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 #include "kstrtox.h" 35 36 /** 37 * simple_strtoull - convert a string to an unsigned long long 38 * @cp: The start of the string 39 * @endp: A pointer to the end of the parsed string will be placed here 40 * @base: The number base to use 41 */ 42 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) 43 { 44 unsigned long long result; 45 unsigned int rv; 46 47 cp = _parse_integer_fixup_radix(cp, &base); 48 rv = _parse_integer(cp, base, &result); 49 /* FIXME */ 50 cp += (rv & ~KSTRTOX_OVERFLOW); 51 52 if (endp) 53 *endp = (char *)cp; 54 55 return result; 56 } 57 EXPORT_SYMBOL(simple_strtoull); 58 59 /** 60 * simple_strtoul - convert a string to an unsigned long 61 * @cp: The start of the string 62 * @endp: A pointer to the end of the parsed string will be placed here 63 * @base: The number base to use 64 */ 65 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) 66 { 67 return simple_strtoull(cp, endp, base); 68 } 69 EXPORT_SYMBOL(simple_strtoul); 70 71 /** 72 * simple_strtol - convert a string to a signed long 73 * @cp: The start of the string 74 * @endp: A pointer to the end of the parsed string will be placed here 75 * @base: The number base to use 76 */ 77 long simple_strtol(const char *cp, char **endp, unsigned int base) 78 { 79 if (*cp == '-') 80 return -simple_strtoul(cp + 1, endp, base); 81 82 return simple_strtoul(cp, endp, base); 83 } 84 EXPORT_SYMBOL(simple_strtol); 85 86 /** 87 * simple_strtoll - convert a string to a signed long long 88 * @cp: The start of the string 89 * @endp: A pointer to the end of the parsed string will be placed here 90 * @base: The number base to use 91 */ 92 long long simple_strtoll(const char *cp, char **endp, unsigned int base) 93 { 94 if (*cp == '-') 95 return -simple_strtoull(cp + 1, endp, base); 96 97 return simple_strtoull(cp, endp, base); 98 } 99 EXPORT_SYMBOL(simple_strtoll); 100 101 static noinline_for_stack 102 int skip_atoi(const char **s) 103 { 104 int i = 0; 105 106 while (isdigit(**s)) 107 i = i*10 + *((*s)++) - '0'; 108 109 return i; 110 } 111 112 /* Decimal conversion is by far the most typical, and is used 113 * for /proc and /sys data. This directly impacts e.g. top performance 114 * with many processes running. We optimize it for speed 115 * using code from 116 * http://www.cs.uiowa.edu/~jones/bcd/decimal.html 117 * (with permission from the author, Douglas W. Jones). */ 118 119 /* Formats correctly any integer in [0,99999]. 120 * Outputs from one to five digits depending on input. 121 * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */ 122 static noinline_for_stack 123 char *put_dec_trunc(char *buf, unsigned q) 124 { 125 unsigned d3, d2, d1, d0; 126 d1 = (q>>4) & 0xf; 127 d2 = (q>>8) & 0xf; 128 d3 = (q>>12); 129 130 d0 = 6*(d3 + d2 + d1) + (q & 0xf); 131 q = (d0 * 0xcd) >> 11; 132 d0 = d0 - 10*q; 133 *buf++ = d0 + '0'; /* least significant digit */ 134 d1 = q + 9*d3 + 5*d2 + d1; 135 if (d1 != 0) { 136 q = (d1 * 0xcd) >> 11; 137 d1 = d1 - 10*q; 138 *buf++ = d1 + '0'; /* next digit */ 139 140 d2 = q + 2*d2; 141 if ((d2 != 0) || (d3 != 0)) { 142 q = (d2 * 0xd) >> 7; 143 d2 = d2 - 10*q; 144 *buf++ = d2 + '0'; /* next digit */ 145 146 d3 = q + 4*d3; 147 if (d3 != 0) { 148 q = (d3 * 0xcd) >> 11; 149 d3 = d3 - 10*q; 150 *buf++ = d3 + '0'; /* next digit */ 151 if (q != 0) 152 *buf++ = q + '0'; /* most sign. digit */ 153 } 154 } 155 } 156 157 return buf; 158 } 159 /* Same with if's removed. Always emits five digits */ 160 static noinline_for_stack 161 char *put_dec_full(char *buf, unsigned q) 162 { 163 /* BTW, if q is in [0,9999], 8-bit ints will be enough, */ 164 /* but anyway, gcc produces better code with full-sized ints */ 165 unsigned d3, d2, d1, d0; 166 d1 = (q>>4) & 0xf; 167 d2 = (q>>8) & 0xf; 168 d3 = (q>>12); 169 170 /* 171 * Possible ways to approx. divide by 10 172 * gcc -O2 replaces multiply with shifts and adds 173 * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386) 174 * (x * 0x67) >> 10: 1100111 175 * (x * 0x34) >> 9: 110100 - same 176 * (x * 0x1a) >> 8: 11010 - same 177 * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386) 178 */ 179 d0 = 6*(d3 + d2 + d1) + (q & 0xf); 180 q = (d0 * 0xcd) >> 11; 181 d0 = d0 - 10*q; 182 *buf++ = d0 + '0'; 183 d1 = q + 9*d3 + 5*d2 + d1; 184 q = (d1 * 0xcd) >> 11; 185 d1 = d1 - 10*q; 186 *buf++ = d1 + '0'; 187 188 d2 = q + 2*d2; 189 q = (d2 * 0xd) >> 7; 190 d2 = d2 - 10*q; 191 *buf++ = d2 + '0'; 192 193 d3 = q + 4*d3; 194 q = (d3 * 0xcd) >> 11; /* - shorter code */ 195 /* q = (d3 * 0x67) >> 10; - would also work */ 196 d3 = d3 - 10*q; 197 *buf++ = d3 + '0'; 198 *buf++ = q + '0'; 199 200 return buf; 201 } 202 /* No inlining helps gcc to use registers better */ 203 static noinline_for_stack 204 char *put_dec(char *buf, unsigned long long num) 205 { 206 while (1) { 207 unsigned rem; 208 if (num < 100000) 209 return put_dec_trunc(buf, num); 210 rem = do_div(num, 100000); 211 buf = put_dec_full(buf, rem); 212 } 213 } 214 215 #define ZEROPAD 1 /* pad with zero */ 216 #define SIGN 2 /* unsigned/signed long */ 217 #define PLUS 4 /* show plus */ 218 #define SPACE 8 /* space if plus */ 219 #define LEFT 16 /* left justified */ 220 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */ 221 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */ 222 223 enum format_type { 224 FORMAT_TYPE_NONE, /* Just a string part */ 225 FORMAT_TYPE_WIDTH, 226 FORMAT_TYPE_PRECISION, 227 FORMAT_TYPE_CHAR, 228 FORMAT_TYPE_STR, 229 FORMAT_TYPE_PTR, 230 FORMAT_TYPE_PERCENT_CHAR, 231 FORMAT_TYPE_INVALID, 232 FORMAT_TYPE_LONG_LONG, 233 FORMAT_TYPE_ULONG, 234 FORMAT_TYPE_LONG, 235 FORMAT_TYPE_UBYTE, 236 FORMAT_TYPE_BYTE, 237 FORMAT_TYPE_USHORT, 238 FORMAT_TYPE_SHORT, 239 FORMAT_TYPE_UINT, 240 FORMAT_TYPE_INT, 241 FORMAT_TYPE_NRCHARS, 242 FORMAT_TYPE_SIZE_T, 243 FORMAT_TYPE_PTRDIFF 244 }; 245 246 struct printf_spec { 247 u8 type; /* format_type enum */ 248 u8 flags; /* flags to number() */ 249 u8 base; /* number base, 8, 10 or 16 only */ 250 u8 qualifier; /* number qualifier, one of 'hHlLtzZ' */ 251 s16 field_width; /* width of output field */ 252 s16 precision; /* # of digits/chars */ 253 }; 254 255 static noinline_for_stack 256 char *number(char *buf, char *end, unsigned long long num, 257 struct printf_spec spec) 258 { 259 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */ 260 static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */ 261 262 char tmp[66]; 263 char sign; 264 char locase; 265 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10); 266 int i; 267 268 /* locase = 0 or 0x20. ORing digits or letters with 'locase' 269 * produces same digits or (maybe lowercased) letters */ 270 locase = (spec.flags & SMALL); 271 if (spec.flags & LEFT) 272 spec.flags &= ~ZEROPAD; 273 sign = 0; 274 if (spec.flags & SIGN) { 275 if ((signed long long)num < 0) { 276 sign = '-'; 277 num = -(signed long long)num; 278 spec.field_width--; 279 } else if (spec.flags & PLUS) { 280 sign = '+'; 281 spec.field_width--; 282 } else if (spec.flags & SPACE) { 283 sign = ' '; 284 spec.field_width--; 285 } 286 } 287 if (need_pfx) { 288 spec.field_width--; 289 if (spec.base == 16) 290 spec.field_width--; 291 } 292 293 /* generate full string in tmp[], in reverse order */ 294 i = 0; 295 if (num == 0) 296 tmp[i++] = '0'; 297 /* Generic code, for any base: 298 else do { 299 tmp[i++] = (digits[do_div(num,base)] | locase); 300 } while (num != 0); 301 */ 302 else if (spec.base != 10) { /* 8 or 16 */ 303 int mask = spec.base - 1; 304 int shift = 3; 305 306 if (spec.base == 16) 307 shift = 4; 308 do { 309 tmp[i++] = (digits[((unsigned char)num) & mask] | locase); 310 num >>= shift; 311 } while (num); 312 } else { /* base 10 */ 313 i = put_dec(tmp, num) - tmp; 314 } 315 316 /* printing 100 using %2d gives "100", not "00" */ 317 if (i > spec.precision) 318 spec.precision = i; 319 /* leading space padding */ 320 spec.field_width -= spec.precision; 321 if (!(spec.flags & (ZEROPAD+LEFT))) { 322 while (--spec.field_width >= 0) { 323 if (buf < end) 324 *buf = ' '; 325 ++buf; 326 } 327 } 328 /* sign */ 329 if (sign) { 330 if (buf < end) 331 *buf = sign; 332 ++buf; 333 } 334 /* "0x" / "0" prefix */ 335 if (need_pfx) { 336 if (buf < end) 337 *buf = '0'; 338 ++buf; 339 if (spec.base == 16) { 340 if (buf < end) 341 *buf = ('X' | locase); 342 ++buf; 343 } 344 } 345 /* zero or space padding */ 346 if (!(spec.flags & LEFT)) { 347 char c = (spec.flags & ZEROPAD) ? '0' : ' '; 348 while (--spec.field_width >= 0) { 349 if (buf < end) 350 *buf = c; 351 ++buf; 352 } 353 } 354 /* hmm even more zero padding? */ 355 while (i <= --spec.precision) { 356 if (buf < end) 357 *buf = '0'; 358 ++buf; 359 } 360 /* actual digits of result */ 361 while (--i >= 0) { 362 if (buf < end) 363 *buf = tmp[i]; 364 ++buf; 365 } 366 /* trailing space padding */ 367 while (--spec.field_width >= 0) { 368 if (buf < end) 369 *buf = ' '; 370 ++buf; 371 } 372 373 return buf; 374 } 375 376 static noinline_for_stack 377 char *string(char *buf, char *end, const char *s, struct printf_spec spec) 378 { 379 int len, i; 380 381 if ((unsigned long)s < PAGE_SIZE) 382 s = "(null)"; 383 384 len = strnlen(s, spec.precision); 385 386 if (!(spec.flags & LEFT)) { 387 while (len < spec.field_width--) { 388 if (buf < end) 389 *buf = ' '; 390 ++buf; 391 } 392 } 393 for (i = 0; i < len; ++i) { 394 if (buf < end) 395 *buf = *s; 396 ++buf; ++s; 397 } 398 while (len < spec.field_width--) { 399 if (buf < end) 400 *buf = ' '; 401 ++buf; 402 } 403 404 return buf; 405 } 406 407 static noinline_for_stack 408 char *symbol_string(char *buf, char *end, void *ptr, 409 struct printf_spec spec, char ext) 410 { 411 unsigned long value = (unsigned long) ptr; 412 #ifdef CONFIG_KALLSYMS 413 char sym[KSYM_SYMBOL_LEN]; 414 if (ext == 'B') 415 sprint_backtrace(sym, value); 416 else if (ext != 'f' && ext != 's') 417 sprint_symbol(sym, value); 418 else 419 kallsyms_lookup(value, NULL, NULL, NULL, sym); 420 421 return string(buf, end, sym, spec); 422 #else 423 spec.field_width = 2 * sizeof(void *); 424 spec.flags |= SPECIAL | SMALL | ZEROPAD; 425 spec.base = 16; 426 427 return number(buf, end, value, spec); 428 #endif 429 } 430 431 static noinline_for_stack 432 char *resource_string(char *buf, char *end, struct resource *res, 433 struct printf_spec spec, const char *fmt) 434 { 435 #ifndef IO_RSRC_PRINTK_SIZE 436 #define IO_RSRC_PRINTK_SIZE 6 437 #endif 438 439 #ifndef MEM_RSRC_PRINTK_SIZE 440 #define MEM_RSRC_PRINTK_SIZE 10 441 #endif 442 static const struct printf_spec io_spec = { 443 .base = 16, 444 .field_width = IO_RSRC_PRINTK_SIZE, 445 .precision = -1, 446 .flags = SPECIAL | SMALL | ZEROPAD, 447 }; 448 static const struct printf_spec mem_spec = { 449 .base = 16, 450 .field_width = MEM_RSRC_PRINTK_SIZE, 451 .precision = -1, 452 .flags = SPECIAL | SMALL | ZEROPAD, 453 }; 454 static const struct printf_spec bus_spec = { 455 .base = 16, 456 .field_width = 2, 457 .precision = -1, 458 .flags = SMALL | ZEROPAD, 459 }; 460 static const struct printf_spec dec_spec = { 461 .base = 10, 462 .precision = -1, 463 .flags = 0, 464 }; 465 static const struct printf_spec str_spec = { 466 .field_width = -1, 467 .precision = 10, 468 .flags = LEFT, 469 }; 470 static const struct printf_spec flag_spec = { 471 .base = 16, 472 .precision = -1, 473 .flags = SPECIAL | SMALL, 474 }; 475 476 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) 477 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ 478 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) 479 #define FLAG_BUF_SIZE (2 * sizeof(res->flags)) 480 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") 481 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]") 482 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 483 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; 484 485 char *p = sym, *pend = sym + sizeof(sym); 486 int decode = (fmt[0] == 'R') ? 1 : 0; 487 const struct printf_spec *specp; 488 489 *p++ = '['; 490 if (res->flags & IORESOURCE_IO) { 491 p = string(p, pend, "io ", str_spec); 492 specp = &io_spec; 493 } else if (res->flags & IORESOURCE_MEM) { 494 p = string(p, pend, "mem ", str_spec); 495 specp = &mem_spec; 496 } else if (res->flags & IORESOURCE_IRQ) { 497 p = string(p, pend, "irq ", str_spec); 498 specp = &dec_spec; 499 } else if (res->flags & IORESOURCE_DMA) { 500 p = string(p, pend, "dma ", str_spec); 501 specp = &dec_spec; 502 } else if (res->flags & IORESOURCE_BUS) { 503 p = string(p, pend, "bus ", str_spec); 504 specp = &bus_spec; 505 } else { 506 p = string(p, pend, "??? ", str_spec); 507 specp = &mem_spec; 508 decode = 0; 509 } 510 p = number(p, pend, res->start, *specp); 511 if (res->start != res->end) { 512 *p++ = '-'; 513 p = number(p, pend, res->end, *specp); 514 } 515 if (decode) { 516 if (res->flags & IORESOURCE_MEM_64) 517 p = string(p, pend, " 64bit", str_spec); 518 if (res->flags & IORESOURCE_PREFETCH) 519 p = string(p, pend, " pref", str_spec); 520 if (res->flags & IORESOURCE_WINDOW) 521 p = string(p, pend, " window", str_spec); 522 if (res->flags & IORESOURCE_DISABLED) 523 p = string(p, pend, " disabled", str_spec); 524 } else { 525 p = string(p, pend, " flags ", str_spec); 526 p = number(p, pend, res->flags, flag_spec); 527 } 528 *p++ = ']'; 529 *p = '\0'; 530 531 return string(buf, end, sym, spec); 532 } 533 534 static noinline_for_stack 535 char *mac_address_string(char *buf, char *end, u8 *addr, 536 struct printf_spec spec, const char *fmt) 537 { 538 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; 539 char *p = mac_addr; 540 int i; 541 char separator; 542 543 if (fmt[1] == 'F') { /* FDDI canonical format */ 544 separator = '-'; 545 } else { 546 separator = ':'; 547 } 548 549 for (i = 0; i < 6; i++) { 550 p = hex_byte_pack(p, addr[i]); 551 if (fmt[0] == 'M' && i != 5) 552 *p++ = separator; 553 } 554 *p = '\0'; 555 556 return string(buf, end, mac_addr, spec); 557 } 558 559 static noinline_for_stack 560 char *ip4_string(char *p, const u8 *addr, const char *fmt) 561 { 562 int i; 563 bool leading_zeros = (fmt[0] == 'i'); 564 int index; 565 int step; 566 567 switch (fmt[2]) { 568 case 'h': 569 #ifdef __BIG_ENDIAN 570 index = 0; 571 step = 1; 572 #else 573 index = 3; 574 step = -1; 575 #endif 576 break; 577 case 'l': 578 index = 3; 579 step = -1; 580 break; 581 case 'n': 582 case 'b': 583 default: 584 index = 0; 585 step = 1; 586 break; 587 } 588 for (i = 0; i < 4; i++) { 589 char temp[3]; /* hold each IP quad in reverse order */ 590 int digits = put_dec_trunc(temp, addr[index]) - temp; 591 if (leading_zeros) { 592 if (digits < 3) 593 *p++ = '0'; 594 if (digits < 2) 595 *p++ = '0'; 596 } 597 /* reverse the digits in the quad */ 598 while (digits--) 599 *p++ = temp[digits]; 600 if (i < 3) 601 *p++ = '.'; 602 index += step; 603 } 604 *p = '\0'; 605 606 return p; 607 } 608 609 static noinline_for_stack 610 char *ip6_compressed_string(char *p, const char *addr) 611 { 612 int i, j, range; 613 unsigned char zerolength[8]; 614 int longest = 1; 615 int colonpos = -1; 616 u16 word; 617 u8 hi, lo; 618 bool needcolon = false; 619 bool useIPv4; 620 struct in6_addr in6; 621 622 memcpy(&in6, addr, sizeof(struct in6_addr)); 623 624 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6); 625 626 memset(zerolength, 0, sizeof(zerolength)); 627 628 if (useIPv4) 629 range = 6; 630 else 631 range = 8; 632 633 /* find position of longest 0 run */ 634 for (i = 0; i < range; i++) { 635 for (j = i; j < range; j++) { 636 if (in6.s6_addr16[j] != 0) 637 break; 638 zerolength[i]++; 639 } 640 } 641 for (i = 0; i < range; i++) { 642 if (zerolength[i] > longest) { 643 longest = zerolength[i]; 644 colonpos = i; 645 } 646 } 647 if (longest == 1) /* don't compress a single 0 */ 648 colonpos = -1; 649 650 /* emit address */ 651 for (i = 0; i < range; i++) { 652 if (i == colonpos) { 653 if (needcolon || i == 0) 654 *p++ = ':'; 655 *p++ = ':'; 656 needcolon = false; 657 i += longest - 1; 658 continue; 659 } 660 if (needcolon) { 661 *p++ = ':'; 662 needcolon = false; 663 } 664 /* hex u16 without leading 0s */ 665 word = ntohs(in6.s6_addr16[i]); 666 hi = word >> 8; 667 lo = word & 0xff; 668 if (hi) { 669 if (hi > 0x0f) 670 p = hex_byte_pack(p, hi); 671 else 672 *p++ = hex_asc_lo(hi); 673 p = hex_byte_pack(p, lo); 674 } 675 else if (lo > 0x0f) 676 p = hex_byte_pack(p, lo); 677 else 678 *p++ = hex_asc_lo(lo); 679 needcolon = true; 680 } 681 682 if (useIPv4) { 683 if (needcolon) 684 *p++ = ':'; 685 p = ip4_string(p, &in6.s6_addr[12], "I4"); 686 } 687 *p = '\0'; 688 689 return p; 690 } 691 692 static noinline_for_stack 693 char *ip6_string(char *p, const char *addr, const char *fmt) 694 { 695 int i; 696 697 for (i = 0; i < 8; i++) { 698 p = hex_byte_pack(p, *addr++); 699 p = hex_byte_pack(p, *addr++); 700 if (fmt[0] == 'I' && i != 7) 701 *p++ = ':'; 702 } 703 *p = '\0'; 704 705 return p; 706 } 707 708 static noinline_for_stack 709 char *ip6_addr_string(char *buf, char *end, const u8 *addr, 710 struct printf_spec spec, const char *fmt) 711 { 712 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 713 714 if (fmt[0] == 'I' && fmt[2] == 'c') 715 ip6_compressed_string(ip6_addr, addr); 716 else 717 ip6_string(ip6_addr, addr, fmt); 718 719 return string(buf, end, ip6_addr, spec); 720 } 721 722 static noinline_for_stack 723 char *ip4_addr_string(char *buf, char *end, const u8 *addr, 724 struct printf_spec spec, const char *fmt) 725 { 726 char ip4_addr[sizeof("255.255.255.255")]; 727 728 ip4_string(ip4_addr, addr, fmt); 729 730 return string(buf, end, ip4_addr, spec); 731 } 732 733 static noinline_for_stack 734 char *uuid_string(char *buf, char *end, const u8 *addr, 735 struct printf_spec spec, const char *fmt) 736 { 737 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")]; 738 char *p = uuid; 739 int i; 740 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15}; 741 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15}; 742 const u8 *index = be; 743 bool uc = false; 744 745 switch (*(++fmt)) { 746 case 'L': 747 uc = true; /* fall-through */ 748 case 'l': 749 index = le; 750 break; 751 case 'B': 752 uc = true; 753 break; 754 } 755 756 for (i = 0; i < 16; i++) { 757 p = hex_byte_pack(p, addr[index[i]]); 758 switch (i) { 759 case 3: 760 case 5: 761 case 7: 762 case 9: 763 *p++ = '-'; 764 break; 765 } 766 } 767 768 *p = 0; 769 770 if (uc) { 771 p = uuid; 772 do { 773 *p = toupper(*p); 774 } while (*(++p)); 775 } 776 777 return string(buf, end, uuid, spec); 778 } 779 780 static 781 char *netdev_feature_string(char *buf, char *end, const u8 *addr, 782 struct printf_spec spec) 783 { 784 spec.flags |= SPECIAL | SMALL | ZEROPAD; 785 if (spec.field_width == -1) 786 spec.field_width = 2 + 2 * sizeof(netdev_features_t); 787 spec.base = 16; 788 789 return number(buf, end, *(const netdev_features_t *)addr, spec); 790 } 791 792 int kptr_restrict __read_mostly; 793 794 /* 795 * Show a '%p' thing. A kernel extension is that the '%p' is followed 796 * by an extra set of alphanumeric characters that are extended format 797 * specifiers. 798 * 799 * Right now we handle: 800 * 801 * - 'F' For symbolic function descriptor pointers with offset 802 * - 'f' For simple symbolic function names without offset 803 * - 'S' For symbolic direct pointers with offset 804 * - 's' For symbolic direct pointers without offset 805 * - 'B' For backtraced symbolic direct pointers with offset 806 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 807 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 808 * - 'M' For a 6-byte MAC address, it prints the address in the 809 * usual colon-separated hex notation 810 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 811 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 812 * with a dash-separated hex notation 813 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 814 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 815 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 816 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 817 * IPv6 omits the colons (01020304...0f) 818 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 819 * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order 820 * - 'I6c' for IPv6 addresses printed as specified by 821 * http://tools.ietf.org/html/rfc5952 822 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 823 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 824 * Options for %pU are: 825 * b big endian lower case hex (default) 826 * B big endian UPPER case hex 827 * l little endian lower case hex 828 * L little endian UPPER case hex 829 * big endian output byte order is: 830 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 831 * little endian output byte order is: 832 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 833 * - 'V' For a struct va_format which contains a format string * and va_list *, 834 * call vsnprintf(->format, *->va_list). 835 * Implements a "recursive vsnprintf". 836 * Do not use this feature without some mechanism to verify the 837 * correctness of the format string and va_list arguments. 838 * - 'K' For a kernel pointer that should be hidden from unprivileged users 839 * - 'NF' For a netdev_features_t 840 * 841 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64 842 * function pointers are really function descriptors, which contain a 843 * pointer to the real address. 844 */ 845 static noinline_for_stack 846 char *pointer(const char *fmt, char *buf, char *end, void *ptr, 847 struct printf_spec spec) 848 { 849 if (!ptr && *fmt != 'K') { 850 /* 851 * Print (null) with the same width as a pointer so it makes 852 * tabular output look nice. 853 */ 854 if (spec.field_width == -1) 855 spec.field_width = 2 * sizeof(void *); 856 return string(buf, end, "(null)", spec); 857 } 858 859 switch (*fmt) { 860 case 'F': 861 case 'f': 862 ptr = dereference_function_descriptor(ptr); 863 /* Fallthrough */ 864 case 'S': 865 case 's': 866 case 'B': 867 return symbol_string(buf, end, ptr, spec, *fmt); 868 case 'R': 869 case 'r': 870 return resource_string(buf, end, ptr, spec, fmt); 871 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 872 case 'm': /* Contiguous: 000102030405 */ 873 /* [mM]F (FDDI, bit reversed) */ 874 return mac_address_string(buf, end, ptr, spec, fmt); 875 case 'I': /* Formatted IP supported 876 * 4: 1.2.3.4 877 * 6: 0001:0203:...:0708 878 * 6c: 1::708 or 1::1.2.3.4 879 */ 880 case 'i': /* Contiguous: 881 * 4: 001.002.003.004 882 * 6: 000102...0f 883 */ 884 switch (fmt[1]) { 885 case '6': 886 return ip6_addr_string(buf, end, ptr, spec, fmt); 887 case '4': 888 return ip4_addr_string(buf, end, ptr, spec, fmt); 889 } 890 break; 891 case 'U': 892 return uuid_string(buf, end, ptr, spec, fmt); 893 case 'V': 894 { 895 va_list va; 896 897 va_copy(va, *((struct va_format *)ptr)->va); 898 buf += vsnprintf(buf, end > buf ? end - buf : 0, 899 ((struct va_format *)ptr)->fmt, va); 900 va_end(va); 901 return buf; 902 } 903 case 'K': 904 /* 905 * %pK cannot be used in IRQ context because its test 906 * for CAP_SYSLOG would be meaningless. 907 */ 908 if (in_irq() || in_serving_softirq() || in_nmi()) { 909 if (spec.field_width == -1) 910 spec.field_width = 2 * sizeof(void *); 911 return string(buf, end, "pK-error", spec); 912 } 913 if (!((kptr_restrict == 0) || 914 (kptr_restrict == 1 && 915 has_capability_noaudit(current, CAP_SYSLOG)))) 916 ptr = NULL; 917 break; 918 case 'N': 919 switch (fmt[1]) { 920 case 'F': 921 return netdev_feature_string(buf, end, ptr, spec); 922 } 923 break; 924 } 925 spec.flags |= SMALL; 926 if (spec.field_width == -1) { 927 spec.field_width = 2 * sizeof(void *); 928 spec.flags |= ZEROPAD; 929 } 930 spec.base = 16; 931 932 return number(buf, end, (unsigned long) ptr, spec); 933 } 934 935 /* 936 * Helper function to decode printf style format. 937 * Each call decode a token from the format and return the 938 * number of characters read (or likely the delta where it wants 939 * to go on the next call). 940 * The decoded token is returned through the parameters 941 * 942 * 'h', 'l', or 'L' for integer fields 943 * 'z' support added 23/7/1999 S.H. 944 * 'z' changed to 'Z' --davidm 1/25/99 945 * 't' added for ptrdiff_t 946 * 947 * @fmt: the format string 948 * @type of the token returned 949 * @flags: various flags such as +, -, # tokens.. 950 * @field_width: overwritten width 951 * @base: base of the number (octal, hex, ...) 952 * @precision: precision of a number 953 * @qualifier: qualifier of a number (long, size_t, ...) 954 */ 955 static noinline_for_stack 956 int format_decode(const char *fmt, struct printf_spec *spec) 957 { 958 const char *start = fmt; 959 960 /* we finished early by reading the field width */ 961 if (spec->type == FORMAT_TYPE_WIDTH) { 962 if (spec->field_width < 0) { 963 spec->field_width = -spec->field_width; 964 spec->flags |= LEFT; 965 } 966 spec->type = FORMAT_TYPE_NONE; 967 goto precision; 968 } 969 970 /* we finished early by reading the precision */ 971 if (spec->type == FORMAT_TYPE_PRECISION) { 972 if (spec->precision < 0) 973 spec->precision = 0; 974 975 spec->type = FORMAT_TYPE_NONE; 976 goto qualifier; 977 } 978 979 /* By default */ 980 spec->type = FORMAT_TYPE_NONE; 981 982 for (; *fmt ; ++fmt) { 983 if (*fmt == '%') 984 break; 985 } 986 987 /* Return the current non-format string */ 988 if (fmt != start || !*fmt) 989 return fmt - start; 990 991 /* Process flags */ 992 spec->flags = 0; 993 994 while (1) { /* this also skips first '%' */ 995 bool found = true; 996 997 ++fmt; 998 999 switch (*fmt) { 1000 case '-': spec->flags |= LEFT; break; 1001 case '+': spec->flags |= PLUS; break; 1002 case ' ': spec->flags |= SPACE; break; 1003 case '#': spec->flags |= SPECIAL; break; 1004 case '0': spec->flags |= ZEROPAD; break; 1005 default: found = false; 1006 } 1007 1008 if (!found) 1009 break; 1010 } 1011 1012 /* get field width */ 1013 spec->field_width = -1; 1014 1015 if (isdigit(*fmt)) 1016 spec->field_width = skip_atoi(&fmt); 1017 else if (*fmt == '*') { 1018 /* it's the next argument */ 1019 spec->type = FORMAT_TYPE_WIDTH; 1020 return ++fmt - start; 1021 } 1022 1023 precision: 1024 /* get the precision */ 1025 spec->precision = -1; 1026 if (*fmt == '.') { 1027 ++fmt; 1028 if (isdigit(*fmt)) { 1029 spec->precision = skip_atoi(&fmt); 1030 if (spec->precision < 0) 1031 spec->precision = 0; 1032 } else if (*fmt == '*') { 1033 /* it's the next argument */ 1034 spec->type = FORMAT_TYPE_PRECISION; 1035 return ++fmt - start; 1036 } 1037 } 1038 1039 qualifier: 1040 /* get the conversion qualifier */ 1041 spec->qualifier = -1; 1042 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 1043 _tolower(*fmt) == 'z' || *fmt == 't') { 1044 spec->qualifier = *fmt++; 1045 if (unlikely(spec->qualifier == *fmt)) { 1046 if (spec->qualifier == 'l') { 1047 spec->qualifier = 'L'; 1048 ++fmt; 1049 } else if (spec->qualifier == 'h') { 1050 spec->qualifier = 'H'; 1051 ++fmt; 1052 } 1053 } 1054 } 1055 1056 /* default base */ 1057 spec->base = 10; 1058 switch (*fmt) { 1059 case 'c': 1060 spec->type = FORMAT_TYPE_CHAR; 1061 return ++fmt - start; 1062 1063 case 's': 1064 spec->type = FORMAT_TYPE_STR; 1065 return ++fmt - start; 1066 1067 case 'p': 1068 spec->type = FORMAT_TYPE_PTR; 1069 return fmt - start; 1070 /* skip alnum */ 1071 1072 case 'n': 1073 spec->type = FORMAT_TYPE_NRCHARS; 1074 return ++fmt - start; 1075 1076 case '%': 1077 spec->type = FORMAT_TYPE_PERCENT_CHAR; 1078 return ++fmt - start; 1079 1080 /* integer number formats - set up the flags and "break" */ 1081 case 'o': 1082 spec->base = 8; 1083 break; 1084 1085 case 'x': 1086 spec->flags |= SMALL; 1087 1088 case 'X': 1089 spec->base = 16; 1090 break; 1091 1092 case 'd': 1093 case 'i': 1094 spec->flags |= SIGN; 1095 case 'u': 1096 break; 1097 1098 default: 1099 spec->type = FORMAT_TYPE_INVALID; 1100 return fmt - start; 1101 } 1102 1103 if (spec->qualifier == 'L') 1104 spec->type = FORMAT_TYPE_LONG_LONG; 1105 else if (spec->qualifier == 'l') { 1106 if (spec->flags & SIGN) 1107 spec->type = FORMAT_TYPE_LONG; 1108 else 1109 spec->type = FORMAT_TYPE_ULONG; 1110 } else if (_tolower(spec->qualifier) == 'z') { 1111 spec->type = FORMAT_TYPE_SIZE_T; 1112 } else if (spec->qualifier == 't') { 1113 spec->type = FORMAT_TYPE_PTRDIFF; 1114 } else if (spec->qualifier == 'H') { 1115 if (spec->flags & SIGN) 1116 spec->type = FORMAT_TYPE_BYTE; 1117 else 1118 spec->type = FORMAT_TYPE_UBYTE; 1119 } else if (spec->qualifier == 'h') { 1120 if (spec->flags & SIGN) 1121 spec->type = FORMAT_TYPE_SHORT; 1122 else 1123 spec->type = FORMAT_TYPE_USHORT; 1124 } else { 1125 if (spec->flags & SIGN) 1126 spec->type = FORMAT_TYPE_INT; 1127 else 1128 spec->type = FORMAT_TYPE_UINT; 1129 } 1130 1131 return ++fmt - start; 1132 } 1133 1134 /** 1135 * vsnprintf - Format a string and place it in a buffer 1136 * @buf: The buffer to place the result into 1137 * @size: The size of the buffer, including the trailing null space 1138 * @fmt: The format string to use 1139 * @args: Arguments for the format string 1140 * 1141 * This function follows C99 vsnprintf, but has some extensions: 1142 * %pS output the name of a text symbol with offset 1143 * %ps output the name of a text symbol without offset 1144 * %pF output the name of a function pointer with its offset 1145 * %pf output the name of a function pointer without its offset 1146 * %pB output the name of a backtrace symbol with its offset 1147 * %pR output the address range in a struct resource with decoded flags 1148 * %pr output the address range in a struct resource with raw flags 1149 * %pM output a 6-byte MAC address with colons 1150 * %pm output a 6-byte MAC address without colons 1151 * %pI4 print an IPv4 address without leading zeros 1152 * %pi4 print an IPv4 address with leading zeros 1153 * %pI6 print an IPv6 address with colons 1154 * %pi6 print an IPv6 address without colons 1155 * %pI6c print an IPv6 address as specified by RFC 5952 1156 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper 1157 * case. 1158 * %n is ignored 1159 * 1160 * The return value is the number of characters which would 1161 * be generated for the given input, excluding the trailing 1162 * '\0', as per ISO C99. If you want to have the exact 1163 * number of characters written into @buf as return value 1164 * (not including the trailing '\0'), use vscnprintf(). If the 1165 * return is greater than or equal to @size, the resulting 1166 * string is truncated. 1167 * 1168 * If you're not already dealing with a va_list consider using snprintf(). 1169 */ 1170 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) 1171 { 1172 unsigned long long num; 1173 char *str, *end; 1174 struct printf_spec spec = {0}; 1175 1176 /* Reject out-of-range values early. Large positive sizes are 1177 used for unknown buffer sizes. */ 1178 if (WARN_ON_ONCE((int) size < 0)) 1179 return 0; 1180 1181 str = buf; 1182 end = buf + size; 1183 1184 /* Make sure end is always >= buf */ 1185 if (end < buf) { 1186 end = ((void *)-1); 1187 size = end - buf; 1188 } 1189 1190 while (*fmt) { 1191 const char *old_fmt = fmt; 1192 int read = format_decode(fmt, &spec); 1193 1194 fmt += read; 1195 1196 switch (spec.type) { 1197 case FORMAT_TYPE_NONE: { 1198 int copy = read; 1199 if (str < end) { 1200 if (copy > end - str) 1201 copy = end - str; 1202 memcpy(str, old_fmt, copy); 1203 } 1204 str += read; 1205 break; 1206 } 1207 1208 case FORMAT_TYPE_WIDTH: 1209 spec.field_width = va_arg(args, int); 1210 break; 1211 1212 case FORMAT_TYPE_PRECISION: 1213 spec.precision = va_arg(args, int); 1214 break; 1215 1216 case FORMAT_TYPE_CHAR: { 1217 char c; 1218 1219 if (!(spec.flags & LEFT)) { 1220 while (--spec.field_width > 0) { 1221 if (str < end) 1222 *str = ' '; 1223 ++str; 1224 1225 } 1226 } 1227 c = (unsigned char) va_arg(args, int); 1228 if (str < end) 1229 *str = c; 1230 ++str; 1231 while (--spec.field_width > 0) { 1232 if (str < end) 1233 *str = ' '; 1234 ++str; 1235 } 1236 break; 1237 } 1238 1239 case FORMAT_TYPE_STR: 1240 str = string(str, end, va_arg(args, char *), spec); 1241 break; 1242 1243 case FORMAT_TYPE_PTR: 1244 str = pointer(fmt+1, str, end, va_arg(args, void *), 1245 spec); 1246 while (isalnum(*fmt)) 1247 fmt++; 1248 break; 1249 1250 case FORMAT_TYPE_PERCENT_CHAR: 1251 if (str < end) 1252 *str = '%'; 1253 ++str; 1254 break; 1255 1256 case FORMAT_TYPE_INVALID: 1257 if (str < end) 1258 *str = '%'; 1259 ++str; 1260 break; 1261 1262 case FORMAT_TYPE_NRCHARS: { 1263 u8 qualifier = spec.qualifier; 1264 1265 if (qualifier == 'l') { 1266 long *ip = va_arg(args, long *); 1267 *ip = (str - buf); 1268 } else if (_tolower(qualifier) == 'z') { 1269 size_t *ip = va_arg(args, size_t *); 1270 *ip = (str - buf); 1271 } else { 1272 int *ip = va_arg(args, int *); 1273 *ip = (str - buf); 1274 } 1275 break; 1276 } 1277 1278 default: 1279 switch (spec.type) { 1280 case FORMAT_TYPE_LONG_LONG: 1281 num = va_arg(args, long long); 1282 break; 1283 case FORMAT_TYPE_ULONG: 1284 num = va_arg(args, unsigned long); 1285 break; 1286 case FORMAT_TYPE_LONG: 1287 num = va_arg(args, long); 1288 break; 1289 case FORMAT_TYPE_SIZE_T: 1290 num = va_arg(args, size_t); 1291 break; 1292 case FORMAT_TYPE_PTRDIFF: 1293 num = va_arg(args, ptrdiff_t); 1294 break; 1295 case FORMAT_TYPE_UBYTE: 1296 num = (unsigned char) va_arg(args, int); 1297 break; 1298 case FORMAT_TYPE_BYTE: 1299 num = (signed char) va_arg(args, int); 1300 break; 1301 case FORMAT_TYPE_USHORT: 1302 num = (unsigned short) va_arg(args, int); 1303 break; 1304 case FORMAT_TYPE_SHORT: 1305 num = (short) va_arg(args, int); 1306 break; 1307 case FORMAT_TYPE_INT: 1308 num = (int) va_arg(args, int); 1309 break; 1310 default: 1311 num = va_arg(args, unsigned int); 1312 } 1313 1314 str = number(str, end, num, spec); 1315 } 1316 } 1317 1318 if (size > 0) { 1319 if (str < end) 1320 *str = '\0'; 1321 else 1322 end[-1] = '\0'; 1323 } 1324 1325 /* the trailing null byte doesn't count towards the total */ 1326 return str-buf; 1327 1328 } 1329 EXPORT_SYMBOL(vsnprintf); 1330 1331 /** 1332 * vscnprintf - Format a string and place it in a buffer 1333 * @buf: The buffer to place the result into 1334 * @size: The size of the buffer, including the trailing null space 1335 * @fmt: The format string to use 1336 * @args: Arguments for the format string 1337 * 1338 * The return value is the number of characters which have been written into 1339 * the @buf not including the trailing '\0'. If @size is == 0 the function 1340 * returns 0. 1341 * 1342 * If you're not already dealing with a va_list consider using scnprintf(). 1343 * 1344 * See the vsnprintf() documentation for format string extensions over C99. 1345 */ 1346 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 1347 { 1348 int i; 1349 1350 i = vsnprintf(buf, size, fmt, args); 1351 1352 if (likely(i < size)) 1353 return i; 1354 if (size != 0) 1355 return size - 1; 1356 return 0; 1357 } 1358 EXPORT_SYMBOL(vscnprintf); 1359 1360 /** 1361 * snprintf - Format a string and place it in a buffer 1362 * @buf: The buffer to place the result into 1363 * @size: The size of the buffer, including the trailing null space 1364 * @fmt: The format string to use 1365 * @...: Arguments for the format string 1366 * 1367 * The return value is the number of characters which would be 1368 * generated for the given input, excluding the trailing null, 1369 * as per ISO C99. If the return is greater than or equal to 1370 * @size, the resulting string is truncated. 1371 * 1372 * See the vsnprintf() documentation for format string extensions over C99. 1373 */ 1374 int snprintf(char *buf, size_t size, const char *fmt, ...) 1375 { 1376 va_list args; 1377 int i; 1378 1379 va_start(args, fmt); 1380 i = vsnprintf(buf, size, fmt, args); 1381 va_end(args); 1382 1383 return i; 1384 } 1385 EXPORT_SYMBOL(snprintf); 1386 1387 /** 1388 * scnprintf - Format a string and place it in a buffer 1389 * @buf: The buffer to place the result into 1390 * @size: The size of the buffer, including the trailing null space 1391 * @fmt: The format string to use 1392 * @...: Arguments for the format string 1393 * 1394 * The return value is the number of characters written into @buf not including 1395 * the trailing '\0'. If @size is == 0 the function returns 0. 1396 */ 1397 1398 int scnprintf(char *buf, size_t size, const char *fmt, ...) 1399 { 1400 va_list args; 1401 int i; 1402 1403 va_start(args, fmt); 1404 i = vscnprintf(buf, size, fmt, args); 1405 va_end(args); 1406 1407 return i; 1408 } 1409 EXPORT_SYMBOL(scnprintf); 1410 1411 /** 1412 * vsprintf - Format a string and place it in a buffer 1413 * @buf: The buffer to place the result into 1414 * @fmt: The format string to use 1415 * @args: Arguments for the format string 1416 * 1417 * The function returns the number of characters written 1418 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid 1419 * buffer overflows. 1420 * 1421 * If you're not already dealing with a va_list consider using sprintf(). 1422 * 1423 * See the vsnprintf() documentation for format string extensions over C99. 1424 */ 1425 int vsprintf(char *buf, const char *fmt, va_list args) 1426 { 1427 return vsnprintf(buf, INT_MAX, fmt, args); 1428 } 1429 EXPORT_SYMBOL(vsprintf); 1430 1431 /** 1432 * sprintf - Format a string and place it in a buffer 1433 * @buf: The buffer to place the result into 1434 * @fmt: The format string to use 1435 * @...: Arguments for the format string 1436 * 1437 * The function returns the number of characters written 1438 * into @buf. Use snprintf() or scnprintf() in order to avoid 1439 * buffer overflows. 1440 * 1441 * See the vsnprintf() documentation for format string extensions over C99. 1442 */ 1443 int sprintf(char *buf, const char *fmt, ...) 1444 { 1445 va_list args; 1446 int i; 1447 1448 va_start(args, fmt); 1449 i = vsnprintf(buf, INT_MAX, fmt, args); 1450 va_end(args); 1451 1452 return i; 1453 } 1454 EXPORT_SYMBOL(sprintf); 1455 1456 #ifdef CONFIG_BINARY_PRINTF 1457 /* 1458 * bprintf service: 1459 * vbin_printf() - VA arguments to binary data 1460 * bstr_printf() - Binary data to text string 1461 */ 1462 1463 /** 1464 * vbin_printf - Parse a format string and place args' binary value in a buffer 1465 * @bin_buf: The buffer to place args' binary value 1466 * @size: The size of the buffer(by words(32bits), not characters) 1467 * @fmt: The format string to use 1468 * @args: Arguments for the format string 1469 * 1470 * The format follows C99 vsnprintf, except %n is ignored, and its argument 1471 * is skiped. 1472 * 1473 * The return value is the number of words(32bits) which would be generated for 1474 * the given input. 1475 * 1476 * NOTE: 1477 * If the return value is greater than @size, the resulting bin_buf is NOT 1478 * valid for bstr_printf(). 1479 */ 1480 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args) 1481 { 1482 struct printf_spec spec = {0}; 1483 char *str, *end; 1484 1485 str = (char *)bin_buf; 1486 end = (char *)(bin_buf + size); 1487 1488 #define save_arg(type) \ 1489 do { \ 1490 if (sizeof(type) == 8) { \ 1491 unsigned long long value; \ 1492 str = PTR_ALIGN(str, sizeof(u32)); \ 1493 value = va_arg(args, unsigned long long); \ 1494 if (str + sizeof(type) <= end) { \ 1495 *(u32 *)str = *(u32 *)&value; \ 1496 *(u32 *)(str + 4) = *((u32 *)&value + 1); \ 1497 } \ 1498 } else { \ 1499 unsigned long value; \ 1500 str = PTR_ALIGN(str, sizeof(type)); \ 1501 value = va_arg(args, int); \ 1502 if (str + sizeof(type) <= end) \ 1503 *(typeof(type) *)str = (type)value; \ 1504 } \ 1505 str += sizeof(type); \ 1506 } while (0) 1507 1508 while (*fmt) { 1509 int read = format_decode(fmt, &spec); 1510 1511 fmt += read; 1512 1513 switch (spec.type) { 1514 case FORMAT_TYPE_NONE: 1515 case FORMAT_TYPE_INVALID: 1516 case FORMAT_TYPE_PERCENT_CHAR: 1517 break; 1518 1519 case FORMAT_TYPE_WIDTH: 1520 case FORMAT_TYPE_PRECISION: 1521 save_arg(int); 1522 break; 1523 1524 case FORMAT_TYPE_CHAR: 1525 save_arg(char); 1526 break; 1527 1528 case FORMAT_TYPE_STR: { 1529 const char *save_str = va_arg(args, char *); 1530 size_t len; 1531 1532 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE 1533 || (unsigned long)save_str < PAGE_SIZE) 1534 save_str = "(null)"; 1535 len = strlen(save_str) + 1; 1536 if (str + len < end) 1537 memcpy(str, save_str, len); 1538 str += len; 1539 break; 1540 } 1541 1542 case FORMAT_TYPE_PTR: 1543 save_arg(void *); 1544 /* skip all alphanumeric pointer suffixes */ 1545 while (isalnum(*fmt)) 1546 fmt++; 1547 break; 1548 1549 case FORMAT_TYPE_NRCHARS: { 1550 /* skip %n 's argument */ 1551 u8 qualifier = spec.qualifier; 1552 void *skip_arg; 1553 if (qualifier == 'l') 1554 skip_arg = va_arg(args, long *); 1555 else if (_tolower(qualifier) == 'z') 1556 skip_arg = va_arg(args, size_t *); 1557 else 1558 skip_arg = va_arg(args, int *); 1559 break; 1560 } 1561 1562 default: 1563 switch (spec.type) { 1564 1565 case FORMAT_TYPE_LONG_LONG: 1566 save_arg(long long); 1567 break; 1568 case FORMAT_TYPE_ULONG: 1569 case FORMAT_TYPE_LONG: 1570 save_arg(unsigned long); 1571 break; 1572 case FORMAT_TYPE_SIZE_T: 1573 save_arg(size_t); 1574 break; 1575 case FORMAT_TYPE_PTRDIFF: 1576 save_arg(ptrdiff_t); 1577 break; 1578 case FORMAT_TYPE_UBYTE: 1579 case FORMAT_TYPE_BYTE: 1580 save_arg(char); 1581 break; 1582 case FORMAT_TYPE_USHORT: 1583 case FORMAT_TYPE_SHORT: 1584 save_arg(short); 1585 break; 1586 default: 1587 save_arg(int); 1588 } 1589 } 1590 } 1591 1592 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 1593 #undef save_arg 1594 } 1595 EXPORT_SYMBOL_GPL(vbin_printf); 1596 1597 /** 1598 * bstr_printf - Format a string from binary arguments and place it in a buffer 1599 * @buf: The buffer to place the result into 1600 * @size: The size of the buffer, including the trailing null space 1601 * @fmt: The format string to use 1602 * @bin_buf: Binary arguments for the format string 1603 * 1604 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 1605 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 1606 * a binary buffer that generated by vbin_printf. 1607 * 1608 * The format follows C99 vsnprintf, but has some extensions: 1609 * see vsnprintf comment for details. 1610 * 1611 * The return value is the number of characters which would 1612 * be generated for the given input, excluding the trailing 1613 * '\0', as per ISO C99. If you want to have the exact 1614 * number of characters written into @buf as return value 1615 * (not including the trailing '\0'), use vscnprintf(). If the 1616 * return is greater than or equal to @size, the resulting 1617 * string is truncated. 1618 */ 1619 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) 1620 { 1621 struct printf_spec spec = {0}; 1622 char *str, *end; 1623 const char *args = (const char *)bin_buf; 1624 1625 if (WARN_ON_ONCE((int) size < 0)) 1626 return 0; 1627 1628 str = buf; 1629 end = buf + size; 1630 1631 #define get_arg(type) \ 1632 ({ \ 1633 typeof(type) value; \ 1634 if (sizeof(type) == 8) { \ 1635 args = PTR_ALIGN(args, sizeof(u32)); \ 1636 *(u32 *)&value = *(u32 *)args; \ 1637 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 1638 } else { \ 1639 args = PTR_ALIGN(args, sizeof(type)); \ 1640 value = *(typeof(type) *)args; \ 1641 } \ 1642 args += sizeof(type); \ 1643 value; \ 1644 }) 1645 1646 /* Make sure end is always >= buf */ 1647 if (end < buf) { 1648 end = ((void *)-1); 1649 size = end - buf; 1650 } 1651 1652 while (*fmt) { 1653 const char *old_fmt = fmt; 1654 int read = format_decode(fmt, &spec); 1655 1656 fmt += read; 1657 1658 switch (spec.type) { 1659 case FORMAT_TYPE_NONE: { 1660 int copy = read; 1661 if (str < end) { 1662 if (copy > end - str) 1663 copy = end - str; 1664 memcpy(str, old_fmt, copy); 1665 } 1666 str += read; 1667 break; 1668 } 1669 1670 case FORMAT_TYPE_WIDTH: 1671 spec.field_width = get_arg(int); 1672 break; 1673 1674 case FORMAT_TYPE_PRECISION: 1675 spec.precision = get_arg(int); 1676 break; 1677 1678 case FORMAT_TYPE_CHAR: { 1679 char c; 1680 1681 if (!(spec.flags & LEFT)) { 1682 while (--spec.field_width > 0) { 1683 if (str < end) 1684 *str = ' '; 1685 ++str; 1686 } 1687 } 1688 c = (unsigned char) get_arg(char); 1689 if (str < end) 1690 *str = c; 1691 ++str; 1692 while (--spec.field_width > 0) { 1693 if (str < end) 1694 *str = ' '; 1695 ++str; 1696 } 1697 break; 1698 } 1699 1700 case FORMAT_TYPE_STR: { 1701 const char *str_arg = args; 1702 args += strlen(str_arg) + 1; 1703 str = string(str, end, (char *)str_arg, spec); 1704 break; 1705 } 1706 1707 case FORMAT_TYPE_PTR: 1708 str = pointer(fmt+1, str, end, get_arg(void *), spec); 1709 while (isalnum(*fmt)) 1710 fmt++; 1711 break; 1712 1713 case FORMAT_TYPE_PERCENT_CHAR: 1714 case FORMAT_TYPE_INVALID: 1715 if (str < end) 1716 *str = '%'; 1717 ++str; 1718 break; 1719 1720 case FORMAT_TYPE_NRCHARS: 1721 /* skip */ 1722 break; 1723 1724 default: { 1725 unsigned long long num; 1726 1727 switch (spec.type) { 1728 1729 case FORMAT_TYPE_LONG_LONG: 1730 num = get_arg(long long); 1731 break; 1732 case FORMAT_TYPE_ULONG: 1733 case FORMAT_TYPE_LONG: 1734 num = get_arg(unsigned long); 1735 break; 1736 case FORMAT_TYPE_SIZE_T: 1737 num = get_arg(size_t); 1738 break; 1739 case FORMAT_TYPE_PTRDIFF: 1740 num = get_arg(ptrdiff_t); 1741 break; 1742 case FORMAT_TYPE_UBYTE: 1743 num = get_arg(unsigned char); 1744 break; 1745 case FORMAT_TYPE_BYTE: 1746 num = get_arg(signed char); 1747 break; 1748 case FORMAT_TYPE_USHORT: 1749 num = get_arg(unsigned short); 1750 break; 1751 case FORMAT_TYPE_SHORT: 1752 num = get_arg(short); 1753 break; 1754 case FORMAT_TYPE_UINT: 1755 num = get_arg(unsigned int); 1756 break; 1757 default: 1758 num = get_arg(int); 1759 } 1760 1761 str = number(str, end, num, spec); 1762 } /* default: */ 1763 } /* switch(spec.type) */ 1764 } /* while(*fmt) */ 1765 1766 if (size > 0) { 1767 if (str < end) 1768 *str = '\0'; 1769 else 1770 end[-1] = '\0'; 1771 } 1772 1773 #undef get_arg 1774 1775 /* the trailing null byte doesn't count towards the total */ 1776 return str - buf; 1777 } 1778 EXPORT_SYMBOL_GPL(bstr_printf); 1779 1780 /** 1781 * bprintf - Parse a format string and place args' binary value in a buffer 1782 * @bin_buf: The buffer to place args' binary value 1783 * @size: The size of the buffer(by words(32bits), not characters) 1784 * @fmt: The format string to use 1785 * @...: Arguments for the format string 1786 * 1787 * The function returns the number of words(u32) written 1788 * into @bin_buf. 1789 */ 1790 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) 1791 { 1792 va_list args; 1793 int ret; 1794 1795 va_start(args, fmt); 1796 ret = vbin_printf(bin_buf, size, fmt, args); 1797 va_end(args); 1798 1799 return ret; 1800 } 1801 EXPORT_SYMBOL_GPL(bprintf); 1802 1803 #endif /* CONFIG_BINARY_PRINTF */ 1804 1805 /** 1806 * vsscanf - Unformat a buffer into a list of arguments 1807 * @buf: input buffer 1808 * @fmt: format of buffer 1809 * @args: arguments 1810 */ 1811 int vsscanf(const char *buf, const char *fmt, va_list args) 1812 { 1813 const char *str = buf; 1814 char *next; 1815 char digit; 1816 int num = 0; 1817 u8 qualifier; 1818 u8 base; 1819 s16 field_width; 1820 bool is_sign; 1821 1822 while (*fmt && *str) { 1823 /* skip any white space in format */ 1824 /* white space in format matchs any amount of 1825 * white space, including none, in the input. 1826 */ 1827 if (isspace(*fmt)) { 1828 fmt = skip_spaces(++fmt); 1829 str = skip_spaces(str); 1830 } 1831 1832 /* anything that is not a conversion must match exactly */ 1833 if (*fmt != '%' && *fmt) { 1834 if (*fmt++ != *str++) 1835 break; 1836 continue; 1837 } 1838 1839 if (!*fmt) 1840 break; 1841 ++fmt; 1842 1843 /* skip this conversion. 1844 * advance both strings to next white space 1845 */ 1846 if (*fmt == '*') { 1847 while (!isspace(*fmt) && *fmt != '%' && *fmt) 1848 fmt++; 1849 while (!isspace(*str) && *str) 1850 str++; 1851 continue; 1852 } 1853 1854 /* get field width */ 1855 field_width = -1; 1856 if (isdigit(*fmt)) 1857 field_width = skip_atoi(&fmt); 1858 1859 /* get conversion qualifier */ 1860 qualifier = -1; 1861 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 1862 _tolower(*fmt) == 'z') { 1863 qualifier = *fmt++; 1864 if (unlikely(qualifier == *fmt)) { 1865 if (qualifier == 'h') { 1866 qualifier = 'H'; 1867 fmt++; 1868 } else if (qualifier == 'l') { 1869 qualifier = 'L'; 1870 fmt++; 1871 } 1872 } 1873 } 1874 1875 if (!*fmt || !*str) 1876 break; 1877 1878 base = 10; 1879 is_sign = 0; 1880 1881 switch (*fmt++) { 1882 case 'c': 1883 { 1884 char *s = (char *)va_arg(args, char*); 1885 if (field_width == -1) 1886 field_width = 1; 1887 do { 1888 *s++ = *str++; 1889 } while (--field_width > 0 && *str); 1890 num++; 1891 } 1892 continue; 1893 case 's': 1894 { 1895 char *s = (char *)va_arg(args, char *); 1896 if (field_width == -1) 1897 field_width = SHRT_MAX; 1898 /* first, skip leading white space in buffer */ 1899 str = skip_spaces(str); 1900 1901 /* now copy until next white space */ 1902 while (*str && !isspace(*str) && field_width--) 1903 *s++ = *str++; 1904 *s = '\0'; 1905 num++; 1906 } 1907 continue; 1908 case 'n': 1909 /* return number of characters read so far */ 1910 { 1911 int *i = (int *)va_arg(args, int*); 1912 *i = str - buf; 1913 } 1914 continue; 1915 case 'o': 1916 base = 8; 1917 break; 1918 case 'x': 1919 case 'X': 1920 base = 16; 1921 break; 1922 case 'i': 1923 base = 0; 1924 case 'd': 1925 is_sign = 1; 1926 case 'u': 1927 break; 1928 case '%': 1929 /* looking for '%' in str */ 1930 if (*str++ != '%') 1931 return num; 1932 continue; 1933 default: 1934 /* invalid format; stop here */ 1935 return num; 1936 } 1937 1938 /* have some sort of integer conversion. 1939 * first, skip white space in buffer. 1940 */ 1941 str = skip_spaces(str); 1942 1943 digit = *str; 1944 if (is_sign && digit == '-') 1945 digit = *(str + 1); 1946 1947 if (!digit 1948 || (base == 16 && !isxdigit(digit)) 1949 || (base == 10 && !isdigit(digit)) 1950 || (base == 8 && (!isdigit(digit) || digit > '7')) 1951 || (base == 0 && !isdigit(digit))) 1952 break; 1953 1954 switch (qualifier) { 1955 case 'H': /* that's 'hh' in format */ 1956 if (is_sign) { 1957 signed char *s = (signed char *)va_arg(args, signed char *); 1958 *s = (signed char)simple_strtol(str, &next, base); 1959 } else { 1960 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *); 1961 *s = (unsigned char)simple_strtoul(str, &next, base); 1962 } 1963 break; 1964 case 'h': 1965 if (is_sign) { 1966 short *s = (short *)va_arg(args, short *); 1967 *s = (short)simple_strtol(str, &next, base); 1968 } else { 1969 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *); 1970 *s = (unsigned short)simple_strtoul(str, &next, base); 1971 } 1972 break; 1973 case 'l': 1974 if (is_sign) { 1975 long *l = (long *)va_arg(args, long *); 1976 *l = simple_strtol(str, &next, base); 1977 } else { 1978 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *); 1979 *l = simple_strtoul(str, &next, base); 1980 } 1981 break; 1982 case 'L': 1983 if (is_sign) { 1984 long long *l = (long long *)va_arg(args, long long *); 1985 *l = simple_strtoll(str, &next, base); 1986 } else { 1987 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *); 1988 *l = simple_strtoull(str, &next, base); 1989 } 1990 break; 1991 case 'Z': 1992 case 'z': 1993 { 1994 size_t *s = (size_t *)va_arg(args, size_t *); 1995 *s = (size_t)simple_strtoul(str, &next, base); 1996 } 1997 break; 1998 default: 1999 if (is_sign) { 2000 int *i = (int *)va_arg(args, int *); 2001 *i = (int)simple_strtol(str, &next, base); 2002 } else { 2003 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*); 2004 *i = (unsigned int)simple_strtoul(str, &next, base); 2005 } 2006 break; 2007 } 2008 num++; 2009 2010 if (!next) 2011 break; 2012 str = next; 2013 } 2014 2015 /* 2016 * Now we've come all the way through so either the input string or the 2017 * format ended. In the former case, there can be a %n at the current 2018 * position in the format that needs to be filled. 2019 */ 2020 if (*fmt == '%' && *(fmt + 1) == 'n') { 2021 int *p = (int *)va_arg(args, int *); 2022 *p = str - buf; 2023 } 2024 2025 return num; 2026 } 2027 EXPORT_SYMBOL(vsscanf); 2028 2029 /** 2030 * sscanf - Unformat a buffer into a list of arguments 2031 * @buf: input buffer 2032 * @fmt: formatting of buffer 2033 * @...: resulting arguments 2034 */ 2035 int sscanf(const char *buf, const char *fmt, ...) 2036 { 2037 va_list args; 2038 int i; 2039 2040 va_start(args, fmt); 2041 i = vsscanf(buf, fmt, args); 2042 va_end(args); 2043 2044 return i; 2045 } 2046 EXPORT_SYMBOL(sscanf); 2047