/* Verify that ftell returns the correct value at various points before and
after the handler on which it is called becomes active.
Copyright (C) 2014-2018 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <errno.h>
#include <unistd.h>
#include <fcntl.h>
#include <locale.h>
#include <wchar.h>
static int do_test (void);
#define TEST_FUNCTION do_test ()
#include "../test-skeleton.c"
#define get_handles_fdopen(filename, fd, fp, fd_mode, mode) \
({ \
int ret = 0; \
(fd) = open ((filename), (fd_mode), 0); \
if ((fd) == -1) \
{ \
printf ("open failed: %m\n"); \
ret = 1; \
} \
else \
{ \
(fp) = fdopen ((fd), (mode)); \
if ((fp) == NULL) \
{ \
printf ("fdopen failed: %m\n"); \
close (fd); \
ret = 1; \
} \
} \
ret; \
})
#define get_handles_fopen(filename, fd, fp, mode) \
({ \
int ret = 0; \
(fp) = fopen ((filename), (mode)); \
if ((fp) == NULL) \
{ \
printf ("fopen failed: %m\n"); \
ret = 1; \
} \
else \
{ \
(fd) = fileno (fp); \
if ((fd) == -1) \
{ \
printf ("fileno failed: %m\n"); \
ret = 1; \
} \
} \
ret; \
})
/* data points to either char_data or wide_data, depending on whether we're
testing regular file mode or wide mode respectively. Similarly,
fputs_func points to either fputs or fputws. data_len keeps track of the
length of the current data and file_len maintains the current file
length. */
static const void *data;
static const char *char_data = "abcdef";
static const wchar_t *wide_data = L"abcdef";
static size_t data_len;
static size_t file_len;
typedef int (*fputs_func_t) (const void *data, FILE *fp);
typedef void *(*fgets_func_t) (void *ws, int n, FILE *fp);
fputs_func_t fputs_func;
fgets_func_t fgets_func;
/* This test verifies that the offset reported by ftell is correct after the
file is truncated using ftruncate. ftruncate does not change the file
offset on truncation and hence, SEEK_CUR should continue to point to the
old offset and not be changed to the new offset. */
static int
do_ftruncate_test (const char *filename)
{
FILE *fp = NULL;
int fd;
int ret = 0;
struct test
{
const char *mode;
int fd_mode;
} test_modes[] = {
{"r+", O_RDWR},
{"w", O_WRONLY | O_TRUNC},
{"w+", O_RDWR | O_TRUNC},
{"a", O_WRONLY},
{"a+", O_RDWR}
};
for (int j = 0; j < 2; j++)
{
for (int i = 0; i < sizeof (test_modes) / sizeof (struct test); i++)
{
int fileret;
printf ("\tftruncate: %s (file, \"%s\"): ",
j == 0 ? "fopen" : "fdopen",
test_modes[i].mode);
if (j == 0)
fileret = get_handles_fopen (filename, fd, fp, test_modes[i].mode);
else
fileret = get_handles_fdopen (filename, fd, fp,
test_modes[i].fd_mode,
test_modes[i].mode);
if (fileret != 0)
return fileret;
/* Write some data. */
size_t written = fputs_func (data, fp);
if (written == EOF)
{
printf ("fputs[1] failed to write data\n");
ret |= 1;
}
/* Record the offset. */
long offset = ftell (fp);
/* Flush data to allow switching active handles. */
if (fflush (fp))
{
printf ("Flush failed: %m\n");
ret |= 1;
}
/* Now truncate the file. */
if (ftruncate (fd, 0) != 0)
{
printf ("Failed to truncate file: %m\n");
ret |= 1;
}
/* ftruncate does not change the offset, so there is no need to call
anything to be able to switch active handles. */
long new_offset = ftell (fp);
/* The offset should remain unchanged since ftruncate does not update
it. */
if (offset != new_offset)
{
printf ("Incorrect offset. Expected %ld, but got %ld\n",
offset, new_offset);
ret |= 1;
}
else
printf ("offset = %ld\n", offset);
fclose (fp);
}
}
return ret;
}
/* Test that ftell output after a rewind is correct. */
static int
do_rewind_test (const char *filename)
{
int ret = 0;
struct test
{
const char *mode;
int fd_mode;
size_t old_off;
size_t new_off;
} test_modes[] = {
{"w", O_WRONLY | O_TRUNC, 0, data_len},
{"w+", O_RDWR | O_TRUNC, 0, data_len},
{"r+", O_RDWR, 0, data_len},
/* The new offsets for 'a' and 'a+' modes have to factor in the
previous writes since they always append to the end of the
file. */
{"a", O_WRONLY, 0, 3 * data_len},
{"a+", O_RDWR, 0, 4 * data_len},
};
/* Empty the file before the test so that our offsets are simple to
calculate. */
FILE *fp = fopen (filename, "w");
if (fp == NULL)
{
printf ("Failed to open file for emptying\n");
return 1;
}
fclose (fp);
for (int j = 0; j < 2; j++)
{
for (int i = 0; i < sizeof (test_modes) / sizeof (struct test); i++)
{
FILE *fp;
int fd;
int fileret;
printf ("\trewind: %s (file, \"%s\"): ", j == 0 ? "fdopen" : "fopen",
test_modes[i].mode);
if (j == 0)
fileret = get_handles_fdopen (filename, fd, fp,
test_modes[i].fd_mode,
test_modes[i].mode);
else
fileret = get_handles_fopen (filename, fd, fp, test_modes[i].mode);
if (fileret != 0)
return fileret;
/* Write some content to the file, rewind and ensure that the ftell
output after the rewind is 0. POSIX does not specify what the
behavior is when a file is rewound in 'a' mode, so we retain
current behavior, which is to keep the 0 offset. */
size_t written = fputs_func (data, fp);
if (written == EOF)
{
printf ("fputs[1] failed to write data\n");
ret |= 1;
}
rewind (fp);
long offset = ftell (fp);
if (offset != test_modes[i].old_off)
{
printf ("Incorrect old offset. Expected %zu, but got %ld, ",
test_modes[i].old_off, offset);
ret |= 1;
}
else
printf ("old offset = %ld, ", offset);
written = fputs_func (data, fp);
if (written == EOF)
{
printf ("fputs[1] failed to write data\n");
ret |= 1;
}
/* After this write, the offset in append modes should factor in the
implicit lseek to the end of file. */
offset = ftell (fp);
if (offset != test_modes[i].new_off)
{
printf ("Incorrect new offset. Expected %zu, but got %ld\n",
test_modes[i].new_off, offset);
ret |= 1;
}
else
printf ("new offset = %ld\n", offset);
}
}
return ret;
}
/* Test that the value of ftell is not cached when the stream handle is not
active. */
static int
do_ftell_test (const char *filename)
{
int ret = 0;
struct test
{
const char *mode;
int fd_mode;
size_t old_off;
size_t new_off;
size_t eof_off;
} test_modes[] = {
/* In w, w+ and r+ modes, the file position should be at the
beginning of the file. After the write, the offset should be
updated to data_len. We don't use eof_off in w and a modes since
they don't allow reading. */
{"w", O_WRONLY | O_TRUNC, 0, data_len, 0},
{"w+", O_RDWR | O_TRUNC, 0, data_len, 2 * data_len},
{"r+", O_RDWR, 0, data_len, 3 * data_len},
/* For the 'a' mode, the initial file position should be the
current end of file. After the write, the offset has data_len
added to the old value. For a+ mode however, the initial file
position is the file position of the underlying file descriptor,
since it is initially assumed to be in read mode. */
{"a", O_WRONLY, 3 * data_len, 4 * data_len, 5 * data_len},
{"a+", O_RDWR, 0, 5 * data_len, 6 * data_len},
};
for (int j = 0; j < 2; j++)
{
for (int i = 0; i < sizeof (test_modes) / sizeof (struct test); i++)
{
FILE *fp;
int fd;
int fileret;
printf ("\tftell: %s (file, \"%s\"): ", j == 0 ? "fdopen" : "fopen",
test_modes[i].mode);
if (j == 0)
fileret = get_handles_fdopen (filename, fd, fp,
test_modes[i].fd_mode,
test_modes[i].mode);
else
fileret = get_handles_fopen (filename, fd, fp, test_modes[i].mode);
if (fileret != 0)
return fileret;
long off = ftell (fp);
if (off != test_modes[i].old_off)
{
printf ("Incorrect old offset. Expected %zu but got %ld, ",
test_modes[i].old_off, off);
ret |= 1;
}
else
printf ("old offset = %ld, ", off);
/* The effect of this write on the offset should be seen in the ftell
call that follows it. */
int write_ret = write (fd, data, data_len);
if (write_ret != data_len)
{
printf ("write failed (%m)\n");
ret |= 1;
}
off = ftell (fp);
if (off != test_modes[i].new_off)
{
printf ("Incorrect new offset. Expected %zu but got %ld",
test_modes[i].new_off, off);
ret |= 1;
}
else
printf ("new offset = %ld", off);
/* Read to the end, write some data to the fd and check if ftell can
see the new ofset. Do this test only for files that allow
reading. */
if (test_modes[i].fd_mode != O_WRONLY)
{
wchar_t tmpbuf[data_len];
rewind (fp);
while (fgets_func (tmpbuf, data_len, fp) && !feof (fp));
write_ret = write (fd, data, data_len);
if (write_ret != data_len)
{
printf ("write failed (%m)\n");
ret |= 1;
}
off = ftell (fp);
if (off != test_modes[i].eof_off)
{
printf (", Incorrect offset after read EOF. "
"Expected %zu but got %ld\n",
test_modes[i].eof_off, off);
ret |= 1;
}
else
printf (", offset after EOF = %ld\n", off);
}
else
putc ('\n', stdout);
fclose (fp);
}
}
return ret;
}
/* This test opens the file for writing, moves the file offset of the
underlying file, writes out data and then checks if ftell trips on it. */
static int
do_write_test (const char *filename)
{
FILE *fp = NULL;
int fd;
int ret = 0;
struct test
{
const char *mode;
int fd_mode;
} test_modes[] = {
{"w", O_WRONLY | O_TRUNC},
{"w+", O_RDWR | O_TRUNC},
{"r+", O_RDWR}
};
for (int j = 0; j < 2; j++)
{
for (int i = 0; i < sizeof (test_modes) / sizeof (struct test); i++)
{
int fileret;
printf ("\twrite: %s (file, \"%s\"): ", j == 0 ? "fopen" : "fdopen",
test_modes[i].mode);
if (j == 0)
fileret = get_handles_fopen (filename, fd, fp, test_modes[i].mode);
else
fileret = get_handles_fdopen (filename, fd, fp,
test_modes[i].fd_mode,
test_modes[i].mode);
if (fileret != 0)
return fileret;
/* Move offset to just before the end of the file. */
off_t seek_ret = lseek (fd, file_len - 1, SEEK_SET);
if (seek_ret == -1)
{
printf ("lseek failed: %m\n");
ret |= 1;
}
/* Write some data. */
size_t written = fputs_func (data, fp);
if (written == EOF)
{
printf ("fputs[1] failed to write data\n");
ret |= 1;
}
/* Verify that the offset points to the end of the file. The length
of the file would be the original length + the length of data
written to it - the amount by which we moved the offset using
lseek. */
long offset = ftell (fp);
file_len = file_len - 1 + data_len;
if (offset != file_len)
{
printf ("Incorrect offset. Expected %zu, but got %ld\n",
file_len, offset);
ret |= 1;
}
printf ("offset = %ld\n", offset);
fclose (fp);
}
}
return ret;
}
/* This test opens a file in append mode, writes some data, and then verifies
that ftell does not trip over it. */
static int
do_append_test (const char *filename)
{
FILE *fp = NULL;
int ret = 0;
int fd;
struct test
{
const char *mode;
int fd_mode;
} test_modes[] = {
{"a", O_WRONLY},
{"a+", O_RDWR}
};
for (int j = 0; j < 2; j++)
{
for (int i = 0; i < sizeof (test_modes) / sizeof (struct test); i++)
{
int fileret;
printf ("\tappend: %s (file, \"%s\"): ", j == 0 ? "fopen" : "fdopen",
test_modes[i].mode);
if (j == 0)
fileret = get_handles_fopen (filename, fd, fp, test_modes[i].mode);
else
fileret = get_handles_fdopen (filename, fd, fp,
test_modes[i].fd_mode,
test_modes[i].mode);
if (fileret != 0)
return fileret;
/* Write some data. */
size_t written = fputs_func (data, fp);
if (written == EOF)
{
printf ("fputs[1] failed to write all data\n");
ret |= 1;
}
/* Verify that the offset points to the end of the file. The file
len is maintained by adding data_len each time to reflect the data
written to it. */
long offset = ftell (fp);
file_len += data_len;
if (offset != file_len)
{
printf ("Incorrect offset. Expected %zu, but got %ld\n",
file_len, offset);
ret |= 1;
}
printf ("offset = %ld\n", offset);
fclose (fp);
}
}
/* For fdopen in 'a' mode, the file descriptor should not change if the file
is already open with the O_APPEND flag set. */
fd = open (filename, O_WRONLY | O_APPEND, 0);
if (fd == -1)
{
printf ("open(O_APPEND) failed: %m\n");
return 1;
}
off_t seek_ret = lseek (fd, file_len - 1, SEEK_SET);
if (seek_ret == -1)
{
printf ("lseek[O_APPEND][0] failed: %m\n");
ret |= 1;
}
fp = fdopen (fd, "a");
if (fp == NULL)
{
printf ("fdopen(O_APPEND) failed: %m\n");
close (fd);
return 1;
}
off_t new_seek_ret = lseek (fd, 0, SEEK_CUR);
if (seek_ret == -1)
{
printf ("lseek[O_APPEND][1] failed: %m\n");
ret |= 1;
}
printf ("\tappend: fdopen (file, \"a\"): O_APPEND: ");
if (seek_ret != new_seek_ret)
{
printf ("incorrectly modified file offset to %jd, should be %jd",
(intmax_t) new_seek_ret, (intmax_t) seek_ret);
ret |= 1;
}
else
printf ("retained current file offset %jd", (intmax_t) seek_ret);
new_seek_ret = ftello (fp);
if (seek_ret != new_seek_ret)
{
printf (", ftello reported incorrect offset %jd, should be %jd\n",
(intmax_t) new_seek_ret, (intmax_t) seek_ret);
ret |= 1;
}
else
printf (", ftello reported correct offset %jd\n", (intmax_t) seek_ret);
fclose (fp);
return ret;
}
static int
do_one_test (const char *filename)
{
int ret = 0;
ret |= do_ftell_test (filename);
ret |= do_write_test (filename);
ret |= do_append_test (filename);
ret |= do_rewind_test (filename);
ret |= do_ftruncate_test (filename);
return ret;
}
/* Run a set of tests for ftell for regular files and wide mode files. */
static int
do_test (void)
{
int ret = 0;
FILE *fp = NULL;
char *filename;
size_t written;
int fd = create_temp_file ("tst-active-handler-tmp.", &filename);
if (fd == -1)
{
printf ("create_temp_file: %m\n");
return 1;
}
fp = fdopen (fd, "w");
if (fp == NULL)
{
printf ("fdopen[0]: %m\n");
close (fd);
return 1;
}
data = char_data;
data_len = strlen (char_data);
file_len = strlen (char_data);
written = fputs (data, fp);
if (written == EOF)
{
printf ("fputs[1] failed to write data\n");
ret = 1;
}
fclose (fp);
if (ret)
return ret;
/* Tests for regular files. */
puts ("Regular mode:");
fputs_func = (fputs_func_t) fputs;
fgets_func = (fgets_func_t) fgets;
data = char_data;
data_len = strlen (char_data);
ret |= do_one_test (filename);
/* Truncate the file before repeating the tests in wide mode. */
fp = fopen (filename, "w");
if (fp == NULL)
{
printf ("fopen failed %m\n");
return 1;
}
fclose (fp);
/* Tests for wide files. */
puts ("Wide mode:");
if (setlocale (LC_ALL, "en_US.UTF-8") == NULL)
{
printf ("Cannot set en_US.UTF-8 locale.\n");
return 1;
}
fputs_func = (fputs_func_t) fputws;
fgets_func = (fgets_func_t) fgetws;
data = wide_data;
data_len = wcslen (wide_data);
ret |= do_one_test (filename);
return ret;
}