Commit | Line | Data |
2c70efe1 |
1 | package DBM::Deep::Sector::File::Scalar; |
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2 | |
3 | use 5.006_000; |
4 | |
5 | use strict; |
6 | use warnings FATAL => 'all'; |
7 | |
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8 | use base qw( DBM::Deep::Sector::File::Data ); |
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9 | |
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10 | my $STALE_SIZE = 2; |
11 | |
12 | # Please refer to the pack() documentation for further information |
13 | my %StP = ( |
14 | 1 => 'C', # Unsigned char value (no order needed as it's just one byte) |
15 | 2 => 'n', # Unsigned short in "network" (big-endian) order |
16 | 4 => 'N', # Unsigned long in "network" (big-endian) order |
17 | 8 => 'Q', # Usigned quad (no order specified, presumably machine-dependent) |
18 | ); |
19 | |
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20 | sub free { |
21 | my $self = shift; |
22 | |
23 | my $chain_loc = $self->chain_loc; |
24 | |
25 | $self->SUPER::free(); |
26 | |
27 | if ( $chain_loc ) { |
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28 | $self->engine->load_sector( $chain_loc )->free; |
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29 | } |
30 | |
31 | return; |
32 | } |
33 | |
a4d36ff6 |
34 | sub clone { |
35 | my $self = shift; |
36 | return ref($self)->new({ |
37 | engine => $self->engine, |
38 | type => $self->type, |
39 | data => $self->data, |
40 | }); |
41 | } |
42 | |
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43 | sub type { $_[0]{engine}->SIG_DATA } |
44 | sub _init { |
45 | my $self = shift; |
46 | |
47 | my $engine = $self->engine; |
48 | |
49 | unless ( $self->offset ) { |
50 | my $data_section = $self->size - $self->base_size - $engine->byte_size - 1; |
51 | |
52 | $self->{offset} = $engine->_request_data_sector( $self->size ); |
53 | |
54 | my $data = delete $self->{data}; |
55 | my $dlen = length $data; |
56 | my $continue = 1; |
57 | my $curr_offset = $self->offset; |
58 | while ( $continue ) { |
59 | |
60 | my $next_offset = 0; |
61 | |
62 | my ($leftover, $this_len, $chunk); |
63 | if ( $dlen > $data_section ) { |
64 | $leftover = 0; |
65 | $this_len = $data_section; |
66 | $chunk = substr( $data, 0, $this_len ); |
67 | |
68 | $dlen -= $data_section; |
69 | $next_offset = $engine->_request_data_sector( $self->size ); |
70 | $data = substr( $data, $this_len ); |
71 | } |
72 | else { |
73 | $leftover = $data_section - $dlen; |
74 | $this_len = $dlen; |
75 | $chunk = $data; |
76 | |
77 | $continue = 0; |
78 | } |
79 | |
80 | $engine->storage->print_at( $curr_offset, $self->type ); # Sector type |
81 | # Skip staleness |
82 | $engine->storage->print_at( $curr_offset + $self->base_size, |
83 | pack( $StP{$engine->byte_size}, $next_offset ), # Chain loc |
84 | pack( $StP{1}, $this_len ), # Data length |
85 | $chunk, # Data to be stored in this sector |
86 | chr(0) x $leftover, # Zero-fill the rest |
87 | ); |
88 | |
89 | $curr_offset = $next_offset; |
90 | } |
91 | |
92 | return; |
93 | } |
94 | } |
95 | |
96 | sub data_length { |
97 | my $self = shift; |
98 | |
99 | my $buffer = $self->engine->storage->read_at( |
100 | $self->offset + $self->base_size + $self->engine->byte_size, 1 |
101 | ); |
102 | |
103 | return unpack( $StP{1}, $buffer ); |
104 | } |
105 | |
106 | sub chain_loc { |
107 | my $self = shift; |
108 | return unpack( |
109 | $StP{$self->engine->byte_size}, |
110 | $self->engine->storage->read_at( |
111 | $self->offset + $self->base_size, |
112 | $self->engine->byte_size, |
113 | ), |
114 | ); |
115 | } |
116 | |
117 | sub data { |
118 | my $self = shift; |
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119 | |
120 | my $data; |
121 | while ( 1 ) { |
122 | my $chain_loc = $self->chain_loc; |
123 | |
124 | $data .= $self->engine->storage->read_at( |
125 | $self->offset + $self->base_size + $self->engine->byte_size + 1, $self->data_length, |
126 | ); |
127 | |
128 | last unless $chain_loc; |
129 | |
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130 | $self = $self->engine->load_sector( $chain_loc ); |
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131 | } |
132 | |
133 | return $data; |
134 | } |
135 | |
136 | 1; |
137 | __END__ |