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/* Copyright (c) 1986 Regents of the University of California */ |
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|
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#ifndef lint |
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static char SCCSid[] = "$SunId$ LBL"; |
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#endif |
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|
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/* |
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* Routines for tracking object modifiers |
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*/ |
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|
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#include "standard.h" |
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|
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#include "object.h" |
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|
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|
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extern int (*addobjnotify[])(); /* people to notify of new objects */ |
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|
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static struct ohtab { |
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int hsiz; /* current table size */ |
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OBJECT *htab; /* table, if allocated */ |
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} modtab = {100, NULL}, objtab = {1000, NULL}; /* modifiers and objects */ |
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|
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|
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#ifdef GETOBJ |
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int |
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object(oname) /* get an object number from its name */ |
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char *oname; |
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{ |
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register int ndx; |
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|
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ndx = otndx(oname, &objtab); |
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return(objtab.htab[ndx]); |
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} |
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#endif |
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|
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|
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int |
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modifier(mname) /* get a modifier number from its name */ |
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char *mname; |
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{ |
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register int ndx; |
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|
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ndx = otndx(mname, &modtab); |
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return(modtab.htab[ndx]); |
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} |
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|
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|
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insertobject(obj) /* insert new object into our list */ |
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register OBJECT obj; |
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{ |
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register int i; |
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|
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#ifdef GETOBJ |
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i = otndx(objptr(obj)->oname, &objtab); |
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objtab.htab[i] = obj; |
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#endif |
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if (ismodifier(objptr(obj)->otype)) { |
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i = otndx(objptr(obj)->oname, &modtab); |
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modtab.htab[i] = obj; |
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} |
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for (i = 0; addobjnotify[i] != NULL; i++) |
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(*addobjnotify[i])(obj); |
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} |
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|
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|
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static int |
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nexthsiz(oldsiz) /* return next hash table size */ |
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int oldsiz; |
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{ |
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static int hsiztab[] = { |
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251, 509, 1021, 2039, 4093, 8191, 16381, 0 |
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}; |
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register int *hsp; |
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|
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for (hsp = hsiztab; *hsp; hsp++) |
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if (*hsp > oldsiz) |
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return(*hsp); |
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return(oldsiz*2 + 1); /* not always prime */ |
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} |
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|
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|
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static int |
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shash(s) /* hash a string */ |
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register char *s; |
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{ |
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register int h = 0; |
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|
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while (*s) |
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h = (h<<1 & 0x7fff) ^ *s++; |
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return(h); |
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} |
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|
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|
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static int |
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otndx(name, tab) /* get object table index for name */ |
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char *name; |
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register struct ohtab *tab; |
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{ |
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OBJECT *oldhtab; |
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int hval, i; |
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register int ndx; |
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|
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if (tab->htab == NULL) { /* new table */ |
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tab->hsiz = nexthsiz(tab->hsiz); |
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tab->htab = (OBJECT *)malloc(tab->hsiz*sizeof(OBJECT)); |
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if (tab->htab == NULL) |
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error(SYSTEM, "out of memory in otndx"); |
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ndx = tab->hsiz; |
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while (ndx--) /* empty it */ |
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tab->htab[ndx] = OVOID; |
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} |
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/* look up object */ |
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hval = shash(name); |
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tryagain: |
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for (i = 0; i < tab->hsiz; i++) { |
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ndx = (hval + i*i) % tab->hsiz; |
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if (tab->htab[ndx] == OVOID || |
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!strcmp(objptr(tab->htab[ndx])->oname, name)) |
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return(ndx); |
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} |
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/* table is full, reallocate */ |
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oldhtab = tab->htab; |
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ndx = tab->hsiz; |
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tab->htab = NULL; |
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while (ndx--) |
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if (oldhtab[ndx] != OVOID) { |
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i = otndx(objptr(oldhtab[ndx])->oname, tab); |
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tab->htab[i] = oldhtab[ndx]; |
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} |
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free((char *)oldhtab); |
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goto tryagain; /* should happen only once! */ |
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} |
