/*++ Copyright (c) 1991 Microsoft Corporation Module Name: SUB_STRING Abstract: This module contains the definition of the SUB_STRING class. Author: Steve Rowe (stever) Environment: ULIB, User Mode Notes: A substring is a subsequence of characters taken from a "base" string. Substrings are useful in those cases in which we want to operate on "chunks" of a given string (e.g. parsing), without having to create separate strings for each one. One must be careful when using substrings, though. Since substrings depend on a base string, the base string must exist during the life span of all its substrings. In other words, the base string must not be deleted before having deleted all the substrings obtained from it. Note that GENERIC_STRINGs have no substring support. It is up to the derived string classes to provide it. Since substrings are just "windows" into a base string, any modification of a substring will be reflected in the base string (hence in all other substrings). This is why we have two classes of substrings: SUB_STRING allows only read operations. Note however that one can modify the base string directly. DYNAMIC_SUB_STRING is derived from the above, and it allows write operations. Needless to say, you should not use this class unless you're sure of what you are doing. Substring objects cannot be created and initialized directly by the user, they must be obtained thru a base string class with substring support. Substrings pertaining to the same base string are chained together in a doubly-linked queue. Since substrings have no knowledge of the internals of their base string, the chain has a dummy element as its head. In order to provide substring support, the base string must follow these steps: 1.- Before spawning any substring, the substring chain head must be created and initialized using the InitializeChainHead() method. Note that this substring is a dummy one, beknown only to the base string. 2.- Whenever spawning a new substring, it must be linked to the chain using the InitializeChainNode() method. Any substring already in the chain may be use as argument, but the obvious choice is the chain head. 3.- Each time that the size of the string changes, the Update() of the chain head must be invoked. 4.- Before destroying a base string, you have to make sure that all its substrings have gone away. This means that the chain head must be the only element of the chain. Use the HasLinks() method to verify this. 5.- Don't forget to destroy the chain head before destorying the base string. --*/ // // This class is no longer supported // #include "wstring.hxx" #define _SUB_STRING_ #if !defined (_SUB_STRING_) #define _SUB_STRING_ #include "string.hxx" DECLARE_CLASS( SUB_STRING ); class SUB_STRING : public GENERIC_STRING { friend SUB_STRING; public: DECLARE_CONSTRUCTOR( SUB_STRING ); DECLARE_CAST_MEMBER_FUNCTION( SUB_STRING ); VIRTUAL ~SUB_STRING ( ); NONVIRTUAL BOOLEAN HasLinks ( ); NONVIRTUAL BOOLEAN InitializeChainHead ( IN PGENERIC_STRING BaseString ); NONVIRTUAL BOOLEAN InitializeChainNode ( IN OUT PSUB_STRING SubString, IN CHNUM Position, IN CHNUM Length ); VIRTUAL PBYTE GetInternalBuffer ( IN CHNUM Position DEFAULT 0 ) CONST; VIRTUAL BOOLEAN IsChAt ( IN WCHAR Char, IN CHNUM Position DEFAULT 0 ) CONST; VIRTUAL BOOLEAN MakeNumber ( OUT PLONG Number, IN CHNUM Position DEFAULT 0, IN CHNUM Length DEFAULT TO_END ) CONST; VIRTUAL ULONG QueryByteCount ( IN CHNUM Position DEFAULT 0, IN CHNUM Length DEFAULT TO_END ) CONST; VIRTUAL WCHAR QueryChAt( IN CHNUM Position DEFAULT 0 ) CONST; VIRTUAL CHNUM QueryChCount ( ) CONST; VIRTUAL PGENERIC_STRING QueryGenericString ( IN CHNUM Position DEFAULT 0, IN CHNUM Length DEFAULT TO_END ) CONST; VIRTUAL PSTR QuerySTR( IN CHNUM Position DEFAULT 0, IN CHNUM Length DEFAULT TO_END, IN OUT PSTR Buffer DEFAULT NULL, IN ULONG BufferSize DEFAULT 0 ) CONST; VIRTUAL PSUB_STRING QuerySubString ( IN CHNUM Position DEFAULT 0, IN CHNUM Length DEFAULT TO_END, OUT PSUB_STRING SubString DEFAULT NULL ); VIRTUAL PWSTR QueryWSTR ( IN CHNUM Position DEFAULT 0, IN CHNUM Length DEFAULT TO_END, IN OUT PWSTR Buffer DEFAULT NULL, IN ULONG BufferSize DEFAULT 0, IN BOOLEAN ForceNull DEFAULT TRUE ) CONST; VIRTUAL BOOLEAN Replace ( IN PCGENERIC_STRING String2, IN CHNUM Position DEFAULT 0, IN CHNUM Length DEFAULT TO_END, IN CHNUM Position2 DEFAULT 0, IN CHNUM Length2 DEFAULT TO_END ); VIRTUAL BOOLEAN SetChAt ( IN WCHAR Char, IN CHNUM Position DEFAULT 0, IN CHNUM Length DEFAULT TO_END ); VIRTUAL CHNUM Strchr ( IN WCHAR Char, IN CHNUM Position DEFAULT 0, IN CHNUM Length DEFAULT TO_END ) CONST; VIRTUAL LONG Strcmp ( IN PCGENERIC_STRING GenericString ) CONST; VIRTUAL CHNUM Strcspn ( IN PCGENERIC_STRING GenericString, IN CHNUM Position DEFAULT 0, IN CHNUM Length DEFAULT TO_END ) CONST; VIRTUAL LONG Stricmp ( IN PCGENERIC_STRING GenericString ) CONST; VIRTUAL LONG StringCompare ( IN CHNUM Position1, IN CHNUM Length1, IN PCGENERIC_STRING GenericString2, IN CHNUM Position2, IN CHNUM Length2, IN USHORT CompareFlags DEFAULT COMPARE_IGNORECASE ) CONST; VIRTUAL CHNUM StrLen ( ) CONST; VIRTUAL CHNUM Strrchr ( IN WCHAR Char, IN CHNUM Position DEFAULT 0, IN CHNUM Length DEFAULT TO_END ) CONST; VIRTUAL CHNUM Strspn ( IN PCGENERIC_STRING GenericString, IN CHNUM Position DEFAULT 0, IN CHNUM Length DEFAULT TO_END ) CONST; VIRTUAL CHNUM Strstr ( IN PCGENERIC_STRING GenericString, IN CHNUM Position DEFAULT 0, IN CHNUM Length DEFAULT TO_END ) CONST; NONVIRTUAL BOOLEAN Update ( IN CHNUM Length ); protected: NONVIRTUAL PGENERIC_STRING GetBaseString ( ); NONVIRTUAL PSUB_STRING GetNextInChain ( ); NONVIRTUAL PSUB_STRING GetPreviousInChain ( ); NONVIRTUAL VOID GetValidLength( IN CHNUM Position, IN OUT PCHNUM Length ) CONST; NONVIRTUAL CHNUM QueryStartingPosition ( ) CONST; NONVIRTUAL VOID SetChCount( IN CHNUM NewCount ); private: NONVIRTUAL VOID Construct ( ); NONVIRTUAL VOID Destroy ( ); PGENERIC_STRING _BaseString; // base string to take substring CHNUM _StartingPosition; // starting index within base CHNUM _CountOfChars; // # of chars in substring PSUB_STRING _Previous; // Previous in chain PSUB_STRING _Next; // Next in chain #if DBG==1 ULONG _Signature; BOOLEAN _Initialized; #endif }; INLINE PGENERIC_STRING SUB_STRING::GetBaseString ( ) /*++ Routine Description: Gets a pointer to the base string Arguments: none Return Value: Pointer to the base string --*/ { DebugAssert( _Initialized ); return _BaseString; } INLINE PSUB_STRING SUB_STRING::GetNextInChain ( ) /*++ Routine Description: Gets a pointer to next substring in the chain Arguments: none Return Value: Pointer to substring --*/ { DebugAssert( _Initialized ); return _Next; } INLINE PSUB_STRING SUB_STRING::GetPreviousInChain ( ) /*++ Routine Description: Gets a pointer to previous substring in the chain Arguments: none Return Value: Pointer to the previous substring --*/ { DebugAssert( _Initialized ); return _Previous; } INLINE VOID SUB_STRING::GetValidLength ( IN CHNUM Position, IN OUT PCHNUM Length ) CONST /*++ Routine Description: If the length passed has the magic value TO_END, then it is updated to be the from the passed position up to the end of the substring. Arguments: Position - Supplies a starting position within the substring Length - Supplies a length Return Value: none --*/ { DebugAssert(_Initialized ); DebugAssert( Position <= _CountOfChars ); if ( *Length == TO_END ) { *Length = _CountOfChars - Position; } DebugAssert( Position + *Length <= _CountOfChars ); } INLINE BOOLEAN SUB_STRING::HasLinks ( ) /*++ Routine Description: Determines if the substring has forward and backward links Arguments: none Return Value: TRUE if the stubstring has forward or backward links FALSE otherwise --*/ { DebugAssert( _Initialized ); return ( (GetNextInChain() != NULL ) || (GetPreviousInChain() != NULL ) ); } INLINE CHNUM SUB_STRING::QueryStartingPosition ( ) CONST /*++ Routine Description: Returns the starting character position within the base string. Arguments: None. Return Value: The starting character position within the base string. --*/ { DebugAssert( _Initialized ); return _StartingPosition; } INLINE VOID SUB_STRING::SetChCount ( IN CHNUM NewCount ) /*++ Routine Description: Sets the number of characters in the substring Arguments: NewCount - Supplies the new count of characters Return Value: none --*/ { DebugAssert( _Initialized ); _CountOfChars = NewCount; } #endif // _SUB_STRING_ /*++ Copyright (c) 1990 Microsoft Corporation Module Name: DYNAMIC_SUB_STRING Abstract: This module contains the definition of the DYNAMIC_SUB_STRING class. Author: steve rowe stever 2/1/91 Notes: DYNAMIC_SUB_STRINGs can modify the base string (see notes for SUB_STRING class). Revision History: --*/ #define _DYNAMIC_SUB_STRING_ #if !defined (_DYNAMIC_SUB_STRING_) #define _DYNAMIC_SUB_STRING_ DECLARE_CLASS( DYNAMIC_SUB_STRING ); class DYNAMIC_SUB_STRING : public SUB_STRING { public: DECLARE_CONSTRUCTOR( DYNAMIC_SUB_STRING ); DECLARE_CAST_MEMBER_FUNCTION( DYNAMIC_SUB_STRING ); NONVIRTUAL BOOLEAN Copy ( IN PCGENERIC_STRING GenericString ); VIRTUAL BOOLEAN SetChAt ( IN WCHAR Char, IN CHNUM Position DEFAULT 0, IN CHNUM Length DEFAULT TO_END ); NONVIRTUAL CHNUM Truncate ( IN CHNUM Position DEFAULT 0 ); private: VOID Construct ( ); }; #endif // _DYNAMIC_SUB_STRING_