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#532570
int__gen_tempname (char *tmpl, int kind){ int len; char *XXXXXX; static uint64_t value; uint64_t random_time_bits; unsigned int count; int fd = -1; int save_errno = errno; struct_stat64 st; /* A lower bound on the number of temporary files to attempt to generate. The maximum total number of temporary file names that can exist for a given template is 62**6. It should never be necessary to try all these combinations. Instead if a reasonable number of names is tried (we define reasonable as 62**3) fail to give the system administrator the chance to remove the problems. */#define ATTEMPTS_MIN (62 * 62 * 62) /* The number of times to attempt to generate a temporary file. To conform to POSIX, this must be no smaller than TMP_MAX. */#if ATTEMPTS_MIN < TMP_MAX unsigned int attempts = TMP_MAX;#else unsigned int attempts = ATTEMPTS_MIN;#endif len = strlen (tmpl); if (len < 6 || strcmp (&tmpl[len - 6], "XXXXXX")) { __set_errno (EINVAL); return -1; } /* This is where the Xs start. */ XXXXXX = &tmpl[len - 6]; /* Get some more or less random data. */#ifdef RANDOM_BITS RANDOM_BITS (random_time_bits);#else# if HAVE_GETTIMEOFDAY || _LIBC { struct timeval tv; __gettimeofday (&tv, NULL); random_time_bits = ((uint64_t) tv.tv_usec << 16) ^ tv.tv_sec; }# else random_time_bits = time (NULL);# endif#endif value += random_time_bits ^ __getpid (); for (count = 0; count < attempts; value += 7777, ++count) { uint64_t v = value; /* Fill in the random bits. */ XXXXXX[0] = letters[v % 62]; v /= 62; XXXXXX[1] = letters[v % 62]; v /= 62; XXXXXX[2] = letters[v % 62]; v /= 62; XXXXXX[3] = letters[v % 62]; v /= 62; XXXXXX[4] = letters[v % 62]; v /= 62; XXXXXX[5] = letters[v % 62]; switch (kind) { case __GT_FILE: fd = __open (tmpl, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR); break; case __GT_BIGFILE: fd = __open64 (tmpl, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR); break; case __GT_DIR: fd = __mkdir (tmpl, S_IRUSR | S_IWUSR | S_IXUSR); break; case __GT_NOCREATE: /* This case is backward from the other three. __gen_tempname succeeds if __xstat fails because the name does not exist. Note the continue to bypass the common logic at the bottom of the loop. */ if (__lxstat64 (_STAT_VER, tmpl, &st) < 0) { if (errno == ENOENT) { __set_errno (save_errno); return 0; } else /* Give up now. */ return -1; } continue; default: assert (! "invalid KIND in __gen_tempname"); } if (fd >= 0) { __set_errno (save_errno); return fd; } else if (errno != EEXIST) return -1; } /* We got out of the loop because we ran out of combinations to try. */ __set_errno (EEXIST); return -1;}