1 //===----------------------------------------------------------------------===//
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 // <fstream>
10 
11 // basic_filebuf<charT,traits>* close();
12 
13 #include <fstream>
14 #include <cassert>
15 #if defined(__unix__)
16 #include <fcntl.h>
17 #include <unistd.h>
18 #endif
19 #include "test_macros.h"
20 #include "platform_support.h"
21 
main(int,char **)22 int main(int, char**)
23 {
24     std::string temp = get_temp_file_name();
25     {
26         std::filebuf f;
27         assert(!f.is_open());
28         assert(f.open(temp.c_str(), std::ios_base::out) != 0);
29         assert(f.is_open());
30         assert(f.close() != nullptr);
31         assert(!f.is_open());
32         assert(f.close() == nullptr);
33         assert(!f.is_open());
34     }
35 #if defined(__unix__)
36     {
37         std::filebuf f;
38         assert(!f.is_open());
39         // Use open directly to get the file descriptor.
40         int fd = open(temp.c_str(), O_RDWR);
41         assert(fd >= 0);
42         // Use the internal method to create filebuf from the file descriptor.
43         assert(f.__open(fd, std::ios_base::out) != 0);
44         assert(f.is_open());
45         // Close the file descriptor directly to force filebuf::close to fail.
46         assert(close(fd) == 0);
47         // Ensure that filebuf::close handles the failure.
48         assert(f.close() == nullptr);
49         assert(!f.is_open());
50         assert(f.close() == nullptr);
51     }
52 #endif
53     std::remove(temp.c_str());
54 
55     return 0;
56 }
57