1 // mqueue.h - originally written and placed in the public domain by Wei Dai
2
3 /// \file
4 /// \brief Classes for an unlimited queue to store messages
5
6 #ifndef CRYPTOPP_MQUEUE_H
7 #define CRYPTOPP_MQUEUE_H
8
9 #include "cryptlib.h"
10 #include "queue.h"
11 #include "filters.h"
12 #include "misc.h"
13
14 #include <deque>
15
NAMESPACE_BEGIN(CryptoPP)16 NAMESPACE_BEGIN(CryptoPP)
17
18 /// \brief Data structure used to store messages
19 /// \details The queue is implemented with a ByteQueue.
20 /// \sa <A HREF="https://www.cryptopp.com/wiki/MessageQueue">MessageQueue</A>
21 /// on the Crypto++ wiki.
22 /// \since Crypto++ 2.0
23 class CRYPTOPP_DLL MessageQueue : public AutoSignaling<BufferedTransformation>
24 {
25 public:
26 virtual ~MessageQueue() {}
27
28 /// \brief Construct a MessageQueue
29 /// \param nodeSize the initial node size
30 MessageQueue(unsigned int nodeSize=256);
31
32 // BufferedTransformation
33 void IsolatedInitialize(const NameValuePairs ¶meters)
34 {m_queue.IsolatedInitialize(parameters); m_lengths.assign(1, 0U); m_messageCounts.assign(1, 0U);}
35 size_t Put2(const byte *begin, size_t length, int messageEnd, bool blocking)
36 {
37 CRYPTOPP_UNUSED(blocking);
38 m_queue.Put(begin, length);
39 m_lengths.back() += length;
40 if (messageEnd)
41 {
42 m_lengths.push_back(0);
43 m_messageCounts.back()++;
44 }
45 return 0;
46 }
47 bool IsolatedFlush(bool hardFlush, bool blocking)
48 {CRYPTOPP_UNUSED(hardFlush), CRYPTOPP_UNUSED(blocking); return false;}
49 bool IsolatedMessageSeriesEnd(bool blocking)
50 {CRYPTOPP_UNUSED(blocking); m_messageCounts.push_back(0); return false;}
51
52 lword MaxRetrievable() const
53 {return m_lengths.front();}
54 bool AnyRetrievable() const
55 {return m_lengths.front() > 0;}
56
57 size_t TransferTo2(BufferedTransformation &target, lword &transferBytes, const std::string &channel=DEFAULT_CHANNEL, bool blocking=true);
58 size_t CopyRangeTo2(BufferedTransformation &target, lword &begin, lword end=LWORD_MAX, const std::string &channel=DEFAULT_CHANNEL, bool blocking=true) const;
59
60 lword TotalBytesRetrievable() const
61 {return m_queue.MaxRetrievable();}
62 unsigned int NumberOfMessages() const
63 {return (unsigned int)m_lengths.size()-1;}
64 bool GetNextMessage();
65
66 unsigned int NumberOfMessagesInThisSeries() const
67 {return m_messageCounts[0];}
68 unsigned int NumberOfMessageSeries() const
69 {return (unsigned int)m_messageCounts.size()-1;}
70
71 /// \brief Copy messages from this object to another BufferedTransformation.
72 /// \param target the destination BufferedTransformation
73 /// \param count the number of messages to copy
74 /// \param channel the channel on which the transfer should occur
75 /// \return the number of messages that remain in the copy (i.e., messages not copied)
76 unsigned int CopyMessagesTo(BufferedTransformation &target, unsigned int count=UINT_MAX, const std::string &channel=DEFAULT_CHANNEL) const;
77
78 /// \brief Peek data in the queue
79 /// \param contiguousSize the size of the data
80 /// \details Spy() peeks at data at the head of the queue. Spy() does
81 /// not remove data from the queue.
82 /// \details The data's size is returned in <tt>contiguousSize</tt>.
83 /// Spy() returns the size of the first message in the list.
84 const byte * Spy(size_t &contiguousSize) const;
85
86 /// \brief Swap contents with another MessageQueue
87 /// \param rhs the other MessageQueue
88 void swap(MessageQueue &rhs);
89
90 private:
91 ByteQueue m_queue;
92 std::deque<lword> m_lengths;
93 std::deque<unsigned int> m_messageCounts;
94 };
95
96 /// \brief Filter that checks messages on two channels for equality
97 class CRYPTOPP_DLL EqualityComparisonFilter : public Unflushable<Multichannel<Filter> >
98 {
99 public:
100 /// \brief Different messages were detected
101 struct MismatchDetected : public Exception
102 {
103 /// \brief Construct a MismatchDetected exception
MismatchDetectedMismatchDetected104 MismatchDetected() : Exception(DATA_INTEGRITY_CHECK_FAILED, "EqualityComparisonFilter: did not receive the same data on two channels") {}
105 };
106
107 /// \brief Construct an EqualityComparisonFilter
108 /// \param attachment an attached transformation
109 /// \param throwIfNotEqual flag indicating whether the objects throws
110 /// \param firstChannel string naming the first channel
111 /// \param secondChannel string naming the second channel
112 /// \throw MismatchDetected if throwIfNotEqual is true and not equal
113 /// \details If throwIfNotEqual is false, this filter will output a '\\0'
114 /// byte when it detects a mismatch, '\\1' otherwise.
115 EqualityComparisonFilter(BufferedTransformation *attachment=NULLPTR, bool throwIfNotEqual=true, const std::string &firstChannel="0", const std::string &secondChannel="1")
m_throwIfNotEqual(throwIfNotEqual)116 : m_throwIfNotEqual(throwIfNotEqual), m_mismatchDetected(false)
117 , m_firstChannel(firstChannel), m_secondChannel(secondChannel)
118 {Detach(attachment);}
119
120 // BufferedTransformation
121 size_t ChannelPut2(const std::string &channel, const byte *begin, size_t length, int messageEnd, bool blocking);
122 bool ChannelMessageSeriesEnd(const std::string &channel, int propagation=-1, bool blocking=true);
123
124 protected:
125 unsigned int MapChannel(const std::string &channel) const;
126 bool HandleMismatchDetected(bool blocking);
127
128 private:
129 bool m_throwIfNotEqual, m_mismatchDetected;
130 std::string m_firstChannel, m_secondChannel;
131 MessageQueue m_q[2];
132 };
133
134 NAMESPACE_END
135
136 #ifndef __BORLANDC__
NAMESPACE_BEGIN(std)137 NAMESPACE_BEGIN(std)
138 template<> inline void swap(CryptoPP::MessageQueue &a, CryptoPP::MessageQueue &b)
139 {
140 a.swap(b);
141 }
142 NAMESPACE_END
143 #endif
144
145 #endif
146