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