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 } 121 122 /** 123 * strict_strtoul - convert a string to an unsigned long strictly 124 * @cp: The string to be converted 125 * @base: The number base to use 126 * @res: The converted result value 127 * 128 * strict_strtoul converts a string to an unsigned long only if the 129 * string is really an unsigned long string, any string containing 130 * any invalid char at the tail will be rejected and -EINVAL is returned, 131 * only a newline char at the tail is acceptible because people generally 132 * change a module parameter in the following way: 133 * 134 * echo 1024 > /sys/module/e1000/parameters/copybreak 135 * 136 * echo will append a newline to the tail. 137 * 138 * It returns 0 if conversion is successful and *res is set to the converted 139 * value, otherwise it returns -EINVAL and *res is set to 0. 140 * 141 * simple_strtoul just ignores the successive invalid characters and 142 * return the converted value of prefix part of the string. 143 */ 144 int strict_strtoul(const char *cp, unsigned int base, unsigned long *res) 145 { 146 char *tail; 147 unsigned long val; 148 size_t len; 149 150 *res = 0; 151 len = strlen(cp); 152 if (len == 0) 153 return -EINVAL; 154 155 val = simple_strtoul(cp, &tail, base); 156 if (tail == cp) 157 return -EINVAL; 158 159 if ((*tail == '\0') || 160 ((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) { 161 *res = val; 162 return 0; 163 } 164 165 return -EINVAL; 166 } 167 EXPORT_SYMBOL(strict_strtoul); 168 169 /** 170 * strict_strtol - convert a string to a long strictly 171 * @cp: The string to be converted 172 * @base: The number base to use 173 * @res: The converted result value 174 * 175 * strict_strtol is similiar to strict_strtoul, but it allows the first 176 * character of a string is '-'. 177 * 178 * It returns 0 if conversion is successful and *res is set to the converted 179 * value, otherwise it returns -EINVAL and *res is set to 0. 180 */ 181 int strict_strtol(const char *cp, unsigned int base, long *res) 182 { 183 int ret; 184 if (*cp == '-') { 185 ret = strict_strtoul(cp + 1, base, (unsigned long *)res); 186 if (!ret) 187 *res = -(*res); 188 } else { 189 ret = strict_strtoul(cp, base, (unsigned long *)res); 190 } 191 192 return ret; 193 } 194 EXPORT_SYMBOL(strict_strtol); 195 196 /** 197 * strict_strtoull - convert a string to an unsigned long long strictly 198 * @cp: The string to be converted 199 * @base: The number base to use 200 * @res: The converted result value 201 * 202 * strict_strtoull converts a string to an unsigned long long only if the 203 * string is really an unsigned long long string, any string containing 204 * any invalid char at the tail will be rejected and -EINVAL is returned, 205 * only a newline char at the tail is acceptible because people generally 206 * change a module parameter in the following way: 207 * 208 * echo 1024 > /sys/module/e1000/parameters/copybreak 209 * 210 * echo will append a newline to the tail of the string. 211 * 212 * It returns 0 if conversion is successful and *res is set to the converted 213 * value, otherwise it returns -EINVAL and *res is set to 0. 214 * 215 * simple_strtoull just ignores the successive invalid characters and 216 * return the converted value of prefix part of the string. 217 */ 218 int strict_strtoull(const char *cp, unsigned int base, unsigned long long *res) 219 { 220 char *tail; 221 unsigned long long val; 222 size_t len; 223 224 *res = 0; 225 len = strlen(cp); 226 if (len == 0) 227 return -EINVAL; 228 229 val = simple_strtoull(cp, &tail, base); 230 if (tail == cp) 231 return -EINVAL; 232 if ((*tail == '\0') || 233 ((len == (size_t)(tail - cp) + 1) && (*tail == '\n'))) { 234 *res = val; 235 return 0; 236 } 237 238 return -EINVAL; 239 } 240 EXPORT_SYMBOL(strict_strtoull); 241 242 /** 243 * strict_strtoll - convert a string to a long long strictly 244 * @cp: The string to be converted 245 * @base: The number base to use 246 * @res: The converted result value 247 * 248 * strict_strtoll is similiar to strict_strtoull, but it allows the first 249 * character of a string is '-'. 250 * 251 * It returns 0 if conversion is successful and *res is set to the converted 252 * value, otherwise it returns -EINVAL and *res is set to 0. 253 */ 254 int strict_strtoll(const char *cp, unsigned int base, long long *res) 255 { 256 int ret; 257 if (*cp == '-') { 258 ret = strict_strtoull(cp + 1, base, (unsigned long long *)res); 259 if (!ret) 260 *res = -(*res); 261 } else { 262 ret = strict_strtoull(cp, base, (unsigned long long *)res); 263 } 264 265 return ret; 266 } 267 EXPORT_SYMBOL(strict_strtoll); 268 269 static int skip_atoi(const char **s) 270 { 271 int i = 0; 272 273 while (isdigit(**s)) 274 i = i*10 + *((*s)++) - '0'; 275 276 return i; 277 } 278 279 /* Decimal conversion is by far the most typical, and is used 280 * for /proc and /sys data. This directly impacts e.g. top performance 281 * with many processes running. We optimize it for speed 282 * using code from 283 * http://www.cs.uiowa.edu/~jones/bcd/decimal.html 284 * (with permission from the author, Douglas W. Jones). */ 285 286 /* Formats correctly any integer in [0,99999]. 287 * Outputs from one to five digits depending on input. 288 * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */ 289 static char *put_dec_trunc(char *buf, unsigned q) 290 { 291 unsigned d3, d2, d1, d0; 292 d1 = (q>>4) & 0xf; 293 d2 = (q>>8) & 0xf; 294 d3 = (q>>12); 295 296 d0 = 6*(d3 + d2 + d1) + (q & 0xf); 297 q = (d0 * 0xcd) >> 11; 298 d0 = d0 - 10*q; 299 *buf++ = d0 + '0'; /* least significant digit */ 300 d1 = q + 9*d3 + 5*d2 + d1; 301 if (d1 != 0) { 302 q = (d1 * 0xcd) >> 11; 303 d1 = d1 - 10*q; 304 *buf++ = d1 + '0'; /* next digit */ 305 306 d2 = q + 2*d2; 307 if ((d2 != 0) || (d3 != 0)) { 308 q = (d2 * 0xd) >> 7; 309 d2 = d2 - 10*q; 310 *buf++ = d2 + '0'; /* next digit */ 311 312 d3 = q + 4*d3; 313 if (d3 != 0) { 314 q = (d3 * 0xcd) >> 11; 315 d3 = d3 - 10*q; 316 *buf++ = d3 + '0'; /* next digit */ 317 if (q != 0) 318 *buf++ = q + '0'; /* most sign. digit */ 319 } 320 } 321 } 322 323 return buf; 324 } 325 /* Same with if's removed. Always emits five digits */ 326 static char *put_dec_full(char *buf, unsigned q) 327 { 328 /* BTW, if q is in [0,9999], 8-bit ints will be enough, */ 329 /* but anyway, gcc produces better code with full-sized ints */ 330 unsigned d3, d2, d1, d0; 331 d1 = (q>>4) & 0xf; 332 d2 = (q>>8) & 0xf; 333 d3 = (q>>12); 334 335 /* 336 * Possible ways to approx. divide by 10 337 * gcc -O2 replaces multiply with shifts and adds 338 * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386) 339 * (x * 0x67) >> 10: 1100111 340 * (x * 0x34) >> 9: 110100 - same 341 * (x * 0x1a) >> 8: 11010 - same 342 * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386) 343 */ 344 d0 = 6*(d3 + d2 + d1) + (q & 0xf); 345 q = (d0 * 0xcd) >> 11; 346 d0 = d0 - 10*q; 347 *buf++ = d0 + '0'; 348 d1 = q + 9*d3 + 5*d2 + d1; 349 q = (d1 * 0xcd) >> 11; 350 d1 = d1 - 10*q; 351 *buf++ = d1 + '0'; 352 353 d2 = q + 2*d2; 354 q = (d2 * 0xd) >> 7; 355 d2 = d2 - 10*q; 356 *buf++ = d2 + '0'; 357 358 d3 = q + 4*d3; 359 q = (d3 * 0xcd) >> 11; /* - shorter code */ 360 /* q = (d3 * 0x67) >> 10; - would also work */ 361 d3 = d3 - 10*q; 362 *buf++ = d3 + '0'; 363 *buf++ = q + '0'; 364 365 return buf; 366 } 367 /* No inlining helps gcc to use registers better */ 368 static noinline char *put_dec(char *buf, unsigned long long num) 369 { 370 while (1) { 371 unsigned rem; 372 if (num < 100000) 373 return put_dec_trunc(buf, num); 374 rem = do_div(num, 100000); 375 buf = put_dec_full(buf, rem); 376 } 377 } 378 379 #define ZEROPAD 1 /* pad with zero */ 380 #define SIGN 2 /* unsigned/signed long */ 381 #define PLUS 4 /* show plus */ 382 #define SPACE 8 /* space if plus */ 383 #define LEFT 16 /* left justified */ 384 #define SMALL 32 /* Must be 32 == 0x20 */ 385 #define SPECIAL 64 /* 0x */ 386 387 enum format_type { 388 FORMAT_TYPE_NONE, /* Just a string part */ 389 FORMAT_TYPE_WIDTH, 390 FORMAT_TYPE_PRECISION, 391 FORMAT_TYPE_CHAR, 392 FORMAT_TYPE_STR, 393 FORMAT_TYPE_PTR, 394 FORMAT_TYPE_PERCENT_CHAR, 395 FORMAT_TYPE_INVALID, 396 FORMAT_TYPE_LONG_LONG, 397 FORMAT_TYPE_ULONG, 398 FORMAT_TYPE_LONG, 399 FORMAT_TYPE_UBYTE, 400 FORMAT_TYPE_BYTE, 401 FORMAT_TYPE_USHORT, 402 FORMAT_TYPE_SHORT, 403 FORMAT_TYPE_UINT, 404 FORMAT_TYPE_INT, 405 FORMAT_TYPE_NRCHARS, 406 FORMAT_TYPE_SIZE_T, 407 FORMAT_TYPE_PTRDIFF 408 }; 409 410 struct printf_spec { 411 enum format_type type; 412 int flags; /* flags to number() */ 413 int field_width; /* width of output field */ 414 int base; 415 int precision; /* # of digits/chars */ 416 int qualifier; 417 }; 418 419 static char *number(char *buf, char *end, unsigned long long num, 420 struct printf_spec spec) 421 { 422 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */ 423 static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */ 424 425 char tmp[66]; 426 char sign; 427 char locase; 428 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10); 429 int i; 430 431 /* locase = 0 or 0x20. ORing digits or letters with 'locase' 432 * produces same digits or (maybe lowercased) letters */ 433 locase = (spec.flags & SMALL); 434 if (spec.flags & LEFT) 435 spec.flags &= ~ZEROPAD; 436 sign = 0; 437 if (spec.flags & SIGN) { 438 if ((signed long long)num < 0) { 439 sign = '-'; 440 num = -(signed long long)num; 441 spec.field_width--; 442 } else if (spec.flags & PLUS) { 443 sign = '+'; 444 spec.field_width--; 445 } else if (spec.flags & SPACE) { 446 sign = ' '; 447 spec.field_width--; 448 } 449 } 450 if (need_pfx) { 451 spec.field_width--; 452 if (spec.base == 16) 453 spec.field_width--; 454 } 455 456 /* generate full string in tmp[], in reverse order */ 457 i = 0; 458 if (num == 0) 459 tmp[i++] = '0'; 460 /* Generic code, for any base: 461 else do { 462 tmp[i++] = (digits[do_div(num,base)] | locase); 463 } while (num != 0); 464 */ 465 else if (spec.base != 10) { /* 8 or 16 */ 466 int mask = spec.base - 1; 467 int shift = 3; 468 469 if (spec.base == 16) 470 shift = 4; 471 do { 472 tmp[i++] = (digits[((unsigned char)num) & mask] | locase); 473 num >>= shift; 474 } while (num); 475 } else { /* base 10 */ 476 i = put_dec(tmp, num) - tmp; 477 } 478 479 /* printing 100 using %2d gives "100", not "00" */ 480 if (i > spec.precision) 481 spec.precision = i; 482 /* leading space padding */ 483 spec.field_width -= spec.precision; 484 if (!(spec.flags & (ZEROPAD+LEFT))) { 485 while (--spec.field_width >= 0) { 486 if (buf < end) 487 *buf = ' '; 488 ++buf; 489 } 490 } 491 /* sign */ 492 if (sign) { 493 if (buf < end) 494 *buf = sign; 495 ++buf; 496 } 497 /* "0x" / "0" prefix */ 498 if (need_pfx) { 499 if (buf < end) 500 *buf = '0'; 501 ++buf; 502 if (spec.base == 16) { 503 if (buf < end) 504 *buf = ('X' | locase); 505 ++buf; 506 } 507 } 508 /* zero or space padding */ 509 if (!(spec.flags & LEFT)) { 510 char c = (spec.flags & ZEROPAD) ? '0' : ' '; 511 while (--spec.field_width >= 0) { 512 if (buf < end) 513 *buf = c; 514 ++buf; 515 } 516 } 517 /* hmm even more zero padding? */ 518 while (i <= --spec.precision) { 519 if (buf < end) 520 *buf = '0'; 521 ++buf; 522 } 523 /* actual digits of result */ 524 while (--i >= 0) { 525 if (buf < end) 526 *buf = tmp[i]; 527 ++buf; 528 } 529 /* trailing space padding */ 530 while (--spec.field_width >= 0) { 531 if (buf < end) 532 *buf = ' '; 533 ++buf; 534 } 535 536 return buf; 537 } 538 539 static char *string(char *buf, char *end, const char *s, struct printf_spec spec) 540 { 541 int len, i; 542 543 if ((unsigned long)s < PAGE_SIZE) 544 s = "(null)"; 545 546 len = strnlen(s, spec.precision); 547 548 if (!(spec.flags & LEFT)) { 549 while (len < spec.field_width--) { 550 if (buf < end) 551 *buf = ' '; 552 ++buf; 553 } 554 } 555 for (i = 0; i < len; ++i) { 556 if (buf < end) 557 *buf = *s; 558 ++buf; ++s; 559 } 560 while (len < spec.field_width--) { 561 if (buf < end) 562 *buf = ' '; 563 ++buf; 564 } 565 566 return buf; 567 } 568 569 static char *symbol_string(char *buf, char *end, void *ptr, 570 struct printf_spec spec, char ext) 571 { 572 unsigned long value = (unsigned long) ptr; 573 #ifdef CONFIG_KALLSYMS 574 char sym[KSYM_SYMBOL_LEN]; 575 if (ext != 'f' && ext != 's') 576 sprint_symbol(sym, value); 577 else 578 kallsyms_lookup(value, NULL, NULL, NULL, sym); 579 580 return string(buf, end, sym, spec); 581 #else 582 spec.field_width = 2 * sizeof(void *); 583 spec.flags |= SPECIAL | SMALL | ZEROPAD; 584 spec.base = 16; 585 586 return number(buf, end, value, spec); 587 #endif 588 } 589 590 static char *resource_string(char *buf, char *end, struct resource *res, 591 struct printf_spec spec, const char *fmt) 592 { 593 #ifndef IO_RSRC_PRINTK_SIZE 594 #define IO_RSRC_PRINTK_SIZE 6 595 #endif 596 597 #ifndef MEM_RSRC_PRINTK_SIZE 598 #define MEM_RSRC_PRINTK_SIZE 10 599 #endif 600 struct printf_spec hex_spec = { 601 .base = 16, 602 .precision = -1, 603 .flags = SPECIAL | SMALL | ZEROPAD, 604 }; 605 struct printf_spec dec_spec = { 606 .base = 10, 607 .precision = -1, 608 .flags = 0, 609 }; 610 struct printf_spec str_spec = { 611 .field_width = -1, 612 .precision = 10, 613 .flags = LEFT, 614 }; 615 struct printf_spec flag_spec = { 616 .base = 16, 617 .precision = -1, 618 .flags = SPECIAL | SMALL, 619 }; 620 621 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) 622 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ 623 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) 624 #define FLAG_BUF_SIZE (2 * sizeof(res->flags)) 625 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref disabled]") 626 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]") 627 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 628 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; 629 630 char *p = sym, *pend = sym + sizeof(sym); 631 int size = -1, addr = 0; 632 int decode = (fmt[0] == 'R') ? 1 : 0; 633 634 if (res->flags & IORESOURCE_IO) { 635 size = IO_RSRC_PRINTK_SIZE; 636 addr = 1; 637 } else if (res->flags & IORESOURCE_MEM) { 638 size = MEM_RSRC_PRINTK_SIZE; 639 addr = 1; 640 } 641 642 *p++ = '['; 643 if (res->flags & IORESOURCE_IO) 644 p = string(p, pend, "io ", str_spec); 645 else if (res->flags & IORESOURCE_MEM) 646 p = string(p, pend, "mem ", str_spec); 647 else if (res->flags & IORESOURCE_IRQ) 648 p = string(p, pend, "irq ", str_spec); 649 else if (res->flags & IORESOURCE_DMA) 650 p = string(p, pend, "dma ", str_spec); 651 else { 652 p = string(p, pend, "??? ", str_spec); 653 decode = 0; 654 } 655 hex_spec.field_width = size; 656 p = number(p, pend, res->start, addr ? hex_spec : dec_spec); 657 if (res->start != res->end) { 658 *p++ = '-'; 659 p = number(p, pend, res->end, addr ? hex_spec : dec_spec); 660 } 661 if (decode) { 662 if (res->flags & IORESOURCE_MEM_64) 663 p = string(p, pend, " 64bit", str_spec); 664 if (res->flags & IORESOURCE_PREFETCH) 665 p = string(p, pend, " pref", str_spec); 666 if (res->flags & IORESOURCE_DISABLED) 667 p = string(p, pend, " disabled", str_spec); 668 } else { 669 p = string(p, pend, " flags ", str_spec); 670 p = number(p, pend, res->flags, flag_spec); 671 } 672 *p++ = ']'; 673 *p = '\0'; 674 675 return string(buf, end, sym, spec); 676 } 677 678 static char *mac_address_string(char *buf, char *end, u8 *addr, 679 struct printf_spec spec, const char *fmt) 680 { 681 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; 682 char *p = mac_addr; 683 int i; 684 char separator; 685 686 if (fmt[1] == 'F') { /* FDDI canonical format */ 687 separator = '-'; 688 } else { 689 separator = ':'; 690 } 691 692 for (i = 0; i < 6; i++) { 693 p = pack_hex_byte(p, addr[i]); 694 if (fmt[0] == 'M' && i != 5) 695 *p++ = separator; 696 } 697 *p = '\0'; 698 699 return string(buf, end, mac_addr, spec); 700 } 701 702 static char *ip4_string(char *p, const u8 *addr, const char *fmt) 703 { 704 int i; 705 bool leading_zeros = (fmt[0] == 'i'); 706 int index; 707 int step; 708 709 switch (fmt[2]) { 710 case 'h': 711 #ifdef __BIG_ENDIAN 712 index = 0; 713 step = 1; 714 #else 715 index = 3; 716 step = -1; 717 #endif 718 break; 719 case 'l': 720 index = 3; 721 step = -1; 722 break; 723 case 'n': 724 case 'b': 725 default: 726 index = 0; 727 step = 1; 728 break; 729 } 730 for (i = 0; i < 4; i++) { 731 char temp[3]; /* hold each IP quad in reverse order */ 732 int digits = put_dec_trunc(temp, addr[index]) - temp; 733 if (leading_zeros) { 734 if (digits < 3) 735 *p++ = '0'; 736 if (digits < 2) 737 *p++ = '0'; 738 } 739 /* reverse the digits in the quad */ 740 while (digits--) 741 *p++ = temp[digits]; 742 if (i < 3) 743 *p++ = '.'; 744 index += step; 745 } 746 *p = '\0'; 747 748 return p; 749 } 750 751 static char *ip6_compressed_string(char *p, const char *addr) 752 { 753 int i, j, range; 754 unsigned char zerolength[8]; 755 int longest = 1; 756 int colonpos = -1; 757 u16 word; 758 u8 hi, lo; 759 bool needcolon = false; 760 bool useIPv4; 761 struct in6_addr in6; 762 763 memcpy(&in6, addr, sizeof(struct in6_addr)); 764 765 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6); 766 767 memset(zerolength, 0, sizeof(zerolength)); 768 769 if (useIPv4) 770 range = 6; 771 else 772 range = 8; 773 774 /* find position of longest 0 run */ 775 for (i = 0; i < range; i++) { 776 for (j = i; j < range; j++) { 777 if (in6.s6_addr16[j] != 0) 778 break; 779 zerolength[i]++; 780 } 781 } 782 for (i = 0; i < range; i++) { 783 if (zerolength[i] > longest) { 784 longest = zerolength[i]; 785 colonpos = i; 786 } 787 } 788 789 /* emit address */ 790 for (i = 0; i < range; i++) { 791 if (i == colonpos) { 792 if (needcolon || i == 0) 793 *p++ = ':'; 794 *p++ = ':'; 795 needcolon = false; 796 i += longest - 1; 797 continue; 798 } 799 if (needcolon) { 800 *p++ = ':'; 801 needcolon = false; 802 } 803 /* hex u16 without leading 0s */ 804 word = ntohs(in6.s6_addr16[i]); 805 hi = word >> 8; 806 lo = word & 0xff; 807 if (hi) { 808 if (hi > 0x0f) 809 p = pack_hex_byte(p, hi); 810 else 811 *p++ = hex_asc_lo(hi); 812 p = pack_hex_byte(p, lo); 813 } 814 else if (lo > 0x0f) 815 p = pack_hex_byte(p, lo); 816 else 817 *p++ = hex_asc_lo(lo); 818 needcolon = true; 819 } 820 821 if (useIPv4) { 822 if (needcolon) 823 *p++ = ':'; 824 p = ip4_string(p, &in6.s6_addr[12], "I4"); 825 } 826 *p = '\0'; 827 828 return p; 829 } 830 831 static char *ip6_string(char *p, const char *addr, const char *fmt) 832 { 833 int i; 834 835 for (i = 0; i < 8; i++) { 836 p = pack_hex_byte(p, *addr++); 837 p = pack_hex_byte(p, *addr++); 838 if (fmt[0] == 'I' && i != 7) 839 *p++ = ':'; 840 } 841 *p = '\0'; 842 843 return p; 844 } 845 846 static char *ip6_addr_string(char *buf, char *end, const u8 *addr, 847 struct printf_spec spec, const char *fmt) 848 { 849 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 850 851 if (fmt[0] == 'I' && fmt[2] == 'c') 852 ip6_compressed_string(ip6_addr, addr); 853 else 854 ip6_string(ip6_addr, addr, fmt); 855 856 return string(buf, end, ip6_addr, spec); 857 } 858 859 static char *ip4_addr_string(char *buf, char *end, const u8 *addr, 860 struct printf_spec spec, const char *fmt) 861 { 862 char ip4_addr[sizeof("255.255.255.255")]; 863 864 ip4_string(ip4_addr, addr, fmt); 865 866 return string(buf, end, ip4_addr, spec); 867 } 868 869 static char *uuid_string(char *buf, char *end, const u8 *addr, 870 struct printf_spec spec, const char *fmt) 871 { 872 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")]; 873 char *p = uuid; 874 int i; 875 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15}; 876 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15}; 877 const u8 *index = be; 878 bool uc = false; 879 880 switch (*(++fmt)) { 881 case 'L': 882 uc = true; /* fall-through */ 883 case 'l': 884 index = le; 885 break; 886 case 'B': 887 uc = true; 888 break; 889 } 890 891 for (i = 0; i < 16; i++) { 892 p = pack_hex_byte(p, addr[index[i]]); 893 switch (i) { 894 case 3: 895 case 5: 896 case 7: 897 case 9: 898 *p++ = '-'; 899 break; 900 } 901 } 902 903 *p = 0; 904 905 if (uc) { 906 p = uuid; 907 do { 908 *p = toupper(*p); 909 } while (*(++p)); 910 } 911 912 return string(buf, end, uuid, spec); 913 } 914 915 /* 916 * Show a '%p' thing. A kernel extension is that the '%p' is followed 917 * by an extra set of alphanumeric characters that are extended format 918 * specifiers. 919 * 920 * Right now we handle: 921 * 922 * - 'F' For symbolic function descriptor pointers with offset 923 * - 'f' For simple symbolic function names without offset 924 * - 'S' For symbolic direct pointers with offset 925 * - 's' For symbolic direct pointers without offset 926 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 927 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 928 * - 'M' For a 6-byte MAC address, it prints the address in the 929 * usual colon-separated hex notation 930 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 931 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 932 * with a dash-separated hex notation 933 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 934 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 935 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 936 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 937 * IPv6 omits the colons (01020304...0f) 938 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 939 * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order 940 * - 'I6c' for IPv6 addresses printed as specified by 941 * http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-00 942 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 943 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 944 * Options for %pU are: 945 * b big endian lower case hex (default) 946 * B big endian UPPER case hex 947 * l little endian lower case hex 948 * L little endian UPPER case hex 949 * big endian output byte order is: 950 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 951 * little endian output byte order is: 952 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 953 * 954 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64 955 * function pointers are really function descriptors, which contain a 956 * pointer to the real address. 957 */ 958 static char *pointer(const char *fmt, char *buf, char *end, void *ptr, 959 struct printf_spec spec) 960 { 961 if (!ptr) 962 return string(buf, end, "(null)", spec); 963 964 switch (*fmt) { 965 case 'F': 966 case 'f': 967 ptr = dereference_function_descriptor(ptr); 968 /* Fallthrough */ 969 case 'S': 970 case 's': 971 return symbol_string(buf, end, ptr, spec, *fmt); 972 case 'R': 973 case 'r': 974 return resource_string(buf, end, ptr, spec, fmt); 975 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 976 case 'm': /* Contiguous: 000102030405 */ 977 /* [mM]F (FDDI, bit reversed) */ 978 return mac_address_string(buf, end, ptr, spec, fmt); 979 case 'I': /* Formatted IP supported 980 * 4: 1.2.3.4 981 * 6: 0001:0203:...:0708 982 * 6c: 1::708 or 1::1.2.3.4 983 */ 984 case 'i': /* Contiguous: 985 * 4: 001.002.003.004 986 * 6: 000102...0f 987 */ 988 switch (fmt[1]) { 989 case '6': 990 return ip6_addr_string(buf, end, ptr, spec, fmt); 991 case '4': 992 return ip4_addr_string(buf, end, ptr, spec, fmt); 993 } 994 break; 995 case 'U': 996 return uuid_string(buf, end, ptr, spec, fmt); 997 } 998 spec.flags |= SMALL; 999 if (spec.field_width == -1) { 1000 spec.field_width = 2*sizeof(void *); 1001 spec.flags |= ZEROPAD; 1002 } 1003 spec.base = 16; 1004 1005 return number(buf, end, (unsigned long) ptr, spec); 1006 } 1007 1008 /* 1009 * Helper function to decode printf style format. 1010 * Each call decode a token from the format and return the 1011 * number of characters read (or likely the delta where it wants 1012 * to go on the next call). 1013 * The decoded token is returned through the parameters 1014 * 1015 * 'h', 'l', or 'L' for integer fields 1016 * 'z' support added 23/7/1999 S.H. 1017 * 'z' changed to 'Z' --davidm 1/25/99 1018 * 't' added for ptrdiff_t 1019 * 1020 * @fmt: the format string 1021 * @type of the token returned 1022 * @flags: various flags such as +, -, # tokens.. 1023 * @field_width: overwritten width 1024 * @base: base of the number (octal, hex, ...) 1025 * @precision: precision of a number 1026 * @qualifier: qualifier of a number (long, size_t, ...) 1027 */ 1028 static int format_decode(const char *fmt, struct printf_spec *spec) 1029 { 1030 const char *start = fmt; 1031 1032 /* we finished early by reading the field width */ 1033 if (spec->type == FORMAT_TYPE_WIDTH) { 1034 if (spec->field_width < 0) { 1035 spec->field_width = -spec->field_width; 1036 spec->flags |= LEFT; 1037 } 1038 spec->type = FORMAT_TYPE_NONE; 1039 goto precision; 1040 } 1041 1042 /* we finished early by reading the precision */ 1043 if (spec->type == FORMAT_TYPE_PRECISION) { 1044 if (spec->precision < 0) 1045 spec->precision = 0; 1046 1047 spec->type = FORMAT_TYPE_NONE; 1048 goto qualifier; 1049 } 1050 1051 /* By default */ 1052 spec->type = FORMAT_TYPE_NONE; 1053 1054 for (; *fmt ; ++fmt) { 1055 if (*fmt == '%') 1056 break; 1057 } 1058 1059 /* Return the current non-format string */ 1060 if (fmt != start || !*fmt) 1061 return fmt - start; 1062 1063 /* Process flags */ 1064 spec->flags = 0; 1065 1066 while (1) { /* this also skips first '%' */ 1067 bool found = true; 1068 1069 ++fmt; 1070 1071 switch (*fmt) { 1072 case '-': spec->flags |= LEFT; break; 1073 case '+': spec->flags |= PLUS; break; 1074 case ' ': spec->flags |= SPACE; break; 1075 case '#': spec->flags |= SPECIAL; break; 1076 case '0': spec->flags |= ZEROPAD; break; 1077 default: found = false; 1078 } 1079 1080 if (!found) 1081 break; 1082 } 1083 1084 /* get field width */ 1085 spec->field_width = -1; 1086 1087 if (isdigit(*fmt)) 1088 spec->field_width = skip_atoi(&fmt); 1089 else if (*fmt == '*') { 1090 /* it's the next argument */ 1091 spec->type = FORMAT_TYPE_WIDTH; 1092 return ++fmt - start; 1093 } 1094 1095 precision: 1096 /* get the precision */ 1097 spec->precision = -1; 1098 if (*fmt == '.') { 1099 ++fmt; 1100 if (isdigit(*fmt)) { 1101 spec->precision = skip_atoi(&fmt); 1102 if (spec->precision < 0) 1103 spec->precision = 0; 1104 } else if (*fmt == '*') { 1105 /* it's the next argument */ 1106 spec->type = FORMAT_TYPE_PRECISION; 1107 return ++fmt - start; 1108 } 1109 } 1110 1111 qualifier: 1112 /* get the conversion qualifier */ 1113 spec->qualifier = -1; 1114 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' || 1115 TOLOWER(*fmt) == 'z' || *fmt == 't') { 1116 spec->qualifier = *fmt++; 1117 if (unlikely(spec->qualifier == *fmt)) { 1118 if (spec->qualifier == 'l') { 1119 spec->qualifier = 'L'; 1120 ++fmt; 1121 } else if (spec->qualifier == 'h') { 1122 spec->qualifier = 'H'; 1123 ++fmt; 1124 } 1125 } 1126 } 1127 1128 /* default base */ 1129 spec->base = 10; 1130 switch (*fmt) { 1131 case 'c': 1132 spec->type = FORMAT_TYPE_CHAR; 1133 return ++fmt - start; 1134 1135 case 's': 1136 spec->type = FORMAT_TYPE_STR; 1137 return ++fmt - start; 1138 1139 case 'p': 1140 spec->type = FORMAT_TYPE_PTR; 1141 return fmt - start; 1142 /* skip alnum */ 1143 1144 case 'n': 1145 spec->type = FORMAT_TYPE_NRCHARS; 1146 return ++fmt - start; 1147 1148 case '%': 1149 spec->type = FORMAT_TYPE_PERCENT_CHAR; 1150 return ++fmt - start; 1151 1152 /* integer number formats - set up the flags and "break" */ 1153 case 'o': 1154 spec->base = 8; 1155 break; 1156 1157 case 'x': 1158 spec->flags |= SMALL; 1159 1160 case 'X': 1161 spec->base = 16; 1162 break; 1163 1164 case 'd': 1165 case 'i': 1166 spec->flags |= SIGN; 1167 case 'u': 1168 break; 1169 1170 default: 1171 spec->type = FORMAT_TYPE_INVALID; 1172 return fmt - start; 1173 } 1174 1175 if (spec->qualifier == 'L') 1176 spec->type = FORMAT_TYPE_LONG_LONG; 1177 else if (spec->qualifier == 'l') { 1178 if (spec->flags & SIGN) 1179 spec->type = FORMAT_TYPE_LONG; 1180 else 1181 spec->type = FORMAT_TYPE_ULONG; 1182 } else if (TOLOWER(spec->qualifier) == 'z') { 1183 spec->type = FORMAT_TYPE_SIZE_T; 1184 } else if (spec->qualifier == 't') { 1185 spec->type = FORMAT_TYPE_PTRDIFF; 1186 } else if (spec->qualifier == 'H') { 1187 if (spec->flags & SIGN) 1188 spec->type = FORMAT_TYPE_BYTE; 1189 else 1190 spec->type = FORMAT_TYPE_UBYTE; 1191 } else if (spec->qualifier == 'h') { 1192 if (spec->flags & SIGN) 1193 spec->type = FORMAT_TYPE_SHORT; 1194 else 1195 spec->type = FORMAT_TYPE_USHORT; 1196 } else { 1197 if (spec->flags & SIGN) 1198 spec->type = FORMAT_TYPE_INT; 1199 else 1200 spec->type = FORMAT_TYPE_UINT; 1201 } 1202 1203 return ++fmt - start; 1204 } 1205 1206 /** 1207 * vsnprintf - Format a string and place it in a buffer 1208 * @buf: The buffer to place the result into 1209 * @size: The size of the buffer, including the trailing null space 1210 * @fmt: The format string to use 1211 * @args: Arguments for the format string 1212 * 1213 * This function follows C99 vsnprintf, but has some extensions: 1214 * %pS output the name of a text symbol with offset 1215 * %ps output the name of a text symbol without offset 1216 * %pF output the name of a function pointer with its offset 1217 * %pf output the name of a function pointer without its offset 1218 * %pR output the address range in a struct resource with decoded flags 1219 * %pr output the address range in a struct resource with raw flags 1220 * %pM output a 6-byte MAC address with colons 1221 * %pm output a 6-byte MAC address without colons 1222 * %pI4 print an IPv4 address without leading zeros 1223 * %pi4 print an IPv4 address with leading zeros 1224 * %pI6 print an IPv6 address with colons 1225 * %pi6 print an IPv6 address without colons 1226 * %pI6c print an IPv6 address as specified by 1227 * http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-00 1228 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper 1229 * case. 1230 * %n is ignored 1231 * 1232 * The return value is the number of characters which would 1233 * be generated for the given input, excluding the trailing 1234 * '\0', as per ISO C99. If you want to have the exact 1235 * number of characters written into @buf as return value 1236 * (not including the trailing '\0'), use vscnprintf(). If the 1237 * return is greater than or equal to @size, the resulting 1238 * string is truncated. 1239 * 1240 * Call this function if you are already dealing with a va_list. 1241 * You probably want snprintf() instead. 1242 */ 1243 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) 1244 { 1245 unsigned long long num; 1246 char *str, *end; 1247 struct printf_spec spec = {0}; 1248 1249 /* Reject out-of-range values early. Large positive sizes are 1250 used for unknown buffer sizes. */ 1251 if (WARN_ON_ONCE((int) size < 0)) 1252 return 0; 1253 1254 str = buf; 1255 end = buf + size; 1256 1257 /* Make sure end is always >= buf */ 1258 if (end < buf) { 1259 end = ((void *)-1); 1260 size = end - buf; 1261 } 1262 1263 while (*fmt) { 1264 const char *old_fmt = fmt; 1265 int read = format_decode(fmt, &spec); 1266 1267 fmt += read; 1268 1269 switch (spec.type) { 1270 case FORMAT_TYPE_NONE: { 1271 int copy = read; 1272 if (str < end) { 1273 if (copy > end - str) 1274 copy = end - str; 1275 memcpy(str, old_fmt, copy); 1276 } 1277 str += read; 1278 break; 1279 } 1280 1281 case FORMAT_TYPE_WIDTH: 1282 spec.field_width = va_arg(args, int); 1283 break; 1284 1285 case FORMAT_TYPE_PRECISION: 1286 spec.precision = va_arg(args, int); 1287 break; 1288 1289 case FORMAT_TYPE_CHAR: { 1290 char c; 1291 1292 if (!(spec.flags & LEFT)) { 1293 while (--spec.field_width > 0) { 1294 if (str < end) 1295 *str = ' '; 1296 ++str; 1297 1298 } 1299 } 1300 c = (unsigned char) va_arg(args, int); 1301 if (str < end) 1302 *str = c; 1303 ++str; 1304 while (--spec.field_width > 0) { 1305 if (str < end) 1306 *str = ' '; 1307 ++str; 1308 } 1309 break; 1310 } 1311 1312 case FORMAT_TYPE_STR: 1313 str = string(str, end, va_arg(args, char *), spec); 1314 break; 1315 1316 case FORMAT_TYPE_PTR: 1317 str = pointer(fmt+1, str, end, va_arg(args, void *), 1318 spec); 1319 while (isalnum(*fmt)) 1320 fmt++; 1321 break; 1322 1323 case FORMAT_TYPE_PERCENT_CHAR: 1324 if (str < end) 1325 *str = '%'; 1326 ++str; 1327 break; 1328 1329 case FORMAT_TYPE_INVALID: 1330 if (str < end) 1331 *str = '%'; 1332 ++str; 1333 break; 1334 1335 case FORMAT_TYPE_NRCHARS: { 1336 int qualifier = spec.qualifier; 1337 1338 if (qualifier == 'l') { 1339 long *ip = va_arg(args, long *); 1340 *ip = (str - buf); 1341 } else if (TOLOWER(qualifier) == 'z') { 1342 size_t *ip = va_arg(args, size_t *); 1343 *ip = (str - buf); 1344 } else { 1345 int *ip = va_arg(args, int *); 1346 *ip = (str - buf); 1347 } 1348 break; 1349 } 1350 1351 default: 1352 switch (spec.type) { 1353 case FORMAT_TYPE_LONG_LONG: 1354 num = va_arg(args, long long); 1355 break; 1356 case FORMAT_TYPE_ULONG: 1357 num = va_arg(args, unsigned long); 1358 break; 1359 case FORMAT_TYPE_LONG: 1360 num = va_arg(args, long); 1361 break; 1362 case FORMAT_TYPE_SIZE_T: 1363 num = va_arg(args, size_t); 1364 break; 1365 case FORMAT_TYPE_PTRDIFF: 1366 num = va_arg(args, ptrdiff_t); 1367 break; 1368 case FORMAT_TYPE_UBYTE: 1369 num = (unsigned char) va_arg(args, int); 1370 break; 1371 case FORMAT_TYPE_BYTE: 1372 num = (signed char) va_arg(args, int); 1373 break; 1374 case FORMAT_TYPE_USHORT: 1375 num = (unsigned short) va_arg(args, int); 1376 break; 1377 case FORMAT_TYPE_SHORT: 1378 num = (short) va_arg(args, int); 1379 break; 1380 case FORMAT_TYPE_INT: 1381 num = (int) va_arg(args, int); 1382 break; 1383 default: 1384 num = va_arg(args, unsigned int); 1385 } 1386 1387 str = number(str, end, num, spec); 1388 } 1389 } 1390 1391 if (size > 0) { 1392 if (str < end) 1393 *str = '\0'; 1394 else 1395 end[-1] = '\0'; 1396 } 1397 1398 /* the trailing null byte doesn't count towards the total */ 1399 return str-buf; 1400 1401 } 1402 EXPORT_SYMBOL(vsnprintf); 1403 1404 /** 1405 * vscnprintf - Format a string and place it in a buffer 1406 * @buf: The buffer to place the result into 1407 * @size: The size of the buffer, including the trailing null space 1408 * @fmt: The format string to use 1409 * @args: Arguments for the format string 1410 * 1411 * The return value is the number of characters which have been written into 1412 * the @buf not including the trailing '\0'. If @size is <= 0 the function 1413 * returns 0. 1414 * 1415 * Call this function if you are already dealing with a va_list. 1416 * You probably want scnprintf() instead. 1417 * 1418 * See the vsnprintf() documentation for format string extensions over C99. 1419 */ 1420 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 1421 { 1422 int i; 1423 1424 i = vsnprintf(buf, size, fmt, args); 1425 1426 return (i >= size) ? (size - 1) : i; 1427 } 1428 EXPORT_SYMBOL(vscnprintf); 1429 1430 /** 1431 * snprintf - Format a string and place it in a buffer 1432 * @buf: The buffer to place the result into 1433 * @size: The size of the buffer, including the trailing null space 1434 * @fmt: The format string to use 1435 * @...: Arguments for the format string 1436 * 1437 * The return value is the number of characters which would be 1438 * generated for the given input, excluding the trailing null, 1439 * as per ISO C99. If the return is greater than or equal to 1440 * @size, the resulting string is truncated. 1441 * 1442 * See the vsnprintf() documentation for format string extensions over C99. 1443 */ 1444 int snprintf(char *buf, size_t size, const char *fmt, ...) 1445 { 1446 va_list args; 1447 int i; 1448 1449 va_start(args, fmt); 1450 i = vsnprintf(buf, size, fmt, args); 1451 va_end(args); 1452 1453 return i; 1454 } 1455 EXPORT_SYMBOL(snprintf); 1456 1457 /** 1458 * scnprintf - Format a string and place it in a buffer 1459 * @buf: The buffer to place the result into 1460 * @size: The size of the buffer, including the trailing null space 1461 * @fmt: The format string to use 1462 * @...: Arguments for the format string 1463 * 1464 * The return value is the number of characters written into @buf not including 1465 * the trailing '\0'. If @size is <= 0 the function returns 0. 1466 */ 1467 1468 int scnprintf(char *buf, size_t size, const char *fmt, ...) 1469 { 1470 va_list args; 1471 int i; 1472 1473 va_start(args, fmt); 1474 i = vsnprintf(buf, size, fmt, args); 1475 va_end(args); 1476 1477 return (i >= size) ? (size - 1) : i; 1478 } 1479 EXPORT_SYMBOL(scnprintf); 1480 1481 /** 1482 * vsprintf - Format a string and place it in a buffer 1483 * @buf: The buffer to place the result into 1484 * @fmt: The format string to use 1485 * @args: Arguments for the format string 1486 * 1487 * The function returns the number of characters written 1488 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid 1489 * buffer overflows. 1490 * 1491 * Call this function if you are already dealing with a va_list. 1492 * You probably want sprintf() instead. 1493 * 1494 * See the vsnprintf() documentation for format string extensions over C99. 1495 */ 1496 int vsprintf(char *buf, const char *fmt, va_list args) 1497 { 1498 return vsnprintf(buf, INT_MAX, fmt, args); 1499 } 1500 EXPORT_SYMBOL(vsprintf); 1501 1502 /** 1503 * sprintf - Format a string and place it in a buffer 1504 * @buf: The buffer to place the result into 1505 * @fmt: The format string to use 1506 * @...: Arguments for the format string 1507 * 1508 * The function returns the number of characters written 1509 * into @buf. Use snprintf() or scnprintf() in order to avoid 1510 * buffer overflows. 1511 * 1512 * See the vsnprintf() documentation for format string extensions over C99. 1513 */ 1514 int sprintf(char *buf, const char *fmt, ...) 1515 { 1516 va_list args; 1517 int i; 1518 1519 va_start(args, fmt); 1520 i = vsnprintf(buf, INT_MAX, fmt, args); 1521 va_end(args); 1522 1523 return i; 1524 } 1525 EXPORT_SYMBOL(sprintf); 1526 1527 #ifdef CONFIG_BINARY_PRINTF 1528 /* 1529 * bprintf service: 1530 * vbin_printf() - VA arguments to binary data 1531 * bstr_printf() - Binary data to text string 1532 */ 1533 1534 /** 1535 * vbin_printf - Parse a format string and place args' binary value in a buffer 1536 * @bin_buf: The buffer to place args' binary value 1537 * @size: The size of the buffer(by words(32bits), not characters) 1538 * @fmt: The format string to use 1539 * @args: Arguments for the format string 1540 * 1541 * The format follows C99 vsnprintf, except %n is ignored, and its argument 1542 * is skiped. 1543 * 1544 * The return value is the number of words(32bits) which would be generated for 1545 * the given input. 1546 * 1547 * NOTE: 1548 * If the return value is greater than @size, the resulting bin_buf is NOT 1549 * valid for bstr_printf(). 1550 */ 1551 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args) 1552 { 1553 struct printf_spec spec = {0}; 1554 char *str, *end; 1555 1556 str = (char *)bin_buf; 1557 end = (char *)(bin_buf + size); 1558 1559 #define save_arg(type) \ 1560 do { \ 1561 if (sizeof(type) == 8) { \ 1562 unsigned long long value; \ 1563 str = PTR_ALIGN(str, sizeof(u32)); \ 1564 value = va_arg(args, unsigned long long); \ 1565 if (str + sizeof(type) <= end) { \ 1566 *(u32 *)str = *(u32 *)&value; \ 1567 *(u32 *)(str + 4) = *((u32 *)&value + 1); \ 1568 } \ 1569 } else { \ 1570 unsigned long value; \ 1571 str = PTR_ALIGN(str, sizeof(type)); \ 1572 value = va_arg(args, int); \ 1573 if (str + sizeof(type) <= end) \ 1574 *(typeof(type) *)str = (type)value; \ 1575 } \ 1576 str += sizeof(type); \ 1577 } while (0) 1578 1579 while (*fmt) { 1580 int read = format_decode(fmt, &spec); 1581 1582 fmt += read; 1583 1584 switch (spec.type) { 1585 case FORMAT_TYPE_NONE: 1586 case FORMAT_TYPE_INVALID: 1587 case FORMAT_TYPE_PERCENT_CHAR: 1588 break; 1589 1590 case FORMAT_TYPE_WIDTH: 1591 case FORMAT_TYPE_PRECISION: 1592 save_arg(int); 1593 break; 1594 1595 case FORMAT_TYPE_CHAR: 1596 save_arg(char); 1597 break; 1598 1599 case FORMAT_TYPE_STR: { 1600 const char *save_str = va_arg(args, char *); 1601 size_t len; 1602 1603 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE 1604 || (unsigned long)save_str < PAGE_SIZE) 1605 save_str = "(null)"; 1606 len = strlen(save_str) + 1; 1607 if (str + len < end) 1608 memcpy(str, save_str, len); 1609 str += len; 1610 break; 1611 } 1612 1613 case FORMAT_TYPE_PTR: 1614 save_arg(void *); 1615 /* skip all alphanumeric pointer suffixes */ 1616 while (isalnum(*fmt)) 1617 fmt++; 1618 break; 1619 1620 case FORMAT_TYPE_NRCHARS: { 1621 /* skip %n 's argument */ 1622 int qualifier = spec.qualifier; 1623 void *skip_arg; 1624 if (qualifier == 'l') 1625 skip_arg = va_arg(args, long *); 1626 else if (TOLOWER(qualifier) == 'z') 1627 skip_arg = va_arg(args, size_t *); 1628 else 1629 skip_arg = va_arg(args, int *); 1630 break; 1631 } 1632 1633 default: 1634 switch (spec.type) { 1635 1636 case FORMAT_TYPE_LONG_LONG: 1637 save_arg(long long); 1638 break; 1639 case FORMAT_TYPE_ULONG: 1640 case FORMAT_TYPE_LONG: 1641 save_arg(unsigned long); 1642 break; 1643 case FORMAT_TYPE_SIZE_T: 1644 save_arg(size_t); 1645 break; 1646 case FORMAT_TYPE_PTRDIFF: 1647 save_arg(ptrdiff_t); 1648 break; 1649 case FORMAT_TYPE_UBYTE: 1650 case FORMAT_TYPE_BYTE: 1651 save_arg(char); 1652 break; 1653 case FORMAT_TYPE_USHORT: 1654 case FORMAT_TYPE_SHORT: 1655 save_arg(short); 1656 break; 1657 default: 1658 save_arg(int); 1659 } 1660 } 1661 } 1662 1663 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 1664 #undef save_arg 1665 } 1666 EXPORT_SYMBOL_GPL(vbin_printf); 1667 1668 /** 1669 * bstr_printf - Format a string from binary arguments and place it in a buffer 1670 * @buf: The buffer to place the result into 1671 * @size: The size of the buffer, including the trailing null space 1672 * @fmt: The format string to use 1673 * @bin_buf: Binary arguments for the format string 1674 * 1675 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 1676 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 1677 * a binary buffer that generated by vbin_printf. 1678 * 1679 * The format follows C99 vsnprintf, but has some extensions: 1680 * see vsnprintf comment for details. 1681 * 1682 * The return value is the number of characters which would 1683 * be generated for the given input, excluding the trailing 1684 * '\0', as per ISO C99. If you want to have the exact 1685 * number of characters written into @buf as return value 1686 * (not including the trailing '\0'), use vscnprintf(). If the 1687 * return is greater than or equal to @size, the resulting 1688 * string is truncated. 1689 */ 1690 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) 1691 { 1692 struct printf_spec spec = {0}; 1693 char *str, *end; 1694 const char *args = (const char *)bin_buf; 1695 1696 if (WARN_ON_ONCE((int) size < 0)) 1697 return 0; 1698 1699 str = buf; 1700 end = buf + size; 1701 1702 #define get_arg(type) \ 1703 ({ \ 1704 typeof(type) value; \ 1705 if (sizeof(type) == 8) { \ 1706 args = PTR_ALIGN(args, sizeof(u32)); \ 1707 *(u32 *)&value = *(u32 *)args; \ 1708 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 1709 } else { \ 1710 args = PTR_ALIGN(args, sizeof(type)); \ 1711 value = *(typeof(type) *)args; \ 1712 } \ 1713 args += sizeof(type); \ 1714 value; \ 1715 }) 1716 1717 /* Make sure end is always >= buf */ 1718 if (end < buf) { 1719 end = ((void *)-1); 1720 size = end - buf; 1721 } 1722 1723 while (*fmt) { 1724 const char *old_fmt = fmt; 1725 int read = format_decode(fmt, &spec); 1726 1727 fmt += read; 1728 1729 switch (spec.type) { 1730 case FORMAT_TYPE_NONE: { 1731 int copy = read; 1732 if (str < end) { 1733 if (copy > end - str) 1734 copy = end - str; 1735 memcpy(str, old_fmt, copy); 1736 } 1737 str += read; 1738 break; 1739 } 1740 1741 case FORMAT_TYPE_WIDTH: 1742 spec.field_width = get_arg(int); 1743 break; 1744 1745 case FORMAT_TYPE_PRECISION: 1746 spec.precision = get_arg(int); 1747 break; 1748 1749 case FORMAT_TYPE_CHAR: { 1750 char c; 1751 1752 if (!(spec.flags & LEFT)) { 1753 while (--spec.field_width > 0) { 1754 if (str < end) 1755 *str = ' '; 1756 ++str; 1757 } 1758 } 1759 c = (unsigned char) get_arg(char); 1760 if (str < end) 1761 *str = c; 1762 ++str; 1763 while (--spec.field_width > 0) { 1764 if (str < end) 1765 *str = ' '; 1766 ++str; 1767 } 1768 break; 1769 } 1770 1771 case FORMAT_TYPE_STR: { 1772 const char *str_arg = args; 1773 args += strlen(str_arg) + 1; 1774 str = string(str, end, (char *)str_arg, spec); 1775 break; 1776 } 1777 1778 case FORMAT_TYPE_PTR: 1779 str = pointer(fmt+1, str, end, get_arg(void *), spec); 1780 while (isalnum(*fmt)) 1781 fmt++; 1782 break; 1783 1784 case FORMAT_TYPE_PERCENT_CHAR: 1785 case FORMAT_TYPE_INVALID: 1786 if (str < end) 1787 *str = '%'; 1788 ++str; 1789 break; 1790 1791 case FORMAT_TYPE_NRCHARS: 1792 /* skip */ 1793 break; 1794 1795 default: { 1796 unsigned long long num; 1797 1798 switch (spec.type) { 1799 1800 case FORMAT_TYPE_LONG_LONG: 1801 num = get_arg(long long); 1802 break; 1803 case FORMAT_TYPE_ULONG: 1804 case FORMAT_TYPE_LONG: 1805 num = get_arg(unsigned long); 1806 break; 1807 case FORMAT_TYPE_SIZE_T: 1808 num = get_arg(size_t); 1809 break; 1810 case FORMAT_TYPE_PTRDIFF: 1811 num = get_arg(ptrdiff_t); 1812 break; 1813 case FORMAT_TYPE_UBYTE: 1814 num = get_arg(unsigned char); 1815 break; 1816 case FORMAT_TYPE_BYTE: 1817 num = get_arg(signed char); 1818 break; 1819 case FORMAT_TYPE_USHORT: 1820 num = get_arg(unsigned short); 1821 break; 1822 case FORMAT_TYPE_SHORT: 1823 num = get_arg(short); 1824 break; 1825 case FORMAT_TYPE_UINT: 1826 num = get_arg(unsigned int); 1827 break; 1828 default: 1829 num = get_arg(int); 1830 } 1831 1832 str = number(str, end, num, spec); 1833 } /* default: */ 1834 } /* switch(spec.type) */ 1835 } /* while(*fmt) */ 1836 1837 if (size > 0) { 1838 if (str < end) 1839 *str = '\0'; 1840 else 1841 end[-1] = '\0'; 1842 } 1843 1844 #undef get_arg 1845 1846 /* the trailing null byte doesn't count towards the total */ 1847 return str - buf; 1848 } 1849 EXPORT_SYMBOL_GPL(bstr_printf); 1850 1851 /** 1852 * bprintf - Parse a format string and place args' binary value in a buffer 1853 * @bin_buf: The buffer to place args' binary value 1854 * @size: The size of the buffer(by words(32bits), not characters) 1855 * @fmt: The format string to use 1856 * @...: Arguments for the format string 1857 * 1858 * The function returns the number of words(u32) written 1859 * into @bin_buf. 1860 */ 1861 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) 1862 { 1863 va_list args; 1864 int ret; 1865 1866 va_start(args, fmt); 1867 ret = vbin_printf(bin_buf, size, fmt, args); 1868 va_end(args); 1869 1870 return ret; 1871 } 1872 EXPORT_SYMBOL_GPL(bprintf); 1873 1874 #endif /* CONFIG_BINARY_PRINTF */ 1875 1876 /** 1877 * vsscanf - Unformat a buffer into a list of arguments 1878 * @buf: input buffer 1879 * @fmt: format of buffer 1880 * @args: arguments 1881 */ 1882 int vsscanf(const char *buf, const char *fmt, va_list args) 1883 { 1884 const char *str = buf; 1885 char *next; 1886 char digit; 1887 int num = 0; 1888 int qualifier, base, field_width; 1889 bool is_sign; 1890 1891 while (*fmt && *str) { 1892 /* skip any white space in format */ 1893 /* white space in format matchs any amount of 1894 * white space, including none, in the input. 1895 */ 1896 if (isspace(*fmt)) { 1897 fmt = skip_spaces(++fmt); 1898 str = skip_spaces(str); 1899 } 1900 1901 /* anything that is not a conversion must match exactly */ 1902 if (*fmt != '%' && *fmt) { 1903 if (*fmt++ != *str++) 1904 break; 1905 continue; 1906 } 1907 1908 if (!*fmt) 1909 break; 1910 ++fmt; 1911 1912 /* skip this conversion. 1913 * advance both strings to next white space 1914 */ 1915 if (*fmt == '*') { 1916 while (!isspace(*fmt) && *fmt != '%' && *fmt) 1917 fmt++; 1918 while (!isspace(*str) && *str) 1919 str++; 1920 continue; 1921 } 1922 1923 /* get field width */ 1924 field_width = -1; 1925 if (isdigit(*fmt)) 1926 field_width = skip_atoi(&fmt); 1927 1928 /* get conversion qualifier */ 1929 qualifier = -1; 1930 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' || 1931 TOLOWER(*fmt) == 'z') { 1932 qualifier = *fmt++; 1933 if (unlikely(qualifier == *fmt)) { 1934 if (qualifier == 'h') { 1935 qualifier = 'H'; 1936 fmt++; 1937 } else if (qualifier == 'l') { 1938 qualifier = 'L'; 1939 fmt++; 1940 } 1941 } 1942 } 1943 1944 if (!*fmt || !*str) 1945 break; 1946 1947 base = 10; 1948 is_sign = 0; 1949 1950 switch (*fmt++) { 1951 case 'c': 1952 { 1953 char *s = (char *)va_arg(args, char*); 1954 if (field_width == -1) 1955 field_width = 1; 1956 do { 1957 *s++ = *str++; 1958 } while (--field_width > 0 && *str); 1959 num++; 1960 } 1961 continue; 1962 case 's': 1963 { 1964 char *s = (char *)va_arg(args, char *); 1965 if (field_width == -1) 1966 field_width = INT_MAX; 1967 /* first, skip leading white space in buffer */ 1968 str = skip_spaces(str); 1969 1970 /* now copy until next white space */ 1971 while (*str && !isspace(*str) && field_width--) 1972 *s++ = *str++; 1973 *s = '\0'; 1974 num++; 1975 } 1976 continue; 1977 case 'n': 1978 /* return number of characters read so far */ 1979 { 1980 int *i = (int *)va_arg(args, int*); 1981 *i = str - buf; 1982 } 1983 continue; 1984 case 'o': 1985 base = 8; 1986 break; 1987 case 'x': 1988 case 'X': 1989 base = 16; 1990 break; 1991 case 'i': 1992 base = 0; 1993 case 'd': 1994 is_sign = 1; 1995 case 'u': 1996 break; 1997 case '%': 1998 /* looking for '%' in str */ 1999 if (*str++ != '%') 2000 return num; 2001 continue; 2002 default: 2003 /* invalid format; stop here */ 2004 return num; 2005 } 2006 2007 /* have some sort of integer conversion. 2008 * first, skip white space in buffer. 2009 */ 2010 str = skip_spaces(str); 2011 2012 digit = *str; 2013 if (is_sign && digit == '-') 2014 digit = *(str + 1); 2015 2016 if (!digit 2017 || (base == 16 && !isxdigit(digit)) 2018 || (base == 10 && !isdigit(digit)) 2019 || (base == 8 && (!isdigit(digit) || digit > '7')) 2020 || (base == 0 && !isdigit(digit))) 2021 break; 2022 2023 switch (qualifier) { 2024 case 'H': /* that's 'hh' in format */ 2025 if (is_sign) { 2026 signed char *s = (signed char *)va_arg(args, signed char *); 2027 *s = (signed char)simple_strtol(str, &next, base); 2028 } else { 2029 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *); 2030 *s = (unsigned char)simple_strtoul(str, &next, base); 2031 } 2032 break; 2033 case 'h': 2034 if (is_sign) { 2035 short *s = (short *)va_arg(args, short *); 2036 *s = (short)simple_strtol(str, &next, base); 2037 } else { 2038 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *); 2039 *s = (unsigned short)simple_strtoul(str, &next, base); 2040 } 2041 break; 2042 case 'l': 2043 if (is_sign) { 2044 long *l = (long *)va_arg(args, long *); 2045 *l = simple_strtol(str, &next, base); 2046 } else { 2047 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *); 2048 *l = simple_strtoul(str, &next, base); 2049 } 2050 break; 2051 case 'L': 2052 if (is_sign) { 2053 long long *l = (long long *)va_arg(args, long long *); 2054 *l = simple_strtoll(str, &next, base); 2055 } else { 2056 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *); 2057 *l = simple_strtoull(str, &next, base); 2058 } 2059 break; 2060 case 'Z': 2061 case 'z': 2062 { 2063 size_t *s = (size_t *)va_arg(args, size_t *); 2064 *s = (size_t)simple_strtoul(str, &next, base); 2065 } 2066 break; 2067 default: 2068 if (is_sign) { 2069 int *i = (int *)va_arg(args, int *); 2070 *i = (int)simple_strtol(str, &next, base); 2071 } else { 2072 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*); 2073 *i = (unsigned int)simple_strtoul(str, &next, base); 2074 } 2075 break; 2076 } 2077 num++; 2078 2079 if (!next) 2080 break; 2081 str = next; 2082 } 2083 2084 /* 2085 * Now we've come all the way through so either the input string or the 2086 * format ended. In the former case, there can be a %n at the current 2087 * position in the format that needs to be filled. 2088 */ 2089 if (*fmt == '%' && *(fmt + 1) == 'n') { 2090 int *p = (int *)va_arg(args, int *); 2091 *p = str - buf; 2092 } 2093 2094 return num; 2095 } 2096 EXPORT_SYMBOL(vsscanf); 2097 2098 /** 2099 * sscanf - Unformat a buffer into a list of arguments 2100 * @buf: input buffer 2101 * @fmt: formatting of buffer 2102 * @...: resulting arguments 2103 */ 2104 int sscanf(const char *buf, const char *fmt, ...) 2105 { 2106 va_list args; 2107 int i; 2108 2109 va_start(args, fmt); 2110 i = vsscanf(buf, fmt, args); 2111 va_end(args); 2112 2113 return i; 2114 } 2115 EXPORT_SYMBOL(sscanf); 2116