String Lookup Table

I created this code for a mod I was working on and I thought I'd share it with the community. --deathz0rz 11:31, 13 Nov 2005 (PST)

/* Copyright (c) 2005 Jethro "deathz0rz" Beekman. All rights reserved.

Redistribution and use in source and binary forms, with or without modification, 
are permitted provided that the following conditions are met:

   1. Redistributions of source code must retain the above copyright notice, 
   this list of conditions and the following disclaimer.

   2. Redistributions in binary form must reproduce the above copyright notice, 
   this list of conditions and the following disclaimer in the documentation 
   and/or other materials provided with the distribution.

   3. All advertising materials mentioning features or use of this software must 
   display the following acknowledgement: This product includes software 
   developed by Jethro Beekman.

   4. Neither the name of the author nor the names of its contributors may be 
   used to endorse or promote products derived from this software without 
   specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED 
WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF 
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT 
SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, 
EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT 
OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING 
IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY 
OF SUCH DAMAGE.

================================================================================

The contents of this file are designed for use with the Valve Source SDK, 
however, it's function can be adepted to work with other code, such as STL. 
Supplied are convenience macro's designed to convert from constant names to 
constant values. I think an example explains their usages best:

================================================================================
==                               sourcecontrol.h                              ==
================================================================================

//(...)
#include "stringlookup.h"
//(...)

#define FSTATUS_UNCHANGED	0
#define FSTATUS_ADDED		0x01
#define FSTATUS_REMOVED		0x02
#define FSTATUS_CHANGED		(FSTATUS_ADDED|FSTATUS_REMOVED)
#define FSTATUS_DIRECTORY	0x04
#define FSTATUS_HIDDEN		0x08
#define FSTATUS_SYSTEM		0x10
#define FSTATUS_READONLY	0x20
#define FSTATUS_ARCHIVE		0x40

DECLARE_STRING_LOOKUP_CONSTANTS(unsinged int,FSTATUS_LOOKUP)

//You don't have to do this, but it saves typing
#define FSTATUS(key,var) STRING_LOOKUP(FSTATUS_LOOKUP,key,var)

//(...)

================================================================================
==                              sourcecontrol.cpp                             ==
================================================================================

//(...)
#include "sourcecontrol.h"
//(...)

DEFINE_STRING_LOOKUP_CONSTANTS(FSTATUS_LOOKUP)
	ADD_LOOKUP(FSTATUS_UNCHANGED)
	ADD_LOOKUP(FSTATUS_ADDED)
	ADD_LOOKUP(FSTATUS_REMOVED)
	ADD_LOOKUP(FSTATUS_CHANGED)
	ADD_LOOKUP(FSTATUS_DIRECTORY)
	ADD_LOOKUP(FSTATUS_HIDDEN)
	ADD_LOOKUP(FSTATUS_SYSTEM)
	ADD_LOOKUP(FSTATUS_READONLY)
	ADD_LOOKUP(FSTATUS_ARCHIVE)
END_STRING_LOOKUP_CONSTANTS()

//(...)
	KeyValues *pKV;
//(...)
	unsinged int uiStatus;
	if (!FSTATUS(pKV->GetString("status"),uiStatus))
		Warning("Invalid status constant %s!\n",pKV->GetString("status"));
//(...)

//Of course, this is quite inconvenient, because the declared constants are 
//obviously meant to be used as bit flags. For that, a different macro is 
//supplied.

//(...)
	KeyValues *pKV;
//(...)
	unsinged int uiStatus=0;
	CUtlVector<unsinged int>* auiFlags;
	auiFlags=CONVERT_STRING(FSTATUS_LOOKUP,pKV->GetString("status"));
	for (int i=0;i<auiFlags->Count();i++)
		uiStatus|=(*auiFlags)[i];
//(...)

//NOTE: A character that is not a letter, a capital letter, a number or an 
//underscore is considered a separator.

================================================================================

*/

#include <UtlStringMap.h>
#include <UtlVector.h>

#ifndef STRING_LOOKUP_H
#define STRING_LOOKUP_H

template<typename T> class CStringLookupConstantTable
{
protected:
	typedef struct m_stringconstant_s {
		const char*	pszKey;
		T			tValue;
	} m_stringconstant_t;

	CUtlStringMap<T*> m_StringMap;

public:
	inline bool FindKey(const char *pszKey, T *ptValue)
	{
		if (m_StringMap.Defined(pszKey))
		{
			if (ptValue)
				*ptValue=*m_StringMap[pszKey];
			return true;
		}
		else
		{
			return false;
		}
	};

	CUtlVector<T>* FromString(const char* pszStr)
	{  
		static CUtlVector<T> LocalArray;  
		static char szNoSep[]="qwertyuiopasdfghjklzxcvbnmQWERTYUIOPASDFGHJKLZXCVBNM1234567890_";  
		char* pszCur=NULL;  
		char* pszIt;  
		char szTmp[256];
		T tTmp;

		LocalArray.RemoveAll();  

		for(pszIt=(char*)pszStr;*pszIt;pszIt++)  
		{  
			if (pszCur)  
			{  
				if (!strchr(szNoSep,*pszIt))  
				{  
					Q_strncpy(szTmp,pszCur,min((int)(pszIt-pszCur)+1,256)); 
					if (FindKey(szTmp,&tTmp))
						LocalArray.AddToTail(tTmp);  
					pszCur=NULL;  
				}  
			}  
			else  
			{  
				if (strchr(szNoSep,*pszIt))  
				{  
					pszCur=pszIt;  
				}  
			}  
		}  
		if (pszCur)  
		{  
			Q_strncpy(szTmp,pszCur,min((int)(pszIt-pszCur)+1,256));  
			if (FindKey(szTmp,&tTmp))
				LocalArray.AddToTail(tTmp);
		}  
		return &LocalArray;  
	}
};

//SLTP means String Lookup Table Private
#define DECLARE_STRING_LOOKUP_CONSTANTS(type,identifier) \
	namespace SLTP__##identifier \
	{ \
		class CStringLookupConstantTable__##identifier : public CStringLookupConstantTable<type> \
		{ \
		public: \
			inline CUtlVector<type>* FromString(const char* pszStr) { return CStringLookupConstantTable<type>::FromString(pszStr); }; \
			CStringLookupConstantTable__##identifier(); \
			~CStringLookupConstantTable__##identifier() {}; \
		}; \
	} \
	\
	extern SLTP__##identifier::CStringLookupConstantTable__##identifier g_StringLookupConstantTable__##identifier;

#define STRING_LOOKUP(identifier,key,var) \
	g_StringLookupConstantTable__##identifier.FindKey(key,&var)

#define STRING_EXISTS(identifier,key) \
	g_StringLookupConstantTable__##identifier.FindKey(key,NULL)

#define CONVERT_STRING(identifier,str) \
	g_StringLookupConstantTable__##identifier.FromString(str);

#define DEFINE_STRING_LOOKUP_CONSTANTS(type,identifier) \
	SLTP__##identifier::CStringLookupConstantTable__##identifier g_StringLookupConstantTable__##identifier; \
	namespace SLTP__##identifier \
	{ \
		CStringLookupConstantTable__##identifier::CStringLookupConstantTable__##identifier() \
		{ \
			static m_stringconstant_t aConstants[] = {

#define ADD_LOOKUP(macro) \
				#macro, macro, \

#define END_STRING_LOOKUP_CONSTANTS() \
			}; \
			for (int i=0;i<sizeof(aConstants)/sizeof(m_stringconstant_t);i++) \
			{ \
				m_StringMap[aConstants[i].pszKey]=&aConstants[i].tValue; \
			} \
		}; \
	};

#endif //!STRING_LOOKUP_H

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