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 if (longest == 1) /* don't compress a single 0 */ 670 colonpos = -1; 671 672 /* emit address */ 673 for (i = 0; i < range; i++) { 674 if (i == colonpos) { 675 if (needcolon || i == 0) 676 *p++ = ':'; 677 *p++ = ':'; 678 needcolon = false; 679 i += longest - 1; 680 continue; 681 } 682 if (needcolon) { 683 *p++ = ':'; 684 needcolon = false; 685 } 686 /* hex u16 without leading 0s */ 687 word = ntohs(in6.s6_addr16[i]); 688 hi = word >> 8; 689 lo = word & 0xff; 690 if (hi) { 691 if (hi > 0x0f) 692 p = pack_hex_byte(p, hi); 693 else 694 *p++ = hex_asc_lo(hi); 695 p = pack_hex_byte(p, lo); 696 } 697 else if (lo > 0x0f) 698 p = pack_hex_byte(p, lo); 699 else 700 *p++ = hex_asc_lo(lo); 701 needcolon = true; 702 } 703 704 if (useIPv4) { 705 if (needcolon) 706 *p++ = ':'; 707 p = ip4_string(p, &in6.s6_addr[12], "I4"); 708 } 709 *p = '\0'; 710 711 return p; 712 } 713 714 static noinline_for_stack 715 char *ip6_string(char *p, const char *addr, const char *fmt) 716 { 717 int i; 718 719 for (i = 0; i < 8; i++) { 720 p = pack_hex_byte(p, *addr++); 721 p = pack_hex_byte(p, *addr++); 722 if (fmt[0] == 'I' && i != 7) 723 *p++ = ':'; 724 } 725 *p = '\0'; 726 727 return p; 728 } 729 730 static noinline_for_stack 731 char *ip6_addr_string(char *buf, char *end, const u8 *addr, 732 struct printf_spec spec, const char *fmt) 733 { 734 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 735 736 if (fmt[0] == 'I' && fmt[2] == 'c') 737 ip6_compressed_string(ip6_addr, addr); 738 else 739 ip6_string(ip6_addr, addr, fmt); 740 741 return string(buf, end, ip6_addr, spec); 742 } 743 744 static noinline_for_stack 745 char *ip4_addr_string(char *buf, char *end, const u8 *addr, 746 struct printf_spec spec, const char *fmt) 747 { 748 char ip4_addr[sizeof("255.255.255.255")]; 749 750 ip4_string(ip4_addr, addr, fmt); 751 752 return string(buf, end, ip4_addr, spec); 753 } 754 755 static noinline_for_stack 756 char *uuid_string(char *buf, char *end, const u8 *addr, 757 struct printf_spec spec, const char *fmt) 758 { 759 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")]; 760 char *p = uuid; 761 int i; 762 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15}; 763 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15}; 764 const u8 *index = be; 765 bool uc = false; 766 767 switch (*(++fmt)) { 768 case 'L': 769 uc = true; /* fall-through */ 770 case 'l': 771 index = le; 772 break; 773 case 'B': 774 uc = true; 775 break; 776 } 777 778 for (i = 0; i < 16; i++) { 779 p = pack_hex_byte(p, addr[index[i]]); 780 switch (i) { 781 case 3: 782 case 5: 783 case 7: 784 case 9: 785 *p++ = '-'; 786 break; 787 } 788 } 789 790 *p = 0; 791 792 if (uc) { 793 p = uuid; 794 do { 795 *p = toupper(*p); 796 } while (*(++p)); 797 } 798 799 return string(buf, end, uuid, spec); 800 } 801 802 int kptr_restrict __read_mostly; 803 804 /* 805 * Show a '%p' thing. A kernel extension is that the '%p' is followed 806 * by an extra set of alphanumeric characters that are extended format 807 * specifiers. 808 * 809 * Right now we handle: 810 * 811 * - 'F' For symbolic function descriptor pointers with offset 812 * - 'f' For simple symbolic function names without offset 813 * - 'S' For symbolic direct pointers with offset 814 * - 's' For symbolic direct pointers without offset 815 * - 'B' For backtraced symbolic direct pointers with offset 816 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 817 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 818 * - 'M' For a 6-byte MAC address, it prints the address in the 819 * usual colon-separated hex notation 820 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 821 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 822 * with a dash-separated hex notation 823 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 824 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 825 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 826 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 827 * IPv6 omits the colons (01020304...0f) 828 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 829 * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order 830 * - 'I6c' for IPv6 addresses printed as specified by 831 * http://tools.ietf.org/html/rfc5952 832 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 833 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 834 * Options for %pU are: 835 * b big endian lower case hex (default) 836 * B big endian UPPER case hex 837 * l little endian lower case hex 838 * L little endian UPPER case hex 839 * big endian output byte order is: 840 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 841 * little endian output byte order is: 842 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 843 * - 'V' For a struct va_format which contains a format string * and va_list *, 844 * call vsnprintf(->format, *->va_list). 845 * Implements a "recursive vsnprintf". 846 * Do not use this feature without some mechanism to verify the 847 * correctness of the format string and va_list arguments. 848 * - 'K' For a kernel pointer that should be hidden from unprivileged users 849 * 850 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64 851 * function pointers are really function descriptors, which contain a 852 * pointer to the real address. 853 */ 854 static noinline_for_stack 855 char *pointer(const char *fmt, char *buf, char *end, void *ptr, 856 struct printf_spec spec) 857 { 858 if (!ptr && *fmt != 'K') { 859 /* 860 * Print (null) with the same width as a pointer so it makes 861 * tabular output look nice. 862 */ 863 if (spec.field_width == -1) 864 spec.field_width = 2 * sizeof(void *); 865 return string(buf, end, "(null)", spec); 866 } 867 868 switch (*fmt) { 869 case 'F': 870 case 'f': 871 ptr = dereference_function_descriptor(ptr); 872 /* Fallthrough */ 873 case 'S': 874 case 's': 875 case 'B': 876 return symbol_string(buf, end, ptr, spec, *fmt); 877 case 'R': 878 case 'r': 879 return resource_string(buf, end, ptr, spec, fmt); 880 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 881 case 'm': /* Contiguous: 000102030405 */ 882 /* [mM]F (FDDI, bit reversed) */ 883 return mac_address_string(buf, end, ptr, spec, fmt); 884 case 'I': /* Formatted IP supported 885 * 4: 1.2.3.4 886 * 6: 0001:0203:...:0708 887 * 6c: 1::708 or 1::1.2.3.4 888 */ 889 case 'i': /* Contiguous: 890 * 4: 001.002.003.004 891 * 6: 000102...0f 892 */ 893 switch (fmt[1]) { 894 case '6': 895 return ip6_addr_string(buf, end, ptr, spec, fmt); 896 case '4': 897 return ip4_addr_string(buf, end, ptr, spec, fmt); 898 } 899 break; 900 case 'U': 901 return uuid_string(buf, end, ptr, spec, fmt); 902 case 'V': 903 return buf + vsnprintf(buf, end > buf ? end - buf : 0, 904 ((struct va_format *)ptr)->fmt, 905 *(((struct va_format *)ptr)->va)); 906 case 'K': 907 /* 908 * %pK cannot be used in IRQ context because its test 909 * for CAP_SYSLOG would be meaningless. 910 */ 911 if (in_irq() || in_serving_softirq() || in_nmi()) { 912 if (spec.field_width == -1) 913 spec.field_width = 2 * sizeof(void *); 914 return string(buf, end, "pK-error", spec); 915 } 916 if (!((kptr_restrict == 0) || 917 (kptr_restrict == 1 && 918 has_capability_noaudit(current, CAP_SYSLOG)))) 919 ptr = NULL; 920 break; 921 } 922 spec.flags |= SMALL; 923 if (spec.field_width == -1) { 924 spec.field_width = 2 * sizeof(void *); 925 spec.flags |= ZEROPAD; 926 } 927 spec.base = 16; 928 929 return number(buf, end, (unsigned long) ptr, spec); 930 } 931 932 /* 933 * Helper function to decode printf style format. 934 * Each call decode a token from the format and return the 935 * number of characters read (or likely the delta where it wants 936 * to go on the next call). 937 * The decoded token is returned through the parameters 938 * 939 * 'h', 'l', or 'L' for integer fields 940 * 'z' support added 23/7/1999 S.H. 941 * 'z' changed to 'Z' --davidm 1/25/99 942 * 't' added for ptrdiff_t 943 * 944 * @fmt: the format string 945 * @type of the token returned 946 * @flags: various flags such as +, -, # tokens.. 947 * @field_width: overwritten width 948 * @base: base of the number (octal, hex, ...) 949 * @precision: precision of a number 950 * @qualifier: qualifier of a number (long, size_t, ...) 951 */ 952 static noinline_for_stack 953 int format_decode(const char *fmt, struct printf_spec *spec) 954 { 955 const char *start = fmt; 956 957 /* we finished early by reading the field width */ 958 if (spec->type == FORMAT_TYPE_WIDTH) { 959 if (spec->field_width < 0) { 960 spec->field_width = -spec->field_width; 961 spec->flags |= LEFT; 962 } 963 spec->type = FORMAT_TYPE_NONE; 964 goto precision; 965 } 966 967 /* we finished early by reading the precision */ 968 if (spec->type == FORMAT_TYPE_PRECISION) { 969 if (spec->precision < 0) 970 spec->precision = 0; 971 972 spec->type = FORMAT_TYPE_NONE; 973 goto qualifier; 974 } 975 976 /* By default */ 977 spec->type = FORMAT_TYPE_NONE; 978 979 for (; *fmt ; ++fmt) { 980 if (*fmt == '%') 981 break; 982 } 983 984 /* Return the current non-format string */ 985 if (fmt != start || !*fmt) 986 return fmt - start; 987 988 /* Process flags */ 989 spec->flags = 0; 990 991 while (1) { /* this also skips first '%' */ 992 bool found = true; 993 994 ++fmt; 995 996 switch (*fmt) { 997 case '-': spec->flags |= LEFT; break; 998 case '+': spec->flags |= PLUS; break; 999 case ' ': spec->flags |= SPACE; break; 1000 case '#': spec->flags |= SPECIAL; break; 1001 case '0': spec->flags |= ZEROPAD; break; 1002 default: found = false; 1003 } 1004 1005 if (!found) 1006 break; 1007 } 1008 1009 /* get field width */ 1010 spec->field_width = -1; 1011 1012 if (isdigit(*fmt)) 1013 spec->field_width = skip_atoi(&fmt); 1014 else if (*fmt == '*') { 1015 /* it's the next argument */ 1016 spec->type = FORMAT_TYPE_WIDTH; 1017 return ++fmt - start; 1018 } 1019 1020 precision: 1021 /* get the precision */ 1022 spec->precision = -1; 1023 if (*fmt == '.') { 1024 ++fmt; 1025 if (isdigit(*fmt)) { 1026 spec->precision = skip_atoi(&fmt); 1027 if (spec->precision < 0) 1028 spec->precision = 0; 1029 } else if (*fmt == '*') { 1030 /* it's the next argument */ 1031 spec->type = FORMAT_TYPE_PRECISION; 1032 return ++fmt - start; 1033 } 1034 } 1035 1036 qualifier: 1037 /* get the conversion qualifier */ 1038 spec->qualifier = -1; 1039 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' || 1040 TOLOWER(*fmt) == 'z' || *fmt == 't') { 1041 spec->qualifier = *fmt++; 1042 if (unlikely(spec->qualifier == *fmt)) { 1043 if (spec->qualifier == 'l') { 1044 spec->qualifier = 'L'; 1045 ++fmt; 1046 } else if (spec->qualifier == 'h') { 1047 spec->qualifier = 'H'; 1048 ++fmt; 1049 } 1050 } 1051 } 1052 1053 /* default base */ 1054 spec->base = 10; 1055 switch (*fmt) { 1056 case 'c': 1057 spec->type = FORMAT_TYPE_CHAR; 1058 return ++fmt - start; 1059 1060 case 's': 1061 spec->type = FORMAT_TYPE_STR; 1062 return ++fmt - start; 1063 1064 case 'p': 1065 spec->type = FORMAT_TYPE_PTR; 1066 return fmt - start; 1067 /* skip alnum */ 1068 1069 case 'n': 1070 spec->type = FORMAT_TYPE_NRCHARS; 1071 return ++fmt - start; 1072 1073 case '%': 1074 spec->type = FORMAT_TYPE_PERCENT_CHAR; 1075 return ++fmt - start; 1076 1077 /* integer number formats - set up the flags and "break" */ 1078 case 'o': 1079 spec->base = 8; 1080 break; 1081 1082 case 'x': 1083 spec->flags |= SMALL; 1084 1085 case 'X': 1086 spec->base = 16; 1087 break; 1088 1089 case 'd': 1090 case 'i': 1091 spec->flags |= SIGN; 1092 case 'u': 1093 break; 1094 1095 default: 1096 spec->type = FORMAT_TYPE_INVALID; 1097 return fmt - start; 1098 } 1099 1100 if (spec->qualifier == 'L') 1101 spec->type = FORMAT_TYPE_LONG_LONG; 1102 else if (spec->qualifier == 'l') { 1103 if (spec->flags & SIGN) 1104 spec->type = FORMAT_TYPE_LONG; 1105 else 1106 spec->type = FORMAT_TYPE_ULONG; 1107 } else if (TOLOWER(spec->qualifier) == 'z') { 1108 spec->type = FORMAT_TYPE_SIZE_T; 1109 } else if (spec->qualifier == 't') { 1110 spec->type = FORMAT_TYPE_PTRDIFF; 1111 } else if (spec->qualifier == 'H') { 1112 if (spec->flags & SIGN) 1113 spec->type = FORMAT_TYPE_BYTE; 1114 else 1115 spec->type = FORMAT_TYPE_UBYTE; 1116 } else if (spec->qualifier == 'h') { 1117 if (spec->flags & SIGN) 1118 spec->type = FORMAT_TYPE_SHORT; 1119 else 1120 spec->type = FORMAT_TYPE_USHORT; 1121 } else { 1122 if (spec->flags & SIGN) 1123 spec->type = FORMAT_TYPE_INT; 1124 else 1125 spec->type = FORMAT_TYPE_UINT; 1126 } 1127 1128 return ++fmt - start; 1129 } 1130 1131 /** 1132 * vsnprintf - Format a string and place it in a buffer 1133 * @buf: The buffer to place the result into 1134 * @size: The size of the buffer, including the trailing null space 1135 * @fmt: The format string to use 1136 * @args: Arguments for the format string 1137 * 1138 * This function follows C99 vsnprintf, but has some extensions: 1139 * %pS output the name of a text symbol with offset 1140 * %ps output the name of a text symbol without offset 1141 * %pF output the name of a function pointer with its offset 1142 * %pf output the name of a function pointer without its offset 1143 * %pB output the name of a backtrace symbol with its offset 1144 * %pR output the address range in a struct resource with decoded flags 1145 * %pr output the address range in a struct resource with raw flags 1146 * %pM output a 6-byte MAC address with colons 1147 * %pm output a 6-byte MAC address without colons 1148 * %pI4 print an IPv4 address without leading zeros 1149 * %pi4 print an IPv4 address with leading zeros 1150 * %pI6 print an IPv6 address with colons 1151 * %pi6 print an IPv6 address without colons 1152 * %pI6c print an IPv6 address as specified by 1153 * http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-00 1154 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper 1155 * case. 1156 * %n is ignored 1157 * 1158 * The return value is the number of characters which would 1159 * be generated for the given input, excluding the trailing 1160 * '\0', as per ISO C99. If you want to have the exact 1161 * number of characters written into @buf as return value 1162 * (not including the trailing '\0'), use vscnprintf(). If the 1163 * return is greater than or equal to @size, the resulting 1164 * string is truncated. 1165 * 1166 * If you're not already dealing with a va_list consider using snprintf(). 1167 */ 1168 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) 1169 { 1170 unsigned long long num; 1171 char *str, *end; 1172 struct printf_spec spec = {0}; 1173 1174 /* Reject out-of-range values early. Large positive sizes are 1175 used for unknown buffer sizes. */ 1176 if (WARN_ON_ONCE((int) size < 0)) 1177 return 0; 1178 1179 str = buf; 1180 end = buf + size; 1181 1182 /* Make sure end is always >= buf */ 1183 if (end < buf) { 1184 end = ((void *)-1); 1185 size = end - buf; 1186 } 1187 1188 while (*fmt) { 1189 const char *old_fmt = fmt; 1190 int read = format_decode(fmt, &spec); 1191 1192 fmt += read; 1193 1194 switch (spec.type) { 1195 case FORMAT_TYPE_NONE: { 1196 int copy = read; 1197 if (str < end) { 1198 if (copy > end - str) 1199 copy = end - str; 1200 memcpy(str, old_fmt, copy); 1201 } 1202 str += read; 1203 break; 1204 } 1205 1206 case FORMAT_TYPE_WIDTH: 1207 spec.field_width = va_arg(args, int); 1208 break; 1209 1210 case FORMAT_TYPE_PRECISION: 1211 spec.precision = va_arg(args, int); 1212 break; 1213 1214 case FORMAT_TYPE_CHAR: { 1215 char c; 1216 1217 if (!(spec.flags & LEFT)) { 1218 while (--spec.field_width > 0) { 1219 if (str < end) 1220 *str = ' '; 1221 ++str; 1222 1223 } 1224 } 1225 c = (unsigned char) va_arg(args, int); 1226 if (str < end) 1227 *str = c; 1228 ++str; 1229 while (--spec.field_width > 0) { 1230 if (str < end) 1231 *str = ' '; 1232 ++str; 1233 } 1234 break; 1235 } 1236 1237 case FORMAT_TYPE_STR: 1238 str = string(str, end, va_arg(args, char *), spec); 1239 break; 1240 1241 case FORMAT_TYPE_PTR: 1242 str = pointer(fmt+1, str, end, va_arg(args, void *), 1243 spec); 1244 while (isalnum(*fmt)) 1245 fmt++; 1246 break; 1247 1248 case FORMAT_TYPE_PERCENT_CHAR: 1249 if (str < end) 1250 *str = '%'; 1251 ++str; 1252 break; 1253 1254 case FORMAT_TYPE_INVALID: 1255 if (str < end) 1256 *str = '%'; 1257 ++str; 1258 break; 1259 1260 case FORMAT_TYPE_NRCHARS: { 1261 u8 qualifier = spec.qualifier; 1262 1263 if (qualifier == 'l') { 1264 long *ip = va_arg(args, long *); 1265 *ip = (str - buf); 1266 } else if (TOLOWER(qualifier) == 'z') { 1267 size_t *ip = va_arg(args, size_t *); 1268 *ip = (str - buf); 1269 } else { 1270 int *ip = va_arg(args, int *); 1271 *ip = (str - buf); 1272 } 1273 break; 1274 } 1275 1276 default: 1277 switch (spec.type) { 1278 case FORMAT_TYPE_LONG_LONG: 1279 num = va_arg(args, long long); 1280 break; 1281 case FORMAT_TYPE_ULONG: 1282 num = va_arg(args, unsigned long); 1283 break; 1284 case FORMAT_TYPE_LONG: 1285 num = va_arg(args, long); 1286 break; 1287 case FORMAT_TYPE_SIZE_T: 1288 num = va_arg(args, size_t); 1289 break; 1290 case FORMAT_TYPE_PTRDIFF: 1291 num = va_arg(args, ptrdiff_t); 1292 break; 1293 case FORMAT_TYPE_UBYTE: 1294 num = (unsigned char) va_arg(args, int); 1295 break; 1296 case FORMAT_TYPE_BYTE: 1297 num = (signed char) va_arg(args, int); 1298 break; 1299 case FORMAT_TYPE_USHORT: 1300 num = (unsigned short) va_arg(args, int); 1301 break; 1302 case FORMAT_TYPE_SHORT: 1303 num = (short) va_arg(args, int); 1304 break; 1305 case FORMAT_TYPE_INT: 1306 num = (int) va_arg(args, int); 1307 break; 1308 default: 1309 num = va_arg(args, unsigned int); 1310 } 1311 1312 str = number(str, end, num, spec); 1313 } 1314 } 1315 1316 if (size > 0) { 1317 if (str < end) 1318 *str = '\0'; 1319 else 1320 end[-1] = '\0'; 1321 } 1322 1323 /* the trailing null byte doesn't count towards the total */ 1324 return str-buf; 1325 1326 } 1327 EXPORT_SYMBOL(vsnprintf); 1328 1329 /** 1330 * vscnprintf - Format a string and place it in a buffer 1331 * @buf: The buffer to place the result into 1332 * @size: The size of the buffer, including the trailing null space 1333 * @fmt: The format string to use 1334 * @args: Arguments for the format string 1335 * 1336 * The return value is the number of characters which have been written into 1337 * the @buf not including the trailing '\0'. If @size is == 0 the function 1338 * returns 0. 1339 * 1340 * If you're not already dealing with a va_list consider using scnprintf(). 1341 * 1342 * See the vsnprintf() documentation for format string extensions over C99. 1343 */ 1344 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 1345 { 1346 int i; 1347 1348 i = vsnprintf(buf, size, fmt, args); 1349 1350 if (likely(i < size)) 1351 return i; 1352 if (size != 0) 1353 return size - 1; 1354 return 0; 1355 } 1356 EXPORT_SYMBOL(vscnprintf); 1357 1358 /** 1359 * snprintf - Format a string and place it in a buffer 1360 * @buf: The buffer to place the result into 1361 * @size: The size of the buffer, including the trailing null space 1362 * @fmt: The format string to use 1363 * @...: Arguments for the format string 1364 * 1365 * The return value is the number of characters which would be 1366 * generated for the given input, excluding the trailing null, 1367 * as per ISO C99. If the return is greater than or equal to 1368 * @size, the resulting string is truncated. 1369 * 1370 * See the vsnprintf() documentation for format string extensions over C99. 1371 */ 1372 int snprintf(char *buf, size_t size, const char *fmt, ...) 1373 { 1374 va_list args; 1375 int i; 1376 1377 va_start(args, fmt); 1378 i = vsnprintf(buf, size, fmt, args); 1379 va_end(args); 1380 1381 return i; 1382 } 1383 EXPORT_SYMBOL(snprintf); 1384 1385 /** 1386 * scnprintf - Format a string and place it in a buffer 1387 * @buf: The buffer to place the result into 1388 * @size: The size of the buffer, including the trailing null space 1389 * @fmt: The format string to use 1390 * @...: Arguments for the format string 1391 * 1392 * The return value is the number of characters written into @buf not including 1393 * the trailing '\0'. If @size is == 0 the function returns 0. 1394 */ 1395 1396 int scnprintf(char *buf, size_t size, const char *fmt, ...) 1397 { 1398 va_list args; 1399 int i; 1400 1401 va_start(args, fmt); 1402 i = vscnprintf(buf, size, fmt, args); 1403 va_end(args); 1404 1405 return i; 1406 } 1407 EXPORT_SYMBOL(scnprintf); 1408 1409 /** 1410 * vsprintf - Format a string and place it in a buffer 1411 * @buf: The buffer to place the result into 1412 * @fmt: The format string to use 1413 * @args: Arguments for the format string 1414 * 1415 * The function returns the number of characters written 1416 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid 1417 * buffer overflows. 1418 * 1419 * If you're not already dealing with a va_list consider using sprintf(). 1420 * 1421 * See the vsnprintf() documentation for format string extensions over C99. 1422 */ 1423 int vsprintf(char *buf, const char *fmt, va_list args) 1424 { 1425 return vsnprintf(buf, INT_MAX, fmt, args); 1426 } 1427 EXPORT_SYMBOL(vsprintf); 1428 1429 /** 1430 * sprintf - Format a string and place it in a buffer 1431 * @buf: The buffer to place the result into 1432 * @fmt: The format string to use 1433 * @...: Arguments for the format string 1434 * 1435 * The function returns the number of characters written 1436 * into @buf. Use snprintf() or scnprintf() in order to avoid 1437 * buffer overflows. 1438 * 1439 * See the vsnprintf() documentation for format string extensions over C99. 1440 */ 1441 int sprintf(char *buf, const char *fmt, ...) 1442 { 1443 va_list args; 1444 int i; 1445 1446 va_start(args, fmt); 1447 i = vsnprintf(buf, INT_MAX, fmt, args); 1448 va_end(args); 1449 1450 return i; 1451 } 1452 EXPORT_SYMBOL(sprintf); 1453 1454 #ifdef CONFIG_BINARY_PRINTF 1455 /* 1456 * bprintf service: 1457 * vbin_printf() - VA arguments to binary data 1458 * bstr_printf() - Binary data to text string 1459 */ 1460 1461 /** 1462 * vbin_printf - Parse a format string and place args' binary value in a buffer 1463 * @bin_buf: The buffer to place args' binary value 1464 * @size: The size of the buffer(by words(32bits), not characters) 1465 * @fmt: The format string to use 1466 * @args: Arguments for the format string 1467 * 1468 * The format follows C99 vsnprintf, except %n is ignored, and its argument 1469 * is skiped. 1470 * 1471 * The return value is the number of words(32bits) which would be generated for 1472 * the given input. 1473 * 1474 * NOTE: 1475 * If the return value is greater than @size, the resulting bin_buf is NOT 1476 * valid for bstr_printf(). 1477 */ 1478 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args) 1479 { 1480 struct printf_spec spec = {0}; 1481 char *str, *end; 1482 1483 str = (char *)bin_buf; 1484 end = (char *)(bin_buf + size); 1485 1486 #define save_arg(type) \ 1487 do { \ 1488 if (sizeof(type) == 8) { \ 1489 unsigned long long value; \ 1490 str = PTR_ALIGN(str, sizeof(u32)); \ 1491 value = va_arg(args, unsigned long long); \ 1492 if (str + sizeof(type) <= end) { \ 1493 *(u32 *)str = *(u32 *)&value; \ 1494 *(u32 *)(str + 4) = *((u32 *)&value + 1); \ 1495 } \ 1496 } else { \ 1497 unsigned long value; \ 1498 str = PTR_ALIGN(str, sizeof(type)); \ 1499 value = va_arg(args, int); \ 1500 if (str + sizeof(type) <= end) \ 1501 *(typeof(type) *)str = (type)value; \ 1502 } \ 1503 str += sizeof(type); \ 1504 } while (0) 1505 1506 while (*fmt) { 1507 int read = format_decode(fmt, &spec); 1508 1509 fmt += read; 1510 1511 switch (spec.type) { 1512 case FORMAT_TYPE_NONE: 1513 case FORMAT_TYPE_INVALID: 1514 case FORMAT_TYPE_PERCENT_CHAR: 1515 break; 1516 1517 case FORMAT_TYPE_WIDTH: 1518 case FORMAT_TYPE_PRECISION: 1519 save_arg(int); 1520 break; 1521 1522 case FORMAT_TYPE_CHAR: 1523 save_arg(char); 1524 break; 1525 1526 case FORMAT_TYPE_STR: { 1527 const char *save_str = va_arg(args, char *); 1528 size_t len; 1529 1530 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE 1531 || (unsigned long)save_str < PAGE_SIZE) 1532 save_str = "(null)"; 1533 len = strlen(save_str) + 1; 1534 if (str + len < end) 1535 memcpy(str, save_str, len); 1536 str += len; 1537 break; 1538 } 1539 1540 case FORMAT_TYPE_PTR: 1541 save_arg(void *); 1542 /* skip all alphanumeric pointer suffixes */ 1543 while (isalnum(*fmt)) 1544 fmt++; 1545 break; 1546 1547 case FORMAT_TYPE_NRCHARS: { 1548 /* skip %n 's argument */ 1549 u8 qualifier = spec.qualifier; 1550 void *skip_arg; 1551 if (qualifier == 'l') 1552 skip_arg = va_arg(args, long *); 1553 else if (TOLOWER(qualifier) == 'z') 1554 skip_arg = va_arg(args, size_t *); 1555 else 1556 skip_arg = va_arg(args, int *); 1557 break; 1558 } 1559 1560 default: 1561 switch (spec.type) { 1562 1563 case FORMAT_TYPE_LONG_LONG: 1564 save_arg(long long); 1565 break; 1566 case FORMAT_TYPE_ULONG: 1567 case FORMAT_TYPE_LONG: 1568 save_arg(unsigned long); 1569 break; 1570 case FORMAT_TYPE_SIZE_T: 1571 save_arg(size_t); 1572 break; 1573 case FORMAT_TYPE_PTRDIFF: 1574 save_arg(ptrdiff_t); 1575 break; 1576 case FORMAT_TYPE_UBYTE: 1577 case FORMAT_TYPE_BYTE: 1578 save_arg(char); 1579 break; 1580 case FORMAT_TYPE_USHORT: 1581 case FORMAT_TYPE_SHORT: 1582 save_arg(short); 1583 break; 1584 default: 1585 save_arg(int); 1586 } 1587 } 1588 } 1589 1590 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 1591 #undef save_arg 1592 } 1593 EXPORT_SYMBOL_GPL(vbin_printf); 1594 1595 /** 1596 * bstr_printf - Format a string from binary arguments and place it in a buffer 1597 * @buf: The buffer to place the result into 1598 * @size: The size of the buffer, including the trailing null space 1599 * @fmt: The format string to use 1600 * @bin_buf: Binary arguments for the format string 1601 * 1602 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 1603 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 1604 * a binary buffer that generated by vbin_printf. 1605 * 1606 * The format follows C99 vsnprintf, but has some extensions: 1607 * see vsnprintf comment for details. 1608 * 1609 * The return value is the number of characters which would 1610 * be generated for the given input, excluding the trailing 1611 * '\0', as per ISO C99. If you want to have the exact 1612 * number of characters written into @buf as return value 1613 * (not including the trailing '\0'), use vscnprintf(). If the 1614 * return is greater than or equal to @size, the resulting 1615 * string is truncated. 1616 */ 1617 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) 1618 { 1619 struct printf_spec spec = {0}; 1620 char *str, *end; 1621 const char *args = (const char *)bin_buf; 1622 1623 if (WARN_ON_ONCE((int) size < 0)) 1624 return 0; 1625 1626 str = buf; 1627 end = buf + size; 1628 1629 #define get_arg(type) \ 1630 ({ \ 1631 typeof(type) value; \ 1632 if (sizeof(type) == 8) { \ 1633 args = PTR_ALIGN(args, sizeof(u32)); \ 1634 *(u32 *)&value = *(u32 *)args; \ 1635 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 1636 } else { \ 1637 args = PTR_ALIGN(args, sizeof(type)); \ 1638 value = *(typeof(type) *)args; \ 1639 } \ 1640 args += sizeof(type); \ 1641 value; \ 1642 }) 1643 1644 /* Make sure end is always >= buf */ 1645 if (end < buf) { 1646 end = ((void *)-1); 1647 size = end - buf; 1648 } 1649 1650 while (*fmt) { 1651 const char *old_fmt = fmt; 1652 int read = format_decode(fmt, &spec); 1653 1654 fmt += read; 1655 1656 switch (spec.type) { 1657 case FORMAT_TYPE_NONE: { 1658 int copy = read; 1659 if (str < end) { 1660 if (copy > end - str) 1661 copy = end - str; 1662 memcpy(str, old_fmt, copy); 1663 } 1664 str += read; 1665 break; 1666 } 1667 1668 case FORMAT_TYPE_WIDTH: 1669 spec.field_width = get_arg(int); 1670 break; 1671 1672 case FORMAT_TYPE_PRECISION: 1673 spec.precision = get_arg(int); 1674 break; 1675 1676 case FORMAT_TYPE_CHAR: { 1677 char c; 1678 1679 if (!(spec.flags & LEFT)) { 1680 while (--spec.field_width > 0) { 1681 if (str < end) 1682 *str = ' '; 1683 ++str; 1684 } 1685 } 1686 c = (unsigned char) get_arg(char); 1687 if (str < end) 1688 *str = c; 1689 ++str; 1690 while (--spec.field_width > 0) { 1691 if (str < end) 1692 *str = ' '; 1693 ++str; 1694 } 1695 break; 1696 } 1697 1698 case FORMAT_TYPE_STR: { 1699 const char *str_arg = args; 1700 args += strlen(str_arg) + 1; 1701 str = string(str, end, (char *)str_arg, spec); 1702 break; 1703 } 1704 1705 case FORMAT_TYPE_PTR: 1706 str = pointer(fmt+1, str, end, get_arg(void *), spec); 1707 while (isalnum(*fmt)) 1708 fmt++; 1709 break; 1710 1711 case FORMAT_TYPE_PERCENT_CHAR: 1712 case FORMAT_TYPE_INVALID: 1713 if (str < end) 1714 *str = '%'; 1715 ++str; 1716 break; 1717 1718 case FORMAT_TYPE_NRCHARS: 1719 /* skip */ 1720 break; 1721 1722 default: { 1723 unsigned long long num; 1724 1725 switch (spec.type) { 1726 1727 case FORMAT_TYPE_LONG_LONG: 1728 num = get_arg(long long); 1729 break; 1730 case FORMAT_TYPE_ULONG: 1731 case FORMAT_TYPE_LONG: 1732 num = get_arg(unsigned long); 1733 break; 1734 case FORMAT_TYPE_SIZE_T: 1735 num = get_arg(size_t); 1736 break; 1737 case FORMAT_TYPE_PTRDIFF: 1738 num = get_arg(ptrdiff_t); 1739 break; 1740 case FORMAT_TYPE_UBYTE: 1741 num = get_arg(unsigned char); 1742 break; 1743 case FORMAT_TYPE_BYTE: 1744 num = get_arg(signed char); 1745 break; 1746 case FORMAT_TYPE_USHORT: 1747 num = get_arg(unsigned short); 1748 break; 1749 case FORMAT_TYPE_SHORT: 1750 num = get_arg(short); 1751 break; 1752 case FORMAT_TYPE_UINT: 1753 num = get_arg(unsigned int); 1754 break; 1755 default: 1756 num = get_arg(int); 1757 } 1758 1759 str = number(str, end, num, spec); 1760 } /* default: */ 1761 } /* switch(spec.type) */ 1762 } /* while(*fmt) */ 1763 1764 if (size > 0) { 1765 if (str < end) 1766 *str = '\0'; 1767 else 1768 end[-1] = '\0'; 1769 } 1770 1771 #undef get_arg 1772 1773 /* the trailing null byte doesn't count towards the total */ 1774 return str - buf; 1775 } 1776 EXPORT_SYMBOL_GPL(bstr_printf); 1777 1778 /** 1779 * bprintf - Parse a format string and place args' binary value in a buffer 1780 * @bin_buf: The buffer to place args' binary value 1781 * @size: The size of the buffer(by words(32bits), not characters) 1782 * @fmt: The format string to use 1783 * @...: Arguments for the format string 1784 * 1785 * The function returns the number of words(u32) written 1786 * into @bin_buf. 1787 */ 1788 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) 1789 { 1790 va_list args; 1791 int ret; 1792 1793 va_start(args, fmt); 1794 ret = vbin_printf(bin_buf, size, fmt, args); 1795 va_end(args); 1796 1797 return ret; 1798 } 1799 EXPORT_SYMBOL_GPL(bprintf); 1800 1801 #endif /* CONFIG_BINARY_PRINTF */ 1802 1803 /** 1804 * vsscanf - Unformat a buffer into a list of arguments 1805 * @buf: input buffer 1806 * @fmt: format of buffer 1807 * @args: arguments 1808 */ 1809 int vsscanf(const char *buf, const char *fmt, va_list args) 1810 { 1811 const char *str = buf; 1812 char *next; 1813 char digit; 1814 int num = 0; 1815 u8 qualifier; 1816 u8 base; 1817 s16 field_width; 1818 bool is_sign; 1819 1820 while (*fmt && *str) { 1821 /* skip any white space in format */ 1822 /* white space in format matchs any amount of 1823 * white space, including none, in the input. 1824 */ 1825 if (isspace(*fmt)) { 1826 fmt = skip_spaces(++fmt); 1827 str = skip_spaces(str); 1828 } 1829 1830 /* anything that is not a conversion must match exactly */ 1831 if (*fmt != '%' && *fmt) { 1832 if (*fmt++ != *str++) 1833 break; 1834 continue; 1835 } 1836 1837 if (!*fmt) 1838 break; 1839 ++fmt; 1840 1841 /* skip this conversion. 1842 * advance both strings to next white space 1843 */ 1844 if (*fmt == '*') { 1845 while (!isspace(*fmt) && *fmt != '%' && *fmt) 1846 fmt++; 1847 while (!isspace(*str) && *str) 1848 str++; 1849 continue; 1850 } 1851 1852 /* get field width */ 1853 field_width = -1; 1854 if (isdigit(*fmt)) 1855 field_width = skip_atoi(&fmt); 1856 1857 /* get conversion qualifier */ 1858 qualifier = -1; 1859 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' || 1860 TOLOWER(*fmt) == 'z') { 1861 qualifier = *fmt++; 1862 if (unlikely(qualifier == *fmt)) { 1863 if (qualifier == 'h') { 1864 qualifier = 'H'; 1865 fmt++; 1866 } else if (qualifier == 'l') { 1867 qualifier = 'L'; 1868 fmt++; 1869 } 1870 } 1871 } 1872 1873 if (!*fmt || !*str) 1874 break; 1875 1876 base = 10; 1877 is_sign = 0; 1878 1879 switch (*fmt++) { 1880 case 'c': 1881 { 1882 char *s = (char *)va_arg(args, char*); 1883 if (field_width == -1) 1884 field_width = 1; 1885 do { 1886 *s++ = *str++; 1887 } while (--field_width > 0 && *str); 1888 num++; 1889 } 1890 continue; 1891 case 's': 1892 { 1893 char *s = (char *)va_arg(args, char *); 1894 if (field_width == -1) 1895 field_width = SHRT_MAX; 1896 /* first, skip leading white space in buffer */ 1897 str = skip_spaces(str); 1898 1899 /* now copy until next white space */ 1900 while (*str && !isspace(*str) && field_width--) 1901 *s++ = *str++; 1902 *s = '\0'; 1903 num++; 1904 } 1905 continue; 1906 case 'n': 1907 /* return number of characters read so far */ 1908 { 1909 int *i = (int *)va_arg(args, int*); 1910 *i = str - buf; 1911 } 1912 continue; 1913 case 'o': 1914 base = 8; 1915 break; 1916 case 'x': 1917 case 'X': 1918 base = 16; 1919 break; 1920 case 'i': 1921 base = 0; 1922 case 'd': 1923 is_sign = 1; 1924 case 'u': 1925 break; 1926 case '%': 1927 /* looking for '%' in str */ 1928 if (*str++ != '%') 1929 return num; 1930 continue; 1931 default: 1932 /* invalid format; stop here */ 1933 return num; 1934 } 1935 1936 /* have some sort of integer conversion. 1937 * first, skip white space in buffer. 1938 */ 1939 str = skip_spaces(str); 1940 1941 digit = *str; 1942 if (is_sign && digit == '-') 1943 digit = *(str + 1); 1944 1945 if (!digit 1946 || (base == 16 && !isxdigit(digit)) 1947 || (base == 10 && !isdigit(digit)) 1948 || (base == 8 && (!isdigit(digit) || digit > '7')) 1949 || (base == 0 && !isdigit(digit))) 1950 break; 1951 1952 switch (qualifier) { 1953 case 'H': /* that's 'hh' in format */ 1954 if (is_sign) { 1955 signed char *s = (signed char *)va_arg(args, signed char *); 1956 *s = (signed char)simple_strtol(str, &next, base); 1957 } else { 1958 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *); 1959 *s = (unsigned char)simple_strtoul(str, &next, base); 1960 } 1961 break; 1962 case 'h': 1963 if (is_sign) { 1964 short *s = (short *)va_arg(args, short *); 1965 *s = (short)simple_strtol(str, &next, base); 1966 } else { 1967 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *); 1968 *s = (unsigned short)simple_strtoul(str, &next, base); 1969 } 1970 break; 1971 case 'l': 1972 if (is_sign) { 1973 long *l = (long *)va_arg(args, long *); 1974 *l = simple_strtol(str, &next, base); 1975 } else { 1976 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *); 1977 *l = simple_strtoul(str, &next, base); 1978 } 1979 break; 1980 case 'L': 1981 if (is_sign) { 1982 long long *l = (long long *)va_arg(args, long long *); 1983 *l = simple_strtoll(str, &next, base); 1984 } else { 1985 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *); 1986 *l = simple_strtoull(str, &next, base); 1987 } 1988 break; 1989 case 'Z': 1990 case 'z': 1991 { 1992 size_t *s = (size_t *)va_arg(args, size_t *); 1993 *s = (size_t)simple_strtoul(str, &next, base); 1994 } 1995 break; 1996 default: 1997 if (is_sign) { 1998 int *i = (int *)va_arg(args, int *); 1999 *i = (int)simple_strtol(str, &next, base); 2000 } else { 2001 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*); 2002 *i = (unsigned int)simple_strtoul(str, &next, base); 2003 } 2004 break; 2005 } 2006 num++; 2007 2008 if (!next) 2009 break; 2010 str = next; 2011 } 2012 2013 /* 2014 * Now we've come all the way through so either the input string or the 2015 * format ended. In the former case, there can be a %n at the current 2016 * position in the format that needs to be filled. 2017 */ 2018 if (*fmt == '%' && *(fmt + 1) == 'n') { 2019 int *p = (int *)va_arg(args, int *); 2020 *p = str - buf; 2021 } 2022 2023 return num; 2024 } 2025 EXPORT_SYMBOL(vsscanf); 2026 2027 /** 2028 * sscanf - Unformat a buffer into a list of arguments 2029 * @buf: input buffer 2030 * @fmt: formatting of buffer 2031 * @...: resulting arguments 2032 */ 2033 int sscanf(const char *buf, const char *fmt, ...) 2034 { 2035 va_list args; 2036 int i; 2037 2038 va_start(args, fmt); 2039 i = vsscanf(buf, fmt, args); 2040 va_end(args); 2041 2042 return i; 2043 } 2044 EXPORT_SYMBOL(sscanf); 2045