glibc/libio/tst-memstream3.c

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libio: Multiple fixes for open_{w}memstram (BZ#18241 and BZ#20181) This patches fixes multiples issues on open_{w}memstream reported on both BZ#18241 and BZ#20181: - failed fseek does not set errno. - negative offset in fseek fails even when resulting position is a valid one. - a flush after write if the current write position is not at the end of the stream currupt data. The main fix is on seek operation for memstream (_IO_{w}str_seekoff), where both _IO_read_ptr and _IO_read_end pointer are updated if a write operation has occured (similar to default file operations). Also, to calculate the offset on both read and write pointers, a temporary value is instead of updating the argument supplied value. Negative offset are valid if resulting internal pointer is within the range of _IO_{read,write}_base and _IO_{read,write}_end. Also POSIX states that a null or wide null shall be appended to the current buffer iff a write moves the position to a value larger than the current lenght. Current implementation appends a null or wide null regardless of this condition. This patch fixes it by removing the 'else' condition on _IO_{w}mem_sync. Checked on x86_64. [BZ #18241] [BZ #20181] * libio/Makefile (test): Add tst-memstream3 and tst-wmemstream3. * libio/memstream.c (_IO_mem_sync): Only append a null byte if write position is at the end the buffer. * libio/wmemstream.c (_IO_wmem_sync): Likewise. * libio/strops.c (_IO_str_switch_to_get_mode): New function. (_IO_str_seekoff): Set correct offset from negative displacement and set EINVAL for invalid ones. * libio/wstrops.c (enlarge_userbuf): Use correct function to calculate buffer length. (_IO_wstr_switch_to_get_mode): New function. (_IO_wstr_seekoff): Set correct offset from negative displacement and set EINVAL for invalid ones. * libio/tst-memstream3.c: New file. * libio/tst-wmemstream3.c: Likewise. * manual/examples/memstrm.c: Remove warning when priting size_t.
2016-07-26 01:54:29 +08:00
/* Test for open_memstream implementation.
Copyright (C) 2016 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 <mcheck.h>
#include <stdio.h>
#include <string.h>
libio: Multiple fixes for open_{w}memstram (BZ#18241 and BZ#20181) This patches fixes multiples issues on open_{w}memstream reported on both BZ#18241 and BZ#20181: - failed fseek does not set errno. - negative offset in fseek fails even when resulting position is a valid one. - a flush after write if the current write position is not at the end of the stream currupt data. The main fix is on seek operation for memstream (_IO_{w}str_seekoff), where both _IO_read_ptr and _IO_read_end pointer are updated if a write operation has occured (similar to default file operations). Also, to calculate the offset on both read and write pointers, a temporary value is instead of updating the argument supplied value. Negative offset are valid if resulting internal pointer is within the range of _IO_{read,write}_base and _IO_{read,write}_end. Also POSIX states that a null or wide null shall be appended to the current buffer iff a write moves the position to a value larger than the current lenght. Current implementation appends a null or wide null regardless of this condition. This patch fixes it by removing the 'else' condition on _IO_{w}mem_sync. Checked on x86_64. [BZ #18241] [BZ #20181] * libio/Makefile (test): Add tst-memstream3 and tst-wmemstream3. * libio/memstream.c (_IO_mem_sync): Only append a null byte if write position is at the end the buffer. * libio/wmemstream.c (_IO_wmem_sync): Likewise. * libio/strops.c (_IO_str_switch_to_get_mode): New function. (_IO_str_seekoff): Set correct offset from negative displacement and set EINVAL for invalid ones. * libio/wstrops.c (enlarge_userbuf): Use correct function to calculate buffer length. (_IO_wstr_switch_to_get_mode): New function. (_IO_wstr_seekoff): Set correct offset from negative displacement and set EINVAL for invalid ones. * libio/tst-memstream3.c: New file. * libio/tst-wmemstream3.c: Likewise. * manual/examples/memstrm.c: Remove warning when priting size_t.
2016-07-26 01:54:29 +08:00
#include <stdarg.h>
#include <errno.h>
#ifndef CHAR_T
# define CHAR_T char
# define W(o) o
# define OPEN_MEMSTREAM open_memstream
# define PRINTF printf
# define FWRITE fwrite
# define FPUTC fputc
# define STRCMP strcmp
#endif
#define S(s) S1 (s)
#define S1(s) #s
static void
mcheck_abort (enum mcheck_status ev)
{
printf ("mecheck failed with status %d\n", (int) ev);
exit (1);
}
static void
error_printf (int line, const char *fmt, ...)
{
va_list ap;
printf ("error: %s:%i: ", __FILE__, line);
va_start (ap, fmt);
vprintf (fmt, ap);
va_end (ap);
}
#define ERROR_RET1(...) \
{ error_printf(__LINE__, __VA_ARGS__); return 1; }
static int
do_test_bz18241 (void)
{
CHAR_T *buf;
size_t size;
FILE *fp = OPEN_MEMSTREAM (&buf, &size);
if (fp == NULL)
ERROR_RET1 ("%s failed\n", S(OPEN_MEMSTREAM));
if (FPUTC (W('a'), fp) != W('a'))
ERROR_RET1 ("%s failed (errno = %d)\n", S(FPUTC), errno);
if (fflush (fp) != 0)
ERROR_RET1 ("fflush failed (errno = %d)\n", errno);
if (fseek (fp, -2, SEEK_SET) != -1)
ERROR_RET1 ("fseek failed (errno = %d)\n", errno);
if (errno != EINVAL)
ERROR_RET1 ("errno != EINVAL\n");
if (ftell (fp) != 1)
ERROR_RET1 ("ftell failed (errno = %d)\n", errno);
if (ferror (fp) != 0)
ERROR_RET1 ("ferror != 0\n");
if (fseek (fp, -1, SEEK_CUR) == -1)
ERROR_RET1 ("fseek failed (errno = %d)\n", errno);
if (ftell (fp) != 0)
ERROR_RET1 ("ftell failed (errno = %d)\n", errno);
if (ferror (fp) != 0)
ERROR_RET1 ("ferror != 0\n");
if (FPUTC (W('b'), fp) != W('b'))
ERROR_RET1 ("%s failed (errno = %d)\n", S(FPUTC), errno);
if (fflush (fp) != 0)
ERROR_RET1 ("fflush failed (errno = %d)\n", errno);
if (fclose (fp) != 0)
ERROR_RET1 ("fclose failed (errno = %d\n", errno);
if (STRCMP (buf, W("b")) != 0)
ERROR_RET1 ("%s failed\n", S(STRCMP));
free (buf);
return 0;
}
static int
do_test_bz20181 (void)
{
CHAR_T *buf;
size_t size;
size_t ret;
FILE *fp = OPEN_MEMSTREAM (&buf, &size);
if (fp == NULL)
ERROR_RET1 ("%s failed\n", S(OPEN_MEMSTREAM));
if ((ret = FWRITE (W("abc"), 1, 3, fp)) != 3)
ERROR_RET1 ("%s failed (errno = %d)\n", S(FWRITE), errno);
if (fseek (fp, 0, SEEK_SET) != 0)
ERROR_RET1 ("fseek failed (errno = %d)\n", errno);
if (FWRITE (W("z"), 1, 1, fp) != 1)
ERROR_RET1 ("%s failed (errno = %d)\n", S(FWRITE), errno);
if (fflush (fp) != 0)
ERROR_RET1 ("fflush failed (errno = %d)\n", errno);
/* Avoid truncating the buffer on close. */
if (fseek (fp, 3, SEEK_SET) != 0)
ERROR_RET1 ("fseek failed (errno = %d)\n", errno);
if (fclose (fp) != 0)
ERROR_RET1 ("fclose failed (errno = %d\n", errno);
if (size != 3)
ERROR_RET1 ("size != 3\n");
if (buf[0] != W('z')
|| buf[1] != W('b')
|| buf[2] != W('c'))
{
PRINTF (W("error: buf {%c,%c,%c} != {z,b,c}\n"),
buf[0], buf[1], buf[2]);
return 1;
}
free (buf);
return 0;
}
static int
do_test (void)
{
int ret = 0;
mcheck_pedantic (mcheck_abort);
ret += do_test_bz18241 ();
ret += do_test_bz20181 ();
return ret;
}
#define TEST_FUNCTION do_test ()
#include "../test-skeleton.c"