#include "lib.h"
#include <stddef.h>
#include <stdlib.h>
#include <errno.h>
#include <time.h>
#include "posix.h"
#include "nonposix.h"
#ifndef TMP_MAX
# define TMP_MAX 238328
#endif
#if HAVE_SYS_TIME_H
# include <sys/time.h>
#endif
#ifdef HAVE_GETTIMEOFDAY
#ifdef NEED_DECLARATION_GETTIMEOFDAY
extern "C" {
int gettimeofday(struct timeval *, void *);
}
#endif
#endif
#if HAVE_CC_INTTYPES_H
# include <inttypes.h>
#endif
#if !defined UINT64_MAX && !defined uint64_t
# define uint64_t uintmax_t
#endif
static const char letters[] =
"abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789";
int gen_tempname(char *tmpl, int dir)
{
static uint64_t value;
size_t len = strlen(tmpl);
if (len < 6 || strcmp(&tmpl[len - 6], "XXXXXX"))
return -1;
char *XXXXXX = &tmpl[len - 6];
#if HAVE_GETTIMEOFDAY
timeval tv;
gettimeofday(&tv, NULL);
uint64_t random_time_bits = ((uint64_t)tv.tv_usec << 16) ^ tv.tv_sec;
#else
uint64_t random_time_bits = time(NULL);
#endif
value += random_time_bits ^ getpid();
for (int count = 0; count < TMP_MAX; value += 7777, ++count) {
uint64_t v = value;
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];
int fd = dir ? mkdir(tmpl, S_IRUSR | S_IWUSR | S_IXUSR)
: open(tmpl, O_RDWR | O_CREAT | O_EXCL, S_IRUSR | S_IWUSR);
if (fd >= 0)
return fd;
else if (errno != EEXIST)
return -1;
}
return -1;
}