1//===-- Unittests for dup -------------------------------------------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8
9#include "src/errno/libc_errno.h"
10#include "src/fcntl/open.h"
11#include "src/unistd/close.h"
12#include "src/unistd/dup2.h"
13#include "src/unistd/read.h"
14#include "src/unistd/unlink.h"
15#include "src/unistd/write.h"
16#include "test/UnitTest/ErrnoSetterMatcher.h"
17#include "test/UnitTest/Test.h"
18
19#include <sys/stat.h>
20
21TEST(LlvmLibcdupTest, ReadAndWriteViaDup) {
22 constexpr int DUPFD = 0xD0;
23 LIBC_NAMESPACE::libc_errno = 0;
24 using LIBC_NAMESPACE::testing::ErrnoSetterMatcher::Succeeds;
25 constexpr const char *FILENAME = "dup2.test";
26 auto TEST_FILE = libc_make_test_file_path(FILENAME);
27 int fd = LIBC_NAMESPACE::open(path: TEST_FILE, O_WRONLY | O_CREAT, S_IRWXU);
28 ASSERT_ERRNO_SUCCESS();
29 ASSERT_GT(fd, 0);
30 int dupfd = LIBC_NAMESPACE::dup2(oldfd: fd, newfd: DUPFD);
31 ASSERT_ERRNO_SUCCESS();
32 ASSERT_EQ(dupfd, DUPFD);
33
34 // Write something via the dup
35 constexpr char WRITE_DATA[] = "Hello, dup!";
36 constexpr size_t WRITE_SIZE = sizeof(WRITE_DATA);
37 ASSERT_EQ(ssize_t(WRITE_SIZE),
38 LIBC_NAMESPACE::write(dupfd, WRITE_DATA, WRITE_SIZE));
39 ASSERT_THAT(LIBC_NAMESPACE::close(dupfd), Succeeds(0));
40
41 // Reopen the file for reading and create a dup.
42 fd = LIBC_NAMESPACE::open(path: TEST_FILE, O_RDONLY);
43 ASSERT_ERRNO_SUCCESS();
44 ASSERT_GT(fd, 0);
45 dupfd = LIBC_NAMESPACE::dup2(oldfd: fd, newfd: DUPFD);
46 ASSERT_ERRNO_SUCCESS();
47 ASSERT_EQ(dupfd, DUPFD);
48
49 // Read the file content via the dup.
50 char buf[WRITE_SIZE];
51 ASSERT_THAT(LIBC_NAMESPACE::read(dupfd, buf, WRITE_SIZE),
52 Succeeds(WRITE_SIZE));
53 ASSERT_STREQ(buf, WRITE_DATA);
54
55 // Verify that duping to the same fd value succeeds.
56 ASSERT_THAT(LIBC_NAMESPACE::dup2(dupfd, dupfd), Succeeds(dupfd));
57
58 ASSERT_THAT(LIBC_NAMESPACE::close(dupfd), Succeeds(0));
59 ASSERT_THAT(LIBC_NAMESPACE::unlink(TEST_FILE), Succeeds(0));
60}
61
62TEST(LlvmLibcdupTest, DupBadFD) {
63 using LIBC_NAMESPACE::testing::ErrnoSetterMatcher::Fails;
64 ASSERT_THAT(LIBC_NAMESPACE::dup2(-1, 123), Fails(EBADF));
65}
66

source code of libc/test/src/unistd/dup2_test.cpp