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
| //===-- SelectHelper.h ------------------------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
#ifndef liblldb_SelectHelper_h_
#define liblldb_SelectHelper_h_
#include "lldb/Utility/Status.h"
#include "lldb/lldb-types.h"
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/Optional.h"
#include <chrono>
class SelectHelper {
public:
// Defaults to infinite wait for select unless you call SetTimeout()
SelectHelper();
// Call SetTimeout() before calling SelectHelper::Select() to set the timeout
// based on the current time + the timeout. This allows multiple calls to
// SelectHelper::Select() without having to worry about the absolute timeout
// as this class manages to set the relative timeout correctly.
void SetTimeout(const std::chrono::microseconds &timeout);
// Call the FDSet*() functions before calling SelectHelper::Select() to set
// the file descriptors that we will watch for when calling select. This will
// cause FD_SET() to be called prior to calling select using the "fd"
// provided.
void FDSetRead(lldb::socket_t fd);
void FDSetWrite(lldb::socket_t fd);
void FDSetError(lldb::socket_t fd);
// Call the FDIsSet*() functions after calling SelectHelper::Select() to
// check which file descriptors are ready for read/write/error. This will
// contain the result of FD_ISSET after calling select for a given file
// descriptor.
bool FDIsSetRead(lldb::socket_t fd) const;
bool FDIsSetWrite(lldb::socket_t fd) const;
bool FDIsSetError(lldb::socket_t fd) const;
// Call the system's select() to wait for descriptors using timeout provided
// in a call the SelectHelper::SetTimeout(), or infinite wait if no timeout
// was set.
lldb_private::Status Select();
protected:
struct FDInfo {
FDInfo()
: read_set(false), write_set(false), error_set(false),
read_is_set(false), write_is_set(false), error_is_set(false) {}
void PrepareForSelect() {
read_is_set = false;
write_is_set = false;
error_is_set = false;
}
bool read_set : 1, write_set : 1, error_set : 1, read_is_set : 1,
write_is_set : 1, error_is_set : 1;
};
llvm::DenseMap<lldb::socket_t, FDInfo> m_fd_map;
llvm::Optional<std::chrono::steady_clock::time_point> m_end_time;
};
#endif // liblldb_SelectHelper_h_
|