14887Schin /***********************************************************************
24887Schin * *
34887Schin * This software is part of the ast package *
4*10898Sroland.mainz@nrubsig.org * Copyright (c) 1986-2009 AT&T Intellectual Property *
54887Schin * and is licensed under the *
64887Schin * Common Public License, Version 1.0 *
78462SApril.Chin@Sun.COM * by AT&T Intellectual Property *
84887Schin * *
94887Schin * A copy of the License is available at *
104887Schin * http://www.opensource.org/licenses/cpl1.0.txt *
114887Schin * (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) *
124887Schin * *
134887Schin * Information and Software Systems Research *
144887Schin * AT&T Research *
154887Schin * Florham Park NJ *
164887Schin * *
174887Schin * Glenn Fowler <gsf@research.att.com> *
184887Schin * *
194887Schin ***********************************************************************/
204887Schin #pragma prototyped
214887Schin /*
224887Schin * Glenn Fowler
234887Schin * AT&T Research
244887Schin *
254887Schin * preprocessor context switch
264887Schin *
274887Schin * args op return
284887Schin * (0,0) free current context 0
294887Schin * (0,1) save current context current
304887Schin * (p,0) free context p 0
314887Schin * (p,1) make p current context previous
324887Schin */
334887Schin
344887Schin #include "pplib.h"
354887Schin
364887Schin void*
ppcontext(void * context,int flags)374887Schin ppcontext(void* context, int flags)
384887Schin {
394887Schin struct ppcontext* np = (struct ppcontext*)context;
404887Schin struct ppcontext* op;
414887Schin
424887Schin if (flags & 01)
434887Schin {
444887Schin if (!(op = pp.context)) op = pp.context = newof(0, struct ppcontext, 1, 0);
454887Schin memcpy(op, _PP_CONTEXT_BASE_, sizeof(struct ppcontext));
464887Schin }
474887Schin else
484887Schin {
494887Schin if (!(op = np)) op = (struct ppcontext*)_PP_CONTEXT_BASE_;
504887Schin if (op->filtab) hashfree(op->filtab);
514887Schin if (op->prdtab) hashfree(op->prdtab);
524887Schin if (op->symtab) hashfree(op->symtab);
534887Schin if (op->date) free(op->date);
544887Schin if (op->time) free(op->time);
554887Schin if (np)
564887Schin {
574887Schin free(np);
584887Schin np = 0;
594887Schin }
604887Schin memzero(op, sizeof(struct ppcontext));
614887Schin op = 0;
624887Schin }
634887Schin if (np) memcpy(_PP_CONTEXT_BASE_, np, sizeof(struct ppcontext));
644887Schin return((void*)op);
654887Schin }
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