xref: /titanic_41/usr/src/lib/libast/common/sfio/sfvscanf.c (revision fd06a699040f011e80ab8ac5213bb0a47858e69b)
1 /***********************************************************************
2 *                                                                      *
3 *               This software is part of the ast package               *
4 *           Copyright (c) 1985-2007 AT&T Knowledge Ventures            *
5 *                      and is licensed under the                       *
6 *                  Common Public License, Version 1.0                  *
7 *                      by AT&T Knowledge Ventures                      *
8 *                                                                      *
9 *                A copy of the License is available at                 *
10 *            http://www.opensource.org/licenses/cpl1.0.txt             *
11 *         (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9)         *
12 *                                                                      *
13 *              Information and Software Systems Research               *
14 *                            AT&T Research                             *
15 *                           Florham Park NJ                            *
16 *                                                                      *
17 *                 Glenn Fowler <gsf@research.att.com>                  *
18 *                  David Korn <dgk@research.att.com>                   *
19 *                   Phong Vo <kpv@research.att.com>                    *
20 *                                                                      *
21 ***********************************************************************/
22 #include	"sfhdr.h"
23 
24 /*	The main engine for reading formatted data
25 **
26 **	Written by Kiem-Phong Vo.
27 */
28 
29 #define MAXWIDTH	(int)(((uint)~0)>>1)	/* max amount to scan	*/
30 
31 /*
32  * pull in a private strtold()
33  */
34 
35 #include "sfstrtof.h"
36 
37 /* refresh stream buffer - taking care of unseekable/share streams too */
38 #if __STD_C
39 static void _sfbuf(Sfio_t* f, int* peek)
40 #else
41 static void _sfbuf(f, peek)
42 Sfio_t*	f;
43 int*	peek;
44 #endif
45 {
46 	if(f->next >= f->endb)
47 	{	if(*peek) 	/* try peeking for a share stream if possible */
48 		{	f->mode |= SF_RV;
49 			if(SFFILBUF(f,-1) > 0)
50 			{	f->mode |= SF_PEEK;
51 				return;
52 			}
53 			*peek = 0;	/* can't peek, back to normal reads */
54 		}
55 		(void)SFFILBUF(f,-1);
56 	}
57 }
58 
59 /* buffer used during scanning of a double value or a multi-byte
60    character. the fields mirror certain local variables in sfvscanf.  */
61 typedef struct _scan_s
62 {	int	error;	/* get set by _sfdscan if no value specified	*/
63 	int	inp;	/* last input character read			*/
64 	int	width;	/* field width					*/
65 	Sfio_t	*f;	/* stream being scanned				*/
66 	uchar	*d, *endd, *data;	/* local buffering system	*/
67 	int	peek;	/* != 0 if unseekable/share stream		*/
68 	int	n_input;/* number of input bytes processed		*/
69 } Scan_t;
70 
71 /* ds != 0 for scanning double values */
72 #define SCinit(sc,ds)	((sc)->inp = (sc)->error = -1, (sc)->f = f, \
73 			 ((sc)->width = (ds) ? width : -1), \
74 			 (sc)->d = d, (sc)->endd = endd, (sc)->data = data, \
75 			 (sc)->peek = peek, (sc)->n_input = n_input)
76 #define SCend(sc,ds)	(inp = (sc)->inp, f = (sc)->f, \
77 			 (width = (ds) ? (sc)->width : width), \
78 			 d = (sc)->d, endd = (sc)->endd, data = (sc)->data, \
79 			 peek = (sc)->peek, n_input = (sc)->n_input)
80 
81 #if __STD_C
82 static int _scgetc(void* arg, int flag)
83 #else
84 static int _scgetc(arg, flag)
85 void*	arg;
86 int	flag;
87 #endif
88 {
89 	Scan_t	*sc = (Scan_t*)arg;
90 
91 	if (flag)
92 	{	sc->error = flag;
93 		return 0;
94 	}
95 
96 	/* if width >= 0, do not allow to exceed width number of bytes */
97 	if(sc->width == 0)
98 	{	sc->inp = -1;
99 		return 0;
100 	}
101 
102 	if(sc->d >= sc->endd) /* refresh local buffer */
103 	{	sc->n_input += sc->d - sc->data;
104 		if(sc->peek)
105 			SFREAD(sc->f, sc->data, sc->d - sc->data);
106 		else	sc->f->next = sc->d;
107 
108 		_sfbuf(sc->f, &sc->peek);
109 		sc->data = sc->d = sc->f->next;
110 		sc->endd = sc->f->endb;
111 
112 		if(sc->d >= sc->endd)
113 		{	sc->inp = -1;
114 			return 0;
115 		}
116 	}
117 
118 	if((sc->width -= 1) >= 0) /* from _sfdscan */
119 		return (sc->inp = (int)(*sc->d++));
120 	else	return ((int)(*sc->d++));
121 }
122 
123 /* structure to match characters in a character class */
124 typedef struct _accept_s
125 {	char	ok[SF_MAXCHAR];
126 	int	yes;
127 	char	*form, *endf;
128 #if _has_multibyte
129 	wchar_t	wc;
130 #endif
131 } Accept_t;
132 
133 #if __STD_C
134 static char* _sfsetclass(const char* form, Accept_t* ac, int flags)
135 #else
136 static char* _sfsetclass(form, ac, flags)
137 char*		form;	/* format string			*/
138 Accept_t*	ac;	/* values of accepted characters	*/
139 int		flags;	/* SFFMT_LONG for wchar_t		*/
140 #endif
141 {
142 	int		c, endc, n;
143 #if _has_multibyte
144 	SFMBDCL(mbs)
145 #endif
146 
147 	if(*form == '^') /* complementing this set */
148 	{	ac->yes = 0;
149 		form += 1;
150 	}
151 	else	ac->yes = 1;
152 
153 	for(c = 0; c <= SF_MAXCHAR; ++c)
154 		ac->ok[c] = !ac->yes;
155 
156 	if(*form == ']' || *form == '-') /* special first char */
157 	{	ac->ok[*form] = ac->yes;
158 		form += 1;
159 	}
160 	ac->form = (char*)form;
161 
162 	if(flags&SFFMT_LONG)
163 		SFMBCLR(&mbs);
164 	for(n = 1; *form != ']'; form += n)
165 	{	if((c = *((uchar*)form)) == 0)
166 			return NIL(char*);
167 
168 		if(*(form+1) == '-')
169 		{	endc = *((uchar*)(form+2));
170 #if _has_multibyte
171 			if(c >= 128 || endc >= 128 ) /* range must be ascii */
172 				goto one_char;
173 #endif
174 			for(; c <= endc; ++c)
175 				ac->ok[c] = ac->yes;
176 			n = 3;
177 		}
178 		else
179 		{ one_char:
180 #if _has_multibyte /* true multi-byte chars must be checked differently */
181 			if((flags&SFFMT_LONG) && (n = (int)SFMBLEN(form,&mbs)) <= 0)
182 				return NIL(char*);
183 			if(n == 1)
184 #endif
185 				ac->ok[c] = ac->yes;
186 		}
187 	}
188 
189 	ac->endf = (char*)form;
190 	return (char*)(form+1);
191 }
192 
193 #if _has_multibyte
194 #if __STD_C
195 static int _sfwaccept(wchar_t wc, Accept_t* ac)
196 #else
197 static int _sfwaccept(wc, ac)
198 wchar_t		wc;
199 Accept_t*	ac;
200 #endif
201 {
202 	int		endc, c, n;
203 	wchar_t		fwc;
204 	char		*form = ac->form;
205 	SFMBDCL(mbs)
206 
207 	SFMBCLR(&mbs);
208 	for(n = 1; *form != ']'; form += n)
209 	{	if((c = *((uchar*)form)) == 0)
210 			return 0;
211 
212 		if(*(form+1) == '-')
213 		{	endc = *((uchar*)(form+2));
214 			if(c >= 128 || endc >= 128 ) /* range must be ascii */
215 				goto one_char;
216 			n = 3;
217 		}
218 		else
219 		{ one_char:
220 			if((n = mbrtowc(&fwc, form, ac->endf-form, &mbs)) > 1 &&
221 			   wc == fwc )
222 				return ac->yes;
223 		}
224 	}
225 
226 	return !ac->yes;
227 }
228 
229 #if _has_multibyte == 1
230 #define SFgetwc(sc,wc,fmt,ac,mbs)	_sfgetwc(sc,wc,fmt,ac,(Void_t*)(mbs))
231 #else
232 #define SFgetwc(sc,wc,fmt,ac,mbs)	_sfgetwc(sc,wc,fmt,ac,NIL(Void_t*))
233 #endif
234 
235 #if __STD_C
236 static int _sfgetwc(Scan_t* sc, wchar_t* wc, int fmt, Accept_t* ac, Void_t *mbs)
237 #else
238 static int _sfgetwc(sc, wc, fmt, ac, mbs)
239 Scan_t*		sc;	/* the scanning handle		*/
240 wchar_t*	wc;	/* to return a scanned wchar_t	*/
241 int		fmt;	/* %s, %c, %[			*/
242 Accept_t*	ac;	/* accept handle for %[		*/
243 Void_t*		mbs;	/* multibyte parsing state	*/
244 #endif
245 {
246 	int	n, v;
247 	char	b[16]; /* assuming that SFMBMAX <= 16! */
248 
249 	/* shift left data so that there will be more room to back up on error.
250 	   this won't help streams with small buffers - c'est la vie! */
251 	if(sc->d > sc->f->data && (n = sc->endd - sc->d) > 0 && n < SFMBMAX)
252 	{	memcpy(sc->f->data, sc->d, n);
253 		if(sc->f->endr == sc->f->endb)
254 			sc->f->endr = sc->f->data+n;
255 		if(sc->f->endw == sc->f->endb)
256 			sc->f->endw = sc->f->data+n;
257 		sc->f->endb = sc->f->data+n;
258 		sc->d = sc->data = sc->f->data;
259 		sc->endd = sc->f->endb;
260 		if(!mbs) sc->f->endb = sc->endd; /* stop cc's "unused mbs" warning */
261 	}
262 
263 	for(n = 0; n < SFMBMAX; )
264 	{	if((v = _scgetc((Void_t*)sc, 0)) <= 0)
265 			goto no_match;
266 		else	b[n++] = v;
267 
268 		if(mbrtowc(wc, b, n, (mbstate_t*)mbs) == (size_t)(-1))
269 			goto no_match;  /* malformed multi-byte char */
270 		else
271 		{	/* multi-byte char converted successfully */
272 			if(fmt == 'c')
273 				return 1;
274 			else if(fmt == 's')
275 			{	if(n > 1 || (n == 1 && !isspace(b[0]) ) )
276 					return 1;
277 				else	goto no_match;
278 			}
279 			else if(fmt == '[')
280 			{	if((n == 1 && ac->ok[b[0]]) ||
281 				   (n  > 1 && _sfwaccept(*wc,ac)) )
282 					return 1;
283 				else	goto no_match;
284 			}
285 			else /* if(fmt == '1') match a single wchar_t */
286 			{	if(*wc == ac->wc)
287 					return 1;
288 				else	goto no_match;
289 			}
290 		}
291 	}
292 
293 no_match: /* this unget is lossy on a stream with small buffer */
294 	if((sc->d -= n) < sc->data)
295 		sc->d = sc->data;
296 	return 0;
297 }
298 #endif /*_has_multibyte*/
299 
300 
301 #if __STD_C
302 int sfvscanf(Sfio_t* f, reg const char* form, va_list args)
303 #else
304 int sfvscanf(f,form,args)
305 Sfio_t*		f;		/* file to be scanned */
306 reg char*	form;		/* scanning format */
307 va_list		args;
308 #endif
309 {
310 	reg int		inp, shift, base, width;
311 	ssize_t		size;
312 	int		fmt, flags, dot, n_assign, v, n, n_input;
313 	char		*sp;
314 
315 	Accept_t	acc;
316 
317 	Argv_t		argv;
318 	Sffmt_t		*ft;
319 	Fmt_t		*fm, *fmstk;
320 
321 	Fmtpos_t*	fp;
322 	char		*oform;
323 	va_list		oargs;
324 	int		argp, argn;
325 
326 	int		decimal = 0, thousand = 0;
327 
328 #if _has_multibyte
329 	wchar_t		wc;
330 	SFMBDCL(fmbs)
331 	SFMBDCL(mbs)
332 #endif
333 
334 	Void_t*		value;	/* location to assign scanned value */
335 	char*		t_str;
336 	ssize_t		n_str;
337 
338 	/* local buffering system */
339 	Scan_t		scd;
340 	uchar		*d, *endd, *data;
341 	int		peek;
342 #define SFbuf(f)	(_sfbuf(f,&peek), (data = d = f->next), (endd = f->endb) )
343 #define SFlen(f)	(d - data)
344 #define SFinit(f)	((peek = f->extent < 0 && (f->flags&SF_SHARE)), SFbuf(f) )
345 #define SFend(f)	((n_input += SFlen(f)), \
346 			 (peek ? SFREAD(f,(Void_t*)data,SFlen(f)) : ((f->next = d),0)) )
347 #define SFgetc(f,c)	((c) = (d < endd || (SFend(f), SFbuf(f), d < endd)) ? \
348 				(int)(*d++) : -1 )
349 #define SFungetc(f,c)	(d -= 1)
350 
351 	SFCVINIT();	/* initialize conversion tables */
352 
353 	SFMTXSTART(f,-1);
354 
355 	if(!form || f->mode != SF_READ && _sfmode(f,SF_READ,0) < 0)
356 		SFMTXRETURN(f, -1);
357 	SFLOCK(f,0);
358 
359 	SFinit(f); /* initialize local buffering system */
360 
361 	n_assign = n_input = 0; inp = -1;
362 
363 	fmstk = NIL(Fmt_t*);
364 	ft = NIL(Sffmt_t*);
365 
366 	fp = NIL(Fmtpos_t*);
367 	argn = -1;
368 	oform = (char*)form;
369 	va_copy(oargs,args);
370 
371 	SFSETLOCALE(&decimal, &thousand);
372 
373 loop_fmt:
374 	SFMBCLR(&fmbs);
375 	while((fmt = *form++))
376 	{	if(fmt != '%')
377 		{	if(isspace(fmt))
378 			{	if(fmt != '\n' || !(f->flags&SF_LINE))
379 					fmt = -1;
380 				for(;;)
381 				{	if(SFgetc(f,inp) < 0 || inp == fmt)
382 						goto loop_fmt;
383 					else if(!isspace(inp))
384 					{	SFungetc(f,inp);
385 						goto loop_fmt;
386 					}
387 				}
388 			}
389 			else
390 			{ match_1:
391 #if _has_multibyte
392 				if((n = (int)mbrtowc(&wc,form-1,SFMBMAX,&fmbs)) <= 0)
393 					goto pop_fmt;
394 				if(n > 1)
395 				{	acc.wc = wc;
396 					SCinit(&scd,0); SFMBCLR(&mbs);
397 					v = SFgetwc(&scd, &wc, '1', &acc, &mbs);
398 					SCend(&scd,0);
399 					if(v == 0)
400 						goto pop_fmt;
401 					form += n-1;
402 				}
403 				else
404 #endif
405 				if(SFgetc(f,inp) != fmt)
406 				{	if(inp < 0)
407 						goto done;
408 					SFungetc(f,inp);
409 					goto pop_fmt;
410 				}
411 			}
412 			continue;
413 		}
414 
415 		if(*form == '%')
416 		{	form += 1;
417 			goto match_1;
418 		}
419 
420 		if(*form == '\0')
421 			goto pop_fmt;
422 
423 		if(*form == '*')
424 		{	flags = SFFMT_SKIP;
425 			form += 1;
426 		}
427 		else	flags = 0;
428 
429 		/* matching some pattern */
430 		base = 10; size = -1;
431 		width = dot = 0;
432 		t_str = NIL(char*); n_str = 0;
433 		value = NIL(Void_t*);
434 		argp = -1;
435 
436 	loop_flags:	/* LOOP FOR FLAGS, WIDTH, BASE, TYPE */
437 		switch((fmt = *form++) )
438 		{
439 		case LEFTP : /* get the type which is enclosed in balanced () */
440 			t_str = (char*)form;
441 			for(v = 1;;)
442 			{	switch(*form++)
443 				{
444 				case 0 :	/* not balanceable, retract */
445 					form = t_str;
446 					t_str = NIL(char*);
447 					n_str = 0;
448 					goto loop_flags;
449 				case LEFTP :	/* increasing nested level */
450 					v += 1;
451 					continue;
452 				case RIGHTP :	/* decreasing nested level */
453 					if((v -= 1) != 0)
454 						continue;
455 					if(*t_str != '*' )
456 						n_str = (form-1) - t_str;
457 					else
458 					{	t_str = (*_Sffmtintf)(t_str+1,&n);
459 						if(*t_str == '$')
460 						{	if(!fp &&
461 							   !(fp = (*_Sffmtposf)
462 								  (f,oform,oargs,ft,1)) )
463 								goto pop_fmt;
464 							n = FP_SET(n,argn);
465 						}
466 						else	n = FP_SET(-1,argn);
467 
468 						if(fp)
469 						{	t_str = fp[n].argv.s;
470 							n_str = fp[n].ft.size;
471 						}
472 						else if(ft && ft->extf )
473 						{	FMTSET(ft, form,args,
474 								LEFTP, 0, 0, 0,0,0,
475 								NIL(char*),0);
476 							n = (*ft->extf)
477 							      (f,(Void_t*)&argv,ft);
478 							if(n < 0)
479 								goto pop_fmt;
480 							if(!(ft->flags&SFFMT_VALUE) )
481 								goto t_arg;
482 							if((t_str = argv.s) &&
483 							   (n_str = (int)ft->size) < 0)
484 								n_str = strlen(t_str);
485 						}
486 						else
487 						{ t_arg:
488 							if((t_str = va_arg(args,char*)) )
489 								n_str = strlen(t_str);
490 						}
491 					}
492 					goto loop_flags;
493 				}
494 			}
495 
496 		case '#' : /* alternative format */
497 			flags |= SFFMT_ALTER;
498 			goto loop_flags;
499 
500 		case '.' : /* width & base */
501 			dot += 1;
502 			if(isdigit(*form))
503 			{	fmt = *form++;
504 				goto dot_size;
505 			}
506 			else if(*form == '*')
507 			{	form = (*_Sffmtintf)(form+1,&n);
508 				if(*form == '$')
509 				{	form += 1;
510 					if(!fp &&
511 					   !(fp = (*_Sffmtposf)(f,oform,oargs,ft,1)) )
512 						goto pop_fmt;
513 					n = FP_SET(n,argn);
514 				}
515 				else	n = FP_SET(-1,argn);
516 
517 				if(fp)
518 					v = fp[n].argv.i;
519 				else if(ft && ft->extf )
520 				{	FMTSET(ft, form,args, '.',dot, 0, 0,0,0,
521 						NIL(char*), 0);
522 					if((*ft->extf)(f, (Void_t*)(&argv), ft) < 0)
523 						goto pop_fmt;
524 					if(ft->flags&SFFMT_VALUE)
525 						v = argv.i;
526 					else	v = (dot <= 2) ? va_arg(args,int) : 0;
527 				}
528 				else	v = (dot <= 2) ? va_arg(args,int) : 0;
529 				if(v < 0)
530 					v = 0;
531 				goto dot_set;
532 			}
533 			else	goto loop_flags;
534 
535 		case '0' : case '1' : case '2' : case '3' : case '4' :
536 		case '5' : case '6' : case '7' : case '8' : case '9' :
537 		dot_size :
538 			for(v = fmt-'0'; isdigit(*form); ++form)
539 				v = v*10 + (*form - '0');
540 
541 			if(*form == '$')
542 			{	form += 1;
543 				if(!fp && !(fp = (*_Sffmtposf)(f,oform,oargs,ft,1)) )
544 					goto pop_fmt;
545 				argp = v-1;
546 				goto loop_flags;
547 			}
548 
549 		dot_set :
550 			if(dot == 0 || dot == 1)
551 				width = v;
552 			else if(dot == 2)
553 				base = v;
554 			goto loop_flags;
555 
556 		case 'I' : /* object size */
557 			size = -1; flags = (flags & ~SFFMT_TYPES) | SFFMT_IFLAG;
558 			if(isdigit(*form))
559 			{	for(size = 0, n = *form; isdigit(n); n = *++form)
560 					size = size*10 + (n - '0');
561 			}
562 			else if(*form == '*')
563 			{	form = (*_Sffmtintf)(form+1,&n);
564 				if(*form == '$')
565 				{	form += 1;
566 					if(!fp &&
567 					   !(fp = (*_Sffmtposf)(f,oform,oargs,ft,1)))
568 						goto pop_fmt;
569 					n = FP_SET(n,argn);
570 				}
571 				else	n = FP_SET(-1,argn);
572 
573 				if(fp)	/* use position list */
574 					size = fp[n].argv.i;
575 				else if(ft && ft->extf )
576 				{	FMTSET(ft, form,args, 'I',sizeof(int), 0, 0,0,0,
577 						NIL(char*), 0);
578 					if((*ft->extf)(f, (Void_t*)(&argv), ft) < 0)
579 						goto pop_fmt;
580 					if(ft->flags&SFFMT_VALUE)
581 						size = argv.i;
582 					else	size = va_arg(args,int);
583 				}
584 				else	size = va_arg(args,int);
585 			}
586 			goto loop_flags;
587 
588 		case 'l' :
589 			size = -1; flags &= ~SFFMT_TYPES;
590 			if(*form == 'l')
591 			{	form += 1;
592 				flags |= SFFMT_LLONG;
593 			}
594 			else	flags |= SFFMT_LONG;
595 			goto loop_flags;
596 		case 'h' :
597 			size = -1; flags &= ~SFFMT_TYPES;
598 			if(*form == 'h')
599 			{	form += 1;
600 				flags |= SFFMT_SSHORT;
601 			}
602 			else	flags |= SFFMT_SHORT;
603 			goto loop_flags;
604 		case 'L' :
605 			size = -1; flags = (flags&~SFFMT_TYPES) | SFFMT_LDOUBLE;
606 			goto loop_flags;
607 		case 'j' :
608 			size = -1; flags = (flags&~SFFMT_TYPES) | SFFMT_JFLAG;
609 			goto loop_flags;
610 		case 'z' :
611 			size = -1; flags = (flags&~SFFMT_TYPES) | SFFMT_ZFLAG;
612 			goto loop_flags;
613 		case 't' :
614 			size = -1; flags = (flags&~SFFMT_TYPES) | SFFMT_TFLAG;
615 			goto loop_flags;
616 		case QUOTE :
617 			if(thousand > 0)
618 				flags |= SFFMT_THOUSAND;
619 			goto loop_flags;
620 		}
621 
622 		/* set object size for scalars */
623 		if(flags & SFFMT_TYPES)
624 		{	if((_Sftype[fmt]&(SFFMT_INT|SFFMT_UINT)) || fmt == 'n')
625 			{	if(flags&SFFMT_LONG)
626 					size = sizeof(long);
627 				else if(flags&SFFMT_SHORT)
628 					size = sizeof(short);
629 				else if(flags&SFFMT_SSHORT)
630 					size = sizeof(char);
631 				else if(flags&SFFMT_TFLAG)
632 					size = sizeof(ptrdiff_t);
633 				else if(flags&SFFMT_ZFLAG)
634 					size = sizeof(size_t);
635 				else if(flags&(SFFMT_LLONG|SFFMT_JFLAG) )
636 					size = sizeof(Sflong_t);
637 				else if(flags&SFFMT_IFLAG)
638 				{	if(size <= 0 ||
639 					   size == sizeof(Sflong_t)*CHAR_BIT )
640 						size = sizeof(Sflong_t);
641 				}
642 				else if(size < 0)
643 					size = sizeof(int);
644 			}
645 			else if(_Sftype[fmt]&SFFMT_FLOAT)
646 			{	if(flags&(SFFMT_LONG|SFFMT_LLONG))
647 					size = sizeof(double);
648 				else if(flags&SFFMT_LDOUBLE)
649 					size = sizeof(Sfdouble_t);
650 				else if(flags&SFFMT_IFLAG)
651 				{	if(size <= 0)
652 						size = sizeof(Sfdouble_t);
653 				}
654 				else if(size < 0)
655 					size = sizeof(float);
656 			}
657 			else if(_Sftype[fmt]&SFFMT_CHAR)
658 			{
659 #if _has_multibyte
660 				if((flags&SFFMT_LONG) || fmt == 'C')
661 				{	size = sizeof(wchar_t) > sizeof(int) ?
662 						sizeof(wchar_t) : sizeof(int);
663 				} else
664 #endif
665 				if(size < 0)
666 					size = sizeof(int);
667 			}
668 		}
669 
670 		argp = FP_SET(argp,argn);
671 		if(fp)
672 		{	if(!(fp[argp].ft.flags&SFFMT_SKIP) )
673 			{	n_assign += 1;
674 				value = fp[argp].argv.vp;
675 				size = fp[argp].ft.size;
676 				if(ft && ft->extf && fp[argp].ft.fmt != fp[argp].fmt)
677 					fmt = fp[argp].ft.fmt;
678 			}
679 			else	flags |= SFFMT_SKIP;
680 		}
681 		else if(ft && ft->extf)
682 		{	FMTSET(ft, form,args, fmt, size,flags, width,0,base, t_str,n_str);
683 			SFend(f); SFOPEN(f,0);
684 			v = (*ft->extf)(f, (Void_t*)&argv, ft);
685 			SFLOCK(f,0); SFbuf(f);
686 
687 			if(v < 0)
688 				goto pop_fmt;
689 			else if(v > 0) /* extf comsumed v input bytes */
690 			{	n_input += v;
691 				if(!(ft->flags&SFFMT_SKIP) )
692 					n_assign += 1;
693 				continue;
694 			}
695 			else /* if(v == 0): extf did not use input stream */
696 			{	FMTGET(ft, form,args, fmt, size, flags, width,n,base);
697 
698 				if((ft->flags&SFFMT_VALUE) && !(ft->flags&SFFMT_SKIP) )
699 					value = argv.vp;
700 			}
701 		}
702 
703 		if(_Sftype[fmt] == 0) /* unknown pattern */
704 			goto pop_fmt;
705 
706 		if(fmt == '!')
707 		{	if(!fp)
708 				fp = (*_Sffmtposf)(f,oform,oargs,ft,1);
709 			else	goto pop_fmt;
710 
711 			if(!(argv.ft = va_arg(args,Sffmt_t*)) )
712 				continue;
713 			if(!argv.ft->form && ft ) /* change extension functions */
714 			{	if(ft->eventf &&
715 				   (*ft->eventf)(f,SF_DPOP,(Void_t*)form,ft) < 0)
716 					continue;
717 				fmstk->ft = ft = argv.ft;
718 			}
719 			else			/* stack a new environment */
720 			{	if(!(fm = (Fmt_t*)malloc(sizeof(Fmt_t))) )
721 					goto done;
722 
723 				ft = fm->ft = argv.ft;
724 				SFMBSET(ft->mbs, &fmbs);
725 				if(ft->form)
726 				{	fm->form = (char*)form; SFMBCPY(&fm->mbs,&fmbs);
727 					va_copy(fm->args,args);
728 
729 					fm->oform = oform;
730 					va_copy(fm->oargs,oargs);
731 					fm->argn = argn;
732 					fm->fp = fp;
733 
734 					form = ft->form; SFMBCLR(ft->mbs);
735 					va_copy(args,ft->args);
736 					argn = -1;
737 					fp = NIL(Fmtpos_t*);
738 					oform = (char*)form;
739 					va_copy(oargs,args);
740 				}
741 				else	fm->form = NIL(char*);
742 
743 				fm->eventf = ft->eventf;
744 				fm->next = fmstk;
745 				fmstk = fm;
746 			}
747 			continue;
748 		}
749 
750 		/* get the address to assign value */
751 		if(!value && !(flags&SFFMT_SKIP) )
752 			value = va_arg(args,Void_t*);
753 
754 		if(fmt == 'n') /* return length of consumed input */
755 		{
756 #if !_ast_intmax_long
757 			if(size == sizeof(Sflong_t) )
758 				*((Sflong_t*)value) = (Sflong_t)(n_input+SFlen(f));
759 			else
760 #endif
761 			if(size == sizeof(long) )
762 				*((long*)value) = (long)(n_input+SFlen(f));
763 			else if(size == sizeof(short) )
764 				*((short*)value) = (short)(n_input+SFlen(f));
765 			else if(size == sizeof(uchar))
766 				*((uchar*)value) = (uchar)(n_input+SFlen(f));
767 			else	*((int*)value) = (int)(n_input+SFlen(f));
768 			continue;
769 		}
770 
771 		/* if get here, start scanning input */
772 		if(width == 0)
773 			width = fmt == 'c' ? 1 : MAXWIDTH;
774 
775 		/* define the first input character */
776 		if(fmt == 'c' || fmt == '[' || fmt == 'C' )
777 			SFgetc(f,inp);
778 		else
779 		{	do	{ SFgetc(f,inp); }
780 			while(isspace(inp)); /* skip starting blanks */
781 		}
782 		if(inp < 0)
783 			goto done;
784 
785 		if(_Sftype[fmt] == SFFMT_FLOAT)
786 		{	SFungetc(f,inp); SCinit(&scd,1);
787 			argv.ld = _sfdscan((Void_t*)(&scd), _scgetc);
788 			SCend(&scd,1);
789 
790 			if(scd.error >= 0)
791 			{	if(inp >= 0)
792 					SFungetc(f, inp);
793 				goto pop_fmt;
794 			}
795 
796 			if(value)
797 			{
798 #if !_ast_fltmax_double
799 				if(size == sizeof(Sfdouble_t))
800 					*((Sfdouble_t*)value) = argv.ld;
801 				else
802 #endif
803 				if(size == sizeof(double))
804 					*((double*)value) = (double)argv.ld;
805 				else	*((float*)value) = (float)argv.ld;
806 
807 				n_assign += 1;
808 			}
809 		}
810 		else if(_Sftype[fmt] == SFFMT_UINT || fmt == 'p')
811 		{	if(inp == '-')
812 			{	SFungetc(f,inp);
813 				goto pop_fmt;
814 			}
815 			else	goto int_cvt;
816 		}
817 		else if(_Sftype[fmt] == SFFMT_INT)
818 		{ int_cvt:
819 			if(inp == '-' || inp == '+')
820 			{	if(inp == '-')
821 					flags |= SFFMT_MINUS;
822 				while(--width > 0 && SFgetc(f,inp) >= 0)
823 					if(!isspace(inp))
824 						break;
825 			}
826 			if(inp < 0)
827 				goto done;
828 
829 			if(fmt == 'o')
830 				base = 8;
831 			else if(fmt == 'x' || fmt == 'X' || fmt == 'p')
832 				base = 16;
833 			else if(fmt == 'i' && inp == '0') /* self-described data */
834 			{	base = 8;
835 				if(width > 1) /* peek to see if it's a base-16 */
836 				{	if(SFgetc(f,inp) >= 0)
837 					{	if(inp == 'x' || inp == 'X')
838 							base = 16;
839 						SFungetc(f,inp);
840 					}
841 					inp = '0';
842 				}
843 			}
844 
845 			/* now convert */
846 			argv.lu = 0;
847 			if(base == 16)
848 			{	sp = (char*)_Sfcv36;
849 				shift = 4;
850 				if(sp[inp] >= 16)
851 				{	SFungetc(f,inp);
852 					goto pop_fmt;
853 				}
854 				if(inp == '0' && --width > 0)
855 				{	/* skip leading 0x or 0X */
856 					if(SFgetc(f,inp) >= 0 &&
857 					   (inp == 'x' || inp == 'X') && --width > 0)
858 						SFgetc(f,inp);
859 				}
860 				if(inp >= 0 && sp[inp] < 16)
861 					goto base_shift;
862 			}
863 			else if(base == 10)
864 			{	for(n = v = 0;; )
865 				{	/* fast base 10 conversion */
866 #define TEN(x) (((x) << 3) + ((x) << 1) )
867 					if (inp >= '0' && inp <= '9')
868 					{	argv.lu = TEN(argv.lu) + (inp-'0');
869 						n += 1;
870 					}
871 					else if(inp == thousand)
872 					{	if((v && n != 3) || (!v && n > 3) )
873 							break;
874 						v = 1; n = 0;
875 					}
876 					else	break;
877 					if((width -= 1) <= 0 || SFgetc(f,inp) < 0)
878 						break;
879 				}
880 				if (!n && !v)
881 				{	SFungetc(f,inp);
882 					goto pop_fmt;
883 				}
884 
885 				if(fmt == 'i' && inp == '#' && !(flags&SFFMT_ALTER) )
886 				{	base = (int)argv.lu;
887 					if(base < 2 || base > SF_RADIX)
888 						goto pop_fmt;
889 					argv.lu = 0;
890 					sp = (char*)(base <= 36 ? _Sfcv36 : _Sfcv64);
891 					if(--width > 0 &&
892 					   SFgetc(f,inp) >= 0 && sp[inp] < base)
893 						goto base_conv;
894 				}
895 			}
896 			else
897 			{	/* other bases */
898 				sp = (char*)(base <= 36 ? _Sfcv36 : _Sfcv64);
899 				if(base < 2 || base > SF_RADIX || sp[inp] >= base)
900 				{	SFungetc(f,inp);
901 					goto pop_fmt;
902 				}
903 
904 			base_conv: /* check for power of 2 conversions */
905 				if((base & ~(base-1)) == base)
906 				{	if(base < 8)
907 						shift = base <  4 ? 1 : 2;
908 					else if(base < 32)
909 						shift = base < 16 ? 3 : 4;
910 					else	shift = base < 64 ? 5 : 6;
911 
912 			base_shift:	do
913 					{ argv.lu = (argv.lu << shift) + sp[inp];
914 					} while(--width > 0 &&
915 					        SFgetc(f,inp) >= 0 && sp[inp] < base);
916 				}
917 				else
918 				{	do
919 					{ argv.lu = (argv.lu * base) + sp[inp];
920 					} while(--width > 0 &&
921 						SFgetc(f,inp) >= 0 && sp[inp] < base);
922 				}
923 			}
924 
925 			if(flags&SFFMT_MINUS)
926 				argv.ll = -argv.ll;
927 
928 			if(value)
929 			{	n_assign += 1;
930 
931 				if(fmt == 'p')
932 #if _more_void_int
933 					*((Void_t**)value) = (Void_t*)((ulong)argv.lu);
934 #else
935 					*((Void_t**)value) = (Void_t*)((uint)argv.lu);
936 #endif
937 #if !_ast_intmax_long
938 				else if(size == sizeof(Sflong_t))
939 					*((Sflong_t*)value) = argv.ll;
940 #endif
941 				else if(size == sizeof(long))
942 				{	if(fmt == 'd' || fmt == 'i')
943 						*((long*)value) = (long)argv.ll;
944 					else	*((ulong*)value) = (ulong)argv.lu;
945 				}
946 				else if(size == sizeof(short))
947 				{	if(fmt == 'd' || fmt == 'i')
948 						*((short*)value) = (short)argv.ll;
949 					else	*((ushort*)value) = (ushort)argv.lu;
950 				}
951 				else if(size == sizeof(char) )
952 				{	if(fmt == 'd' || fmt == 'i')
953 						*((char*)value) = (char)argv.ll;
954 					else	*((uchar*)value) = (uchar)argv.lu;
955 				}
956 				else
957 				{	if(fmt == 'd' || fmt == 'i')
958 						*((int*)value) = (int)argv.ll;
959 					else	*((uint*)value) = (uint)argv.lu;
960 				}
961 			}
962 		}
963 		else if(fmt == 'C' || fmt == 'S')
964 		{	fmt = fmt == 'C' ? 'c' : 's';
965 			flags = (flags & ~SFFMT_TYPES) | SFFMT_LONG;
966 			goto do_string;
967 		}
968 		else if(fmt == 's' || fmt == 'c' || fmt == '[' )
969 		{ do_string:
970 			if(value)
971 			{	if(size < 0)
972 					size = MAXWIDTH;
973 				if(fmt != 'c')
974 					size -= 1;
975 #if _has_multibyte
976 				if(flags&SFFMT_LONG)
977 					argv.ws = (wchar_t*)value;
978 				else
979 #endif
980 					argv.s = (char*)value;
981 			}
982 			else	size = 0;
983 
984 			if(fmt == '[' && !(form = _sfsetclass(form,&acc,flags)) )
985 			{	SFungetc(f,inp);
986 				goto pop_fmt;
987 			}
988 
989 			n = 0; /* count number of scanned characters */
990 #if _has_multibyte
991 			if(flags&SFFMT_LONG)
992 			{	SFungetc(f,inp); SCinit(&scd,0); SFMBCLR(&mbs);
993 				for(; width > 0; --width)
994 				{	if(SFgetwc(&scd,&wc,fmt,&acc,&mbs) == 0)
995 						break;
996 					if((n += 1) <= size)
997 						*argv.ws++ = wc;
998 				}
999 				SCend(&scd,0);
1000 			}
1001 			else
1002 #endif
1003 
1004 			if(fmt == 's')
1005 			{	do
1006 				{	if(isspace(inp))
1007 						break;
1008 					if((n += 1) <= size)
1009 						*argv.s++ = inp;
1010 				} while(--width > 0 && SFgetc(f,inp) >= 0);
1011 			}
1012 			else if(fmt == 'c')
1013 			{	do
1014 			 	{	if((n += 1) <= size)
1015 						*argv.s++ = inp;
1016 				} while(--width > 0 && SFgetc(f,inp) >= 0);
1017 			}
1018 			else /* if(fmt == '[') */
1019 			{	do
1020 				{	if(!acc.ok[inp])
1021 					{	if(n > 0 || (flags&SFFMT_ALTER) )
1022 							break;
1023 						else
1024 						{	SFungetc(f,inp);
1025 							goto pop_fmt;
1026 						}
1027 					}
1028 					if((n += 1) <= size)
1029 						*argv.s++ = inp;
1030 				} while(--width > 0 && SFgetc(f,inp) >= 0);
1031 			}
1032 
1033 			if(value && (n > 0 || fmt == '[') )
1034 			{	n_assign += 1;
1035 				if(fmt != 'c' && size >= 0)
1036 				{
1037 #if _has_multibyte
1038 					if(flags&SFFMT_LONG)
1039 						*argv.ws = 0;
1040 					else
1041 #endif
1042 						*argv.s = 0;
1043 				}
1044 			}
1045 		}
1046 
1047 		if(width > 0 && inp >= 0)
1048 			SFungetc(f,inp);
1049 	}
1050 
1051 pop_fmt:
1052 	if(fp)
1053 	{	free(fp);
1054 		fp = NIL(Fmtpos_t*);
1055 	}
1056 	while((fm = fmstk) ) /* pop the format stack and continue */
1057 	{	if(fm->eventf)
1058 		{	if(!form || !form[0])
1059 				(*fm->eventf)(f,SF_FINAL,NIL(Void_t*),ft);
1060 			else if((*fm->eventf)(f,SF_DPOP,(Void_t*)form,ft) < 0)
1061 				goto loop_fmt;
1062 		}
1063 
1064 		fmstk = fm->next;
1065 		if((form = fm->form) )
1066 		{	SFMBCPY(&fmbs,&fm->mbs);
1067 			va_copy(args, fm->args);
1068 			oform = fm->oform;
1069 			va_copy(oargs,fm->oargs);
1070 			argn = fm->argn;
1071 			fp = fm->fp;
1072 		}
1073 		ft = fm->ft;
1074 		free(fm);
1075 		if(form && form[0])
1076 			goto loop_fmt;
1077 	}
1078 
1079 done:
1080 	if(fp)
1081 		free(fp);
1082 	while((fm = fmstk) )
1083 	{	if(fm->eventf)
1084 			(*fm->eventf)(f,SF_FINAL,NIL(Void_t*),fm->ft);
1085 		fmstk = fm->next;
1086 		free(fm);
1087 	}
1088 
1089 	SFend(f);
1090 
1091 	SFOPEN(f,0);
1092 
1093 	if(n_assign == 0 && inp < 0)
1094 		n_assign = -1;
1095 
1096 	SFMTXRETURN(f,n_assign);
1097 }
1098