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 #include "qemu/error-report.h"
  34
  35 void strpadcpy(char *buf, int buf_size, const char *str, char pad)
  36 {
  37     int len = qemu_strnlen(str, buf_size);
  38     memcpy(buf, str, len);
  39     memset(buf + len, pad, buf_size - len);
  40 }
  41
  42 void pstrcpy(char *buf, int buf_size, const char *str)
  43 {
  44     int c;
  45     char *q = buf;
  46
  47     if (buf_size <= 0)
  48         return;
  49
  50     for(;;) {
  51         c = *str++;
  52         if (c == 0 || q >= buf + buf_size - 1)
  53             break;
  54         *q++ = c;
  55     }
  56     *q = '\0';
  57 }
  58
  59 /* strcat and truncate. */
  60 char *pstrcat(char *buf, int buf_size, const char *s)
  61 {
  62     int len;
  63     len = strlen(buf);
  64     if (len < buf_size)
  65         pstrcpy(buf + len, buf_size - len, s);
  66     return buf;
  67 }
  68
  69 int strstart(const char *str, const char *val, const char **ptr)
  70 {
  71     const char *p, *q;
  72     p = str;
  73     q = val;
  74     while (*q != '\0') {
  75         if (*p != *q)
  76             return 0;
  77         p++;
  78         q++;
  79     }
  80     if (ptr)
  81         *ptr = p;
  82     return 1;
  83 }
  84
  85 int stristart(const char *str, const char *val, const char **ptr)
  86 {
  87     const char *p, *q;
  88     p = str;
  89     q = val;
  90     while (*q != '\0') {
  91         if (qemu_toupper(*p) != qemu_toupper(*q))
  92             return 0;
  93         p++;
  94         q++;
  95     }
  96     if (ptr)
  97         *ptr = p;
  98     return 1;
  99 }
 100
 101 /* XXX: use host strnlen if available ? */
 102 int qemu_strnlen(const char *s, int max_len)
 103 {
 104     int i;
 105
 106     for(i = 0; i < max_len; i++) {
 107         if (s[i] == '\0') {
 108             break;
 109         }
 110     }
 111     return i;
 112 }
 113
 114 char *qemu_strsep(char **input, const char *delim)
 115 {
 116     char *result = *input;
 117     if (result != NULL) {
 118         char *p;
 119
 120         for (p = result; *p != '\0'; p++) {
 121             if (strchr(delim, *p)) {
 122                 break;
 123             }
 124         }
 125         if (*p == '\0') {
 126             *input = NULL;
 127         } else {
 128             *p = '\0';
 129             *input = p + 1;
 130         }
 131     }
 132     return result;
 133 }
 134
 135 time_t mktimegm(struct tm *tm)
 136 {
 137     time_t t;
 138     int y = tm->tm_year + 1900, m = tm->tm_mon + 1, d = tm->tm_mday;
 139     if (m < 3) {
 140         m += 12;
 141         y--;
 142     }
 143     t = 86400ULL * (d + (153 * m - 457) / 5 + 365 * y + y / 4 - y / 100 +
 144                  y / 400 - 719469);
 145     t += 3600 * tm->tm_hour + 60 * tm->tm_min + tm->tm_sec;
 146     return t;
 147 }
 148
 149 /*
 150  * Make sure data goes on disk, but if possible do not bother to
 151  * write out the inode just for timestamp updates.
 152  *
 153  * Unfortunately even in 2009 many operating systems do not support
 154  * fdatasync and have to fall back to fsync.
 155  */
 156 int qemu_fdatasync(int fd)
 157 {
 158 #ifdef CONFIG_FDATASYNC
 159     return fdatasync(fd);
 160 #elif defined(_WIN64)
 161     /* TODO: Implement fsync for w64, too. */
 162     return NOERROR;
 163 #else
 164     return fsync(fd);
 165 #endif
 166 }
 167
 168 #ifndef _WIN32
 169 /* Sets a specific flag */
 170 int fcntl_setfl(int fd, int flag)
 171 {
 172     int flags;
 173
 174     flags = fcntl(fd, F_GETFL);
 175     if (flags == -1)
 176         return -errno;
 177
 178     if (fcntl(fd, F_SETFL, flags | flag) == -1)
 179         return -errno;
 180
 181     return 0;
 182 }
 183 #endif
 184
 185 static int64_t suffix_mul(char suffix, int64_t unit)
 186 {
 187     switch (qemu_toupper(suffix)) {
 188     case 'B':
 189         return 1;
 190     case 'K':
 191         return unit;
 192     case 'M':
 193         return unit * unit;
 194     case 'G':
 195         return unit * unit * unit;
 196     case 'T':
 197         return unit * unit * unit * unit;
 198     case 'P':
 199         return unit * unit * unit * unit * unit;
 200     case 'E':
 201         return unit * unit * unit * unit * unit * unit;
 202     }
 203     return -1;
 204 }
 205
 206 /*
 207  * Convert string to bytes, allowing either B/b for bytes, K/k for KB,
 208  * M/m for MB, G/g for GB or T/t for TB. End pointer will be returned
 209  * in *end, if not NULL. Return -ERANGE on overflow, Return -EINVAL on
 210  * other error.
 211  */
 212 static int do_strtosz(const char *nptr, char **end,
 213                       const char default_suffix, int64_t unit,
 214                       uint64_t *result)
 215 {
 216     int retval;
 217     char *endptr;
 218     unsigned char c;
 219     int mul_required = 0;
 220     double val, mul, integral, fraction;
 221
 222     errno = 0;
 223     val = strtod(nptr, &endptr);
 224     if (isnan(val) || endptr == nptr || errno != 0) {
 225         retval = -EINVAL;
 226         goto out;
 227     }
 228     fraction = modf(val, &integral);
 229     if (fraction != 0) {
 230         mul_required = 1;
 231     }
 232     c = *endptr;
 233     mul = suffix_mul(c, unit);
 234     if (mul >= 0) {
 235         endptr++;
 236     } else {
 237         mul = suffix_mul(default_suffix, unit);
 238         assert(mul >= 0);
 239     }
 240     if (mul == 1 && mul_required) {
 241         retval = -EINVAL;
 242         goto out;
 243     }
 244     /*
 245      * Values >= 0xfffffffffffffc00 overflow uint64_t after their trip
 246      * through double (53 bits of precision).
 247      */
 248     if ((val * mul >= 0xfffffffffffffc00) || val < 0) {
 249         retval = -ERANGE;
 250         goto out;
 251     }
 252     *result = val * mul;
 253     retval = 0;
 254
 255 out:
 256     if (end) {
 257         *end = endptr;
 258     } else if (*endptr) {
 259         retval = -EINVAL;
 260     }
 261
 262     return retval;
 263 }
 264
 265 int qemu_strtosz(const char *nptr, char **end, uint64_t *result)
 266 {
 267     return do_strtosz(nptr, end, 'B', 1024, result);
 268 }
 269
 270 int qemu_strtosz_MiB(const char *nptr, char **end, uint64_t *result)
 271 {
 272     return do_strtosz(nptr, end, 'M', 1024, result);
 273 }
 274
 275 int qemu_strtosz_metric(const char *nptr, char **end, uint64_t *result)
 276 {
 277     return do_strtosz(nptr, end, 'B', 1000, result);
 278 }
 279
 280 /**
 281  * Helper function for error checking after strtol() and the like
 282  */
 283 static int check_strtox_error(const char *nptr, char *ep,
 284                               const char **endptr, int libc_errno)
 285 {
 286     if (endptr) {
 287         *endptr = ep;
 288     }
 289
 290     /* Turn "no conversion" into an error */
 291     if (libc_errno == 0 && ep == nptr) {
 292         return -EINVAL;
 293     }
 294
 295     /* Fail when we're expected to consume the string, but didn't */
 296     if (!endptr && *ep) {
 297         return -EINVAL;
 298     }
 299
 300     return -libc_errno;
 301 }
 302
 303 /**
 304  * Convert string @nptr to an integer, and store it in @result.
 305  *
 306  * This is a wrapper around strtol() that is harder to misuse.
 307  * Semantics of @nptr, @endptr, @base match strtol() with differences
 308  * noted below.
 309  *
 310  * @nptr may be null, and no conversion is performed then.
 311  *
 312  * If no conversion is performed, store @nptr in *@endptr and return
 313  * -EINVAL.
 314  *
 315  * If @endptr is null, and the string isn't fully converted, return
 316  * -EINVAL.  This is the case when the pointer that would be stored in
 317  * a non-null @endptr points to a character other than '\0'.
 318  *
 319  * If the conversion overflows @result, store INT_MAX in @result,
 320  * and return -ERANGE.
 321  *
 322  * If the conversion underflows @result, store INT_MIN in @result,
 323  * and return -ERANGE.
 324  *
 325  * Else store the converted value in @result, and return zero.
 326  */
 327 int qemu_strtoi(const char *nptr, const char **endptr, int base,
 328                 int *result)
 329 {
 330     char *ep;
 331     long long lresult;
 332
 333     if (!nptr) {
 334         if (endptr) {
 335             *endptr = nptr;
 336         }
 337         return -EINVAL;
 338     }
 339
 340     errno = 0;
 341     lresult = strtoll(nptr, &ep, base);
 342     if (lresult < INT_MIN) {
 343         *result = INT_MIN;
 344         errno = ERANGE;
 345     } else if (lresult > INT_MAX) {
 346         *result = INT_MAX;
 347         errno = ERANGE;
 348     } else {
 349         *result = lresult;
 350     }
 351     return check_strtox_error(nptr, ep, endptr, errno);
 352 }
 353
 354 /**
 355  * Convert string @nptr to an unsigned integer, and store it in @result.
 356  *
 357  * This is a wrapper around strtoul() that is harder to misuse.
 358  * Semantics of @nptr, @endptr, @base match strtoul() with differences
 359  * noted below.
 360  *
 361  * @nptr may be null, and no conversion is performed then.
 362  *
 363  * If no conversion is performed, store @nptr in *@endptr and return
 364  * -EINVAL.
 365  *
 366  * If @endptr is null, and the string isn't fully converted, return
 367  * -EINVAL.  This is the case when the pointer that would be stored in
 368  * a non-null @endptr points to a character other than '\0'.
 369  *
 370  * If the conversion overflows @result, store UINT_MAX in @result,
 371  * and return -ERANGE.
 372  *
 373  * Else store the converted value in @result, and return zero.
 374  *
 375  * Note that a number with a leading minus sign gets converted without
 376  * the minus sign, checked for overflow (see above), then negated (in
 377  * @result's type).  This is exactly how strtoul() works.
 378  */
 379 int qemu_strtoui(const char *nptr, const char **endptr, int base,
 380                  unsigned int *result)
 381 {
 382     char *ep;
 383     long long lresult;
 384
 385     if (!nptr) {
 386         if (endptr) {
 387             *endptr = nptr;
 388         }
 389         return -EINVAL;
 390     }
 391
 392     errno = 0;
 393     lresult = strtoull(nptr, &ep, base);
 394
 395     /* Windows returns 1 for negative out-of-range values.  */
 396     if (errno == ERANGE) {
 397         *result = -1;
 398     } else {
 399         if (lresult > UINT_MAX) {
 400             *result = UINT_MAX;
 401             errno = ERANGE;
 402         } else if (lresult < INT_MIN) {
 403             *result = UINT_MAX;
 404             errno = ERANGE;
 405         } else {
 406             *result = lresult;
 407         }
 408     }
 409     return check_strtox_error(nptr, ep, endptr, errno);
 410 }
 411
 412 /**
 413  * Convert string @nptr to a long integer, and store it in @result.
 414  *
 415  * This is a wrapper around strtol() that is harder to misuse.
 416  * Semantics of @nptr, @endptr, @base match strtol() with differences
 417  * noted below.
 418  *
 419  * @nptr may be null, and no conversion is performed then.
 420  *
 421  * If no conversion is performed, store @nptr in *@endptr and return
 422  * -EINVAL.
 423  *
 424  * If @endptr is null, and the string isn't fully converted, return
 425  * -EINVAL.  This is the case when the pointer that would be stored in
 426  * a non-null @endptr points to a character other than '\0'.
 427  *
 428  * If the conversion overflows @result, store LONG_MAX in @result,
 429  * and return -ERANGE.
 430  *
 431  * If the conversion underflows @result, store LONG_MIN in @result,
 432  * and return -ERANGE.
 433  *
 434  * Else store the converted value in @result, and return zero.
 435  */
 436 int qemu_strtol(const char *nptr, const char **endptr, int base,
 437                 long *result)
 438 {
 439     char *ep;
 440
 441     if (!nptr) {
 442         if (endptr) {
 443             *endptr = nptr;
 444         }
 445         return -EINVAL;
 446     }
 447
 448     errno = 0;
 449     *result = strtol(nptr, &ep, base);
 450     return check_strtox_error(nptr, ep, endptr, errno);
 451 }
 452
 453 /**
 454  * Convert string @nptr to an unsigned long, and store it in @result.
 455  *
 456  * This is a wrapper around strtoul() that is harder to misuse.
 457  * Semantics of @nptr, @endptr, @base match strtoul() with differences
 458  * noted below.
 459  *
 460  * @nptr may be null, and no conversion is performed then.
 461  *
 462  * If no conversion is performed, store @nptr in *@endptr and return
 463  * -EINVAL.
 464  *
 465  * If @endptr is null, and the string isn't fully converted, return
 466  * -EINVAL.  This is the case when the pointer that would be stored in
 467  * a non-null @endptr points to a character other than '\0'.
 468  *
 469  * If the conversion overflows @result, store ULONG_MAX in @result,
 470  * and return -ERANGE.
 471  *
 472  * Else store the converted value in @result, and return zero.
 473  *
 474  * Note that a number with a leading minus sign gets converted without
 475  * the minus sign, checked for overflow (see above), then negated (in
 476  * @result's type).  This is exactly how strtoul() works.
 477  */
 478 int qemu_strtoul(const char *nptr, const char **endptr, int base,
 479                  unsigned long *result)
 480 {
 481     char *ep;
 482
 483     if (!nptr) {
 484         if (endptr) {
 485             *endptr = nptr;
 486         }
 487         return -EINVAL;
 488     }
 489
 490     errno = 0;
 491     *result = strtoul(nptr, &ep, base);
 492     /* Windows returns 1 for negative out-of-range values.  */
 493     if (errno == ERANGE) {
 494         *result = -1;
 495     }
 496     return check_strtox_error(nptr, ep, endptr, errno);
 497 }
 498
 499 /**
 500  * Convert string @nptr to an int64_t.
 501  *
 502  * Works like qemu_strtol(), except it stores INT64_MAX on overflow,
 503  * and INT_MIN on underflow.
 504  */
 505 int qemu_strtoi64(const char *nptr, const char **endptr, int base,
 506                  int64_t *result)
 507 {
 508     char *ep;
 509
 510     if (!nptr) {
 511         if (endptr) {
 512             *endptr = nptr;
 513         }
 514         return -EINVAL;
 515     }
 516
 517     errno = 0;
 518     /* FIXME This assumes int64_t is long long */
 519     *result = strtoll(nptr, &ep, base);
 520     return check_strtox_error(nptr, ep, endptr, errno);
 521 }
 522
 523 /**
 524  * Convert string @nptr to an uint64_t.
 525  *
 526  * Works like qemu_strtoul(), except it stores UINT64_MAX on overflow.
 527  */
 528 int qemu_strtou64(const char *nptr, const char **endptr, int base,
 529                   uint64_t *result)
 530 {
 531     char *ep;
 532
 533     if (!nptr) {
 534         if (endptr) {
 535             *endptr = nptr;
 536         }
 537         return -EINVAL;
 538     }
 539
 540     errno = 0;
 541     /* FIXME This assumes uint64_t is unsigned long long */
 542     *result = strtoull(nptr, &ep, base);
 543     /* Windows returns 1 for negative out-of-range values.  */
 544     if (errno == ERANGE) {
 545         *result = -1;
 546     }
 547     return check_strtox_error(nptr, ep, endptr, errno);
 548 }
 549
 550 /**
 551  * Searches for the first occurrence of 'c' in 's', and returns a pointer
 552  * to the trailing null byte if none was found.
 553  */
 554 #ifndef HAVE_STRCHRNUL
 555 const char *qemu_strchrnul(const char *s, int c)
 556 {
 557     const char *e = strchr(s, c);
 558     if (!e) {
 559         e = s + strlen(s);
 560     }
 561     return e;
 562 }
 563 #endif
 564
 565 /**
 566  * parse_uint:
 567  *
 568  * @s: String to parse
 569  * @value: Destination for parsed integer value
 570  * @endptr: Destination for pointer to first character not consumed
 571  * @base: integer base, between 2 and 36 inclusive, or 0
 572  *
 573  * Parse unsigned integer
 574  *
 575  * Parsed syntax is like strtoull()'s: arbitrary whitespace, a single optional
 576  * '+' or '-', an optional "0x" if @base is 0 or 16, one or more digits.
 577  *
 578  * If @s is null, or @base is invalid, or @s doesn't start with an
 579  * integer in the syntax above, set *@value to 0, *@endptr to @s, and
 580  * return -EINVAL.
 581  *
 582  * Set *@endptr to point right beyond the parsed integer (even if the integer
 583  * overflows or is negative, all digits will be parsed and *@endptr will
 584  * point right beyond them).
 585  *
 586  * If the integer is negative, set *@value to 0, and return -ERANGE.
 587  *
 588  * If the integer overflows unsigned long long, set *@value to
 589  * ULLONG_MAX, and return -ERANGE.
 590  *
 591  * Else, set *@value to the parsed integer, and return 0.
 592  */
 593 int parse_uint(const char *s, unsigned long long *value, char **endptr,
 594                int base)
 595 {
 596     int r = 0;
 597     char *endp = (char *)s;
 598     unsigned long long val = 0;
 599
 600     if (!s) {
 601         r = -EINVAL;
 602         goto out;
 603     }
 604
 605     errno = 0;
 606     val = strtoull(s, &endp, base);
 607     if (errno) {
 608         r = -errno;
 609         goto out;
 610     }
 611
 612     if (endp == s) {
 613         r = -EINVAL;
 614         goto out;
 615     }
 616
 617     /* make sure we reject negative numbers: */
 618     while (isspace((unsigned char)*s)) {
 619         s++;
 620     }
 621     if (*s == '-') {
 622         val = 0;
 623         r = -ERANGE;
 624         goto out;
 625     }
 626
 627 out:
 628     *value = val;
 629     *endptr = endp;
 630     return r;
 631 }
 632
 633 /**
 634  * parse_uint_full:
 635  *
 636  * @s: String to parse
 637  * @value: Destination for parsed integer value
 638  * @base: integer base, between 2 and 36 inclusive, or 0
 639  *
 640  * Parse unsigned integer from entire string
 641  *
 642  * Have the same behavior of parse_uint(), but with an additional check
 643  * for additional data after the parsed number. If extra characters are present
 644  * after the parsed number, the function will return -EINVAL, and *@v will
 645  * be set to 0.
 646  */
 647 int parse_uint_full(const char *s, unsigned long long *value, int base)
 648 {
 649     char *endp;
 650     int r;
 651
 652     r = parse_uint(s, value, &endp, base);
 653     if (r < 0) {
 654         return r;
 655     }
 656     if (*endp) {
 657         *value = 0;
 658         return -EINVAL;
 659     }
 660
 661     return 0;
 662 }
 663
 664 int qemu_parse_fd(const char *param)
 665 {
 666     long fd;
 667     char *endptr;
 668
 669     errno = 0;
 670     fd = strtol(param, &endptr, 10);
 671     if (param == endptr /* no conversion performed */                    ||
 672         errno != 0      /* not representable as long; possibly others */ ||
 673         *endptr != '\0' /* final string not empty */                     ||
 674         fd < 0          /* invalid as file descriptor */                 ||
 675         fd > INT_MAX    /* not representable as int */) {
 676         return -1;
 677     }
 678     return fd;
 679 }
 680
 681 /*
 682  * Implementation of  ULEB128 (http://en.wikipedia.org/wiki/LEB128)
 683  * Input is limited to 14-bit numbers
 684  */
 685 int uleb128_encode_small(uint8_t *out, uint32_t n)
 686 {
 687     g_assert(n <= 0x3fff);
 688     if (n < 0x80) {
 689         *out++ = n;
 690         return 1;
 691     } else {
 692         *out++ = (n & 0x7f) | 0x80;
 693         *out++ = n >> 7;
 694         return 2;
 695     }
 696 }
 697
 698 int uleb128_decode_small(const uint8_t *in, uint32_t *n)
 699 {
 700     if (!(*in & 0x80)) {
 701         *n = *in++;
 702         return 1;
 703     } else {
 704         *n = *in++ & 0x7f;
 705         /* we exceed 14 bit number */
 706         if (*in & 0x80) {
 707             return -1;
 708         }
 709         *n |= *in++ << 7;
 710         return 2;
 711     }
 712 }
 713
 714 /*
 715  * helper to parse debug environment variables
 716  */
 717 int parse_debug_env(const char *name, int max, int initial)
 718 {
 719     char *debug_env = getenv(name);
 720     char *inv = NULL;
 721     long debug;
 722
 723     if (!debug_env) {
 724         return initial;
 725     }
 726     errno = 0;
 727     debug = strtol(debug_env, &inv, 10);
 728     if (inv == debug_env) {
 729         return initial;
 730     }
 731     if (debug < 0 || debug > max || errno != 0) {
 732         warn_report("%s not in [0, %d]", name, max);
 733         return initial;
 734     }
 735     return debug;
 736 }
 737
 738 /*
 739  * Helper to print ethernet mac address
 740  */
 741 const char *qemu_ether_ntoa(const MACAddr *mac)
 742 {
 743     static char ret[18];
 744
 745     snprintf(ret, sizeof(ret), "%02x:%02x:%02x:%02x:%02x:%02x",
 746              mac->a[0], mac->a[1], mac->a[2], mac->a[3], mac->a[4], mac->a[5]);
 747
 748     return ret;
 749 }
 750
 751 /*
 752  * Return human readable string for size @val.
 753  * @val can be anything that uint64_t allows (no more than "16 EiB").
 754  * Use IEC binary units like KiB, MiB, and so forth.
 755  * Caller is responsible for passing it to g_free().
 756  */
 757 char *size_to_str(uint64_t val)
 758 {
 759     static const char *suffixes[] = { "", "Ki", "Mi", "Gi", "Ti", "Pi", "Ei" };
 760     unsigned long div;
 761     int i;
 762
 763     /*
 764      * The exponent (returned in i) minus one gives us
 765      * floor(log2(val * 1024 / 1000).  The correction makes us
 766      * switch to the higher power when the integer part is >= 1000.
 767      * (see e41b509d68afb1f for more info)
 768      */
 769     frexp(val / (1000.0 / 1024.0), &i);
 770     i = (i - 1) / 10;
 771     div = 1ULL << (i * 10);
 772
 773     return g_strdup_printf("%0.3g %sB", (double)val / div, suffixes[i]);
 774 }
 775
 776 int qemu_pstrcmp0(const char **str1, const char **str2)
 777 {
 778     return g_strcmp0(*str1, *str2);
 779 }