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> /* for KSYM_SYMBOL_LEN */ 21 #include <linux/types.h> 22 #include <linux/string.h> 23 #include <linux/ctype.h> 24 #include <linux/kernel.h> 25 #include <linux/kallsyms.h> 26 #include <linux/uaccess.h> 27 #include <linux/ioport.h> 28 #include <net/addrconf.h> 29 30 #include <asm/page.h> /* for PAGE_SIZE */ 31 #include <asm/div64.h> 32 #include <asm/sections.h> /* for dereference_function_descriptor() */ 33 34 #include "kstrtox.h" 35 36 /** 37 * simple_strtoull - convert a string to an unsigned long long 38 * @cp: The start of the string 39 * @endp: A pointer to the end of the parsed string will be placed here 40 * @base: The number base to use 41 */ 42 unsigned long long simple_strtoull(const char *cp, char **endp, unsigned int base) 43 { 44 unsigned long long result; 45 unsigned int rv; 46 47 cp = _parse_integer_fixup_radix(cp, &base); 48 rv = _parse_integer(cp, base, &result); 49 /* FIXME */ 50 cp += (rv & ~KSTRTOX_OVERFLOW); 51 52 if (endp) 53 *endp = (char *)cp; 54 55 return result; 56 } 57 EXPORT_SYMBOL(simple_strtoull); 58 59 /** 60 * simple_strtoul - convert a string to an unsigned long 61 * @cp: The start of the string 62 * @endp: A pointer to the end of the parsed string will be placed here 63 * @base: The number base to use 64 */ 65 unsigned long simple_strtoul(const char *cp, char **endp, unsigned int base) 66 { 67 return simple_strtoull(cp, endp, base); 68 } 69 EXPORT_SYMBOL(simple_strtoul); 70 71 /** 72 * simple_strtol - convert a string to a signed long 73 * @cp: The start of the string 74 * @endp: A pointer to the end of the parsed string will be placed here 75 * @base: The number base to use 76 */ 77 long simple_strtol(const char *cp, char **endp, unsigned int base) 78 { 79 if (*cp == '-') 80 return -simple_strtoul(cp + 1, endp, base); 81 82 return simple_strtoul(cp, endp, base); 83 } 84 EXPORT_SYMBOL(simple_strtol); 85 86 /** 87 * simple_strtoll - convert a string to a signed long long 88 * @cp: The start of the string 89 * @endp: A pointer to the end of the parsed string will be placed here 90 * @base: The number base to use 91 */ 92 long long simple_strtoll(const char *cp, char **endp, unsigned int base) 93 { 94 if (*cp == '-') 95 return -simple_strtoull(cp + 1, endp, base); 96 97 return simple_strtoull(cp, endp, base); 98 } 99 EXPORT_SYMBOL(simple_strtoll); 100 101 static noinline_for_stack 102 int skip_atoi(const char **s) 103 { 104 int i = 0; 105 106 while (isdigit(**s)) 107 i = i*10 + *((*s)++) - '0'; 108 109 return i; 110 } 111 112 /* Decimal conversion is by far the most typical, and is used 113 * for /proc and /sys data. This directly impacts e.g. top performance 114 * with many processes running. We optimize it for speed 115 * using code from 116 * http://www.cs.uiowa.edu/~jones/bcd/decimal.html 117 * (with permission from the author, Douglas W. Jones). */ 118 119 /* Formats correctly any integer in [0,99999]. 120 * Outputs from one to five digits depending on input. 121 * On i386 gcc 4.1.2 -O2: ~250 bytes of code. */ 122 static noinline_for_stack 123 char *put_dec_trunc(char *buf, unsigned q) 124 { 125 unsigned d3, d2, d1, d0; 126 d1 = (q>>4) & 0xf; 127 d2 = (q>>8) & 0xf; 128 d3 = (q>>12); 129 130 d0 = 6*(d3 + d2 + d1) + (q & 0xf); 131 q = (d0 * 0xcd) >> 11; 132 d0 = d0 - 10*q; 133 *buf++ = d0 + '0'; /* least significant digit */ 134 d1 = q + 9*d3 + 5*d2 + d1; 135 if (d1 != 0) { 136 q = (d1 * 0xcd) >> 11; 137 d1 = d1 - 10*q; 138 *buf++ = d1 + '0'; /* next digit */ 139 140 d2 = q + 2*d2; 141 if ((d2 != 0) || (d3 != 0)) { 142 q = (d2 * 0xd) >> 7; 143 d2 = d2 - 10*q; 144 *buf++ = d2 + '0'; /* next digit */ 145 146 d3 = q + 4*d3; 147 if (d3 != 0) { 148 q = (d3 * 0xcd) >> 11; 149 d3 = d3 - 10*q; 150 *buf++ = d3 + '0'; /* next digit */ 151 if (q != 0) 152 *buf++ = q + '0'; /* most sign. digit */ 153 } 154 } 155 } 156 157 return buf; 158 } 159 /* Same with if's removed. Always emits five digits */ 160 static noinline_for_stack 161 char *put_dec_full(char *buf, unsigned q) 162 { 163 /* BTW, if q is in [0,9999], 8-bit ints will be enough, */ 164 /* but anyway, gcc produces better code with full-sized ints */ 165 unsigned d3, d2, d1, d0; 166 d1 = (q>>4) & 0xf; 167 d2 = (q>>8) & 0xf; 168 d3 = (q>>12); 169 170 /* 171 * Possible ways to approx. divide by 10 172 * gcc -O2 replaces multiply with shifts and adds 173 * (x * 0xcd) >> 11: 11001101 - shorter code than * 0x67 (on i386) 174 * (x * 0x67) >> 10: 1100111 175 * (x * 0x34) >> 9: 110100 - same 176 * (x * 0x1a) >> 8: 11010 - same 177 * (x * 0x0d) >> 7: 1101 - same, shortest code (on i386) 178 */ 179 d0 = 6*(d3 + d2 + d1) + (q & 0xf); 180 q = (d0 * 0xcd) >> 11; 181 d0 = d0 - 10*q; 182 *buf++ = d0 + '0'; 183 d1 = q + 9*d3 + 5*d2 + d1; 184 q = (d1 * 0xcd) >> 11; 185 d1 = d1 - 10*q; 186 *buf++ = d1 + '0'; 187 188 d2 = q + 2*d2; 189 q = (d2 * 0xd) >> 7; 190 d2 = d2 - 10*q; 191 *buf++ = d2 + '0'; 192 193 d3 = q + 4*d3; 194 q = (d3 * 0xcd) >> 11; /* - shorter code */ 195 /* q = (d3 * 0x67) >> 10; - would also work */ 196 d3 = d3 - 10*q; 197 *buf++ = d3 + '0'; 198 *buf++ = q + '0'; 199 200 return buf; 201 } 202 /* No inlining helps gcc to use registers better */ 203 static noinline_for_stack 204 char *put_dec(char *buf, unsigned long long num) 205 { 206 while (1) { 207 unsigned rem; 208 if (num < 100000) 209 return put_dec_trunc(buf, num); 210 rem = do_div(num, 100000); 211 buf = put_dec_full(buf, rem); 212 } 213 } 214 215 /* 216 * Convert passed number to decimal string. 217 * Returns the length of string. On buffer overflow, returns 0. 218 * 219 * If speed is not important, use snprintf(). It's easy to read the code. 220 */ 221 int num_to_str(char *buf, int size, unsigned long long num) 222 { 223 char tmp[21]; /* Enough for 2^64 in decimal */ 224 int idx, len; 225 226 len = put_dec(tmp, num) - tmp; 227 228 if (len > size) 229 return 0; 230 for (idx = 0; idx < len; ++idx) 231 buf[idx] = tmp[len - idx - 1]; 232 return len; 233 } 234 235 #define ZEROPAD 1 /* pad with zero */ 236 #define SIGN 2 /* unsigned/signed long */ 237 #define PLUS 4 /* show plus */ 238 #define SPACE 8 /* space if plus */ 239 #define LEFT 16 /* left justified */ 240 #define SMALL 32 /* use lowercase in hex (must be 32 == 0x20) */ 241 #define SPECIAL 64 /* prefix hex with "0x", octal with "0" */ 242 243 enum format_type { 244 FORMAT_TYPE_NONE, /* Just a string part */ 245 FORMAT_TYPE_WIDTH, 246 FORMAT_TYPE_PRECISION, 247 FORMAT_TYPE_CHAR, 248 FORMAT_TYPE_STR, 249 FORMAT_TYPE_PTR, 250 FORMAT_TYPE_PERCENT_CHAR, 251 FORMAT_TYPE_INVALID, 252 FORMAT_TYPE_LONG_LONG, 253 FORMAT_TYPE_ULONG, 254 FORMAT_TYPE_LONG, 255 FORMAT_TYPE_UBYTE, 256 FORMAT_TYPE_BYTE, 257 FORMAT_TYPE_USHORT, 258 FORMAT_TYPE_SHORT, 259 FORMAT_TYPE_UINT, 260 FORMAT_TYPE_INT, 261 FORMAT_TYPE_NRCHARS, 262 FORMAT_TYPE_SIZE_T, 263 FORMAT_TYPE_PTRDIFF 264 }; 265 266 struct printf_spec { 267 u8 type; /* format_type enum */ 268 u8 flags; /* flags to number() */ 269 u8 base; /* number base, 8, 10 or 16 only */ 270 u8 qualifier; /* number qualifier, one of 'hHlLtzZ' */ 271 s16 field_width; /* width of output field */ 272 s16 precision; /* # of digits/chars */ 273 }; 274 275 static noinline_for_stack 276 char *number(char *buf, char *end, unsigned long long num, 277 struct printf_spec spec) 278 { 279 /* we are called with base 8, 10 or 16, only, thus don't need "G..." */ 280 static const char digits[16] = "0123456789ABCDEF"; /* "GHIJKLMNOPQRSTUVWXYZ"; */ 281 282 char tmp[66]; 283 char sign; 284 char locase; 285 int need_pfx = ((spec.flags & SPECIAL) && spec.base != 10); 286 int i; 287 288 /* locase = 0 or 0x20. ORing digits or letters with 'locase' 289 * produces same digits or (maybe lowercased) letters */ 290 locase = (spec.flags & SMALL); 291 if (spec.flags & LEFT) 292 spec.flags &= ~ZEROPAD; 293 sign = 0; 294 if (spec.flags & SIGN) { 295 if ((signed long long)num < 0) { 296 sign = '-'; 297 num = -(signed long long)num; 298 spec.field_width--; 299 } else if (spec.flags & PLUS) { 300 sign = '+'; 301 spec.field_width--; 302 } else if (spec.flags & SPACE) { 303 sign = ' '; 304 spec.field_width--; 305 } 306 } 307 if (need_pfx) { 308 spec.field_width--; 309 if (spec.base == 16) 310 spec.field_width--; 311 } 312 313 /* generate full string in tmp[], in reverse order */ 314 i = 0; 315 if (num == 0) 316 tmp[i++] = '0'; 317 /* Generic code, for any base: 318 else do { 319 tmp[i++] = (digits[do_div(num,base)] | locase); 320 } while (num != 0); 321 */ 322 else if (spec.base != 10) { /* 8 or 16 */ 323 int mask = spec.base - 1; 324 int shift = 3; 325 326 if (spec.base == 16) 327 shift = 4; 328 do { 329 tmp[i++] = (digits[((unsigned char)num) & mask] | locase); 330 num >>= shift; 331 } while (num); 332 } else { /* base 10 */ 333 i = put_dec(tmp, num) - tmp; 334 } 335 336 /* printing 100 using %2d gives "100", not "00" */ 337 if (i > spec.precision) 338 spec.precision = i; 339 /* leading space padding */ 340 spec.field_width -= spec.precision; 341 if (!(spec.flags & (ZEROPAD+LEFT))) { 342 while (--spec.field_width >= 0) { 343 if (buf < end) 344 *buf = ' '; 345 ++buf; 346 } 347 } 348 /* sign */ 349 if (sign) { 350 if (buf < end) 351 *buf = sign; 352 ++buf; 353 } 354 /* "0x" / "0" prefix */ 355 if (need_pfx) { 356 if (buf < end) 357 *buf = '0'; 358 ++buf; 359 if (spec.base == 16) { 360 if (buf < end) 361 *buf = ('X' | locase); 362 ++buf; 363 } 364 } 365 /* zero or space padding */ 366 if (!(spec.flags & LEFT)) { 367 char c = (spec.flags & ZEROPAD) ? '0' : ' '; 368 while (--spec.field_width >= 0) { 369 if (buf < end) 370 *buf = c; 371 ++buf; 372 } 373 } 374 /* hmm even more zero padding? */ 375 while (i <= --spec.precision) { 376 if (buf < end) 377 *buf = '0'; 378 ++buf; 379 } 380 /* actual digits of result */ 381 while (--i >= 0) { 382 if (buf < end) 383 *buf = tmp[i]; 384 ++buf; 385 } 386 /* trailing space padding */ 387 while (--spec.field_width >= 0) { 388 if (buf < end) 389 *buf = ' '; 390 ++buf; 391 } 392 393 return buf; 394 } 395 396 static noinline_for_stack 397 char *string(char *buf, char *end, const char *s, struct printf_spec spec) 398 { 399 int len, i; 400 401 if ((unsigned long)s < PAGE_SIZE) 402 s = "(null)"; 403 404 len = strnlen(s, spec.precision); 405 406 if (!(spec.flags & LEFT)) { 407 while (len < spec.field_width--) { 408 if (buf < end) 409 *buf = ' '; 410 ++buf; 411 } 412 } 413 for (i = 0; i < len; ++i) { 414 if (buf < end) 415 *buf = *s; 416 ++buf; ++s; 417 } 418 while (len < spec.field_width--) { 419 if (buf < end) 420 *buf = ' '; 421 ++buf; 422 } 423 424 return buf; 425 } 426 427 static noinline_for_stack 428 char *symbol_string(char *buf, char *end, void *ptr, 429 struct printf_spec spec, char ext) 430 { 431 unsigned long value = (unsigned long) ptr; 432 #ifdef CONFIG_KALLSYMS 433 char sym[KSYM_SYMBOL_LEN]; 434 if (ext == 'B') 435 sprint_backtrace(sym, value); 436 else if (ext != 'f' && ext != 's') 437 sprint_symbol(sym, value); 438 else 439 kallsyms_lookup(value, NULL, NULL, NULL, sym); 440 441 return string(buf, end, sym, spec); 442 #else 443 spec.field_width = 2 * sizeof(void *); 444 spec.flags |= SPECIAL | SMALL | ZEROPAD; 445 spec.base = 16; 446 447 return number(buf, end, value, spec); 448 #endif 449 } 450 451 static noinline_for_stack 452 char *resource_string(char *buf, char *end, struct resource *res, 453 struct printf_spec spec, const char *fmt) 454 { 455 #ifndef IO_RSRC_PRINTK_SIZE 456 #define IO_RSRC_PRINTK_SIZE 6 457 #endif 458 459 #ifndef MEM_RSRC_PRINTK_SIZE 460 #define MEM_RSRC_PRINTK_SIZE 10 461 #endif 462 static const struct printf_spec io_spec = { 463 .base = 16, 464 .field_width = IO_RSRC_PRINTK_SIZE, 465 .precision = -1, 466 .flags = SPECIAL | SMALL | ZEROPAD, 467 }; 468 static const struct printf_spec mem_spec = { 469 .base = 16, 470 .field_width = MEM_RSRC_PRINTK_SIZE, 471 .precision = -1, 472 .flags = SPECIAL | SMALL | ZEROPAD, 473 }; 474 static const struct printf_spec bus_spec = { 475 .base = 16, 476 .field_width = 2, 477 .precision = -1, 478 .flags = SMALL | ZEROPAD, 479 }; 480 static const struct printf_spec dec_spec = { 481 .base = 10, 482 .precision = -1, 483 .flags = 0, 484 }; 485 static const struct printf_spec str_spec = { 486 .field_width = -1, 487 .precision = 10, 488 .flags = LEFT, 489 }; 490 static const struct printf_spec flag_spec = { 491 .base = 16, 492 .precision = -1, 493 .flags = SPECIAL | SMALL, 494 }; 495 496 /* 32-bit res (sizeof==4): 10 chars in dec, 10 in hex ("0x" + 8) 497 * 64-bit res (sizeof==8): 20 chars in dec, 18 in hex ("0x" + 16) */ 498 #define RSRC_BUF_SIZE ((2 * sizeof(resource_size_t)) + 4) 499 #define FLAG_BUF_SIZE (2 * sizeof(res->flags)) 500 #define DECODED_BUF_SIZE sizeof("[mem - 64bit pref window disabled]") 501 #define RAW_BUF_SIZE sizeof("[mem - flags 0x]") 502 char sym[max(2*RSRC_BUF_SIZE + DECODED_BUF_SIZE, 503 2*RSRC_BUF_SIZE + FLAG_BUF_SIZE + RAW_BUF_SIZE)]; 504 505 char *p = sym, *pend = sym + sizeof(sym); 506 int decode = (fmt[0] == 'R') ? 1 : 0; 507 const struct printf_spec *specp; 508 509 *p++ = '['; 510 if (res->flags & IORESOURCE_IO) { 511 p = string(p, pend, "io ", str_spec); 512 specp = &io_spec; 513 } else if (res->flags & IORESOURCE_MEM) { 514 p = string(p, pend, "mem ", str_spec); 515 specp = &mem_spec; 516 } else if (res->flags & IORESOURCE_IRQ) { 517 p = string(p, pend, "irq ", str_spec); 518 specp = &dec_spec; 519 } else if (res->flags & IORESOURCE_DMA) { 520 p = string(p, pend, "dma ", str_spec); 521 specp = &dec_spec; 522 } else if (res->flags & IORESOURCE_BUS) { 523 p = string(p, pend, "bus ", str_spec); 524 specp = &bus_spec; 525 } else { 526 p = string(p, pend, "??? ", str_spec); 527 specp = &mem_spec; 528 decode = 0; 529 } 530 p = number(p, pend, res->start, *specp); 531 if (res->start != res->end) { 532 *p++ = '-'; 533 p = number(p, pend, res->end, *specp); 534 } 535 if (decode) { 536 if (res->flags & IORESOURCE_MEM_64) 537 p = string(p, pend, " 64bit", str_spec); 538 if (res->flags & IORESOURCE_PREFETCH) 539 p = string(p, pend, " pref", str_spec); 540 if (res->flags & IORESOURCE_WINDOW) 541 p = string(p, pend, " window", str_spec); 542 if (res->flags & IORESOURCE_DISABLED) 543 p = string(p, pend, " disabled", str_spec); 544 } else { 545 p = string(p, pend, " flags ", str_spec); 546 p = number(p, pend, res->flags, flag_spec); 547 } 548 *p++ = ']'; 549 *p = '\0'; 550 551 return string(buf, end, sym, spec); 552 } 553 554 static noinline_for_stack 555 char *mac_address_string(char *buf, char *end, u8 *addr, 556 struct printf_spec spec, const char *fmt) 557 { 558 char mac_addr[sizeof("xx:xx:xx:xx:xx:xx")]; 559 char *p = mac_addr; 560 int i; 561 char separator; 562 563 if (fmt[1] == 'F') { /* FDDI canonical format */ 564 separator = '-'; 565 } else { 566 separator = ':'; 567 } 568 569 for (i = 0; i < 6; i++) { 570 p = hex_byte_pack(p, addr[i]); 571 if (fmt[0] == 'M' && i != 5) 572 *p++ = separator; 573 } 574 *p = '\0'; 575 576 return string(buf, end, mac_addr, spec); 577 } 578 579 static noinline_for_stack 580 char *ip4_string(char *p, const u8 *addr, const char *fmt) 581 { 582 int i; 583 bool leading_zeros = (fmt[0] == 'i'); 584 int index; 585 int step; 586 587 switch (fmt[2]) { 588 case 'h': 589 #ifdef __BIG_ENDIAN 590 index = 0; 591 step = 1; 592 #else 593 index = 3; 594 step = -1; 595 #endif 596 break; 597 case 'l': 598 index = 3; 599 step = -1; 600 break; 601 case 'n': 602 case 'b': 603 default: 604 index = 0; 605 step = 1; 606 break; 607 } 608 for (i = 0; i < 4; i++) { 609 char temp[3]; /* hold each IP quad in reverse order */ 610 int digits = put_dec_trunc(temp, addr[index]) - temp; 611 if (leading_zeros) { 612 if (digits < 3) 613 *p++ = '0'; 614 if (digits < 2) 615 *p++ = '0'; 616 } 617 /* reverse the digits in the quad */ 618 while (digits--) 619 *p++ = temp[digits]; 620 if (i < 3) 621 *p++ = '.'; 622 index += step; 623 } 624 *p = '\0'; 625 626 return p; 627 } 628 629 static noinline_for_stack 630 char *ip6_compressed_string(char *p, const char *addr) 631 { 632 int i, j, range; 633 unsigned char zerolength[8]; 634 int longest = 1; 635 int colonpos = -1; 636 u16 word; 637 u8 hi, lo; 638 bool needcolon = false; 639 bool useIPv4; 640 struct in6_addr in6; 641 642 memcpy(&in6, addr, sizeof(struct in6_addr)); 643 644 useIPv4 = ipv6_addr_v4mapped(&in6) || ipv6_addr_is_isatap(&in6); 645 646 memset(zerolength, 0, sizeof(zerolength)); 647 648 if (useIPv4) 649 range = 6; 650 else 651 range = 8; 652 653 /* find position of longest 0 run */ 654 for (i = 0; i < range; i++) { 655 for (j = i; j < range; j++) { 656 if (in6.s6_addr16[j] != 0) 657 break; 658 zerolength[i]++; 659 } 660 } 661 for (i = 0; i < range; i++) { 662 if (zerolength[i] > longest) { 663 longest = zerolength[i]; 664 colonpos = i; 665 } 666 } 667 if (longest == 1) /* don't compress a single 0 */ 668 colonpos = -1; 669 670 /* emit address */ 671 for (i = 0; i < range; i++) { 672 if (i == colonpos) { 673 if (needcolon || i == 0) 674 *p++ = ':'; 675 *p++ = ':'; 676 needcolon = false; 677 i += longest - 1; 678 continue; 679 } 680 if (needcolon) { 681 *p++ = ':'; 682 needcolon = false; 683 } 684 /* hex u16 without leading 0s */ 685 word = ntohs(in6.s6_addr16[i]); 686 hi = word >> 8; 687 lo = word & 0xff; 688 if (hi) { 689 if (hi > 0x0f) 690 p = hex_byte_pack(p, hi); 691 else 692 *p++ = hex_asc_lo(hi); 693 p = hex_byte_pack(p, lo); 694 } 695 else if (lo > 0x0f) 696 p = hex_byte_pack(p, lo); 697 else 698 *p++ = hex_asc_lo(lo); 699 needcolon = true; 700 } 701 702 if (useIPv4) { 703 if (needcolon) 704 *p++ = ':'; 705 p = ip4_string(p, &in6.s6_addr[12], "I4"); 706 } 707 *p = '\0'; 708 709 return p; 710 } 711 712 static noinline_for_stack 713 char *ip6_string(char *p, const char *addr, const char *fmt) 714 { 715 int i; 716 717 for (i = 0; i < 8; i++) { 718 p = hex_byte_pack(p, *addr++); 719 p = hex_byte_pack(p, *addr++); 720 if (fmt[0] == 'I' && i != 7) 721 *p++ = ':'; 722 } 723 *p = '\0'; 724 725 return p; 726 } 727 728 static noinline_for_stack 729 char *ip6_addr_string(char *buf, char *end, const u8 *addr, 730 struct printf_spec spec, const char *fmt) 731 { 732 char ip6_addr[sizeof("xxxx:xxxx:xxxx:xxxx:xxxx:xxxx:255.255.255.255")]; 733 734 if (fmt[0] == 'I' && fmt[2] == 'c') 735 ip6_compressed_string(ip6_addr, addr); 736 else 737 ip6_string(ip6_addr, addr, fmt); 738 739 return string(buf, end, ip6_addr, spec); 740 } 741 742 static noinline_for_stack 743 char *ip4_addr_string(char *buf, char *end, const u8 *addr, 744 struct printf_spec spec, const char *fmt) 745 { 746 char ip4_addr[sizeof("255.255.255.255")]; 747 748 ip4_string(ip4_addr, addr, fmt); 749 750 return string(buf, end, ip4_addr, spec); 751 } 752 753 static noinline_for_stack 754 char *uuid_string(char *buf, char *end, const u8 *addr, 755 struct printf_spec spec, const char *fmt) 756 { 757 char uuid[sizeof("xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx")]; 758 char *p = uuid; 759 int i; 760 static const u8 be[16] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15}; 761 static const u8 le[16] = {3,2,1,0,5,4,7,6,8,9,10,11,12,13,14,15}; 762 const u8 *index = be; 763 bool uc = false; 764 765 switch (*(++fmt)) { 766 case 'L': 767 uc = true; /* fall-through */ 768 case 'l': 769 index = le; 770 break; 771 case 'B': 772 uc = true; 773 break; 774 } 775 776 for (i = 0; i < 16; i++) { 777 p = hex_byte_pack(p, addr[index[i]]); 778 switch (i) { 779 case 3: 780 case 5: 781 case 7: 782 case 9: 783 *p++ = '-'; 784 break; 785 } 786 } 787 788 *p = 0; 789 790 if (uc) { 791 p = uuid; 792 do { 793 *p = toupper(*p); 794 } while (*(++p)); 795 } 796 797 return string(buf, end, uuid, spec); 798 } 799 800 static 801 char *netdev_feature_string(char *buf, char *end, const u8 *addr, 802 struct printf_spec spec) 803 { 804 spec.flags |= SPECIAL | SMALL | ZEROPAD; 805 if (spec.field_width == -1) 806 spec.field_width = 2 + 2 * sizeof(netdev_features_t); 807 spec.base = 16; 808 809 return number(buf, end, *(const netdev_features_t *)addr, spec); 810 } 811 812 int kptr_restrict __read_mostly; 813 814 /* 815 * Show a '%p' thing. A kernel extension is that the '%p' is followed 816 * by an extra set of alphanumeric characters that are extended format 817 * specifiers. 818 * 819 * Right now we handle: 820 * 821 * - 'F' For symbolic function descriptor pointers with offset 822 * - 'f' For simple symbolic function names without offset 823 * - 'S' For symbolic direct pointers with offset 824 * - 's' For symbolic direct pointers without offset 825 * - 'B' For backtraced symbolic direct pointers with offset 826 * - 'R' For decoded struct resource, e.g., [mem 0x0-0x1f 64bit pref] 827 * - 'r' For raw struct resource, e.g., [mem 0x0-0x1f flags 0x201] 828 * - 'M' For a 6-byte MAC address, it prints the address in the 829 * usual colon-separated hex notation 830 * - 'm' For a 6-byte MAC address, it prints the hex address without colons 831 * - 'MF' For a 6-byte MAC FDDI address, it prints the address 832 * with a dash-separated hex notation 833 * - 'I' [46] for IPv4/IPv6 addresses printed in the usual way 834 * IPv4 uses dot-separated decimal without leading 0's (1.2.3.4) 835 * IPv6 uses colon separated network-order 16 bit hex with leading 0's 836 * - 'i' [46] for 'raw' IPv4/IPv6 addresses 837 * IPv6 omits the colons (01020304...0f) 838 * IPv4 uses dot-separated decimal with leading 0's (010.123.045.006) 839 * - '[Ii]4[hnbl]' IPv4 addresses in host, network, big or little endian order 840 * - 'I6c' for IPv6 addresses printed as specified by 841 * http://tools.ietf.org/html/rfc5952 842 * - 'U' For a 16 byte UUID/GUID, it prints the UUID/GUID in the form 843 * "xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx" 844 * Options for %pU are: 845 * b big endian lower case hex (default) 846 * B big endian UPPER case hex 847 * l little endian lower case hex 848 * L little endian UPPER case hex 849 * big endian output byte order is: 850 * [0][1][2][3]-[4][5]-[6][7]-[8][9]-[10][11][12][13][14][15] 851 * little endian output byte order is: 852 * [3][2][1][0]-[5][4]-[7][6]-[8][9]-[10][11][12][13][14][15] 853 * - 'V' For a struct va_format which contains a format string * and va_list *, 854 * call vsnprintf(->format, *->va_list). 855 * Implements a "recursive vsnprintf". 856 * Do not use this feature without some mechanism to verify the 857 * correctness of the format string and va_list arguments. 858 * - 'K' For a kernel pointer that should be hidden from unprivileged users 859 * - 'NF' For a netdev_features_t 860 * 861 * Note: The difference between 'S' and 'F' is that on ia64 and ppc64 862 * function pointers are really function descriptors, which contain a 863 * pointer to the real address. 864 */ 865 static noinline_for_stack 866 char *pointer(const char *fmt, char *buf, char *end, void *ptr, 867 struct printf_spec spec) 868 { 869 if (!ptr && *fmt != 'K') { 870 /* 871 * Print (null) with the same width as a pointer so it makes 872 * tabular output look nice. 873 */ 874 if (spec.field_width == -1) 875 spec.field_width = 2 * sizeof(void *); 876 return string(buf, end, "(null)", spec); 877 } 878 879 switch (*fmt) { 880 case 'F': 881 case 'f': 882 ptr = dereference_function_descriptor(ptr); 883 /* Fallthrough */ 884 case 'S': 885 case 's': 886 case 'B': 887 return symbol_string(buf, end, ptr, spec, *fmt); 888 case 'R': 889 case 'r': 890 return resource_string(buf, end, ptr, spec, fmt); 891 case 'M': /* Colon separated: 00:01:02:03:04:05 */ 892 case 'm': /* Contiguous: 000102030405 */ 893 /* [mM]F (FDDI, bit reversed) */ 894 return mac_address_string(buf, end, ptr, spec, fmt); 895 case 'I': /* Formatted IP supported 896 * 4: 1.2.3.4 897 * 6: 0001:0203:...:0708 898 * 6c: 1::708 or 1::1.2.3.4 899 */ 900 case 'i': /* Contiguous: 901 * 4: 001.002.003.004 902 * 6: 000102...0f 903 */ 904 switch (fmt[1]) { 905 case '6': 906 return ip6_addr_string(buf, end, ptr, spec, fmt); 907 case '4': 908 return ip4_addr_string(buf, end, ptr, spec, fmt); 909 } 910 break; 911 case 'U': 912 return uuid_string(buf, end, ptr, spec, fmt); 913 case 'V': 914 { 915 va_list va; 916 917 va_copy(va, *((struct va_format *)ptr)->va); 918 buf += vsnprintf(buf, end > buf ? end - buf : 0, 919 ((struct va_format *)ptr)->fmt, va); 920 va_end(va); 921 return buf; 922 } 923 case 'K': 924 /* 925 * %pK cannot be used in IRQ context because its test 926 * for CAP_SYSLOG would be meaningless. 927 */ 928 if (in_irq() || in_serving_softirq() || in_nmi()) { 929 if (spec.field_width == -1) 930 spec.field_width = 2 * sizeof(void *); 931 return string(buf, end, "pK-error", spec); 932 } 933 if (!((kptr_restrict == 0) || 934 (kptr_restrict == 1 && 935 has_capability_noaudit(current, CAP_SYSLOG)))) 936 ptr = NULL; 937 break; 938 case 'N': 939 switch (fmt[1]) { 940 case 'F': 941 return netdev_feature_string(buf, end, ptr, spec); 942 } 943 break; 944 } 945 spec.flags |= SMALL; 946 if (spec.field_width == -1) { 947 spec.field_width = 2 * sizeof(void *); 948 spec.flags |= ZEROPAD; 949 } 950 spec.base = 16; 951 952 return number(buf, end, (unsigned long) ptr, spec); 953 } 954 955 /* 956 * Helper function to decode printf style format. 957 * Each call decode a token from the format and return the 958 * number of characters read (or likely the delta where it wants 959 * to go on the next call). 960 * The decoded token is returned through the parameters 961 * 962 * 'h', 'l', or 'L' for integer fields 963 * 'z' support added 23/7/1999 S.H. 964 * 'z' changed to 'Z' --davidm 1/25/99 965 * 't' added for ptrdiff_t 966 * 967 * @fmt: the format string 968 * @type of the token returned 969 * @flags: various flags such as +, -, # tokens.. 970 * @field_width: overwritten width 971 * @base: base of the number (octal, hex, ...) 972 * @precision: precision of a number 973 * @qualifier: qualifier of a number (long, size_t, ...) 974 */ 975 static noinline_for_stack 976 int format_decode(const char *fmt, struct printf_spec *spec) 977 { 978 const char *start = fmt; 979 980 /* we finished early by reading the field width */ 981 if (spec->type == FORMAT_TYPE_WIDTH) { 982 if (spec->field_width < 0) { 983 spec->field_width = -spec->field_width; 984 spec->flags |= LEFT; 985 } 986 spec->type = FORMAT_TYPE_NONE; 987 goto precision; 988 } 989 990 /* we finished early by reading the precision */ 991 if (spec->type == FORMAT_TYPE_PRECISION) { 992 if (spec->precision < 0) 993 spec->precision = 0; 994 995 spec->type = FORMAT_TYPE_NONE; 996 goto qualifier; 997 } 998 999 /* By default */ 1000 spec->type = FORMAT_TYPE_NONE; 1001 1002 for (; *fmt ; ++fmt) { 1003 if (*fmt == '%') 1004 break; 1005 } 1006 1007 /* Return the current non-format string */ 1008 if (fmt != start || !*fmt) 1009 return fmt - start; 1010 1011 /* Process flags */ 1012 spec->flags = 0; 1013 1014 while (1) { /* this also skips first '%' */ 1015 bool found = true; 1016 1017 ++fmt; 1018 1019 switch (*fmt) { 1020 case '-': spec->flags |= LEFT; break; 1021 case '+': spec->flags |= PLUS; break; 1022 case ' ': spec->flags |= SPACE; break; 1023 case '#': spec->flags |= SPECIAL; break; 1024 case '0': spec->flags |= ZEROPAD; break; 1025 default: found = false; 1026 } 1027 1028 if (!found) 1029 break; 1030 } 1031 1032 /* get field width */ 1033 spec->field_width = -1; 1034 1035 if (isdigit(*fmt)) 1036 spec->field_width = skip_atoi(&fmt); 1037 else if (*fmt == '*') { 1038 /* it's the next argument */ 1039 spec->type = FORMAT_TYPE_WIDTH; 1040 return ++fmt - start; 1041 } 1042 1043 precision: 1044 /* get the precision */ 1045 spec->precision = -1; 1046 if (*fmt == '.') { 1047 ++fmt; 1048 if (isdigit(*fmt)) { 1049 spec->precision = skip_atoi(&fmt); 1050 if (spec->precision < 0) 1051 spec->precision = 0; 1052 } else if (*fmt == '*') { 1053 /* it's the next argument */ 1054 spec->type = FORMAT_TYPE_PRECISION; 1055 return ++fmt - start; 1056 } 1057 } 1058 1059 qualifier: 1060 /* get the conversion qualifier */ 1061 spec->qualifier = -1; 1062 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 1063 _tolower(*fmt) == 'z' || *fmt == 't') { 1064 spec->qualifier = *fmt++; 1065 if (unlikely(spec->qualifier == *fmt)) { 1066 if (spec->qualifier == 'l') { 1067 spec->qualifier = 'L'; 1068 ++fmt; 1069 } else if (spec->qualifier == 'h') { 1070 spec->qualifier = 'H'; 1071 ++fmt; 1072 } 1073 } 1074 } 1075 1076 /* default base */ 1077 spec->base = 10; 1078 switch (*fmt) { 1079 case 'c': 1080 spec->type = FORMAT_TYPE_CHAR; 1081 return ++fmt - start; 1082 1083 case 's': 1084 spec->type = FORMAT_TYPE_STR; 1085 return ++fmt - start; 1086 1087 case 'p': 1088 spec->type = FORMAT_TYPE_PTR; 1089 return fmt - start; 1090 /* skip alnum */ 1091 1092 case 'n': 1093 spec->type = FORMAT_TYPE_NRCHARS; 1094 return ++fmt - start; 1095 1096 case '%': 1097 spec->type = FORMAT_TYPE_PERCENT_CHAR; 1098 return ++fmt - start; 1099 1100 /* integer number formats - set up the flags and "break" */ 1101 case 'o': 1102 spec->base = 8; 1103 break; 1104 1105 case 'x': 1106 spec->flags |= SMALL; 1107 1108 case 'X': 1109 spec->base = 16; 1110 break; 1111 1112 case 'd': 1113 case 'i': 1114 spec->flags |= SIGN; 1115 case 'u': 1116 break; 1117 1118 default: 1119 spec->type = FORMAT_TYPE_INVALID; 1120 return fmt - start; 1121 } 1122 1123 if (spec->qualifier == 'L') 1124 spec->type = FORMAT_TYPE_LONG_LONG; 1125 else if (spec->qualifier == 'l') { 1126 if (spec->flags & SIGN) 1127 spec->type = FORMAT_TYPE_LONG; 1128 else 1129 spec->type = FORMAT_TYPE_ULONG; 1130 } else if (_tolower(spec->qualifier) == 'z') { 1131 spec->type = FORMAT_TYPE_SIZE_T; 1132 } else if (spec->qualifier == 't') { 1133 spec->type = FORMAT_TYPE_PTRDIFF; 1134 } else if (spec->qualifier == 'H') { 1135 if (spec->flags & SIGN) 1136 spec->type = FORMAT_TYPE_BYTE; 1137 else 1138 spec->type = FORMAT_TYPE_UBYTE; 1139 } else if (spec->qualifier == 'h') { 1140 if (spec->flags & SIGN) 1141 spec->type = FORMAT_TYPE_SHORT; 1142 else 1143 spec->type = FORMAT_TYPE_USHORT; 1144 } else { 1145 if (spec->flags & SIGN) 1146 spec->type = FORMAT_TYPE_INT; 1147 else 1148 spec->type = FORMAT_TYPE_UINT; 1149 } 1150 1151 return ++fmt - start; 1152 } 1153 1154 /** 1155 * vsnprintf - Format a string and place it in a buffer 1156 * @buf: The buffer to place the result into 1157 * @size: The size of the buffer, including the trailing null space 1158 * @fmt: The format string to use 1159 * @args: Arguments for the format string 1160 * 1161 * This function follows C99 vsnprintf, but has some extensions: 1162 * %pS output the name of a text symbol with offset 1163 * %ps output the name of a text symbol without offset 1164 * %pF output the name of a function pointer with its offset 1165 * %pf output the name of a function pointer without its offset 1166 * %pB output the name of a backtrace symbol with its offset 1167 * %pR output the address range in a struct resource with decoded flags 1168 * %pr output the address range in a struct resource with raw flags 1169 * %pM output a 6-byte MAC address with colons 1170 * %pm output a 6-byte MAC address without colons 1171 * %pI4 print an IPv4 address without leading zeros 1172 * %pi4 print an IPv4 address with leading zeros 1173 * %pI6 print an IPv6 address with colons 1174 * %pi6 print an IPv6 address without colons 1175 * %pI6c print an IPv6 address as specified by RFC 5952 1176 * %pU[bBlL] print a UUID/GUID in big or little endian using lower or upper 1177 * case. 1178 * %n is ignored 1179 * 1180 * The return value is the number of characters which would 1181 * be generated for the given input, excluding the trailing 1182 * '\0', as per ISO C99. If you want to have the exact 1183 * number of characters written into @buf as return value 1184 * (not including the trailing '\0'), use vscnprintf(). If the 1185 * return is greater than or equal to @size, the resulting 1186 * string is truncated. 1187 * 1188 * If you're not already dealing with a va_list consider using snprintf(). 1189 */ 1190 int vsnprintf(char *buf, size_t size, const char *fmt, va_list args) 1191 { 1192 unsigned long long num; 1193 char *str, *end; 1194 struct printf_spec spec = {0}; 1195 1196 /* Reject out-of-range values early. Large positive sizes are 1197 used for unknown buffer sizes. */ 1198 if (WARN_ON_ONCE((int) size < 0)) 1199 return 0; 1200 1201 str = buf; 1202 end = buf + size; 1203 1204 /* Make sure end is always >= buf */ 1205 if (end < buf) { 1206 end = ((void *)-1); 1207 size = end - buf; 1208 } 1209 1210 while (*fmt) { 1211 const char *old_fmt = fmt; 1212 int read = format_decode(fmt, &spec); 1213 1214 fmt += read; 1215 1216 switch (spec.type) { 1217 case FORMAT_TYPE_NONE: { 1218 int copy = read; 1219 if (str < end) { 1220 if (copy > end - str) 1221 copy = end - str; 1222 memcpy(str, old_fmt, copy); 1223 } 1224 str += read; 1225 break; 1226 } 1227 1228 case FORMAT_TYPE_WIDTH: 1229 spec.field_width = va_arg(args, int); 1230 break; 1231 1232 case FORMAT_TYPE_PRECISION: 1233 spec.precision = va_arg(args, int); 1234 break; 1235 1236 case FORMAT_TYPE_CHAR: { 1237 char c; 1238 1239 if (!(spec.flags & LEFT)) { 1240 while (--spec.field_width > 0) { 1241 if (str < end) 1242 *str = ' '; 1243 ++str; 1244 1245 } 1246 } 1247 c = (unsigned char) va_arg(args, int); 1248 if (str < end) 1249 *str = c; 1250 ++str; 1251 while (--spec.field_width > 0) { 1252 if (str < end) 1253 *str = ' '; 1254 ++str; 1255 } 1256 break; 1257 } 1258 1259 case FORMAT_TYPE_STR: 1260 str = string(str, end, va_arg(args, char *), spec); 1261 break; 1262 1263 case FORMAT_TYPE_PTR: 1264 str = pointer(fmt+1, str, end, va_arg(args, void *), 1265 spec); 1266 while (isalnum(*fmt)) 1267 fmt++; 1268 break; 1269 1270 case FORMAT_TYPE_PERCENT_CHAR: 1271 if (str < end) 1272 *str = '%'; 1273 ++str; 1274 break; 1275 1276 case FORMAT_TYPE_INVALID: 1277 if (str < end) 1278 *str = '%'; 1279 ++str; 1280 break; 1281 1282 case FORMAT_TYPE_NRCHARS: { 1283 u8 qualifier = spec.qualifier; 1284 1285 if (qualifier == 'l') { 1286 long *ip = va_arg(args, long *); 1287 *ip = (str - buf); 1288 } else if (_tolower(qualifier) == 'z') { 1289 size_t *ip = va_arg(args, size_t *); 1290 *ip = (str - buf); 1291 } else { 1292 int *ip = va_arg(args, int *); 1293 *ip = (str - buf); 1294 } 1295 break; 1296 } 1297 1298 default: 1299 switch (spec.type) { 1300 case FORMAT_TYPE_LONG_LONG: 1301 num = va_arg(args, long long); 1302 break; 1303 case FORMAT_TYPE_ULONG: 1304 num = va_arg(args, unsigned long); 1305 break; 1306 case FORMAT_TYPE_LONG: 1307 num = va_arg(args, long); 1308 break; 1309 case FORMAT_TYPE_SIZE_T: 1310 num = va_arg(args, size_t); 1311 break; 1312 case FORMAT_TYPE_PTRDIFF: 1313 num = va_arg(args, ptrdiff_t); 1314 break; 1315 case FORMAT_TYPE_UBYTE: 1316 num = (unsigned char) va_arg(args, int); 1317 break; 1318 case FORMAT_TYPE_BYTE: 1319 num = (signed char) va_arg(args, int); 1320 break; 1321 case FORMAT_TYPE_USHORT: 1322 num = (unsigned short) va_arg(args, int); 1323 break; 1324 case FORMAT_TYPE_SHORT: 1325 num = (short) va_arg(args, int); 1326 break; 1327 case FORMAT_TYPE_INT: 1328 num = (int) va_arg(args, int); 1329 break; 1330 default: 1331 num = va_arg(args, unsigned int); 1332 } 1333 1334 str = number(str, end, num, spec); 1335 } 1336 } 1337 1338 if (size > 0) { 1339 if (str < end) 1340 *str = '\0'; 1341 else 1342 end[-1] = '\0'; 1343 } 1344 1345 /* the trailing null byte doesn't count towards the total */ 1346 return str-buf; 1347 1348 } 1349 EXPORT_SYMBOL(vsnprintf); 1350 1351 /** 1352 * vscnprintf - Format a string and place it in a buffer 1353 * @buf: The buffer to place the result into 1354 * @size: The size of the buffer, including the trailing null space 1355 * @fmt: The format string to use 1356 * @args: Arguments for the format string 1357 * 1358 * The return value is the number of characters which have been written into 1359 * the @buf not including the trailing '\0'. If @size is == 0 the function 1360 * returns 0. 1361 * 1362 * If you're not already dealing with a va_list consider using scnprintf(). 1363 * 1364 * See the vsnprintf() documentation for format string extensions over C99. 1365 */ 1366 int vscnprintf(char *buf, size_t size, const char *fmt, va_list args) 1367 { 1368 int i; 1369 1370 i = vsnprintf(buf, size, fmt, args); 1371 1372 if (likely(i < size)) 1373 return i; 1374 if (size != 0) 1375 return size - 1; 1376 return 0; 1377 } 1378 EXPORT_SYMBOL(vscnprintf); 1379 1380 /** 1381 * snprintf - Format a string and place it in a buffer 1382 * @buf: The buffer to place the result into 1383 * @size: The size of the buffer, including the trailing null space 1384 * @fmt: The format string to use 1385 * @...: Arguments for the format string 1386 * 1387 * The return value is the number of characters which would be 1388 * generated for the given input, excluding the trailing null, 1389 * as per ISO C99. If the return is greater than or equal to 1390 * @size, the resulting string is truncated. 1391 * 1392 * See the vsnprintf() documentation for format string extensions over C99. 1393 */ 1394 int snprintf(char *buf, size_t size, const char *fmt, ...) 1395 { 1396 va_list args; 1397 int i; 1398 1399 va_start(args, fmt); 1400 i = vsnprintf(buf, size, fmt, args); 1401 va_end(args); 1402 1403 return i; 1404 } 1405 EXPORT_SYMBOL(snprintf); 1406 1407 /** 1408 * scnprintf - Format a string and place it in a buffer 1409 * @buf: The buffer to place the result into 1410 * @size: The size of the buffer, including the trailing null space 1411 * @fmt: The format string to use 1412 * @...: Arguments for the format string 1413 * 1414 * The return value is the number of characters written into @buf not including 1415 * the trailing '\0'. If @size is == 0 the function returns 0. 1416 */ 1417 1418 int scnprintf(char *buf, size_t size, const char *fmt, ...) 1419 { 1420 va_list args; 1421 int i; 1422 1423 va_start(args, fmt); 1424 i = vscnprintf(buf, size, fmt, args); 1425 va_end(args); 1426 1427 return i; 1428 } 1429 EXPORT_SYMBOL(scnprintf); 1430 1431 /** 1432 * vsprintf - Format a string and place it in a buffer 1433 * @buf: The buffer to place the result into 1434 * @fmt: The format string to use 1435 * @args: Arguments for the format string 1436 * 1437 * The function returns the number of characters written 1438 * into @buf. Use vsnprintf() or vscnprintf() in order to avoid 1439 * buffer overflows. 1440 * 1441 * If you're not already dealing with a va_list consider using sprintf(). 1442 * 1443 * See the vsnprintf() documentation for format string extensions over C99. 1444 */ 1445 int vsprintf(char *buf, const char *fmt, va_list args) 1446 { 1447 return vsnprintf(buf, INT_MAX, fmt, args); 1448 } 1449 EXPORT_SYMBOL(vsprintf); 1450 1451 /** 1452 * sprintf - Format a string and place it in a buffer 1453 * @buf: The buffer to place the result into 1454 * @fmt: The format string to use 1455 * @...: Arguments for the format string 1456 * 1457 * The function returns the number of characters written 1458 * into @buf. Use snprintf() or scnprintf() in order to avoid 1459 * buffer overflows. 1460 * 1461 * See the vsnprintf() documentation for format string extensions over C99. 1462 */ 1463 int sprintf(char *buf, const char *fmt, ...) 1464 { 1465 va_list args; 1466 int i; 1467 1468 va_start(args, fmt); 1469 i = vsnprintf(buf, INT_MAX, fmt, args); 1470 va_end(args); 1471 1472 return i; 1473 } 1474 EXPORT_SYMBOL(sprintf); 1475 1476 #ifdef CONFIG_BINARY_PRINTF 1477 /* 1478 * bprintf service: 1479 * vbin_printf() - VA arguments to binary data 1480 * bstr_printf() - Binary data to text string 1481 */ 1482 1483 /** 1484 * vbin_printf - Parse a format string and place args' binary value in a buffer 1485 * @bin_buf: The buffer to place args' binary value 1486 * @size: The size of the buffer(by words(32bits), not characters) 1487 * @fmt: The format string to use 1488 * @args: Arguments for the format string 1489 * 1490 * The format follows C99 vsnprintf, except %n is ignored, and its argument 1491 * is skiped. 1492 * 1493 * The return value is the number of words(32bits) which would be generated for 1494 * the given input. 1495 * 1496 * NOTE: 1497 * If the return value is greater than @size, the resulting bin_buf is NOT 1498 * valid for bstr_printf(). 1499 */ 1500 int vbin_printf(u32 *bin_buf, size_t size, const char *fmt, va_list args) 1501 { 1502 struct printf_spec spec = {0}; 1503 char *str, *end; 1504 1505 str = (char *)bin_buf; 1506 end = (char *)(bin_buf + size); 1507 1508 #define save_arg(type) \ 1509 do { \ 1510 if (sizeof(type) == 8) { \ 1511 unsigned long long value; \ 1512 str = PTR_ALIGN(str, sizeof(u32)); \ 1513 value = va_arg(args, unsigned long long); \ 1514 if (str + sizeof(type) <= end) { \ 1515 *(u32 *)str = *(u32 *)&value; \ 1516 *(u32 *)(str + 4) = *((u32 *)&value + 1); \ 1517 } \ 1518 } else { \ 1519 unsigned long value; \ 1520 str = PTR_ALIGN(str, sizeof(type)); \ 1521 value = va_arg(args, int); \ 1522 if (str + sizeof(type) <= end) \ 1523 *(typeof(type) *)str = (type)value; \ 1524 } \ 1525 str += sizeof(type); \ 1526 } while (0) 1527 1528 while (*fmt) { 1529 int read = format_decode(fmt, &spec); 1530 1531 fmt += read; 1532 1533 switch (spec.type) { 1534 case FORMAT_TYPE_NONE: 1535 case FORMAT_TYPE_INVALID: 1536 case FORMAT_TYPE_PERCENT_CHAR: 1537 break; 1538 1539 case FORMAT_TYPE_WIDTH: 1540 case FORMAT_TYPE_PRECISION: 1541 save_arg(int); 1542 break; 1543 1544 case FORMAT_TYPE_CHAR: 1545 save_arg(char); 1546 break; 1547 1548 case FORMAT_TYPE_STR: { 1549 const char *save_str = va_arg(args, char *); 1550 size_t len; 1551 1552 if ((unsigned long)save_str > (unsigned long)-PAGE_SIZE 1553 || (unsigned long)save_str < PAGE_SIZE) 1554 save_str = "(null)"; 1555 len = strlen(save_str) + 1; 1556 if (str + len < end) 1557 memcpy(str, save_str, len); 1558 str += len; 1559 break; 1560 } 1561 1562 case FORMAT_TYPE_PTR: 1563 save_arg(void *); 1564 /* skip all alphanumeric pointer suffixes */ 1565 while (isalnum(*fmt)) 1566 fmt++; 1567 break; 1568 1569 case FORMAT_TYPE_NRCHARS: { 1570 /* skip %n 's argument */ 1571 u8 qualifier = spec.qualifier; 1572 void *skip_arg; 1573 if (qualifier == 'l') 1574 skip_arg = va_arg(args, long *); 1575 else if (_tolower(qualifier) == 'z') 1576 skip_arg = va_arg(args, size_t *); 1577 else 1578 skip_arg = va_arg(args, int *); 1579 break; 1580 } 1581 1582 default: 1583 switch (spec.type) { 1584 1585 case FORMAT_TYPE_LONG_LONG: 1586 save_arg(long long); 1587 break; 1588 case FORMAT_TYPE_ULONG: 1589 case FORMAT_TYPE_LONG: 1590 save_arg(unsigned long); 1591 break; 1592 case FORMAT_TYPE_SIZE_T: 1593 save_arg(size_t); 1594 break; 1595 case FORMAT_TYPE_PTRDIFF: 1596 save_arg(ptrdiff_t); 1597 break; 1598 case FORMAT_TYPE_UBYTE: 1599 case FORMAT_TYPE_BYTE: 1600 save_arg(char); 1601 break; 1602 case FORMAT_TYPE_USHORT: 1603 case FORMAT_TYPE_SHORT: 1604 save_arg(short); 1605 break; 1606 default: 1607 save_arg(int); 1608 } 1609 } 1610 } 1611 1612 return (u32 *)(PTR_ALIGN(str, sizeof(u32))) - bin_buf; 1613 #undef save_arg 1614 } 1615 EXPORT_SYMBOL_GPL(vbin_printf); 1616 1617 /** 1618 * bstr_printf - Format a string from binary arguments and place it in a buffer 1619 * @buf: The buffer to place the result into 1620 * @size: The size of the buffer, including the trailing null space 1621 * @fmt: The format string to use 1622 * @bin_buf: Binary arguments for the format string 1623 * 1624 * This function like C99 vsnprintf, but the difference is that vsnprintf gets 1625 * arguments from stack, and bstr_printf gets arguments from @bin_buf which is 1626 * a binary buffer that generated by vbin_printf. 1627 * 1628 * The format follows C99 vsnprintf, but has some extensions: 1629 * see vsnprintf comment for details. 1630 * 1631 * The return value is the number of characters which would 1632 * be generated for the given input, excluding the trailing 1633 * '\0', as per ISO C99. If you want to have the exact 1634 * number of characters written into @buf as return value 1635 * (not including the trailing '\0'), use vscnprintf(). If the 1636 * return is greater than or equal to @size, the resulting 1637 * string is truncated. 1638 */ 1639 int bstr_printf(char *buf, size_t size, const char *fmt, const u32 *bin_buf) 1640 { 1641 struct printf_spec spec = {0}; 1642 char *str, *end; 1643 const char *args = (const char *)bin_buf; 1644 1645 if (WARN_ON_ONCE((int) size < 0)) 1646 return 0; 1647 1648 str = buf; 1649 end = buf + size; 1650 1651 #define get_arg(type) \ 1652 ({ \ 1653 typeof(type) value; \ 1654 if (sizeof(type) == 8) { \ 1655 args = PTR_ALIGN(args, sizeof(u32)); \ 1656 *(u32 *)&value = *(u32 *)args; \ 1657 *((u32 *)&value + 1) = *(u32 *)(args + 4); \ 1658 } else { \ 1659 args = PTR_ALIGN(args, sizeof(type)); \ 1660 value = *(typeof(type) *)args; \ 1661 } \ 1662 args += sizeof(type); \ 1663 value; \ 1664 }) 1665 1666 /* Make sure end is always >= buf */ 1667 if (end < buf) { 1668 end = ((void *)-1); 1669 size = end - buf; 1670 } 1671 1672 while (*fmt) { 1673 const char *old_fmt = fmt; 1674 int read = format_decode(fmt, &spec); 1675 1676 fmt += read; 1677 1678 switch (spec.type) { 1679 case FORMAT_TYPE_NONE: { 1680 int copy = read; 1681 if (str < end) { 1682 if (copy > end - str) 1683 copy = end - str; 1684 memcpy(str, old_fmt, copy); 1685 } 1686 str += read; 1687 break; 1688 } 1689 1690 case FORMAT_TYPE_WIDTH: 1691 spec.field_width = get_arg(int); 1692 break; 1693 1694 case FORMAT_TYPE_PRECISION: 1695 spec.precision = get_arg(int); 1696 break; 1697 1698 case FORMAT_TYPE_CHAR: { 1699 char c; 1700 1701 if (!(spec.flags & LEFT)) { 1702 while (--spec.field_width > 0) { 1703 if (str < end) 1704 *str = ' '; 1705 ++str; 1706 } 1707 } 1708 c = (unsigned char) get_arg(char); 1709 if (str < end) 1710 *str = c; 1711 ++str; 1712 while (--spec.field_width > 0) { 1713 if (str < end) 1714 *str = ' '; 1715 ++str; 1716 } 1717 break; 1718 } 1719 1720 case FORMAT_TYPE_STR: { 1721 const char *str_arg = args; 1722 args += strlen(str_arg) + 1; 1723 str = string(str, end, (char *)str_arg, spec); 1724 break; 1725 } 1726 1727 case FORMAT_TYPE_PTR: 1728 str = pointer(fmt+1, str, end, get_arg(void *), spec); 1729 while (isalnum(*fmt)) 1730 fmt++; 1731 break; 1732 1733 case FORMAT_TYPE_PERCENT_CHAR: 1734 case FORMAT_TYPE_INVALID: 1735 if (str < end) 1736 *str = '%'; 1737 ++str; 1738 break; 1739 1740 case FORMAT_TYPE_NRCHARS: 1741 /* skip */ 1742 break; 1743 1744 default: { 1745 unsigned long long num; 1746 1747 switch (spec.type) { 1748 1749 case FORMAT_TYPE_LONG_LONG: 1750 num = get_arg(long long); 1751 break; 1752 case FORMAT_TYPE_ULONG: 1753 case FORMAT_TYPE_LONG: 1754 num = get_arg(unsigned long); 1755 break; 1756 case FORMAT_TYPE_SIZE_T: 1757 num = get_arg(size_t); 1758 break; 1759 case FORMAT_TYPE_PTRDIFF: 1760 num = get_arg(ptrdiff_t); 1761 break; 1762 case FORMAT_TYPE_UBYTE: 1763 num = get_arg(unsigned char); 1764 break; 1765 case FORMAT_TYPE_BYTE: 1766 num = get_arg(signed char); 1767 break; 1768 case FORMAT_TYPE_USHORT: 1769 num = get_arg(unsigned short); 1770 break; 1771 case FORMAT_TYPE_SHORT: 1772 num = get_arg(short); 1773 break; 1774 case FORMAT_TYPE_UINT: 1775 num = get_arg(unsigned int); 1776 break; 1777 default: 1778 num = get_arg(int); 1779 } 1780 1781 str = number(str, end, num, spec); 1782 } /* default: */ 1783 } /* switch(spec.type) */ 1784 } /* while(*fmt) */ 1785 1786 if (size > 0) { 1787 if (str < end) 1788 *str = '\0'; 1789 else 1790 end[-1] = '\0'; 1791 } 1792 1793 #undef get_arg 1794 1795 /* the trailing null byte doesn't count towards the total */ 1796 return str - buf; 1797 } 1798 EXPORT_SYMBOL_GPL(bstr_printf); 1799 1800 /** 1801 * bprintf - Parse a format string and place args' binary value in a buffer 1802 * @bin_buf: The buffer to place args' binary value 1803 * @size: The size of the buffer(by words(32bits), not characters) 1804 * @fmt: The format string to use 1805 * @...: Arguments for the format string 1806 * 1807 * The function returns the number of words(u32) written 1808 * into @bin_buf. 1809 */ 1810 int bprintf(u32 *bin_buf, size_t size, const char *fmt, ...) 1811 { 1812 va_list args; 1813 int ret; 1814 1815 va_start(args, fmt); 1816 ret = vbin_printf(bin_buf, size, fmt, args); 1817 va_end(args); 1818 1819 return ret; 1820 } 1821 EXPORT_SYMBOL_GPL(bprintf); 1822 1823 #endif /* CONFIG_BINARY_PRINTF */ 1824 1825 /** 1826 * vsscanf - Unformat a buffer into a list of arguments 1827 * @buf: input buffer 1828 * @fmt: format of buffer 1829 * @args: arguments 1830 */ 1831 int vsscanf(const char *buf, const char *fmt, va_list args) 1832 { 1833 const char *str = buf; 1834 char *next; 1835 char digit; 1836 int num = 0; 1837 u8 qualifier; 1838 u8 base; 1839 s16 field_width; 1840 bool is_sign; 1841 1842 while (*fmt && *str) { 1843 /* skip any white space in format */ 1844 /* white space in format matchs any amount of 1845 * white space, including none, in the input. 1846 */ 1847 if (isspace(*fmt)) { 1848 fmt = skip_spaces(++fmt); 1849 str = skip_spaces(str); 1850 } 1851 1852 /* anything that is not a conversion must match exactly */ 1853 if (*fmt != '%' && *fmt) { 1854 if (*fmt++ != *str++) 1855 break; 1856 continue; 1857 } 1858 1859 if (!*fmt) 1860 break; 1861 ++fmt; 1862 1863 /* skip this conversion. 1864 * advance both strings to next white space 1865 */ 1866 if (*fmt == '*') { 1867 while (!isspace(*fmt) && *fmt != '%' && *fmt) 1868 fmt++; 1869 while (!isspace(*str) && *str) 1870 str++; 1871 continue; 1872 } 1873 1874 /* get field width */ 1875 field_width = -1; 1876 if (isdigit(*fmt)) 1877 field_width = skip_atoi(&fmt); 1878 1879 /* get conversion qualifier */ 1880 qualifier = -1; 1881 if (*fmt == 'h' || _tolower(*fmt) == 'l' || 1882 _tolower(*fmt) == 'z') { 1883 qualifier = *fmt++; 1884 if (unlikely(qualifier == *fmt)) { 1885 if (qualifier == 'h') { 1886 qualifier = 'H'; 1887 fmt++; 1888 } else if (qualifier == 'l') { 1889 qualifier = 'L'; 1890 fmt++; 1891 } 1892 } 1893 } 1894 1895 if (!*fmt || !*str) 1896 break; 1897 1898 base = 10; 1899 is_sign = 0; 1900 1901 switch (*fmt++) { 1902 case 'c': 1903 { 1904 char *s = (char *)va_arg(args, char*); 1905 if (field_width == -1) 1906 field_width = 1; 1907 do { 1908 *s++ = *str++; 1909 } while (--field_width > 0 && *str); 1910 num++; 1911 } 1912 continue; 1913 case 's': 1914 { 1915 char *s = (char *)va_arg(args, char *); 1916 if (field_width == -1) 1917 field_width = SHRT_MAX; 1918 /* first, skip leading white space in buffer */ 1919 str = skip_spaces(str); 1920 1921 /* now copy until next white space */ 1922 while (*str && !isspace(*str) && field_width--) 1923 *s++ = *str++; 1924 *s = '\0'; 1925 num++; 1926 } 1927 continue; 1928 case 'n': 1929 /* return number of characters read so far */ 1930 { 1931 int *i = (int *)va_arg(args, int*); 1932 *i = str - buf; 1933 } 1934 continue; 1935 case 'o': 1936 base = 8; 1937 break; 1938 case 'x': 1939 case 'X': 1940 base = 16; 1941 break; 1942 case 'i': 1943 base = 0; 1944 case 'd': 1945 is_sign = 1; 1946 case 'u': 1947 break; 1948 case '%': 1949 /* looking for '%' in str */ 1950 if (*str++ != '%') 1951 return num; 1952 continue; 1953 default: 1954 /* invalid format; stop here */ 1955 return num; 1956 } 1957 1958 /* have some sort of integer conversion. 1959 * first, skip white space in buffer. 1960 */ 1961 str = skip_spaces(str); 1962 1963 digit = *str; 1964 if (is_sign && digit == '-') 1965 digit = *(str + 1); 1966 1967 if (!digit 1968 || (base == 16 && !isxdigit(digit)) 1969 || (base == 10 && !isdigit(digit)) 1970 || (base == 8 && (!isdigit(digit) || digit > '7')) 1971 || (base == 0 && !isdigit(digit))) 1972 break; 1973 1974 switch (qualifier) { 1975 case 'H': /* that's 'hh' in format */ 1976 if (is_sign) { 1977 signed char *s = (signed char *)va_arg(args, signed char *); 1978 *s = (signed char)simple_strtol(str, &next, base); 1979 } else { 1980 unsigned char *s = (unsigned char *)va_arg(args, unsigned char *); 1981 *s = (unsigned char)simple_strtoul(str, &next, base); 1982 } 1983 break; 1984 case 'h': 1985 if (is_sign) { 1986 short *s = (short *)va_arg(args, short *); 1987 *s = (short)simple_strtol(str, &next, base); 1988 } else { 1989 unsigned short *s = (unsigned short *)va_arg(args, unsigned short *); 1990 *s = (unsigned short)simple_strtoul(str, &next, base); 1991 } 1992 break; 1993 case 'l': 1994 if (is_sign) { 1995 long *l = (long *)va_arg(args, long *); 1996 *l = simple_strtol(str, &next, base); 1997 } else { 1998 unsigned long *l = (unsigned long *)va_arg(args, unsigned long *); 1999 *l = simple_strtoul(str, &next, base); 2000 } 2001 break; 2002 case 'L': 2003 if (is_sign) { 2004 long long *l = (long long *)va_arg(args, long long *); 2005 *l = simple_strtoll(str, &next, base); 2006 } else { 2007 unsigned long long *l = (unsigned long long *)va_arg(args, unsigned long long *); 2008 *l = simple_strtoull(str, &next, base); 2009 } 2010 break; 2011 case 'Z': 2012 case 'z': 2013 { 2014 size_t *s = (size_t *)va_arg(args, size_t *); 2015 *s = (size_t)simple_strtoul(str, &next, base); 2016 } 2017 break; 2018 default: 2019 if (is_sign) { 2020 int *i = (int *)va_arg(args, int *); 2021 *i = (int)simple_strtol(str, &next, base); 2022 } else { 2023 unsigned int *i = (unsigned int *)va_arg(args, unsigned int*); 2024 *i = (unsigned int)simple_strtoul(str, &next, base); 2025 } 2026 break; 2027 } 2028 num++; 2029 2030 if (!next) 2031 break; 2032 str = next; 2033 } 2034 2035 /* 2036 * Now we've come all the way through so either the input string or the 2037 * format ended. In the former case, there can be a %n at the current 2038 * position in the format that needs to be filled. 2039 */ 2040 if (*fmt == '%' && *(fmt + 1) == 'n') { 2041 int *p = (int *)va_arg(args, int *); 2042 *p = str - buf; 2043 } 2044 2045 return num; 2046 } 2047 EXPORT_SYMBOL(vsscanf); 2048 2049 /** 2050 * sscanf - Unformat a buffer into a list of arguments 2051 * @buf: input buffer 2052 * @fmt: formatting of buffer 2053 * @...: resulting arguments 2054 */ 2055 int sscanf(const char *buf, const char *fmt, ...) 2056 { 2057 va_list args; 2058 int i; 2059 2060 va_start(args, fmt); 2061 i = vsscanf(buf, fmt, args); 2062 va_end(args); 2063 2064 return i; 2065 } 2066 EXPORT_SYMBOL(sscanf); 2067