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
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
|
/*
* Copyright 2014 Daniel Vrátil <dvratil@redhat.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of
* the License or (at your option) version 3 or any later version
* accepted by the membership of KDE e.V. (or its successor approved
* by the membership of KDE e.V.), which shall act as a proxy
* defined in Section 14 of version 3 of the license.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*
*/
#ifndef ASYNC_H
#define ASYNC_H
#include <functional>
#include <list>
#include <type_traits>
#include <iostream>
#include <cassert>
#include <iterator>
#include <boost/graph/graph_concepts.hpp>
#include "future.h"
#include "async_impl.h"
namespace Async {
template<typename PrevOut, typename Out, typename ... In>
class Executor;
class JobBase;
template<typename Out, typename ... In>
class Job;
template<typename Out, typename ... In>
using ThenTask = typename detail::identity<std::function<void(In ..., Async::Future<Out>&)>>::type;
template<typename Out, typename In>
using EachTask = typename detail::identity<std::function<void(In, Async::Future<Out>&)>>::type;
template<typename Out, typename In>
using ReduceTask = typename detail::identity<std::function<void(In, Async::Future<Out>&)>>::type;
namespace Private
{
template<typename ... T>
struct PreviousOut {
using type = typename std::tuple_element<0, std::tuple<T ..., void>>::type;
};
class ExecutorBase
{
template<typename PrevOut, typename Out, typename ... In>
friend class Executor;
public:
virtual ~ExecutorBase();
virtual void exec() = 0;
inline FutureBase* result() const
{
return mResult;
}
protected:
ExecutorBase(ExecutorBase *parent);
ExecutorBase *mPrev;
FutureBase *mResult;
};
template<typename PrevOut, typename Out, typename ... In>
class Executor : public ExecutorBase
{
protected:
Executor(ExecutorBase *parent)
: ExecutorBase(parent)
{}
virtual ~Executor() {}
inline Async::Future<PrevOut>* chainup();
std::function<void(const In& ..., Async::Future<Out> &)> mFunc;
};
template<typename Out, typename ... In>
class ThenExecutor: public Executor<typename PreviousOut<In ...>::type, Out, In ...>
{
public:
ThenExecutor(ThenTask<Out, In ...> then, ExecutorBase *parent = nullptr);
void exec();
};
template<typename PrevOut, typename Out, typename In>
class EachExecutor : public Executor<PrevOut, Out, In>
{
public:
EachExecutor(EachTask<Out, In> each, ExecutorBase *parent);
void exec();
};
template<typename Out, typename In>
class ReduceExecutor : public Executor<In, Out, In>
{
public:
ReduceExecutor(ReduceTask<Out, In> reduce, ExecutorBase *parent);
void exec();
};
} // namespace Private
class JobBase
{
template<typename Out, typename ... In>
friend class Job;
public:
JobBase(Private::ExecutorBase *executor);
~JobBase();
void exec();
protected:
Private::ExecutorBase *mExecutor;
};
template<typename Out, typename ... In>
class Job : public JobBase
{
template<typename OutOther, typename ... InOther>
friend class Job;
template<typename OutOther, typename ... InOther>
friend Job<OutOther, InOther ...> start(Async::ThenTask<OutOther, InOther ...> func);
public:
template<typename OutOther, typename ... InOther>
Job<OutOther, InOther ...> then(ThenTask<OutOther, InOther ...> func)
{
return Job<OutOther, InOther ...>(new Private::ThenExecutor<OutOther, InOther ...>(func, mExecutor));
}
template<typename OutOther, typename InOther>
Job<OutOther, InOther> each(EachTask<OutOther, InOther> func)
{
static_assert(detail::isIterable<Out>::value,
"The 'Each' task can only be connected to a job that returns a list or an array.");
static_assert(detail::isIterable<OutOther>::value,
"The result type of 'Each' task must be a list or an array.");
return Job<OutOther, InOther>(new Private::EachExecutor<Out, OutOther, InOther>(func, mExecutor));
}
template<typename OutOther, typename InOther>
Job<OutOther, InOther> reduce(ReduceTask<OutOther, InOther> func)
{
static_assert(Async::detail::isIterable<Out>::value,
"The 'Result' task can only be connected to a job that returns a list or an array");
static_assert(std::is_same<typename Out::value_type, typename InOther::value_type>::value,
"The return type of previous task must be compatible with input type of this task");
return Job<OutOther, InOther>(new Private::ReduceExecutor<OutOther, InOther>(func, mExecutor));
}
Async::Future<Out> result() const
{
return *static_cast<Async::Future<Out>*>(mExecutor->result());
}
private:
Job(Private::ExecutorBase *executor)
: JobBase(executor)
{
}
};
} // namespace Async
// ********** Out of line definitions ****************
namespace Async {
template<typename Out, typename ... In>
Job<Out, In ...> start(ThenTask<Out, In ...> func)
{
return Job<Out, In ...>(new Private::ThenExecutor<Out, In ...>(func));
}
namespace Private {
template<typename PrevOut, typename Out, typename ... In>
Future<PrevOut>* Executor<PrevOut, Out, In ...>::chainup()
{
if (mPrev) {
mPrev->exec();
auto future = static_cast<Async::Future<PrevOut>*>(mPrev->result());
assert(future->isFinished());
return future;
} else {
return 0;
}
}
template<typename Out, typename ... In>
ThenExecutor<Out, In ...>::ThenExecutor(ThenTask<Out, In ...> then, ExecutorBase* parent)
: Executor<typename PreviousOut<In ...>::type, Out, In ...>(parent)
{
this->mFunc = then;
}
template<typename Out, typename ... In>
void ThenExecutor<Out, In ...>::exec()
{
auto in = this->chainup();
(void)in; // supress 'unused variable' warning when In is void
auto out = new Async::Future<Out>();
this->mFunc(in ? in->value() : In() ..., *out);
out->waitForFinished();
this->mResult = out;
}
template<typename PrevOut, typename Out, typename In>
EachExecutor<PrevOut, Out, In>::EachExecutor(EachTask<Out, In> each, ExecutorBase* parent)
: Executor<PrevOut, Out, In>(parent)
{
this->mFunc = each;
}
template<typename PrevOut, typename Out, typename In>
void EachExecutor<PrevOut, Out, In>::exec()
{
auto in = this->chainup();
auto *out = new Async::Future<Out>();
for (auto arg : in->value()) {
Async::Future<Out> future;
this->mFunc(arg, future);
future.waitForFinished();
out->setValue(out->value() + future.value());
}
out->setFinished();
this->mResult = out;
}
template<typename Out, typename In>
ReduceExecutor<Out, In>::ReduceExecutor(ReduceTask<Out, In> reduce, ExecutorBase* parent)
: Executor<In, Out, In>(parent)
{
this->mFunc = reduce;
}
template<typename Out, typename In>
void ReduceExecutor<Out, In>::exec()
{
auto in = this->chainup();
auto out = new Async::Future<Out>();
this->mFunc(in->value(), *out);
out->waitForFinished();
this->mResult = out;
}
} // namespace Private
} // namespace Async
#endif // ASYNC_H
|
