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