4 * Copyright (C) 1991, 1992 Linus Torvalds
7 /* vsprintf.c -- Lars Wirzenius & Linus Torvalds. */
9 * Wirzenius wrote this portably, Torvalds fucked it up :-)
13 * Fri Jul 13 2001 Crutcher Dunnavant <crutcher+kernel@datastacks.com>
14 * - changed to provide snprintf and vsnprintf functions
15 * So Feb 1 16:51:32 CET 2004 Juergen Quade <quade@hsnr.de>
16 * - scnprintf and vscnprintf
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>
26 #include <asm/page.h> /* for PAGE_SIZE */
27 #include <asm/div64.h>
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
35 unsigned long simple_strtoul(const char *cp,char **endp,unsigned int base)
37 unsigned long result = 0,value;
44 if ((toupper(*cp) == 'X') && isxdigit(cp[1])) {
49 } else if (base == 16) {
50 if (cp[0] == '0' && toupper(cp[1]) == 'X')
53 while (isxdigit(*cp) &&
54 (value = isdigit(*cp) ? *cp-'0' : toupper(*cp)-'A'+10) < base) {
55 result = result*base + value;
63 EXPORT_SYMBOL(simple_strtoul);
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
71 long simple_strtol(const char *cp,char **endp,unsigned int base)
74 return -simple_strtoul(cp+1,endp,base);
75 return simple_strtoul(cp,endp,base);
78 EXPORT_SYMBOL(simple_strtol);
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
86 unsigned long long simple_strtoull(const char *cp,char **endp,unsigned int base)
88 unsigned long long result = 0,value;
95 if ((toupper(*cp) == 'X') && isxdigit(cp[1])) {
100 } else if (base == 16) {
101 if (cp[0] == '0' && toupper(cp[1]) == 'X')
104 while (isxdigit(*cp) && (value = isdigit(*cp) ? *cp-'0' : (islower(*cp)
105 ? toupper(*cp) : *cp)-'A'+10) < base) {
106 result = result*base + value;
114 EXPORT_SYMBOL(simple_strtoull);
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
122 long long simple_strtoll(const char *cp,char **endp,unsigned int base)
125 return -simple_strtoull(cp+1,endp,base);
126 return simple_strtoull(cp,endp,base);
129 static int skip_atoi(const char **s)
134 i = i*10 + *((*s)++) - '0';
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' */
146 static char * number(char * buf, char * end, unsigned long long num, int base, int size, int precision, int type)
150 static const char small_digits[] = "0123456789abcdefghijklmnopqrstuvwxyz";
151 static const char large_digits[] = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZ";
154 digits = (type & LARGE) ? large_digits : small_digits;
157 if (base < 2 || base > 36)
159 c = (type & ZEROPAD) ? '0' : ' ';
162 if ((signed long long) num < 0) {
164 num = - (signed long long) num;
166 } else if (type & PLUS) {
169 } else if (type & SPACE) {
174 if (type & SPECIAL) {
183 else while (num != 0)
184 tmp[i++] = digits[do_div(num,base)];
188 if (!(type&(ZEROPAD+LEFT))) {
200 if (type & SPECIAL) {
205 } else if (base==16) {
214 if (!(type & LEFT)) {
221 while (i < precision--) {
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
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.
254 * Call this function if you are already dealing with a va_list.
255 * You probably want snprintf instead.
257 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
260 unsigned long long num;
265 int flags; /* flags to number() */
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 */
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.. */
288 /* Make sure end is always >= buf */
294 for (; *fmt ; ++fmt) {
305 ++fmt; /* this also skips first '%' */
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;
314 /* get field width */
317 field_width = skip_atoi(&fmt);
318 else if (*fmt == '*') {
320 /* it's the next argument */
321 field_width = va_arg(args, int);
322 if (field_width < 0) {
323 field_width = -field_width;
328 /* get the precision */
333 precision = skip_atoi(&fmt);
334 else if (*fmt == '*') {
336 /* it's the next argument */
337 precision = va_arg(args, int);
343 /* get the conversion qualifier */
345 if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
346 *fmt =='Z' || *fmt == 'z' || *fmt == 't') {
349 if (qualifier == 'l' && *fmt == 'l') {
360 if (!(flags & LEFT)) {
361 while (--field_width > 0) {
367 c = (unsigned char) va_arg(args, int);
371 while (--field_width > 0) {
379 s = va_arg(args, char *);
380 if ((unsigned long)s < PAGE_SIZE)
383 len = strnlen(s, precision);
385 if (!(flags & LEFT)) {
386 while (len < field_width--) {
392 for (i = 0; i < len; ++i) {
397 while (len < field_width--) {
405 if (field_width == -1) {
406 field_width = 2*sizeof(void *);
409 str = number(str, end,
410 (unsigned long) va_arg(args, void *),
411 16, field_width, precision, flags);
417 * What does C99 say about the overflow case here? */
418 if (qualifier == 'l') {
419 long * ip = va_arg(args, long *);
421 } else if (qualifier == 'Z' || qualifier == 'z') {
422 size_t * ip = va_arg(args, size_t *);
425 int * ip = va_arg(args, int *);
436 /* integer number formats - set up the flags and "break" */
466 if (qualifier == 'L')
467 num = va_arg(args, long long);
468 else if (qualifier == 'l') {
469 num = va_arg(args, unsigned long);
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);
479 num = (signed short) num;
481 num = va_arg(args, unsigned int);
483 num = (signed int) num;
485 str = number(str, end, num, base,
486 field_width, precision, flags);
494 /* the trailing null byte doesn't count towards the total */
498 EXPORT_SYMBOL(vsnprintf);
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
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
511 * Call this function if you are already dealing with a va_list.
512 * You probably want scnprintf instead.
514 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
518 i=vsnprintf(buf,size,fmt,args);
519 return (i >= size) ? (size - 1) : i;
522 EXPORT_SYMBOL(vscnprintf);
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
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.
536 int snprintf(char * buf, size_t size, const char *fmt, ...)
542 i=vsnprintf(buf,size,fmt,args);
547 EXPORT_SYMBOL(snprintf);
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
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.
561 int scnprintf(char * buf, size_t size, const char *fmt, ...)
567 i = vsnprintf(buf, size, fmt, args);
569 return (i >= size) ? (size - 1) : i;
571 EXPORT_SYMBOL(scnprintf);
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
579 * The function returns the number of characters written
580 * into @buf. Use vsnprintf or vscnprintf in order to avoid
583 * Call this function if you are already dealing with a va_list.
584 * You probably want sprintf instead.
586 int vsprintf(char *buf, const char *fmt, va_list args)
588 return vsnprintf(buf, INT_MAX, fmt, args);
591 EXPORT_SYMBOL(vsprintf);
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
599 * The function returns the number of characters written
600 * into @buf. Use snprintf or scnprintf in order to avoid
603 int sprintf(char * buf, const char *fmt, ...)
609 i=vsnprintf(buf, INT_MAX, fmt, args);
614 EXPORT_SYMBOL(sprintf);
617 * vsscanf - Unformat a buffer into a list of arguments
619 * @fmt: format of buffer
622 int vsscanf(const char * buf, const char * fmt, va_list args)
624 const char *str = buf;
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.
639 while (isspace(*fmt))
641 while (isspace(*str))
645 /* anything that is not a conversion must match exactly */
646 if (*fmt != '%' && *fmt) {
647 if (*fmt++ != *str++)
656 /* skip this conversion.
657 * advance both strings to next white space
660 while (!isspace(*fmt) && *fmt)
662 while (!isspace(*str) && *str)
667 /* get field width */
670 field_width = skip_atoi(&fmt);
672 /* get conversion qualifier */
674 if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
675 *fmt == 'Z' || *fmt == 'z') {
677 if (unlikely(qualifier == *fmt)) {
678 if (qualifier == 'h') {
681 } else if (qualifier == 'l') {
696 char *s = (char *) va_arg(args,char*);
697 if (field_width == -1)
701 } while (--field_width > 0 && *str);
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))
714 /* now copy until next white space */
715 while (*str && !isspace(*str) && field_width--) {
723 /* return number of characters read so far */
725 int *i = (int *)va_arg(args,int*);
743 /* looking for '%' in str */
748 /* invalid format; stop here */
752 /* have some sort of integer conversion.
753 * first, skip white space in buffer.
755 while (isspace(*str))
759 if (is_sign && digit == '-')
763 || (base == 16 && !isxdigit(digit))
764 || (base == 10 && !isdigit(digit))
765 || (base == 8 && (!isdigit(digit) || digit > '7'))
766 || (base == 0 && !isdigit(digit)))
770 case 'H': /* that's 'hh' in format */
772 signed char *s = (signed char *) va_arg(args,signed char *);
773 *s = (signed char) simple_strtol(str,&next,base);
775 unsigned char *s = (unsigned char *) va_arg(args, unsigned char *);
776 *s = (unsigned char) simple_strtoul(str, &next, base);
781 short *s = (short *) va_arg(args,short *);
782 *s = (short) simple_strtol(str,&next,base);
784 unsigned short *s = (unsigned short *) va_arg(args, unsigned short *);
785 *s = (unsigned short) simple_strtoul(str, &next, base);
790 long *l = (long *) va_arg(args,long *);
791 *l = simple_strtol(str,&next,base);
793 unsigned long *l = (unsigned long*) va_arg(args,unsigned long*);
794 *l = simple_strtoul(str,&next,base);
799 long long *l = (long long*) va_arg(args,long long *);
800 *l = simple_strtoll(str,&next,base);
802 unsigned long long *l = (unsigned long long*) va_arg(args,unsigned long long*);
803 *l = simple_strtoull(str,&next,base);
809 size_t *s = (size_t*) va_arg(args,size_t*);
810 *s = (size_t) simple_strtoul(str,&next,base);
815 int *i = (int *) va_arg(args, int*);
816 *i = (int) simple_strtol(str,&next,base);
818 unsigned int *i = (unsigned int*) va_arg(args, unsigned int*);
819 *i = (unsigned int) simple_strtoul(str,&next,base);
832 EXPORT_SYMBOL(vsscanf);
835 * sscanf - Unformat a buffer into a list of arguments
837 * @fmt: formatting of buffer
838 * @...: resulting arguments
840 int sscanf(const char * buf, const char * fmt, ...)
846 i = vsscanf(buf,fmt,args);
851 EXPORT_SYMBOL(sscanf);
854 /* Simplified asprintf. */
855 char *kasprintf(gfp_t gfp, const char *fmt, ...)
862 len = vsnprintf(NULL, 0, fmt, ap);
865 p = kmalloc(len+1, gfp);
869 vsnprintf(p, len+1, fmt, ap);
874 EXPORT_SYMBOL(kasprintf);