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
|
#include "io.hh"
#include "../file.hh"
#include "chain.hh"
#include <cstddef>
namespace util {
namespace stream {
ReadSizeException::ReadSizeException() throw() {}
ReadSizeException::~ReadSizeException() throw() {}
void Read::Run(const ChainPosition &position) {
const std::size_t block_size = position.GetChain().BlockSize();
const std::size_t entry_size = position.GetChain().EntrySize();
for (Link link(position); link; ++link) {
std::size_t got = util::ReadOrEOF(file_, link->Get(), block_size);
UTIL_THROW_IF(got % entry_size, ReadSizeException, "File ended with " << got << " bytes, not a multiple of " << entry_size << ".");
if (got == 0) {
link.Poison();
return;
} else {
link->SetValidSize(got);
}
}
}
void PRead::Run(const ChainPosition &position) {
scoped_fd owner;
if (own_) owner.reset(file_);
const uint64_t size = SizeOrThrow(file_);
UTIL_THROW_IF(size % static_cast<uint64_t>(position.GetChain().EntrySize()), ReadSizeException, "File size " << file_ << " size is " << size << " not a multiple of " << position.GetChain().EntrySize());
const std::size_t block_size = position.GetChain().BlockSize();
const uint64_t block_size64 = static_cast<uint64_t>(block_size);
Link link(position);
uint64_t offset = 0;
for (; offset + block_size64 < size; offset += block_size64, ++link) {
ErsatzPRead(file_, link->Get(), block_size, offset);
link->SetValidSize(block_size);
}
// size - offset is <= block_size, so it casts to 32-bit fine.
if (size - offset) {
ErsatzPRead(file_, link->Get(), size - offset, offset);
link->SetValidSize(size - offset);
++link;
}
link.Poison();
}
void Write::Run(const ChainPosition &position) {
for (Link link(position); link; ++link) {
WriteOrThrow(file_, link->Get(), link->ValidSize());
}
}
void WriteAndRecycle::Run(const ChainPosition &position) {
const std::size_t block_size = position.GetChain().BlockSize();
for (Link link(position); link; ++link) {
WriteOrThrow(file_, link->Get(), link->ValidSize());
link->SetValidSize(block_size);
}
}
void PWrite::Run(const ChainPosition &position) {
uint64_t offset = 0;
for (Link link(position); link; ++link) {
ErsatzPWrite(file_, link->Get(), link->ValidSize(), offset);
offset += link->ValidSize();
}
// Trim file to size.
util::ResizeOrThrow(file_, offset);
}
} // namespace stream
} // namespace util
|
