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
|
// Copyright 2006 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef COMPONENTS_SESSIONS_CORE_SESSION_COMMAND_H_
#define COMPONENTS_SESSIONS_CORE_SESSION_COMMAND_H_
#include <stddef.h>
#include <stdint.h>
#include <string>
#include <string_view>
#include "components/sessions/core/sessions_export.h"
namespace base {
class Pickle;
}
namespace sessions {
// SessionCommand contains a command id and arbitrary chunk of data. The id
// and chunk of data are specific to the service creating them.
//
// Both TabRestoreService and SessionService use SessionCommands to represent
// state on disk.
//
// There are two ways to create a SessionCommand:
// . Specify the size of the data block to create. This is useful for
// commands that have a fixed size.
// . From a pickle, this is useful for commands whose length varies.
class SESSIONS_EXPORT SessionCommand {
public:
// These get written to disk, so we define types for them.
// Type for the identifier.
using id_type = uint8_t;
// Type for writing the size.
using size_type = uint16_t;
// Creates a session command with the specified id. This allocates a buffer
// of size |size| that must be filled via contents().
SessionCommand(id_type id, size_type size);
// Convenience constructor that creates a session command with the specified
// id whose contents is populated from the contents of pickle.
SessionCommand(id_type id, const base::Pickle& pickle);
SessionCommand(const SessionCommand&) = delete;
SessionCommand& operator=(const SessionCommand&) = delete;
// The contents of the command.
char* contents() { return const_cast<char*>(contents_.c_str()); }
const char* contents() const { return contents_.c_str(); }
std::string_view contents_as_string_piece() const {
return std::string_view(contents_);
}
// Identifier for the command.
id_type id() const { return id_; }
// Size of data.
size_type size() const { return static_cast<size_type>(contents_.size()); }
// The serialized format has overhead (the serialized format includes the
// id). This returns the size to use when serializing.
size_type GetSerializedSize() const;
// Convenience for extracting the data to a target. Returns false if
// count is not equal to the size of data this command contains.
bool GetPayload(void* dest, size_t count) const;
// Returns the contents as a pickle.
base::Pickle PayloadAsPickle() const;
private:
const id_type id_;
std::string contents_;
};
} // namespace sessions
#endif // COMPONENTS_SESSIONS_CORE_SESSION_COMMAND_H_
|
