Commit | Line | Data |
2c70efe1 |
1 | package DBM::Deep::Sector::File::Scalar; |
f0276afb |
2 | |
3 | use 5.006_000; |
4 | |
5 | use strict; |
6 | use warnings FATAL => 'all'; |
616df1be |
7 | no warnings 'recursion'; |
f0276afb |
8 | |
2c70efe1 |
9 | use base qw( DBM::Deep::Sector::File::Data ); |
f0276afb |
10 | |
5ae752e2 |
11 | my $STALE_SIZE = 2; |
12 | |
13 | # Please refer to the pack() documentation for further information |
14 | my %StP = ( |
15 | 1 => 'C', # Unsigned char value (no order needed as it's just one byte) |
16 | 2 => 'n', # Unsigned short in "network" (big-endian) order |
17 | 4 => 'N', # Unsigned long in "network" (big-endian) order |
18 | 8 => 'Q', # Usigned quad (no order specified, presumably machine-dependent) |
19 | ); |
20 | |
f0276afb |
21 | sub free { |
22 | my $self = shift; |
23 | |
24 | my $chain_loc = $self->chain_loc; |
25 | |
26 | $self->SUPER::free(); |
27 | |
28 | if ( $chain_loc ) { |
d6ecf579 |
29 | $self->engine->load_sector( $chain_loc )->free; |
f0276afb |
30 | } |
31 | |
32 | return; |
33 | } |
34 | |
35 | sub type { $_[0]{engine}->SIG_DATA } |
36 | sub _init { |
37 | my $self = shift; |
38 | |
39 | my $engine = $self->engine; |
40 | |
41 | unless ( $self->offset ) { |
42 | my $data_section = $self->size - $self->base_size - $engine->byte_size - 1; |
43 | |
44 | $self->{offset} = $engine->_request_data_sector( $self->size ); |
45 | |
46 | my $data = delete $self->{data}; |
47 | my $dlen = length $data; |
48 | my $continue = 1; |
49 | my $curr_offset = $self->offset; |
50 | while ( $continue ) { |
51 | |
52 | my $next_offset = 0; |
53 | |
54 | my ($leftover, $this_len, $chunk); |
55 | if ( $dlen > $data_section ) { |
56 | $leftover = 0; |
57 | $this_len = $data_section; |
58 | $chunk = substr( $data, 0, $this_len ); |
59 | |
60 | $dlen -= $data_section; |
61 | $next_offset = $engine->_request_data_sector( $self->size ); |
62 | $data = substr( $data, $this_len ); |
63 | } |
64 | else { |
65 | $leftover = $data_section - $dlen; |
66 | $this_len = $dlen; |
67 | $chunk = $data; |
68 | |
69 | $continue = 0; |
70 | } |
71 | |
72 | $engine->storage->print_at( $curr_offset, $self->type ); # Sector type |
73 | # Skip staleness |
74 | $engine->storage->print_at( $curr_offset + $self->base_size, |
75 | pack( $StP{$engine->byte_size}, $next_offset ), # Chain loc |
76 | pack( $StP{1}, $this_len ), # Data length |
77 | $chunk, # Data to be stored in this sector |
78 | chr(0) x $leftover, # Zero-fill the rest |
79 | ); |
80 | |
81 | $curr_offset = $next_offset; |
82 | } |
83 | |
84 | return; |
85 | } |
86 | } |
87 | |
88 | sub data_length { |
89 | my $self = shift; |
90 | |
91 | my $buffer = $self->engine->storage->read_at( |
92 | $self->offset + $self->base_size + $self->engine->byte_size, 1 |
93 | ); |
94 | |
95 | return unpack( $StP{1}, $buffer ); |
96 | } |
97 | |
98 | sub chain_loc { |
99 | my $self = shift; |
100 | return unpack( |
101 | $StP{$self->engine->byte_size}, |
102 | $self->engine->storage->read_at( |
103 | $self->offset + $self->base_size, |
104 | $self->engine->byte_size, |
105 | ), |
106 | ); |
107 | } |
108 | |
109 | sub data { |
110 | my $self = shift; |
f0276afb |
111 | |
112 | my $data; |
113 | while ( 1 ) { |
114 | my $chain_loc = $self->chain_loc; |
115 | |
116 | $data .= $self->engine->storage->read_at( |
117 | $self->offset + $self->base_size + $self->engine->byte_size + 1, $self->data_length, |
118 | ); |
119 | |
120 | last unless $chain_loc; |
121 | |
d6ecf579 |
122 | $self = $self->engine->load_sector( $chain_loc ); |
f0276afb |
123 | } |
124 | |
125 | return $data; |
126 | } |
127 | |
128 | 1; |
129 | __END__ |