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/* Works only for digits and letters, but small and fast */ 35#define TOLOWER(x) ((x) | 0x20) 36 37static unsigned int simple_guess_base(const char *cp) 38{ 39 if (cp[0] == '0') { 40 if (TOLOWER(cp[1]) == 'x' && isxdigit(cp[2])) 41 return 16; 42 else 43 return 8; 44 } else { 45 return 10; 46 } 47} 48 49/** 50 * simple_strtoull - convert a string to an unsigned long long 51 * @cp: The start of the string 52 * @endp: A pointer to the end of the parsed string will be placed here 53 * @base: The number base to use 54 */ 55unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) 56{ 57 unsigned long long result = 0; 58 59 if (!base) 60 base = simple_guess_base(cp); 61 62 if (base == 16 && cp[0] == '0' && TOLOWER(cp[1]) == 'x') 63 cp += 2; 64 65 while (isxdigit(*cp)) { 66 unsigned int value; 67 68 value = isdigit(*cp) ? *cp - '0' : TOLOWER(*cp) - 'a' + 10; 69 if (value >= base) 70 break; 71 result = result * base + value; 72 cp++; 73 } 74 if (endp) 75 *endp = (char *)cp; 76 77 return result; 78} 79EXPORT_SYMBOL(simple_strtoull); 80 81/** 82 * simple_strtoul - convert a string to an unsigned long 83 * @cp: The start of the string 84 * @endp: A pointer to the end of the parsed string will be placed here 85 * @base: The number base to use 86 */ 87unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) 88{ 89 return simple_strtoull(cp, endp, base); 90} 91EXPORT_SYMBOL(simple_strtoul); 92 93/** 94 * simple_strtol - convert a string to a signed long 95 * @cp: The start of the string 96 * @endp: A pointer to the end of the parsed string will be placed here 97 * @base: The number base to use 98 */ 99long simple_strtol(const char *cp, char **endp, unsigned int base) 100{ 101 if (*cp == '-') 102 return -simple_strtoul(cp + 1, endp, base); 103 104 return simple_strtoul(cp, endp, base); 105} 106EXPORT_SYMBOL(simple_strtol); 107 108/** 109 * simple_strtoll - convert a string to a signed long long 110 * @cp: The start of the string 111 * @endp: A pointer to the end of the parsed string will be placed here 112 * @base: The number base to use 113 */ 114long long simple_strtoll(const char *cp, char **endp, unsigned int base) 115{ 116 if (*cp == '-') 117 return -simple_strtoull(cp + 1, endp, base); 118 119 return simple_strtoull(cp, endp, base); 120} 121EXPORT_SYMBOL(simple_strtoll); 122 123/** 124 * strict_strtoul - convert a string to an unsigned long strictly 125 * @cp: The string to be converted 126 * @base: The number base to use 127 * @res: The converted result value 128 * 129 * strict_strtoul converts a string to an unsigned long only if the 130 * string is really an unsigned long string, any string containing 131 * any invalid char at the tail will be rejected and -EINVAL is returned, 132 * only a newline char at the tail is acceptible because people generally 133 * change a module parameter in the following way: 134 * 135 * echo 1024 > /sys/module/e1000/parameters/copybreak 136 * 137 * echo will append a newline to the tail. 138 * 139 * It returns 0 if conversion is successful and *res is set to the converted 140 * value, otherwise it returns -EINVAL and *res is set to 0. 141 * 142 * simple_strtoul just ignores the successive invalid characters and 143 * return the converted value of prefix part of the string. 144 */ 145int strict_strtoul(const char *cp, unsigned int base, unsigned long *res) 146{ 147 char *tail; 148 unsigned long val; 149 150 *res = 0; 151 if (!*cp) 152 return -EINVAL; 153 154 val = simple_strtoul(cp, &tail, base); 155 if (tail == cp) 156 return -EINVAL; 157 158 if ((tail[0] == '\0') || (tail[0] == '\n' && tail[1] == '\0')) { 159 *res = val; 160 return 0; 161 } 162 163 return -EINVAL; 164} 165EXPORT_SYMBOL(strict_strtoul); 166 167/** 168 * strict_strtol - convert a string to a long strictly 169 * @cp: The string to be converted 170 * @base: The number base to use 171 * @res: The converted result value 172 * 173 * strict_strtol is similiar to strict_strtoul, but it allows the first 174 * character of a string is '-'. 175 * 176 * It returns 0 if conversion is successful and *res is set to the converted 177 * value, otherwise it returns -EINVAL and *res is set to 0. 178 */ 179int strict_strtol(const char *cp, unsigned int base, long *res) 180{ 181 int ret; 182 if (*cp == '-') { 183 ret = strict_strtoul(cp + 1, base, (unsigned long *)res); 184 if (!ret) 185 *res = -(*res); 186 } else { 187 ret = strict_strtoul(cp, base, (unsigned long *)res); 188 } 189 190 return ret; 191} 192EXPORT_SYMBOL(strict_strtol); 193 194/** 195 * strict_strtoull - convert a string to an unsigned long long strictly 196 * @cp: The string to be converted 197 * @base: The number base to use 198 * @res: The converted result value 199 * 200 * strict_strtoull converts a string to an unsigned long long only if the 201 * string is really an unsigned long long string, any string containing 202 * any invalid char at the tail will be rejected and -EINVAL is returned, 203 * only a newline char at the tail is acceptible because people generally 204 * change a module parameter in the following way: 205 * 206 * echo 1024 > /sys/module/e1000/parameters/copybreak 207 * 208 * echo will append a newline to the tail of the string. 209 * 210 * It returns 0 if conversion is successful and *res is set to the converted 211 * value, otherwise it returns -EINVAL and *res is set to 0. 212 * 213 * simple_strtoull just ignores the successive invalid characters and 214 * return the converted value of prefix part of the string. 215 */ 216int strict_strtoull(const char *cp, unsigned int base, unsigned long long *res) 217{ 218 char *tail; 219 unsigned long long val; 220 221 *res = 0; 222 if (!*cp) 223 return -EINVAL; 224 225 val = simple_strtoull(cp, &tail, base); 226 if (tail == cp) 227 return -EINVAL; 228 if ((tail[0] == '\0') || (tail[0] == '\n' && tail[1] == '\0')) { 229 *res = val; 230 return 0; 231 } 232 233 return -EINVAL; 234} 235EXPORT_SYMBOL(strict_strtoull); 236 237/** 238 * strict_strtoll - convert a string to a long long strictly 239 * @cp: The string to be converted 240 * @base: The number base to use 241 * @res: The converted result value 242 * 243 * strict_strtoll is similiar to strict_strtoull, but it allows the first 244 * character of a string is '-'. 245 * 246 * It returns 0 if conversion is successful and *res is set to the converted 247 * value, otherwise it returns -EINVAL and *res is set to 0. 248 */ 249int strict_strtoll(const char *cp, unsigned int base, long long *res) 250{ 251 int ret; 252 if (*cp == '-') { 253 ret = strict_strtoull(cp + 1, base, (unsigned long long *)res); 254 if (!ret) 255 *res = -(*res); 256 } else { 257 ret = strict_strtoull(cp, base, (unsigned long long *)res); 258 } 259 260 return ret; 261} 262EXPORT_SYMBOL(strict_strtoll); 263 264static noinline_for_stack 265int skip_atoi(const char **s) 266{ 267 int i = 0; 268 269 while (isdigit(**s)) 270 i = i*10 + *((*s)++) - '0'; 271 272 return i; 273} 274 275/* Decimal conversion is by far the most typical, and is used 276 * for /proc and /sys data. This directly impacts e.g. top performance 277 * with many processes running. We optimize it for speed 278 * using code from 279 * http://www.cs.uiowa.edu/~jones/bcd/decimal.html 280 * (with permission from the author, Douglas W. Jones). */ 281 282/* Formats correctly any integer in [0,99999]. 283 * Outputs from one to five digits depending on input. 284 * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */ 285static noinline_for_stack 286char *put_dec_trunc(char *buf, unsigned q) 287{ 288 unsigned d3, d2, d1, d0; 289 d1 = (q>>4) & 0xf; 290 d2 = (q>>8) & 0xf; 291 d3 = (q>>12); 292 293 d0 = 6*(d3 + d2 + d1) + (q & 0xf); 294 q = (d0 * 0xcd) >> 11; 295 d0 = d0 - 10*q; 296 *buf++ = d0 + '0'; /* least significant digit */ 297 d1 = q + 9*d3 + 5*d2 + d1; 298 if (d1 != 0) { 299 q = (d1 * 0xcd) >> 11; 300 d1 = d1 - 10*q; 301 *buf++ = d1 + '0'; /* next digit */ 302 303 d2 = q + 2*d2; 304 if ((d2 != 0) || (d3 != 0)) { 305 q = (d2 * 0xd) >> 7; 306 d2 = d2 - 10*q; 307 *buf++ = d2 + '0'; /* next digit */ 308 309 d3 = q + 4*d3; 310 if (d3 != 0) { 311 q = (d3 * 0xcd) >> 11; 312 d3 = d3 - 10*q; 313 *buf++ = d3 + '0'; /* next digit */ 314 if (q != 0) 315 *buf++ = q + '0'; /* most sign. digit */ 316 } 317 } 318 } 319 320 return buf; 321} 322/* Same with if's removed. Always emits five digits */ 323static noinline_for_stack 324char *put_dec_full(char *buf, unsigned q) 325{ 326 /* BTW, if q is in [0,9999], 8-bit ints will be enough, */ 327 /* but anyway, gcc produces better code with full-sized ints */ 328 unsigned d3, d2, d1, d0; 329 d1 = (q>>4) & 0xf; 330 d2 = (q>>8) & 0xf; 331 d3 = (q>>12); 332 333 /* 334 * Possible ways to approx. divide by 10 335 * gcc -O2 replaces multiply with shifts and adds 336 * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386) 337 * (x * 0x67) >> 10: 1100111 338 * (x * 0x34) >> 9: 110100 - same 339 * (x * 0x1a) >> 8: 11010 - same 340 * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386) 341 */ 342 d0 = 6*(d3 + d2 + d1) + (q & 0xf); 343 q = (d0 * 0xcd) >> 11; 344 d0 = d0 - 10*q; 345 *buf++ = d0 + '0'; 346 d1 = q + 9*d3 + 5*d2 + d1; 347 q = (d1 * 0xcd) >> 11; 348 d1 = d1 - 10*q; 349 *buf++ = d1 + '0'; 350 351 d2 = q + 2*d2; 352 q = (d2 * 0xd) >> 7; 353 d2 = d2 - 10*q; 354 *buf++ = d2 + '0'; 355 356 d3 = q + 4*d3; 357 q = (d3 * 0xcd) >> 11; /* - shorter code */ 358 /* q = (d3 * 0x67) >> 10; - would also work */ 359 d3 = d3 - 10*q; 360 *buf++ = d3 + '0'; 361 *buf++ = q + '0'; 362 363 return buf; 364} 365/* No inlining helps gcc to use registers better */ 366static noinline_for_stack 367char *put_dec(char *buf, unsigned long long num) 368{ 369 while (1) { 370 unsigned rem; 371 if (num < 100000) 372 return put_dec_trunc(buf, num); 373 rem = do_div(num, 100000); 374 buf = put_dec_full(buf, rem); 375 } 376} 377 378#define ZEROPAD 1 /* pad with zero */ 379#define SIGN 2 /* unsigned/signed long */ 380#define PLUS 4 /* show plus */ 381#define SPACE 8 /* space if plus */ 382#define LEFT 16 /* left justified */ 383#define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */ 384#define SPECIAL 64 /* prefix hex with "0x", octal with "0" */ 385 386enum format_type { 387 FORMAT_TYPE_NONE, /* Just a string part */ 388 FORMAT_TYPE_WIDTH, 389 FORMAT_TYPE_PRECISION, 390 FORMAT_TYPE_CHAR, 391 FORMAT_TYPE_STR, 392 FORMAT_TYPE_PTR, 393 FORMAT_TYPE_PERCENT_CHAR, 394 FORMAT_TYPE_INVALID, 395 FORMAT_TYPE_LONG_LONG, 396 FORMAT_TYPE_ULONG, 397 FORMAT_TYPE_LONG, 398 FORMAT_TYPE_UBYTE, 399 FORMAT_TYPE_BYTE, 400 FORMAT_TYPE_USHORT, 401 FORMAT_TYPE_SHORT, 402 FORMAT_TYPE_UINT, 403 FORMAT_TYPE_INT, 404 FORMAT_TYPE_NRCHARS, 405 FORMAT_TYPE_SIZE_T, 406 FORMAT_TYPE_PTRDIFF 407}; 408 409struct printf_spec { 410 u8 type; /* format_type enum */ 411 u8 flags; /* flags to number() */ 412 u8 base; /* number base, 8, 10 or 16 only */ 413 u8 qualifier; /* number qualifier, one of 'hHlLtzZ' */ 414 s16 field_width; /* width of output field */ 415 s16 precision; /* # of digits/chars */ 416}; 417 418static noinline_for_stack 419char *number(char *buf, char *end, unsigned long long num, 420 struct printf_spec spec) 421{ 422 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */ 423 static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */ 424 425 char tmp[66]; 426 char sign; 427 char locase; 428 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10); 429 int i; 430 431 /* locase = 0 or 0x20. ORing digits or letters with 'locase' 432 * produces same digits or (maybe lowercased) letters */ 433 locase = (spec.flags & SMALL); 434 if (spec.flags & LEFT) 435 spec.flags &= ~ZEROPAD; 436 sign = 0; 437 if (spec.flags & SIGN) { 438 if ((signed long long)num < 0) { 439 sign = '-'; 440 num = -(signed long long)num; 441 spec.field_width--; 442 } else if (spec.flags & PLUS) { 443 sign = '+'; 444 spec.field_width--; 445 } else if (spec.flags & SPACE) { 446 sign = ' '; 447 spec.field_width--; 448 } 449 } 450 if (need_pfx) { 451 spec.field_width--; 452 if (spec.base == 16) 453 spec.field_width--; 454 } 455 456 /* generate full string in tmp[], in reverse order */ 457 i = 0; 458 if (num == 0) 459 tmp[i++] = '0'; 460 /* Generic code, for any base: 461 else do { 462 tmp[i++] = (digits[do_div(num,base)] | locase); 463 } while (num != 0); 464 */ 465 else if (spec.base != 10) { /* 8 or 16 */ 466 int mask = spec.base - 1; 467 int shift = 3; 468 469 if (spec.base == 16) 470 shift = 4; 471 do { 472 tmp[i++] = (digits[((unsigned char)num) & mask] | locase); 473 num >>= shift; 474 } while (num); 475 } else { /* base 10 */ 476 i = put_dec(tmp, num) - tmp; 477 } 478 479 /* printing 100 using %2d gives "100", not "00" */ 480 if (i > spec.precision) 481 spec.precision = i; 482 /* leading space padding */ 483 spec.field_width -= spec.precision; 484 if (!(spec.flags & (ZEROPAD+LEFT))) { 485 while (--spec.field_width >= 0) { 486 if (buf < end) 487 *buf = ' '; 488 ++buf; 489 } 490 } 491 /* sign */ 492 if (sign) { 493 if (buf < end) 494 *buf = sign; 495 ++buf; 496 } 497 /* "0x" / "0" prefix */ 498 if (need_pfx) { 499 if (buf < end) 500 *buf = '0'; 501 ++buf; 502 if (spec.base == 16) { 503 if (buf < end) 504 *buf = ('X' | locase); 505 ++buf; 506 } 507 } 508 /* zero or space padding */ 509 if (!(spec.flags & LEFT)) { 510 char c = (spec.flags & ZEROPAD) ? '0' : ' '; 511 while (--spec.field_width >= 0) { 512 if (buf < end) 513 *buf = c; 514 ++buf; 515 } 516 } 517 /* hmm even more zero padding? */ 518 while (i <= --spec.precision) { 519 if (buf < end) 520 *buf = '0'; 521 ++buf; 522 } 523 /* actual digits of result */ 524 while (--i >= 0) { 525 if (buf < end) 526 *buf = tmp[i]; 527 ++buf; 528 } 529 /* trailing space padding */ 530 while (--spec.field_width >= 0) { 531 if (buf < end) 532 *buf = ' '; 533 ++buf; 534 } 535 536 return buf; 537} 538 539static noinline_for_stack 540char *string(char *buf, char *end, const char *s, struct printf_spec spec) 541{ 542 int len, i; 543 544 if ((unsigned long)s < PAGE_SIZE) 545 s = "(null)"; 546 547 len = strnlen(s, spec.precision); 548 549 if (!(spec.flags & LEFT)) { 550 while (len < spec.field_width--) { 551 if (buf < end) 552 *buf = ' '; 553 ++buf; 554 } 555 } 556 for (i = 0; i < len; ++i) { 557 if (buf < end) 558 *buf = *s; 559 ++buf; ++s; 560 } 561 while (len < spec.field_width--) { 562 if (buf < end) 563 *buf = ' '; 564 ++buf; 565 } 566 567 return buf; 568} 569 570static noinline_for_stack 571char *symbol_string(char *buf, char *end, void *ptr, 572 struct printf_spec spec, char ext) 573{ 574 unsigned long value = (unsigned long) ptr; 575#ifdef CONFIG_KALLSYMS 576 char sym[KSYM_SYMBOL_LEN]; 577 if (ext != 'f' && ext != 's') 578 sprint_symbol(sym, value); 579 else 580 kallsyms_lookup(value, NULL, NULL, NULL, sym); 581 582 return string(buf, end, sym, spec); 583#else 584 spec.field_width = 2 * sizeof(void *); 585 spec.flags |= SPECIAL | SMALL | ZEROPAD; 586 spec.base = 16; 587 588 return number(buf, end, value, spec); 589#endif 590} 591 592static noinline_for_stack 593char *resource_string(char *buf, char *end, struct resource *res, 594 struct printf_spec spec, const char *fmt) 595{ 596#ifndef IO_RSRC_PRINTK_SIZE 597#define IO_RSRC_PRINTK_SIZE 6 598#endif 599 600#ifndef MEM_RSRC_PRINTK_SIZE 601#define MEM_RSRC_PRINTK_SIZE 10 602#endif 603 static const struct printf_spec io_spec = { 604 .base = 16, 605 .field_width = IO_RSRC_PRINTK_SIZE, 606 .precision = -1, 607 .flags = SPECIAL | SMALL | ZEROPAD, 608 }; 609 static const struct printf_spec mem_spec = { 610 .base = 16, 611 .field_width = MEM_RSRC_PRINTK_SIZE, 612 .precision = -1, 613 .flags = SPECIAL | SMALL | ZEROPAD, 614 }; 615 static const struct printf_spec bus_spec = { 616 .base = 16, 617 .field_width = 2, 618 .precision = -1, 619 .flags = SMALL | ZEROPAD, 620 }; 621 static const struct printf_spec dec_spec = { 622 .base = 10, 623 .precision = -1, 624 .flags = 0, 625 }; 626 static const struct printf_spec str_spec = { 627 .field_width = -1, 628 .precision = 10, 629 .flags = LEFT, 630 }; 631 static const struct printf_spec flag_spec = { 632 .base = 16, 633 .precision = -1, 634 .flags = SPECIAL | SMALL, 635 }; 636 637 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) 638 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ 639#define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) 640#define FLAG_BUF_SIZE (2 * sizeof(res->flags)) 641#define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") 642#define RAW_BUF_SIZE sizeof("[mem - flags 0x]") 643 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 644 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; 645 646 char *p = sym, *pend = sym + sizeof(sym); 647 int decode = (fmt[0] == 'R') ? 1 : 0; 648 const struct printf_spec *specp; 649 650 *p++ = '['; 651 if (res->flags & IORESOURCE_IO) { 652 p = string(p, pend, "io ", str_spec); 653 specp = &io_spec; 654 } else if (res->flags & IORESOURCE_MEM) { 655 p = string(p, pend, "mem ", str_spec); 656 specp = &mem_spec; 657 } else if (res->flags & IORESOURCE_IRQ) { 658 p = string(p, pend, "irq ", str_spec); 659 specp = &dec_spec; 660 } else if (res->flags & IORESOURCE_DMA) { 661 p = string(p, pend, "dma ", str_spec); 662 specp = &dec_spec; 663 } else if (res->flags & IORESOURCE_BUS) { 664 p = string(p, pend, "bus ", str_spec); 665 specp = &bus_spec; 666 } else { 667 p = string(p, pend, "??? ", str_spec); 668 specp = &mem_spec; 669 decode = 0; 670 } 671 p = number(p, pend, res->start, *specp); 672 if (res->start != res->end) { 673 *p++ = '-'; 674 p = number(p, pend, res->end, *specp); 675 } 676 if (decode) { 677 if (res->flags & IORESOURCE_MEM_64) 678 p = string(p, pend, " 64bit", str_spec); 679 if (res->flags & IORESOURCE_PREFETCH) 680 p = string(p, pend, " pref", str_spec); 681 if (res->flags & IORESOURCE_WINDOW) 682 p = string(p, pend, " window", str_spec); 683 if (res->flags & IORESOURCE_DISABLED) 684 p = string(p, pend, " disabled", str_spec); 685 } else { 686 p = string(p, pend, " flags ", str_spec); 687 p = number(p, pend, res->flags, flag_spec); 688 } 689 *p++ = ']'; 690 *p = '\0'; 691 692 return string(buf, end, sym, spec); 693} 694 695static noinline_for_stack 696char *mac_address_string(char *buf, char *end, u8 *addr, 697 struct printf_spec spec, const char *fmt) 698{ 699 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; 700 char *p = mac_addr; 701 int i; 702 char separator; 703 704 if (fmt[1] == 'F') { /* FDDI canonical format */ 705 separator = '-'; 706 } else { 707 separator = ':'; 708 } 709 710 for (i = 0; i < 6; i++) { 711 p = pack_hex_byte(p, addr[i]); 712 if (fmt[0] == 'M' && i != 5) 713 *p++ = separator; 714 } 715 *p = '\0'; 716 717 return string(buf, end, mac_addr, spec); 718} 719 720static noinline_for_stack 721char *ip4_string(char *p, const u8 *addr, const char *fmt) 722{ 723 int i; 724 bool leading_zeros = (fmt[0] == 'i'); 725 int index; 726 int step; 727 728 switch (fmt[2]) { 729 case 'h': 730#ifdef __BIG_ENDIAN 731 index = 0; 732 step = 1; 733#else 734 index = 3; 735 step = -1; 736#endif 737 break; 738 case 'l': 739 index = 3; 740 step = -1; 741 break; 742 case 'n': 743 case 'b': 744 default: 745 index = 0; 746 step = 1; 747 break; 748 } 749 for (i = 0; i < 4; i++) { 750 char temp[3]; /* hold each IP quad in reverse order */ 751 int digits = put_dec_trunc(temp, addr[index]) - temp; 752 if (leading_zeros) { 753 if (digits < 3) 754 *p++ = '0'; 755 if (digits < 2) 756 *p++ = '0'; 757 } 758 /* reverse the digits in the quad */ 759 while (digits--) 760 *p++ = temp[digits]; 761 if (i < 3) 762 *p++ = '.'; 763 index += step; 764 } 765 *p = '\0'; 766 767 return p; 768} 769 770static noinline_for_stack 771char *ip6_compressed_string(char *p, const char *addr) 772{ 773 int i, j, range; 774 unsigned char zerolength[8]; 775 int longest = 1; 776 int colonpos = -1; 777 u16 word; 778 u8 hi, lo; 779 bool needcolon = false; 780 bool useIPv4; 781 struct in6_addr in6; 782 783 memcpy(&in6, addr, sizeof(struct in6_addr)); 784 785 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6); 786 787 memset(zerolength, 0, sizeof(zerolength)); 788 789 if (useIPv4) 790 range = 6; 791 else 792 range = 8; 793 794 /* find position of longest 0 run */ 795 for (i = 0; i < range; i++) { 796 for (j = i; j < range; j++) { 797 if (in6.s6_addr16[j] != 0) 798 break; 799 zerolength[i]++; 800 } 801 } 802 for (i = 0; i < range; i++) { 803 if (zerolength[i] > longest) { 804 longest = zerolength[i]; 805 colonpos = i; 806 } 807 } 808 809 /* emit address */ 810 for (i = 0; i < range; i++) { 811 if (i == colonpos) { 812 if (needcolon || i == 0) 813 *p++ = ':'; 814 *p++ = ':'; 815 needcolon = false; 816 i += longest - 1; 817 continue; 818 } 819 if (needcolon) { 820 *p++ = ':'; 821 needcolon = false; 822 } 823 /* hex u16 without leading 0s */ 824 word = ntohs(in6.s6_addr16[i]); 825 hi = word >> 8; 826 lo = word & 0xff; 827 if (hi) { 828 if (hi > 0x0f) 829 p = pack_hex_byte(p, hi); 830 else 831 *p++ = hex_asc_lo(hi); 832 p = pack_hex_byte(p, lo); 833 } 834 else if (lo > 0x0f) 835 p = pack_hex_byte(p, lo); 836 else 837 *p++ = hex_asc_lo(lo); 838 needcolon = true; 839 } 840 841 if (useIPv4) { 842 if (needcolon) 843 *p++ = ':'; 844 p = ip4_string(p, &in6.s6_addr[12], "I4"); 845 } 846 *p = '\0'; 847 848 return p; 849} 850 851static noinline_for_stack 852char *ip6_string(char *p, const char *addr, const char *fmt) 853{ 854 int i; 855 856 for (i = 0; i < 8; i++) { 857 p = pack_hex_byte(p, *addr++); 858 p = pack_hex_byte(p, *addr++); 859 if (fmt[0] == 'I' && i != 7) 860 *p++ = ':'; 861 } 862 *p = '\0'; 863 864 return p; 865} 866 867static noinline_for_stack 868char *ip6_addr_string(char *buf, char *end, const u8 *addr, 869 struct printf_spec spec, const char *fmt) 870{ 871 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 872 873 if (fmt[0] == 'I' && fmt[2] == 'c') 874 ip6_compressed_string(ip6_addr, addr); 875 else 876 ip6_string(ip6_addr, addr, fmt); 877 878 return string(buf, end, ip6_addr, spec); 879} 880 881static noinline_for_stack 882char *ip4_addr_string(char *buf, char *end, const u8 *addr, 883 struct printf_spec spec, const char *fmt) 884{ 885 char ip4_addr[sizeof("255.255.255.255")]; 886 887 ip4_string(ip4_addr, addr, fmt); 888 889 return string(buf, end, ip4_addr, spec); 890} 891 892static noinline_for_stack 893char *uuid_string(char *buf, char *end, const u8 *addr, 894 struct printf_spec spec, const char *fmt) 895{ 896 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")]; 897 char *p = uuid; 898 int i; 899 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15}; 900 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15}; 901 const u8 *index = be; 902 bool uc = false; 903 904 switch (*(++fmt)) { 905 case 'L': 906 uc = true; /* fall-through */ 907 case 'l': 908 index = le; 909 break; 910 case 'B': 911 uc = true; 912 break; 913 } 914 915 for (i = 0; i < 16; i++) { 916 p = pack_hex_byte(p, addr[index[i]]); 917 switch (i) { 918 case 3: 919 case 5: 920 case 7: 921 case 9: 922 *p++ = '-'; 923 break; 924 } 925 } 926 927 *p = 0; 928 929 if (uc) { 930 p = uuid; 931 do { 932 *p = toupper(*p); 933 } while (*(++p)); 934 } 935 936 return string(buf, end, uuid, spec); 937} 938 939static noinline_for_stack 940char *pointer(const char *fmt, char *buf, char *end, void *ptr, 941 struct printf_spec spec) 942{ 943 if (!ptr) 944 return string(buf, end, "(null)", spec); 945 946 switch (*fmt) { 947 case 'F': 948 case 'f': 949 ptr = dereference_function_descriptor(ptr); 950 /* Fallthrough */ 951 case 'S': 952 case 's': 953 return symbol_string(buf, end, ptr, spec, *fmt); 954 case 'R': 955 case 'r': 956 return resource_string(buf, end, ptr, spec, fmt); 957 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 958 case 'm': /* Contiguous: 000102030405 */ 959 /* [mM]F (FDDI, bit reversed) */ 960 return mac_address_string(buf, end, ptr, spec, fmt); 961 case 'I': /* Formatted IP supported 962 * 4: 1.2.3.4 963 * 6: 0001:0203:...:0708 964 * 6c: 1::708 or 1::1.2.3.4 965 */ 966 case 'i': /* Contiguous: 967 * 4: 001.002.003.004 968 * 6: 000102...0f 969 */ 970 switch (fmt[1]) { 971 case '6': 972 return ip6_addr_string(buf, end, ptr, spec, fmt); 973 case '4': 974 return ip4_addr_string(buf, end, ptr, spec, fmt); 975 } 976 break; 977 case 'U': 978 return uuid_string(buf, end, ptr, spec, fmt); 979 case 'V': 980 return buf + vsnprintf(buf, end - buf, 981 ((struct va_format *)ptr)->fmt, 982 *(((struct va_format *)ptr)->va)); 983 } 984 spec.flags |= SMALL; 985 if (spec.field_width == -1) { 986 spec.field_width = 2*sizeof(void *); 987 spec.flags |= ZEROPAD; 988 } 989 spec.base = 16; 990 991 return number(buf, end, (unsigned long) ptr, spec); 992} 993 994/* 995 * Helper function to decode printf style format. 996 * Each call decode a token from the format and return the 997 * number of characters read (or likely the delta where it wants 998 * to go on the next call). 999 * The decoded token is returned through the parameters 1000 * 1001 * 'h', 'l', or 'L' for integer fields 1002 * 'z' support added 23/7/1999 S.H. 1003 * 'z' changed to 'Z' --davidm 1/25/99 1004 * 't' added for ptrdiff_t 1005 * 1006 * @fmt: the format string 1007 * @type of the token returned 1008 * @flags: various flags such as +, -, # tokens.. 1009 * @field_width: overwritten width 1010 * @base: base of the number (octal, hex, ...) 1011 * @precision: precision of a number 1012 * @qualifier: qualifier of a number (long, size_t, ...) 1013 */ 1014static noinline_for_stack 1015int format_decode(const char *fmt, struct printf_spec *spec) 1016{ 1017 const char *start = fmt; 1018 1019 /* we finished early by reading the field width */ 1020 if (spec->type == FORMAT_TYPE_WIDTH) { 1021 if (spec->field_width < 0) { 1022 spec->field_width = -spec->field_width; 1023 spec->flags |= LEFT; 1024 } 1025 spec->type = FORMAT_TYPE_NONE; 1026 goto precision; 1027 } 1028 1029 /* we finished early by reading the precision */ 1030 if (spec->type == FORMAT_TYPE_PRECISION) { 1031 if (spec->precision < 0) 1032 spec->precision = 0; 1033 1034 spec->type = FORMAT_TYPE_NONE; 1035 goto qualifier; 1036 } 1037 1038 /* By default */ 1039 spec->type = FORMAT_TYPE_NONE; 1040 1041 for (; *fmt ; ++fmt) { 1042 if (*fmt == '%') 1043 break; 1044 } 1045 1046 /* Return the current non-format string */ 1047 if (fmt != start || !*fmt) 1048 return fmt - start; 1049 1050 /* Process flags */ 1051 spec->flags = 0; 1052 1053 while (1) { /* this also skips first '%' */ 1054 bool found = true; 1055 1056 ++fmt; 1057 1058 switch (*fmt) { 1059 case '-': spec->flags |= LEFT; break; 1060 case '+': spec->flags |= PLUS; break; 1061 case ' ': spec->flags |= SPACE; break; 1062 case '#': spec->flags |= SPECIAL; break; 1063 case '0': spec->flags |= ZEROPAD; break; 1064 default: found = false; 1065 } 1066 1067 if (!found) 1068 break; 1069 } 1070 1071 /* get field width */ 1072 spec->field_width = -1; 1073 1074 if (isdigit(*fmt)) 1075 spec->field_width = skip_atoi(&fmt); 1076 else if (*fmt == '*') { 1077 /* it's the next argument */ 1078 spec->type = FORMAT_TYPE_WIDTH; 1079 return ++fmt - start; 1080 } 1081 1082precision: 1083 /* get the precision */ 1084 spec->precision = -1; 1085 if (*fmt == '.') { 1086 ++fmt; 1087 if (isdigit(*fmt)) { 1088 spec->precision = skip_atoi(&fmt); 1089 if (spec->precision < 0) 1090 spec->precision = 0; 1091 } else if (*fmt == '*') { 1092 /* it's the next argument */ 1093 spec->type = FORMAT_TYPE_PRECISION; 1094 return ++fmt - start; 1095 } 1096 } 1097 1098qualifier: 1099 /* get the conversion qualifier */ 1100 spec->qualifier = -1; 1101 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' || 1102 TOLOWER(*fmt) == 'z' || *fmt == 't') { 1103 spec->qualifier = *fmt++; 1104 if (unlikely(spec->qualifier == *fmt)) { 1105 if (spec->qualifier == 'l') { 1106 spec->qualifier = 'L'; 1107 ++fmt; 1108 } else if (spec->qualifier == 'h') { 1109 spec->qualifier = 'H'; 1110 ++fmt; 1111 } 1112 } 1113 } 1114 1115 /* default base */ 1116 spec->base = 10; 1117 switch (*fmt) { 1118 case 'c': 1119 spec->type = FORMAT_TYPE_CHAR; 1120 return ++fmt - start; 1121 1122 case 's': 1123 spec->type = FORMAT_TYPE_STR; 1124 return ++fmt - start; 1125 1126 case 'p': 1127 spec->type = FORMAT_TYPE_PTR; 1128 return fmt - start; 1129 /* skip alnum */ 1130 1131 case 'n': 1132 spec->type = FORMAT_TYPE_NRCHARS; 1133 return ++fmt - start; 1134 1135 case '%': 1136 spec->type = FORMAT_TYPE_PERCENT_CHAR; 1137 return ++fmt - start; 1138 1139 /* integer number formats - set up the flags and "break" */ 1140 case 'o': 1141 spec->base = 8; 1142 break; 1143 1144 case 'x': 1145 spec->flags |= SMALL; 1146 1147 case 'X': 1148 spec->base = 16; 1149 break; 1150 1151 case 'd': 1152 case 'i': 1153 spec->flags |= SIGN; 1154 case 'u': 1155 break; 1156 1157 default: 1158 spec->type = FORMAT_TYPE_INVALID; 1159 return fmt - start; 1160 } 1161 1162 if (spec->qualifier == 'L') 1163 spec->type = FORMAT_TYPE_LONG_LONG; 1164 else if (spec->qualifier == 'l') { 1165 if (spec->flags & SIGN) 1166 spec->type = FORMAT_TYPE_LONG; 1167 else 1168 spec->type = FORMAT_TYPE_ULONG; 1169 } else if (TOLOWER(spec->qualifier) == 'z') { 1170 spec->type = FORMAT_TYPE_SIZE_T; 1171 } else if (spec->qualifier == 't') { 1172 spec->type = FORMAT_TYPE_PTRDIFF; 1173 } else if (spec->qualifier == 'H') { 1174 if (spec->flags & SIGN) 1175 spec->type = FORMAT_TYPE_BYTE; 1176 else 1177 spec->type = FORMAT_TYPE_UBYTE; 1178 } else if (spec->qualifier == 'h') { 1179 if (spec->flags & SIGN) 1180 spec->type = FORMAT_TYPE_SHORT; 1181 else 1182 spec->type = FORMAT_TYPE_USHORT; 1183 } else { 1184 if (spec->flags & SIGN) 1185 spec->type = FORMAT_TYPE_INT; 1186 else 1187 spec->type = FORMAT_TYPE_UINT; 1188 } 1189 1190 return ++fmt - start; 1191} 1192 1193/** 1194 * vsnprintf - Format a string and place it in a buffer 1195 * @buf: The buffer to place the result into 1196 * @size: The size of the buffer, including the trailing null space 1197 * @fmt: The format string to use 1198 * @args: Arguments for the format string 1199 * 1200 * This function follows C99 vsnprintf, but has some extensions: 1201 * %pS output the name of a text symbol with offset 1202 * %ps output the name of a text symbol without offset 1203 * %pF output the name of a function pointer with its offset 1204 * %pf output the name of a function pointer without its offset 1205 * %pR output the address range in a struct resource with decoded flags 1206 * %pr output the address range in a struct resource with raw flags 1207 * %pM output a 6-byte MAC address with colons 1208 * %pm output a 6-byte MAC address without colons 1209 * %pI4 print an IPv4 address without leading zeros 1210 * %pi4 print an IPv4 address with leading zeros 1211 * %pI6 print an IPv6 address with colons 1212 * %pi6 print an IPv6 address without colons 1213 * %pI6c print an IPv6 address as specified by 1214 * http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-00 1215 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper 1216 * case. 1217 * %n is ignored 1218 * 1219 * The return value is the number of characters which would 1220 * be generated for the given input, excluding the trailing 1221 * '\0', as per ISO C99. If you want to have the exact 1222 * number of characters written into @buf as return value 1223 * (not including the trailing '\0'), use vscnprintf(). If the 1224 * return is greater than or equal to @size, the resulting 1225 * string is truncated. 1226 * 1227 * Call this function if you are already dealing with a va_list. 1228 * You probably want snprintf() instead. 1229 */ 1230int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) 1231{ 1232 unsigned long long num; 1233 char *str, *end; 1234 struct printf_spec spec = {0}; 1235 1236 /* Reject out-of-range values early. Large positive sizes are 1237 used for unknown buffer sizes. */ 1238 if (WARN_ON_ONCE((int) size < 0)) 1239 return 0; 1240 1241 str = buf; 1242 end = buf + size; 1243 1244 /* Make sure end is always >= buf */ 1245 if (end < buf) { 1246 end = ((void *)-1); 1247 size = end - buf; 1248 } 1249 1250 while (*fmt) { 1251 const char *old_fmt = fmt; 1252 int read = format_decode(fmt, &spec); 1253 1254 fmt += read; 1255 1256 switch (spec.type) { 1257 case FORMAT_TYPE_NONE: { 1258 int copy = read; 1259 if (str < end) { 1260 if (copy > end - str) 1261 copy = end - str; 1262 memcpy(str, old_fmt, copy); 1263 } 1264 str += read; 1265 break; 1266 } 1267 1268 case FORMAT_TYPE_WIDTH: 1269 spec.field_width = va_arg(args, int); 1270 break; 1271 1272 case FORMAT_TYPE_PRECISION: 1273 spec.precision = va_arg(args, int); 1274 break; 1275 1276 case FORMAT_TYPE_CHAR: { 1277 char c; 1278 1279 if (!(spec.flags & LEFT)) { 1280 while (--spec.field_width > 0) { 1281 if (str < end) 1282 *str = ' '; 1283 ++str; 1284 1285 } 1286 } 1287 c = (unsigned char) va_arg(args, int); 1288 if (str < end) 1289 *str = c; 1290 ++str; 1291 while (--spec.field_width > 0) { 1292 if (str < end) 1293 *str = ' '; 1294 ++str; 1295 } 1296 break; 1297 } 1298 1299 case FORMAT_TYPE_STR: 1300 str = string(str, end, va_arg(args, char *), spec); 1301 break; 1302 1303 case FORMAT_TYPE_PTR: 1304 str = pointer(fmt+1, str, end, va_arg(args, void *), 1305 spec); 1306 while (isalnum(*fmt)) 1307 fmt++; 1308 break; 1309 1310 case FORMAT_TYPE_PERCENT_CHAR: 1311 if (str < end) 1312 *str = '%'; 1313 ++str; 1314 break; 1315 1316 case FORMAT_TYPE_INVALID: 1317 if (str < end) 1318 *str = '%'; 1319 ++str; 1320 break; 1321 1322 case FORMAT_TYPE_NRCHARS: { 1323 u8 qualifier = spec.qualifier; 1324 1325 if (qualifier == 'l') { 1326 long *ip = va_arg(args, long *); 1327 *ip = (str - buf); 1328 } else if (TOLOWER(qualifier) == 'z') { 1329 size_t *ip = va_arg(args, size_t *); 1330 *ip = (str - buf); 1331 } else { 1332 int *ip = va_arg(args, int *); 1333 *ip = (str - buf); 1334 } 1335 break; 1336 } 1337 1338 default: 1339 switch (spec.type) { 1340 case FORMAT_TYPE_LONG_LONG: 1341 num = va_arg(args, long long); 1342 break; 1343 case FORMAT_TYPE_ULONG: 1344 num = va_arg(args, unsigned long); 1345 break; 1346 case FORMAT_TYPE_LONG: 1347 num = va_arg(args, long); 1348 break; 1349 case FORMAT_TYPE_SIZE_T: 1350 num = va_arg(args, size_t); 1351 break; 1352 case FORMAT_TYPE_PTRDIFF: 1353 num = va_arg(args, ptrdiff_t); 1354 break; 1355 case FORMAT_TYPE_UBYTE: 1356 num = (unsigned char) va_arg(args, int); 1357 break; 1358 case FORMAT_TYPE_BYTE: 1359 num = (signed char) va_arg(args, int); 1360 break; 1361 case FORMAT_TYPE_USHORT: 1362 num = (unsigned short) va_arg(args, int); 1363 break; 1364 case FORMAT_TYPE_SHORT: 1365 num = (short) va_arg(args, int); 1366 break; 1367 case FORMAT_TYPE_INT: 1368 num = (int) va_arg(args, int); 1369 break; 1370 default: 1371 num = va_arg(args, unsigned int); 1372 } 1373 1374 str = number(str, end, num, spec); 1375 } 1376 } 1377 1378 if (size > 0) { 1379 if (str < end) 1380 *str = '\0'; 1381 else 1382 end[-1] = '\0'; 1383 } 1384 1385 /* the trailing null byte doesn't count towards the total */ 1386 return str-buf; 1387 1388} 1389EXPORT_SYMBOL(vsnprintf); 1390 1391/** 1392 * vscnprintf - Format a string and place it in a buffer 1393 * @buf: The buffer to place the result into 1394 * @size: The size of the buffer, including the trailing null space 1395 * @fmt: The format string to use 1396 * @args: Arguments for the format string 1397 * 1398 * The return value is the number of characters which have been written into 1399 * the @buf not including the trailing '\0'. If @size is <= 0 the function 1400 * returns 0. 1401 * 1402 * Call this function if you are already dealing with a va_list. 1403 * You probably want scnprintf() instead. 1404 * 1405 * See the vsnprintf() documentation for format string extensions over C99. 1406 */ 1407int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 1408{ 1409 int i; 1410 1411 i = vsnprintf(buf, size, fmt, args); 1412 1413 return (i >= size) ? (size - 1) : i; 1414} 1415EXPORT_SYMBOL(vscnprintf); 1416 1417/** 1418 * snprintf - Format a string and place it in a buffer 1419 * @buf: The buffer to place the result into 1420 * @size: The size of the buffer, including the trailing null space 1421 * @fmt: The format string to use 1422 * @...: Arguments for the format string 1423 * 1424 * The return value is the number of characters which would be 1425 * generated for the given input, excluding the trailing null, 1426 * as per ISO C99. If the return is greater than or equal to 1427 * @size, the resulting string is truncated. 1428 * 1429 * See the vsnprintf() documentation for format string extensions over C99. 1430 */ 1431int snprintf(char *buf, size_t size, const char *fmt, ...) 1432{ 1433 va_list args; 1434 int i; 1435 1436 va_start(args, fmt); 1437 i = vsnprintf(buf, size, fmt, args); 1438 va_end(args); 1439 1440 return i; 1441} 1442EXPORT_SYMBOL(snprintf); 1443 1444/** 1445 * scnprintf - Format a string and place it in a buffer 1446 * @buf: The buffer to place the result into 1447 * @size: The size of the buffer, including the trailing null space 1448 * @fmt: The format string to use 1449 * @...: Arguments for the format string 1450 * 1451 * The return value is the number of characters written into @buf not including 1452 * the trailing '\0'. If @size is <= 0 the function returns 0. 1453 */ 1454 1455int scnprintf(char *buf, size_t size, const char *fmt, ...) 1456{ 1457 va_list args; 1458 int i; 1459 1460 va_start(args, fmt); 1461 i = vsnprintf(buf, size, fmt, args); 1462 va_end(args); 1463 1464 return (i >= size) ? (size - 1) : i; 1465} 1466EXPORT_SYMBOL(scnprintf); 1467 1468/** 1469 * vsprintf - Format a string and place it in a buffer 1470 * @buf: The buffer to place the result into 1471 * @fmt: The format string to use 1472 * @args: Arguments for the format string 1473 * 1474 * The function returns the number of characters written 1475 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid 1476 * buffer overflows. 1477 * 1478 * Call this function if you are already dealing with a va_list. 1479 * You probably want sprintf() instead. 1480 * 1481 * See the vsnprintf() documentation for format string extensions over C99. 1482 */ 1483int vsprintf(char *buf, const char *fmt, va_list args) 1484{ 1485 return vsnprintf(buf, INT_MAX, fmt, args); 1486} 1487EXPORT_SYMBOL(vsprintf); 1488 1489/** 1490 * sprintf - Format a string and place it in a buffer 1491 * @buf: The buffer to place the result into 1492 * @fmt: The format string to use 1493 * @...: Arguments for the format string 1494 * 1495 * The function returns the number of characters written 1496 * into @buf. Use snprintf() or scnprintf() in order to avoid 1497 * buffer overflows. 1498 * 1499 * See the vsnprintf() documentation for format string extensions over C99. 1500 */ 1501int sprintf(char *buf, const char *fmt, ...) 1502{ 1503 va_list args; 1504 int i; 1505 1506 va_start(args, fmt); 1507 i = vsnprintf(buf, INT_MAX, fmt, args); 1508 va_end(args); 1509 1510 return i; 1511} 1512EXPORT_SYMBOL(sprintf); 1513 1514#ifdef CONFIG_BINARY_PRINTF 1515/* 1516 * bprintf service: 1517 * vbin_printf() - VA arguments to binary data 1518 * bstr_printf() - Binary data to text string 1519 */ 1520 1521/** 1522 * vbin_printf - Parse a format string and place args' binary value in a buffer 1523 * @bin_buf: The buffer to place args' binary value 1524 * @size: The size of the buffer(by words(32bits), not characters) 1525 * @fmt: The format string to use 1526 * @args: Arguments for the format string 1527 * 1528 * The format follows C99 vsnprintf, except %n is ignored, and its argument 1529 * is skiped. 1530 * 1531 * The return value is the number of words(32bits) which would be generated for 1532 * the given input. 1533 * 1534 * NOTE: 1535 * If the return value is greater than @size, the resulting bin_buf is NOT 1536 * valid for bstr_printf(). 1537 */ 1538int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args) 1539{ 1540 struct printf_spec spec = {0}; 1541 char *str, *end; 1542 1543 str = (char *)bin_buf; 1544 end = (char *)(bin_buf + size); 1545 1546#define save_arg(type) \ 1547do { \ 1548 if (sizeof(type) == 8) { \ 1549 unsigned long long value; \ 1550 str = PTR_ALIGN(str, sizeof(u32)); \ 1551 value = va_arg(args, unsigned long long); \ 1552 if (str + sizeof(type) <= end) { \ 1553 *(u32 *)str = *(u32 *)&value; \ 1554 *(u32 *)(str + 4) = *((u32 *)&value + 1); \ 1555 } \ 1556 } else { \ 1557 unsigned long value; \ 1558 str = PTR_ALIGN(str, sizeof(type)); \ 1559 value = va_arg(args, int); \ 1560 if (str + sizeof(type) <= end) \ 1561 *(typeof(type) *)str = (type)value; \ 1562 } \ 1563 str += sizeof(type); \ 1564} while (0) 1565 1566 while (*fmt) { 1567 int read = format_decode(fmt, &spec); 1568 1569 fmt += read; 1570 1571 switch (spec.type) { 1572 case FORMAT_TYPE_NONE: 1573 case FORMAT_TYPE_INVALID: 1574 case FORMAT_TYPE_PERCENT_CHAR: 1575 break; 1576 1577 case FORMAT_TYPE_WIDTH: 1578 case FORMAT_TYPE_PRECISION: 1579 save_arg(int); 1580 break; 1581 1582 case FORMAT_TYPE_CHAR: 1583 save_arg(char); 1584 break; 1585 1586 case FORMAT_TYPE_STR: { 1587 const char *save_str = va_arg(args, char *); 1588 size_t len; 1589 1590 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE 1591 || (unsigned long)save_str < PAGE_SIZE) 1592 save_str = "(null)"; 1593 len = strlen(save_str) + 1; 1594 if (str + len < end) 1595 memcpy(str, save_str, len); 1596 str += len; 1597 break; 1598 } 1599 1600 case FORMAT_TYPE_PTR: 1601 save_arg(void *); 1602 /* skip all alphanumeric pointer suffixes */ 1603 while (isalnum(*fmt)) 1604 fmt++; 1605 break; 1606 1607 case FORMAT_TYPE_NRCHARS: { 1608 /* skip %n 's argument */ 1609 u8 qualifier = spec.qualifier; 1610 void *skip_arg; 1611 if (qualifier == 'l') 1612 skip_arg = va_arg(args, long *); 1613 else if (TOLOWER(qualifier) == 'z') 1614 skip_arg = va_arg(args, size_t *); 1615 else 1616 skip_arg = va_arg(args, int *); 1617 break; 1618 } 1619 1620 default: 1621 switch (spec.type) { 1622 1623 case FORMAT_TYPE_LONG_LONG: 1624 save_arg(long long); 1625 break; 1626 case FORMAT_TYPE_ULONG: 1627 case FORMAT_TYPE_LONG: 1628 save_arg(unsigned long); 1629 break; 1630 case FORMAT_TYPE_SIZE_T: 1631 save_arg(size_t); 1632 break; 1633 case FORMAT_TYPE_PTRDIFF: 1634 save_arg(ptrdiff_t); 1635 break; 1636 case FORMAT_TYPE_UBYTE: 1637 case FORMAT_TYPE_BYTE: 1638 save_arg(char); 1639 break; 1640 case FORMAT_TYPE_USHORT: 1641 case FORMAT_TYPE_SHORT: 1642 save_arg(short); 1643 break; 1644 default: 1645 save_arg(int); 1646 } 1647 } 1648 } 1649 1650 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 1651#undef save_arg 1652} 1653EXPORT_SYMBOL_GPL(vbin_printf); 1654 1655/** 1656 * bstr_printf - Format a string from binary arguments and place it in a buffer 1657 * @buf: The buffer to place the result into 1658 * @size: The size of the buffer, including the trailing null space 1659 * @fmt: The format string to use 1660 * @bin_buf: Binary arguments for the format string 1661 * 1662 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 1663 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 1664 * a binary buffer that generated by vbin_printf. 1665 * 1666 * The format follows C99 vsnprintf, but has some extensions: 1667 * see vsnprintf comment for details. 1668 * 1669 * The return value is the number of characters which would 1670 * be generated for the given input, excluding the trailing 1671 * '\0', as per ISO C99. If you want to have the exact 1672 * number of characters written into @buf as return value 1673 * (not including the trailing '\0'), use vscnprintf(). If the 1674 * return is greater than or equal to @size, the resulting 1675 * string is truncated. 1676 */ 1677int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) 1678{ 1679 struct printf_spec spec = {0}; 1680 char *str, *end; 1681 const char *args = (const char *)bin_buf; 1682 1683 if (WARN_ON_ONCE((int) size < 0)) 1684 return 0; 1685 1686 str = buf; 1687 end = buf + size; 1688 1689#define get_arg(type) \ 1690({ \ 1691 typeof(type) value; \ 1692 if (sizeof(type) == 8) { \ 1693 args = PTR_ALIGN(args, sizeof(u32)); \ 1694 *(u32 *)&value = *(u32 *)args; \ 1695 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 1696 } else { \ 1697 args = PTR_ALIGN(args, sizeof(type)); \ 1698 value = *(typeof(type) *)args; \ 1699 } \ 1700 args += sizeof(type); \ 1701 value; \ 1702}) 1703 1704 /* Make sure end is always >= buf */ 1705 if (end < buf) { 1706 end = ((void *)-1); 1707 size = end - buf; 1708 } 1709 1710 while (*fmt) { 1711 const char *old_fmt = fmt; 1712 int read = format_decode(fmt, &spec); 1713 1714 fmt += read; 1715 1716 switch (spec.type) { 1717 case FORMAT_TYPE_NONE: { 1718 int copy = read; 1719 if (str < end) { 1720 if (copy > end - str) 1721 copy = end - str; 1722 memcpy(str, old_fmt, copy); 1723 } 1724 str += read; 1725 break; 1726 } 1727 1728 case FORMAT_TYPE_WIDTH: 1729 spec.field_width = get_arg(int); 1730 break; 1731 1732 case FORMAT_TYPE_PRECISION: 1733 spec.precision = get_arg(int); 1734 break; 1735 1736 case FORMAT_TYPE_CHAR: { 1737 char c; 1738 1739 if (!(spec.flags & LEFT)) { 1740 while (--spec.field_width > 0) { 1741 if (str < end) 1742 *str = ' '; 1743 ++str; 1744 } 1745 } 1746 c = (unsigned char) get_arg(char); 1747 if (str < end) 1748 *str = c; 1749 ++str; 1750 while (--spec.field_width > 0) { 1751 if (str < end) 1752 *str = ' '; 1753 ++str; 1754 } 1755 break; 1756 } 1757 1758 case FORMAT_TYPE_STR: { 1759 const char *str_arg = args; 1760 args += strlen(str_arg) + 1; 1761 str = string(str, end, (char *)str_arg, spec); 1762 break; 1763 } 1764 1765 case FORMAT_TYPE_PTR: 1766 str = pointer(fmt+1, str, end, get_arg(void *), spec); 1767 while (isalnum(*fmt)) 1768 fmt++; 1769 break; 1770 1771 case FORMAT_TYPE_PERCENT_CHAR: 1772 case FORMAT_TYPE_INVALID: 1773 if (str < end) 1774 *str = '%'; 1775 ++str; 1776 break; 1777 1778 case FORMAT_TYPE_NRCHARS: 1779 /* skip */ 1780 break; 1781 1782 default: { 1783 unsigned long long num; 1784 1785 switch (spec.type) { 1786 1787 case FORMAT_TYPE_LONG_LONG: 1788 num = get_arg(long long); 1789 break; 1790 case FORMAT_TYPE_ULONG: 1791 case FORMAT_TYPE_LONG: 1792 num = get_arg(unsigned long); 1793 break; 1794 case FORMAT_TYPE_SIZE_T: 1795 num = get_arg(size_t); 1796 break; 1797 case FORMAT_TYPE_PTRDIFF: 1798 num = get_arg(ptrdiff_t); 1799 break; 1800 case FORMAT_TYPE_UBYTE: 1801 num = get_arg(unsigned char); 1802 break; 1803 case FORMAT_TYPE_BYTE: 1804 num = get_arg(signed char); 1805 break; 1806 case FORMAT_TYPE_USHORT: 1807 num = get_arg(unsigned short); 1808 break; 1809 case FORMAT_TYPE_SHORT: 1810 num = get_arg(short); 1811 break; 1812 case FORMAT_TYPE_UINT: 1813 num = get_arg(unsigned int); 1814 break; 1815 default: 1816 num = get_arg(int); 1817 } 1818 1819 str = number(str, end, num, spec); 1820 } /* default: */ 1821 } /* switch(spec.type) */ 1822 } /* while(*fmt) */ 1823 1824 if (size > 0) { 1825 if (str < end) 1826 *str = '\0'; 1827 else 1828 end[-1] = '\0'; 1829 } 1830 1831#undef get_arg 1832 1833 /* the trailing null byte doesn't count towards the total */ 1834 return str - buf; 1835} 1836EXPORT_SYMBOL_GPL(bstr_printf); 1837 1838/** 1839 * bprintf - Parse a format string and place args' binary value in a buffer 1840 * @bin_buf: The buffer to place args' binary value 1841 * @size: The size of the buffer(by words(32bits), not characters) 1842 * @fmt: The format string to use 1843 * @...: Arguments for the format string 1844 * 1845 * The function returns the number of words(u32) written 1846 * into @bin_buf. 1847 */ 1848int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) 1849{ 1850 va_list args; 1851 int ret; 1852 1853 va_start(args, fmt); 1854 ret = vbin_printf(bin_buf, size, fmt, args); 1855 va_end(args); 1856 1857 return ret; 1858} 1859EXPORT_SYMBOL_GPL(bprintf); 1860 1861#endif /* CONFIG_BINARY_PRINTF */ 1862 1863/** 1864 * vsscanf - Unformat a buffer into a list of arguments 1865 * @buf: input buffer 1866 * @fmt: format of buffer 1867 * @args: arguments 1868 */ 1869int vsscanf(const char *buf, const char *fmt, va_list args) 1870{ 1871 const char *str = buf; 1872 char *next; 1873 char digit; 1874 int num = 0; 1875 u8 qualifier; 1876 u8 base; 1877 s16 field_width; 1878 bool is_sign; 1879 1880 while (*fmt && *str) { 1881 /* skip any white space in format */ 1882 /* white space in format matchs any amount of 1883 * white space, including none, in the input. 1884 */ 1885 if (isspace(*fmt)) { 1886 fmt = skip_spaces(++fmt); 1887 str = skip_spaces(str); 1888 } 1889 1890 /* anything that is not a conversion must match exactly */ 1891 if (*fmt != '%' && *fmt) { 1892 if (*fmt++ != *str++) 1893 break; 1894 continue; 1895 } 1896 1897 if (!*fmt) 1898 break; 1899 ++fmt; 1900 1901 /* skip this conversion. 1902 * advance both strings to next white space 1903 */ 1904 if (*fmt == '*') { 1905 while (!isspace(*fmt) && *fmt != '%' && *fmt) 1906 fmt++; 1907 while (!isspace(*str) && *str) 1908 str++; 1909 continue; 1910 } 1911 1912 /* get field width */ 1913 field_width = -1; 1914 if (isdigit(*fmt)) 1915 field_width = skip_atoi(&fmt); 1916 1917 /* get conversion qualifier */ 1918 qualifier = -1; 1919 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' || 1920 TOLOWER(*fmt) == 'z') { 1921 qualifier = *fmt++; 1922 if (unlikely(qualifier == *fmt)) { 1923 if (qualifier == 'h') { 1924 qualifier = 'H'; 1925 fmt++; 1926 } else if (qualifier == 'l') { 1927 qualifier = 'L'; 1928 fmt++; 1929 } 1930 } 1931 } 1932 1933 if (!*fmt || !*str) 1934 break; 1935 1936 base = 10; 1937 is_sign = 0; 1938 1939 switch (*fmt++) { 1940 case 'c': 1941 { 1942 char *s = (char *)va_arg(args, char*); 1943 if (field_width == -1) 1944 field_width = 1; 1945 do { 1946 *s++ = *str++; 1947 } while (--field_width > 0 && *str); 1948 num++; 1949 } 1950 continue; 1951 case 's': 1952 { 1953 char *s = (char *)va_arg(args, char *); 1954 if (field_width == -1) 1955 field_width = SHRT_MAX; 1956 /* first, skip leading white space in buffer */ 1957 str = skip_spaces(str); 1958 1959 /* now copy until next white space */ 1960 while (*str && !isspace(*str) && field_width--) 1961 *s++ = *str++; 1962 *s = '\0'; 1963 num++; 1964 } 1965 continue; 1966 case 'n': 1967 /* return number of characters read so far */ 1968 { 1969 int *i = (int *)va_arg(args, int*); 1970 *i = str - buf; 1971 } 1972 continue; 1973 case 'o': 1974 base = 8; 1975 break; 1976 case 'x': 1977 case 'X': 1978 base = 16; 1979 break; 1980 case 'i': 1981 base = 0; 1982 case 'd': 1983 is_sign = 1; 1984 case 'u': 1985 break; 1986 case '%': 1987 /* looking for '%' in str */ 1988 if (*str++ != '%') 1989 return num; 1990 continue; 1991 default: 1992 /* invalid format; stop here */ 1993 return num; 1994 } 1995 1996 /* have some sort of integer conversion. 1997 * first, skip white space in buffer. 1998 */ 1999 str = skip_spaces(str); 2000 2001 digit = *str; 2002 if (is_sign && digit == '-') 2003 digit = *(str + 1); 2004 2005 if (!digit 2006 || (base == 16 && !isxdigit(digit)) 2007 || (base == 10 && !isdigit(digit)) 2008 || (base == 8 && (!isdigit(digit) || digit > '7')) 2009 || (base == 0 && !isdigit(digit))) 2010 break; 2011 2012 switch (qualifier) { 2013 case 'H': /* that's 'hh' in format */ 2014 if (is_sign) { 2015 signed char *s = (signed char *)va_arg(args, signed char *); 2016 *s = (signed char)simple_strtol(str, &next, base); 2017 } else { 2018 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *); 2019 *s = (unsigned char)simple_strtoul(str, &next, base); 2020 } 2021 break; 2022 case 'h': 2023 if (is_sign) { 2024 short *s = (short *)va_arg(args, short *); 2025 *s = (short)simple_strtol(str, &next, base); 2026 } else { 2027 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *); 2028 *s = (unsigned short)simple_strtoul(str, &next, base); 2029 } 2030 break; 2031 case 'l': 2032 if (is_sign) { 2033 long *l = (long *)va_arg(args, long *); 2034 *l = simple_strtol(str, &next, base); 2035 } else { 2036 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *); 2037 *l = simple_strtoul(str, &next, base); 2038 } 2039 break; 2040 case 'L': 2041 if (is_sign) { 2042 long long *l = (long long *)va_arg(args, long long *); 2043 *l = simple_strtoll(str, &next, base); 2044 } else { 2045 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *); 2046 *l = simple_strtoull(str, &next, base); 2047 } 2048 break; 2049 case 'Z': 2050 case 'z': 2051 { 2052 size_t *s = (size_t *)va_arg(args, size_t *); 2053 *s = (size_t)simple_strtoul(str, &next, base); 2054 } 2055 break; 2056 default: 2057 if (is_sign) { 2058 int *i = (int *)va_arg(args, int *); 2059 *i = (int)simple_strtol(str, &next, base); 2060 } else { 2061 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*); 2062 *i = (unsigned int)simple_strtoul(str, &next, base); 2063 } 2064 break; 2065 } 2066 num++; 2067 2068 if (!next) 2069 break; 2070 str = next; 2071 } 2072 2073 /* 2074 * Now we've come all the way through so either the input string or the 2075 * format ended. In the former case, there can be a %n at the current 2076 * position in the format that needs to be filled. 2077 */ 2078 if (*fmt == '%' && *(fmt + 1) == 'n') { 2079 int *p = (int *)va_arg(args, int *); 2080 *p = str - buf; 2081 } 2082 2083 return num; 2084} 2085EXPORT_SYMBOL(vsscanf); 2086 2087/** 2088 * sscanf - Unformat a buffer into a list of arguments 2089 * @buf: input buffer 2090 * @fmt: formatting of buffer 2091 * @...: resulting arguments 2092 */ 2093int sscanf(const char *buf, const char *fmt, ...) 2094{ 2095 va_list args; 2096 int i; 2097 2098 va_start(args, fmt); 2099 i = vsscanf(buf, fmt, args); 2100 va_end(args); 2101 2102 return i; 2103} 2104EXPORT_SYMBOL(sscanf); 2105