1// -*- C++ -*-
2//===----------------------------------------------------------------------===//
3//
4// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
5// See https://llvm.org/LICENSE.txt for license information.
6// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
7//
8//===----------------------------------------------------------------------===//
9
10#ifndef _LIBCPP___THREAD_FORMATTER_H
11#define _LIBCPP___THREAD_FORMATTER_H
12
13#include <__concepts/arithmetic.h>
14#include <__config>
15#include <__format/concepts.h>
16#include <__format/format_parse_context.h>
17#include <__format/formatter.h>
18#include <__format/formatter_integral.h>
19#include <__format/parser_std_format_spec.h>
20#include <__thread/id.h>
21#include <__type_traits/conditional.h>
22#include <__type_traits/is_pointer.h>
23#include <__type_traits/is_same.h>
24#include <cstdint>
25
26#if !defined(_LIBCPP_HAS_NO_PRAGMA_SYSTEM_HEADER)
27# pragma GCC system_header
28#endif
29
30#if _LIBCPP_STD_VER >= 23
31
32_LIBCPP_BEGIN_NAMESPACE_STD
33
34# if _LIBCPP_HAS_THREADS
35
36template <__fmt_char_type _CharT>
37struct formatter<__thread_id, _CharT> {
38public:
39 template <class _ParseContext>
40 _LIBCPP_HIDE_FROM_ABI constexpr typename _ParseContext::iterator parse(_ParseContext& __ctx) {
41 return __parser_.__parse(__ctx, __format_spec::__fields_fill_align_width);
42 }
43
44 template <class _FormatContext>
45 _LIBCPP_HIDE_FROM_ABI typename _FormatContext::iterator format(__thread_id __id, _FormatContext& __ctx) const {
46 // In __thread/support/pthread.h, __libcpp_thread_id is either a
47 // unsigned long long or a pthread_t.
48 //
49 // The type of pthread_t is left unspecified in POSIX so it can be any
50 // type. The most logical types are an integral or pointer.
51 // On Linux systems pthread_t is an unsigned long long.
52 // On Apple systems pthread_t is a pointer type.
53 //
54 // Note the output should match what the stream operator does. Since
55 // the ostream operator has been shipped years before this formatter
56 // was added to the Standard, this formatter does what the stream
57 // operator does. This may require platform specific changes.
58
59 using _Tp = decltype(__get_underlying_id(__id));
60 using _Cp = conditional_t<integral<_Tp>, _Tp, conditional_t<is_pointer_v<_Tp>, uintptr_t, void>>;
61 static_assert(!is_same_v<_Cp, void>, "unsupported thread::id type, please file a bug report");
62
63 __format_spec::__parsed_specifications<_CharT> __specs = __parser_.__get_parsed_std_specifications(__ctx);
64 if constexpr (is_pointer_v<_Tp>) {
65 __specs.__std_.__alternate_form_ = true;
66 __specs.__std_.__type_ = __format_spec::__type::__hexadecimal_lower_case;
67 }
68 return __formatter::__format_integer(reinterpret_cast<_Cp>(__get_underlying_id(__id)), __ctx, __specs);
69 }
70
71 __format_spec::__parser<_CharT> __parser_{.__alignment_ = __format_spec::__alignment::__right};
72};
73
74# endif // _LIBCPP_HAS_THREADS
75
76_LIBCPP_END_NAMESPACE_STD
77
78#endif // _LIBCPP_STD_VER >= 23
79
80#endif // _LIBCPP___THREAD_FORMATTER_H
81