blob: 419993f58c6b6d61c7f881b90508ade03312085e [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
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 <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
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
Tim Schmielau4e57b682005-10-30 15:03:48 -080026#include <asm/page.h> /* for PAGE_SIZE */
Linus Torvalds1da177e2005-04-16 15:20:36 -070027#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
Yi Yang06b2a762008-02-08 04:21:57 -0800129
130/**
131 * strict_strtoul - convert a string to an unsigned long strictly
132 * @cp: The string to be converted
133 * @base: The number base to use
134 * @res: The converted result value
135 *
136 * strict_strtoul converts a string to an unsigned long only if the
137 * string is really an unsigned long string, any string containing
138 * any invalid char at the tail will be rejected and -EINVAL is returned,
139 * only a newline char at the tail is acceptible because people generally
140 * change a module parameter in the following way:
141 *
142 * echo 1024 > /sys/module/e1000/parameters/copybreak
143 *
144 * echo will append a newline to the tail.
145 *
146 * It returns 0 if conversion is successful and *res is set to the converted
147 * value, otherwise it returns -EINVAL and *res is set to 0.
148 *
149 * simple_strtoul just ignores the successive invalid characters and
150 * return the converted value of prefix part of the string.
151 */
152int strict_strtoul(const char *cp, unsigned int base, unsigned long *res);
153
154/**
155 * strict_strtol - convert a string to a long strictly
156 * @cp: The string to be converted
157 * @base: The number base to use
158 * @res: The converted result value
159 *
160 * strict_strtol is similiar to strict_strtoul, but it allows the first
161 * character of a string is '-'.
162 *
163 * It returns 0 if conversion is successful and *res is set to the converted
164 * value, otherwise it returns -EINVAL and *res is set to 0.
165 */
166int strict_strtol(const char *cp, unsigned int base, long *res);
167
168/**
169 * strict_strtoull - convert a string to an unsigned long long strictly
170 * @cp: The string to be converted
171 * @base: The number base to use
172 * @res: The converted result value
173 *
174 * strict_strtoull converts a string to an unsigned long long only if the
175 * string is really an unsigned long long string, any string containing
176 * any invalid char at the tail will be rejected and -EINVAL is returned,
177 * only a newline char at the tail is acceptible because people generally
178 * change a module parameter in the following way:
179 *
180 * echo 1024 > /sys/module/e1000/parameters/copybreak
181 *
182 * echo will append a newline to the tail of the string.
183 *
184 * It returns 0 if conversion is successful and *res is set to the converted
185 * value, otherwise it returns -EINVAL and *res is set to 0.
186 *
187 * simple_strtoull just ignores the successive invalid characters and
188 * return the converted value of prefix part of the string.
189 */
190int strict_strtoull(const char *cp, unsigned int base, unsigned long long *res);
191
192/**
193 * strict_strtoll - convert a string to a long long strictly
194 * @cp: The string to be converted
195 * @base: The number base to use
196 * @res: The converted result value
197 *
198 * strict_strtoll is similiar to strict_strtoull, but it allows the first
199 * character of a string is '-'.
200 *
201 * It returns 0 if conversion is successful and *res is set to the converted
202 * value, otherwise it returns -EINVAL and *res is set to 0.
203 */
204int strict_strtoll(const char *cp, unsigned int base, long long *res);
205
206#define define_strict_strtoux(type, valtype) \
207int strict_strtou##type(const char *cp, unsigned int base, valtype *res)\
208{ \
209 char *tail; \
210 valtype val; \
211 size_t len; \
212 \
213 *res = 0; \
214 len = strlen(cp); \
215 if (len == 0) \
216 return -EINVAL; \
217 \
218 val = simple_strtoul(cp, &tail, base); \
219 if ((*tail == '\0') || \
220 ((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) {\
221 *res = val; \
222 return 0; \
223 } \
224 \
225 return -EINVAL; \
226} \
227
228#define define_strict_strtox(type, valtype) \
229int strict_strto##type(const char *cp, unsigned int base, valtype *res) \
230{ \
231 int ret; \
232 if (*cp == '-') { \
233 ret = strict_strtou##type(cp+1, base, res); \
234 if (ret != 0) \
235 *res = -(*res); \
236 } else \
237 ret = strict_strtou##type(cp, base, res); \
238 \
239 return ret; \
240} \
241
242define_strict_strtoux(l, unsigned long)
243define_strict_strtox(l, long)
244define_strict_strtoux(ll, unsigned long long)
245define_strict_strtox(ll, long long)
246
247EXPORT_SYMBOL(strict_strtoul);
248EXPORT_SYMBOL(strict_strtol);
249EXPORT_SYMBOL(strict_strtoll);
250EXPORT_SYMBOL(strict_strtoull);
251
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252static int skip_atoi(const char **s)
253{
254 int i=0;
255
256 while (isdigit(**s))
257 i = i*10 + *((*s)++) - '0';
258 return i;
259}
260
Denis Vlasenko4277eed2007-07-15 23:41:56 -0700261/* Decimal conversion is by far the most typical, and is used
262 * for /proc and /sys data. This directly impacts e.g. top performance
263 * with many processes running. We optimize it for speed
264 * using code from
265 * http://www.cs.uiowa.edu/~jones/bcd/decimal.html
266 * (with permission from the author, Douglas W. Jones). */
267
268/* Formats correctly any integer in [0,99999].
269 * Outputs from one to five digits depending on input.
270 * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */
271static char* put_dec_trunc(char *buf, unsigned q)
272{
273 unsigned d3, d2, d1, d0;
274 d1 = (q>>4) & 0xf;
275 d2 = (q>>8) & 0xf;
276 d3 = (q>>12);
277
278 d0 = 6*(d3 + d2 + d1) + (q & 0xf);
279 q = (d0 * 0xcd) >> 11;
280 d0 = d0 - 10*q;
281 *buf++ = d0 + '0'; /* least significant digit */
282 d1 = q + 9*d3 + 5*d2 + d1;
283 if (d1 != 0) {
284 q = (d1 * 0xcd) >> 11;
285 d1 = d1 - 10*q;
286 *buf++ = d1 + '0'; /* next digit */
287
288 d2 = q + 2*d2;
289 if ((d2 != 0) || (d3 != 0)) {
290 q = (d2 * 0xd) >> 7;
291 d2 = d2 - 10*q;
292 *buf++ = d2 + '0'; /* next digit */
293
294 d3 = q + 4*d3;
295 if (d3 != 0) {
296 q = (d3 * 0xcd) >> 11;
297 d3 = d3 - 10*q;
298 *buf++ = d3 + '0'; /* next digit */
299 if (q != 0)
300 *buf++ = q + '0'; /* most sign. digit */
301 }
302 }
303 }
304 return buf;
305}
306/* Same with if's removed. Always emits five digits */
307static char* put_dec_full(char *buf, unsigned q)
308{
309 /* BTW, if q is in [0,9999], 8-bit ints will be enough, */
310 /* but anyway, gcc produces better code with full-sized ints */
311 unsigned d3, d2, d1, d0;
312 d1 = (q>>4) & 0xf;
313 d2 = (q>>8) & 0xf;
314 d3 = (q>>12);
315
316 /* Possible ways to approx. divide by 10 */
317 /* gcc -O2 replaces multiply with shifts and adds */
318 // (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
319 // (x * 0x67) >> 10: 1100111
320 // (x * 0x34) >> 9: 110100 - same
321 // (x * 0x1a) >> 8: 11010 - same
322 // (x * 0x0d) >> 7: 1101 - same, shortest code (on i386)
323
324 d0 = 6*(d3 + d2 + d1) + (q & 0xf);
325 q = (d0 * 0xcd) >> 11;
326 d0 = d0 - 10*q;
327 *buf++ = d0 + '0';
328 d1 = q + 9*d3 + 5*d2 + d1;
329 q = (d1 * 0xcd) >> 11;
330 d1 = d1 - 10*q;
331 *buf++ = d1 + '0';
332
333 d2 = q + 2*d2;
334 q = (d2 * 0xd) >> 7;
335 d2 = d2 - 10*q;
336 *buf++ = d2 + '0';
337
338 d3 = q + 4*d3;
339 q = (d3 * 0xcd) >> 11; /* - shorter code */
340 /* q = (d3 * 0x67) >> 10; - would also work */
341 d3 = d3 - 10*q;
342 *buf++ = d3 + '0';
343 *buf++ = q + '0';
344 return buf;
345}
346/* No inlining helps gcc to use registers better */
347static noinline char* put_dec(char *buf, unsigned long long num)
348{
349 while (1) {
350 unsigned rem;
351 if (num < 100000)
352 return put_dec_trunc(buf, num);
353 rem = do_div(num, 100000);
354 buf = put_dec_full(buf, rem);
355 }
356}
357
Linus Torvalds1da177e2005-04-16 15:20:36 -0700358#define ZEROPAD 1 /* pad with zero */
359#define SIGN 2 /* unsigned/signed long */
360#define PLUS 4 /* show plus */
361#define SPACE 8 /* space if plus */
362#define LEFT 16 /* left justified */
363#define SPECIAL 32 /* 0x */
364#define LARGE 64 /* use 'ABCDEF' instead of 'abcdef' */
365
Denis Vlasenkob39a7342007-07-15 23:41:54 -0700366static char *number(char *buf, char *end, unsigned long long num, int base, int size, int precision, int type)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700367{
Denis Vlasenkob39a7342007-07-15 23:41:54 -0700368 char sign,tmp[66];
Linus Torvalds1da177e2005-04-16 15:20:36 -0700369 const char *digits;
Denis Vlasenkob39a7342007-07-15 23:41:54 -0700370 /* we are called with base 8, 10 or 16, only, thus don't need "g..." */
371 static const char small_digits[] = "0123456789abcdefx"; /* "ghijklmnopqrstuvwxyz"; */
372 static const char large_digits[] = "0123456789ABCDEFX"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
373 int need_pfx = ((type & SPECIAL) && base != 10);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700374 int i;
375
376 digits = (type & LARGE) ? large_digits : small_digits;
377 if (type & LEFT)
378 type &= ~ZEROPAD;
379 if (base < 2 || base > 36)
380 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700381 sign = 0;
382 if (type & SIGN) {
383 if ((signed long long) num < 0) {
384 sign = '-';
385 num = - (signed long long) num;
386 size--;
387 } else if (type & PLUS) {
388 sign = '+';
389 size--;
390 } else if (type & SPACE) {
391 sign = ' ';
392 size--;
393 }
394 }
Denis Vlasenkob39a7342007-07-15 23:41:54 -0700395 if (need_pfx) {
396 size--;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700397 if (base == 16)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700398 size--;
399 }
Denis Vlasenkob39a7342007-07-15 23:41:54 -0700400
401 /* generate full string in tmp[], in reverse order */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700402 i = 0;
403 if (num == 0)
Denis Vlasenkob39a7342007-07-15 23:41:54 -0700404 tmp[i++] = '0';
Denis Vlasenko4277eed2007-07-15 23:41:56 -0700405 /* Generic code, for any base:
406 else do {
407 tmp[i++] = digits[do_div(num,base)];
408 } while (num != 0);
409 */
Denis Vlasenkob39a7342007-07-15 23:41:54 -0700410 else if (base != 10) { /* 8 or 16 */
411 int mask = base - 1;
412 int shift = 3;
413 if (base == 16) shift = 4;
414 do {
415 tmp[i++] = digits[((unsigned char)num) & mask];
416 num >>= shift;
417 } while (num);
Denis Vlasenko4277eed2007-07-15 23:41:56 -0700418 } else { /* base 10 */
419 i = put_dec(tmp, num) - tmp;
420 }
Denis Vlasenkob39a7342007-07-15 23:41:54 -0700421
422 /* printing 100 using %2d gives "100", not "00" */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700423 if (i > precision)
424 precision = i;
Denis Vlasenkob39a7342007-07-15 23:41:54 -0700425 /* leading space padding */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700426 size -= precision;
Denis Vlasenkob39a7342007-07-15 23:41:54 -0700427 if (!(type & (ZEROPAD+LEFT))) {
428 while(--size >= 0) {
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700429 if (buf < end)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700430 *buf = ' ';
431 ++buf;
432 }
433 }
Denis Vlasenkob39a7342007-07-15 23:41:54 -0700434 /* sign */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700435 if (sign) {
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700436 if (buf < end)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437 *buf = sign;
438 ++buf;
439 }
Denis Vlasenkob39a7342007-07-15 23:41:54 -0700440 /* "0x" / "0" prefix */
441 if (need_pfx) {
442 if (buf < end)
443 *buf = '0';
444 ++buf;
445 if (base == 16) {
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700446 if (buf < end)
Denis Vlasenkob39a7342007-07-15 23:41:54 -0700447 *buf = digits[16]; /* for arbitrary base: digits[33]; */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700448 ++buf;
449 }
450 }
Denis Vlasenkob39a7342007-07-15 23:41:54 -0700451 /* zero or space padding */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700452 if (!(type & LEFT)) {
Denis Vlasenkob39a7342007-07-15 23:41:54 -0700453 char c = (type & ZEROPAD) ? '0' : ' ';
454 while (--size >= 0) {
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700455 if (buf < end)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700456 *buf = c;
457 ++buf;
458 }
459 }
Denis Vlasenkob39a7342007-07-15 23:41:54 -0700460 /* hmm even more zero padding? */
461 while (i <= --precision) {
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700462 if (buf < end)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700463 *buf = '0';
464 ++buf;
465 }
Denis Vlasenkob39a7342007-07-15 23:41:54 -0700466 /* actual digits of result */
467 while (--i >= 0) {
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700468 if (buf < end)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700469 *buf = tmp[i];
470 ++buf;
471 }
Denis Vlasenkob39a7342007-07-15 23:41:54 -0700472 /* trailing space padding */
473 while (--size >= 0) {
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700474 if (buf < end)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700475 *buf = ' ';
476 ++buf;
477 }
478 return buf;
479}
480
481/**
482 * vsnprintf - Format a string and place it in a buffer
483 * @buf: The buffer to place the result into
484 * @size: The size of the buffer, including the trailing null space
485 * @fmt: The format string to use
486 * @args: Arguments for the format string
487 *
488 * The return value is the number of characters which would
489 * be generated for the given input, excluding the trailing
490 * '\0', as per ISO C99. If you want to have the exact
491 * number of characters written into @buf as return value
Robert P. J. Day72fd4a32007-02-10 01:45:59 -0800492 * (not including the trailing '\0'), use vscnprintf(). If the
Linus Torvalds1da177e2005-04-16 15:20:36 -0700493 * return is greater than or equal to @size, the resulting
494 * string is truncated.
495 *
496 * Call this function if you are already dealing with a va_list.
Robert P. J. Day72fd4a32007-02-10 01:45:59 -0800497 * You probably want snprintf() instead.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498 */
499int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
500{
501 int len;
502 unsigned long long num;
503 int i, base;
504 char *str, *end, c;
505 const char *s;
506
507 int flags; /* flags to number() */
508
509 int field_width; /* width of output field */
510 int precision; /* min. # of digits for integers; max
511 number of chars for from string */
512 int qualifier; /* 'h', 'l', or 'L' for integer fields */
513 /* 'z' support added 23/7/1999 S.H. */
514 /* 'z' changed to 'Z' --davidm 1/25/99 */
Al Viro80322302005-08-23 22:48:17 +0100515 /* 't' added for ptrdiff_t */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700516
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700517 /* Reject out-of-range values early. Large positive sizes are
518 used for unknown buffer sizes. */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700519 if (unlikely((int) size < 0)) {
520 /* There can be only one.. */
Denis Vlasenkob39a7342007-07-15 23:41:54 -0700521 static char warn = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700522 WARN_ON(warn);
523 warn = 0;
524 return 0;
525 }
526
527 str = buf;
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700528 end = buf + size;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700529
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700530 /* Make sure end is always >= buf */
531 if (end < buf) {
532 end = ((void *)-1);
533 size = end - buf;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700534 }
535
536 for (; *fmt ; ++fmt) {
537 if (*fmt != '%') {
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700538 if (str < end)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700539 *str = *fmt;
540 ++str;
541 continue;
542 }
543
544 /* process flags */
545 flags = 0;
546 repeat:
547 ++fmt; /* this also skips first '%' */
548 switch (*fmt) {
549 case '-': flags |= LEFT; goto repeat;
550 case '+': flags |= PLUS; goto repeat;
551 case ' ': flags |= SPACE; goto repeat;
552 case '#': flags |= SPECIAL; goto repeat;
553 case '0': flags |= ZEROPAD; goto repeat;
554 }
555
556 /* get field width */
557 field_width = -1;
558 if (isdigit(*fmt))
559 field_width = skip_atoi(&fmt);
560 else if (*fmt == '*') {
561 ++fmt;
562 /* it's the next argument */
563 field_width = va_arg(args, int);
564 if (field_width < 0) {
565 field_width = -field_width;
566 flags |= LEFT;
567 }
568 }
569
570 /* get the precision */
571 precision = -1;
572 if (*fmt == '.') {
573 ++fmt;
574 if (isdigit(*fmt))
575 precision = skip_atoi(&fmt);
576 else if (*fmt == '*') {
577 ++fmt;
578 /* it's the next argument */
579 precision = va_arg(args, int);
580 }
581 if (precision < 0)
582 precision = 0;
583 }
584
585 /* get the conversion qualifier */
586 qualifier = -1;
587 if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
Al Viro80322302005-08-23 22:48:17 +0100588 *fmt =='Z' || *fmt == 'z' || *fmt == 't') {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700589 qualifier = *fmt;
590 ++fmt;
591 if (qualifier == 'l' && *fmt == 'l') {
592 qualifier = 'L';
593 ++fmt;
594 }
595 }
596
597 /* default base */
598 base = 10;
599
600 switch (*fmt) {
601 case 'c':
602 if (!(flags & LEFT)) {
603 while (--field_width > 0) {
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700604 if (str < end)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700605 *str = ' ';
606 ++str;
607 }
608 }
609 c = (unsigned char) va_arg(args, int);
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700610 if (str < end)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700611 *str = c;
612 ++str;
613 while (--field_width > 0) {
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700614 if (str < end)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615 *str = ' ';
616 ++str;
617 }
618 continue;
619
620 case 's':
621 s = va_arg(args, char *);
622 if ((unsigned long)s < PAGE_SIZE)
623 s = "<NULL>";
624
625 len = strnlen(s, precision);
626
627 if (!(flags & LEFT)) {
628 while (len < field_width--) {
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700629 if (str < end)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700630 *str = ' ';
631 ++str;
632 }
633 }
634 for (i = 0; i < len; ++i) {
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700635 if (str < end)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700636 *str = *s;
637 ++str; ++s;
638 }
639 while (len < field_width--) {
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700640 if (str < end)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700641 *str = ' ';
642 ++str;
643 }
644 continue;
645
646 case 'p':
647 if (field_width == -1) {
648 field_width = 2*sizeof(void *);
649 flags |= ZEROPAD;
650 }
651 str = number(str, end,
652 (unsigned long) va_arg(args, void *),
653 16, field_width, precision, flags);
654 continue;
655
656
657 case 'n':
658 /* FIXME:
659 * What does C99 say about the overflow case here? */
660 if (qualifier == 'l') {
661 long * ip = va_arg(args, long *);
662 *ip = (str - buf);
663 } else if (qualifier == 'Z' || qualifier == 'z') {
664 size_t * ip = va_arg(args, size_t *);
665 *ip = (str - buf);
666 } else {
667 int * ip = va_arg(args, int *);
668 *ip = (str - buf);
669 }
670 continue;
671
672 case '%':
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700673 if (str < end)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700674 *str = '%';
675 ++str;
676 continue;
677
678 /* integer number formats - set up the flags and "break" */
679 case 'o':
680 base = 8;
681 break;
682
683 case 'X':
684 flags |= LARGE;
685 case 'x':
686 base = 16;
687 break;
688
689 case 'd':
690 case 'i':
691 flags |= SIGN;
692 case 'u':
693 break;
694
695 default:
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700696 if (str < end)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700697 *str = '%';
698 ++str;
699 if (*fmt) {
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700700 if (str < end)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700701 *str = *fmt;
702 ++str;
703 } else {
704 --fmt;
705 }
706 continue;
707 }
708 if (qualifier == 'L')
709 num = va_arg(args, long long);
710 else if (qualifier == 'l') {
711 num = va_arg(args, unsigned long);
712 if (flags & SIGN)
713 num = (signed long) num;
714 } else if (qualifier == 'Z' || qualifier == 'z') {
715 num = va_arg(args, size_t);
Al Viro80322302005-08-23 22:48:17 +0100716 } else if (qualifier == 't') {
717 num = va_arg(args, ptrdiff_t);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700718 } else if (qualifier == 'h') {
719 num = (unsigned short) va_arg(args, int);
720 if (flags & SIGN)
721 num = (signed short) num;
722 } else {
723 num = va_arg(args, unsigned int);
724 if (flags & SIGN)
725 num = (signed int) num;
726 }
727 str = number(str, end, num, base,
728 field_width, precision, flags);
729 }
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700730 if (size > 0) {
731 if (str < end)
732 *str = '\0';
733 else
Linus Torvalds0a6047e2006-06-28 17:09:34 -0700734 end[-1] = '\0';
Jeremy Fitzhardingef7969372006-06-25 05:49:17 -0700735 }
736 /* the trailing null byte doesn't count towards the total */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700737 return str-buf;
738}
739
740EXPORT_SYMBOL(vsnprintf);
741
742/**
743 * vscnprintf - Format a string and place it in a buffer
744 * @buf: The buffer to place the result into
745 * @size: The size of the buffer, including the trailing null space
746 * @fmt: The format string to use
747 * @args: Arguments for the format string
748 *
749 * The return value is the number of characters which have been written into
750 * the @buf not including the trailing '\0'. If @size is <= 0 the function
751 * returns 0.
752 *
753 * Call this function if you are already dealing with a va_list.
Robert P. J. Day72fd4a32007-02-10 01:45:59 -0800754 * You probably want scnprintf() instead.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700755 */
756int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
757{
758 int i;
759
760 i=vsnprintf(buf,size,fmt,args);
761 return (i >= size) ? (size - 1) : i;
762}
763
764EXPORT_SYMBOL(vscnprintf);
765
766/**
767 * snprintf - Format a string and place it in a buffer
768 * @buf: The buffer to place the result into
769 * @size: The size of the buffer, including the trailing null space
770 * @fmt: The format string to use
771 * @...: Arguments for the format string
772 *
773 * The return value is the number of characters which would be
774 * generated for the given input, excluding the trailing null,
775 * as per ISO C99. If the return is greater than or equal to
776 * @size, the resulting string is truncated.
777 */
778int snprintf(char * buf, size_t size, const char *fmt, ...)
779{
780 va_list args;
781 int i;
782
783 va_start(args, fmt);
784 i=vsnprintf(buf,size,fmt,args);
785 va_end(args);
786 return i;
787}
788
789EXPORT_SYMBOL(snprintf);
790
791/**
792 * scnprintf - Format a string and place it in a buffer
793 * @buf: The buffer to place the result into
794 * @size: The size of the buffer, including the trailing null space
795 * @fmt: The format string to use
796 * @...: Arguments for the format string
797 *
798 * The return value is the number of characters written into @buf not including
Martin Peschkeea6f3282007-02-12 00:51:56 -0800799 * the trailing '\0'. If @size is <= 0 the function returns 0.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700800 */
801
802int scnprintf(char * buf, size_t size, const char *fmt, ...)
803{
804 va_list args;
805 int i;
806
807 va_start(args, fmt);
808 i = vsnprintf(buf, size, fmt, args);
809 va_end(args);
810 return (i >= size) ? (size - 1) : i;
811}
812EXPORT_SYMBOL(scnprintf);
813
814/**
815 * vsprintf - Format a string and place it in a buffer
816 * @buf: The buffer to place the result into
817 * @fmt: The format string to use
818 * @args: Arguments for the format string
819 *
820 * The function returns the number of characters written
Robert P. J. Day72fd4a32007-02-10 01:45:59 -0800821 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
Linus Torvalds1da177e2005-04-16 15:20:36 -0700822 * buffer overflows.
823 *
824 * Call this function if you are already dealing with a va_list.
Robert P. J. Day72fd4a32007-02-10 01:45:59 -0800825 * You probably want sprintf() instead.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700826 */
827int vsprintf(char *buf, const char *fmt, va_list args)
828{
829 return vsnprintf(buf, INT_MAX, fmt, args);
830}
831
832EXPORT_SYMBOL(vsprintf);
833
834/**
835 * sprintf - Format a string and place it in a buffer
836 * @buf: The buffer to place the result into
837 * @fmt: The format string to use
838 * @...: Arguments for the format string
839 *
840 * The function returns the number of characters written
Robert P. J. Day72fd4a32007-02-10 01:45:59 -0800841 * into @buf. Use snprintf() or scnprintf() in order to avoid
Linus Torvalds1da177e2005-04-16 15:20:36 -0700842 * buffer overflows.
843 */
844int sprintf(char * buf, const char *fmt, ...)
845{
846 va_list args;
847 int i;
848
849 va_start(args, fmt);
850 i=vsnprintf(buf, INT_MAX, fmt, args);
851 va_end(args);
852 return i;
853}
854
855EXPORT_SYMBOL(sprintf);
856
857/**
858 * vsscanf - Unformat a buffer into a list of arguments
859 * @buf: input buffer
860 * @fmt: format of buffer
861 * @args: arguments
862 */
863int vsscanf(const char * buf, const char * fmt, va_list args)
864{
865 const char *str = buf;
866 char *next;
867 char digit;
868 int num = 0;
869 int qualifier;
870 int base;
871 int field_width;
872 int is_sign = 0;
873
874 while(*fmt && *str) {
875 /* skip any white space in format */
876 /* white space in format matchs any amount of
877 * white space, including none, in the input.
878 */
879 if (isspace(*fmt)) {
880 while (isspace(*fmt))
881 ++fmt;
882 while (isspace(*str))
883 ++str;
884 }
885
886 /* anything that is not a conversion must match exactly */
887 if (*fmt != '%' && *fmt) {
888 if (*fmt++ != *str++)
889 break;
890 continue;
891 }
892
893 if (!*fmt)
894 break;
895 ++fmt;
896
897 /* skip this conversion.
898 * advance both strings to next white space
899 */
900 if (*fmt == '*') {
901 while (!isspace(*fmt) && *fmt)
902 fmt++;
903 while (!isspace(*str) && *str)
904 str++;
905 continue;
906 }
907
908 /* get field width */
909 field_width = -1;
910 if (isdigit(*fmt))
911 field_width = skip_atoi(&fmt);
912
913 /* get conversion qualifier */
914 qualifier = -1;
915 if (*fmt == 'h' || *fmt == 'l' || *fmt == 'L' ||
916 *fmt == 'Z' || *fmt == 'z') {
917 qualifier = *fmt++;
918 if (unlikely(qualifier == *fmt)) {
919 if (qualifier == 'h') {
920 qualifier = 'H';
921 fmt++;
922 } else if (qualifier == 'l') {
923 qualifier = 'L';
924 fmt++;
925 }
926 }
927 }
928 base = 10;
929 is_sign = 0;
930
931 if (!*fmt || !*str)
932 break;
933
934 switch(*fmt++) {
935 case 'c':
936 {
937 char *s = (char *) va_arg(args,char*);
938 if (field_width == -1)
939 field_width = 1;
940 do {
941 *s++ = *str++;
942 } while (--field_width > 0 && *str);
943 num++;
944 }
945 continue;
946 case 's':
947 {
948 char *s = (char *) va_arg(args, char *);
949 if(field_width == -1)
950 field_width = INT_MAX;
951 /* first, skip leading white space in buffer */
952 while (isspace(*str))
953 str++;
954
955 /* now copy until next white space */
956 while (*str && !isspace(*str) && field_width--) {
957 *s++ = *str++;
958 }
959 *s = '\0';
960 num++;
961 }
962 continue;
963 case 'n':
964 /* return number of characters read so far */
965 {
966 int *i = (int *)va_arg(args,int*);
967 *i = str - buf;
968 }
969 continue;
970 case 'o':
971 base = 8;
972 break;
973 case 'x':
974 case 'X':
975 base = 16;
976 break;
977 case 'i':
978 base = 0;
979 case 'd':
980 is_sign = 1;
981 case 'u':
982 break;
983 case '%':
984 /* looking for '%' in str */
985 if (*str++ != '%')
986 return num;
987 continue;
988 default:
989 /* invalid format; stop here */
990 return num;
991 }
992
993 /* have some sort of integer conversion.
994 * first, skip white space in buffer.
995 */
996 while (isspace(*str))
997 str++;
998
999 digit = *str;
1000 if (is_sign && digit == '-')
1001 digit = *(str + 1);
1002
1003 if (!digit
1004 || (base == 16 && !isxdigit(digit))
1005 || (base == 10 && !isdigit(digit))
1006 || (base == 8 && (!isdigit(digit) || digit > '7'))
1007 || (base == 0 && !isdigit(digit)))
1008 break;
1009
1010 switch(qualifier) {
1011 case 'H': /* that's 'hh' in format */
1012 if (is_sign) {
1013 signed char *s = (signed char *) va_arg(args,signed char *);
1014 *s = (signed char) simple_strtol(str,&next,base);
1015 } else {
1016 unsigned char *s = (unsigned char *) va_arg(args, unsigned char *);
1017 *s = (unsigned char) simple_strtoul(str, &next, base);
1018 }
1019 break;
1020 case 'h':
1021 if (is_sign) {
1022 short *s = (short *) va_arg(args,short *);
1023 *s = (short) simple_strtol(str,&next,base);
1024 } else {
1025 unsigned short *s = (unsigned short *) va_arg(args, unsigned short *);
1026 *s = (unsigned short) simple_strtoul(str, &next, base);
1027 }
1028 break;
1029 case 'l':
1030 if (is_sign) {
1031 long *l = (long *) va_arg(args,long *);
1032 *l = simple_strtol(str,&next,base);
1033 } else {
1034 unsigned long *l = (unsigned long*) va_arg(args,unsigned long*);
1035 *l = simple_strtoul(str,&next,base);
1036 }
1037 break;
1038 case 'L':
1039 if (is_sign) {
1040 long long *l = (long long*) va_arg(args,long long *);
1041 *l = simple_strtoll(str,&next,base);
1042 } else {
1043 unsigned long long *l = (unsigned long long*) va_arg(args,unsigned long long*);
1044 *l = simple_strtoull(str,&next,base);
1045 }
1046 break;
1047 case 'Z':
1048 case 'z':
1049 {
1050 size_t *s = (size_t*) va_arg(args,size_t*);
1051 *s = (size_t) simple_strtoul(str,&next,base);
1052 }
1053 break;
1054 default:
1055 if (is_sign) {
1056 int *i = (int *) va_arg(args, int*);
1057 *i = (int) simple_strtol(str,&next,base);
1058 } else {
1059 unsigned int *i = (unsigned int*) va_arg(args, unsigned int*);
1060 *i = (unsigned int) simple_strtoul(str,&next,base);
1061 }
1062 break;
1063 }
1064 num++;
1065
1066 if (!next)
1067 break;
1068 str = next;
1069 }
Johannes Bergc6b40d12007-05-08 00:27:20 -07001070
1071 /*
1072 * Now we've come all the way through so either the input string or the
1073 * format ended. In the former case, there can be a %n at the current
1074 * position in the format that needs to be filled.
1075 */
1076 if (*fmt == '%' && *(fmt + 1) == 'n') {
1077 int *p = (int *)va_arg(args, int *);
1078 *p = str - buf;
1079 }
1080
Linus Torvalds1da177e2005-04-16 15:20:36 -07001081 return num;
1082}
1083
1084EXPORT_SYMBOL(vsscanf);
1085
1086/**
1087 * sscanf - Unformat a buffer into a list of arguments
1088 * @buf: input buffer
1089 * @fmt: formatting of buffer
1090 * @...: resulting arguments
1091 */
1092int sscanf(const char * buf, const char * fmt, ...)
1093{
1094 va_list args;
1095 int i;
1096
1097 va_start(args,fmt);
1098 i = vsscanf(buf,fmt,args);
1099 va_end(args);
1100 return i;
1101}
1102
1103EXPORT_SYMBOL(sscanf);