xref: /openbmc/u-boot/lib/vsprintf.c (revision 32df39c7)
1 /*
2  *  linux/lib/vsprintf.c
3  *
4  *  Copyright (C) 1991, 1992  Linus Torvalds
5  */
6 
7 /* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
8 /*
9  * Wirzenius wrote this portably, Torvalds fucked it up :-)
10  *
11  * from hush: simple_itoa() was lifted from boa-0.93.15
12  */
13 
14 #include <stdarg.h>
15 #include <linux/types.h>
16 #include <linux/string.h>
17 #include <linux/ctype.h>
18 #include <errno.h>
19 
20 #include <common.h>
21 #if !defined(CONFIG_PANIC_HANG)
22 #include <command.h>
23 #endif
24 
25 #include <div64.h>
26 #define noinline __attribute__((noinline))
27 
28 unsigned long simple_strtoul(const char *cp, char **endp,
29 				unsigned int base)
30 {
31 	unsigned long result = 0;
32 	unsigned long value;
33 
34 	if (*cp == '0') {
35 		cp++;
36 		if ((*cp == 'x') && isxdigit(cp[1])) {
37 			base = 16;
38 			cp++;
39 		}
40 
41 		if (!base)
42 			base = 8;
43 	}
44 
45 	if (!base)
46 		base = 10;
47 
48 	while (isxdigit(*cp) && (value = isdigit(*cp) ? *cp-'0' : (islower(*cp)
49 	    ? toupper(*cp) : *cp)-'A'+10) < base) {
50 		result = result*base + value;
51 		cp++;
52 	}
53 
54 	if (endp)
55 		*endp = (char *)cp;
56 
57 	return result;
58 }
59 
60 int strict_strtoul(const char *cp, unsigned int base, unsigned long *res)
61 {
62 	char *tail;
63 	unsigned long val;
64 	size_t len;
65 
66 	*res = 0;
67 	len = strlen(cp);
68 	if (len == 0)
69 		return -EINVAL;
70 
71 	val = simple_strtoul(cp, &tail, base);
72 	if (tail == cp)
73 		return -EINVAL;
74 
75 	if ((*tail == '\0') ||
76 		((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) {
77 		*res = val;
78 		return 0;
79 	}
80 
81 	return -EINVAL;
82 }
83 
84 long simple_strtol(const char *cp, char **endp, unsigned int base)
85 {
86 	if (*cp == '-')
87 		return -simple_strtoul(cp + 1, endp, base);
88 
89 	return simple_strtoul(cp, endp, base);
90 }
91 
92 unsigned long ustrtoul(const char *cp, char **endp, unsigned int base)
93 {
94 	unsigned long result = simple_strtoul(cp, endp, base);
95 	switch (**endp) {
96 	case 'G':
97 		result *= 1024;
98 		/* fall through */
99 	case 'M':
100 		result *= 1024;
101 		/* fall through */
102 	case 'K':
103 	case 'k':
104 		result *= 1024;
105 		if ((*endp)[1] == 'i') {
106 			if ((*endp)[2] == 'B')
107 				(*endp) += 3;
108 			else
109 				(*endp) += 2;
110 		}
111 	}
112 	return result;
113 }
114 
115 unsigned long long ustrtoull(const char *cp, char **endp, unsigned int base)
116 {
117 	unsigned long long result = simple_strtoull(cp, endp, base);
118 	switch (**endp) {
119 	case 'G':
120 		result *= 1024;
121 		/* fall through */
122 	case 'M':
123 		result *= 1024;
124 		/* fall through */
125 	case 'K':
126 	case 'k':
127 		result *= 1024;
128 		if ((*endp)[1] == 'i') {
129 			if ((*endp)[2] == 'B')
130 				(*endp) += 3;
131 			else
132 				(*endp) += 2;
133 		}
134 	}
135 	return result;
136 }
137 
138 unsigned long long simple_strtoull(const char *cp, char **endp,
139 					unsigned int base)
140 {
141 	unsigned long long result = 0, value;
142 
143 	if (*cp == '0') {
144 		cp++;
145 		if ((*cp == 'x') && isxdigit(cp[1])) {
146 			base = 16;
147 			cp++;
148 		}
149 
150 		if (!base)
151 			base = 8;
152 	}
153 
154 	if (!base)
155 		base = 10;
156 
157 	while (isxdigit(*cp) && (value = isdigit(*cp) ? *cp - '0'
158 		: (islower(*cp) ? toupper(*cp) : *cp) - 'A' + 10) < base) {
159 		result = result * base + value;
160 		cp++;
161 	}
162 
163 	if (endp)
164 		*endp = (char *) cp;
165 
166 	return result;
167 }
168 
169 /* we use this so that we can do without the ctype library */
170 #define is_digit(c)	((c) >= '0' && (c) <= '9')
171 
172 static int skip_atoi(const char **s)
173 {
174 	int i = 0;
175 
176 	while (is_digit(**s))
177 		i = i * 10 + *((*s)++) - '0';
178 
179 	return i;
180 }
181 
182 /* Decimal conversion is by far the most typical, and is used
183  * for /proc and /sys data. This directly impacts e.g. top performance
184  * with many processes running. We optimize it for speed
185  * using code from
186  * http://www.cs.uiowa.edu/~jones/bcd/decimal.html
187  * (with permission from the author, Douglas W. Jones). */
188 
189 /* Formats correctly any integer in [0,99999].
190  * Outputs from one to five digits depending on input.
191  * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */
192 static char *put_dec_trunc(char *buf, unsigned q)
193 {
194 	unsigned d3, d2, d1, d0;
195 	d1 = (q>>4) & 0xf;
196 	d2 = (q>>8) & 0xf;
197 	d3 = (q>>12);
198 
199 	d0 = 6*(d3 + d2 + d1) + (q & 0xf);
200 	q = (d0 * 0xcd) >> 11;
201 	d0 = d0 - 10*q;
202 	*buf++ = d0 + '0'; /* least significant digit */
203 	d1 = q + 9*d3 + 5*d2 + d1;
204 	if (d1 != 0) {
205 		q = (d1 * 0xcd) >> 11;
206 		d1 = d1 - 10*q;
207 		*buf++ = d1 + '0'; /* next digit */
208 
209 		d2 = q + 2*d2;
210 		if ((d2 != 0) || (d3 != 0)) {
211 			q = (d2 * 0xd) >> 7;
212 			d2 = d2 - 10*q;
213 			*buf++ = d2 + '0'; /* next digit */
214 
215 			d3 = q + 4*d3;
216 			if (d3 != 0) {
217 				q = (d3 * 0xcd) >> 11;
218 				d3 = d3 - 10*q;
219 				*buf++ = d3 + '0';  /* next digit */
220 				if (q != 0)
221 					*buf++ = q + '0'; /* most sign. digit */
222 			}
223 		}
224 	}
225 	return buf;
226 }
227 /* Same with if's removed. Always emits five digits */
228 static char *put_dec_full(char *buf, unsigned q)
229 {
230 	/* BTW, if q is in [0,9999], 8-bit ints will be enough, */
231 	/* but anyway, gcc produces better code with full-sized ints */
232 	unsigned d3, d2, d1, d0;
233 	d1 = (q>>4) & 0xf;
234 	d2 = (q>>8) & 0xf;
235 	d3 = (q>>12);
236 
237 	/*
238 	 * Possible ways to approx. divide by 10
239 	 * gcc -O2 replaces multiply with shifts and adds
240 	 * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
241 	 * (x * 0x67) >> 10:  1100111
242 	 * (x * 0x34) >> 9:    110100 - same
243 	 * (x * 0x1a) >> 8:     11010 - same
244 	 * (x * 0x0d) >> 7:      1101 - same, shortest code (on i386)
245 	 */
246 
247 	d0 = 6*(d3 + d2 + d1) + (q & 0xf);
248 	q = (d0 * 0xcd) >> 11;
249 	d0 = d0 - 10*q;
250 	*buf++ = d0 + '0';
251 	d1 = q + 9*d3 + 5*d2 + d1;
252 		q = (d1 * 0xcd) >> 11;
253 		d1 = d1 - 10*q;
254 		*buf++ = d1 + '0';
255 
256 		d2 = q + 2*d2;
257 			q = (d2 * 0xd) >> 7;
258 			d2 = d2 - 10*q;
259 			*buf++ = d2 + '0';
260 
261 			d3 = q + 4*d3;
262 				q = (d3 * 0xcd) >> 11; /* - shorter code */
263 				/* q = (d3 * 0x67) >> 10; - would also work */
264 				d3 = d3 - 10*q;
265 				*buf++ = d3 + '0';
266 					*buf++ = q + '0';
267 	return buf;
268 }
269 /* No inlining helps gcc to use registers better */
270 static noinline char *put_dec(char *buf, uint64_t num)
271 {
272 	while (1) {
273 		unsigned rem;
274 		if (num < 100000)
275 			return put_dec_trunc(buf, num);
276 		rem = do_div(num, 100000);
277 		buf = put_dec_full(buf, rem);
278 	}
279 }
280 
281 #define ZEROPAD	1		/* pad with zero */
282 #define SIGN	2		/* unsigned/signed long */
283 #define PLUS	4		/* show plus */
284 #define SPACE	8		/* space if plus */
285 #define LEFT	16		/* left justified */
286 #define SMALL	32		/* Must be 32 == 0x20 */
287 #define SPECIAL	64		/* 0x */
288 
289 #ifdef CONFIG_SYS_VSNPRINTF
290 /*
291  * Macro to add a new character to our output string, but only if it will
292  * fit. The macro moves to the next character position in the output string.
293  */
294 #define ADDCH(str, ch) do { \
295 	if ((str) < end) \
296 		*(str) = (ch); \
297 	++str; \
298 	} while (0)
299 #else
300 #define ADDCH(str, ch)	(*(str)++ = (ch))
301 #endif
302 
303 static char *number(char *buf, char *end, u64 num,
304 		int base, int size, int precision, int type)
305 {
306 	/* we are called with base 8, 10 or 16, only, thus don't need "G..."  */
307 	static const char digits[16] = "0123456789ABCDEF";
308 
309 	char tmp[66];
310 	char sign;
311 	char locase;
312 	int need_pfx = ((type & SPECIAL) && base != 10);
313 	int i;
314 
315 	/* locase = 0 or 0x20. ORing digits or letters with 'locase'
316 	 * produces same digits or (maybe lowercased) letters */
317 	locase = (type & SMALL);
318 	if (type & LEFT)
319 		type &= ~ZEROPAD;
320 	sign = 0;
321 	if (type & SIGN) {
322 		if ((s64) num < 0) {
323 			sign = '-';
324 			num = -(s64) num;
325 			size--;
326 		} else if (type & PLUS) {
327 			sign = '+';
328 			size--;
329 		} else if (type & SPACE) {
330 			sign = ' ';
331 			size--;
332 		}
333 	}
334 	if (need_pfx) {
335 		size--;
336 		if (base == 16)
337 			size--;
338 	}
339 
340 	/* generate full string in tmp[], in reverse order */
341 	i = 0;
342 	if (num == 0)
343 		tmp[i++] = '0';
344 	/* Generic code, for any base:
345 	else do {
346 		tmp[i++] = (digits[do_div(num,base)] | locase);
347 	} while (num != 0);
348 	*/
349 	else if (base != 10) { /* 8 or 16 */
350 		int mask = base - 1;
351 		int shift = 3;
352 
353 		if (base == 16)
354 			shift = 4;
355 
356 		do {
357 			tmp[i++] = (digits[((unsigned char)num) & mask]
358 					| locase);
359 			num >>= shift;
360 		} while (num);
361 	} else { /* base 10 */
362 		i = put_dec(tmp, num) - tmp;
363 	}
364 
365 	/* printing 100 using %2d gives "100", not "00" */
366 	if (i > precision)
367 		precision = i;
368 	/* leading space padding */
369 	size -= precision;
370 	if (!(type & (ZEROPAD + LEFT))) {
371 		while (--size >= 0)
372 			ADDCH(buf, ' ');
373 	}
374 	/* sign */
375 	if (sign)
376 		ADDCH(buf, sign);
377 	/* "0x" / "0" prefix */
378 	if (need_pfx) {
379 		ADDCH(buf, '0');
380 		if (base == 16)
381 			ADDCH(buf, 'X' | locase);
382 	}
383 	/* zero or space padding */
384 	if (!(type & LEFT)) {
385 		char c = (type & ZEROPAD) ? '0' : ' ';
386 
387 		while (--size >= 0)
388 			ADDCH(buf, c);
389 	}
390 	/* hmm even more zero padding? */
391 	while (i <= --precision)
392 		ADDCH(buf, '0');
393 	/* actual digits of result */
394 	while (--i >= 0)
395 		ADDCH(buf, tmp[i]);
396 	/* trailing space padding */
397 	while (--size >= 0)
398 		ADDCH(buf, ' ');
399 	return buf;
400 }
401 
402 static char *string(char *buf, char *end, char *s, int field_width,
403 		int precision, int flags)
404 {
405 	int len, i;
406 
407 	if (s == NULL)
408 		s = "<NULL>";
409 
410 	len = strnlen(s, precision);
411 
412 	if (!(flags & LEFT))
413 		while (len < field_width--)
414 			ADDCH(buf, ' ');
415 	for (i = 0; i < len; ++i)
416 		ADDCH(buf, *s++);
417 	while (len < field_width--)
418 		ADDCH(buf, ' ');
419 	return buf;
420 }
421 
422 #ifdef CONFIG_CMD_NET
423 static const char hex_asc[] = "0123456789abcdef";
424 #define hex_asc_lo(x)	hex_asc[((x) & 0x0f)]
425 #define hex_asc_hi(x)	hex_asc[((x) & 0xf0) >> 4]
426 
427 static inline char *pack_hex_byte(char *buf, u8 byte)
428 {
429 	*buf++ = hex_asc_hi(byte);
430 	*buf++ = hex_asc_lo(byte);
431 	return buf;
432 }
433 
434 static char *mac_address_string(char *buf, char *end, u8 *addr, int field_width,
435 				int precision, int flags)
436 {
437 	/* (6 * 2 hex digits), 5 colons and trailing zero */
438 	char mac_addr[6 * 3];
439 	char *p = mac_addr;
440 	int i;
441 
442 	for (i = 0; i < 6; i++) {
443 		p = pack_hex_byte(p, addr[i]);
444 		if (!(flags & SPECIAL) && i != 5)
445 			*p++ = ':';
446 	}
447 	*p = '\0';
448 
449 	return string(buf, end, mac_addr, field_width, precision,
450 		      flags & ~SPECIAL);
451 }
452 
453 static char *ip6_addr_string(char *buf, char *end, u8 *addr, int field_width,
454 			 int precision, int flags)
455 {
456 	/* (8 * 4 hex digits), 7 colons and trailing zero */
457 	char ip6_addr[8 * 5];
458 	char *p = ip6_addr;
459 	int i;
460 
461 	for (i = 0; i < 8; i++) {
462 		p = pack_hex_byte(p, addr[2 * i]);
463 		p = pack_hex_byte(p, addr[2 * i + 1]);
464 		if (!(flags & SPECIAL) && i != 7)
465 			*p++ = ':';
466 	}
467 	*p = '\0';
468 
469 	return string(buf, end, ip6_addr, field_width, precision,
470 		      flags & ~SPECIAL);
471 }
472 
473 static char *ip4_addr_string(char *buf, char *end, u8 *addr, int field_width,
474 			 int precision, int flags)
475 {
476 	/* (4 * 3 decimal digits), 3 dots and trailing zero */
477 	char ip4_addr[4 * 4];
478 	char temp[3];	/* hold each IP quad in reverse order */
479 	char *p = ip4_addr;
480 	int i, digits;
481 
482 	for (i = 0; i < 4; i++) {
483 		digits = put_dec_trunc(temp, addr[i]) - temp;
484 		/* reverse the digits in the quad */
485 		while (digits--)
486 			*p++ = temp[digits];
487 		if (i != 3)
488 			*p++ = '.';
489 	}
490 	*p = '\0';
491 
492 	return string(buf, end, ip4_addr, field_width, precision,
493 		      flags & ~SPECIAL);
494 }
495 #endif
496 
497 /*
498  * Show a '%p' thing.  A kernel extension is that the '%p' is followed
499  * by an extra set of alphanumeric characters that are extended format
500  * specifiers.
501  *
502  * Right now we handle:
503  *
504  * - 'M' For a 6-byte MAC address, it prints the address in the
505  *       usual colon-separated hex notation
506  * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way (dot-separated
507  *       decimal for v4 and colon separated network-order 16 bit hex for v6)
508  * - 'i' [46] for 'raw' IPv4/IPv6 addresses, IPv6 omits the colons, IPv4 is
509  *       currently the same
510  *
511  * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
512  * function pointers are really function descriptors, which contain a
513  * pointer to the real address.
514  */
515 static char *pointer(const char *fmt, char *buf, char *end, void *ptr,
516 		int field_width, int precision, int flags)
517 {
518 	u64 num = (uintptr_t)ptr;
519 
520 	/*
521 	 * Being a boot loader, we explicitly allow pointers to
522 	 * (physical) address null.
523 	 */
524 #if 0
525 	if (!ptr)
526 		return string(buf, end, "(null)", field_width, precision,
527 			      flags);
528 #endif
529 
530 #ifdef CONFIG_CMD_NET
531 	switch (*fmt) {
532 	case 'a':
533 		flags |= SPECIAL | ZEROPAD;
534 
535 		switch (fmt[1]) {
536 		case 'p':
537 		default:
538 			field_width = sizeof(phys_addr_t) * 2 + 2;
539 			num = *(phys_addr_t *)ptr;
540 			break;
541 		}
542 		break;
543 	case 'm':
544 		flags |= SPECIAL;
545 		/* Fallthrough */
546 	case 'M':
547 		return mac_address_string(buf, end, ptr, field_width,
548 					  precision, flags);
549 	case 'i':
550 		flags |= SPECIAL;
551 		/* Fallthrough */
552 	case 'I':
553 		if (fmt[1] == '6')
554 			return ip6_addr_string(buf, end, ptr, field_width,
555 					       precision, flags);
556 		if (fmt[1] == '4')
557 			return ip4_addr_string(buf, end, ptr, field_width,
558 					       precision, flags);
559 		flags &= ~SPECIAL;
560 		break;
561 	}
562 #endif
563 	flags |= SMALL;
564 	if (field_width == -1) {
565 		field_width = 2*sizeof(void *);
566 		flags |= ZEROPAD;
567 	}
568 	return number(buf, end, num, 16, field_width, precision, flags);
569 }
570 
571 static int vsnprintf_internal(char *buf, size_t size, const char *fmt,
572 			      va_list args)
573 {
574 	u64 num;
575 	int base;
576 	char *str;
577 
578 	int flags;		/* flags to number() */
579 
580 	int field_width;	/* width of output field */
581 	int precision;		/* min. # of digits for integers; max
582 				   number of chars for from string */
583 	int qualifier;		/* 'h', 'l', or 'L' for integer fields */
584 				/* 'z' support added 23/7/1999 S.H.    */
585 				/* 'z' changed to 'Z' --davidm 1/25/99 */
586 				/* 't' added for ptrdiff_t */
587 	char *end = buf + size;
588 
589 #ifdef CONFIG_SYS_VSNPRINTF
590 	/* Make sure end is always >= buf - do we want this in U-Boot? */
591 	if (end < buf) {
592 		end = ((void *)-1);
593 		size = end - buf;
594 	}
595 #endif
596 	str = buf;
597 
598 	for (; *fmt ; ++fmt) {
599 		if (*fmt != '%') {
600 			ADDCH(str, *fmt);
601 			continue;
602 		}
603 
604 		/* process flags */
605 		flags = 0;
606 repeat:
607 			++fmt;		/* this also skips first '%' */
608 			switch (*fmt) {
609 			case '-':
610 				flags |= LEFT;
611 				goto repeat;
612 			case '+':
613 				flags |= PLUS;
614 				goto repeat;
615 			case ' ':
616 				flags |= SPACE;
617 				goto repeat;
618 			case '#':
619 				flags |= SPECIAL;
620 				goto repeat;
621 			case '0':
622 				flags |= ZEROPAD;
623 				goto repeat;
624 			}
625 
626 		/* get field width */
627 		field_width = -1;
628 		if (is_digit(*fmt))
629 			field_width = skip_atoi(&fmt);
630 		else if (*fmt == '*') {
631 			++fmt;
632 			/* it's the next argument */
633 			field_width = va_arg(args, int);
634 			if (field_width < 0) {
635 				field_width = -field_width;
636 				flags |= LEFT;
637 			}
638 		}
639 
640 		/* get the precision */
641 		precision = -1;
642 		if (*fmt == '.') {
643 			++fmt;
644 			if (is_digit(*fmt))
645 				precision = skip_atoi(&fmt);
646 			else if (*fmt == '*') {
647 				++fmt;
648 				/* it's the next argument */
649 				precision = va_arg(args, int);
650 			}
651 			if (precision < 0)
652 				precision = 0;
653 		}
654 
655 		/* get the conversion qualifier */
656 		qualifier = -1;
657 		if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
658 		    *fmt == 'Z' || *fmt == 'z' || *fmt == 't') {
659 			qualifier = *fmt;
660 			++fmt;
661 			if (qualifier == 'l' && *fmt == 'l') {
662 				qualifier = 'L';
663 				++fmt;
664 			}
665 		}
666 
667 		/* default base */
668 		base = 10;
669 
670 		switch (*fmt) {
671 		case 'c':
672 			if (!(flags & LEFT)) {
673 				while (--field_width > 0)
674 					ADDCH(str, ' ');
675 			}
676 			ADDCH(str, (unsigned char) va_arg(args, int));
677 			while (--field_width > 0)
678 				ADDCH(str, ' ');
679 			continue;
680 
681 		case 's':
682 			str = string(str, end, va_arg(args, char *),
683 				     field_width, precision, flags);
684 			continue;
685 
686 		case 'p':
687 			str = pointer(fmt + 1, str, end,
688 					va_arg(args, void *),
689 					field_width, precision, flags);
690 			/* Skip all alphanumeric pointer suffixes */
691 			while (isalnum(fmt[1]))
692 				fmt++;
693 			continue;
694 
695 		case 'n':
696 			if (qualifier == 'l') {
697 				long *ip = va_arg(args, long *);
698 				*ip = (str - buf);
699 			} else {
700 				int *ip = va_arg(args, int *);
701 				*ip = (str - buf);
702 			}
703 			continue;
704 
705 		case '%':
706 			ADDCH(str, '%');
707 			continue;
708 
709 		/* integer number formats - set up the flags and "break" */
710 		case 'o':
711 			base = 8;
712 			break;
713 
714 		case 'x':
715 			flags |= SMALL;
716 		case 'X':
717 			base = 16;
718 			break;
719 
720 		case 'd':
721 		case 'i':
722 			flags |= SIGN;
723 		case 'u':
724 			break;
725 
726 		default:
727 			ADDCH(str, '%');
728 			if (*fmt)
729 				ADDCH(str, *fmt);
730 			else
731 				--fmt;
732 			continue;
733 		}
734 		if (qualifier == 'L')  /* "quad" for 64 bit variables */
735 			num = va_arg(args, unsigned long long);
736 		else if (qualifier == 'l') {
737 			num = va_arg(args, unsigned long);
738 			if (flags & SIGN)
739 				num = (signed long) num;
740 		} else if (qualifier == 'Z' || qualifier == 'z') {
741 			num = va_arg(args, size_t);
742 		} else if (qualifier == 't') {
743 			num = va_arg(args, ptrdiff_t);
744 		} else if (qualifier == 'h') {
745 			num = (unsigned short) va_arg(args, int);
746 			if (flags & SIGN)
747 				num = (signed short) num;
748 		} else {
749 			num = va_arg(args, unsigned int);
750 			if (flags & SIGN)
751 				num = (signed int) num;
752 		}
753 		str = number(str, end, num, base, field_width, precision,
754 			     flags);
755 	}
756 
757 #ifdef CONFIG_SYS_VSNPRINTF
758 	if (size > 0) {
759 		ADDCH(str, '\0');
760 		if (str > end)
761 			end[-1] = '\0';
762 		--str;
763 	}
764 #else
765 	*str = '\0';
766 #endif
767 	/* the trailing null byte doesn't count towards the total */
768 	return str - buf;
769 }
770 
771 #ifdef CONFIG_SYS_VSNPRINTF
772 int vsnprintf(char *buf, size_t size, const char *fmt,
773 			      va_list args)
774 {
775 	return vsnprintf_internal(buf, size, fmt, args);
776 }
777 
778 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
779 {
780 	int i;
781 
782 	i = vsnprintf(buf, size, fmt, args);
783 
784 	if (likely(i < size))
785 		return i;
786 	if (size != 0)
787 		return size - 1;
788 	return 0;
789 }
790 
791 int snprintf(char *buf, size_t size, const char *fmt, ...)
792 {
793 	va_list args;
794 	int i;
795 
796 	va_start(args, fmt);
797 	i = vsnprintf(buf, size, fmt, args);
798 	va_end(args);
799 
800 	return i;
801 }
802 
803 int scnprintf(char *buf, size_t size, const char *fmt, ...)
804 {
805 	va_list args;
806 	int i;
807 
808 	va_start(args, fmt);
809 	i = vscnprintf(buf, size, fmt, args);
810 	va_end(args);
811 
812 	return i;
813 }
814 #endif /* CONFIG_SYS_VSNPRINT */
815 
816 /**
817  * Format a string and place it in a buffer (va_list version)
818  *
819  * @param buf	The buffer to place the result into
820  * @param fmt	The format string to use
821  * @param args	Arguments for the format string
822  *
823  * The function returns the number of characters written
824  * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
825  * buffer overflows.
826  *
827  * If you're not already dealing with a va_list consider using sprintf().
828  */
829 int vsprintf(char *buf, const char *fmt, va_list args)
830 {
831 	return vsnprintf_internal(buf, INT_MAX, fmt, args);
832 }
833 
834 int sprintf(char *buf, const char *fmt, ...)
835 {
836 	va_list args;
837 	int i;
838 
839 	va_start(args, fmt);
840 	i = vsprintf(buf, fmt, args);
841 	va_end(args);
842 	return i;
843 }
844 
845 void panic(const char *fmt, ...)
846 {
847 	va_list args;
848 	va_start(args, fmt);
849 	vprintf(fmt, args);
850 	putc('\n');
851 	va_end(args);
852 #if defined(CONFIG_PANIC_HANG)
853 	hang();
854 #else
855 	udelay(100000);	/* allow messages to go out */
856 	do_reset(NULL, 0, 0, NULL);
857 #endif
858 	while (1)
859 		;
860 }
861 
862 void __assert_fail(const char *assertion, const char *file, unsigned line,
863 		   const char *function)
864 {
865 	/* This will not return */
866 	panic("%s:%u: %s: Assertion `%s' failed.", file, line, function,
867 	      assertion);
868 }
869 
870 char *simple_itoa(ulong i)
871 {
872 	/* 21 digits plus null terminator, good for 64-bit or smaller ints */
873 	static char local[22];
874 	char *p = &local[21];
875 
876 	*p-- = '\0';
877 	do {
878 		*p-- = '0' + i % 10;
879 		i /= 10;
880 	} while (i > 0);
881 	return p + 1;
882 }
883 
884 /* We don't seem to have %'d in U-Boot */
885 void print_grouped_ull(unsigned long long int_val, int digits)
886 {
887 	char str[21], *s;
888 	int grab = 3;
889 
890 	digits = (digits + 2) / 3;
891 	sprintf(str, "%*llu", digits * 3, int_val);
892 	for (s = str; *s; s += grab) {
893 		if (s != str)
894 			putc(s[-1] != ' ' ? ',' : ' ');
895 		printf("%.*s", grab, s);
896 		grab = 3;
897 	}
898 }
899