Tcl Source Code

    char flags;
#define	LONGER	01		/* prefers longer match */
#define	SHORTER	02		/* prefers shorter match */
#define	MIXED	04		/* mixed preference below */
#define	CAP	010		/* capturing parens below */
#define	BACKR	020		/* back reference below */
#define	INUSE	0100		/* in use in final tree */
#define	NOPROP	03		/* bits which may not propagate up */
#define	LMIX(f)	((f)<<2)	/* LONGER -> MIXED */
#define	SMIX(f)	((f)<<1)	/* SHORTER -> MIXED */
#define	UP(f)	(((f)&~NOPROP) | (LMIX(f) & SMIX(f) & MIXED))
#define	MESSY(f)	((f)&(MIXED|CAP|BACKR))
#define	PREF(f)	((f)&NOPROP)
#define	PREF2(f1, f2)	((PREF(f1) != 0) ? PREF(f1) : PREF(f2))
#define	COMBINE(f1, f2)	(UP((f1)|(f2)) | PREF2(f1, f2))
    short retry;		/* index into retry memory */
    int subno;			/* subexpression number (for 'b' and '(') */
    short min;			/* min repetitions, for backref only */
    short max;			/* max repetitions, for backref only */
    struct subre *left;		/* left child, if any (also freelist chain) */

#endif /* __WIN32__ && !HAVE_WINNT_IGNORE_VOID */

/*
 * Macro to use instead of "void" for arguments that must have type "void *"
 * in ANSI C; maps them to type "char *" in non-ANSI systems.
 */

#ifndef __VXWORKS__
#   ifndef NO_VOID
#	define VOID void
#   else
#	define VOID char
#   endif
#endif

/*
 * Miscellaneous declarations.
 */

#ifndef _CLIENTDATA

 * multiple of the wordsize 'sizeof(Tcl_Obj *)'. 
 */

#define WALLOCALIGN \
    (TCL_ALLOCALIGN/sizeof(Tcl_Obj *))

/*
 * wordSkip computes how many words have to be skipped until the next aligned
 * word. Note that we are only interested in the low order bits of ptr, so
 * that any possible information loss in PTR2INT is of no consequence.
 */

static inline int
wordSkip(
    void *ptr)
{
    int mask = TCL_ALLOCALIGN-1;
    int base = PTR2INT(ptr) & mask;
    return (TCL_ALLOCALIGN - base)/sizeof(Tcl_Obj *);
}

/*
 * Given a marker, compute where the following aligned memory starts. 
 */

#define MEMSTART(markerPtr)			\
    ((markerPtr) + wordSkip(markerPtr))


/*
 *----------------------------------------------------------------------
 *
 * GrowEvaluationStack --
 *

	    Tcl_Panic("STACK: Reallocating with no previous alloc");
	}
	if (needed <= 0) {
	    return MEMSTART(markerPtr);
	}
    } else {
	Tcl_Obj **tmpMarkerPtr = esPtr->tosPtr + 1;
	int offset = wordSkip(tmpMarkerPtr);

	if (needed + offset < 0) {
	    /*
	     * Put a marker pointing to the previous marker in this stack, and 
	     * store it in esPtr as the current marker. Return a pointer to
	     * the start of aligned memory.
	     */