summaryrefslogtreecommitdiff
path: root/src/stdio/vfprintf.c
blob: b5948bd2649677f1c0acfd4e292d9f8dec9484d0 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
#include "stdio_impl.h"
#include <errno.h>
#include <ctype.h>
#include <limits.h>
#include <string.h>
#include <stdarg.h>
#include <wchar.h>
#include <inttypes.h>
#include <math.h>
#include <float.h>

/* Some useful macros */

#define MAX(a,b) ((a)>(b) ? (a) : (b))
#define MIN(a,b) ((a)<(b) ? (a) : (b))
#define CONCAT2(x,y) x ## y
#define CONCAT(x,y) CONCAT2(x,y)

/* Convenient bit representation for modifier flags, which all fall
 * within 31 codepoints of the space character. */

#define ALT_FORM   (1U<<'#'-' ')
#define ZERO_PAD   (1U<<'0'-' ')
#define LEFT_ADJ   (1U<<'-'-' ')
#define PAD_POS    (1U<<' '-' ')
#define MARK_POS   (1U<<'+'-' ')
#define GROUPED    (1U<<'\''-' ')

#define FLAGMASK (ALT_FORM|ZERO_PAD|LEFT_ADJ|PAD_POS|MARK_POS|GROUPED)

#if UINT_MAX == ULONG_MAX
#define LONG_IS_INT
#endif

#if SIZE_MAX != ULONG_MAX || UINTMAX_MAX != ULLONG_MAX
#define ODD_TYPES
#endif

/* State machine to accept length modifiers + conversion specifiers.
 * Result is 0 on failure, or an argument type to pop on success. */

enum {
	BARE, LPRE, LLPRE, HPRE, HHPRE, BIGLPRE,
	ZTPRE, JPRE,
	STOP,
	PTR, INT, UINT, ULLONG,
#ifndef LONG_IS_INT
	LONG, ULONG,
#else
#define LONG INT
#define ULONG UINT
#endif
	SHORT, USHORT, CHAR, UCHAR,
#ifdef ODD_TYPES
	LLONG, SIZET, IMAX, UMAX, PDIFF, UIPTR,
#else
#define LLONG ULLONG
#define SIZET ULONG
#define IMAX LLONG
#define UMAX ULLONG
#define PDIFF LONG
#define UIPTR ULONG
#endif
	DBL, LDBL,
	NOARG,
	MAXSTATE
};

#define S(x) [(x)-'A']

static const unsigned char states[]['z'-'A'+1] = {
	{ /* 0: bare types */
		S('d') = INT, S('i') = INT,
		S('o') = UINT, S('u') = UINT, S('x') = UINT, S('X') = UINT,
		S('e') = DBL, S('f') = DBL, S('g') = DBL, S('a') = DBL,
		S('E') = DBL, S('F') = DBL, S('G') = DBL, S('A') = DBL,
		S('c') = CHAR, S('C') = INT,
		S('s') = PTR, S('S') = PTR, S('p') = UIPTR, S('n') = PTR,
		S('m') = NOARG,
		S('l') = LPRE, S('h') = HPRE, S('L') = BIGLPRE,
		S('z') = ZTPRE, S('j') = JPRE, S('t') = ZTPRE,
	}, { /* 1: l-prefixed */
		S('d') = LONG, S('i') = LONG,
		S('o') = ULONG, S('u') = ULONG, S('x') = ULONG, S('X') = ULONG,
		S('e') = DBL, S('f') = DBL, S('g') = DBL, S('a') = DBL,
		S('E') = DBL, S('F') = DBL, S('G') = DBL, S('A') = DBL,
		S('c') = INT, S('s') = PTR, S('n') = PTR,
		S('l') = LLPRE,
	}, { /* 2: ll-prefixed */
		S('d') = LLONG, S('i') = LLONG,
		S('o') = ULLONG, S('u') = ULLONG,
		S('x') = ULLONG, S('X') = ULLONG,
		S('n') = PTR,
	}, { /* 3: h-prefixed */
		S('d') = SHORT, S('i') = SHORT,
		S('o') = USHORT, S('u') = USHORT,
		S('x') = USHORT, S('X') = USHORT,
		S('n') = PTR,
		S('h') = HHPRE,
	}, { /* 4: hh-prefixed */
		S('d') = CHAR, S('i') = CHAR,
		S('o') = UCHAR, S('u') = UCHAR,
		S('x') = UCHAR, S('X') = UCHAR,
		S('n') = PTR,
	}, { /* 5: L-prefixed */
		S('e') = LDBL, S('f') = LDBL, S('g') = LDBL, S('a') = LDBL,
		S('E') = LDBL, S('F') = LDBL, S('G') = LDBL, S('A') = LDBL,
		S('n') = PTR,
	}, { /* 6: z- or t-prefixed (assumed to be same size) */
		S('d') = PDIFF, S('i') = PDIFF,
		S('o') = SIZET, S('u') = SIZET,
		S('x') = SIZET, S('X') = SIZET,
		S('n') = PTR,
	}, { /* 7: j-prefixed */
		S('d') = IMAX, S('i') = IMAX,
		S('o') = UMAX, S('u') = UMAX,
		S('x') = UMAX, S('X') = UMAX,
		S('n') = PTR,
	}
};

#define OOB(x) ((unsigned)(x)-'A' > 'z'-'A')

union arg
{
	uintmax_t i;
	long double f;
	void *p;
};

static void pop_arg(union arg *arg, int type, va_list *ap)
{
	/* Give the compiler a hint for optimizing the switch. */
	if ((unsigned)type > MAXSTATE) return;
	switch (type) {
	       case PTR:	arg->p = va_arg(*ap, void *);
	break; case INT:	arg->i = va_arg(*ap, int);
	break; case UINT:	arg->i = va_arg(*ap, unsigned int);
#ifndef LONG_IS_INT
	break; case LONG:	arg->i = va_arg(*ap, long);
	break; case ULONG:	arg->i = va_arg(*ap, unsigned long);
#endif
	break; case ULLONG:	arg->i = va_arg(*ap, unsigned long long);
	break; case SHORT:	arg->i = (short)va_arg(*ap, int);
	break; case USHORT:	arg->i = (unsigned short)va_arg(*ap, int);
	break; case CHAR:	arg->i = (signed char)va_arg(*ap, int);
	break; case UCHAR:	arg->i = (unsigned char)va_arg(*ap, int);
#ifdef ODD_TYPES
	break; case LLONG:	arg->i = va_arg(*ap, long long);
	break; case SIZET:	arg->i = va_arg(*ap, size_t);
	break; case IMAX:	arg->i = va_arg(*ap, intmax_t);
	break; case UMAX:	arg->i = va_arg(*ap, uintmax_t);
	break; case PDIFF:	arg->i = va_arg(*ap, ptrdiff_t);
	break; case UIPTR:	arg->i = (uintptr_t)va_arg(*ap, void *);
#endif
	break; case DBL:	arg->f = va_arg(*ap, double);
	break; case LDBL:	arg->f = va_arg(*ap, long double);
	}
}

static void out(FILE *f, const char *s, size_t l)
{
	__fwritex((void *)s, l, f);
}

static void pad(FILE *f, char c, int w, int l, int fl)
{
	char pad[256];
	if (fl & (LEFT_ADJ | ZERO_PAD) || l >= w) return;
	l = w - l;
	memset(pad, c, l>sizeof pad ? sizeof pad : l);
	for (; l >= sizeof pad; l -= sizeof pad)
		out(f, pad, sizeof pad);
	out(f, pad, l);
}

static const char xdigits[16] = {
	"0123456789ABCDEF"
};

static char *fmt_x(uintmax_t x, char *s, int lower)
{
	for (; x; x>>=4) *--s = xdigits[(x&15)]|lower;
	return s;
}

static char *fmt_o(uintmax_t x, char *s)
{
	for (; x; x>>=3) *--s = '0' + (x&7);
	return s;
}

static char *fmt_u(uintmax_t x, char *s)
{
	unsigned long y;
	for (   ; x>ULONG_MAX; x/=10) *--s = '0' + x%10;
	for (y=x;           y; y/=10) *--s = '0' + y%10;
	return s;
}

/* Do not override this check. The floating point printing code below
 * depends on the float.h constants being right. If they are wrong, it
 * may overflow the stack. */
#if LDBL_MANT_DIG == 53
typedef char compiler_defines_long_double_incorrectly[9-(int)sizeof(long double)];
#endif

static int fmt_fp(FILE *f, long double y, int w, int p, int fl, int t)
{
	uint32_t big[(LDBL_MAX_EXP+LDBL_MANT_DIG)/9+1];
	uint32_t *a, *d, *r, *z;
	int e2=0, e, i, j, l;
	char buf[9+LDBL_MANT_DIG/4], *s;
	const char *prefix="-0X+0X 0X-0x+0x 0x";
	int pl;
	char ebuf0[3*sizeof(int)], *ebuf=&ebuf0[3*sizeof(int)], *estr;

	pl=1;
	if (signbit(y)) {
		y=-y;
	} else if (fl & MARK_POS) {
		prefix+=3;
	} else if (fl & PAD_POS) {
		prefix+=6;
	} else prefix++, pl=0;

	if (!isfinite(y)) {
		char *s = (t&32)?"inf":"INF";
		if (y!=y) s=(t&32)?"nan":"NAN", pl=0;
		pad(f, ' ', w, 3+pl, fl&~ZERO_PAD);
		out(f, prefix, pl);
		out(f, s, 3);
		pad(f, ' ', w, 3+pl, fl^LEFT_ADJ);
		return MAX(w, 3+pl);
	}

	y = frexpl(y, &e2) * 2;
	if (y) e2--;

	if ((t|32)=='a') {
		long double round = 8.0;
		int re;

		if (t&32) prefix += 9;
		pl += 2;

		if (p<0 || p>=LDBL_MANT_DIG/4-1) re=0;
		else re=LDBL_MANT_DIG/4-1-p;

		if (re) {
			while (re--) round*=16;
			if (*prefix=='-') {
				y=-y;
				y-=round;
				y+=round;
				y=-y;
			} else {
				y+=round;
				y-=round;
			}
		}

		estr=fmt_u(e2<0 ? -e2 : e2, ebuf);
		if (estr==ebuf) *--estr='0';
		*--estr = (e2<0 ? '-' : '+');
		*--estr = t+('p'-'a');

		s=buf;
		do {
			int x=y;
			*s++=xdigits[x]|(t&32);
			y=16*(y-x);
			if (s-buf==1 && (y||p>0||(fl&ALT_FORM))) *s++='.';
		} while (y);

		if (p && s-buf-2 < p)
			l = (p+2) + (ebuf-estr);
		else
			l = (s-buf) + (ebuf-estr);

		pad(f, ' ', w, pl+l, fl);
		out(f, prefix, pl);
		pad(f, '0', w, pl+l, fl^ZERO_PAD);
		out(f, buf, s-buf);
		pad(f, '0', l-(ebuf-estr)-(s-buf), 0, 0);
		out(f, estr, ebuf-estr);
		pad(f, ' ', w, pl+l, fl^LEFT_ADJ);
		return MAX(w, pl+l);
	}
	if (p<0) p=6;

	if (y) y *= 0x1p28, e2-=28;

	if (e2<0) a=r=z=big;
	else a=r=z=big+sizeof(big)/sizeof(*big) - LDBL_MANT_DIG - 1;

	do {
		*z = y;
		y = 1000000000*(y-*z++);
	} while (y);

	while (e2>0) {
		uint32_t carry=0;
		int sh=MIN(29,e2);
		for (d=z-1; d>=a; d--) {
			uint64_t x = ((uint64_t)*d<<sh)+carry;
			*d = x % 1000000000;
			carry = x / 1000000000;
		}
		if (!z[-1] && z>a) z--;
		if (carry) *--a = carry;
		e2-=sh;
	}
	while (e2<0) {
		uint32_t carry=0, *b;
		int sh=MIN(9,-e2);
		for (d=a; d<z; d++) {
			uint32_t rm = *d & (1<<sh)-1;
			*d = (*d>>sh) + carry;
			carry = (1000000000>>sh) * rm;
		}
		if (!*a) a++;
		if (carry) *z++ = carry;
		/* Avoid (slow!) computation past requested precision */
		b = (t|32)=='f' ? r : a;
		if (z-b > 2+p/9) z = b+2+p/9;
		e2+=sh;
	}

	if (a<z) for (i=10, e=9*(r-a); *a>=i; i*=10, e++);
	else e=0;

	/* Perform rounding: j is precision after the radix (possibly neg) */
	j = p - ((t|32)!='f')*e - ((t|32)=='g' && p);
	if (j < 9*(z-r-1)) {
		uint32_t x;
		/* We avoid C's broken division of negative numbers */
		d = r + 1 + ((j+9*LDBL_MAX_EXP)/9 - LDBL_MAX_EXP);
		j += 9*LDBL_MAX_EXP;
		j %= 9;
		for (i=10, j++; j<9; i*=10, j++);
		x = *d % i;
		/* Are there any significant digits past j? */
		if (x || d+1!=z) {
			long double round = CONCAT(0x1p,LDBL_MANT_DIG);
			long double small;
			if (*d/i & 1) round += 2;
			if (x<i/2) small=0x0.8p0;
			else if (x==i/2 && d+1==z) small=0x1.0p0;
			else small=0x1.8p0;
			if (pl && *prefix=='-') round*=-1, small*=-1;
			*d -= x;
			/* Decide whether to round by probing round+small */
			if (round+small != round) {
				*d = *d + i;
				while (*d > 999999999) {
					*d--=0;
					(*d)++;
				}
				if (d<a) a=d;
				for (i=10, e=9*(r-a); *a>=i; i*=10, e++);
			}
		}
		if (z>d+1) z=d+1;
		for (; !z[-1] && z>a; z--);
	}
	
	if ((t|32)=='g') {
		if (!p) p++;
		if (p>e && e>=-4) {
			t--;
			p-=e+1;
		} else {
			t-=2;
			p--;
		}
		if (!(fl&ALT_FORM)) {
			/* Count trailing zeros in last place */
			if (z>a && z[-1]) for (i=10, j=0; z[-1]%i==0; i*=10, j++);
			else j=9;
			if ((t|32)=='f')
				p = MIN(p,MAX(0,9*(z-r-1)-j));
			else
				p = MIN(p,MAX(0,9*(z-r-1)+e-j));
		}
	}
	l = 1 + p + (p || (fl&ALT_FORM));
	if ((t|32)=='f') {
		if (e>0) l+=e;
	} else {
		estr=fmt_u(e<0 ? -e : e, ebuf);
		while(ebuf-estr<2) *--estr='0';
		*--estr = (e<0 ? '-' : '+');
		*--estr = t;
		l += ebuf-estr;
	}

	pad(f, ' ', w, pl+l, fl);
	out(f, prefix, pl);
	pad(f, '0', w, pl+l, fl^ZERO_PAD);

	if ((t|32)=='f') {
		if (a>r) a=r;
		for (d=a; d<=r; d++) {
			char *s = fmt_u(*d, buf+9);
			if (d!=a) while (s>buf) *--s='0';
			else if (s==buf+9) *--s='0';
			out(f, s, buf+9-s);
		}
		if (p || (fl&ALT_FORM)) out(f, ".", 1);
		for (; d<z && p>0; d++, p-=9) {
			char *s = fmt_u(*d, buf+9);
			while (s>buf) *--s='0';
			out(f, s, MIN(9,p));
		}
		pad(f, '0', p+9, 9, 0);
	} else {
		if (z<=a) z=a+1;
		for (d=a; d<z && p>=0; d++) {
			char *s = fmt_u(*d, buf+9);
			if (s==buf+9) *--s='0';
			if (d!=a) while (s>buf) *--s='0';
			else {
				out(f, s++, 1);
				if (p>0||(fl&ALT_FORM)) out(f, ".", 1);
			}
			out(f, s, MIN(buf+9-s, p));
			p -= buf+9-s;
		}
		pad(f, '0', p+18, 18, 0);
		out(f, estr, ebuf-estr);
	}

	pad(f, ' ', w, pl+l, fl^LEFT_ADJ);

	return MAX(w, pl+l);
}

static int getint(char **s) {
	int i;
	for (i=0; isdigit(**s); (*s)++)
		i = 10*i + (**s-'0');
	return i;
}

static int printf_core(FILE *f, const char *fmt, va_list *ap, union arg *nl_arg, int *nl_type)
{
	char *a, *z, *s=(char *)fmt;
	unsigned l10n=0, fl;
	int w, p;
	union arg arg;
	int argpos;
	unsigned st, ps;
	int cnt=0, l=0;
	int i;
	char buf[sizeof(uintmax_t)*3+3+LDBL_MANT_DIG/4];
	const char *prefix;
	int t, pl;
	wchar_t wc[2], *ws;
	char mb[4];

	for (;;) {
		/* Update output count, end loop when fmt is exhausted */
		if (cnt >= 0) {
			if (l > INT_MAX - cnt) {
				errno = EOVERFLOW;
				cnt = -1;
			} else cnt += l;
		}
		if (!*s) break;

		/* Handle literal text and %% format specifiers */
		for (a=s; *s && *s!='%'; s++);
		for (z=s; s[0]=='%' && s[1]=='%'; z++, s+=2);
		l = z-a;
		if (f) out(f, a, l);
		if (l) continue;

		if (isdigit(s[1]) && s[2]=='$') {
			l10n=1;
			argpos = s[1]-'0';
			s+=3;
		} else {
			argpos = -1;
			s++;
		}

		/* Read modifier flags */
		for (fl=0; (unsigned)*s-' '<32 && (FLAGMASK&(1U<<*s-' ')); s++)
			fl |= 1U<<*s-' ';

		/* Read field width */
		if (*s=='*') {
			if (isdigit(s[1]) && s[2]=='$') {
				l10n=1;
				nl_type[s[1]-'0'] = INT;
				w = nl_arg[s[1]-'0'].i;
				s+=3;
			} else if (!l10n) {
				w = f ? va_arg(*ap, int) : 0;
				s++;
			} else return -1;
			if (w<0) fl|=LEFT_ADJ, w=-w;
		} else if ((w=getint(&s))<0) return -1;

		/* Read precision */
		if (*s=='.' && s[1]=='*') {
			if (isdigit(s[2]) && s[3]=='$') {
				nl_type[s[2]-'0'] = INT;
				p = nl_arg[s[2]-'0'].i;
				s+=4;
			} else if (!l10n) {
				p = f ? va_arg(*ap, int) : 0;
				s+=2;
			} else return -1;
		} else if (*s=='.') {
			s++;
			p = getint(&s);
		} else p = -1;

		/* Format specifier state machine */
		st=0;
		do {
			if (OOB(*s)) return -1;
			ps=st;
			st=states[st]S(*s++);
		} while (st-1<STOP);
		if (!st) return -1;

		/* Check validity of argument type (nl/normal) */
		if (st==NOARG) {
			if (argpos>=0) return -1;
		} else {
			if (argpos>=0) nl_type[argpos]=st, arg=nl_arg[argpos];
			else if (f) pop_arg(&arg, st, ap);
			else return 0;
		}

		if (!f) continue;

		z = buf + sizeof(buf);
		prefix = "-+   0X0x";
		pl = 0;
		t = s[-1];

		/* Transform ls,lc -> S,C */
		if (ps && (t&15)==3) t&=~32;

		/* - and 0 flags are mutually exclusive */
		if (fl & LEFT_ADJ) fl &= ~ZERO_PAD;

		switch(t) {
		case 'n':
			switch(ps) {
			case BARE: *(int *)arg.p = cnt; break;
			case LPRE: *(long *)arg.p = cnt; break;
			case LLPRE: *(long long *)arg.p = cnt; break;
			case HPRE: *(unsigned short *)arg.p = cnt; break;
			case HHPRE: *(unsigned char *)arg.p = cnt; break;
			case ZTPRE: *(size_t *)arg.p = cnt; break;
			case JPRE: *(uintmax_t *)arg.p = cnt; break;
			}
			continue;
		case 'p':
			p = MAX(p, 2*sizeof(void*));
			t = 'x';
			fl |= ALT_FORM;
		case 'x': case 'X':
			a = fmt_x(arg.i, z, t&32);
			if (arg.i && (fl & ALT_FORM)) prefix+=(t>>4), pl=2;
			if (0) {
		case 'o':
			a = fmt_o(arg.i, z);
			if ((fl&ALT_FORM) && arg.i) prefix+=5, pl=1;
			} if (0) {
		case 'd': case 'i':
			pl=1;
			if (arg.i>INTMAX_MAX) {
				arg.i=-arg.i;
			} else if (fl & MARK_POS) {
				prefix++;
			} else if (fl & PAD_POS) {
				prefix+=2;
			} else pl=0;
		case 'u':
			a = fmt_u(arg.i, z);
			}
			if (p>=0) fl &= ~ZERO_PAD;
			if (!arg.i && !p) {
				a=z;
				break;
			}
			p = MAX(p, z-a + !arg.i);
			break;
		case 'c':
			*(a=z-(p=1))=arg.i;
			fl &= ~ZERO_PAD;
			break;
		case 'm':
			if (1) a = strerror(errno); else
		case 's':
			a = arg.p ? arg.p : "(null)";
			z = memchr(a, 0, p);
			if (!z) z=a+p;
			else p=z-a;
			fl &= ~ZERO_PAD;
			break;
		case 'C':
			wc[0] = arg.i;
			wc[1] = 0;
			arg.p = wc;
			p = -1;
		case 'S':
			ws = arg.p;
			for (i=l=0; i<0U+p && *ws && (l=wctomb(mb, *ws++))>=0 && l<=0U+p-i; i+=l);
			if (l<0) return -1;
			p = i;
			pad(f, ' ', w, p, fl);
			ws = arg.p;
			for (i=0; i<0U+p && *ws && i+(l=wctomb(mb, *ws++))<=p; i+=l)
				out(f, mb, l);
			pad(f, ' ', w, p, fl^LEFT_ADJ);
			l = w>p ? w : p;
			continue;
		case 'e': case 'f': case 'g': case 'a':
		case 'E': case 'F': case 'G': case 'A':
			l = fmt_fp(f, arg.f, w, p, fl, t);
			continue;
		}

		if (p < z-a) p = z-a;
		if (w < pl+p) w = pl+p;

		pad(f, ' ', w, pl+p, fl);
		out(f, prefix, pl);
		pad(f, '0', w, pl+p, fl^ZERO_PAD);
		pad(f, '0', p, z-a, 0);
		out(f, a, z-a);
		pad(f, ' ', w, pl+p, fl^LEFT_ADJ);

		l = w;
	}

	if (f) return cnt;
	if (!l10n) return 0;

	for (i=1; i<=NL_ARGMAX && nl_type[i]; i++)
		pop_arg(nl_arg+i, nl_type[i], ap);
	for (; i<=NL_ARGMAX && !nl_type[i]; i++);
	if (i<=NL_ARGMAX) return -1;
	return 1;
}

int vfprintf(FILE *restrict f, const char *restrict fmt, va_list ap)
{
	va_list ap2;
	int nl_type[NL_ARGMAX+1] = {0};
	union arg nl_arg[NL_ARGMAX+1];
	unsigned char internal_buf[80], *saved_buf = 0;
	int ret;

	/* the copy allows passing va_list* even if va_list is an array */
	va_copy(ap2, ap);
	if (printf_core(0, fmt, &ap2, nl_arg, nl_type) < 0) {
		va_end(ap2);
		return -1;
	}

	FLOCK(f);
	if (!f->buf_size) {
		saved_buf = f->buf;
		f->wpos = f->wbase = f->buf = internal_buf;
		f->buf_size = sizeof internal_buf;
		f->wend = internal_buf + sizeof internal_buf;
	}
	ret = printf_core(f, fmt, &ap2, nl_arg, nl_type);
	if (saved_buf) {
		f->write(f, 0, 0);
		if (!f->wpos) ret = -1;
		f->buf = saved_buf;
		f->buf_size = 0;
		f->wpos = f->wbase = f->wend = 0;
	}
	FUNLOCK(f);
	va_end(ap2);
	return ret;
}