summaryrefslogtreecommitdiff
path: root/plugins/Db3x_mmap/src/dbcache.cpp
blob: 62fcc1d0ca910f236d56e0390784bf5ec1468ae0 (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
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
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
/*

Miranda NG: the free IM client for Microsoft* Windows*

Copyright (c) 2012-17 Miranda NG project (https://miranda-ng.org)
all portions of this codebase are copyrighted to the people
listed in contributors.txt.

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
*/

#include "stdafx.h"

void CDb3Mmap::Map()
{
	DWORD dwProtectMode, dwAccess;
	if (cb && cb->bAggressive)
		dwProtectMode = PAGE_WRITECOPY, dwAccess = FILE_MAP_COPY;
	else if (m_bReadOnly)
		dwProtectMode = PAGE_READONLY, dwAccess = FILE_MAP_READ;
	else
		dwProtectMode = PAGE_READWRITE, dwAccess = FILE_MAP_ALL_ACCESS;

	m_hMap = CreateFileMapping(m_hDbFile, nullptr, dwProtectMode, 0, m_dwFileSize, nullptr);
	if (m_hMap) {
		m_pDbCache = (PBYTE)MapViewOfFile(m_hMap, dwAccess, 0, 0, 0);
		if (!m_pDbCache)
			DatabaseCorruption(L"%s (MapViewOfFile failed. Code: %d)");
	}
	else DatabaseCorruption(L"%s (CreateFileMapping failed. Code: %d)");
}

void CDb3Mmap::ReMap(DWORD needed)
{
	KillTimer(nullptr, m_flushBuffersTimerId);

	log3("remapping %d + %d (file end: %d)", m_dwFileSize, needed, m_dbHeader.ofsFileEnd);

	if (needed > 0) {
		if (needed > m_ChunkSize) {
			if (needed + m_dwFileSize > m_dbHeader.ofsFileEnd + m_ChunkSize)
				DatabaseCorruption(L"%s (Too large increment)");
			else {
				DWORD x = m_dbHeader.ofsFileEnd / m_ChunkSize;
				m_dwFileSize = (x + 1)*m_ChunkSize;
			}
		}
		else m_dwFileSize += m_ChunkSize;
	}

	UnmapViewOfFile(m_pDbCache);
	m_pDbCache = nullptr;
	CloseHandle(m_hMap);

	Map();
}

void CDb3Mmap::DBMoveChunk(DWORD ofsDest, DWORD ofsSource, int bytes)
{
	int x = 0;
	//log3("move %d %08x->%08x",bytes,ofsSource,ofsDest);
	if (ofsDest + bytes > m_dwFileSize)
		ReMap(ofsDest + bytes - m_dwFileSize);

	if (ofsSource + bytes > m_dwFileSize) {
		x = ofsSource + bytes - m_dwFileSize;
		log0("buggy move!");
	}
	if (x > 0)
		memset((m_pDbCache + ofsDest + bytes - x), 0, x);
	if (ofsSource < m_dwFileSize)
		memmove(m_pDbCache + ofsDest, m_pDbCache + ofsSource, bytes - x);

	logg();
}

//we are assumed to be in a mutex here
PBYTE CDb3Mmap::DBRead(DWORD ofs, int *bytesAvail)
{
	// buggy read
	if (ofs >= m_dwFileSize) {
		//log2("read from outside %d@%08x",bytesRequired,ofs);
		if (bytesAvail != nullptr)
			*bytesAvail = m_ChunkSize;
		return m_pNull;
	}
	//log3((ofs+bytesRequired > m_dwFileSize)?"read %d@%08x, only %d avaliable":"read %d@%08x",bytesRequired,ofs,m_dwFileSize-ofs);
	if (bytesAvail != nullptr)
		*bytesAvail = m_dwFileSize - ofs;
	return m_pDbCache + ofs;
}

//we are assumed to be in a mutex here
void CDb3Mmap::DBWrite(DWORD ofs, PVOID pData, int bytes)
{
	//log2("write %d@%08x",bytes,ofs);
	if (ofs + bytes > m_dwFileSize)
		ReMap(ofs + bytes - m_dwFileSize);
	memmove(m_pDbCache + ofs, pData, bytes);
	logg();
}

//we are assumed to be in a mutex here
void CDb3Mmap::DBFill(DWORD ofs, int bytes)
{
	//log2("zerofill %d@%08x",bytes,ofs);
	if ((ofs + bytes) <= m_dwFileSize)
		memset((m_pDbCache + ofs), 0, bytes);
	logg();
}

static VOID CALLBACK DoBufferFlushTimerProc(HWND, UINT, UINT_PTR idEvent, DWORD)
{
	for (int i = 0; i < g_Dbs.getCount(); i++) {
		CDb3Mmap *db = g_Dbs[i];
		if (db->m_flushBuffersTimerId != idEvent)
			continue;

		if (!db->m_pDbCache)
			return;

		KillTimer(nullptr, db->m_flushBuffersTimerId);
		log0("tflush1");
		if (FlushViewOfFile(db->m_pDbCache, 0) == 0) {
			if (db->m_flushFailTick == 0)
				db->m_flushFailTick = GetTickCount();
			else if (GetTickCount() - db->m_flushFailTick > 5000)
				db->DatabaseCorruption(nullptr);
		}
		else db->m_flushFailTick = 0;
		log0("tflush2");
	}
}

void CDb3Mmap::DBFlush(int setting)
{
	if (!setting) {
		log0("nflush1");
		if (m_safetyMode && m_pDbCache) {
			if (FlushViewOfFile(m_pDbCache, 0) == 0) {
				if (m_flushFailTick == 0)
					m_flushFailTick = GetTickCount();
				else if (GetTickCount() - m_flushFailTick > 5000)
					DatabaseCorruption(nullptr);
			}
			else m_flushFailTick = 0;
		}
		log0("nflush2");
		return;
	}
	KillTimer(nullptr, m_flushBuffersTimerId);
	m_flushBuffersTimerId = SetTimer(nullptr, m_flushBuffersTimerId, 50, DoBufferFlushTimerProc);
}

int CDb3Mmap::InitMap(void)
{
	m_dwFileSize = GetFileSize(m_hDbFile, nullptr);

	// Align to chunk
	if (!m_bReadOnly) {
		DWORD x = m_dwFileSize % m_ChunkSize;
		if (x)
			m_dwFileSize += m_ChunkSize - x;
	}

	Map();

	// zero region for reads outside the file
	m_pNull = (PBYTE)calloc(m_ChunkSize, 1);
	return 0;
}

DWORD CDb3Mmap::GetSettingsGroupOfsByModuleNameOfs(DBContact *dbc, DWORD ofsModuleName)
{
	DWORD ofsThis = dbc->ofsFirstSettings;
	while (ofsThis) {
		DBContactSettings *dbcs = (DBContactSettings*)DBRead(ofsThis, nullptr);
		if (dbcs->signature != DBCONTACTSETTINGS_SIGNATURE) DatabaseCorruption(nullptr);
		if (dbcs->ofsModuleName == ofsModuleName)
			return ofsThis;

		ofsThis = dbcs->ofsNext;
	}
	return 0;
}