1/*
2 * Copyright (c) 2000-2001,2003-2004,2006,2011,2014 Apple Inc. All Rights Reserved.
3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * This file contains Original Code and/or Modifications of Original Code
7 * as defined in and that are subject to the Apple Public Source License
8 * Version 2.0 (the 'License'). You may not use this file except in
9 * compliance with the License. Please obtain a copy of the License at
10 * http://www.opensource.apple.com/apsl/ and read it before using this
11 * file.
12 *
13 * The Original Code and all software distributed under the License are
14 * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
15 * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
16 * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
18 * Please see the License for the specific language governing rights and
19 * limitations under the License.
20 *
21 * @APPLE_LICENSE_HEADER_END@
22 */
23
24
25//
26// constdata - shared constant binary data objects
27//
28#ifndef _H_CONSTDATA
29#define _H_CONSTDATA
30
31#include <security_utilities/utilities.h>
32#include <security_utilities/refcount.h>
33
34
35namespace Security {
36
37
38//
39// ConstData represents a contiguous, binary blob of constant data.
40// Assignment is by sharing (thus cheap).
41// ConstData is a (constant) Dataoid type.
42//
43class ConstData {
44private:
45    class Blob : public RefCount {
46    public:
47        Blob() : mData(NULL), mSize(0) { }
48        Blob(const void *base, size_t size, bool takeOwnership = false);
49        ~Blob()		{ delete[] reinterpret_cast<const char *>(mData); }
50
51        const void *data() const	{ return mData; }
52        size_t length() const		{ return mSize; }
53
54    private:
55        const void *mData;
56        size_t mSize;
57    };
58
59public:
60    ConstData() { }		//@@@ use a nullBlob?
61    ConstData(const void *base, size_t size, bool takeOwnership = false)
62        : mBlob(new Blob(base, size, takeOwnership)) { }
63
64    template <class T>
65    static ConstData wrap(const T &obj, bool takeOwnership)
66    { return ConstData(&obj, sizeof(obj), takeOwnership); }
67
68public:
69    const void *data() const	{ return mBlob ? mBlob->data() : NULL; }
70    size_t length() const		{ return mBlob ? mBlob->length() : 0; }
71
72    operator bool() const		{ return mBlob; }
73    bool operator !() const		{ return !mBlob; }
74
75    template <class T> operator const T *() const
76    { return reinterpret_cast<const T *>(data()); }
77
78    template <class T> const T &as() const
79    { return *static_cast<const T *>(reinterpret_cast<const T *>(data())); }
80
81private:
82    RefPointer<Blob> mBlob;
83};
84
85
86}	// end namespace Security
87
88
89#endif //_H_CONSTDATA
90