blob: eae7984abff5515fc4e3ff7ec098a2811d7d802d (
plain)
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 (c) 2009 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#ifndef BASE_REF_COUNTED_MEMORY_H_
#define BASE_REF_COUNTED_MEMORY_H_
#include <vector>
#include "base/ref_counted.h"
// TODO(erg): The contents of this file should be in a namespace. This would
// require touching >100 files in chrome/ though.
// A generic interface to memory. This object is reference counted because one
// of its two subclasses own the data they carry, and we need to have
// heterogeneous containers of these two types of memory.
class RefCountedMemory : public base::RefCountedThreadSafe<RefCountedMemory> {
public:
// Retrieves a pointer to the beginning of the data we point to. If the data
// is empty, this will return NULL.
virtual const unsigned char* front() const = 0;
// Size of the memory pointed to.
virtual size_t size() const = 0;
protected:
friend class base::RefCountedThreadSafe<RefCountedMemory>;
virtual ~RefCountedMemory() {}
};
// An implementation of RefCountedMemory, where the ref counting does not
// matter.
class RefCountedStaticMemory : public RefCountedMemory {
public:
RefCountedStaticMemory()
: data_(NULL), length_(0) {}
RefCountedStaticMemory(const unsigned char* data, size_t length)
: data_(data), length_(length) {}
virtual const unsigned char* front() const { return data_; }
virtual size_t size() const { return length_; }
private:
const unsigned char* data_;
size_t length_;
DISALLOW_COPY_AND_ASSIGN(RefCountedStaticMemory);
};
// An implementation of RefCountedMemory, where we own our the data in a
// vector.
class RefCountedBytes : public RefCountedMemory {
public:
// Constructs a RefCountedBytes object by performing a swap. (To non
// destructively build a RefCountedBytes, use the constructor that takes a
// vector.)
static RefCountedBytes* TakeVector(std::vector<unsigned char>* to_destroy) {
RefCountedBytes* bytes = new RefCountedBytes;
bytes->data.swap(*to_destroy);
return bytes;
}
RefCountedBytes() {}
// Constructs a RefCountedBytes object by _copying_ from |initializer|.
RefCountedBytes(const std::vector<unsigned char>& initializer)
: data(initializer) {}
virtual const unsigned char* front() const {
// STL will assert if we do front() on an empty vector, but calling code
// expects a NULL.
return size() ? &data.front() : NULL;
}
virtual size_t size() const { return data.size(); }
std::vector<unsigned char> data;
private:
DISALLOW_COPY_AND_ASSIGN(RefCountedBytes);
};
#endif // BASE_REF_COUNTED_MEMORY_H_
|
