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