Blame view

cryptopp/mqueue.cpp 4.05 KB
Imanol-Mikel Barba Sabariego authored
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
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
// mqueue.cpp - written and placed in the public domain by Wei Dai

#include "pch.h"

#ifndef CRYPTOPP_IMPORTS

#include "mqueue.h"

NAMESPACE_BEGIN(CryptoPP)

MessageQueue::MessageQueue(unsigned int nodeSize)
	: m_queue(nodeSize), m_lengths(1, 0U), m_messageCounts(1, 0U)
{
}

size_t MessageQueue::CopyRangeTo2(BufferedTransformation &target, lword &begin, lword end, const std::string &channel, bool blocking) const
{
	if (begin >= MaxRetrievable())
		return 0;

	return m_queue.CopyRangeTo2(target, begin, STDMIN(MaxRetrievable(), end), channel, blocking);
}

size_t MessageQueue::TransferTo2(BufferedTransformation &target, lword &transferBytes, const std::string &channel, bool blocking)
{
	transferBytes = STDMIN(MaxRetrievable(), transferBytes);
	size_t blockedBytes = m_queue.TransferTo2(target, transferBytes, channel, blocking);
	m_lengths.front() -= transferBytes;
	return blockedBytes;
}

bool MessageQueue::GetNextMessage()
{
	if (NumberOfMessages() > 0 && !AnyRetrievable())
	{
		m_lengths.pop_front();
		if (m_messageCounts[0] == 0 && m_messageCounts.size() > 1)
			m_messageCounts.pop_front();
		return true;
	}
	else
		return false;
}

unsigned int MessageQueue::CopyMessagesTo(BufferedTransformation &target, unsigned int count, const std::string &channel) const
{
	ByteQueue::Walker walker(m_queue);
	std::deque<lword>::const_iterator it = m_lengths.begin();
	unsigned int i;
	for (i=0; i<count && it != --m_lengths.end(); ++i, ++it)
	{
		walker.TransferTo(target, *it, channel);
		if (GetAutoSignalPropagation())
			target.ChannelMessageEnd(channel, GetAutoSignalPropagation()-1);
	}
	return i;
}

void MessageQueue::swap(MessageQueue &rhs)
{
	m_queue.swap(rhs.m_queue);
	m_lengths.swap(rhs.m_lengths);
}

const byte * MessageQueue::Spy(size_t &contiguousSize) const
{
	const byte *result = m_queue.Spy(contiguousSize);
	contiguousSize = UnsignedMin(contiguousSize, MaxRetrievable());
	return result;
}

// *************************************************************

unsigned int EqualityComparisonFilter::MapChannel(const std::string &channel) const
{
	if (channel == m_firstChannel)
		return 0;
	else if (channel == m_secondChannel)
		return 1;
	else
		return 2;
}

size_t EqualityComparisonFilter::ChannelPut2(const std::string &channel, const byte *inString, size_t length, int messageEnd, bool blocking)
{
	if (!blocking)
		throw BlockingInputOnly("EqualityComparisonFilter");

	unsigned int i = MapChannel(channel);

	if (i == 2)
		return Output(3, inString, length, messageEnd, blocking, channel);
	else if (m_mismatchDetected)
		return 0;
	else
	{
		MessageQueue &q1 = m_q[i], &q2 = m_q[1-i];

		if (q2.AnyMessages() && q2.MaxRetrievable() < length)
			goto mismatch;

		while (length > 0 && q2.AnyRetrievable())
		{
			size_t len = length;
			const byte *data = q2.Spy(len);
			len = STDMIN(len, length);
			if (memcmp(inString, data, len) != 0)
				goto mismatch;
			inString += len;
			length -= len;
			q2.Skip(len);
		}

		q1.Put(inString, length);

		if (messageEnd)
		{
			if (q2.AnyRetrievable())
				goto mismatch;
			else if (q2.AnyMessages())
				q2.GetNextMessage();
			else if (q2.NumberOfMessageSeries() > 0)
				goto mismatch;
			else
				q1.MessageEnd();
		}

		return 0;

mismatch:
		return HandleMismatchDetected(blocking);
	}
}

bool EqualityComparisonFilter::ChannelMessageSeriesEnd(const std::string &channel, int propagation, bool blocking)
{
	unsigned int i = MapChannel(channel);

	if (i == 2)
	{
		OutputMessageSeriesEnd(4, propagation, blocking, channel);
		return false;
	}
	else if (m_mismatchDetected)
		return false;
	else
	{
		MessageQueue &q1 = m_q[i], &q2 = m_q[1-i];

		if (q2.AnyRetrievable() || q2.AnyMessages())
			goto mismatch;
		else if (q2.NumberOfMessageSeries() > 0)
			return Output(2, (const byte *)"\1", 1, 0, blocking) != 0;
		else
			q1.MessageSeriesEnd();

		return false;

mismatch:
		return HandleMismatchDetected(blocking);
	}
}

bool EqualityComparisonFilter::HandleMismatchDetected(bool blocking)
{
	m_mismatchDetected = true;
	if (m_throwIfNotEqual)
		throw MismatchDetected();
	return Output(1, (const byte *)"\0", 1, 0, blocking) != 0;
}

NAMESPACE_END

#endif