binutils-gdb/libiberty/tmpnam.c

54 lines
1.0 KiB
C

/*
@deftypefn Supplemental char* tmpnam (char *@var{s})
This function attempts to create a name for a temporary file, which
will be a valid file name yet not exist when @code{tmpnam} checks for
it. @var{s} must point to a buffer of at least @code{L_tmpnam} bytes,
or be @code{NULL}. Use of this function creates a security risk, and it must
not be used in new projects. Use @code{mkstemp} instead.
@end deftypefn
*/
#include <stdio.h>
#ifndef L_tmpnam
#define L_tmpnam 100
#endif
#ifndef P_tmpdir
#define P_tmpdir "/usr/tmp"
#endif
static char tmpnam_buffer[L_tmpnam];
static int tmpnam_counter;
extern int getpid ();
char *
tmpnam (s)
char *s;
{
int pid = getpid ();
if (s == NULL)
s = tmpnam_buffer;
/* Generate the filename and make sure that there isn't one called
it already. */
while (1)
{
FILE *f;
sprintf (s, "%s/%s%x.%x", P_tmpdir, "t", pid, tmpnam_counter);
f = fopen (s, "r");
if (f == NULL)
break;
tmpnam_counter++;
fclose (f);
}
return s;
}