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
|
// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef CHROMEOS_PROCESS_PROXY_PROCESS_OUTPUT_WATCHER_H_
#define CHROMEOS_PROCESS_PROXY_PROCESS_OUTPUT_WATCHER_H_
#include <stddef.h>
#include <memory>
#include <string>
#include "base/component_export.h"
#include "base/files/file.h"
#include "base/files/file_descriptor_watcher_posix.h"
#include "base/functional/callback.h"
#include "base/memory/weak_ptr.h"
namespace chromeos {
enum ProcessOutputType {
PROCESS_OUTPUT_TYPE_OUT,
PROCESS_OUTPUT_TYPE_EXIT
};
using ProcessOutputCallback =
base::RepeatingCallback<void(ProcessOutputType, const std::string&)>;
// Observes output on |out_fd| and invokes |callback| when some output is
// detected. It assumes UTF8 output.
class COMPONENT_EXPORT(CHROMEOS_PROCESS_PROXY) ProcessOutputWatcher {
public:
ProcessOutputWatcher(int out_fd, const ProcessOutputCallback& callback);
ProcessOutputWatcher(const ProcessOutputWatcher&) = delete;
ProcessOutputWatcher& operator=(const ProcessOutputWatcher&) = delete;
~ProcessOutputWatcher();
void Start();
void AckOutput();
base::WeakPtr<ProcessOutputWatcher> GetWeakPtr() {
return weak_factory_.GetWeakPtr();
}
private:
// Called when |process_output_file_| is readable without blocking.
void OnProcessOutputCanReadWithoutBlocking();
// Listens to output from fd passed to the constructor.
void WatchProcessOutput();
// Reads data from fd and invokes callback |on_read_callback_| with read data.
void ReadFromFd(int fd);
// Checks if the read buffer has any trailing incomplete UTF8 characters and
// returns the read buffer size without them.
size_t OutputSizeWithoutIncompleteUTF8();
// Processes new |read_buffer_| state and notifies observer about new process
// output.
void ReportOutput(ProcessOutputType type, size_t new_bytes_count);
char read_buffer_[4096];
// Maximum read buffer content size.
size_t read_buffer_capacity_;
// Current read bufferi content size.
size_t read_buffer_size_;
// Contains file descsriptor to which watched process output is written.
base::File process_output_file_;
std::unique_ptr<base::FileDescriptorWatcher::Controller> output_file_watcher_;
// Callback that will be invoked when some output is detected.
ProcessOutputCallback on_read_callback_;
// Count of unacked outputs sent.
int unacked_outputs_ = 0;
base::WeakPtrFactory<ProcessOutputWatcher> weak_factory_{this};
};
} // namespace chromeos
#endif // CHROMEOS_PROCESS_PROXY_PROCESS_OUTPUT_WATCHER_H_
|
