glibc/stdio-common/tst-fdopen.c
Joseph Myers 5c112f1b62 Avoid insecure usage of tmpnam in tests.
Various glibc testcases use tmpnam in ways subject to race conditions
(generate a temporary file name, then later open that file without
O_EXCL).

This patch fixes those tests to use mkstemp - generally a minimal
local fix to use mkstemp instead of tmpnam, rather than a larger fix
to use other testsuite infrastructure for temporary files.  The
unchanged use of tmpnam in posix/wordexp-test.c would fail safe in the
event of a race (it's generating a name for use with mkdir rather than
for a file to be opened for writing).

Tested for x86_64.

	* grp/tst_fgetgrent.c: Include <unistd.h>.
	(main): Use mkstemp instead of tmpnam.
	* io/test-utime.c (main): Likewise.
	* posix/annexc.c (macrofile): Change to modifiable array.
	(get_null_defines): Use mkstemp instead of tmpnam.  Do not remove
	macrofile here.
	* posix/bug-getopt1.c: Include <stdlib.h>.
	(do_test): Use mkstemp instead of tmpnam.
	* posix/bug-getopt2.c: Include <stdlib.h>.
	(do_test): Use mkstemp instead of tmpnam.
	* posix/bug-getopt3.c: Include <stdlib.h>.
	(do_test): Use mkstemp instead of tmpnam.
	* posix/bug-getopt4.c: Include <stdlib.h>.
	(do_test): Use mkstemp instead of tmpnam.
	* posix/bug-getopt5.c: Include <stdlib.h>.
	(do_test): Use mkstemp instead of tmpnam.
	* stdio-common/bug7.c: Include <stdlib.h> and <unistd.h>.
	(main): Use mkstemp instead of tmpnam.
	* stdio-common/tst-fdopen.c: Include <stdlib.h>.
	(main): Use mkstemp instead of tmpnam.
	* stdio-common/tst-ungetc.c: Include <stdlib.h>.
	(main): use mkstemp instead of tmpnam.
	* stdlib/isomac.c (macrofile): Change to modifiable array.
	(get_null_defines): Use mkstemp instead of tmpnam.  Do not remove
	macrofile here.
2018-07-18 21:04:12 +00:00

58 lines
1.1 KiB
C

/* Test for fdopen bugs. */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#undef assert
#define assert(x) \
if (!(x)) \
{ \
fputs ("test failed: " #x "\n", stderr); \
retval = 1; \
goto the_end; \
}
char buffer[256];
int
main (int argc, char *argv[])
{
char name[] = "/tmp/tst-fdopen.XXXXXX";
FILE *fp = NULL;
int retval = 0;
int fd;
fd = mkstemp (name);
if (fd == -1)
{
printf ("mkstemp failed: %m\n");
return 1;
}
close (fd);
fp = fopen (name, "w");
assert (fp != NULL)
fputs ("foobar and baz", fp);
fclose (fp);
fp = NULL;
fd = open (name, O_RDONLY);
assert (fd != -1);
assert (lseek (fd, 5, SEEK_SET) == 5);
/* The file position indicator associated with the new stream is set to
the position indicated by the file offset associated with the file
descriptor. */
fp = fdopen (fd, "r");
assert (fp != NULL);
assert (getc (fp) == 'r');
assert (getc (fp) == ' ');
the_end:
if (fp != NULL)
fclose (fp);
unlink (name);
return retval;
}