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
198
199
200
201
202
|
// --------------------------------------------------------------------------
//
// File
// Name: RaidFileUtil.cpp
// Purpose: Utilities for raid files
// Created: 2003/07/11
//
// --------------------------------------------------------------------------
#include "Box.h"
#include <sys/types.h>
#include <sys/stat.h>
#include "RaidFileUtil.h"
#include "FileModificationTime.h"
#include "RaidFileRead.h" // for type definition
#include "MemLeakFindOn.h"
int64_t adjust_timestamp(int64_t timestamp, size_t file_size)
{
#ifndef BOX_RELEASE_BUILD
// Remove the microseconds part of the timestamp,
// to simulate filesystem with 1-second timestamp
// resolution, e.g. MacOS X HFS, old Linuxes.
// Otherwise it's easy to write tests that rely
// on more accurate timestamps, and pass on
// platforms that have them, and fail on others.
timestamp -= (timestamp % MICRO_SEC_IN_SEC);
#endif
// The resolution of timestamps may be very
// low, e.g. 1 second. So add the size to it
// to give a bit more chance of it changing.
// TODO: Make this better.
timestamp += file_size;
return timestamp;
}
// --------------------------------------------------------------------------
//
// Function
// Name: RaidFileUtil::RaidFileExists(RaidFileDiscSet &,
// const std::string &, int *, int *, int64_t *)
// Purpose: Check to see the state of a RaidFile on disc
// (doesn't look at contents, just at existence of
// files)
// Created: 2003/07/11
//
// --------------------------------------------------------------------------
RaidFileUtil::ExistType RaidFileUtil::RaidFileExists(RaidFileDiscSet &rDiscSet,
const std::string &rFilename, int *pStartDisc, int *pExistingFiles,
int64_t *pRevisionID)
{
if(pExistingFiles)
{
*pExistingFiles = 0;
}
EMU_STRUCT_STAT st;
// check various files
int startDisc = 0;
{
std::string writeFile(RaidFileUtil::MakeWriteFileName(rDiscSet, rFilename, &startDisc));
if(pStartDisc)
{
*pStartDisc = startDisc;
}
if(EMU_STAT(writeFile.c_str(), &st) == 0)
{
// write file exists, use that
// Get unique ID
if(pRevisionID != 0)
{
*pRevisionID = FileModificationTime(st);
*pRevisionID = adjust_timestamp(*pRevisionID, st.st_size);
}
// return non-raid file
return NonRaid;
}
}
// Now see how many of the raid components exist
int64_t revisionID = 0;
int setSize = rDiscSet.size();
int rfCount = 0;
// TODO: replace this with better linux revision ID detection
int64_t revisionIDplus = 0;
for(int f = 0; f < setSize; ++f)
{
std::string componentFile(RaidFileUtil::MakeRaidComponentName(rDiscSet, rFilename, (f + startDisc) % setSize));
if(EMU_STAT(componentFile.c_str(), &st) == 0)
{
// Component file exists, add to count
rfCount++;
// Set flags for existance?
if(pExistingFiles)
{
(*pExistingFiles) |= (1 << f);
}
// Revision ID
if(pRevisionID != 0)
{
int64_t rid = FileModificationTime(st);
if(rid > revisionID) revisionID = rid;
revisionIDplus += st.st_size;
}
}
}
if(pRevisionID != 0)
{
revisionID = adjust_timestamp(revisionID, revisionIDplus);
(*pRevisionID) = revisionID;
}
// Return a status based on how many parts are available
if(rfCount == setSize)
{
return AsRaid;
}
else if((setSize > 1) && rfCount == (setSize - 1))
{
return AsRaidWithMissingReadable;
}
else if(rfCount > 0)
{
return AsRaidWithMissingNotRecoverable;
}
return NoFile; // Obviously doesn't exist
}
// --------------------------------------------------------------------------
//
// Function
// Name: RaidFileUtil::DiscUsageInBlocks(int64_t, const RaidFileDiscSet &)
// Purpose: Returns the size of the file in blocks, given the file size and disc set
// Created: 2003/09/03
//
// --------------------------------------------------------------------------
int64_t RaidFileUtil::DiscUsageInBlocks(int64_t FileSize, const RaidFileDiscSet &rDiscSet)
{
// Get block size
int blockSize = rDiscSet.GetBlockSize();
// OK... so as the size of the file is always sizes of stripe1 + stripe2, we can
// do a very simple calculation for the main data.
int64_t blocks = (FileSize + (((int64_t)blockSize) - 1)) / ((int64_t)blockSize);
// It's just that simple calculation for non-RAID disc sets
if(rDiscSet.IsNonRaidSet())
{
return blocks;
}
// It's the parity which is mildly complex.
// First of all, add in size for all but the last two blocks.
int64_t parityblocks = (FileSize / ((int64_t)blockSize)) / 2;
blocks += parityblocks;
// Work out how many bytes are left
int bytesOver = (int)(FileSize - (parityblocks * ((int64_t)(blockSize*2))));
// Then... (let compiler optimise this out)
if(bytesOver == 0)
{
// Extra block for the size info
blocks++;
}
else if(bytesOver == sizeof(RaidFileRead::FileSizeType))
{
// For last block of parity, plus the size info
blocks += 2;
}
else if(bytesOver < blockSize)
{
// Just want the parity block
blocks += 1;
}
else if(bytesOver == blockSize || bytesOver >= ((blockSize*2)-((int)sizeof(RaidFileRead::FileSizeType))))
{
// Last block, plus size info
blocks += 2;
}
else
{
// Just want parity block
blocks += 1;
}
return blocks;
}
|
