1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
|
// file : butl/diagnostics -*- C++ -*-
// copyright : Copyright (c) 2014-2017 Code Synthesis Ltd
// license : MIT; see accompanying LICENSE file
#ifndef BUTL_DIAGNOSTICS
#define BUTL_DIAGNOSTICS
#include <cassert>
#include <ostream>
#include <sstream>
#include <utility> // move(), forward()
#include <exception> // uncaught_exception(s)()
#include <butl/export>
#include <butl/utility>
namespace butl
{
// Diagnostic facility base infrastructure.
//
LIBBUTL_EXPORT extern std::ostream* diag_stream; // std::cerr by default.
struct diag_record;
template <typename> struct diag_prologue;
template <typename> struct diag_mark;
using diag_epilogue = void (const diag_record&);
struct LIBBUTL_EXPORT diag_record
{
template <typename T>
friend const diag_record&
operator<< (const diag_record& r, const T& x)
{
r.os << x;
return r;
}
diag_record ()
:
#ifdef BUTL_CXX17_UNCAUGHT_EXCEPTIONS
uncaught_ (std::uncaught_exceptions ()),
#endif
empty_ (true),
epilogue_ (nullptr) {}
template <typename B>
explicit
diag_record (const diag_prologue<B>& p): diag_record () { *this << p;}
template <typename B>
explicit
diag_record (const diag_mark<B>& m): diag_record () { *this << m;}
~diag_record () noexcept (false);
bool
empty () const {return empty_;}
bool
full () const {return !empty_;}
void
flush () const;
void
append (diag_epilogue* e) const
{
if (e != nullptr)
{
assert (epilogue_ == nullptr); // No multiple epilogues support.
epilogue_ = e;
}
if (empty_)
empty_ = false;
else
os << "\n ";
}
// Move constructible-only type.
//
// Older versions of libstdc++ don't have the ostringstream move support
// and accuratly detecting its version is non-trivial. So we always use
// the pessimized implementation with libstdc++. Luckily, GCC doesn't seem
// to be needing move due to copy/move elision.
//
#ifdef __GLIBCXX__
diag_record (diag_record&&);
#else
diag_record (diag_record&& r)
:
#ifdef BUTL_CXX17_UNCAUGHT_EXCEPTIONS
uncaught_ (r.uncaught_),
#endif
empty_ (r.empty_),
epilogue_ (r.epilogue_),
os (std::move (r.os))
{
if (!empty_)
{
r.empty_ = true;
r.epilogue_ = nullptr;
}
}
#endif
diag_record& operator= (diag_record&&) = delete;
diag_record (const diag_record&) = delete;
diag_record& operator= (const diag_record&) = delete;
protected:
#ifdef BUTL_CXX17_UNCAUGHT_EXCEPTIONS
const int uncaught_;
#endif
mutable bool empty_;
mutable diag_epilogue* epilogue_;
public:
mutable std::ostringstream os;
};
template <typename B>
struct diag_prologue: B
{
diag_prologue (diag_epilogue* e = nullptr): B (), epilogue_ (e) {}
template <typename... A>
diag_prologue (A&&... a)
: B (std::forward<A> (a)...), epilogue_ (nullptr) {}
template <typename... A>
diag_prologue (diag_epilogue* e, A&&... a)
: B (std::forward<A> (a)...), epilogue_ (e) {}
template <typename T>
diag_record
operator<< (const T& x) const
{
diag_record r;
r.append (epilogue_);
B::operator() (r);
r << x;
return r;
}
friend const diag_record&
operator<< (const diag_record& r, const diag_prologue& p)
{
r.append (p.epilogue_);
p (r);
return r;
}
private:
diag_epilogue* epilogue_;
};
template <typename B>
struct diag_mark: B
{
diag_mark (): B () {}
template <typename... A>
diag_mark (A&&... a): B (std::forward<A> (a)...) {}
template <typename T>
diag_record
operator<< (const T& x) const
{
return B::operator() () << x;
}
friend const diag_record&
operator<< (const diag_record& r, const diag_mark& m)
{
return r << m ();
}
};
template <typename B>
struct diag_noreturn_end: B
{
diag_noreturn_end (): B () {}
template <typename... A>
diag_noreturn_end (A&&... a): B (std::forward<A> (a)...) {}
[[noreturn]] friend void
operator<< (const diag_record& r, const diag_noreturn_end& e)
{
// We said that we never return which means this end mark cannot be used
// to "maybe not return". And not returning without any diagnostics is
// probably a mistake.
//
assert (r.full ());
e.B::operator() (r);
}
};
}
#endif // BUTL_DIAGNOSTICS
|
