Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
Browse files
Browse the repository at this point in the history
2002-07-24 Roland McGrath <roland@frob.com>
* libio/Makefile (tests): Add bug-ungetc. * libio/bug-ungetc.c: New file.
- Loading branch information
Roland McGrath
committed
Jul 24, 2002
1 parent
29f6bb6
commit 0e94c21
Showing
2 changed files
with
62 additions
and
1 deletion.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Original file line number | Diff line number | Diff line change |
---|---|---|
@@ -0,0 +1,61 @@ | ||
/* Test program for ungetc/ftell interaction bug. */ | ||
|
||
#include <stdio.h> | ||
|
||
static void do_prepare (void); | ||
#define PREPARE(argc, argv) do_prepare () | ||
static int do_test (void); | ||
#define TEST_FUNCTION do_test () | ||
#include <test-skeleton.c> | ||
|
||
static const char pattern[] = "12345"; | ||
static char *temp_file; | ||
|
||
static void | ||
do_prepare (void) | ||
{ | ||
int fd = create_temp_file ("bug-ungetc.", &temp_file); | ||
if (fd == -1) | ||
{ | ||
printf ("cannot create temporary file: %m\n"); | ||
exit (1); | ||
} | ||
write (fd, pattern, sizeof (pattern)); | ||
close (fd); | ||
} | ||
|
||
static int | ||
do_test (void) | ||
{ | ||
int i; | ||
FILE *f; | ||
char buf[10]; | ||
long offset, diff; | ||
int result = 0; | ||
|
||
f = fopen (temp_file, "rw"); | ||
|
||
rewind (f); | ||
for (i = 0; i < 3; i++) | ||
printf ("%c\n", getc (f)); | ||
offset = ftell (f); | ||
printf ("offset = %ld\n", offset); | ||
if (ungetc ('4', f) != '4') | ||
{ | ||
printf ("ungetc failed\n"); | ||
abort (); | ||
} | ||
printf ("offset after ungetc = %ld\n", ftell (f)); | ||
|
||
i = fread ((void *) buf, 4, (size_t) 1, f); | ||
printf ("read %d (%c), offset = %ld\n", i, buf[0], ftell (f)); | ||
diff = ftell (f) - offset; | ||
if (diff != 3) | ||
{ | ||
printf ("ftell did not update properly. got %ld, expected 3\n", diff); | ||
result = 1; | ||
} | ||
fclose (f); | ||
|
||
return result; | ||
} |