// Copyright 2016 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <limits.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>

#include <zircon/compiler.h>

#include "filesystems.h"
#include "misc.h"

bool test_rename_basic(void) {
    BEGIN_TEST;
    // Cannot rename when src does not exist
    ASSERT_EQ(rename("::alpha", "::bravo"), -1, "");

    // Renaming to self is fine
    ASSERT_EQ(mkdir("::alpha", 0755), 0, "");
    ASSERT_EQ(rename("::alpha", "::alpha"), 0, "");
    ASSERT_EQ(rename("::alpha/.", "::alpha/."), 0, "");
    ASSERT_EQ(rename("::alpha/", "::alpha"), 0, "");
    ASSERT_EQ(rename("::alpha", "::alpha/"), 0, "");
    ASSERT_EQ(rename("::alpha/", "::alpha/"), 0, "");
    ASSERT_EQ(rename("::alpha/./../alpha", "::alpha/./../alpha"), 0, "");

    // Cannot rename dir to file
    int fd = open("::bravo", O_RDWR | O_CREAT | O_EXCL, 0644);
    ASSERT_GT(fd, 0, "");
    ASSERT_EQ(close(fd), 0, "");
    ASSERT_EQ(rename("::alpha", "::bravo"), -1, "");
    ASSERT_EQ(unlink("::bravo"), 0, "");

    // Rename dir (dst does not exist)
    ASSERT_EQ(rename("::alpha", "::bravo"), 0, "");
    ASSERT_EQ(mkdir("::alpha", 0755), 0, "");
    // Rename dir (dst does exist)
    ASSERT_EQ(rename("::bravo", "::alpha"), 0, "");

    // Rename file (dst does not exist)
    fd = open("::alpha/charlie", O_RDWR | O_CREAT | O_EXCL, 0644);
    ASSERT_GT(fd, 0, "");
    ASSERT_EQ(rename("::alpha/charlie", "::alpha/delta"), 0, "");
    // File rename to self
    ASSERT_EQ(rename("::alpha/delta", "::alpha/delta"), 0, "");
    // Not permitted with trailing '/'
    ASSERT_EQ(rename("::alpha/delta", "::alpha/delta/"), -1, "");
    ASSERT_EQ(rename("::alpha/delta/", "::alpha/delta"), -1, "");
    ASSERT_EQ(rename("::alpha/delta/", "::alpha/delta/"), -1, "");
    ASSERT_EQ(close(fd), 0, "");

    // Rename file (dst does not exist)
    fd = open("::alpha/charlie", O_RDWR | O_CREAT | O_EXCL, 0644);
    ASSERT_GT(fd, 0, "");
    ASSERT_EQ(rename("::alpha/delta", "::alpha/charlie"), 0, "");
    ASSERT_EQ(close(fd), 0, "");

    // Rename to different directory
    ASSERT_EQ(mkdir("::bravo", 0755), 0, "");
    ASSERT_EQ(rename("::alpha/charlie", "::charlie"), 0, "");
    ASSERT_EQ(rename("::charlie", "::alpha/charlie"), 0, "");
    ASSERT_EQ(rename("::bravo", "::alpha/bravo"), 0, "");
    ASSERT_EQ(rename("::alpha/charlie", "::alpha/bravo/charlie"), 0, "");

    // Cannot rename directory to subdirectory of itself
    ASSERT_EQ(rename("::alpha", "::alpha/bravo"), -1, "");
    ASSERT_EQ(rename("::alpha", "::alpha/bravo/charlie"), -1, "");
    ASSERT_EQ(rename("::alpha", "::alpha/bravo/charlie/delta"), -1, "");
    ASSERT_EQ(rename("::alpha", "::alpha/delta"), -1, "");
    ASSERT_EQ(rename("::alpha/bravo", "::alpha/bravo/charlie"), -1, "");
    ASSERT_EQ(rename("::alpha/bravo", "::alpha/bravo/charlie/delta"), -1, "");
    // Cannot rename to non-empty directory
    ASSERT_EQ(rename("::alpha/bravo/charlie", "::alpha/bravo"), -1, "");
    ASSERT_EQ(rename("::alpha/bravo/charlie", "::alpha"), -1, "");
    ASSERT_EQ(rename("::alpha/bravo", "::alpha"), -1, "");

    // Clean up
    ASSERT_EQ(unlink("::alpha/bravo/charlie"), 0, "");
    ASSERT_EQ(unlink("::alpha/bravo"), 0, "");
    ASSERT_EQ(unlink("::alpha"), 0, "");

    END_TEST;
}

bool test_rename_with_children(void) {
    BEGIN_TEST;

    ASSERT_EQ(mkdir("::dir_before_move", 0755), 0, "");
    ASSERT_EQ(mkdir("::dir_before_move/dir1", 0755), 0, "");
    ASSERT_EQ(mkdir("::dir_before_move/dir2", 0755), 0, "");
    ASSERT_EQ(mkdir("::dir_before_move/dir2/subdir", 0755), 0, "");
    int fd = open("::dir_before_move/file", O_RDWR | O_CREAT, 0644);
    ASSERT_GT(fd, 0, "");

    const char file_contents[] = "This should be in the file";
    ASSERT_STREAM_ALL(write, fd, (uint8_t*) file_contents, strlen(file_contents));

    ASSERT_EQ(rename("::dir_before_move", "::dir"), 0, "Could not rename");

    // Check that the directory layout has persisted across rename
    expected_dirent_t dir_contents[] = {
        {false, ".", DT_DIR},
        {false, "dir1", DT_DIR},
        {false, "dir2", DT_DIR},
        {false, "file", DT_REG},
    };
    ASSERT_TRUE(check_dir_contents("::dir", dir_contents, countof(dir_contents)), "");
    expected_dirent_t dir2_contents[] = {
        {false, ".", DT_DIR},
        {false, "subdir", DT_DIR},
    };
    ASSERT_TRUE(check_dir_contents("::dir/dir2", dir2_contents, countof(dir2_contents)), "");

    // Check the our file data has lasted (without re-opening)
    ASSERT_TRUE(check_file_contents(fd, (uint8_t*) file_contents, strlen(file_contents)), "");

    // Check the our file data has lasted (with re-opening)
    ASSERT_EQ(close(fd), 0, "");
    fd = open("::dir/file", O_RDONLY, 06444);
    ASSERT_GT(fd, 0, "");
    ASSERT_TRUE(check_file_contents(fd, (uint8_t*) file_contents, strlen(file_contents)), "");
    ASSERT_EQ(close(fd), 0, "");

    // Clean up
    ASSERT_EQ(unlink("::dir/dir1"), 0, "");
    ASSERT_EQ(unlink("::dir/dir2/subdir"), 0, "");
    ASSERT_EQ(unlink("::dir/dir2"), 0, "");
    ASSERT_EQ(unlink("::dir/file"), 0, "");
    ASSERT_EQ(unlink("::dir"), 0, "");

    END_TEST;
}

bool test_rename_absolute_relative(void) {
    BEGIN_TEST;

    char cwd[PATH_MAX];
    ASSERT_NONNULL(getcwd(cwd, sizeof(cwd)), "");

    // Change the cwd to a known directory
    ASSERT_EQ(mkdir("::working_dir", 0755), 0, "");
    DIR* dir = opendir("::working_dir");
    ASSERT_NONNULL(dir, "");
    ASSERT_EQ(chdir("::working_dir"), 0, "");

    // Make a "foo" directory in the cwd
    int fd = dirfd(dir);
    ASSERT_NE(fd, -1, "");
    ASSERT_EQ(mkdirat(fd, "foo", 0755), 0, "");
    expected_dirent_t dir_contents_foo[] = {
        {false, ".", DT_DIR},
        {false, "foo", DT_DIR},
    };
    ASSERT_TRUE(fcheck_dir_contents(dir, dir_contents_foo, countof(dir_contents_foo)), "");

    // Rename "foo" to "bar" using mixed paths
    ASSERT_EQ(rename("::working_dir/foo", "bar"), 0, "Could not rename foo to bar");
    expected_dirent_t dir_contents_bar[] = {
        {false, ".", DT_DIR},
        {false, "bar", DT_DIR},
    };
    ASSERT_TRUE(fcheck_dir_contents(dir, dir_contents_bar, countof(dir_contents_bar)), "");

    // Rename "bar" back to "foo" using mixed paths in the other direction
    ASSERT_EQ(rename("bar", "::working_dir/foo"), 0, "Could not rename bar to foo");
    ASSERT_TRUE(fcheck_dir_contents(dir, dir_contents_foo, countof(dir_contents_foo)), "");

    ASSERT_EQ(rmdir("::working_dir/foo"), 0, "");

    // Change the cwd back to the original, whatever it was before
    // this test started
    ASSERT_EQ(chdir(cwd), 0, "Could not return to original cwd");

    ASSERT_EQ(rmdir("::working_dir"), 0, "");
    ASSERT_EQ(closedir(dir), 0, "");

    END_TEST;
}

bool test_rename_at(void) {
    BEGIN_TEST;

    ASSERT_EQ(mkdir("::foo", 0755), 0, "");
    ASSERT_EQ(mkdir("::foo/baz", 0755), 0, "");
    ASSERT_EQ(mkdir("::bar", 0755), 0, "");

    // Normal case of renameat, from one directory to another
    int foofd = open("::foo", O_RDONLY | O_DIRECTORY, 0644);
    ASSERT_GT(foofd, 0, "");
    int barfd = open("::bar", O_RDONLY | O_DIRECTORY, 0644);
    ASSERT_GT(barfd, 0, "");

    ASSERT_EQ(renameat(foofd, "baz", barfd, "zab"), 0, "");

    expected_dirent_t empty_contents[] = {
        {false, ".", DT_DIR},
    };
    ASSERT_TRUE(check_dir_contents("::foo", empty_contents, countof(empty_contents)), "");
    expected_dirent_t contains_zab[] = {
        {false, ".", DT_DIR},
        {false, "zab", DT_DIR},
    };
    ASSERT_TRUE(check_dir_contents("::bar", contains_zab, countof(contains_zab)), "");

    // Alternate case of renameat, where an absolute path ignores
    // the file descriptor.
    //
    // Here, barfd is used (in the first argument) but ignored (in the second argument).
    ASSERT_EQ(renameat(barfd, "zab", barfd, "::foo/baz"), 0, "");
    expected_dirent_t contains_baz[] = {
        {false, ".", DT_DIR},
        {false, "baz", DT_DIR},
    };
    ASSERT_TRUE(check_dir_contents("::foo", contains_baz, countof(contains_baz)), "");
    ASSERT_TRUE(check_dir_contents("::bar", empty_contents, countof(empty_contents)), "");

    // The 'absolute-path-ignores-fd' case should also work with invalid fds.
    ASSERT_EQ(renameat(-1, "::foo/baz", -1, "::bar/baz"), 0, "");
    ASSERT_TRUE(check_dir_contents("::foo", empty_contents, countof(empty_contents)), "");
    ASSERT_TRUE(check_dir_contents("::bar", contains_baz, countof(contains_baz)), "");

    // However, relative paths should not be allowed with invalid fds.
    ASSERT_EQ(renameat(-1, "baz", foofd, "baz"), -1, "");
    ASSERT_EQ(errno, EBADF, "");

    // Additionally, we shouldn't be able to renameat to a file.
    int fd = openat(barfd, "filename", O_CREAT | O_RDWR | O_EXCL);
    ASSERT_GT(fd, 0, "");
    ASSERT_EQ(renameat(foofd, "baz", fd, "baz"), -1, "");
    // NOTE: not checking for "ENOTDIR", since ENOTSUPPORTED might be returned instead.

    // Clean up
    ASSERT_EQ(close(fd), 0, "");
    ASSERT_EQ(unlink("::bar/filename"), 0, "");
    ASSERT_EQ(rmdir("::bar/baz"), 0, "");
    ASSERT_EQ(close(foofd), 0, "");
    ASSERT_EQ(close(barfd), 0, "");
    ASSERT_EQ(rmdir("::foo"), 0, "");
    ASSERT_EQ(rmdir("::bar"), 0, "");
    END_TEST;
}

RUN_FOR_ALL_FILESYSTEMS(rename_tests,
    RUN_TEST_MEDIUM(test_rename_basic)
    RUN_TEST_MEDIUM(test_rename_with_children)
    RUN_TEST_MEDIUM(test_rename_absolute_relative)
    RUN_TEST_MEDIUM(test_rename_at)
)