util/cutils.c

   1 /*
   2  * Simple C functions to supplement the C library
   3  *
   4  * Copyright (c) 2006 Fabrice Bellard
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24 #include "qemu/osdep.h"
  25 #include "qemu-common.h"
  26 #include "qemu/host-utils.h"
  27 #include <math.h>
  28
  29 #include "qemu/sockets.h"
  30 #include "qemu/iov.h"
  31 #include "net/net.h"
  32 #include "qemu/cutils.h"
  33
  34 void strpadcpy(char *buf, int buf_size, const char *str, char pad)
  35 {
  36     int len = qemu_strnlen(str, buf_size);
  37     memcpy(buf, str, len);
  38     memset(buf + len, pad, buf_size - len);
  39 }
  40
  41 void pstrcpy(char *buf, int buf_size, const char *str)
  42 {
  43     int c;
  44     char *q = buf;
  45
  46     if (buf_size <= 0)
  47         return;
  48
  49     for(;;) {
  50         c = *str++;
  51         if (c == 0 || q >= buf + buf_size - 1)
  52             break;
  53         *q++ = c;
  54     }
  55     *q = '\0';
  56 }
  57
  58 /* strcat and truncate. */
  59 char *pstrcat(char *buf, int buf_size, const char *s)
  60 {
  61     int len;
  62     len = strlen(buf);
  63     if (len < buf_size)
  64         pstrcpy(buf + len, buf_size - len, s);
  65     return buf;
  66 }
  67
  68 int strstart(const char *str, const char *val, const char **ptr)
  69 {
  70     const char *p, *q;
  71     p = str;
  72     q = val;
  73     while (*q != '\0') {
  74         if (*p != *q)
  75             return 0;
  76         p++;
  77         q++;
  78     }
  79     if (ptr)
  80         *ptr = p;
  81     return 1;
  82 }
  83
  84 int stristart(const char *str, const char *val, const char **ptr)
  85 {
  86     const char *p, *q;
  87     p = str;
  88     q = val;
  89     while (*q != '\0') {
  90         if (qemu_toupper(*p) != qemu_toupper(*q))
  91             return 0;
  92         p++;
  93         q++;
  94     }
  95     if (ptr)
  96         *ptr = p;
  97     return 1;
  98 }
  99
 100 /* XXX: use host strnlen if available ? */
 101 int qemu_strnlen(const char *s, int max_len)
 102 {
 103     int i;
 104
 105     for(i = 0; i < max_len; i++) {
 106         if (s[i] == '\0') {
 107             break;
 108         }
 109     }
 110     return i;
 111 }
 112
 113 char *qemu_strsep(char **input, const char *delim)
 114 {
 115     char *result = *input;
 116     if (result != NULL) {
 117         char *p;
 118
 119         for (p = result; *p != '\0'; p++) {
 120             if (strchr(delim, *p)) {
 121                 break;
 122             }
 123         }
 124         if (*p == '\0') {
 125             *input = NULL;
 126         } else {
 127             *p = '\0';
 128             *input = p + 1;
 129         }
 130     }
 131     return result;
 132 }
 133
 134 time_t mktimegm(struct tm *tm)
 135 {
 136     time_t t;
 137     int y = tm->tm_year + 1900, m = tm->tm_mon + 1, d = tm->tm_mday;
 138     if (m < 3) {
 139         m += 12;
 140         y--;
 141     }
 142     t = 86400ULL * (d + (153 * m - 457) / 5 + 365 * y + y / 4 - y / 100 +
 143                  y / 400 - 719469);
 144     t += 3600 * tm->tm_hour + 60 * tm->tm_min + tm->tm_sec;
 145     return t;
 146 }
 147
 148 /*
 149  * Make sure data goes on disk, but if possible do not bother to
 150  * write out the inode just for timestamp updates.
 151  *
 152  * Unfortunately even in 2009 many operating systems do not support
 153  * fdatasync and have to fall back to fsync.
 154  */
 155 int qemu_fdatasync(int fd)
 156 {
 157 #ifdef CONFIG_FDATASYNC
 158     return fdatasync(fd);
 159 #elif defined(_WIN64)
 160     /* TODO: Implement fsync for w64, too. */
 161     return NOERROR;
 162 #else
 163     return fsync(fd);
 164 #endif
 165 }
 166
 167 #ifndef _WIN32
 168 /* Sets a specific flag */
 169 int fcntl_setfl(int fd, int flag)
 170 {
 171     int flags;
 172
 173     flags = fcntl(fd, F_GETFL);
 174     if (flags == -1)
 175         return -errno;
 176
 177     if (fcntl(fd, F_SETFL, flags | flag) == -1)
 178         return -errno;
 179
 180     return 0;
 181 }
 182 #endif
 183
 184 static int64_t suffix_mul(char suffix, int64_t unit)
 185 {
 186     switch (qemu_toupper(suffix)) {
 187     case QEMU_STRTOSZ_DEFSUFFIX_B:
 188         return 1;
 189     case QEMU_STRTOSZ_DEFSUFFIX_KB:
 190         return unit;
 191     case QEMU_STRTOSZ_DEFSUFFIX_MB:
 192         return unit * unit;
 193     case QEMU_STRTOSZ_DEFSUFFIX_GB:
 194         return unit * unit * unit;
 195     case QEMU_STRTOSZ_DEFSUFFIX_TB:
 196         return unit * unit * unit * unit;
 197     case QEMU_STRTOSZ_DEFSUFFIX_PB:
 198         return unit * unit * unit * unit * unit;
 199     case QEMU_STRTOSZ_DEFSUFFIX_EB:
 200         return unit * unit * unit * unit * unit * unit;
 201     }
 202     return -1;
 203 }
 204
 205 /*
 206  * Convert string to bytes, allowing either B/b for bytes, K/k for KB,
 207  * M/m for MB, G/g for GB or T/t for TB. End pointer will be returned
 208  * in *end, if not NULL. Return -ERANGE on overflow, Return -EINVAL on
 209  * other error.
 210  */
 211 int64_t qemu_strtosz_suffix_unit(const char *nptr, char **end,
 212                             const char default_suffix, int64_t unit)
 213 {
 214     int64_t retval = -EINVAL;
 215     char *endptr;
 216     unsigned char c;
 217     int mul_required = 0;
 218     double val, mul, integral, fraction;
 219
 220     errno = 0;
 221     val = strtod(nptr, &endptr);
 222     if (isnan(val) || endptr == nptr || errno != 0) {
 223         goto fail;
 224     }
 225     fraction = modf(val, &integral);
 226     if (fraction != 0) {
 227         mul_required = 1;
 228     }
 229     c = *endptr;
 230     mul = suffix_mul(c, unit);
 231     if (mul >= 0) {
 232         endptr++;
 233     } else {
 234         mul = suffix_mul(default_suffix, unit);
 235         assert(mul >= 0);
 236     }
 237     if (mul == 1 && mul_required) {
 238         goto fail;
 239     }
 240     if ((val * mul >= INT64_MAX) || val < 0) {
 241         retval = -ERANGE;
 242         goto fail;
 243     }
 244     retval = val * mul;
 245
 246 fail:
 247     if (end) {
 248         *end = endptr;
 249     }
 250
 251     return retval;
 252 }
 253
 254 int64_t qemu_strtosz_suffix(const char *nptr, char **end,
 255                             const char default_suffix)
 256 {
 257     return qemu_strtosz_suffix_unit(nptr, end, default_suffix, 1024);
 258 }
 259
 260 int64_t qemu_strtosz(const char *nptr, char **end)
 261 {
 262     return qemu_strtosz_suffix(nptr, end, QEMU_STRTOSZ_DEFSUFFIX_MB);
 263 }
 264
 265 /**
 266  * Helper function for qemu_strto*l() functions.
 267  */
 268 static int check_strtox_error(const char *p, char *endptr, const char **next,
 269                               int err)
 270 {
 271     /* If no conversion was performed, prefer BSD behavior over glibc
 272      * behavior.
 273      */
 274     if (err == 0 && endptr == p) {
 275         err = EINVAL;
 276     }
 277     if (!next && *endptr) {
 278         return -EINVAL;
 279     }
 280     if (next) {
 281         *next = endptr;
 282     }
 283     return -err;
 284 }
 285
 286 /**
 287  * QEMU wrappers for strtol(), strtoll(), strtoul(), strotull() C functions.
 288  *
 289  * Convert ASCII string @nptr to a long integer value
 290  * from the given @base. Parameters @nptr, @endptr, @base
 291  * follows same semantics as strtol() C function.
 292  *
 293  * Unlike from strtol() function, if @endptr is not NULL, this
 294  * function will return -EINVAL whenever it cannot fully convert
 295  * the string in @nptr with given @base to a long. This function returns
 296  * the result of the conversion only through the @result parameter.
 297  *
 298  * If NULL is passed in @endptr, then the whole string in @ntpr
 299  * is a number otherwise it returns -EINVAL.
 300  *
 301  * RETURN VALUE
 302  * Unlike from strtol() function, this wrapper returns either
 303  * -EINVAL or the errno set by strtol() function (e.g -ERANGE).
 304  * If the conversion overflows, -ERANGE is returned, and @result
 305  * is set to the max value of the desired type
 306  * (e.g. LONG_MAX, LLONG_MAX, ULONG_MAX, ULLONG_MAX). If the case
 307  * of underflow, -ERANGE is returned, and @result is set to the min
 308  * value of the desired type. For strtol(), strtoll(), @result is set to
 309  * LONG_MIN, LLONG_MIN, respectively, and for strtoul(), strtoull() it
 310  * is set to 0.
 311  */
 312 int qemu_strtol(const char *nptr, const char **endptr, int base,
 313                 long *result)
 314 {
 315     char *p;
 316     int err = 0;
 317     if (!nptr) {
 318         if (endptr) {
 319             *endptr = nptr;
 320         }
 321         err = -EINVAL;
 322     } else {
 323         errno = 0;
 324         *result = strtol(nptr, &p, base);
 325         err = check_strtox_error(nptr, p, endptr, errno);
 326     }
 327     return err;
 328 }
 329
 330 /**
 331  * Converts ASCII string to an unsigned long integer.
 332  *
 333  * If string contains a negative number, value will be converted to
 334  * the unsigned representation of the signed value, unless the original
 335  * (nonnegated) value would overflow, in this case, it will set @result
 336  * to ULONG_MAX, and return ERANGE.
 337  *
 338  * The same behavior holds, for qemu_strtoull() but sets @result to
 339  * ULLONG_MAX instead of ULONG_MAX.
 340  *
 341  * See qemu_strtol() documentation for more info.
 342  */
 343 int qemu_strtoul(const char *nptr, const char **endptr, int base,
 344                  unsigned long *result)
 345 {
 346     char *p;
 347     int err = 0;
 348     if (!nptr) {
 349         if (endptr) {
 350             *endptr = nptr;
 351         }
 352         err = -EINVAL;
 353     } else {
 354         errno = 0;
 355         *result = strtoul(nptr, &p, base);
 356         /* Windows returns 1 for negative out-of-range values.  */
 357         if (errno == ERANGE) {
 358             *result = -1;
 359         }
 360         err = check_strtox_error(nptr, p, endptr, errno);
 361     }
 362     return err;
 363 }
 364
 365 /**
 366  * Converts ASCII string to a long long integer.
 367  *
 368  * See qemu_strtol() documentation for more info.
 369  */
 370 int qemu_strtoll(const char *nptr, const char **endptr, int base,
 371                  int64_t *result)
 372 {
 373     char *p;
 374     int err = 0;
 375     if (!nptr) {
 376         if (endptr) {
 377             *endptr = nptr;
 378         }
 379         err = -EINVAL;
 380     } else {
 381         errno = 0;
 382         *result = strtoll(nptr, &p, base);
 383         err = check_strtox_error(nptr, p, endptr, errno);
 384     }
 385     return err;
 386 }
 387
 388 /**
 389  * Converts ASCII string to an unsigned long long integer.
 390  *
 391  * See qemu_strtol() documentation for more info.
 392  */
 393 int qemu_strtoull(const char *nptr, const char **endptr, int base,
 394                   uint64_t *result)
 395 {
 396     char *p;
 397     int err = 0;
 398     if (!nptr) {
 399         if (endptr) {
 400             *endptr = nptr;
 401         }
 402         err = -EINVAL;
 403     } else {
 404         errno = 0;
 405         *result = strtoull(nptr, &p, base);
 406         /* Windows returns 1 for negative out-of-range values.  */
 407         if (errno == ERANGE) {
 408             *result = -1;
 409         }
 410         err = check_strtox_error(nptr, p, endptr, errno);
 411     }
 412     return err;
 413 }
 414
 415 /**
 416  * parse_uint:
 417  *
 418  * @s: String to parse
 419  * @value: Destination for parsed integer value
 420  * @endptr: Destination for pointer to first character not consumed
 421  * @base: integer base, between 2 and 36 inclusive, or 0
 422  *
 423  * Parse unsigned integer
 424  *
 425  * Parsed syntax is like strtoull()'s: arbitrary whitespace, a single optional
 426  * '+' or '-', an optional "0x" if @base is 0 or 16, one or more digits.
 427  *
 428  * If @s is null, or @base is invalid, or @s doesn't start with an
 429  * integer in the syntax above, set *@value to 0, *@endptr to @s, and
 430  * return -EINVAL.
 431  *
 432  * Set *@endptr to point right beyond the parsed integer (even if the integer
 433  * overflows or is negative, all digits will be parsed and *@endptr will
 434  * point right beyond them).
 435  *
 436  * If the integer is negative, set *@value to 0, and return -ERANGE.
 437  *
 438  * If the integer overflows unsigned long long, set *@value to
 439  * ULLONG_MAX, and return -ERANGE.
 440  *
 441  * Else, set *@value to the parsed integer, and return 0.
 442  */
 443 int parse_uint(const char *s, unsigned long long *value, char **endptr,
 444                int base)
 445 {
 446     int r = 0;
 447     char *endp = (char *)s;
 448     unsigned long long val = 0;
 449
 450     if (!s) {
 451         r = -EINVAL;
 452         goto out;
 453     }
 454
 455     errno = 0;
 456     val = strtoull(s, &endp, base);
 457     if (errno) {
 458         r = -errno;
 459         goto out;
 460     }
 461
 462     if (endp == s) {
 463         r = -EINVAL;
 464         goto out;
 465     }
 466
 467     /* make sure we reject negative numbers: */
 468     while (isspace((unsigned char)*s)) {
 469         s++;
 470     }
 471     if (*s == '-') {
 472         val = 0;
 473         r = -ERANGE;
 474         goto out;
 475     }
 476
 477 out:
 478     *value = val;
 479     *endptr = endp;
 480     return r;
 481 }
 482
 483 /**
 484  * parse_uint_full:
 485  *
 486  * @s: String to parse
 487  * @value: Destination for parsed integer value
 488  * @base: integer base, between 2 and 36 inclusive, or 0
 489  *
 490  * Parse unsigned integer from entire string
 491  *
 492  * Have the same behavior of parse_uint(), but with an additional check
 493  * for additional data after the parsed number. If extra characters are present
 494  * after the parsed number, the function will return -EINVAL, and *@v will
 495  * be set to 0.
 496  */
 497 int parse_uint_full(const char *s, unsigned long long *value, int base)
 498 {
 499     char *endp;
 500     int r;
 501
 502     r = parse_uint(s, value, &endp, base);
 503     if (r < 0) {
 504         return r;
 505     }
 506     if (*endp) {
 507         *value = 0;
 508         return -EINVAL;
 509     }
 510
 511     return 0;
 512 }
 513
 514 int qemu_parse_fd(const char *param)
 515 {
 516     long fd;
 517     char *endptr;
 518
 519     errno = 0;
 520     fd = strtol(param, &endptr, 10);
 521     if (param == endptr /* no conversion performed */                    ||
 522         errno != 0      /* not representable as long; possibly others */ ||
 523         *endptr != '\0' /* final string not empty */                     ||
 524         fd < 0          /* invalid as file descriptor */                 ||
 525         fd > INT_MAX    /* not representable as int */) {
 526         return -1;
 527     }
 528     return fd;
 529 }
 530
 531 /*
 532  * Implementation of  ULEB128 (http://en.wikipedia.org/wiki/LEB128)
 533  * Input is limited to 14-bit numbers
 534  */
 535 int uleb128_encode_small(uint8_t *out, uint32_t n)
 536 {
 537     g_assert(n <= 0x3fff);
 538     if (n < 0x80) {
 539         *out++ = n;
 540         return 1;
 541     } else {
 542         *out++ = (n & 0x7f) | 0x80;
 543         *out++ = n >> 7;
 544         return 2;
 545     }
 546 }
 547
 548 int uleb128_decode_small(const uint8_t *in, uint32_t *n)
 549 {
 550     if (!(*in & 0x80)) {
 551         *n = *in++;
 552         return 1;
 553     } else {
 554         *n = *in++ & 0x7f;
 555         /* we exceed 14 bit number */
 556         if (*in & 0x80) {
 557             return -1;
 558         }
 559         *n |= *in++ << 7;
 560         return 2;
 561     }
 562 }
 563
 564 /*
 565  * helper to parse debug environment variables
 566  */
 567 int parse_debug_env(const char *name, int max, int initial)
 568 {
 569     char *debug_env = getenv(name);
 570     char *inv = NULL;
 571     long debug;
 572
 573     if (!debug_env) {
 574         return initial;
 575     }
 576     errno = 0;
 577     debug = strtol(debug_env, &inv, 10);
 578     if (inv == debug_env) {
 579         return initial;
 580     }
 581     if (debug < 0 || debug > max || errno != 0) {
 582         fprintf(stderr, "warning: %s not in [0, %d]", name, max);
 583         return initial;
 584     }
 585     return debug;
 586 }
 587
 588 /*
 589  * Helper to print ethernet mac address
 590  */
 591 const char *qemu_ether_ntoa(const MACAddr *mac)
 592 {
 593     static char ret[18];
 594
 595     snprintf(ret, sizeof(ret), "%02x:%02x:%02x:%02x:%02x:%02x",
 596              mac->a[0], mac->a[1], mac->a[2], mac->a[3], mac->a[4], mac->a[5]);
 597
 598     return ret;
 599 }