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 /* use lowercase in hex (must be 32 == 0x20) */ 385 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */ 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 u16 type; 412 s16 field_width; /* width of output field */ 413 u8 flags; /* flags to number() */ 414 u8 base; 415 s8 precision; /* # of digits/chars */ 416 u8 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 static const struct printf_spec io_spec = { 601 .base = 16, 602 .field_width = IO_RSRC_PRINTK_SIZE, 603 .precision = -1, 604 .flags = SPECIAL | SMALL | ZEROPAD, 605 }; 606 static const struct printf_spec mem_spec = { 607 .base = 16, 608 .field_width = MEM_RSRC_PRINTK_SIZE, 609 .precision = -1, 610 .flags = SPECIAL | SMALL | ZEROPAD, 611 }; 612 static const struct printf_spec bus_spec = { 613 .base = 16, 614 .field_width = 2, 615 .precision = -1, 616 .flags = SMALL | ZEROPAD, 617 }; 618 static const struct printf_spec dec_spec = { 619 .base = 10, 620 .precision = -1, 621 .flags = 0, 622 }; 623 static const struct printf_spec str_spec = { 624 .field_width = -1, 625 .precision = 10, 626 .flags = LEFT, 627 }; 628 static const struct printf_spec flag_spec = { 629 .base = 16, 630 .precision = -1, 631 .flags = SPECIAL | SMALL, 632 }; 633 634 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) 635 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ 636 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) 637 #define FLAG_BUF_SIZE (2 * sizeof(res->flags)) 638 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") 639 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]") 640 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 641 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; 642 643 char *p = sym, *pend = sym + sizeof(sym); 644 int decode = (fmt[0] == 'R') ? 1 : 0; 645 const struct printf_spec *specp; 646 647 *p++ = '['; 648 if (res->flags & IORESOURCE_IO) { 649 p = string(p, pend, "io ", str_spec); 650 specp = &io_spec; 651 } else if (res->flags & IORESOURCE_MEM) { 652 p = string(p, pend, "mem ", str_spec); 653 specp = &mem_spec; 654 } else if (res->flags & IORESOURCE_IRQ) { 655 p = string(p, pend, "irq ", str_spec); 656 specp = &dec_spec; 657 } else if (res->flags & IORESOURCE_DMA) { 658 p = string(p, pend, "dma ", str_spec); 659 specp = &dec_spec; 660 } else if (res->flags & IORESOURCE_BUS) { 661 p = string(p, pend, "bus ", str_spec); 662 specp = &bus_spec; 663 } else { 664 p = string(p, pend, "??? ", str_spec); 665 specp = &mem_spec; 666 decode = 0; 667 } 668 p = number(p, pend, res->start, *specp); 669 if (res->start != res->end) { 670 *p++ = '-'; 671 p = number(p, pend, res->end, *specp); 672 } 673 if (decode) { 674 if (res->flags & IORESOURCE_MEM_64) 675 p = string(p, pend, " 64bit", str_spec); 676 if (res->flags & IORESOURCE_PREFETCH) 677 p = string(p, pend, " pref", str_spec); 678 if (res->flags & IORESOURCE_WINDOW) 679 p = string(p, pend, " window", str_spec); 680 if (res->flags & IORESOURCE_DISABLED) 681 p = string(p, pend, " disabled", str_spec); 682 } else { 683 p = string(p, pend, " flags ", str_spec); 684 p = number(p, pend, res->flags, flag_spec); 685 } 686 *p++ = ']'; 687 *p = '\0'; 688 689 return string(buf, end, sym, spec); 690 } 691 692 static char *mac_address_string(char *buf, char *end, u8 *addr, 693 struct printf_spec spec, const char *fmt) 694 { 695 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; 696 char *p = mac_addr; 697 int i; 698 char separator; 699 700 if (fmt[1] == 'F') { /* FDDI canonical format */ 701 separator = '-'; 702 } else { 703 separator = ':'; 704 } 705 706 for (i = 0; i < 6; i++) { 707 p = pack_hex_byte(p, addr[i]); 708 if (fmt[0] == 'M' && i != 5) 709 *p++ = separator; 710 } 711 *p = '\0'; 712 713 return string(buf, end, mac_addr, spec); 714 } 715 716 static char *ip4_string(char *p, const u8 *addr, const char *fmt) 717 { 718 int i; 719 bool leading_zeros = (fmt[0] == 'i'); 720 int index; 721 int step; 722 723 switch (fmt[2]) { 724 case 'h': 725 #ifdef __BIG_ENDIAN 726 index = 0; 727 step = 1; 728 #else 729 index = 3; 730 step = -1; 731 #endif 732 break; 733 case 'l': 734 index = 3; 735 step = -1; 736 break; 737 case 'n': 738 case 'b': 739 default: 740 index = 0; 741 step = 1; 742 break; 743 } 744 for (i = 0; i < 4; i++) { 745 char temp[3]; /* hold each IP quad in reverse order */ 746 int digits = put_dec_trunc(temp, addr[index]) - temp; 747 if (leading_zeros) { 748 if (digits < 3) 749 *p++ = '0'; 750 if (digits < 2) 751 *p++ = '0'; 752 } 753 /* reverse the digits in the quad */ 754 while (digits--) 755 *p++ = temp[digits]; 756 if (i < 3) 757 *p++ = '.'; 758 index += step; 759 } 760 *p = '\0'; 761 762 return p; 763 } 764 765 static char *ip6_compressed_string(char *p, const char *addr) 766 { 767 int i, j, range; 768 unsigned char zerolength[8]; 769 int longest = 1; 770 int colonpos = -1; 771 u16 word; 772 u8 hi, lo; 773 bool needcolon = false; 774 bool useIPv4; 775 struct in6_addr in6; 776 777 memcpy(&in6, addr, sizeof(struct in6_addr)); 778 779 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6); 780 781 memset(zerolength, 0, sizeof(zerolength)); 782 783 if (useIPv4) 784 range = 6; 785 else 786 range = 8; 787 788 /* find position of longest 0 run */ 789 for (i = 0; i < range; i++) { 790 for (j = i; j < range; j++) { 791 if (in6.s6_addr16[j] != 0) 792 break; 793 zerolength[i]++; 794 } 795 } 796 for (i = 0; i < range; i++) { 797 if (zerolength[i] > longest) { 798 longest = zerolength[i]; 799 colonpos = i; 800 } 801 } 802 803 /* emit address */ 804 for (i = 0; i < range; i++) { 805 if (i == colonpos) { 806 if (needcolon || i == 0) 807 *p++ = ':'; 808 *p++ = ':'; 809 needcolon = false; 810 i += longest - 1; 811 continue; 812 } 813 if (needcolon) { 814 *p++ = ':'; 815 needcolon = false; 816 } 817 /* hex u16 without leading 0s */ 818 word = ntohs(in6.s6_addr16[i]); 819 hi = word >> 8; 820 lo = word & 0xff; 821 if (hi) { 822 if (hi > 0x0f) 823 p = pack_hex_byte(p, hi); 824 else 825 *p++ = hex_asc_lo(hi); 826 p = pack_hex_byte(p, lo); 827 } 828 else if (lo > 0x0f) 829 p = pack_hex_byte(p, lo); 830 else 831 *p++ = hex_asc_lo(lo); 832 needcolon = true; 833 } 834 835 if (useIPv4) { 836 if (needcolon) 837 *p++ = ':'; 838 p = ip4_string(p, &in6.s6_addr[12], "I4"); 839 } 840 *p = '\0'; 841 842 return p; 843 } 844 845 static char *ip6_string(char *p, const char *addr, const char *fmt) 846 { 847 int i; 848 849 for (i = 0; i < 8; i++) { 850 p = pack_hex_byte(p, *addr++); 851 p = pack_hex_byte(p, *addr++); 852 if (fmt[0] == 'I' && i != 7) 853 *p++ = ':'; 854 } 855 *p = '\0'; 856 857 return p; 858 } 859 860 static char *ip6_addr_string(char *buf, char *end, const u8 *addr, 861 struct printf_spec spec, const char *fmt) 862 { 863 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 864 865 if (fmt[0] == 'I' && fmt[2] == 'c') 866 ip6_compressed_string(ip6_addr, addr); 867 else 868 ip6_string(ip6_addr, addr, fmt); 869 870 return string(buf, end, ip6_addr, spec); 871 } 872 873 static char *ip4_addr_string(char *buf, char *end, const u8 *addr, 874 struct printf_spec spec, const char *fmt) 875 { 876 char ip4_addr[sizeof("255.255.255.255")]; 877 878 ip4_string(ip4_addr, addr, fmt); 879 880 return string(buf, end, ip4_addr, spec); 881 } 882 883 static char *uuid_string(char *buf, char *end, const u8 *addr, 884 struct printf_spec spec, const char *fmt) 885 { 886 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")]; 887 char *p = uuid; 888 int i; 889 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15}; 890 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15}; 891 const u8 *index = be; 892 bool uc = false; 893 894 switch (*(++fmt)) { 895 case 'L': 896 uc = true; /* fall-through */ 897 case 'l': 898 index = le; 899 break; 900 case 'B': 901 uc = true; 902 break; 903 } 904 905 for (i = 0; i < 16; i++) { 906 p = pack_hex_byte(p, addr[index[i]]); 907 switch (i) { 908 case 3: 909 case 5: 910 case 7: 911 case 9: 912 *p++ = '-'; 913 break; 914 } 915 } 916 917 *p = 0; 918 919 if (uc) { 920 p = uuid; 921 do { 922 *p = toupper(*p); 923 } while (*(++p)); 924 } 925 926 return string(buf, end, uuid, spec); 927 } 928 929 /* 930 * Show a '%p' thing. A kernel extension is that the '%p' is followed 931 * by an extra set of alphanumeric characters that are extended format 932 * specifiers. 933 * 934 * Right now we handle: 935 * 936 * - 'F' For symbolic function descriptor pointers with offset 937 * - 'f' For simple symbolic function names without offset 938 * - 'S' For symbolic direct pointers with offset 939 * - 's' For symbolic direct pointers without offset 940 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 941 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 942 * - 'M' For a 6-byte MAC address, it prints the address in the 943 * usual colon-separated hex notation 944 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 945 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 946 * with a dash-separated hex notation 947 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 948 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 949 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 950 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 951 * IPv6 omits the colons (01020304...0f) 952 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 953 * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order 954 * - 'I6c' for IPv6 addresses printed as specified by 955 * http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-00 956 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 957 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 958 * Options for %pU are: 959 * b big endian lower case hex (default) 960 * B big endian UPPER case hex 961 * l little endian lower case hex 962 * L little endian UPPER case hex 963 * big endian output byte order is: 964 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 965 * little endian output byte order is: 966 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 967 * 968 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64 969 * function pointers are really function descriptors, which contain a 970 * pointer to the real address. 971 */ 972 static char *pointer(const char *fmt, char *buf, char *end, void *ptr, 973 struct printf_spec spec) 974 { 975 if (!ptr) 976 return string(buf, end, "(null)", spec); 977 978 switch (*fmt) { 979 case 'F': 980 case 'f': 981 ptr = dereference_function_descriptor(ptr); 982 /* Fallthrough */ 983 case 'S': 984 case 's': 985 return symbol_string(buf, end, ptr, spec, *fmt); 986 case 'R': 987 case 'r': 988 return resource_string(buf, end, ptr, spec, fmt); 989 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 990 case 'm': /* Contiguous: 000102030405 */ 991 /* [mM]F (FDDI, bit reversed) */ 992 return mac_address_string(buf, end, ptr, spec, fmt); 993 case 'I': /* Formatted IP supported 994 * 4: 1.2.3.4 995 * 6: 0001:0203:...:0708 996 * 6c: 1::708 or 1::1.2.3.4 997 */ 998 case 'i': /* Contiguous: 999 * 4: 001.002.003.004 1000 * 6: 000102...0f 1001 */ 1002 switch (fmt[1]) { 1003 case '6': 1004 return ip6_addr_string(buf, end, ptr, spec, fmt); 1005 case '4': 1006 return ip4_addr_string(buf, end, ptr, spec, fmt); 1007 } 1008 break; 1009 case 'U': 1010 return uuid_string(buf, end, ptr, spec, fmt); 1011 } 1012 spec.flags |= SMALL; 1013 if (spec.field_width == -1) { 1014 spec.field_width = 2*sizeof(void *); 1015 spec.flags |= ZEROPAD; 1016 } 1017 spec.base = 16; 1018 1019 return number(buf, end, (unsigned long) ptr, spec); 1020 } 1021 1022 /* 1023 * Helper function to decode printf style format. 1024 * Each call decode a token from the format and return the 1025 * number of characters read (or likely the delta where it wants 1026 * to go on the next call). 1027 * The decoded token is returned through the parameters 1028 * 1029 * 'h', 'l', or 'L' for integer fields 1030 * 'z' support added 23/7/1999 S.H. 1031 * 'z' changed to 'Z' --davidm 1/25/99 1032 * 't' added for ptrdiff_t 1033 * 1034 * @fmt: the format string 1035 * @type of the token returned 1036 * @flags: various flags such as +, -, # tokens.. 1037 * @field_width: overwritten width 1038 * @base: base of the number (octal, hex, ...) 1039 * @precision: precision of a number 1040 * @qualifier: qualifier of a number (long, size_t, ...) 1041 */ 1042 static int format_decode(const char *fmt, struct printf_spec *spec) 1043 { 1044 const char *start = fmt; 1045 1046 /* we finished early by reading the field width */ 1047 if (spec->type == FORMAT_TYPE_WIDTH) { 1048 if (spec->field_width < 0) { 1049 spec->field_width = -spec->field_width; 1050 spec->flags |= LEFT; 1051 } 1052 spec->type = FORMAT_TYPE_NONE; 1053 goto precision; 1054 } 1055 1056 /* we finished early by reading the precision */ 1057 if (spec->type == FORMAT_TYPE_PRECISION) { 1058 if (spec->precision < 0) 1059 spec->precision = 0; 1060 1061 spec->type = FORMAT_TYPE_NONE; 1062 goto qualifier; 1063 } 1064 1065 /* By default */ 1066 spec->type = FORMAT_TYPE_NONE; 1067 1068 for (; *fmt ; ++fmt) { 1069 if (*fmt == '%') 1070 break; 1071 } 1072 1073 /* Return the current non-format string */ 1074 if (fmt != start || !*fmt) 1075 return fmt - start; 1076 1077 /* Process flags */ 1078 spec->flags = 0; 1079 1080 while (1) { /* this also skips first '%' */ 1081 bool found = true; 1082 1083 ++fmt; 1084 1085 switch (*fmt) { 1086 case '-': spec->flags |= LEFT; break; 1087 case '+': spec->flags |= PLUS; break; 1088 case ' ': spec->flags |= SPACE; break; 1089 case '#': spec->flags |= SPECIAL; break; 1090 case '0': spec->flags |= ZEROPAD; break; 1091 default: found = false; 1092 } 1093 1094 if (!found) 1095 break; 1096 } 1097 1098 /* get field width */ 1099 spec->field_width = -1; 1100 1101 if (isdigit(*fmt)) 1102 spec->field_width = skip_atoi(&fmt); 1103 else if (*fmt == '*') { 1104 /* it's the next argument */ 1105 spec->type = FORMAT_TYPE_WIDTH; 1106 return ++fmt - start; 1107 } 1108 1109 precision: 1110 /* get the precision */ 1111 spec->precision = -1; 1112 if (*fmt == '.') { 1113 ++fmt; 1114 if (isdigit(*fmt)) { 1115 spec->precision = skip_atoi(&fmt); 1116 if (spec->precision < 0) 1117 spec->precision = 0; 1118 } else if (*fmt == '*') { 1119 /* it's the next argument */ 1120 spec->type = FORMAT_TYPE_PRECISION; 1121 return ++fmt - start; 1122 } 1123 } 1124 1125 qualifier: 1126 /* get the conversion qualifier */ 1127 spec->qualifier = -1; 1128 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' || 1129 TOLOWER(*fmt) == 'z' || *fmt == 't') { 1130 spec->qualifier = *fmt++; 1131 if (unlikely(spec->qualifier == *fmt)) { 1132 if (spec->qualifier == 'l') { 1133 spec->qualifier = 'L'; 1134 ++fmt; 1135 } else if (spec->qualifier == 'h') { 1136 spec->qualifier = 'H'; 1137 ++fmt; 1138 } 1139 } 1140 } 1141 1142 /* default base */ 1143 spec->base = 10; 1144 switch (*fmt) { 1145 case 'c': 1146 spec->type = FORMAT_TYPE_CHAR; 1147 return ++fmt - start; 1148 1149 case 's': 1150 spec->type = FORMAT_TYPE_STR; 1151 return ++fmt - start; 1152 1153 case 'p': 1154 spec->type = FORMAT_TYPE_PTR; 1155 return fmt - start; 1156 /* skip alnum */ 1157 1158 case 'n': 1159 spec->type = FORMAT_TYPE_NRCHARS; 1160 return ++fmt - start; 1161 1162 case '%': 1163 spec->type = FORMAT_TYPE_PERCENT_CHAR; 1164 return ++fmt - start; 1165 1166 /* integer number formats - set up the flags and "break" */ 1167 case 'o': 1168 spec->base = 8; 1169 break; 1170 1171 case 'x': 1172 spec->flags |= SMALL; 1173 1174 case 'X': 1175 spec->base = 16; 1176 break; 1177 1178 case 'd': 1179 case 'i': 1180 spec->flags |= SIGN; 1181 case 'u': 1182 break; 1183 1184 default: 1185 spec->type = FORMAT_TYPE_INVALID; 1186 return fmt - start; 1187 } 1188 1189 if (spec->qualifier == 'L') 1190 spec->type = FORMAT_TYPE_LONG_LONG; 1191 else if (spec->qualifier == 'l') { 1192 if (spec->flags & SIGN) 1193 spec->type = FORMAT_TYPE_LONG; 1194 else 1195 spec->type = FORMAT_TYPE_ULONG; 1196 } else if (TOLOWER(spec->qualifier) == 'z') { 1197 spec->type = FORMAT_TYPE_SIZE_T; 1198 } else if (spec->qualifier == 't') { 1199 spec->type = FORMAT_TYPE_PTRDIFF; 1200 } else if (spec->qualifier == 'H') { 1201 if (spec->flags & SIGN) 1202 spec->type = FORMAT_TYPE_BYTE; 1203 else 1204 spec->type = FORMAT_TYPE_UBYTE; 1205 } else if (spec->qualifier == 'h') { 1206 if (spec->flags & SIGN) 1207 spec->type = FORMAT_TYPE_SHORT; 1208 else 1209 spec->type = FORMAT_TYPE_USHORT; 1210 } else { 1211 if (spec->flags & SIGN) 1212 spec->type = FORMAT_TYPE_INT; 1213 else 1214 spec->type = FORMAT_TYPE_UINT; 1215 } 1216 1217 return ++fmt - start; 1218 } 1219 1220 /** 1221 * vsnprintf - Format a string and place it in a buffer 1222 * @buf: The buffer to place the result into 1223 * @size: The size of the buffer, including the trailing null space 1224 * @fmt: The format string to use 1225 * @args: Arguments for the format string 1226 * 1227 * This function follows C99 vsnprintf, but has some extensions: 1228 * %pS output the name of a text symbol with offset 1229 * %ps output the name of a text symbol without offset 1230 * %pF output the name of a function pointer with its offset 1231 * %pf output the name of a function pointer without its offset 1232 * %pR output the address range in a struct resource with decoded flags 1233 * %pr output the address range in a struct resource with raw flags 1234 * %pM output a 6-byte MAC address with colons 1235 * %pm output a 6-byte MAC address without colons 1236 * %pI4 print an IPv4 address without leading zeros 1237 * %pi4 print an IPv4 address with leading zeros 1238 * %pI6 print an IPv6 address with colons 1239 * %pi6 print an IPv6 address without colons 1240 * %pI6c print an IPv6 address as specified by 1241 * http://tools.ietf.org/html/draft-ietf-6man-text-addr-representation-00 1242 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper 1243 * case. 1244 * %n is ignored 1245 * 1246 * The return value is the number of characters which would 1247 * be generated for the given input, excluding the trailing 1248 * '\0', as per ISO C99. If you want to have the exact 1249 * number of characters written into @buf as return value 1250 * (not including the trailing '\0'), use vscnprintf(). If the 1251 * return is greater than or equal to @size, the resulting 1252 * string is truncated. 1253 * 1254 * Call this function if you are already dealing with a va_list. 1255 * You probably want snprintf() instead. 1256 */ 1257 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) 1258 { 1259 unsigned long long num; 1260 char *str, *end; 1261 struct printf_spec spec = {0}; 1262 1263 /* Reject out-of-range values early. Large positive sizes are 1264 used for unknown buffer sizes. */ 1265 if (WARN_ON_ONCE((int) size < 0)) 1266 return 0; 1267 1268 str = buf; 1269 end = buf + size; 1270 1271 /* Make sure end is always >= buf */ 1272 if (end < buf) { 1273 end = ((void *)-1); 1274 size = end - buf; 1275 } 1276 1277 while (*fmt) { 1278 const char *old_fmt = fmt; 1279 int read = format_decode(fmt, &spec); 1280 1281 fmt += read; 1282 1283 switch (spec.type) { 1284 case FORMAT_TYPE_NONE: { 1285 int copy = read; 1286 if (str < end) { 1287 if (copy > end - str) 1288 copy = end - str; 1289 memcpy(str, old_fmt, copy); 1290 } 1291 str += read; 1292 break; 1293 } 1294 1295 case FORMAT_TYPE_WIDTH: 1296 spec.field_width = va_arg(args, int); 1297 break; 1298 1299 case FORMAT_TYPE_PRECISION: 1300 spec.precision = va_arg(args, int); 1301 break; 1302 1303 case FORMAT_TYPE_CHAR: { 1304 char c; 1305 1306 if (!(spec.flags & LEFT)) { 1307 while (--spec.field_width > 0) { 1308 if (str < end) 1309 *str = ' '; 1310 ++str; 1311 1312 } 1313 } 1314 c = (unsigned char) va_arg(args, int); 1315 if (str < end) 1316 *str = c; 1317 ++str; 1318 while (--spec.field_width > 0) { 1319 if (str < end) 1320 *str = ' '; 1321 ++str; 1322 } 1323 break; 1324 } 1325 1326 case FORMAT_TYPE_STR: 1327 str = string(str, end, va_arg(args, char *), spec); 1328 break; 1329 1330 case FORMAT_TYPE_PTR: 1331 str = pointer(fmt+1, str, end, va_arg(args, void *), 1332 spec); 1333 while (isalnum(*fmt)) 1334 fmt++; 1335 break; 1336 1337 case FORMAT_TYPE_PERCENT_CHAR: 1338 if (str < end) 1339 *str = '%'; 1340 ++str; 1341 break; 1342 1343 case FORMAT_TYPE_INVALID: 1344 if (str < end) 1345 *str = '%'; 1346 ++str; 1347 break; 1348 1349 case FORMAT_TYPE_NRCHARS: { 1350 u8 qualifier = spec.qualifier; 1351 1352 if (qualifier == 'l') { 1353 long *ip = va_arg(args, long *); 1354 *ip = (str - buf); 1355 } else if (TOLOWER(qualifier) == 'z') { 1356 size_t *ip = va_arg(args, size_t *); 1357 *ip = (str - buf); 1358 } else { 1359 int *ip = va_arg(args, int *); 1360 *ip = (str - buf); 1361 } 1362 break; 1363 } 1364 1365 default: 1366 switch (spec.type) { 1367 case FORMAT_TYPE_LONG_LONG: 1368 num = va_arg(args, long long); 1369 break; 1370 case FORMAT_TYPE_ULONG: 1371 num = va_arg(args, unsigned long); 1372 break; 1373 case FORMAT_TYPE_LONG: 1374 num = va_arg(args, long); 1375 break; 1376 case FORMAT_TYPE_SIZE_T: 1377 num = va_arg(args, size_t); 1378 break; 1379 case FORMAT_TYPE_PTRDIFF: 1380 num = va_arg(args, ptrdiff_t); 1381 break; 1382 case FORMAT_TYPE_UBYTE: 1383 num = (unsigned char) va_arg(args, int); 1384 break; 1385 case FORMAT_TYPE_BYTE: 1386 num = (signed char) va_arg(args, int); 1387 break; 1388 case FORMAT_TYPE_USHORT: 1389 num = (unsigned short) va_arg(args, int); 1390 break; 1391 case FORMAT_TYPE_SHORT: 1392 num = (short) va_arg(args, int); 1393 break; 1394 case FORMAT_TYPE_INT: 1395 num = (int) va_arg(args, int); 1396 break; 1397 default: 1398 num = va_arg(args, unsigned int); 1399 } 1400 1401 str = number(str, end, num, spec); 1402 } 1403 } 1404 1405 if (size > 0) { 1406 if (str < end) 1407 *str = '\0'; 1408 else 1409 end[-1] = '\0'; 1410 } 1411 1412 /* the trailing null byte doesn't count towards the total */ 1413 return str-buf; 1414 1415 } 1416 EXPORT_SYMBOL(vsnprintf); 1417 1418 /** 1419 * vscnprintf - Format a string and place it in a buffer 1420 * @buf: The buffer to place the result into 1421 * @size: The size of the buffer, including the trailing null space 1422 * @fmt: The format string to use 1423 * @args: Arguments for the format string 1424 * 1425 * The return value is the number of characters which have been written into 1426 * the @buf not including the trailing '\0'. If @size is <= 0 the function 1427 * returns 0. 1428 * 1429 * Call this function if you are already dealing with a va_list. 1430 * You probably want scnprintf() instead. 1431 * 1432 * See the vsnprintf() documentation for format string extensions over C99. 1433 */ 1434 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 1435 { 1436 int i; 1437 1438 i = vsnprintf(buf, size, fmt, args); 1439 1440 return (i >= size) ? (size - 1) : i; 1441 } 1442 EXPORT_SYMBOL(vscnprintf); 1443 1444 /** 1445 * snprintf - Format a string and place it in a buffer 1446 * @buf: The buffer to place the result into 1447 * @size: The size of the buffer, including the trailing null space 1448 * @fmt: The format string to use 1449 * @...: Arguments for the format string 1450 * 1451 * The return value is the number of characters which would be 1452 * generated for the given input, excluding the trailing null, 1453 * as per ISO C99. If the return is greater than or equal to 1454 * @size, the resulting string is truncated. 1455 * 1456 * See the vsnprintf() documentation for format string extensions over C99. 1457 */ 1458 int snprintf(char *buf, size_t size, const char *fmt, ...) 1459 { 1460 va_list args; 1461 int i; 1462 1463 va_start(args, fmt); 1464 i = vsnprintf(buf, size, fmt, args); 1465 va_end(args); 1466 1467 return i; 1468 } 1469 EXPORT_SYMBOL(snprintf); 1470 1471 /** 1472 * scnprintf - Format a string and place it in a buffer 1473 * @buf: The buffer to place the result into 1474 * @size: The size of the buffer, including the trailing null space 1475 * @fmt: The format string to use 1476 * @...: Arguments for the format string 1477 * 1478 * The return value is the number of characters written into @buf not including 1479 * the trailing '\0'. If @size is <= 0 the function returns 0. 1480 */ 1481 1482 int scnprintf(char *buf, size_t size, const char *fmt, ...) 1483 { 1484 va_list args; 1485 int i; 1486 1487 va_start(args, fmt); 1488 i = vsnprintf(buf, size, fmt, args); 1489 va_end(args); 1490 1491 return (i >= size) ? (size - 1) : i; 1492 } 1493 EXPORT_SYMBOL(scnprintf); 1494 1495 /** 1496 * vsprintf - Format a string and place it in a buffer 1497 * @buf: The buffer to place the result into 1498 * @fmt: The format string to use 1499 * @args: Arguments for the format string 1500 * 1501 * The function returns the number of characters written 1502 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid 1503 * buffer overflows. 1504 * 1505 * Call this function if you are already dealing with a va_list. 1506 * You probably want sprintf() instead. 1507 * 1508 * See the vsnprintf() documentation for format string extensions over C99. 1509 */ 1510 int vsprintf(char *buf, const char *fmt, va_list args) 1511 { 1512 return vsnprintf(buf, INT_MAX, fmt, args); 1513 } 1514 EXPORT_SYMBOL(vsprintf); 1515 1516 /** 1517 * sprintf - Format a string and place it in a buffer 1518 * @buf: The buffer to place the result into 1519 * @fmt: The format string to use 1520 * @...: Arguments for the format string 1521 * 1522 * The function returns the number of characters written 1523 * into @buf. Use snprintf() or scnprintf() in order to avoid 1524 * buffer overflows. 1525 * 1526 * See the vsnprintf() documentation for format string extensions over C99. 1527 */ 1528 int sprintf(char *buf, const char *fmt, ...) 1529 { 1530 va_list args; 1531 int i; 1532 1533 va_start(args, fmt); 1534 i = vsnprintf(buf, INT_MAX, fmt, args); 1535 va_end(args); 1536 1537 return i; 1538 } 1539 EXPORT_SYMBOL(sprintf); 1540 1541 #ifdef CONFIG_BINARY_PRINTF 1542 /* 1543 * bprintf service: 1544 * vbin_printf() - VA arguments to binary data 1545 * bstr_printf() - Binary data to text string 1546 */ 1547 1548 /** 1549 * vbin_printf - Parse a format string and place args' binary value in a buffer 1550 * @bin_buf: The buffer to place args' binary value 1551 * @size: The size of the buffer(by words(32bits), not characters) 1552 * @fmt: The format string to use 1553 * @args: Arguments for the format string 1554 * 1555 * The format follows C99 vsnprintf, except %n is ignored, and its argument 1556 * is skiped. 1557 * 1558 * The return value is the number of words(32bits) which would be generated for 1559 * the given input. 1560 * 1561 * NOTE: 1562 * If the return value is greater than @size, the resulting bin_buf is NOT 1563 * valid for bstr_printf(). 1564 */ 1565 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args) 1566 { 1567 struct printf_spec spec = {0}; 1568 char *str, *end; 1569 1570 str = (char *)bin_buf; 1571 end = (char *)(bin_buf + size); 1572 1573 #define save_arg(type) \ 1574 do { \ 1575 if (sizeof(type) == 8) { \ 1576 unsigned long long value; \ 1577 str = PTR_ALIGN(str, sizeof(u32)); \ 1578 value = va_arg(args, unsigned long long); \ 1579 if (str + sizeof(type) <= end) { \ 1580 *(u32 *)str = *(u32 *)&value; \ 1581 *(u32 *)(str + 4) = *((u32 *)&value + 1); \ 1582 } \ 1583 } else { \ 1584 unsigned long value; \ 1585 str = PTR_ALIGN(str, sizeof(type)); \ 1586 value = va_arg(args, int); \ 1587 if (str + sizeof(type) <= end) \ 1588 *(typeof(type) *)str = (type)value; \ 1589 } \ 1590 str += sizeof(type); \ 1591 } while (0) 1592 1593 while (*fmt) { 1594 int read = format_decode(fmt, &spec); 1595 1596 fmt += read; 1597 1598 switch (spec.type) { 1599 case FORMAT_TYPE_NONE: 1600 case FORMAT_TYPE_INVALID: 1601 case FORMAT_TYPE_PERCENT_CHAR: 1602 break; 1603 1604 case FORMAT_TYPE_WIDTH: 1605 case FORMAT_TYPE_PRECISION: 1606 save_arg(int); 1607 break; 1608 1609 case FORMAT_TYPE_CHAR: 1610 save_arg(char); 1611 break; 1612 1613 case FORMAT_TYPE_STR: { 1614 const char *save_str = va_arg(args, char *); 1615 size_t len; 1616 1617 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE 1618 || (unsigned long)save_str < PAGE_SIZE) 1619 save_str = "(null)"; 1620 len = strlen(save_str) + 1; 1621 if (str + len < end) 1622 memcpy(str, save_str, len); 1623 str += len; 1624 break; 1625 } 1626 1627 case FORMAT_TYPE_PTR: 1628 save_arg(void *); 1629 /* skip all alphanumeric pointer suffixes */ 1630 while (isalnum(*fmt)) 1631 fmt++; 1632 break; 1633 1634 case FORMAT_TYPE_NRCHARS: { 1635 /* skip %n 's argument */ 1636 u8 qualifier = spec.qualifier; 1637 void *skip_arg; 1638 if (qualifier == 'l') 1639 skip_arg = va_arg(args, long *); 1640 else if (TOLOWER(qualifier) == 'z') 1641 skip_arg = va_arg(args, size_t *); 1642 else 1643 skip_arg = va_arg(args, int *); 1644 break; 1645 } 1646 1647 default: 1648 switch (spec.type) { 1649 1650 case FORMAT_TYPE_LONG_LONG: 1651 save_arg(long long); 1652 break; 1653 case FORMAT_TYPE_ULONG: 1654 case FORMAT_TYPE_LONG: 1655 save_arg(unsigned long); 1656 break; 1657 case FORMAT_TYPE_SIZE_T: 1658 save_arg(size_t); 1659 break; 1660 case FORMAT_TYPE_PTRDIFF: 1661 save_arg(ptrdiff_t); 1662 break; 1663 case FORMAT_TYPE_UBYTE: 1664 case FORMAT_TYPE_BYTE: 1665 save_arg(char); 1666 break; 1667 case FORMAT_TYPE_USHORT: 1668 case FORMAT_TYPE_SHORT: 1669 save_arg(short); 1670 break; 1671 default: 1672 save_arg(int); 1673 } 1674 } 1675 } 1676 1677 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 1678 #undef save_arg 1679 } 1680 EXPORT_SYMBOL_GPL(vbin_printf); 1681 1682 /** 1683 * bstr_printf - Format a string from binary arguments and place it in a buffer 1684 * @buf: The buffer to place the result into 1685 * @size: The size of the buffer, including the trailing null space 1686 * @fmt: The format string to use 1687 * @bin_buf: Binary arguments for the format string 1688 * 1689 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 1690 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 1691 * a binary buffer that generated by vbin_printf. 1692 * 1693 * The format follows C99 vsnprintf, but has some extensions: 1694 * see vsnprintf comment for details. 1695 * 1696 * The return value is the number of characters which would 1697 * be generated for the given input, excluding the trailing 1698 * '\0', as per ISO C99. If you want to have the exact 1699 * number of characters written into @buf as return value 1700 * (not including the trailing '\0'), use vscnprintf(). If the 1701 * return is greater than or equal to @size, the resulting 1702 * string is truncated. 1703 */ 1704 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) 1705 { 1706 struct printf_spec spec = {0}; 1707 char *str, *end; 1708 const char *args = (const char *)bin_buf; 1709 1710 if (WARN_ON_ONCE((int) size < 0)) 1711 return 0; 1712 1713 str = buf; 1714 end = buf + size; 1715 1716 #define get_arg(type) \ 1717 ({ \ 1718 typeof(type) value; \ 1719 if (sizeof(type) == 8) { \ 1720 args = PTR_ALIGN(args, sizeof(u32)); \ 1721 *(u32 *)&value = *(u32 *)args; \ 1722 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 1723 } else { \ 1724 args = PTR_ALIGN(args, sizeof(type)); \ 1725 value = *(typeof(type) *)args; \ 1726 } \ 1727 args += sizeof(type); \ 1728 value; \ 1729 }) 1730 1731 /* Make sure end is always >= buf */ 1732 if (end < buf) { 1733 end = ((void *)-1); 1734 size = end - buf; 1735 } 1736 1737 while (*fmt) { 1738 const char *old_fmt = fmt; 1739 int read = format_decode(fmt, &spec); 1740 1741 fmt += read; 1742 1743 switch (spec.type) { 1744 case FORMAT_TYPE_NONE: { 1745 int copy = read; 1746 if (str < end) { 1747 if (copy > end - str) 1748 copy = end - str; 1749 memcpy(str, old_fmt, copy); 1750 } 1751 str += read; 1752 break; 1753 } 1754 1755 case FORMAT_TYPE_WIDTH: 1756 spec.field_width = get_arg(int); 1757 break; 1758 1759 case FORMAT_TYPE_PRECISION: 1760 spec.precision = get_arg(int); 1761 break; 1762 1763 case FORMAT_TYPE_CHAR: { 1764 char c; 1765 1766 if (!(spec.flags & LEFT)) { 1767 while (--spec.field_width > 0) { 1768 if (str < end) 1769 *str = ' '; 1770 ++str; 1771 } 1772 } 1773 c = (unsigned char) get_arg(char); 1774 if (str < end) 1775 *str = c; 1776 ++str; 1777 while (--spec.field_width > 0) { 1778 if (str < end) 1779 *str = ' '; 1780 ++str; 1781 } 1782 break; 1783 } 1784 1785 case FORMAT_TYPE_STR: { 1786 const char *str_arg = args; 1787 args += strlen(str_arg) + 1; 1788 str = string(str, end, (char *)str_arg, spec); 1789 break; 1790 } 1791 1792 case FORMAT_TYPE_PTR: 1793 str = pointer(fmt+1, str, end, get_arg(void *), spec); 1794 while (isalnum(*fmt)) 1795 fmt++; 1796 break; 1797 1798 case FORMAT_TYPE_PERCENT_CHAR: 1799 case FORMAT_TYPE_INVALID: 1800 if (str < end) 1801 *str = '%'; 1802 ++str; 1803 break; 1804 1805 case FORMAT_TYPE_NRCHARS: 1806 /* skip */ 1807 break; 1808 1809 default: { 1810 unsigned long long num; 1811 1812 switch (spec.type) { 1813 1814 case FORMAT_TYPE_LONG_LONG: 1815 num = get_arg(long long); 1816 break; 1817 case FORMAT_TYPE_ULONG: 1818 case FORMAT_TYPE_LONG: 1819 num = get_arg(unsigned long); 1820 break; 1821 case FORMAT_TYPE_SIZE_T: 1822 num = get_arg(size_t); 1823 break; 1824 case FORMAT_TYPE_PTRDIFF: 1825 num = get_arg(ptrdiff_t); 1826 break; 1827 case FORMAT_TYPE_UBYTE: 1828 num = get_arg(unsigned char); 1829 break; 1830 case FORMAT_TYPE_BYTE: 1831 num = get_arg(signed char); 1832 break; 1833 case FORMAT_TYPE_USHORT: 1834 num = get_arg(unsigned short); 1835 break; 1836 case FORMAT_TYPE_SHORT: 1837 num = get_arg(short); 1838 break; 1839 case FORMAT_TYPE_UINT: 1840 num = get_arg(unsigned int); 1841 break; 1842 default: 1843 num = get_arg(int); 1844 } 1845 1846 str = number(str, end, num, spec); 1847 } /* default: */ 1848 } /* switch(spec.type) */ 1849 } /* while(*fmt) */ 1850 1851 if (size > 0) { 1852 if (str < end) 1853 *str = '\0'; 1854 else 1855 end[-1] = '\0'; 1856 } 1857 1858 #undef get_arg 1859 1860 /* the trailing null byte doesn't count towards the total */ 1861 return str - buf; 1862 } 1863 EXPORT_SYMBOL_GPL(bstr_printf); 1864 1865 /** 1866 * bprintf - Parse a format string and place args' binary value in a buffer 1867 * @bin_buf: The buffer to place args' binary value 1868 * @size: The size of the buffer(by words(32bits), not characters) 1869 * @fmt: The format string to use 1870 * @...: Arguments for the format string 1871 * 1872 * The function returns the number of words(u32) written 1873 * into @bin_buf. 1874 */ 1875 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) 1876 { 1877 va_list args; 1878 int ret; 1879 1880 va_start(args, fmt); 1881 ret = vbin_printf(bin_buf, size, fmt, args); 1882 va_end(args); 1883 1884 return ret; 1885 } 1886 EXPORT_SYMBOL_GPL(bprintf); 1887 1888 #endif /* CONFIG_BINARY_PRINTF */ 1889 1890 /** 1891 * vsscanf - Unformat a buffer into a list of arguments 1892 * @buf: input buffer 1893 * @fmt: format of buffer 1894 * @args: arguments 1895 */ 1896 int vsscanf(const char *buf, const char *fmt, va_list args) 1897 { 1898 const char *str = buf; 1899 char *next; 1900 char digit; 1901 int num = 0; 1902 u8 qualifier; 1903 u8 base; 1904 s16 field_width; 1905 bool is_sign; 1906 1907 while (*fmt && *str) { 1908 /* skip any white space in format */ 1909 /* white space in format matchs any amount of 1910 * white space, including none, in the input. 1911 */ 1912 if (isspace(*fmt)) { 1913 fmt = skip_spaces(++fmt); 1914 str = skip_spaces(str); 1915 } 1916 1917 /* anything that is not a conversion must match exactly */ 1918 if (*fmt != '%' && *fmt) { 1919 if (*fmt++ != *str++) 1920 break; 1921 continue; 1922 } 1923 1924 if (!*fmt) 1925 break; 1926 ++fmt; 1927 1928 /* skip this conversion. 1929 * advance both strings to next white space 1930 */ 1931 if (*fmt == '*') { 1932 while (!isspace(*fmt) && *fmt != '%' && *fmt) 1933 fmt++; 1934 while (!isspace(*str) && *str) 1935 str++; 1936 continue; 1937 } 1938 1939 /* get field width */ 1940 field_width = -1; 1941 if (isdigit(*fmt)) 1942 field_width = skip_atoi(&fmt); 1943 1944 /* get conversion qualifier */ 1945 qualifier = -1; 1946 if (*fmt == 'h' || TOLOWER(*fmt) == 'l' || 1947 TOLOWER(*fmt) == 'z') { 1948 qualifier = *fmt++; 1949 if (unlikely(qualifier == *fmt)) { 1950 if (qualifier == 'h') { 1951 qualifier = 'H'; 1952 fmt++; 1953 } else if (qualifier == 'l') { 1954 qualifier = 'L'; 1955 fmt++; 1956 } 1957 } 1958 } 1959 1960 if (!*fmt || !*str) 1961 break; 1962 1963 base = 10; 1964 is_sign = 0; 1965 1966 switch (*fmt++) { 1967 case 'c': 1968 { 1969 char *s = (char *)va_arg(args, char*); 1970 if (field_width == -1) 1971 field_width = 1; 1972 do { 1973 *s++ = *str++; 1974 } while (--field_width > 0 && *str); 1975 num++; 1976 } 1977 continue; 1978 case 's': 1979 { 1980 char *s = (char *)va_arg(args, char *); 1981 if (field_width == -1) 1982 field_width = SHORT_MAX; 1983 /* first, skip leading white space in buffer */ 1984 str = skip_spaces(str); 1985 1986 /* now copy until next white space */ 1987 while (*str && !isspace(*str) && field_width--) 1988 *s++ = *str++; 1989 *s = '\0'; 1990 num++; 1991 } 1992 continue; 1993 case 'n': 1994 /* return number of characters read so far */ 1995 { 1996 int *i = (int *)va_arg(args, int*); 1997 *i = str - buf; 1998 } 1999 continue; 2000 case 'o': 2001 base = 8; 2002 break; 2003 case 'x': 2004 case 'X': 2005 base = 16; 2006 break; 2007 case 'i': 2008 base = 0; 2009 case 'd': 2010 is_sign = 1; 2011 case 'u': 2012 break; 2013 case '%': 2014 /* looking for '%' in str */ 2015 if (*str++ != '%') 2016 return num; 2017 continue; 2018 default: 2019 /* invalid format; stop here */ 2020 return num; 2021 } 2022 2023 /* have some sort of integer conversion. 2024 * first, skip white space in buffer. 2025 */ 2026 str = skip_spaces(str); 2027 2028 digit = *str; 2029 if (is_sign && digit == '-') 2030 digit = *(str + 1); 2031 2032 if (!digit 2033 || (base == 16 && !isxdigit(digit)) 2034 || (base == 10 && !isdigit(digit)) 2035 || (base == 8 && (!isdigit(digit) || digit > '7')) 2036 || (base == 0 && !isdigit(digit))) 2037 break; 2038 2039 switch (qualifier) { 2040 case 'H': /* that's 'hh' in format */ 2041 if (is_sign) { 2042 signed char *s = (signed char *)va_arg(args, signed char *); 2043 *s = (signed char)simple_strtol(str, &next, base); 2044 } else { 2045 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *); 2046 *s = (unsigned char)simple_strtoul(str, &next, base); 2047 } 2048 break; 2049 case 'h': 2050 if (is_sign) { 2051 short *s = (short *)va_arg(args, short *); 2052 *s = (short)simple_strtol(str, &next, base); 2053 } else { 2054 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *); 2055 *s = (unsigned short)simple_strtoul(str, &next, base); 2056 } 2057 break; 2058 case 'l': 2059 if (is_sign) { 2060 long *l = (long *)va_arg(args, long *); 2061 *l = simple_strtol(str, &next, base); 2062 } else { 2063 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *); 2064 *l = simple_strtoul(str, &next, base); 2065 } 2066 break; 2067 case 'L': 2068 if (is_sign) { 2069 long long *l = (long long *)va_arg(args, long long *); 2070 *l = simple_strtoll(str, &next, base); 2071 } else { 2072 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *); 2073 *l = simple_strtoull(str, &next, base); 2074 } 2075 break; 2076 case 'Z': 2077 case 'z': 2078 { 2079 size_t *s = (size_t *)va_arg(args, size_t *); 2080 *s = (size_t)simple_strtoul(str, &next, base); 2081 } 2082 break; 2083 default: 2084 if (is_sign) { 2085 int *i = (int *)va_arg(args, int *); 2086 *i = (int)simple_strtol(str, &next, base); 2087 } else { 2088 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*); 2089 *i = (unsigned int)simple_strtoul(str, &next, base); 2090 } 2091 break; 2092 } 2093 num++; 2094 2095 if (!next) 2096 break; 2097 str = next; 2098 } 2099 2100 /* 2101 * Now we've come all the way through so either the input string or the 2102 * format ended. In the former case, there can be a %n at the current 2103 * position in the format that needs to be filled. 2104 */ 2105 if (*fmt == '%' && *(fmt + 1) == 'n') { 2106 int *p = (int *)va_arg(args, int *); 2107 *p = str - buf; 2108 } 2109 2110 return num; 2111 } 2112 EXPORT_SYMBOL(vsscanf); 2113 2114 /** 2115 * sscanf - Unformat a buffer into a list of arguments 2116 * @buf: input buffer 2117 * @fmt: formatting of buffer 2118 * @...: resulting arguments 2119 */ 2120 int sscanf(const char *buf, const char *fmt, ...) 2121 { 2122 va_list args; 2123 int i; 2124 2125 va_start(args, fmt); 2126 i = vsscanf(buf, fmt, args); 2127 va_end(args); 2128 2129 return i; 2130 } 2131 EXPORT_SYMBOL(sscanf); 2132