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mleleszimleleszi
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Implement faccessat
1 parent 80beefa commit 5522dcc

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10 files changed

+272
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‎libc/config/linux/aarch64/entrypoints.txt‎

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@@ -325,6 +325,7 @@ set(TARGET_LIBC_ENTRYPOINTS
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libc.src.unistd.dup2
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libc.src.unistd.dup3
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libc.src.unistd.execve
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libc.src.unistd.faccessat
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libc.src.unistd.fchdir
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libc.src.unistd.fpathconf
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libc.src.unistd.fsync

‎libc/config/linux/x86_64/entrypoints.txt‎

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@@ -331,6 +331,7 @@ set(TARGET_LIBC_ENTRYPOINTS
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libc.src.unistd.dup2
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libc.src.unistd.dup3
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libc.src.unistd.execve
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libc.src.unistd.faccessat
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libc.src.unistd.fchdir
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libc.src.unistd.fpathconf
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libc.src.unistd.fsync

‎libc/include/llvm-libc-macros/linux/fcntl-macros.h‎

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@@ -61,6 +61,9 @@
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// Allow empty relative pathname.
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#define AT_EMPTY_PATH 0x1000
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// Perform access checks using the effective user and group IDs.
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#define AT_EACCESS
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// Values of SYS_fcntl commands.
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#define F_DUPFD 0
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#define F_GETFD 1

‎libc/include/unistd.yaml‎

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@@ -96,6 +96,15 @@ functions:
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- type: const char *
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- type: __exec_argv_t
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- type: __exec_envp_t
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- name: faccessat
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standards:
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- POSIX
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return_type: int
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arguments:
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- type: int
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- type: const char *
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- type: int
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- type: int
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- name: fchdir
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standards:
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- POSIX

‎libc/src/unistd/CMakeLists.txt‎

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@@ -55,6 +55,13 @@ add_entrypoint_object(
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.${LIBC_TARGET_OS}.dup3
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)
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add_entrypoint_object(
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faccessat
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ALIAS
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DEPENDS
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.${LIBC_TARGET_OS}.faccessat
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)
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add_entrypoint_object(
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fchdir
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ALIAS

‎libc/src/unistd/faccessat.h‎

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//===-- Implementation header for faccessat ------------------------*- C++ -*-===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_LIBC_SRC_UNISTD_FACCESSAT_H
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#define LLVM_LIBC_SRC_UNISTD_FACCESSAT_H
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#include "src/__support/macros/config.h"
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namespace LIBC_NAMESPACE_DECL {
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int faccessat(int fd, const char *path, int amode, int flag);
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} // namespace LIBC_NAMESPACE_DECL
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#endif // LLVM_LIBC_SRC_UNISTD_FACCESSAT_H

‎libc/src/unistd/linux/CMakeLists.txt‎

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@@ -80,6 +80,20 @@ add_entrypoint_object(
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libc.src.errno.errno
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)
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add_entrypoint_object(
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faccessat
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SRCS
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faccessat.cpp
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HDRS
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../faccessat.h
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DEPENDS
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libc.hdr.fcntl_macros
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libc.include.unistd
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libc.include.sys_syscall
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libc.src.__support.OSUtil.osutil
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libc.src.errno.errno
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)
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add_entrypoint_object(
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fchdir
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SRCS

‎libc/src/unistd/linux/faccessat.cpp‎

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//===-- Linux implementation of faccessat ------------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#include "src/unistd/faccessat.h"
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#include "src/__support/OSUtil/syscall.h" // For internal syscall function.
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#include "src/__support/common.h"
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#include "hdr/fcntl_macros.h"
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#include "src/__support/libc_errno.h"
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#include "src/__support/macros/config.h"
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#include <sys/syscall.h> // For syscall numbers.
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namespace LIBC_NAMESPACE_DECL {
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LLVM_LIBC_FUNCTION(int, faccessat, (int fd, const char *path, int amode, int flag)) {
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#ifdef SYS_faccessat2
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int ret = LIBC_NAMESPACE::syscall_impl<int>(SYS_faccessat2, fd, path, amode, flag);
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#else
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#error "faccessat2 syscall is not available."
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#endif
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if (ret < 0) {
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libc_errno = -ret;
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return -1;
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}
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return 0;
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}
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} // namespace LIBC_NAMESPACE_DECL

‎libc/test/src/unistd/CMakeLists.txt‎

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@@ -93,6 +93,28 @@ add_libc_unittest(
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libc.test.UnitTest.ErrnoSetterMatcher
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)
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add_libc_unittest(
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faccessat_test
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SUITE
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libc_unistd_unittests
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SRCS
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faccessat_test.cpp
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DEPENDS
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libc.include.unistd
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libc.src.__support.CPP.string
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libc.src.sys.stat.mkdir
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libc.src.errno.errno
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libc.src.fcntl.open
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libc.src.unistd.faccessat
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libc.src.unistd.close
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libc.src.unistd.symlink
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libc.src.unistd.unlink
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libc.src.unistd.unlinkat
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libc.src.unistd.rmdir
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libc.test.UnitTest.ErrnoCheckingTest
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libc.test.UnitTest.ErrnoSetterMatcher
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)
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add_libc_unittest(
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fchdir_test
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SUITE

‎libc/test/src/unistd/faccessat_test.cpp‎

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//===-- Unittests for faccessat -------------------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#include "src/fcntl/open.h"
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#include "src/__support/CPP/string.h"
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#include "src/sys/stat/mkdir.h"
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#include "src/unistd/faccessat.h"
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#include "src/unistd/close.h"
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#include "src/unistd/unlink.h"
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#include "src/unistd/unlinkat.h"
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#include "src/unistd/symlink.h"
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#include "src/unistd/rmdir.h"
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#include "src/unistd/symlink.h"
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#include "test/UnitTest/ErrnoCheckingTest.h"
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#include "test/UnitTest/ErrnoSetterMatcher.h"
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#include "test/UnitTest/Test.h"
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#include <fcntl.h> // For AT_FDCWD, AT_EACCESS, AT_SYMLINK_NOFOLLOW
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#include <sys/stat.h> // For S_IRWXU, S_IXUSR, etc.
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#include <unistd.h> // For F_OK, R_OK, W_OK, X_OK
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namespace {
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using LIBC_NAMESPACE::testing::ErrnoSetterMatcher::Succeeds;
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using LIBC_NAMESPACE::testing::ErrnoSetterMatcher::Fails;
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class LlvmLibcFaccessatTest : public LIBC_NAMESPACE::testing::ErrnoCheckingTest {
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public:
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void create_test_dir(const char* dirname, int& dir_fd) {
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auto TEST_DIR = libc_make_test_file_path(dirname);
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ASSERT_THAT(LIBC_NAMESPACE::mkdir(TEST_DIR, S_IRWXU), Succeeds(0));
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dir_fd = LIBC_NAMESPACE::open(TEST_DIR, O_RDONLY | O_DIRECTORY);
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ASSERT_ERRNO_SUCCESS();
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ASSERT_GT(dir_fd, 0);
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}
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void cleanup_test_dir(const char* dirname, int dir_fd) {
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auto TEST_DIR = libc_make_test_file_path(dirname);
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ASSERT_THAT(LIBC_NAMESPACE::close(dir_fd), Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::rmdir(TEST_DIR), Succeeds(0));
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}
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};
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TEST_F(LlvmLibcFaccessatTest, CreateAndTest_AT_FDCWD) {
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// Test access checks on a file with AT_FDCWD, equivalent to access().
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constexpr const char *FILENAME = "faccessat_basic3.test";
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auto TEST_FILE = libc_make_test_file_path(FILENAME);
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// Create file with full permissions
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int fd = LIBC_NAMESPACE::open(TEST_FILE, O_WRONLY | O_CREAT, S_IRWXU);
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ASSERT_ERRNO_SUCCESS();
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ASSERT_GT(fd, 0);
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ASSERT_THAT(LIBC_NAMESPACE::close(fd), Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::faccessat(AT_FDCWD, TEST_FILE, F_OK, 0), Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::faccessat(AT_FDCWD, TEST_FILE, X_OK | W_OK | R_OK, 0),
66+
Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::unlink(TEST_FILE), Succeeds(0));
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// Create file with execute-only permission
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fd = LIBC_NAMESPACE::open(TEST_FILE, O_WRONLY | O_CREAT, S_IXUSR);
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ASSERT_ERRNO_SUCCESS();
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ASSERT_GT(fd, 0);
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ASSERT_THAT(LIBC_NAMESPACE::close(fd), Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::faccessat(AT_FDCWD, TEST_FILE, F_OK, 0), Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::faccessat(AT_FDCWD, TEST_FILE, X_OK, 0), Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::faccessat(AT_FDCWD, TEST_FILE, R_OK, 0), Fails(EACCES));
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ASSERT_THAT(LIBC_NAMESPACE::faccessat(AT_FDCWD, TEST_FILE, W_OK, 0), Fails(EACCES));
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ASSERT_THAT(LIBC_NAMESPACE::unlink(TEST_FILE), Succeeds(0));
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}
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TEST_F(LlvmLibcFaccessatTest, RelativePathWithDirFD) {
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LIBC_NAMESPACE::cpp::string DIRNAME ="faccessat_dir3";
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LIBC_NAMESPACE::cpp::string FILENAME = "relative_file3.txt";
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int dir_fd;
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create_test_dir(DIRNAME.data(), dir_fd);
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auto FULL_FILE_PATH = libc_make_test_file_path((DIRNAME + "/" + FILENAME).data());
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int fd = LIBC_NAMESPACE::open(FULL_FILE_PATH, O_WRONLY | O_CREAT, S_IRWXU);
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ASSERT_ERRNO_SUCCESS();
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ASSERT_GT(fd, 0);
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ASSERT_THAT(LIBC_NAMESPACE::close(fd), Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::faccessat(dir_fd, FILENAME.data(), R_OK | W_OK, 0), Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::unlinkat(dir_fd, FILENAME.data(), 0), Succeeds(0));
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cleanup_test_dir(DIRNAME.data(), dir_fd);
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}
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TEST_F(LlvmLibcFaccessatTest, SymlinkNoFollow) {
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constexpr const char *TARGET = "faccessat_target2";
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constexpr const char *SYMLINK = "faccessat_link2";
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auto TEST_TARGET = libc_make_test_file_path(TARGET);
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auto TEST_SYMLINK = libc_make_test_file_path(SYMLINK);
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int fd = LIBC_NAMESPACE::open(TEST_TARGET, O_WRONLY | O_CREAT, 0);
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ASSERT_ERRNO_SUCCESS();
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ASSERT_GT(fd, 0);
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ASSERT_THAT(LIBC_NAMESPACE::close(fd), Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::symlink(TARGET, TEST_SYMLINK), Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::faccessat(AT_FDCWD, TEST_SYMLINK, R_OK, 0), Fails(EACCES));
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ASSERT_THAT(LIBC_NAMESPACE::faccessat(AT_FDCWD, TEST_SYMLINK, F_OK, AT_SYMLINK_NOFOLLOW), Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::unlink(TEST_SYMLINK), Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::unlink(TEST_TARGET), Succeeds(0));
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}
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TEST_F(LlvmLibcFaccessatTest, AtEaccess) {
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// With AT_EACCESS, faccessat checks permissions using the effective user ID,
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// but the effective and real user ID will be the same here and changing that is not feasible in a test,
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// so this is just a basic sanity check.
125+
constexpr const char *FILENAME = "faccessat_eaccess.test";
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auto TEST_FILE = libc_make_test_file_path(FILENAME);
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int fd = LIBC_NAMESPACE::open(TEST_FILE, O_WRONLY | O_CREAT, S_IRWXU);
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ASSERT_ERRNO_SUCCESS();
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ASSERT_GT(fd, 0);
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ASSERT_THAT(LIBC_NAMESPACE::close(fd), Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::faccessat(AT_FDCWD, TEST_FILE, X_OK | W_OK | R_OK, AT_EACCESS),
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Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::unlink(TEST_FILE), Succeeds(0));
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}
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TEST_F(LlvmLibcFaccessatTest, AtEmptyPath) {
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constexpr const char *FILENAME = "faccessat_atemptypath.test";
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auto TEST_FILE = libc_make_test_file_path(FILENAME);
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int fd = LIBC_NAMESPACE::open(TEST_FILE, O_WRONLY | O_CREAT, S_IRWXU);
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ASSERT_ERRNO_SUCCESS();
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ASSERT_GT(fd, 0);
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ASSERT_THAT(LIBC_NAMESPACE::faccessat(fd, "", F_OK, AT_EMPTY_PATH), Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::faccessat(fd, "", X_OK | W_OK | R_OK, AT_EMPTY_PATH),
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Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::close(fd), Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::unlink(TEST_FILE), Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::faccessat(AT_FDCWD, "", F_OK, AT_EMPTY_PATH), Succeeds(0));
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ASSERT_THAT(LIBC_NAMESPACE::faccessat(AT_FDCWD, "", X_OK | W_OK | R_OK, AT_EMPTY_PATH),
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Succeeds(0));
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}
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} // namespace

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