glibc/string/test-Xnlen-nonarray.c
Florian Weimer 783d4c0b81 Enhance test coverage for strnlen, wcsnlen
This commit adds string/test-strnlen-nonarray and
wcsmbs/test-wcsnlen-nonarray.

Reviewed-by: Noah Goldstein <goldstein.w.n@gmail.com>
2024-08-01 09:07:34 +02:00

134 lines
4.7 KiB
C

/* Test non-array inputs to string length functions.
Copyright (C) 2024 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
<https://www.gnu.org/licenses/>. */
/* This skeleton file is included from string/test-strnlen-nonarray.c
and wcsmbs/test-wcsnlen-nonarray.c to test that reading of the array
stops at the first null character.
TEST_IDENTIFIER must be the test function identifier. TEST_NAME is
the same as a string.
CHAR must be defined as the character type. */
#include <array_length.h>
#include <string.h>
#include <support/check.h>
#include <support/next_to_fault.h>
#include <support/test-driver.h>
#include <sys/param.h>
#include <unistd.h>
typedef __typeof (TEST_IDENTIFIER) *proto_t;
#define TEST_MAIN
#include "test-string.h"
IMPL (TEST_IDENTIFIER, 1)
static int
test_main (void)
{
enum { buffer_length = 256 };
TEST_VERIFY_EXIT (sysconf (_SC_PAGESIZE) >= buffer_length);
test_init ();
/* Buffer layout: There are a_count 'A' character followed by
zero_count null character, for a total of buffer_length
character:
AAAAA...AAAAA 00000 ... 00000 (unmapped page follows)
\ / \ /
(a_count) (zero_count)
\___ (buffer_length) ___/
^
|
start_offset
The buffer length does not change, but a_count (and thus _zero)
and start_offset vary.
If start_offset == buffer_length, only 0 is a valid length
argument. The result is 0.
Otherwwise, if zero_count > 0 (if there a null characters in the
buffer), then any length argument is valid. If start_offset <
a_count (i.e., there is a non-null character at start_offset), the
result is the minimum of a_count - start_offset and the length
argument. Otherwise the result is 0.
Otherwise, there are no null characters before the unmapped page.
The length argument must not be greater than buffer_length -
start_offset, and the result is the length argument. */
struct support_next_to_fault ntf
= support_next_to_fault_allocate (buffer_length * sizeof (CHAR));
CHAR *buffer = (CHAR *) ntf.buffer;
FOR_EACH_IMPL (impl, 0)
{
printf ("info: testing %s\n", impl->name);
for (size_t i = 0; i < buffer_length; ++i)
buffer[i] = 'A';
for (int zero_count = 0; zero_count <= buffer_length; ++zero_count)
{
if (zero_count > 0)
buffer[buffer_length - zero_count] = 0;
int a_count = buffer_length - zero_count;
for (int start_offset = 0; start_offset <= buffer_length;
++start_offset)
{
CHAR *start_pointer = buffer + start_offset;
if (start_offset == buffer_length)
TEST_COMPARE (CALL (impl, buffer + start_offset, 0), 0);
else if (zero_count > 0)
for (int length_argument = 0;
length_argument <= 2 * buffer_length;
++length_argument)
{
if (test_verbose)
printf ("zero_count=%d a_count=%d start_offset=%d"
" length_argument=%d\n",
zero_count, a_count, start_offset,
length_argument);
if (start_offset < a_count)
TEST_COMPARE (CALL (impl, start_pointer, length_argument),
MIN (a_count - start_offset,
length_argument));
else
TEST_COMPARE (CALL (impl, start_pointer, length_argument),
0);
}
else
for (int length_argument = 0;
length_argument <= buffer_length - start_offset;
++length_argument)
TEST_COMPARE (CALL (impl, start_pointer, length_argument),
length_argument);
}
}
}
support_next_to_fault_free (&ntf);
return 0;
}
#include <support/test-driver.c>