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#ifndef FILESYSTEM_FORMAT_STRING_H
10#define FILESYSTEM_FORMAT_STRING_H
11
12#include <__assert>
13#include <__config>
14#include <array>
15#include <cstdarg>
16#include <cstddef>
17#include <cstdio>
18#include <string>
19
20#if defined(_LIBCPP_WIN32API)
21# define PATHSTR(x) (L##x)
22# define PATH_CSTR_FMT "\"%ls\""
23#else
24# define PATHSTR(x) (x)
25# define PATH_CSTR_FMT "\"%s\""
26#endif
27
28_LIBCPP_BEGIN_NAMESPACE_FILESYSTEM
29
30namespace detail {
31
32inline _LIBCPP_ATTRIBUTE_FORMAT(__printf__, 1, 0) string vformat_string(const char* msg, va_list ap) {
33 array<char, 256> buf;
34
35 va_list apcopy;
36 va_copy(apcopy, ap);
37 int ret = ::vsnprintf(s: buf.data(), maxlen: buf.size(), format: msg, arg: apcopy);
38 va_end(apcopy);
39
40 string result;
41 if (static_cast<size_t>(ret) < buf.size()) {
42 result.assign(s: buf.data(), n: static_cast<size_t>(ret));
43 } else {
44 // we did not provide a long enough buffer on our first attempt. The
45 // return value is the number of bytes (excluding the null byte) that are
46 // needed for formatting.
47 size_t size_with_null = static_cast<size_t>(ret) + 1;
48 result.__resize_default_init(n: size_with_null - 1);
49 ret = ::vsnprintf(s: &result[0], maxlen: size_with_null, format: msg, arg: ap);
50 _LIBCPP_ASSERT_INTERNAL(static_cast<size_t>(ret) == (size_with_null - 1), "TODO");
51 }
52 return result;
53}
54
55inline _LIBCPP_ATTRIBUTE_FORMAT(__printf__, 1, 2) string format_string(const char* msg, ...) {
56 string ret;
57 va_list ap;
58 va_start(ap, msg);
59#if _LIBCPP_HAS_EXCEPTIONS
60 try {
61#endif // _LIBCPP_HAS_EXCEPTIONS
62 ret = detail::vformat_string(msg, ap);
63#if _LIBCPP_HAS_EXCEPTIONS
64 } catch (...) {
65 va_end(ap);
66 throw;
67 }
68#endif // _LIBCPP_HAS_EXCEPTIONS
69 va_end(ap);
70 return ret;
71}
72
73} // namespace detail
74
75_LIBCPP_END_NAMESPACE_FILESYSTEM
76
77#endif // FILESYSTEM_FORMAT_STRING_H
78