Root/lib/vsprintf.c

Source at commit b386be689295730688885552666ea40b2e639b14 created 8 years 11 months ago.
By Maarten ter Huurne, Revert "MIPS: JZ4740: reset: Initialize hibernate wakeup counters."
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 <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#include <linux/kallsyms.h>
26#include <linux/uaccess.h>
27#include <linux/ioport.h>
28#include <net/addrconf.h>
29
30#include <asm/page.h> /* for PAGE_SIZE */
31#include <asm/div64.h>
32#include <asm/sections.h> /* for dereference_function_descriptor() */
33
34#include "kstrtox.h"
35
36/**
37 * simple_strtoull - convert a string to an unsigned long long
38 * @cp: The start of the string
39 * @endp: A pointer to the end of the parsed string will be placed here
40 * @base: The number base to use
41 */
42unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base)
43{
44    unsigned long long result;
45    unsigned int rv;
46
47    cp = _parse_integer_fixup_radix(cp, &base);
48    rv = _parse_integer(cp, base, &result);
49    /* FIXME */
50    cp += (rv & ~KSTRTOX_OVERFLOW);
51
52    if (endp)
53        *endp = (char *)cp;
54
55    return result;
56}
57EXPORT_SYMBOL(simple_strtoull);
58
59/**
60 * simple_strtoul - convert a string to an unsigned long
61 * @cp: The start of the string
62 * @endp: A pointer to the end of the parsed string will be placed here
63 * @base: The number base to use
64 */
65unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base)
66{
67    return simple_strtoull(cp, endp, base);
68}
69EXPORT_SYMBOL(simple_strtoul);
70
71/**
72 * simple_strtol - convert a string to a signed long
73 * @cp: The start of the string
74 * @endp: A pointer to the end of the parsed string will be placed here
75 * @base: The number base to use
76 */
77long simple_strtol(const char *cp, char **endp, unsigned int base)
78{
79    if (*cp == '-')
80        return -simple_strtoul(cp + 1, endp, base);
81
82    return simple_strtoul(cp, endp, base);
83}
84EXPORT_SYMBOL(simple_strtol);
85
86/**
87 * simple_strtoll - convert a string to a signed long long
88 * @cp: The start of the string
89 * @endp: A pointer to the end of the parsed string will be placed here
90 * @base: The number base to use
91 */
92long long simple_strtoll(const char *cp, char **endp, unsigned int base)
93{
94    if (*cp == '-')
95        return -simple_strtoull(cp + 1, endp, base);
96
97    return simple_strtoull(cp, endp, base);
98}
99EXPORT_SYMBOL(simple_strtoll);
100
101static noinline_for_stack
102int skip_atoi(const char **s)
103{
104    int i = 0;
105
106    while (isdigit(**s))
107        i = i*10 + *((*s)++) - '0';
108
109    return i;
110}
111
112/* Decimal conversion is by far the most typical, and is used
113 * for /proc and /sys data. This directly impacts e.g. top performance
114 * with many processes running. We optimize it for speed
115 * using code from
116 * http://www.cs.uiowa.edu/~jones/bcd/decimal.html
117 * (with permission from the author, Douglas W. Jones). */
118
119/* Formats correctly any integer in [0,99999].
120 * Outputs from one to five digits depending on input.
121 * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */
122static noinline_for_stack
123char *put_dec_trunc(char *buf, unsigned q)
124{
125    unsigned d3, d2, d1, d0;
126    d1 = (q>>4) & 0xf;
127    d2 = (q>>8) & 0xf;
128    d3 = (q>>12);
129
130    d0 = 6*(d3 + d2 + d1) + (q & 0xf);
131    q = (d0 * 0xcd) >> 11;
132    d0 = d0 - 10*q;
133    *buf++ = d0 + '0'; /* least significant digit */
134    d1 = q + 9*d3 + 5*d2 + d1;
135    if (d1 != 0) {
136        q = (d1 * 0xcd) >> 11;
137        d1 = d1 - 10*q;
138        *buf++ = d1 + '0'; /* next digit */
139
140        d2 = q + 2*d2;
141        if ((d2 != 0) || (d3 != 0)) {
142            q = (d2 * 0xd) >> 7;
143            d2 = d2 - 10*q;
144            *buf++ = d2 + '0'; /* next digit */
145
146            d3 = q + 4*d3;
147            if (d3 != 0) {
148                q = (d3 * 0xcd) >> 11;
149                d3 = d3 - 10*q;
150                *buf++ = d3 + '0'; /* next digit */
151                if (q != 0)
152                    *buf++ = q + '0'; /* most sign. digit */
153            }
154        }
155    }
156
157    return buf;
158}
159/* Same with if's removed. Always emits five digits */
160static noinline_for_stack
161char *put_dec_full(char *buf, unsigned q)
162{
163    /* BTW, if q is in [0,9999], 8-bit ints will be enough, */
164    /* but anyway, gcc produces better code with full-sized ints */
165    unsigned d3, d2, d1, d0;
166    d1 = (q>>4) & 0xf;
167    d2 = (q>>8) & 0xf;
168    d3 = (q>>12);
169
170    /*
171     * Possible ways to approx. divide by 10
172     * gcc -O2 replaces multiply with shifts and adds
173     * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386)
174     * (x * 0x67) >> 10: 1100111
175     * (x * 0x34) >> 9: 110100 - same
176     * (x * 0x1a) >> 8: 11010 - same
177     * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386)
178     */
179    d0 = 6*(d3 + d2 + d1) + (q & 0xf);
180    q = (d0 * 0xcd) >> 11;
181    d0 = d0 - 10*q;
182    *buf++ = d0 + '0';
183    d1 = q + 9*d3 + 5*d2 + d1;
184        q = (d1 * 0xcd) >> 11;
185        d1 = d1 - 10*q;
186        *buf++ = d1 + '0';
187
188        d2 = q + 2*d2;
189            q = (d2 * 0xd) >> 7;
190            d2 = d2 - 10*q;
191            *buf++ = d2 + '0';
192
193            d3 = q + 4*d3;
194                q = (d3 * 0xcd) >> 11; /* - shorter code */
195                /* q = (d3 * 0x67) >> 10; - would also work */
196                d3 = d3 - 10*q;
197                *buf++ = d3 + '0';
198                    *buf++ = q + '0';
199
200    return buf;
201}
202/* No inlining helps gcc to use registers better */
203static noinline_for_stack
204char *put_dec(char *buf, unsigned long long num)
205{
206    while (1) {
207        unsigned rem;
208        if (num < 100000)
209            return put_dec_trunc(buf, num);
210        rem = do_div(num, 100000);
211        buf = put_dec_full(buf, rem);
212    }
213}
214
215#define ZEROPAD 1 /* pad with zero */
216#define SIGN 2 /* unsigned/signed long */
217#define PLUS 4 /* show plus */
218#define SPACE 8 /* space if plus */
219#define LEFT 16 /* left justified */
220#define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */
221#define SPECIAL 64 /* prefix hex with "0x", octal with "0" */
222
223enum format_type {
224    FORMAT_TYPE_NONE, /* Just a string part */
225    FORMAT_TYPE_WIDTH,
226    FORMAT_TYPE_PRECISION,
227    FORMAT_TYPE_CHAR,
228    FORMAT_TYPE_STR,
229    FORMAT_TYPE_PTR,
230    FORMAT_TYPE_PERCENT_CHAR,
231    FORMAT_TYPE_INVALID,
232    FORMAT_TYPE_LONG_LONG,
233    FORMAT_TYPE_ULONG,
234    FORMAT_TYPE_LONG,
235    FORMAT_TYPE_UBYTE,
236    FORMAT_TYPE_BYTE,
237    FORMAT_TYPE_USHORT,
238    FORMAT_TYPE_SHORT,
239    FORMAT_TYPE_UINT,
240    FORMAT_TYPE_INT,
241    FORMAT_TYPE_NRCHARS,
242    FORMAT_TYPE_SIZE_T,
243    FORMAT_TYPE_PTRDIFF
244};
245
246struct printf_spec {
247    u8 type; /* format_type enum */
248    u8 flags; /* flags to number() */
249    u8 base; /* number base, 8, 10 or 16 only */
250    u8 qualifier; /* number qualifier, one of 'hHlLtzZ' */
251    s16 field_width; /* width of output field */
252    s16 precision; /* # of digits/chars */
253};
254
255static noinline_for_stack
256char *number(char *buf, char *end, unsigned long long num,
257         struct printf_spec spec)
258{
259    /* we are called with base 8, 10 or 16, only, thus don't need "G..." */
260    static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */
261
262    char tmp[66];
263    char sign;
264    char locase;
265    int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10);
266    int i;
267
268    /* locase = 0 or 0x20. ORing digits or letters with 'locase'
269     * produces same digits or (maybe lowercased) letters */
270    locase = (spec.flags & SMALL);
271    if (spec.flags & LEFT)
272        spec.flags &= ~ZEROPAD;
273    sign = 0;
274    if (spec.flags & SIGN) {
275        if ((signed long long)num < 0) {
276            sign = '-';
277            num = -(signed long long)num;
278            spec.field_width--;
279        } else if (spec.flags & PLUS) {
280            sign = '+';
281            spec.field_width--;
282        } else if (spec.flags & SPACE) {
283            sign = ' ';
284            spec.field_width--;
285        }
286    }
287    if (need_pfx) {
288        spec.field_width--;
289        if (spec.base == 16)
290            spec.field_width--;
291    }
292
293    /* generate full string in tmp[], in reverse order */
294    i = 0;
295    if (num == 0)
296        tmp[i++] = '0';
297    /* Generic code, for any base:
298    else do {
299        tmp[i++] = (digits[do_div(num,base)] | locase);
300    } while (num != 0);
301    */
302    else if (spec.base != 10) { /* 8 or 16 */
303        int mask = spec.base - 1;
304        int shift = 3;
305
306        if (spec.base == 16)
307            shift = 4;
308        do {
309            tmp[i++] = (digits[((unsigned char)num) & mask] | locase);
310            num >>= shift;
311        } while (num);
312    } else { /* base 10 */
313        i = put_dec(tmp, num) - tmp;
314    }
315
316    /* printing 100 using %2d gives "100", not "00" */
317    if (i > spec.precision)
318        spec.precision = i;
319    /* leading space padding */
320    spec.field_width -= spec.precision;
321    if (!(spec.flags & (ZEROPAD+LEFT))) {
322        while (--spec.field_width >= 0) {
323            if (buf < end)
324                *buf = ' ';
325            ++buf;
326        }
327    }
328    /* sign */
329    if (sign) {
330        if (buf < end)
331            *buf = sign;
332        ++buf;
333    }
334    /* "0x" / "0" prefix */
335    if (need_pfx) {
336        if (buf < end)
337            *buf = '0';
338        ++buf;
339        if (spec.base == 16) {
340            if (buf < end)
341                *buf = ('X' | locase);
342            ++buf;
343        }
344    }
345    /* zero or space padding */
346    if (!(spec.flags & LEFT)) {
347        char c = (spec.flags & ZEROPAD) ? '0' : ' ';
348        while (--spec.field_width >= 0) {
349            if (buf < end)
350                *buf = c;
351            ++buf;
352        }
353    }
354    /* hmm even more zero padding? */
355    while (i <= --spec.precision) {
356        if (buf < end)
357            *buf = '0';
358        ++buf;
359    }
360    /* actual digits of result */
361    while (--i >= 0) {
362        if (buf < end)
363            *buf = tmp[i];
364        ++buf;
365    }
366    /* trailing space padding */
367    while (--spec.field_width >= 0) {
368        if (buf < end)
369            *buf = ' ';
370        ++buf;
371    }
372
373    return buf;
374}
375
376static noinline_for_stack
377char *string(char *buf, char *end, const char *s, struct printf_spec spec)
378{
379    int len, i;
380
381    if ((unsigned long)s < PAGE_SIZE)
382        s = "(null)";
383
384    len = strnlen(s, spec.precision);
385
386    if (!(spec.flags & LEFT)) {
387        while (len < spec.field_width--) {
388            if (buf < end)
389                *buf = ' ';
390            ++buf;
391        }
392    }
393    for (i = 0; i < len; ++i) {
394        if (buf < end)
395            *buf = *s;
396        ++buf; ++s;
397    }
398    while (len < spec.field_width--) {
399        if (buf < end)
400            *buf = ' ';
401        ++buf;
402    }
403
404    return buf;
405}
406
407static noinline_for_stack
408char *symbol_string(char *buf, char *end, void *ptr,
409            struct printf_spec spec, char ext)
410{
411    unsigned long value = (unsigned long) ptr;
412#ifdef CONFIG_KALLSYMS
413    char sym[KSYM_SYMBOL_LEN];
414    if (ext == 'B')
415        sprint_backtrace(sym, value);
416    else if (ext != 'f' && ext != 's')
417        sprint_symbol(sym, value);
418    else
419        kallsyms_lookup(value, NULL, NULL, NULL, sym);
420
421    return string(buf, end, sym, spec);
422#else
423    spec.field_width = 2 * sizeof(void *);
424    spec.flags |= SPECIAL | SMALL | ZEROPAD;
425    spec.base = 16;
426
427    return number(buf, end, value, spec);
428#endif
429}
430
431static noinline_for_stack
432char *resource_string(char *buf, char *end, struct resource *res,
433              struct printf_spec spec, const char *fmt)
434{
435#ifndef IO_RSRC_PRINTK_SIZE
436#define IO_RSRC_PRINTK_SIZE 6
437#endif
438
439#ifndef MEM_RSRC_PRINTK_SIZE
440#define MEM_RSRC_PRINTK_SIZE 10
441#endif
442    static const struct printf_spec io_spec = {
443        .base = 16,
444        .field_width = IO_RSRC_PRINTK_SIZE,
445        .precision = -1,
446        .flags = SPECIAL | SMALL | ZEROPAD,
447    };
448    static const struct printf_spec mem_spec = {
449        .base = 16,
450        .field_width = MEM_RSRC_PRINTK_SIZE,
451        .precision = -1,
452        .flags = SPECIAL | SMALL | ZEROPAD,
453    };
454    static const struct printf_spec bus_spec = {
455        .base = 16,
456        .field_width = 2,
457        .precision = -1,
458        .flags = SMALL | ZEROPAD,
459    };
460    static const struct printf_spec dec_spec = {
461        .base = 10,
462        .precision = -1,
463        .flags = 0,
464    };
465    static const struct printf_spec str_spec = {
466        .field_width = -1,
467        .precision = 10,
468        .flags = LEFT,
469    };
470    static const struct printf_spec flag_spec = {
471        .base = 16,
472        .precision = -1,
473        .flags = SPECIAL | SMALL,
474    };
475
476    /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8)
477     * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */
478#define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4)
479#define FLAG_BUF_SIZE (2 * sizeof(res->flags))
480#define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]")
481#define RAW_BUF_SIZE sizeof("[mem - flags 0x]")
482    char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE,
483             2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)];
484
485    char *p = sym, *pend = sym + sizeof(sym);
486    int decode = (fmt[0] == 'R') ? 1 : 0;
487    const struct printf_spec *specp;
488
489    *p++ = '[';
490    if (res->flags & IORESOURCE_IO) {
491        p = string(p, pend, "io ", str_spec);
492        specp = &io_spec;
493    } else if (res->flags & IORESOURCE_MEM) {
494        p = string(p, pend, "mem ", str_spec);
495        specp = &mem_spec;
496    } else if (res->flags & IORESOURCE_IRQ) {
497        p = string(p, pend, "irq ", str_spec);
498        specp = &dec_spec;
499    } else if (res->flags & IORESOURCE_DMA) {
500        p = string(p, pend, "dma ", str_spec);
501        specp = &dec_spec;
502    } else if (res->flags & IORESOURCE_BUS) {
503        p = string(p, pend, "bus ", str_spec);
504        specp = &bus_spec;
505    } else {
506        p = string(p, pend, "??? ", str_spec);
507        specp = &mem_spec;
508        decode = 0;
509    }
510    p = number(p, pend, res->start, *specp);
511    if (res->start != res->end) {
512        *p++ = '-';
513        p = number(p, pend, res->end, *specp);
514    }
515    if (decode) {
516        if (res->flags & IORESOURCE_MEM_64)
517            p = string(p, pend, " 64bit", str_spec);
518        if (res->flags & IORESOURCE_PREFETCH)
519            p = string(p, pend, " pref", str_spec);
520        if (res->flags & IORESOURCE_WINDOW)
521            p = string(p, pend, " window", str_spec);
522        if (res->flags & IORESOURCE_DISABLED)
523            p = string(p, pend, " disabled", str_spec);
524    } else {
525        p = string(p, pend, " flags ", str_spec);
526        p = number(p, pend, res->flags, flag_spec);
527    }
528    *p++ = ']';
529    *p = '\0';
530
531    return string(buf, end, sym, spec);
532}
533
534static noinline_for_stack
535char *mac_address_string(char *buf, char *end, u8 *addr,
536             struct printf_spec spec, const char *fmt)
537{
538    char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")];
539    char *p = mac_addr;
540    int i;
541    char separator;
542
543    if (fmt[1] == 'F') { /* FDDI canonical format */
544        separator = '-';
545    } else {
546        separator = ':';
547    }
548
549    for (i = 0; i < 6; i++) {
550        p = hex_byte_pack(p, addr[i]);
551        if (fmt[0] == 'M' && i != 5)
552            *p++ = separator;
553    }
554    *p = '\0';
555
556    return string(buf, end, mac_addr, spec);
557}
558
559static noinline_for_stack
560char *ip4_string(char *p, const u8 *addr, const char *fmt)
561{
562    int i;
563    bool leading_zeros = (fmt[0] == 'i');
564    int index;
565    int step;
566
567    switch (fmt[2]) {
568    case 'h':
569#ifdef __BIG_ENDIAN
570        index = 0;
571        step = 1;
572#else
573        index = 3;
574        step = -1;
575#endif
576        break;
577    case 'l':
578        index = 3;
579        step = -1;
580        break;
581    case 'n':
582    case 'b':
583    default:
584        index = 0;
585        step = 1;
586        break;
587    }
588    for (i = 0; i < 4; i++) {
589        char temp[3]; /* hold each IP quad in reverse order */
590        int digits = put_dec_trunc(temp, addr[index]) - temp;
591        if (leading_zeros) {
592            if (digits < 3)
593                *p++ = '0';
594            if (digits < 2)
595                *p++ = '0';
596        }
597        /* reverse the digits in the quad */
598        while (digits--)
599            *p++ = temp[digits];
600        if (i < 3)
601            *p++ = '.';
602        index += step;
603    }
604    *p = '\0';
605
606    return p;
607}
608
609static noinline_for_stack
610char *ip6_compressed_string(char *p, const char *addr)
611{
612    int i, j, range;
613    unsigned char zerolength[8];
614    int longest = 1;
615    int colonpos = -1;
616    u16 word;
617    u8 hi, lo;
618    bool needcolon = false;
619    bool useIPv4;
620    struct in6_addr in6;
621
622    memcpy(&in6, addr, sizeof(struct in6_addr));
623
624    useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6);
625
626    memset(zerolength, 0, sizeof(zerolength));
627
628    if (useIPv4)
629        range = 6;
630    else
631        range = 8;
632
633    /* find position of longest 0 run */
634    for (i = 0; i < range; i++) {
635        for (j = i; j < range; j++) {
636            if (in6.s6_addr16[j] != 0)
637                break;
638            zerolength[i]++;
639        }
640    }
641    for (i = 0; i < range; i++) {
642        if (zerolength[i] > longest) {
643            longest = zerolength[i];
644            colonpos = i;
645        }
646    }
647    if (longest == 1) /* don't compress a single 0 */
648        colonpos = -1;
649
650    /* emit address */
651    for (i = 0; i < range; i++) {
652        if (i == colonpos) {
653            if (needcolon || i == 0)
654                *p++ = ':';
655            *p++ = ':';
656            needcolon = false;
657            i += longest - 1;
658            continue;
659        }
660        if (needcolon) {
661            *p++ = ':';
662            needcolon = false;
663        }
664        /* hex u16 without leading 0s */
665        word = ntohs(in6.s6_addr16[i]);
666        hi = word >> 8;
667        lo = word & 0xff;
668        if (hi) {
669            if (hi > 0x0f)
670                p = hex_byte_pack(p, hi);
671            else
672                *p++ = hex_asc_lo(hi);
673            p = hex_byte_pack(p, lo);
674        }
675        else if (lo > 0x0f)
676            p = hex_byte_pack(p, lo);
677        else
678            *p++ = hex_asc_lo(lo);
679        needcolon = true;
680    }
681
682    if (useIPv4) {
683        if (needcolon)
684            *p++ = ':';
685        p = ip4_string(p, &in6.s6_addr[12], "I4");
686    }
687    *p = '\0';
688
689    return p;
690}
691
692static noinline_for_stack
693char *ip6_string(char *p, const char *addr, const char *fmt)
694{
695    int i;
696
697    for (i = 0; i < 8; i++) {
698        p = hex_byte_pack(p, *addr++);
699        p = hex_byte_pack(p, *addr++);
700        if (fmt[0] == 'I' && i != 7)
701            *p++ = ':';
702    }
703    *p = '\0';
704
705    return p;
706}
707
708static noinline_for_stack
709char *ip6_addr_string(char *buf, char *end, const u8 *addr,
710              struct printf_spec spec, const char *fmt)
711{
712    char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")];
713
714    if (fmt[0] == 'I' && fmt[2] == 'c')
715        ip6_compressed_string(ip6_addr, addr);
716    else
717        ip6_string(ip6_addr, addr, fmt);
718
719    return string(buf, end, ip6_addr, spec);
720}
721
722static noinline_for_stack
723char *ip4_addr_string(char *buf, char *end, const u8 *addr,
724              struct printf_spec spec, const char *fmt)
725{
726    char ip4_addr[sizeof("255.255.255.255")];
727
728    ip4_string(ip4_addr, addr, fmt);
729
730    return string(buf, end, ip4_addr, spec);
731}
732
733static noinline_for_stack
734char *uuid_string(char *buf, char *end, const u8 *addr,
735          struct printf_spec spec, const char *fmt)
736{
737    char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")];
738    char *p = uuid;
739    int i;
740    static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15};
741    static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15};
742    const u8 *index = be;
743    bool uc = false;
744
745    switch (*(++fmt)) {
746    case 'L':
747        uc = true; /* fall-through */
748    case 'l':
749        index = le;
750        break;
751    case 'B':
752        uc = true;
753        break;
754    }
755
756    for (i = 0; i < 16; i++) {
757        p = hex_byte_pack(p, addr[index[i]]);
758        switch (i) {
759        case 3:
760        case 5:
761        case 7:
762        case 9:
763            *p++ = '-';
764            break;
765        }
766    }
767
768    *p = 0;
769
770    if (uc) {
771        p = uuid;
772        do {
773            *p = toupper(*p);
774        } while (*(++p));
775    }
776
777    return string(buf, end, uuid, spec);
778}
779
780static
781char *netdev_feature_string(char *buf, char *end, const u8 *addr,
782              struct printf_spec spec)
783{
784    spec.flags |= SPECIAL | SMALL | ZEROPAD;
785    if (spec.field_width == -1)
786        spec.field_width = 2 + 2 * sizeof(netdev_features_t);
787    spec.base = 16;
788
789    return number(buf, end, *(const netdev_features_t *)addr, spec);
790}
791
792int kptr_restrict __read_mostly;
793
794/*
795 * Show a '%p' thing. A kernel extension is that the '%p' is followed
796 * by an extra set of alphanumeric characters that are extended format
797 * specifiers.
798 *
799 * Right now we handle:
800 *
801 * - 'F' For symbolic function descriptor pointers with offset
802 * - 'f' For simple symbolic function names without offset
803 * - 'S' For symbolic direct pointers with offset
804 * - 's' For symbolic direct pointers without offset
805 * - 'B' For backtraced symbolic direct pointers with offset
806 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref]
807 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201]
808 * - 'M' For a 6-byte MAC address, it prints the address in the
809 * usual colon-separated hex notation
810 * - 'm' For a 6-byte MAC address, it prints the hex address without colons
811 * - 'MF' For a 6-byte MAC FDDI address, it prints the address
812 * with a dash-separated hex notation
813 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way
814 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4)
815 * IPv6 uses colon separated network-order 16 bit hex with leading 0's
816 * - 'i' [46] for 'raw' IPv4/IPv6 addresses
817 * IPv6 omits the colons (01020304...0f)
818 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006)
819 * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order
820 * - 'I6c' for IPv6 addresses printed as specified by
821 * http://tools.ietf.org/html/rfc5952
822 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form
823 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx"
824 * Options for %pU are:
825 * b big endian lower case hex (default)
826 * B big endian UPPER case hex
827 * l little endian lower case hex
828 * L little endian UPPER case hex
829 * big endian output byte order is:
830 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15]
831 * little endian output byte order is:
832 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15]
833 * - 'V' For a struct va_format which contains a format string * and va_list *,
834 * call vsnprintf(->format, *->va_list).
835 * Implements a "recursive vsnprintf".
836 * Do not use this feature without some mechanism to verify the
837 * correctness of the format string and va_list arguments.
838 * - 'K' For a kernel pointer that should be hidden from unprivileged users
839 * - 'NF' For a netdev_features_t
840 *
841 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64
842 * function pointers are really function descriptors, which contain a
843 * pointer to the real address.
844 */
845static noinline_for_stack
846char *pointer(const char *fmt, char *buf, char *end, void *ptr,
847          struct printf_spec spec)
848{
849    if (!ptr && *fmt != 'K') {
850        /*
851         * Print (null) with the same width as a pointer so it makes
852         * tabular output look nice.
853         */
854        if (spec.field_width == -1)
855            spec.field_width = 2 * sizeof(void *);
856        return string(buf, end, "(null)", spec);
857    }
858
859    switch (*fmt) {
860    case 'F':
861    case 'f':
862        ptr = dereference_function_descriptor(ptr);
863        /* Fallthrough */
864    case 'S':
865    case 's':
866    case 'B':
867        return symbol_string(buf, end, ptr, spec, *fmt);
868    case 'R':
869    case 'r':
870        return resource_string(buf, end, ptr, spec, fmt);
871    case 'M': /* Colon separated: 00:01:02:03:04:05 */
872    case 'm': /* Contiguous: 000102030405 */
873                    /* [mM]F (FDDI, bit reversed) */
874        return mac_address_string(buf, end, ptr, spec, fmt);
875    case 'I': /* Formatted IP supported
876                     * 4: 1.2.3.4
877                     * 6: 0001:0203:...:0708
878                     * 6c: 1::708 or 1::1.2.3.4
879                     */
880    case 'i': /* Contiguous:
881                     * 4: 001.002.003.004
882                     * 6: 000102...0f
883                     */
884        switch (fmt[1]) {
885        case '6':
886            return ip6_addr_string(buf, end, ptr, spec, fmt);
887        case '4':
888            return ip4_addr_string(buf, end, ptr, spec, fmt);
889        }
890        break;
891    case 'U':
892        return uuid_string(buf, end, ptr, spec, fmt);
893    case 'V':
894        {
895            va_list va;
896
897            va_copy(va, *((struct va_format *)ptr)->va);
898            buf += vsnprintf(buf, end > buf ? end - buf : 0,
899                     ((struct va_format *)ptr)->fmt, va);
900            va_end(va);
901            return buf;
902        }
903    case 'K':
904        /*
905         * %pK cannot be used in IRQ context because its test
906         * for CAP_SYSLOG would be meaningless.
907         */
908        if (in_irq() || in_serving_softirq() || in_nmi()) {
909            if (spec.field_width == -1)
910                spec.field_width = 2 * sizeof(void *);
911            return string(buf, end, "pK-error", spec);
912        }
913        if (!((kptr_restrict == 0) ||
914              (kptr_restrict == 1 &&
915               has_capability_noaudit(current, CAP_SYSLOG))))
916            ptr = NULL;
917        break;
918    case 'N':
919        switch (fmt[1]) {
920        case 'F':
921            return netdev_feature_string(buf, end, ptr, spec);
922        }
923        break;
924    }
925    spec.flags |= SMALL;
926    if (spec.field_width == -1) {
927        spec.field_width = 2 * sizeof(void *);
928        spec.flags |= ZEROPAD;
929    }
930    spec.base = 16;
931
932    return number(buf, end, (unsigned long) ptr, spec);
933}
934
935/*
936 * Helper function to decode printf style format.
937 * Each call decode a token from the format and return the
938 * number of characters read (or likely the delta where it wants
939 * to go on the next call).
940 * The decoded token is returned through the parameters
941 *
942 * 'h', 'l', or 'L' for integer fields
943 * 'z' support added 23/7/1999 S.H.
944 * 'z' changed to 'Z' --davidm 1/25/99
945 * 't' added for ptrdiff_t
946 *
947 * @fmt: the format string
948 * @type of the token returned
949 * @flags: various flags such as +, -, # tokens..
950 * @field_width: overwritten width
951 * @base: base of the number (octal, hex, ...)
952 * @precision: precision of a number
953 * @qualifier: qualifier of a number (long, size_t, ...)
954 */
955static noinline_for_stack
956int format_decode(const char *fmt, struct printf_spec *spec)
957{
958    const char *start = fmt;
959
960    /* we finished early by reading the field width */
961    if (spec->type == FORMAT_TYPE_WIDTH) {
962        if (spec->field_width < 0) {
963            spec->field_width = -spec->field_width;
964            spec->flags |= LEFT;
965        }
966        spec->type = FORMAT_TYPE_NONE;
967        goto precision;
968    }
969
970    /* we finished early by reading the precision */
971    if (spec->type == FORMAT_TYPE_PRECISION) {
972        if (spec->precision < 0)
973            spec->precision = 0;
974
975        spec->type = FORMAT_TYPE_NONE;
976        goto qualifier;
977    }
978
979    /* By default */
980    spec->type = FORMAT_TYPE_NONE;
981
982    for (; *fmt ; ++fmt) {
983        if (*fmt == '%')
984            break;
985    }
986
987    /* Return the current non-format string */
988    if (fmt != start || !*fmt)
989        return fmt - start;
990
991    /* Process flags */
992    spec->flags = 0;
993
994    while (1) { /* this also skips first '%' */
995        bool found = true;
996
997        ++fmt;
998
999        switch (*fmt) {
1000        case '-': spec->flags |= LEFT; break;
1001        case '+': spec->flags |= PLUS; break;
1002        case ' ': spec->flags |= SPACE; break;
1003        case '#': spec->flags |= SPECIAL; break;
1004        case '0': spec->flags |= ZEROPAD; break;
1005        default: found = false;
1006        }
1007
1008        if (!found)
1009            break;
1010    }
1011
1012    /* get field width */
1013    spec->field_width = -1;
1014
1015    if (isdigit(*fmt))
1016        spec->field_width = skip_atoi(&fmt);
1017    else if (*fmt == '*') {
1018        /* it's the next argument */
1019        spec->type = FORMAT_TYPE_WIDTH;
1020        return ++fmt - start;
1021    }
1022
1023precision:
1024    /* get the precision */
1025    spec->precision = -1;
1026    if (*fmt == '.') {
1027        ++fmt;
1028        if (isdigit(*fmt)) {
1029            spec->precision = skip_atoi(&fmt);
1030            if (spec->precision < 0)
1031                spec->precision = 0;
1032        } else if (*fmt == '*') {
1033            /* it's the next argument */
1034            spec->type = FORMAT_TYPE_PRECISION;
1035            return ++fmt - start;
1036        }
1037    }
1038
1039qualifier:
1040    /* get the conversion qualifier */
1041    spec->qualifier = -1;
1042    if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1043        _tolower(*fmt) == 'z' || *fmt == 't') {
1044        spec->qualifier = *fmt++;
1045        if (unlikely(spec->qualifier == *fmt)) {
1046            if (spec->qualifier == 'l') {
1047                spec->qualifier = 'L';
1048                ++fmt;
1049            } else if (spec->qualifier == 'h') {
1050                spec->qualifier = 'H';
1051                ++fmt;
1052            }
1053        }
1054    }
1055
1056    /* default base */
1057    spec->base = 10;
1058    switch (*fmt) {
1059    case 'c':
1060        spec->type = FORMAT_TYPE_CHAR;
1061        return ++fmt - start;
1062
1063    case 's':
1064        spec->type = FORMAT_TYPE_STR;
1065        return ++fmt - start;
1066
1067    case 'p':
1068        spec->type = FORMAT_TYPE_PTR;
1069        return fmt - start;
1070        /* skip alnum */
1071
1072    case 'n':
1073        spec->type = FORMAT_TYPE_NRCHARS;
1074        return ++fmt - start;
1075
1076    case '%':
1077        spec->type = FORMAT_TYPE_PERCENT_CHAR;
1078        return ++fmt - start;
1079
1080    /* integer number formats - set up the flags and "break" */
1081    case 'o':
1082        spec->base = 8;
1083        break;
1084
1085    case 'x':
1086        spec->flags |= SMALL;
1087
1088    case 'X':
1089        spec->base = 16;
1090        break;
1091
1092    case 'd':
1093    case 'i':
1094        spec->flags |= SIGN;
1095    case 'u':
1096        break;
1097
1098    default:
1099        spec->type = FORMAT_TYPE_INVALID;
1100        return fmt - start;
1101    }
1102
1103    if (spec->qualifier == 'L')
1104        spec->type = FORMAT_TYPE_LONG_LONG;
1105    else if (spec->qualifier == 'l') {
1106        if (spec->flags & SIGN)
1107            spec->type = FORMAT_TYPE_LONG;
1108        else
1109            spec->type = FORMAT_TYPE_ULONG;
1110    } else if (_tolower(spec->qualifier) == 'z') {
1111        spec->type = FORMAT_TYPE_SIZE_T;
1112    } else if (spec->qualifier == 't') {
1113        spec->type = FORMAT_TYPE_PTRDIFF;
1114    } else if (spec->qualifier == 'H') {
1115        if (spec->flags & SIGN)
1116            spec->type = FORMAT_TYPE_BYTE;
1117        else
1118            spec->type = FORMAT_TYPE_UBYTE;
1119    } else if (spec->qualifier == 'h') {
1120        if (spec->flags & SIGN)
1121            spec->type = FORMAT_TYPE_SHORT;
1122        else
1123            spec->type = FORMAT_TYPE_USHORT;
1124    } else {
1125        if (spec->flags & SIGN)
1126            spec->type = FORMAT_TYPE_INT;
1127        else
1128            spec->type = FORMAT_TYPE_UINT;
1129    }
1130
1131    return ++fmt - start;
1132}
1133
1134/**
1135 * vsnprintf - Format a string and place it in a buffer
1136 * @buf: The buffer to place the result into
1137 * @size: The size of the buffer, including the trailing null space
1138 * @fmt: The format string to use
1139 * @args: Arguments for the format string
1140 *
1141 * This function follows C99 vsnprintf, but has some extensions:
1142 * %pS output the name of a text symbol with offset
1143 * %ps output the name of a text symbol without offset
1144 * %pF output the name of a function pointer with its offset
1145 * %pf output the name of a function pointer without its offset
1146 * %pB output the name of a backtrace symbol with its offset
1147 * %pR output the address range in a struct resource with decoded flags
1148 * %pr output the address range in a struct resource with raw flags
1149 * %pM output a 6-byte MAC address with colons
1150 * %pm output a 6-byte MAC address without colons
1151 * %pI4 print an IPv4 address without leading zeros
1152 * %pi4 print an IPv4 address with leading zeros
1153 * %pI6 print an IPv6 address with colons
1154 * %pi6 print an IPv6 address without colons
1155 * %pI6c print an IPv6 address as specified by RFC 5952
1156 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper
1157 * case.
1158 * %n is ignored
1159 *
1160 * The return value is the number of characters which would
1161 * be generated for the given input, excluding the trailing
1162 * '\0', as per ISO C99. If you want to have the exact
1163 * number of characters written into @buf as return value
1164 * (not including the trailing '\0'), use vscnprintf(). If the
1165 * return is greater than or equal to @size, the resulting
1166 * string is truncated.
1167 *
1168 * If you're not already dealing with a va_list consider using snprintf().
1169 */
1170int vsnprintf(char *buf, size_t size, const char *fmt, va_list args)
1171{
1172    unsigned long long num;
1173    char *str, *end;
1174    struct printf_spec spec = {0};
1175
1176    /* Reject out-of-range values early. Large positive sizes are
1177       used for unknown buffer sizes. */
1178    if (WARN_ON_ONCE((int) size < 0))
1179        return 0;
1180
1181    str = buf;
1182    end = buf + size;
1183
1184    /* Make sure end is always >= buf */
1185    if (end < buf) {
1186        end = ((void *)-1);
1187        size = end - buf;
1188    }
1189
1190    while (*fmt) {
1191        const char *old_fmt = fmt;
1192        int read = format_decode(fmt, &spec);
1193
1194        fmt += read;
1195
1196        switch (spec.type) {
1197        case FORMAT_TYPE_NONE: {
1198            int copy = read;
1199            if (str < end) {
1200                if (copy > end - str)
1201                    copy = end - str;
1202                memcpy(str, old_fmt, copy);
1203            }
1204            str += read;
1205            break;
1206        }
1207
1208        case FORMAT_TYPE_WIDTH:
1209            spec.field_width = va_arg(args, int);
1210            break;
1211
1212        case FORMAT_TYPE_PRECISION:
1213            spec.precision = va_arg(args, int);
1214            break;
1215
1216        case FORMAT_TYPE_CHAR: {
1217            char c;
1218
1219            if (!(spec.flags & LEFT)) {
1220                while (--spec.field_width > 0) {
1221                    if (str < end)
1222                        *str = ' ';
1223                    ++str;
1224
1225                }
1226            }
1227            c = (unsigned char) va_arg(args, int);
1228            if (str < end)
1229                *str = c;
1230            ++str;
1231            while (--spec.field_width > 0) {
1232                if (str < end)
1233                    *str = ' ';
1234                ++str;
1235            }
1236            break;
1237        }
1238
1239        case FORMAT_TYPE_STR:
1240            str = string(str, end, va_arg(args, char *), spec);
1241            break;
1242
1243        case FORMAT_TYPE_PTR:
1244            str = pointer(fmt+1, str, end, va_arg(args, void *),
1245                      spec);
1246            while (isalnum(*fmt))
1247                fmt++;
1248            break;
1249
1250        case FORMAT_TYPE_PERCENT_CHAR:
1251            if (str < end)
1252                *str = '%';
1253            ++str;
1254            break;
1255
1256        case FORMAT_TYPE_INVALID:
1257            if (str < end)
1258                *str = '%';
1259            ++str;
1260            break;
1261
1262        case FORMAT_TYPE_NRCHARS: {
1263            u8 qualifier = spec.qualifier;
1264
1265            if (qualifier == 'l') {
1266                long *ip = va_arg(args, long *);
1267                *ip = (str - buf);
1268            } else if (_tolower(qualifier) == 'z') {
1269                size_t *ip = va_arg(args, size_t *);
1270                *ip = (str - buf);
1271            } else {
1272                int *ip = va_arg(args, int *);
1273                *ip = (str - buf);
1274            }
1275            break;
1276        }
1277
1278        default:
1279            switch (spec.type) {
1280            case FORMAT_TYPE_LONG_LONG:
1281                num = va_arg(args, long long);
1282                break;
1283            case FORMAT_TYPE_ULONG:
1284                num = va_arg(args, unsigned long);
1285                break;
1286            case FORMAT_TYPE_LONG:
1287                num = va_arg(args, long);
1288                break;
1289            case FORMAT_TYPE_SIZE_T:
1290                num = va_arg(args, size_t);
1291                break;
1292            case FORMAT_TYPE_PTRDIFF:
1293                num = va_arg(args, ptrdiff_t);
1294                break;
1295            case FORMAT_TYPE_UBYTE:
1296                num = (unsigned char) va_arg(args, int);
1297                break;
1298            case FORMAT_TYPE_BYTE:
1299                num = (signed char) va_arg(args, int);
1300                break;
1301            case FORMAT_TYPE_USHORT:
1302                num = (unsigned short) va_arg(args, int);
1303                break;
1304            case FORMAT_TYPE_SHORT:
1305                num = (short) va_arg(args, int);
1306                break;
1307            case FORMAT_TYPE_INT:
1308                num = (int) va_arg(args, int);
1309                break;
1310            default:
1311                num = va_arg(args, unsigned int);
1312            }
1313
1314            str = number(str, end, num, spec);
1315        }
1316    }
1317
1318    if (size > 0) {
1319        if (str < end)
1320            *str = '\0';
1321        else
1322            end[-1] = '\0';
1323    }
1324
1325    /* the trailing null byte doesn't count towards the total */
1326    return str-buf;
1327
1328}
1329EXPORT_SYMBOL(vsnprintf);
1330
1331/**
1332 * vscnprintf - Format a string and place it in a buffer
1333 * @buf: The buffer to place the result into
1334 * @size: The size of the buffer, including the trailing null space
1335 * @fmt: The format string to use
1336 * @args: Arguments for the format string
1337 *
1338 * The return value is the number of characters which have been written into
1339 * the @buf not including the trailing '\0'. If @size is == 0 the function
1340 * returns 0.
1341 *
1342 * If you're not already dealing with a va_list consider using scnprintf().
1343 *
1344 * See the vsnprintf() documentation for format string extensions over C99.
1345 */
1346int vscnprintf(char *buf, size_t size, const char *fmt, va_list args)
1347{
1348    int i;
1349
1350    i = vsnprintf(buf, size, fmt, args);
1351
1352    if (likely(i < size))
1353        return i;
1354    if (size != 0)
1355        return size - 1;
1356    return 0;
1357}
1358EXPORT_SYMBOL(vscnprintf);
1359
1360/**
1361 * snprintf - Format a string and place it in a buffer
1362 * @buf: The buffer to place the result into
1363 * @size: The size of the buffer, including the trailing null space
1364 * @fmt: The format string to use
1365 * @...: Arguments for the format string
1366 *
1367 * The return value is the number of characters which would be
1368 * generated for the given input, excluding the trailing null,
1369 * as per ISO C99. If the return is greater than or equal to
1370 * @size, the resulting string is truncated.
1371 *
1372 * See the vsnprintf() documentation for format string extensions over C99.
1373 */
1374int snprintf(char *buf, size_t size, const char *fmt, ...)
1375{
1376    va_list args;
1377    int i;
1378
1379    va_start(args, fmt);
1380    i = vsnprintf(buf, size, fmt, args);
1381    va_end(args);
1382
1383    return i;
1384}
1385EXPORT_SYMBOL(snprintf);
1386
1387/**
1388 * scnprintf - Format a string and place it in a buffer
1389 * @buf: The buffer to place the result into
1390 * @size: The size of the buffer, including the trailing null space
1391 * @fmt: The format string to use
1392 * @...: Arguments for the format string
1393 *
1394 * The return value is the number of characters written into @buf not including
1395 * the trailing '\0'. If @size is == 0 the function returns 0.
1396 */
1397
1398int scnprintf(char *buf, size_t size, const char *fmt, ...)
1399{
1400    va_list args;
1401    int i;
1402
1403    va_start(args, fmt);
1404    i = vscnprintf(buf, size, fmt, args);
1405    va_end(args);
1406
1407    return i;
1408}
1409EXPORT_SYMBOL(scnprintf);
1410
1411/**
1412 * vsprintf - Format a string and place it in a buffer
1413 * @buf: The buffer to place the result into
1414 * @fmt: The format string to use
1415 * @args: Arguments for the format string
1416 *
1417 * The function returns the number of characters written
1418 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid
1419 * buffer overflows.
1420 *
1421 * If you're not already dealing with a va_list consider using sprintf().
1422 *
1423 * See the vsnprintf() documentation for format string extensions over C99.
1424 */
1425int vsprintf(char *buf, const char *fmt, va_list args)
1426{
1427    return vsnprintf(buf, INT_MAX, fmt, args);
1428}
1429EXPORT_SYMBOL(vsprintf);
1430
1431/**
1432 * sprintf - Format a string and place it in a buffer
1433 * @buf: The buffer to place the result into
1434 * @fmt: The format string to use
1435 * @...: Arguments for the format string
1436 *
1437 * The function returns the number of characters written
1438 * into @buf. Use snprintf() or scnprintf() in order to avoid
1439 * buffer overflows.
1440 *
1441 * See the vsnprintf() documentation for format string extensions over C99.
1442 */
1443int sprintf(char *buf, const char *fmt, ...)
1444{
1445    va_list args;
1446    int i;
1447
1448    va_start(args, fmt);
1449    i = vsnprintf(buf, INT_MAX, fmt, args);
1450    va_end(args);
1451
1452    return i;
1453}
1454EXPORT_SYMBOL(sprintf);
1455
1456#ifdef CONFIG_BINARY_PRINTF
1457/*
1458 * bprintf service:
1459 * vbin_printf() - VA arguments to binary data
1460 * bstr_printf() - Binary data to text string
1461 */
1462
1463/**
1464 * vbin_printf - Parse a format string and place args' binary value in a buffer
1465 * @bin_buf: The buffer to place args' binary value
1466 * @size: The size of the buffer(by words(32bits), not characters)
1467 * @fmt: The format string to use
1468 * @args: Arguments for the format string
1469 *
1470 * The format follows C99 vsnprintf, except %n is ignored, and its argument
1471 * is skiped.
1472 *
1473 * The return value is the number of words(32bits) which would be generated for
1474 * the given input.
1475 *
1476 * NOTE:
1477 * If the return value is greater than @size, the resulting bin_buf is NOT
1478 * valid for bstr_printf().
1479 */
1480int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args)
1481{
1482    struct printf_spec spec = {0};
1483    char *str, *end;
1484
1485    str = (char *)bin_buf;
1486    end = (char *)(bin_buf + size);
1487
1488#define save_arg(type) \
1489do { \
1490    if (sizeof(type) == 8) { \
1491        unsigned long long value; \
1492        str = PTR_ALIGN(str, sizeof(u32)); \
1493        value = va_arg(args, unsigned long long); \
1494        if (str + sizeof(type) <= end) { \
1495            *(u32 *)str = *(u32 *)&value; \
1496            *(u32 *)(str + 4) = *((u32 *)&value + 1); \
1497        } \
1498    } else { \
1499        unsigned long value; \
1500        str = PTR_ALIGN(str, sizeof(type)); \
1501        value = va_arg(args, int); \
1502        if (str + sizeof(type) <= end) \
1503            *(typeof(type) *)str = (type)value; \
1504    } \
1505    str += sizeof(type); \
1506} while (0)
1507
1508    while (*fmt) {
1509        int read = format_decode(fmt, &spec);
1510
1511        fmt += read;
1512
1513        switch (spec.type) {
1514        case FORMAT_TYPE_NONE:
1515        case FORMAT_TYPE_INVALID:
1516        case FORMAT_TYPE_PERCENT_CHAR:
1517            break;
1518
1519        case FORMAT_TYPE_WIDTH:
1520        case FORMAT_TYPE_PRECISION:
1521            save_arg(int);
1522            break;
1523
1524        case FORMAT_TYPE_CHAR:
1525            save_arg(char);
1526            break;
1527
1528        case FORMAT_TYPE_STR: {
1529            const char *save_str = va_arg(args, char *);
1530            size_t len;
1531
1532            if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE
1533                    || (unsigned long)save_str < PAGE_SIZE)
1534                save_str = "(null)";
1535            len = strlen(save_str) + 1;
1536            if (str + len < end)
1537                memcpy(str, save_str, len);
1538            str += len;
1539            break;
1540        }
1541
1542        case FORMAT_TYPE_PTR:
1543            save_arg(void *);
1544            /* skip all alphanumeric pointer suffixes */
1545            while (isalnum(*fmt))
1546                fmt++;
1547            break;
1548
1549        case FORMAT_TYPE_NRCHARS: {
1550            /* skip %n 's argument */
1551            u8 qualifier = spec.qualifier;
1552            void *skip_arg;
1553            if (qualifier == 'l')
1554                skip_arg = va_arg(args, long *);
1555            else if (_tolower(qualifier) == 'z')
1556                skip_arg = va_arg(args, size_t *);
1557            else
1558                skip_arg = va_arg(args, int *);
1559            break;
1560        }
1561
1562        default:
1563            switch (spec.type) {
1564
1565            case FORMAT_TYPE_LONG_LONG:
1566                save_arg(long long);
1567                break;
1568            case FORMAT_TYPE_ULONG:
1569            case FORMAT_TYPE_LONG:
1570                save_arg(unsigned long);
1571                break;
1572            case FORMAT_TYPE_SIZE_T:
1573                save_arg(size_t);
1574                break;
1575            case FORMAT_TYPE_PTRDIFF:
1576                save_arg(ptrdiff_t);
1577                break;
1578            case FORMAT_TYPE_UBYTE:
1579            case FORMAT_TYPE_BYTE:
1580                save_arg(char);
1581                break;
1582            case FORMAT_TYPE_USHORT:
1583            case FORMAT_TYPE_SHORT:
1584                save_arg(short);
1585                break;
1586            default:
1587                save_arg(int);
1588            }
1589        }
1590    }
1591
1592    return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf;
1593#undef save_arg
1594}
1595EXPORT_SYMBOL_GPL(vbin_printf);
1596
1597/**
1598 * bstr_printf - Format a string from binary arguments and place it in a buffer
1599 * @buf: The buffer to place the result into
1600 * @size: The size of the buffer, including the trailing null space
1601 * @fmt: The format string to use
1602 * @bin_buf: Binary arguments for the format string
1603 *
1604 * This function like C99 vsnprintf, but the difference is that vsnprintf gets
1605 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is
1606 * a binary buffer that generated by vbin_printf.
1607 *
1608 * The format follows C99 vsnprintf, but has some extensions:
1609 * see vsnprintf comment for details.
1610 *
1611 * The return value is the number of characters which would
1612 * be generated for the given input, excluding the trailing
1613 * '\0', as per ISO C99. If you want to have the exact
1614 * number of characters written into @buf as return value
1615 * (not including the trailing '\0'), use vscnprintf(). If the
1616 * return is greater than or equal to @size, the resulting
1617 * string is truncated.
1618 */
1619int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf)
1620{
1621    struct printf_spec spec = {0};
1622    char *str, *end;
1623    const char *args = (const char *)bin_buf;
1624
1625    if (WARN_ON_ONCE((int) size < 0))
1626        return 0;
1627
1628    str = buf;
1629    end = buf + size;
1630
1631#define get_arg(type) \
1632({ \
1633    typeof(type) value; \
1634    if (sizeof(type) == 8) { \
1635        args = PTR_ALIGN(args, sizeof(u32)); \
1636        *(u32 *)&value = *(u32 *)args; \
1637        *((u32 *)&value + 1) = *(u32 *)(args + 4); \
1638    } else { \
1639        args = PTR_ALIGN(args, sizeof(type)); \
1640        value = *(typeof(type) *)args; \
1641    } \
1642    args += sizeof(type); \
1643    value; \
1644})
1645
1646    /* Make sure end is always >= buf */
1647    if (end < buf) {
1648        end = ((void *)-1);
1649        size = end - buf;
1650    }
1651
1652    while (*fmt) {
1653        const char *old_fmt = fmt;
1654        int read = format_decode(fmt, &spec);
1655
1656        fmt += read;
1657
1658        switch (spec.type) {
1659        case FORMAT_TYPE_NONE: {
1660            int copy = read;
1661            if (str < end) {
1662                if (copy > end - str)
1663                    copy = end - str;
1664                memcpy(str, old_fmt, copy);
1665            }
1666            str += read;
1667            break;
1668        }
1669
1670        case FORMAT_TYPE_WIDTH:
1671            spec.field_width = get_arg(int);
1672            break;
1673
1674        case FORMAT_TYPE_PRECISION:
1675            spec.precision = get_arg(int);
1676            break;
1677
1678        case FORMAT_TYPE_CHAR: {
1679            char c;
1680
1681            if (!(spec.flags & LEFT)) {
1682                while (--spec.field_width > 0) {
1683                    if (str < end)
1684                        *str = ' ';
1685                    ++str;
1686                }
1687            }
1688            c = (unsigned char) get_arg(char);
1689            if (str < end)
1690                *str = c;
1691            ++str;
1692            while (--spec.field_width > 0) {
1693                if (str < end)
1694                    *str = ' ';
1695                ++str;
1696            }
1697            break;
1698        }
1699
1700        case FORMAT_TYPE_STR: {
1701            const char *str_arg = args;
1702            args += strlen(str_arg) + 1;
1703            str = string(str, end, (char *)str_arg, spec);
1704            break;
1705        }
1706
1707        case FORMAT_TYPE_PTR:
1708            str = pointer(fmt+1, str, end, get_arg(void *), spec);
1709            while (isalnum(*fmt))
1710                fmt++;
1711            break;
1712
1713        case FORMAT_TYPE_PERCENT_CHAR:
1714        case FORMAT_TYPE_INVALID:
1715            if (str < end)
1716                *str = '%';
1717            ++str;
1718            break;
1719
1720        case FORMAT_TYPE_NRCHARS:
1721            /* skip */
1722            break;
1723
1724        default: {
1725            unsigned long long num;
1726
1727            switch (spec.type) {
1728
1729            case FORMAT_TYPE_LONG_LONG:
1730                num = get_arg(long long);
1731                break;
1732            case FORMAT_TYPE_ULONG:
1733            case FORMAT_TYPE_LONG:
1734                num = get_arg(unsigned long);
1735                break;
1736            case FORMAT_TYPE_SIZE_T:
1737                num = get_arg(size_t);
1738                break;
1739            case FORMAT_TYPE_PTRDIFF:
1740                num = get_arg(ptrdiff_t);
1741                break;
1742            case FORMAT_TYPE_UBYTE:
1743                num = get_arg(unsigned char);
1744                break;
1745            case FORMAT_TYPE_BYTE:
1746                num = get_arg(signed char);
1747                break;
1748            case FORMAT_TYPE_USHORT:
1749                num = get_arg(unsigned short);
1750                break;
1751            case FORMAT_TYPE_SHORT:
1752                num = get_arg(short);
1753                break;
1754            case FORMAT_TYPE_UINT:
1755                num = get_arg(unsigned int);
1756                break;
1757            default:
1758                num = get_arg(int);
1759            }
1760
1761            str = number(str, end, num, spec);
1762        } /* default: */
1763        } /* switch(spec.type) */
1764    } /* while(*fmt) */
1765
1766    if (size > 0) {
1767        if (str < end)
1768            *str = '\0';
1769        else
1770            end[-1] = '\0';
1771    }
1772
1773#undef get_arg
1774
1775    /* the trailing null byte doesn't count towards the total */
1776    return str - buf;
1777}
1778EXPORT_SYMBOL_GPL(bstr_printf);
1779
1780/**
1781 * bprintf - Parse a format string and place args' binary value in a buffer
1782 * @bin_buf: The buffer to place args' binary value
1783 * @size: The size of the buffer(by words(32bits), not characters)
1784 * @fmt: The format string to use
1785 * @...: Arguments for the format string
1786 *
1787 * The function returns the number of words(u32) written
1788 * into @bin_buf.
1789 */
1790int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...)
1791{
1792    va_list args;
1793    int ret;
1794
1795    va_start(args, fmt);
1796    ret = vbin_printf(bin_buf, size, fmt, args);
1797    va_end(args);
1798
1799    return ret;
1800}
1801EXPORT_SYMBOL_GPL(bprintf);
1802
1803#endif /* CONFIG_BINARY_PRINTF */
1804
1805/**
1806 * vsscanf - Unformat a buffer into a list of arguments
1807 * @buf: input buffer
1808 * @fmt: format of buffer
1809 * @args: arguments
1810 */
1811int vsscanf(const char *buf, const char *fmt, va_list args)
1812{
1813    const char *str = buf;
1814    char *next;
1815    char digit;
1816    int num = 0;
1817    u8 qualifier;
1818    u8 base;
1819    s16 field_width;
1820    bool is_sign;
1821
1822    while (*fmt && *str) {
1823        /* skip any white space in format */
1824        /* white space in format matchs any amount of
1825         * white space, including none, in the input.
1826         */
1827        if (isspace(*fmt)) {
1828            fmt = skip_spaces(++fmt);
1829            str = skip_spaces(str);
1830        }
1831
1832        /* anything that is not a conversion must match exactly */
1833        if (*fmt != '%' && *fmt) {
1834            if (*fmt++ != *str++)
1835                break;
1836            continue;
1837        }
1838
1839        if (!*fmt)
1840            break;
1841        ++fmt;
1842
1843        /* skip this conversion.
1844         * advance both strings to next white space
1845         */
1846        if (*fmt == '*') {
1847            while (!isspace(*fmt) && *fmt != '%' && *fmt)
1848                fmt++;
1849            while (!isspace(*str) && *str)
1850                str++;
1851            continue;
1852        }
1853
1854        /* get field width */
1855        field_width = -1;
1856        if (isdigit(*fmt))
1857            field_width = skip_atoi(&fmt);
1858
1859        /* get conversion qualifier */
1860        qualifier = -1;
1861        if (*fmt == 'h' || _tolower(*fmt) == 'l' ||
1862            _tolower(*fmt) == 'z') {
1863            qualifier = *fmt++;
1864            if (unlikely(qualifier == *fmt)) {
1865                if (qualifier == 'h') {
1866                    qualifier = 'H';
1867                    fmt++;
1868                } else if (qualifier == 'l') {
1869                    qualifier = 'L';
1870                    fmt++;
1871                }
1872            }
1873        }
1874
1875        if (!*fmt || !*str)
1876            break;
1877
1878        base = 10;
1879        is_sign = 0;
1880
1881        switch (*fmt++) {
1882        case 'c':
1883        {
1884            char *s = (char *)va_arg(args, char*);
1885            if (field_width == -1)
1886                field_width = 1;
1887            do {
1888                *s++ = *str++;
1889            } while (--field_width > 0 && *str);
1890            num++;
1891        }
1892        continue;
1893        case 's':
1894        {
1895            char *s = (char *)va_arg(args, char *);
1896            if (field_width == -1)
1897                field_width = SHRT_MAX;
1898            /* first, skip leading white space in buffer */
1899            str = skip_spaces(str);
1900
1901            /* now copy until next white space */
1902            while (*str && !isspace(*str) && field_width--)
1903                *s++ = *str++;
1904            *s = '\0';
1905            num++;
1906        }
1907        continue;
1908        case 'n':
1909            /* return number of characters read so far */
1910        {
1911            int *i = (int *)va_arg(args, int*);
1912            *i = str - buf;
1913        }
1914        continue;
1915        case 'o':
1916            base = 8;
1917            break;
1918        case 'x':
1919        case 'X':
1920            base = 16;
1921            break;
1922        case 'i':
1923            base = 0;
1924        case 'd':
1925            is_sign = 1;
1926        case 'u':
1927            break;
1928        case '%':
1929            /* looking for '%' in str */
1930            if (*str++ != '%')
1931                return num;
1932            continue;
1933        default:
1934            /* invalid format; stop here */
1935            return num;
1936        }
1937
1938        /* have some sort of integer conversion.
1939         * first, skip white space in buffer.
1940         */
1941        str = skip_spaces(str);
1942
1943        digit = *str;
1944        if (is_sign && digit == '-')
1945            digit = *(str + 1);
1946
1947        if (!digit
1948            || (base == 16 && !isxdigit(digit))
1949            || (base == 10 && !isdigit(digit))
1950            || (base == 8 && (!isdigit(digit) || digit > '7'))
1951            || (base == 0 && !isdigit(digit)))
1952            break;
1953
1954        switch (qualifier) {
1955        case 'H': /* that's 'hh' in format */
1956            if (is_sign) {
1957                signed char *s = (signed char *)va_arg(args, signed char *);
1958                *s = (signed char)simple_strtol(str, &next, base);
1959            } else {
1960                unsigned char *s = (unsigned char *)va_arg(args, unsigned char *);
1961                *s = (unsigned char)simple_strtoul(str, &next, base);
1962            }
1963            break;
1964        case 'h':
1965            if (is_sign) {
1966                short *s = (short *)va_arg(args, short *);
1967                *s = (short)simple_strtol(str, &next, base);
1968            } else {
1969                unsigned short *s = (unsigned short *)va_arg(args, unsigned short *);
1970                *s = (unsigned short)simple_strtoul(str, &next, base);
1971            }
1972            break;
1973        case 'l':
1974            if (is_sign) {
1975                long *l = (long *)va_arg(args, long *);
1976                *l = simple_strtol(str, &next, base);
1977            } else {
1978                unsigned long *l = (unsigned long *)va_arg(args, unsigned long *);
1979                *l = simple_strtoul(str, &next, base);
1980            }
1981            break;
1982        case 'L':
1983            if (is_sign) {
1984                long long *l = (long long *)va_arg(args, long long *);
1985                *l = simple_strtoll(str, &next, base);
1986            } else {
1987                unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *);
1988                *l = simple_strtoull(str, &next, base);
1989            }
1990            break;
1991        case 'Z':
1992        case 'z':
1993        {
1994            size_t *s = (size_t *)va_arg(args, size_t *);
1995            *s = (size_t)simple_strtoul(str, &next, base);
1996        }
1997        break;
1998        default:
1999            if (is_sign) {
2000                int *i = (int *)va_arg(args, int *);
2001                *i = (int)simple_strtol(str, &next, base);
2002            } else {
2003                unsigned int *i = (unsigned int *)va_arg(args, unsigned int*);
2004                *i = (unsigned int)simple_strtoul(str, &next, base);
2005            }
2006            break;
2007        }
2008        num++;
2009
2010        if (!next)
2011            break;
2012        str = next;
2013    }
2014
2015    /*
2016     * Now we've come all the way through so either the input string or the
2017     * format ended. In the former case, there can be a %n at the current
2018     * position in the format that needs to be filled.
2019     */
2020    if (*fmt == '%' && *(fmt + 1) == 'n') {
2021        int *p = (int *)va_arg(args, int *);
2022        *p = str - buf;
2023    }
2024
2025    return num;
2026}
2027EXPORT_SYMBOL(vsscanf);
2028
2029/**
2030 * sscanf - Unformat a buffer into a list of arguments
2031 * @buf: input buffer
2032 * @fmt: formatting of buffer
2033 * @...: resulting arguments
2034 */
2035int sscanf(const char *buf, const char *fmt, ...)
2036{
2037    va_list args;
2038    int i;
2039
2040    va_start(args, fmt);
2041    i = vsscanf(buf, fmt, args);
2042    va_end(args);
2043
2044    return i;
2045}
2046EXPORT_SYMBOL(sscanf);
2047

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