// @(#)root/meta:$Name:  $:$Id: TDataMember.cxx,v 1.2 2000/09/06 14:18:58 rdm Exp $
// Author: Fons Rademakers   04/02/95

/*************************************************************************
 * Copyright (C) 1995-2000, Rene Brun and Fons Rademakers.               *
 * All rights reserved.                                                  *
 *                                                                       *
 * For the licensing terms see $ROOTSYS/LICENSE.                         *
 * For the list of contributors see $ROOTSYS/README/CREDITS.             *
 *************************************************************************/

//////////////////////////////////////////////////////////////////////////
//
//  TDataMember.
//
// All ROOT classes may have RTTI (run time type identification) support
// added. The data is stored in so called DICTIONARY (look at TDictionary).
// Information about a class is stored in TClass.
// This information may be obtained via the CINT api - see class TCint.
// TClass has a list of TDataMember objects providing information about all
// data members of described class.
//
/*

*/
//
// TDataMember provides information about name of data member, its type,
// and comment field string. It also tries to find the TMethodCall objects
// responsible for getting/setting a value of it, and gives you pointers
// to these methods. This gives you a unique possibility to access
// protected and private (!) data members if only methods for doing that
// are defined.
// These methods could either be specified in a comment field, or found
// out automatically by ROOT: here's an example:
// suppose you have a class definition:
// 

/**************************************************************************

        class MyClass{
            private:
                Float_t fX1;
                    ...
            public:
                void    SetX1(Float_t x) {fX1 = x;};
                Float_t GetX1()          {return fX1;};
                    ...
        }

***************************************************************************/ // // // Look at the data member name and method names: a data member name has // a prefix letter (f) and has a base name X1 . The methods for getting and // setting this value have names which consist of string Get/Set and the // same base name. This convention of naming data fields and methods which // access them allows TDataMember find this methods by itself completely // automatically. To make this description complete, one should know, // that names that are automatically recognized may be also: // for data fields: either fXXX or fIsXXX; and for getter function // GetXXX() or IsXXX() [where XXX is base name]. // // As an example of using it let's analyse a few lines which get and set // a fIsEditable field in TCanvas: //

/*

    TCanvas     *c  = new TCanvas("c");   // create a canvas
    TClass      *cl = c->IsA();            // get its class description object.

    TDataMember *dm = cl->GetDataMember("fIsEditable"); //This is our data member

    TMethodCall *getter = dm->GetterMethod(); //find a method that gets value!
    Long_t l;   // declare a storage for this value;

    getter->Execute(c,"",l);  // Get this Value !!!! It will appear in l !!!


    TMethodCall *setter = dm->SetterMethod();
    setter->Execute(c,"0",);   // Set Value 0 !!!

*/ // // // This trick is widely used in ROOT TContextMenu and dialogs for obtaining // current values and put them as initial values in dialog fields. // // If you don't want to follow the convention of naming used by ROOT // you still could benefit from Getter/Setter method support: the solution // is to instruct ROOT what the names of these routines are. // The way to do it is putting this information in a comment string to a data // field in your class declaration: // //

/*

    class MyClass{
        Int_t mydata;  //  *OPTIONS={GetMethod="Get";SetMethod="Set"} 
         ...
        Int_t Get(){ return mydata;};
        void  Set(Int_t i){mydata=i;};
        }
*/ // // // However, this getting/setting functions are not the only feature of // this class. The next point is providing lists of possible settings // for the concerned data member. The idea is to have a list of possible // options for this data member, with strings identifying them. This // is used in dialogs with parameters to set - for details see // TMethodArg, TRootContextMenu, TContextMenu. This list not only specifies // the allowed value, but also provides strings naming the options. // Options are managed via TList of TOptionListItem objects. This list // is also created automatically: if a data type is an enum type, // the list will have items describing every enum value, and named // according to enum name. If type is Bool_t, two options "On" and "Off" // with values 0 and 1 are created. For other types you need to instruct // ROOT about possible options. The way to do it is the same as in case of // specifying getter/setter method: a comment string to a data field in // Your header file with class definition. // The most general format of this string is: //

/*

*OPTIONS={GetMethod="getter";SetMethod="setter";Items=(it1="title1",it2="title2", ... ) } 

*/ // // // While parsing this string ROOT firstly looks for command-tokens: // GetMethod, SetMethod, Items; They must be preceded by string // *OPTIONS= , enclosed by {} and separated by semicolons ";". // All command token should have a form TOKEN=VALUE. // All tokens are optional. // The names of getter and setter method must be enclosed by double-quote // marks (") . // Specifications of Items is slightly more complicated: you need to // put token ITEMS= and then enclose all options in curly brackets "()". // You separate options by comas ",". // Each option item may have one of the following forms: // /*
         IntegerValue  = "Text Label"

         EnumValue     = "Text Label"

        "TextValue" = Text Label"

*/ // // // One can sepcify values as Integers or Enums - when data field is an // Integer, Float or Enum type; as texts - for Text_t (more precisely: // Option_t). // // As mentioned above - this information are mainly used by contextmenu, // but also in Dump() and Inspect() methods and by the THtml class. // ////////////////////////////////////////////////////////////////////////// #include "TDataMember.h" #include "TROOT.h" #include "TGlobal.h" #include "TInterpreter.h" #include "Strlen.h" #include "Api.h" #include "TMethodCall.h" #include "TClass.h" #include "TMethod.h" #include "TIterator.h" #include "TList.h" #include "TGlobal.h" ClassImp(TDataMember) //______________________________________________________________________________ TDataMember::TDataMember(G__DataMemberInfo *info, TClass *cl) : TDictionary() { // Default TDataMember ctor. TDataMembers are constructed in TClass // via a call to TCint::CreateListOfDataMembers(). It parses the comment // string, initializes optionlist and getter/setter methods. fInfo = info; fClass = cl; fDataType = 0; fOptions = 0; fValueSetter = 0; fValueGetter = 0; if (!fInfo && !fClass) return; // default ctor is called if (fInfo) { const char *t = fInfo->Title(); if (t && t[0] != '!') SetBit(kObjIsPersistent); fDataType = 0; if (IsBasic() || IsEnum()) { if (IsBasic()) { const char *name = GetFullTypeName(); if (strcmp(name, "unsigned char") != 0 && strncmp(name, "unsigned short", sizeof ("unsigned short")) != 0 && strcmp(name, "unsigned int") != 0 && strncmp(name, "unsigned long", sizeof ("unsigned long")) != 0) name = GetTypeName(); fDataType = gROOT->GetType(name); } else { fDataType = gROOT->GetType("Int_t"); } // if (!fDataType) // Error("TDataMember", "basic data type %s not found in list of basic types", // GetTypeName()); } } // If option string exist in comment - we'll parse it and create // list of options // Option-list string has a form: // *OPTION={GetMethod="GetXXX";SetMethod="SetXXX"; // Items=(0="NULL ITEM","one"="First Item",kRed="Red Item")} // // As one can see it is possible to specify value as either numerical // value , string or enum. // One can also specify implicitly names of Getter/Setter methods. char cmt[2048]; char opt[2048]; char *opt_ptr = 0; char *ptr1 = 0; char *ptr2 = 0; char *ptr3 = 0; char *tok = 0; Int_t cnt = 0; Int_t token_cnt; Int_t i; strcpy(cmt,fInfo->Title()); if ((opt_ptr=strstr(cmt,"*OPTION={"))) { // If we found it - parsing... //let's cut the part lying between {} ptr1 = strtok(opt_ptr ,"{}"); //starts tokenizing:extracts "*OPTION={" ptr1 = strtok((char*)0,"{}"); //And now we have what we need in ptr1!!! //and save it: strcpy(opt,ptr1); // Let's extract sub-tokens extracted by ';' sign. // We'll put'em in an array for convenience; // You have to do it in this manner because you cannot use nested 'strtok' char *tokens[256]; // a storage for these sub-tokens. token_cnt = 0; cnt = 0; do { //tokenizing loop ptr1=strtok((char*) (cnt++ ? 0:opt),";"); if (ptr1){ tok=new char[strlen(ptr1)+1]; strcpy(tok,ptr1); tokens[token_cnt]=tok; token_cnt++; } } while (ptr1); // OK! Now let's check whether we have Get/Set methods encode in any string for (i=0;i<token_cnt;i++) { if (strstr(tokens[i],"GetMethod")) { ptr1 = strtok(tokens[i],"""); //tokenizing-strip text "GetMethod" ptr1 = strtok(0,"""); //tokenizing - name is in ptr1! if (GetClass()->GetMethod(ptr1,"")) // check whether such method exists fValueGetter = new TMethodCall(GetClass(),ptr1,""); continue; //next item! } if (strstr(tokens[i],"SetMethod")) { ptr1 = strtok(tokens[i],"""); ptr1 = strtok((char*)0,"""); //name of Setter in ptr1 if (GetClass()->GetMethod(ptr1,"1")) fValueSetter = new TMethodCall(GetClass(),ptr1,"1"); } } //Now let's parse option strings... Int_t opt_cnt = 0; TList *optionlist = new TList(); //storage for options strings for (i=0;i<token_cnt;i++) { if (strstr(tokens[i],"Items")) { ptr1 = strtok(tokens[i],"()"); ptr1 = strtok((char*)0,"()"); char opt[2048]; //and save it! strcpy(opt,ptr1); //now parse it... //fistly we just store strings like: xxx="Label Name" //We'll store it in TOptionListItem objects, because they're derived //from TObject and thus can be stored in TList. //It's not elegant but works. do { ptr1 = strtok(opt_cnt++ ? (char*)0:opt,","); //options extraction if (ptr1) { TOptionListItem *it = new TOptionListItem(this,1,0,0,ptr1,""); optionlist->Add(it); } } while(ptr1); } } //having all options extracted and put into list, we finally can parse //them to create a list of options... fOptions = new TList(); //create the list TIter next(optionlist); //we'll iterate through all //strings containing options TOptionListItem *it = 0; TOptionListItem *it1 = 0; while ((it=(TOptionListItem*)next())) { ptr1 = it->fOptName; Bool_t islabel = (ptr1[0]=='"'); // value is label or numerical? ptr2 = strtok(ptr1,"=""); //extract LeftHandeSide ptr3 = strtok(0,"=""); //extract RightHandedSize if (islabel) { it1=new TOptionListItem(this,-9999,0,0,ptr3,ptr2); fOptions->Add(it1); } else { //We'll try to find global enum existing in ROOT... Long_t l; Int_t *value; TGlobal *enumval = gROOT->GetGlobal(ptr1,kTRUE); if (enumval){ value = (Int_t*)(enumval->GetAddress()); l = (Long_t)(*value); } else l = atol(ptr1); it1 = new TOptionListItem(this,l,0,0,ptr3,ptr1); fOptions->Add(it1); } optionlist->Remove(it); //delete this option string from list delete it; // and dispose of it. } // Garbage colletion // dispose of temporary option list... delete optionlist; //And dispose tokens string... for (i=0;i<token_cnt;i++) if(tokens[i]) delete tokens[i]; // if option string does not exist but it's an Enum - parse it!!!! } else if (!strncmp(GetFullTypeName(),"enum",4)) { TGlobal *global = 0; TDataMember::fOptions = new TList(); char etypename[65]; strncpy(etypename,this->GetTypeName(),64); //save the typename!!! must do it! const char *gtypename = 0; TList *globals = (TList*)(gROOT->GetListOfGlobals(kTRUE)); //get all globals if (!globals) return; TIter nextglobal(globals); //iterate through all global to find while ((global=(TGlobal*)nextglobal())) { // values belonging to this enum type gtypename = global->GetTypeName(); if (strcmp(gtypename,etypename)==0) { Int_t *value = (Int_t*)(global->GetAddress()); Long_t l = (Long_t)(*value); char enumItem[128]; strcpy(enumItem,global->GetName()); TOptionListItem *it = new TOptionListItem(this,l,0,0,enumItem,enumItem); fOptions->Add(it); } } // and the case od Bool_t : we add items "ON" and "Off" } else if (!strncmp(GetFullTypeName(),"Bool_t",6)){ fOptions = new TList(); TOptionListItem *it = new TOptionListItem(this,1,0,0,"ON",0); fOptions->Add(it); it = new TOptionListItem(this,0,0,0,"Off",0); fOptions->Add(it); } else fOptions = 0; } //______________________________________________________________________________ TDataMember::~TDataMember() { // TDataMember dtor deletes adopted G__DataMemberInfo object. delete fInfo; delete fValueSetter; delete fValueGetter; if (fOptions) { fOptions->Delete(); delete fOptions; } } //______________________________________________________________________________ Int_t TDataMember::GetArrayDim() const { // Return number of array dimensions. return fInfo->ArrayDim(); } //______________________________________________________________________________ const char *TDataMember::GetArrayIndex() const { // If the data member is pointer and has a valid array size in its comments // GetArrayIndex returns a string pointing to it; // otherwise it returns an empty string. const char* val = fInfo->ValidArrayIndex(); return (val && IsaPointer() ) ? val : ""; } //______________________________________________________________________________ Int_t TDataMember::GetMaxIndex(Int_t dim) const { // Return maximum index for array dimension "dim". return fInfo->MaxIndex(dim); } //______________________________________________________________________________ const char *TDataMember::GetTypeName() const { // Get type of data member, e,g.: "class TDirectory*" -> "TDirectory". // Result needs to be used or copied immediately. return gInterpreter->TypeName(fInfo->Type()->Name()); } //______________________________________________________________________________ const char *TDataMember::GetFullTypeName() const { // Get full type description of data member, e,g.: "class TDirectory*". return fInfo->Type()->Name(); } //______________________________________________________________________________ const char *TDataMember::GetName() const { // Get data member name. return fInfo->Name(); } //______________________________________________________________________________ Int_t TDataMember::GetOffset() const { // Get offset from "this". This information is only available for // public datamembers. return fInfo->Offset(); } //______________________________________________________________________________ const char *TDataMember::GetTitle() const { // Get data member description string (comment). return fInfo->Title(); } //______________________________________________________________________________ Int_t TDataMember::Compare(TObject *obj) { // Compare to other object. Returns 0<, 0 or >0 depending on // whether "this" is lexicographically less than, equal to, or // greater than obj. return strcmp(fInfo->Name(), obj->GetName()); } //______________________________________________________________________________ ULong_t TDataMember::Hash() { // Return hash value for TDataMember based on its name. TString s = fInfo->Name(); return s.Hash(); } //______________________________________________________________________________ Bool_t TDataMember::IsBasic() const { // Return true if data member is a basic type, e.g. char, int, long... return (fInfo->Type()->Property() & kIsFundamental) ? kTRUE : kFALSE; } //______________________________________________________________________________ Bool_t TDataMember::IsEnum() const { // Return true if data member is an enum. return (fInfo->Type()->Property() & kIsEnum) ? kTRUE : kFALSE; } //______________________________________________________________________________ Bool_t TDataMember::IsaPointer() const { // Return true if data member is a pointer. return (fInfo->Property() & kIsPointer) ? kTRUE : kFALSE; } //______________________________________________________________________________ Long_t TDataMember::Property() const { // Get property description word. For meaning of bits see EProperty. return fInfo->Property(); } //______________________________________________________________________________ TList *TDataMember::GetOptions() { // Returns list of options - list of TOptionListItems return fOptions; } //______________________________________________________________________________ TMethodCall *TDataMember::GetterMethod() { // Return a TMethodCall method responsible for getting the value of data member if (!fValueGetter) { // try to guess Getter function: // we strip the fist character of name of data field ('f') and then // try to find the name of Getter by applying "Get" and "Is" // as a prefix const char *dataname = GetName(); char gettername[128]; sprintf(gettername, "Get%s", dataname+1); if (strstr(gettername, "Is")) sprintf(gettername, "Set%s", dataname+3); if (GetClass()->GetMethod(gettername, "")) return fValueGetter = new TMethodCall(fClass, gettername, ""); sprintf(gettername, "Is%s", dataname+1); if (GetClass()->GetMethod(gettername, "")) return fValueGetter = new TMethodCall(fClass, gettername, ""); } return fValueGetter; } //______________________________________________________________________________ TMethodCall *TDataMember::SetterMethod() { // Return a TMethodCall method responsible for setting the value of data member if (!fValueSetter) { // try to guess Setter function: // we strip the fist character of name of data field ('f') and then // try to find the name of Setter by applying "Set" as a prefix const char *dataname = GetName(); char settername[64]; sprintf(settername, "Set%s", dataname+1); if (strstr(settername, "Is")) sprintf(settername, "Set%s", dataname+3); if (GetClass()->GetMethod(settername, "1")) fValueSetter = new TMethodCall(fClass, settername, "1"); } return fValueSetter; } //______________________________________________________________________________ TOptionListItem::TOptionListItem(TDataMember *d, Long_t val, Long_t valmask, Long_t tglmask,const char *name, const char *label) { fDataMember = d; fValue = val; fValueMaskBit = valmask; fToggleMaskBit = tglmask; if (name){ fOptName = new char[strlen(name)+1]; strcpy(fOptName,name); } else fOptName = 0; if(label){ fOptLabel = new char[strlen(label)+1]; strcpy(fOptLabel,label); } else fOptLabel = 0; } //______________________________________________________________________________ TOptionListItem::~TOptionListItem() { if (fOptName) delete fOptName; if (fOptLabel) delete fOptLabel; }


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