k);

    void AddNotificationKey(plKey k) { IAddKey(k);  }
    void AddNotificationKeys(KeyList keys);
    int RemoveNotificationKey(plKey k);         // returns number of keys left after removal
    int RemoveNotificationKeys(KeyList keys);   // returns number of keys left after removal

    void SendNotificationMsg(const plSimpleStateVariable* srcVar, const plSimpleStateVariable* dstVar, const char* sdlName);
    
    bool GetValue(float* i) const;
    bool SetValue(float i);

    static UInt32 GetCurrentPlayerID() { return fCurrentPlayerID;   }
    static void SetCurrentPlayerID(UInt32 p) { fCurrentPlayerID=p;  }

    bool operator==(const plStateChangeNotifier &) const;
};

//
// A (non-nested) variable descriptor and its data contents.
//
class plUoid;
class plKey;
class plClientUnifiedTime;
typedef unsigned char byte;
class plSimpleStateVariable : public plStateVariable
{
protected:
    union
    {
        int*    fI;     // array of int
        short*  fS;     // array of short
        byte*   fBy;    // array of byte
        float*  fF;     // array of float
        double* fD;     // array of double
        bool*   fB;     // array of bool
        plUoid* fU;     // array of uoid
        plCreatable** fC;   // array of plCreatable ptrs
        plVarDescriptor::String32* fS32;    // array of strings
        plClientUnifiedTime* fT;    // array of Times
    };
    mutable plUnifiedTime   fTimeStamp;     // the last time the var was changed
    plSimpleVarDescriptor fVar;

    typedef std::vector<plStateChangeNotifier> StateChangeNotifiers;
    StateChangeNotifiers fChangeNotifiers;

    void IDeAlloc();
    void IInit();   // initize vars
    void IVarSet(bool timeStampNow=false);
    
    // converter fxns
    bool IConvertFromBool(plVarDescriptor::Type newType);
    bool IConvertFromInt(plVarDescriptor::Type newType);
    bool IConvertFromByte(plVarDescriptor::Type newType);
    bool IConvertFromShort(plVarDescriptor::Type newType);
    bool IConvertFromFloat(plVarDescriptor::Type newType);
    bool IConvertFromDouble(plVarDescriptor::Type newType);
    bool IConvertFromString(plVarDescriptor::Type newType);
    bool IConvertFromRGB(plVarDescriptor::Type newType);
    bool IConvertFromRGBA(plVarDescriptor::Type newType);
    bool IConvertFromRGB8(plVarDescriptor::Type newType);
    bool IConvertFromRGBA8(plVarDescriptor::Type newType);

    bool IReadData(hsStream* s, float timeConvert, int idx, UInt32 readOptions);    
    bool IWriteData(hsStream* s, float timeConvert, int idx, UInt32 writeOptions) const;

public:

    plSimpleStateVariable() { IInit(); }        
    plSimpleStateVariable(plVarDescriptor* vd) { IInit(); CopyFrom(vd); }   
    ~plSimpleStateVariable() { IDeAlloc(); }
    
    // conversion ops
    plSimpleStateVariable* GetAsSimpleStateVar() { return this; }
    plSDStateVariable* GetAsSDStateVar() { return nil; }
    bool operator==(const plSimpleStateVariable &other) const;  // assumes matching var descriptors

    void TimeStamp( const plUnifiedTime & ut=plUnifiedTime::GetCurrentTime() );
    void CopyFrom(plVarDescriptor* v);
    void CopyData(const plSimpleStateVariable* other, UInt32 writeOptions=0);
    bool SetFromString(const char* value, int idx, bool timeStampNow);      // set value from string, type.  return false on err
    char* GetAsString(int idx) const;
    bool ConvertTo(plSimpleVarDescriptor* toVar, bool force=false);         // return false on err
    void Alloc(int cnt=-1 /* -1 means don't change count */);                                   // alloc memory after setting type
    void Reset();

    // setters
    bool Set(float v, int idx=0);
    bool Set(float* v, int idx=0);                          // floatVector
    bool Set(double v, int idx=0);
    bool Set(double* v, int idx=0);                         // doubleVector
    bool Set(int v, int idx=0);
    bool Set(int* v, int idx=0) { return Set(*v, idx);  }   // helper since there is no int vec type
    bool Set(byte v, int idx=0);
    bool Set(byte* v, int idx=0);                           // byteVector
    bool Set(short v, int idx=0);
    bool Set(short* v, int idx=0) { return Set(*v, idx); }  // helper since there is no short vec type
    bool Set(bool v, int idx=0);
    bool Set(bool* v, int idx=0) { return Set(*v, idx); }   // helper since there is no bool vec type
    bool Set(const char* v, int idx=0);                     // string
    bool Set(const plKey& v, int idx=0);
    bool Set(plCreatable*, int idx=0);                      // only SDL generated by the server is allowed to use this type.
    void SetFromDefaults(bool timeStampNow);
    
    // getters
    bool Get(int* value, int idx=0) const;
    bool Get(short* value, int idx=0) const;
    bool Get(byte* value, int idx=0) const;             // returns byte or byteVector
    bool Get(float* value, int idx=0) const;            // returns float or floatVector
    bool Get(double* value, int idx=0) const;           // returns double or doubleVector
    bool Get(bool* value, int idx=0) const;
    bool Get(char value[], int idx=0) const;
    bool Get(plKey* value, int idx=0) const;
    bool Get(plCreatable** value, int idx=0) const;
    const plUnifiedTime& GetTimeStamp() const { return fTimeStamp;  }

    // Special backdoor so the KI Manager can get the key name without having a ResMgr
    const char* GetKeyName(int idx=0) const;

    int GetCount() const { return fVar.GetCount(); }    // helper
    plVarDescriptor* GetVarDescriptor() { return &fVar; }
    plSimpleVarDescriptor* GetSimpleVarDescriptor() { return fVar.GetAsSimpleVarDescriptor(); }
    const plVarDescriptor* GetVarDescriptor() const { return &fVar; }
    const plSimpleVarDescriptor* GetSimpleVarDescriptor() const { return fVar.GetAsSimpleVarDescriptor(); }

    // State Change Notification
    void AddStateChangeNotification(plStateChangeNotifier& n);
    void RemoveStateChangeNotification(plKey notificationObj);      // remove all with this key 
    void RemoveStateChangeNotification(plStateChangeNotifier n);    // remove ones which match
    void NotifyStateChange(const plSimpleStateVariable* other, const char* sdlName);        // send notification msg if necessary, internal use

    void DumpToObjectDebugger(bool dirtyOnly, int level) const;
    void DumpToStream(hsStream* stream, bool dirtyOnly, int level) const;

    // IO
    bool ReadData(hsStream* s, float timeConvert, UInt32 readOptions);  
    bool WriteData(hsStream* s, float timeConvert, UInt32 writeOptions) const;
};

//
// A list of state data records, all of which are the same kind. 
// Corresponds to a SD var descriptor.
//
class plStateDataRecord;
class plSDStateVariable : public plStateVariable
{
public:
    typedef std::vector<const plStateDataRecord*> ConstDataRecList; 
protected:
    typedef std::vector<plStateDataRecord*> DataRecList;
    DataRecList fDataRecList;   
    plSDVarDescriptor* fVarDescriptor;

    void IDeInit();
public:
    plSDStateVariable(plSDVarDescriptor* sdvd);
    ~plSDStateVariable();   // delete all records

    // conversion ops
    plSimpleStateVariable* GetAsSimpleStateVar() { return nil; }
    plSDStateVariable* GetAsSDStateVar() { return this; }
    bool operator==(const plSDStateVariable &other) const;  // assumes matching var descriptors

    void ConvertTo(plSDStateVariable* otherSDVar, bool force=false);
    void CopyFrom(plSDStateVariable* other, UInt32 writeOptions=0);
    void UpdateFrom(plSDStateVariable* other, UInt32 writeOptions=0);
    void AddStateDataRecord(plStateDataRecord *sdr) { fDataRecList.push_back(sdr); SetDirty(true); SetUsed(true); }
    void InsertStateDataRecord(plStateDataRecord *sdr, int i) { fDataRecList[i] = sdr; SetDirty(true); SetUsed(true);}
    void SetFromDefaults(bool timeStampNow);
    void TimeStamp( const plUnifiedTime & ut=plUnifiedTime::GetCurrentTime() );
    const plUnifiedTime& GetTimeStamp() const { static plUnifiedTime foo; return foo; }
    
    void Alloc(int cnt=-1 /* -1 means don't change count */);   // wipe and re-create
    void Alloc(plSDVarDescriptor* sdvd, int cnt=-1);            // wipe and re-create
    void Resize(int cnt);
    
    bool IsDirty() const;
    bool IsUsed() const;

    // getters
    plStateDataRecord* GetStateDataRecord(int i) { return fDataRecList[i]; }
    const plStateDataRecord* GetStateDataRecord(int i) const { return fDataRecList[i]; }
    int GetCount() const { return fDataRecList.size(); }
    int GetUsedCount() const;
    int GetDirtyCount() const;
    void GetUsedDataRecords(ConstDataRecList*) const;
    void GetDirtyDataRecords(ConstDataRecList*) const;
    plVarDescriptor* GetVarDescriptor() { return fVarDescriptor; }
    plSDVarDescriptor* GetSDVarDescriptor() { return fVarDescriptor->GetAsSDVarDescriptor(); }
    const plVarDescriptor* GetVarDescriptor() const { return fVarDescriptor; }
    const plSDVarDescriptor* GetSDVarDescriptor() const { return fVarDescriptor->GetAsSDVarDescriptor(); }
    void FlagNewerState(const plSDStateVariable&, bool respectAlwaysNew);
    void FlagAlwaysNewState();
    void DumpToObjectDebugger(bool dirtyOnly, int level) const;
    void DumpToStream(hsStream* stream, bool dirtyOnly, int level) const;
    
    // IO
    bool ReadData(hsStream* s, float timeConvert, UInt32 readOptions);  
    bool WriteData(hsStream* s, float timeConvert, UInt32 writeOptions) const;
};

//
// Contains the actual data contents and points to its associated descriptor
//
class plNetMsgSDLState;
class plStateDataRecord : public plCreatable
{
public:
    typedef std::vector<plSimpleStateVariable*> SimpleVarsList;
    typedef std::vector<plSDStateVariable*> SDVarsList;
    enum Flags
    {
        kVolatile = 0x1
    };
protected:
    typedef std::vector<plStateVariable*> VarsList;

    const plStateDescriptor* fDescriptor;
    plUoid      fAssocObject;       // optional
    VarsList    fVarsList;          // list of variables
    VarsList    fSDVarsList;        // list of nested data records
    UInt32      fFlags;
    static const UInt8 kIOVersion;  // I/O Version
    
    void IDeleteVarsList(VarsList& vars);
    void IInitDescriptor(const char* name, int version);    // or plSDL::kLatestVersion
    void IInitDescriptor(const plStateDescriptor* sd);
    
    void IReadHeader(hsStream* s);
    void IWriteHeader(hsStream* s) const;
    bool IConvertVar(plSimpleStateVariable* fromVar, plSimpleStateVariable* toVar, bool force);

    plStateVariable* IFindVar(const VarsList& vars, const char* name) const;
    int IGetNumUsedVars(const VarsList& vars) const;
    int IGetUsedVars(const VarsList& varsOut, VarsList *varsIn) const;  // build a list of vars that have data
    bool IHasUsedVars(const VarsList& vars) const;

    int IGetNumDirtyVars(const VarsList& vars) const;
    int IGetDirtyVars(const VarsList& varsOut, VarsList *varsIn) const; // build a list of vars that are dirty
    bool IHasDirtyVars(const VarsList& vars) const;
public:
    CLASSNAME_REGISTER( plStateDataRecord );
    GETINTERFACE_ANY( plStateDataRecord, plCreatable);

    plStateDataRecord(const char* sdName, int version=plSDL::kLatestVersion);
    plStateDataRecord(plStateDescriptor* sd);
    plStateDataRecord(const plStateDataRecord &other, UInt32 writeOptions=0 ):fFlags(0) { CopyFrom(other, writeOptions); }
    plStateDataRecord():fFlags(0) {}
    ~plStateDataRecord();
    
    bool ConvertTo(plStateDescriptor* other, bool force=false );
    bool operator==(const plStateDataRecord &other) const;  // assumes matching state descriptors

    UInt32 GetFlags() const { return fFlags;    }
    void SetFlags(UInt32 f) { fFlags =f;    }
    
    plSimpleStateVariable* FindVar(const char* name) const { return (plSimpleStateVariable*)IFindVar(fVarsList, name); }
    plSDStateVariable* FindSDVar(const char* name) const { return (plSDStateVariable*)IFindVar(fSDVarsList, name); }
    
    plStateDataRecord& operator=(const plStateDataRecord& other) { CopyFrom(other); }
    void CopyFrom(const plStateDataRecord& other, UInt32 writeOptions=0);
    void UpdateFrom(const plStateDataRecord& other, UInt32 writeOptions=0);
    void SetFromDefaults(bool timeStampNow);
    void TimeStampDirtyVars();
    
    int GetNumVars() const { return fVarsList.size();   }
    plSimpleStateVariable* GetVar(int i) const { return (plSimpleStateVariable*)fVarsList[i];   }
    int GetNumSDVars() const { return fSDVarsList.size();   }
    plSDStateVariable* GetSDVar(int i) const { return (plSDStateVariable*)fSDVarsList[i];   }

    // Used vars
    bool IsUsed() const { return (HasUsedVars() || HasUsedSDVars()); }
    
    int GetNumUsedVars() const { return IGetNumUsedVars(fVarsList); }
    int GetUsedVars(SimpleVarsList *vars) const { return IGetUsedVars(fVarsList, (VarsList*)vars); }    // build a list of vars that have data
    bool HasUsedVars() const { return IHasUsedVars(fVarsList); }

    int GetNumUsedSDVars() const { return IGetNumUsedVars(fSDVarsList); }
    int GetUsedSDVars(SDVarsList *vars) const { return IGetUsedVars(fSDVarsList, (VarsList*)vars); }    // build a list of SD vars that have data
    bool HasUsedSDVars() const { return IHasUsedVars(fSDVarsList); }

    // Dirty Vars
    bool IsDirty() const { return (HasDirtyVars() || HasDirtySDVars()); }   
    
    int GetNumDirtyVars() const { return IGetNumDirtyVars(fVarsList); }
    int GetDirtyVars(SimpleVarsList *vars) const { return IGetDirtyVars(fVarsList, (VarsList*)vars); }  // build a list of vars that are dirty
    bool HasDirtyVars() const { return IHasDirtyVars(fVarsList); }

    int GetNumDirtySDVars() const { return IGetNumDirtyVars(fSDVarsList); }
    int GetDirtySDVars(SDVarsList *vars) const { return IGetDirtyVars(fSDVarsList, (VarsList*)vars); }; // build a list of Sdvars that are dirty
    bool HasDirtySDVars() const { return IHasDirtyVars(fSDVarsList); }

    const plStateDescriptor* GetDescriptor() const { return fDescriptor; }
    void SetDescriptor(const char* sdName, int version);
    
    plNetMsgSDLState* PrepNetMsg(float timeConvert, UInt32 writeOptions) const; // create/prep a net msg with this data
    
    void SetAssocObject(const plUoid& u) { fAssocObject=u; }        // optional 
    plUoid* GetAssocObject() { return &fAssocObject; }      // optional
    const plUoid* GetAssocObject() const { return &fAssocObject; }      // optional

    // utils
    void FlagDifferentState(const plStateDataRecord& other);    // mark items which differ from 'other' as dirty
    void FlagNewerState(const plStateDataRecord& other, bool respectAlwaysNew=false);   // mark items which are newer than 'other' as dirty
    void FlagAlwaysNewState();  // mark 'alwaysNew' items as dirty
    void DumpToObjectDebugger(const char* msg, bool dirtyOnly=false, int level=0) const;
    void DumpToStream(hsStream* stream, const char* msg, bool dirtyOnly=false, int level=0) const;

    // IO
    bool Read(hsStream* s, float timeConvert, UInt32 readOptions=0);
    void Write(hsStream* s, float timeConvert, UInt32 writeOptions=0) const;

    static bool ReadStreamHeader(hsStream* s, char** name, int* version, plUoid* objUoid=nil);
    void WriteStreamHeader(hsStream* s, plUoid* objUoid=nil) const;
};

//
// Simple SDL parser
//
class plSDLMgr;
class plSDLParser
{
private:
    bool IReadDescriptors() const;
    bool ILoadSDLFile(const char* fileName) const;
    bool IParseVarDesc(const char* fileName, hsStream* stream, char token[], plStateDescriptor*& curDesc, 
        plVarDescriptor*& curVar) const;
    bool IParseStateDesc(const char* fileName, hsStream* stream, char token[], plStateDescriptor*& curDesc) const;

    void DebugMsg(char* fmt, ...) const;
    void DebugMsgV(char* fmt, va_list args) const;

public:

    bool Parse() const; // reads sdl folder, creates descriptor list
};

//
// Holds, loads and unloads all state descriptors from sdl files.
// Singleton.
//
class plNetApp;
class plSDLMgr
{
    friend class plSDLParser;
private:
    std::string fSDLDir;
    plSDL::DescriptorList fDescriptors;
    plNetApp*   fNetApp;
    UInt32      fBehaviorFlags;

    void IDeleteDescriptors(plSDL::DescriptorList* dl);
public:
    plSDLMgr();
    ~plSDLMgr();

    static plSDLMgr* GetInstance();
    plStateDescriptor* FindDescriptor(const char* name, int version, const plSDL::DescriptorList * dl=nil) const;   // version or kLatestVersion
    
    const plSDL::DescriptorList * GetDescriptors( void ) const { return &fDescriptors;}

    void SetSDLDir(const char* s) { fSDLDir=s; }
    const char* GetSDLDir() const { return fSDLDir.c_str(); }

    void SetNetApp(plNetApp* a) { fNetApp=a; }
    plNetApp* GetNetApp() const { return fNetApp; }
    
    bool Init( UInt32 behaviorFlags=0 );    // parse sdl folder
    void DeInit();
    UInt32 GetBehaviorFlags() const { return fBehaviorFlags; }
    void SetBehaviorFlags(UInt32 v) { fBehaviorFlags=v; }
    bool AllowTimeStamping() const { return ! ( fBehaviorFlags&plSDL::kDisallowTimeStamping ); }

    // I/O - return # of bytes read/written
    int Write(hsStream* s, const plSDL::DescriptorList* dl=nil);    // write descriptors to a stream
    int Read(hsStream* s, plSDL::DescriptorList* dl=nil);       // read descriptors into provided list (use legacyList if nil)
};

#endif  // PL_SDL_inc