ladybird/Tests/LibC/TestRealpath.cpp
sin-ack c70f45ff44 Everywhere: Explicitly specify the size in StringView constructors
This commit moves the length calculations out to be directly on the
StringView users. This is an important step towards the goal of removing
StringView(char const*), as it moves the responsibility of calculating
the size of the string to the user of the StringView (which will prevent
naive uses causing OOB access).
2022-07-12 23:11:35 +02:00

86 lines
3 KiB
C++

/*
* Copyright (c) 2021, Ben Wiederhake <BenWiederhake.GitHub@gmx.de>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <LibTest/TestCase.h>
#include <AK/String.h>
#include <AK/StringBuilder.h>
#include <errno.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <unistd.h>
static constexpr char TMPDIR_PATTERN[] = "/tmp/overlong_realpath_XXXXXX";
static constexpr char PATH_LOREM_250[] = "This-is-an-annoyingly-long-name-that-should-take-up-exactly-two-hundred-and-fifty-characters-and-is-surprisingly-difficult-to-fill-with-reasonably-meaningful-text-which-is-necessary-because-that-makes-it-easier-for-my-eyes-to-spot-any-corruption-fast";
static constexpr size_t ITERATION_DEPTH = 17;
static void check_result(char const* what, String const& expected, char const* actual)
{
if (expected != actual)
FAIL(String::formatted("Expected {} to be \"{}\" ({} characters)", what, actual, actual ? strlen(actual) : 0));
}
TEST_CASE(overlong_realpath)
{
// We want to construct a path that is over PATH_MAX characters long.
// This cannot be done in a single step.
// First, switch to a known environment:
char tmp_dir[] = "/tmp/overlong_realpath_XXXXXX";
errno = 0;
auto* new_dir = mkdtemp(tmp_dir);
VERIFY(new_dir != nullptr);
VERIFY(errno == 0);
errno = 0;
auto ret = chdir(tmp_dir);
VERIFY(ret >= 0);
VERIFY(errno == 0);
// Then, create a long path.
StringBuilder expected;
expected.append({ tmp_dir, strlen(tmp_dir) });
// But first, demonstrate the functionality at a reasonable depth:
auto expected_str = expected.build();
check_result("getwd", expected_str, getwd(static_cast<char*>(calloc(1, PATH_MAX))));
check_result("getcwd", expected_str, getcwd(nullptr, 0));
check_result("realpath", expected_str, realpath(".", nullptr));
for (size_t i = 0; i < ITERATION_DEPTH; ++i) {
ret = mkdir(PATH_LOREM_250, S_IRWXU);
if (ret < 0) {
perror("mkdir iter");
FAIL(String::formatted("Unable to mkdir the overlong path fragment in iteration {}", i));
return;
}
expected.append('/');
expected.append({ PATH_LOREM_250, strlen(PATH_LOREM_250) });
ret = chdir(PATH_LOREM_250);
if (ret < 0) {
perror("chdir iter");
FAIL(String::formatted("Unable to chdir to the overlong path fragment in iteration {}", i));
return;
}
}
outln("cwd should now be ridiculously large");
// Evaluate
expected_str = expected.build();
check_result("getwd", {}, getwd(static_cast<char*>(calloc(1, PATH_MAX))));
check_result("getcwd", expected_str, getcwd(nullptr, 0));
check_result("realpath", expected_str, realpath(".", nullptr));
VERIFY(strlen(PATH_LOREM_250) == 250);
VERIFY(strlen(TMPDIR_PATTERN) + ITERATION_DEPTH * (1 + strlen(PATH_LOREM_250)) == expected_str.length());
VERIFY(expected_str.length() > PATH_MAX);
}