projects/linux·blob v2.6.18-rc1 · refs

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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
12/*
13 * Fri Jul 13 2001 Crutcher Dunnavant <[email protected]>
14 * - changed to provide snprintf and vsnprintf functions
15 * So Feb 1 16:51:32 CET 2004 Juergen Quade <[email protected]>
16 * - scnprintf and vscnprintf
17 */
18
19#include <stdarg.h>
20#include <linux/module.h>
21#include <linux/types.h>
22#include <linux/string.h>
23#include <linux/ctype.h>
24#include <linux/kernel.h>
25
26#include <asm/page.h> /* for PAGE_SIZE */
27#include <asm/div64.h>
28
29/**
30 * simple_strtoul - convert a string to an unsigned long
31 * @cp: The start of the string
32 * @endp: A pointer to the end of the parsed string will be placed here
33 * @base: The number base to use
34 */
35unsigned long simple_strtoul(const char *cp,char **endp,unsigned int base)
36{
37 unsigned long result = 0,value;
38
39 if (!base) {
40 base = 10;
41 if (*cp == '0') {
42 base = 8;
43 cp++;
44 if ((toupper(*cp) == 'X') && isxdigit(cp[1])) {
45 cp++;
46 base = 16;
47 }
48 }
49 } else if (base == 16) {
50 if (cp[0] == '0' && toupper(cp[1]) == 'X')
51 cp += 2;
52 }
53 while (isxdigit(*cp) &&
54 (value = isdigit(*cp) ? *cp-'0' : toupper(*cp)-'A'+10) < base) {
55 result = result*base + value;
56 cp++;
57 }
58 if (endp)
59 *endp = (char *)cp;
60 return result;
61}
62
63EXPORT_SYMBOL(simple_strtoul);
64
65/**
66 * simple_strtol - convert a string to a signed long
67 * @cp: The start of the string
68 * @endp: A pointer to the end of the parsed string will be placed here
69 * @base: The number base to use
70 */
71long simple_strtol(const char *cp,char **endp,unsigned int base)
72{
73 if(*cp=='-')
74 return -simple_strtoul(cp+1,endp,base);
75 return simple_strtoul(cp,endp,base);
76}
77
78EXPORT_SYMBOL(simple_strtol);
79
80/**
81 * simple_strtoull - convert a string to an unsigned long long
82 * @cp: The start of the string
83 * @endp: A pointer to the end of the parsed string will be placed here
84 * @base: The number base to use
85 */
86unsigned long long simple_strtoull(const char *cp,char **endp,unsigned int base)
87{
88 unsigned long long result = 0,value;
89
90 if (!base) {
91 base = 10;
92 if (*cp == '0') {
93 base = 8;
94 cp++;
95 if ((toupper(*cp) == 'X') && isxdigit(cp[1])) {
96 cp++;
97 base = 16;
98 }
99 }
100 } else if (base == 16) {
101 if (cp[0] == '0' && toupper(cp[1]) == 'X')
102 cp += 2;
103 }
104 while (isxdigit(*cp) && (value = isdigit(*cp) ? *cp-'0' : (islower(*cp)
105 ? toupper(*cp) : *cp)-'A'+10) < base) {
106 result = result*base + value;
107 cp++;
108 }
109 if (endp)
110 *endp = (char *)cp;
111 return result;
112}
113
114EXPORT_SYMBOL(simple_strtoull);
115
116/**
117 * simple_strtoll - convert a string to a signed long long
118 * @cp: The start of the string
119 * @endp: A pointer to the end of the parsed string will be placed here
120 * @base: The number base to use
121 */
122long long simple_strtoll(const char *cp,char **endp,unsigned int base)
123{
124 if(*cp=='-')
125 return -simple_strtoull(cp+1,endp,base);
126 return simple_strtoull(cp,endp,base);
127}
128
129static int skip_atoi(const char **s)
130{
131 int i=0;
132
133 while (isdigit(**s))
134 i = i*10 + *((*s)++) - '0';
135 return i;
136}
137
138#define ZEROPAD 1 /* pad with zero */
139#define SIGN 2 /* unsigned/signed long */
140#define PLUS 4 /* show plus */
141#define SPACE 8 /* space if plus */
142#define LEFT 16 /* left justified */
143#define SPECIAL 32 /* 0x */
144#define LARGE 64 /* use 'ABCDEF' instead of 'abcdef' */
145
146static char * number(char * buf, char * end, unsigned long long num, int base, int size, int precision, int type)
147{
148 char c,sign,tmp[66];
149 const char *digits;
150 static const char small_digits[] = "0123456789abcdefghijklmnopqrstuvwxyz";
151 static const char large_digits[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
152 int i;
153
154 digits = (type & LARGE) ? large_digits : small_digits;
155 if (type & LEFT)
156 type &= ~ZEROPAD;
157 if (base < 2 || base > 36)
158 return NULL;
159 c = (type & ZEROPAD) ? '0' : ' ';
160 sign = 0;
161 if (type & SIGN) {
162 if ((signed long long) num < 0) {
163 sign = '-';
164 num = - (signed long long) num;
165 size--;
166 } else if (type & PLUS) {
167 sign = '+';
168 size--;
169 } else if (type & SPACE) {
170 sign = ' ';
171 size--;
172 }
173 }
174 if (type & SPECIAL) {
175 if (base == 16)
176 size -= 2;
177 else if (base == 8)
178 size--;
179 }
180 i = 0;
181 if (num == 0)
182 tmp[i++]='0';
183 else while (num != 0)
184 tmp[i++] = digits[do_div(num,base)];
185 if (i > precision)
186 precision = i;
187 size -= precision;
188 if (!(type&(ZEROPAD+LEFT))) {
189 while(size-->0) {
190 if (buf < end)
191 *buf = ' ';
192 ++buf;
193 }
194 }
195 if (sign) {
196 if (buf < end)
197 *buf = sign;
198 ++buf;
199 }
200 if (type & SPECIAL) {
201 if (base==8) {
202 if (buf < end)
203 *buf = '0';
204 ++buf;
205 } else if (base==16) {
206 if (buf < end)
207 *buf = '0';
208 ++buf;
209 if (buf < end)
210 *buf = digits[33];
211 ++buf;
212 }
213 }
214 if (!(type & LEFT)) {
215 while (size-- > 0) {
216 if (buf < end)
217 *buf = c;
218 ++buf;
219 }
220 }
221 while (i < precision--) {
222 if (buf < end)
223 *buf = '0';
224 ++buf;
225 }
226 while (i-- > 0) {
227 if (buf < end)
228 *buf = tmp[i];
229 ++buf;
230 }
231 while (size-- > 0) {
232 if (buf < end)
233 *buf = ' ';
234 ++buf;
235 }
236 return buf;
237}
238
239/**
240 * vsnprintf - Format a string and place it in a buffer
241 * @buf: The buffer to place the result into
242 * @size: The size of the buffer, including the trailing null space
243 * @fmt: The format string to use
244 * @args: Arguments for the format string
245 *
246 * The return value is the number of characters which would
247 * be generated for the given input, excluding the trailing
248 * '\0', as per ISO C99. If you want to have the exact
249 * number of characters written into @buf as return value
250 * (not including the trailing '\0'), use vscnprintf. If the
251 * return is greater than or equal to @size, the resulting
252 * string is truncated.
253 *
254 * Call this function if you are already dealing with a va_list.
255 * You probably want snprintf instead.
256 */
257int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
258{
259 int len;
260 unsigned long long num;
261 int i, base;
262 char *str, *end, c;
263 const char *s;
264
265 int flags; /* flags to number() */
266
267 int field_width; /* width of output field */
268 int precision; /* min. # of digits for integers; max
269 number of chars for from string */
270 int qualifier; /* 'h', 'l', or 'L' for integer fields */
271 /* 'z' support added 23/7/1999 S.H. */
272 /* 'z' changed to 'Z' --davidm 1/25/99 */
273 /* 't' added for ptrdiff_t */
274
275 /* Reject out-of-range values early. Large positive sizes are
276 used for unknown buffer sizes. */
277 if (unlikely((int) size < 0)) {
278 /* There can be only one.. */
279 static int warn = 1;
280 WARN_ON(warn);
281 warn = 0;
282 return 0;
283 }
284
285 str = buf;
286 end = buf + size;
287
288 /* Make sure end is always >= buf */
289 if (end < buf) {
290 end = ((void *)-1);
291 size = end - buf;
292 }
293
294 for (; *fmt ; ++fmt) {
295 if (*fmt != '%') {
296 if (str < end)
297 *str = *fmt;
298 ++str;
299 continue;
300 }
301
302 /* process flags */
303 flags = 0;
304 repeat:
305 ++fmt; /* this also skips first '%' */
306 switch (*fmt) {
307 case '-': flags |= LEFT; goto repeat;
308 case '+': flags |= PLUS; goto repeat;
309 case ' ': flags |= SPACE; goto repeat;
310 case '#': flags |= SPECIAL; goto repeat;
311 case '0': flags |= ZEROPAD; goto repeat;
312 }
313
314 /* get field width */
315 field_width = -1;
316 if (isdigit(*fmt))
317 field_width = skip_atoi(&fmt);
318 else if (*fmt == '*') {
319 ++fmt;
320 /* it's the next argument */
321 field_width = va_arg(args, int);
322 if (field_width < 0) {
323 field_width = -field_width;
324 flags |= LEFT;
325 }
326 }
327
328 /* get the precision */
329 precision = -1;
330 if (*fmt == '.') {
331 ++fmt;
332 if (isdigit(*fmt))
333 precision = skip_atoi(&fmt);
334 else if (*fmt == '*') {
335 ++fmt;
336 /* it's the next argument */
337 precision = va_arg(args, int);
338 }
339 if (precision < 0)
340 precision = 0;
341 }
342
343 /* get the conversion qualifier */
344 qualifier = -1;
345 if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
346 *fmt =='Z' || *fmt == 'z' || *fmt == 't') {
347 qualifier = *fmt;
348 ++fmt;
349 if (qualifier == 'l' && *fmt == 'l') {
350 qualifier = 'L';
351 ++fmt;
352 }
353 }
354
355 /* default base */
356 base = 10;
357
358 switch (*fmt) {
359 case 'c':
360 if (!(flags & LEFT)) {
361 while (--field_width > 0) {
362 if (str < end)
363 *str = ' ';
364 ++str;
365 }
366 }
367 c = (unsigned char) va_arg(args, int);
368 if (str < end)
369 *str = c;
370 ++str;
371 while (--field_width > 0) {
372 if (str < end)
373 *str = ' ';
374 ++str;
375 }
376 continue;
377
378 case 's':
379 s = va_arg(args, char *);
380 if ((unsigned long)s < PAGE_SIZE)
381 s = "<NULL>";
382
383 len = strnlen(s, precision);
384
385 if (!(flags & LEFT)) {
386 while (len < field_width--) {
387 if (str < end)
388 *str = ' ';
389 ++str;
390 }
391 }
392 for (i = 0; i < len; ++i) {
393 if (str < end)
394 *str = *s;
395 ++str; ++s;
396 }
397 while (len < field_width--) {
398 if (str < end)
399 *str = ' ';
400 ++str;
401 }
402 continue;
403
404 case 'p':
405 if (field_width == -1) {
406 field_width = 2*sizeof(void *);
407 flags |= ZEROPAD;
408 }
409 str = number(str, end,
410 (unsigned long) va_arg(args, void *),
411 16, field_width, precision, flags);
412 continue;
413
414
415 case 'n':
416 /* FIXME:
417 * What does C99 say about the overflow case here? */
418 if (qualifier == 'l') {
419 long * ip = va_arg(args, long *);
420 *ip = (str - buf);
421 } else if (qualifier == 'Z' || qualifier == 'z') {
422 size_t * ip = va_arg(args, size_t *);
423 *ip = (str - buf);
424 } else {
425 int * ip = va_arg(args, int *);
426 *ip = (str - buf);
427 }
428 continue;
429
430 case '%':
431 if (str < end)
432 *str = '%';
433 ++str;
434 continue;
435
436 /* integer number formats - set up the flags and "break" */
437 case 'o':
438 base = 8;
439 break;
440
441 case 'X':
442 flags |= LARGE;
443 case 'x':
444 base = 16;
445 break;
446
447 case 'd':
448 case 'i':
449 flags |= SIGN;
450 case 'u':
451 break;
452
453 default:
454 if (str < end)
455 *str = '%';
456 ++str;
457 if (*fmt) {
458 if (str < end)
459 *str = *fmt;
460 ++str;
461 } else {
462 --fmt;
463 }
464 continue;
465 }
466 if (qualifier == 'L')
467 num = va_arg(args, long long);
468 else if (qualifier == 'l') {
469 num = va_arg(args, unsigned long);
470 if (flags & SIGN)
471 num = (signed long) num;
472 } else if (qualifier == 'Z' || qualifier == 'z') {
473 num = va_arg(args, size_t);
474 } else if (qualifier == 't') {
475 num = va_arg(args, ptrdiff_t);
476 } else if (qualifier == 'h') {
477 num = (unsigned short) va_arg(args, int);
478 if (flags & SIGN)
479 num = (signed short) num;
480 } else {
481 num = va_arg(args, unsigned int);
482 if (flags & SIGN)
483 num = (signed int) num;
484 }
485 str = number(str, end, num, base,
486 field_width, precision, flags);
487 }
488 if (size > 0) {
489 if (str < end)
490 *str = '\0';
491 else
492 end[-1] = '\0';
493 }
494 /* the trailing null byte doesn't count towards the total */
495 return str-buf;
496}
497
498EXPORT_SYMBOL(vsnprintf);
499
500/**
501 * vscnprintf - Format a string and place it in a buffer
502 * @buf: The buffer to place the result into
503 * @size: The size of the buffer, including the trailing null space
504 * @fmt: The format string to use
505 * @args: Arguments for the format string
506 *
507 * The return value is the number of characters which have been written into
508 * the @buf not including the trailing '\0'. If @size is <= 0 the function
509 * returns 0.
510 *
511 * Call this function if you are already dealing with a va_list.
512 * You probably want scnprintf instead.
513 */
514int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
515{
516 int i;
517
518 i=vsnprintf(buf,size,fmt,args);
519 return (i >= size) ? (size - 1) : i;
520}
521
522EXPORT_SYMBOL(vscnprintf);
523
524/**
525 * snprintf - Format a string and place it in a buffer
526 * @buf: The buffer to place the result into
527 * @size: The size of the buffer, including the trailing null space
528 * @fmt: The format string to use
529 * @...: Arguments for the format string
530 *
531 * The return value is the number of characters which would be
532 * generated for the given input, excluding the trailing null,
533 * as per ISO C99. If the return is greater than or equal to
534 * @size, the resulting string is truncated.
535 */
536int snprintf(char * buf, size_t size, const char *fmt, ...)
537{
538 va_list args;
539 int i;
540
541 va_start(args, fmt);
542 i=vsnprintf(buf,size,fmt,args);
543 va_end(args);
544 return i;
545}
546
547EXPORT_SYMBOL(snprintf);
548
549/**
550 * scnprintf - Format a string and place it in a buffer
551 * @buf: The buffer to place the result into
552 * @size: The size of the buffer, including the trailing null space
553 * @fmt: The format string to use
554 * @...: Arguments for the format string
555 *
556 * The return value is the number of characters written into @buf not including
557 * the trailing '\0'. If @size is <= 0 the function returns 0. If the return is
558 * greater than or equal to @size, the resulting string is truncated.
559 */
560
561int scnprintf(char * buf, size_t size, const char *fmt, ...)
562{
563 va_list args;
564 int i;
565
566 va_start(args, fmt);
567 i = vsnprintf(buf, size, fmt, args);
568 va_end(args);
569 return (i >= size) ? (size - 1) : i;
570}
571EXPORT_SYMBOL(scnprintf);
572
573/**
574 * vsprintf - Format a string and place it in a buffer
575 * @buf: The buffer to place the result into
576 * @fmt: The format string to use
577 * @args: Arguments for the format string
578 *
579 * The function returns the number of characters written
580 * into @buf. Use vsnprintf or vscnprintf in order to avoid
581 * buffer overflows.
582 *
583 * Call this function if you are already dealing with a va_list.
584 * You probably want sprintf instead.
585 */
586int vsprintf(char *buf, const char *fmt, va_list args)
587{
588 return vsnprintf(buf, INT_MAX, fmt, args);
589}
590
591EXPORT_SYMBOL(vsprintf);
592
593/**
594 * sprintf - Format a string and place it in a buffer
595 * @buf: The buffer to place the result into
596 * @fmt: The format string to use
597 * @...: Arguments for the format string
598 *
599 * The function returns the number of characters written
600 * into @buf. Use snprintf or scnprintf in order to avoid
601 * buffer overflows.
602 */
603int sprintf(char * buf, const char *fmt, ...)
604{
605 va_list args;
606 int i;
607
608 va_start(args, fmt);
609 i=vsnprintf(buf, INT_MAX, fmt, args);
610 va_end(args);
611 return i;
612}
613
614EXPORT_SYMBOL(sprintf);
615
616/**
617 * vsscanf - Unformat a buffer into a list of arguments
618 * @buf: input buffer
619 * @fmt: format of buffer
620 * @args: arguments
621 */
622int vsscanf(const char * buf, const char * fmt, va_list args)
623{
624 const char *str = buf;
625 char *next;
626 char digit;
627 int num = 0;
628 int qualifier;
629 int base;
630 int field_width;
631 int is_sign = 0;
632
633 while(*fmt && *str) {
634 /* skip any white space in format */
635 /* white space in format matchs any amount of
636 * white space, including none, in the input.
637 */
638 if (isspace(*fmt)) {
639 while (isspace(*fmt))
640 ++fmt;
641 while (isspace(*str))
642 ++str;
643 }
644
645 /* anything that is not a conversion must match exactly */
646 if (*fmt != '%' && *fmt) {
647 if (*fmt++ != *str++)
648 break;
649 continue;
650 }
651
652 if (!*fmt)
653 break;
654 ++fmt;
655
656 /* skip this conversion.
657 * advance both strings to next white space
658 */
659 if (*fmt == '*') {
660 while (!isspace(*fmt) && *fmt)
661 fmt++;
662 while (!isspace(*str) && *str)
663 str++;
664 continue;
665 }
666
667 /* get field width */
668 field_width = -1;
669 if (isdigit(*fmt))
670 field_width = skip_atoi(&fmt);
671
672 /* get conversion qualifier */
673 qualifier = -1;
674 if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
675 *fmt == 'Z' || *fmt == 'z') {
676 qualifier = *fmt++;
677 if (unlikely(qualifier == *fmt)) {
678 if (qualifier == 'h') {
679 qualifier = 'H';
680 fmt++;
681 } else if (qualifier == 'l') {
682 qualifier = 'L';
683 fmt++;
684 }
685 }
686 }
687 base = 10;
688 is_sign = 0;
689
690 if (!*fmt || !*str)
691 break;
692
693 switch(*fmt++) {
694 case 'c':
695 {
696 char *s = (char *) va_arg(args,char*);
697 if (field_width == -1)
698 field_width = 1;
699 do {
700 *s++ = *str++;
701 } while (--field_width > 0 && *str);
702 num++;
703 }
704 continue;
705 case 's':
706 {
707 char *s = (char *) va_arg(args, char *);
708 if(field_width == -1)
709 field_width = INT_MAX;
710 /* first, skip leading white space in buffer */
711 while (isspace(*str))
712 str++;
713
714 /* now copy until next white space */
715 while (*str && !isspace(*str) && field_width--) {
716 *s++ = *str++;
717 }
718 *s = '\0';
719 num++;
720 }
721 continue;
722 case 'n':
723 /* return number of characters read so far */
724 {
725 int *i = (int *)va_arg(args,int*);
726 *i = str - buf;
727 }
728 continue;
729 case 'o':
730 base = 8;
731 break;
732 case 'x':
733 case 'X':
734 base = 16;
735 break;
736 case 'i':
737 base = 0;
738 case 'd':
739 is_sign = 1;
740 case 'u':
741 break;
742 case '%':
743 /* looking for '%' in str */
744 if (*str++ != '%')
745 return num;
746 continue;
747 default:
748 /* invalid format; stop here */
749 return num;
750 }
751
752 /* have some sort of integer conversion.
753 * first, skip white space in buffer.
754 */
755 while (isspace(*str))
756 str++;
757
758 digit = *str;
759 if (is_sign && digit == '-')
760 digit = *(str + 1);
761
762 if (!digit
763 || (base == 16 && !isxdigit(digit))
764 || (base == 10 && !isdigit(digit))
765 || (base == 8 && (!isdigit(digit) || digit > '7'))
766 || (base == 0 && !isdigit(digit)))
767 break;
768
769 switch(qualifier) {
770 case 'H': /* that's 'hh' in format */
771 if (is_sign) {
772 signed char *s = (signed char *) va_arg(args,signed char *);
773 *s = (signed char) simple_strtol(str,&next,base);
774 } else {
775 unsigned char *s = (unsigned char *) va_arg(args, unsigned char *);
776 *s = (unsigned char) simple_strtoul(str, &next, base);
777 }
778 break;
779 case 'h':
780 if (is_sign) {
781 short *s = (short *) va_arg(args,short *);
782 *s = (short) simple_strtol(str,&next,base);
783 } else {
784 unsigned short *s = (unsigned short *) va_arg(args, unsigned short *);
785 *s = (unsigned short) simple_strtoul(str, &next, base);
786 }
787 break;
788 case 'l':
789 if (is_sign) {
790 long *l = (long *) va_arg(args,long *);
791 *l = simple_strtol(str,&next,base);
792 } else {
793 unsigned long *l = (unsigned long*) va_arg(args,unsigned long*);
794 *l = simple_strtoul(str,&next,base);
795 }
796 break;
797 case 'L':
798 if (is_sign) {
799 long long *l = (long long*) va_arg(args,long long *);
800 *l = simple_strtoll(str,&next,base);
801 } else {
802 unsigned long long *l = (unsigned long long*) va_arg(args,unsigned long long*);
803 *l = simple_strtoull(str,&next,base);
804 }
805 break;
806 case 'Z':
807 case 'z':
808 {
809 size_t *s = (size_t*) va_arg(args,size_t*);
810 *s = (size_t) simple_strtoul(str,&next,base);
811 }
812 break;
813 default:
814 if (is_sign) {
815 int *i = (int *) va_arg(args, int*);
816 *i = (int) simple_strtol(str,&next,base);
817 } else {
818 unsigned int *i = (unsigned int*) va_arg(args, unsigned int*);
819 *i = (unsigned int) simple_strtoul(str,&next,base);
820 }
821 break;
822 }
823 num++;
824
825 if (!next)
826 break;
827 str = next;
828 }
829 return num;
830}
831
832EXPORT_SYMBOL(vsscanf);
833
834/**
835 * sscanf - Unformat a buffer into a list of arguments
836 * @buf: input buffer
837 * @fmt: formatting of buffer
838 * @...: resulting arguments
839 */
840int sscanf(const char * buf, const char * fmt, ...)
841{
842 va_list args;
843 int i;
844
845 va_start(args,fmt);
846 i = vsscanf(buf,fmt,args);
847 va_end(args);
848 return i;
849}
850
851EXPORT_SYMBOL(sscanf);
852
853
854/* Simplified asprintf. */
855char *kasprintf(gfp_t gfp, const char *fmt, ...)
856{
857 va_list ap;
858 unsigned int len;
859 char *p;
860
861 va_start(ap, fmt);
862 len = vsnprintf(NULL, 0, fmt, ap);
863 va_end(ap);
864
865 p = kmalloc(len+1, gfp);
866 if (!p)
867 return NULL;
868 va_start(ap, fmt);
869 vsnprintf(p, len+1, fmt, ap);
870 va_end(ap);
871 return p;
872}
873
874EXPORT_SYMBOL(kasprintf);