antlr3commontree.h

antlr最新版本V3源代码

/** Interface for an ANTLR3 common tree which is what gets
 *  passed around by the AST producing parser.
 */

#ifndef	_ANTLR3_COMMON_TREE_H
#define	_ANTLR3_COMMON_TREE_H

#include    <antlr3defs.h>
#include    <antlr3basetree.h>
#include    <antlr3commontoken.h>

typedef struct ANTLR3_COMMON_TREE_struct
{

   /* Not used by ANTLR, but if a super structure is created above
     * this structure, it can be used to point to the start of the super
     * structure, where additional data and function pointers can be stored.
     */
    void	* super;

    /** Start token index that encases this tree
     */
    ANTLR3_UINT64   startIndex;

    /** End token that encases this tree
     */
    ANTLR3_UINT64   stopIndex;

    /** A single token, this is the payload for the tree
     */
    pANTLR3_COMMON_TOKEN    token;

    /** Inidicates whether this token was created by the Arboretum or
     *  is a stand alone structure that we must free.
     */
    ANTLR3_BOOLEAN	    factoryMade;

    /* An encapsulated BASE TREE strcuture (NOT a pointer)
     * that perfoms a lot of the dirty work of node management
     * To this we add just a few functions that are specific to the 
     * payload. You can further abstract common treeso long
     * as you alwys have a baseTree pointer in the top structure
     * and copy it from the next one down. 
     * So, lets say we have a structure JIMS_TREE. 
     * It needs an ANTLR3_BASE_TREE that will support all the
     * general tree duplication stuff.
     * It needs a ANTLR3_COMMON_TREE structure embedded or completely
     * provides the equivalent interface.
     * It provides it's own methods and data.
     * To create a new one of these, the function provided to
     * the tree adaptor (see comments there) should allocate the
     * memory for a new JIMS_TREE structure, then call
     * antlr3InitCommonTree(<addressofembeddedCOMMON_TREE>)
     * antlr3BaseTreeNew(<addressofBASETREE>)
     * The interfaces for BASE_TREE and COMMON_TREE will then
     * be initialized. You then call and you can override them or just init
     * JIMS_TREE (note that the basetree in common tree will be ignored)
     * just the top level basetree is used). Codegen will take care of the rest.
     * 
     */
    ANTLR3_BASE_TREE	    baseTree;

    pANTLR3_COMMON_TOKEN    (*getToken)			(pANTLR3_BASE_TREE base);       
 
}
    ANTLR3_COMMON_TREE;

/** \brief ANTLR3 Token factory interface to create lots of tokens efficiently
 *  rather than creating and freeing lots of little bits of memory.
 */
typedef	struct ANTLR3_ARBORETUM_struct
{
    /** Pointers to the array of tokens that this factory has produced so far
     */
    pANTLR3_COMMON_TREE    *pools;

    /** Current pool tokens we are allocating from
     */
    ANTLR3_INT32	    thisPool;

    /** The next token to throw out from the pool, will cause a new pool allocation
     *  if this exceeds the available tokenCount
     */
    ANTLR3_UINT32	    nextTree;

    /** Trick to initialize tokens and their API quickly, we set up this token when the
     *  factory is created, then just copy the memory it uses into the new token.
     */
    ANTLR3_COMMON_TREE	    unTruc;

    /** Pointer to a function that returns a new tree
     */
    pANTLR3_BASE_TREE	    (*newTree)		(struct ANTLR3_ARBORETUM_struct * factory);
    pANTLR3_BASE_TREE	    (*newFromTree)	(struct ANTLR3_ARBORETUM_struct * factory, pANTLR3_COMMON_TREE tree);
    pANTLR3_BASE_TREE	    (*newFromToken)	(struct ANTLR3_ARBORETUM_struct * factory, pANTLR3_COMMON_TOKEN token);

    /** Pointer to a function the destroys the factory
     */
    void		    (*close)	    (struct ANTLR3_ARBORETUM_struct * factory);
}
    ANTLR3_ARBORETUM;

#endif