Commit | Line | Data |
2c70efe1 |
1 | package DBM::Deep::Engine::DBI; |
2 | |
3 | use 5.006_000; |
4 | |
5 | use strict; |
6 | use warnings FATAL => 'all'; |
7 | |
8 | use base 'DBM::Deep::Engine'; |
9 | |
d6ecf579 |
10 | use DBM::Deep::Sector::DBI (); |
11 | use DBM::Deep::Storage::DBI (); |
12 | |
13 | sub sector_type { 'DBM::Deep::Sector::DBI' } |
19b913ce |
14 | sub iterator_class { 'DBM::Deep::Iterator::DBI' } |
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15 | |
a4d36ff6 |
16 | sub new { |
17 | my $class = shift; |
18 | my ($args) = @_; |
19 | |
20 | $args->{storage} = DBM::Deep::Storage::DBI->new( $args ) |
21 | unless exists $args->{storage}; |
22 | |
23 | my $self = bless { |
24 | storage => undef, |
25 | }, $class; |
26 | |
27 | # Grab the parameters we want to use |
28 | foreach my $param ( keys %$self ) { |
29 | next unless exists $args->{$param}; |
30 | $self->{$param} = $args->{$param}; |
31 | } |
32 | |
33 | return $self; |
34 | } |
35 | |
36 | sub setup { |
37 | my $self = shift; |
38 | my ($obj) = @_; |
39 | |
40 | # Default the id to 1. This means that we will be creating a row if there |
41 | # isn't one. The assumption is that the row_id=1 cannot never be deleted. I |
42 | # don't know if this is a good assumption. |
43 | $obj->{base_offset} ||= 1; |
44 | |
45 | my ($rows) = $self->storage->read_from( |
46 | refs => $obj->_base_offset, |
47 | qw( ref_type ), |
48 | ); |
49 | |
50 | # We don't have a row yet. |
51 | unless ( @$rows ) { |
52 | $self->storage->write_to( |
53 | refs => $obj->_base_offset, |
54 | ref_type => $obj->_type, |
55 | ); |
56 | } |
57 | |
58 | my $sector = DBM::Deep::Sector::DBI::Reference->new({ |
59 | engine => $self, |
60 | offset => $obj->_base_offset, |
61 | }); |
62 | } |
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63 | |
2c70efe1 |
64 | sub read_value { |
65 | my $self = shift; |
66 | my ($obj, $key) = @_; |
a4d36ff6 |
67 | |
68 | my $sector = $self->load_sector( $obj->_base_offset, 'refs' ) |
69 | or return; |
70 | |
71 | # if ( $sector->staleness != $obj->_staleness ) { |
72 | # return; |
73 | # } |
74 | |
75 | # my $key_md5 = $self->_apply_digest( $key ); |
76 | |
77 | my $value_sector = $sector->get_data_for({ |
78 | key => $key, |
79 | # key_md5 => $key_md5, |
80 | allow_head => 1, |
81 | }); |
82 | |
83 | unless ( $value_sector ) { |
84 | $value_sector = DBM::Deep::Sector::DBI::Scalar->new({ |
85 | engine => $self, |
86 | data => undef, |
87 | }); |
88 | |
89 | $sector->write_data({ |
90 | # key_md5 => $key_md5, |
91 | key => $key, |
92 | value => $value_sector, |
93 | }); |
94 | } |
95 | |
96 | return $value_sector->data; |
2c70efe1 |
97 | } |
98 | |
a4d36ff6 |
99 | =pod |
2c70efe1 |
100 | sub get_classname { |
101 | my $self = shift; |
102 | my ($obj) = @_; |
103 | } |
104 | |
105 | sub make_reference { |
106 | my $self = shift; |
107 | my ($obj, $old_key, $new_key) = @_; |
108 | } |
a4d36ff6 |
109 | =cut |
2c70efe1 |
110 | |
a4d36ff6 |
111 | # exists returns '', not undefined. |
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112 | sub key_exists { |
113 | my $self = shift; |
114 | my ($obj, $key) = @_; |
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115 | |
116 | my $sector = $self->load_sector( $obj->_base_offset, 'refs' ) |
117 | or return ''; |
118 | |
119 | # if ( $sector->staleness != $obj->_staleness ) { |
120 | # return ''; |
121 | # } |
122 | |
123 | my $data = $sector->get_data_for({ |
124 | # key_md5 => $self->_apply_digest( $key ), |
125 | key => $key, |
126 | allow_head => 1, |
127 | }); |
128 | |
129 | # exists() returns 1 or '' for true/false. |
130 | return $data ? 1 : ''; |
2c70efe1 |
131 | } |
132 | |
133 | sub delete_key { |
134 | my $self = shift; |
135 | my ($obj, $key) = @_; |
a4d36ff6 |
136 | |
137 | my $sector = $self->load_sector( $obj->_base_offset, 'refs' ) |
138 | or return ''; |
139 | |
140 | # if ( $sector->staleness != $obj->_staleness ) { |
141 | # return ''; |
142 | # } |
143 | |
144 | return $sector->delete_key({ |
145 | # key_md5 => $self->_apply_digest( $key ), |
146 | key => $key, |
147 | allow_head => 0, |
148 | }); |
2c70efe1 |
149 | } |
150 | |
151 | sub write_value { |
152 | my $self = shift; |
153 | my ($obj, $key, $value) = @_; |
154 | |
155 | my $r = Scalar::Util::reftype( $value ) || ''; |
156 | { |
157 | last if $r eq ''; |
158 | last if $r eq 'HASH'; |
159 | last if $r eq 'ARRAY'; |
160 | |
161 | DBM::Deep->_throw_error( |
162 | "Storage of references of type '$r' is not supported." |
163 | ); |
164 | } |
165 | |
166 | # Load the reference entry |
167 | # Determine if the row was deleted under us |
168 | # |
169 | |
a4d36ff6 |
170 | my $sector = $self->load_sector( $obj->_base_offset, 'refs' ) |
171 | or die "Cannot load sector at '@{[$obj->_base_offset]}'\n";; |
172 | |
173 | my ($type, $class); |
2c70efe1 |
174 | if ( $r eq 'ARRAY' || $r eq 'HASH' ) { |
175 | my $tmpvar; |
176 | if ( $r eq 'ARRAY' ) { |
177 | $tmpvar = tied @$value; |
178 | } elsif ( $r eq 'HASH' ) { |
179 | $tmpvar = tied %$value; |
180 | } |
181 | |
182 | if ( $tmpvar ) { |
183 | my $is_dbm_deep = eval { local $SIG{'__DIE__'}; $tmpvar->isa( 'DBM::Deep' ); }; |
184 | |
185 | unless ( $is_dbm_deep ) { |
186 | DBM::Deep->_throw_error( "Cannot store something that is tied." ); |
187 | } |
188 | |
189 | unless ( $tmpvar->_engine->storage == $self->storage ) { |
190 | DBM::Deep->_throw_error( "Cannot store values across DBM::Deep files. Please use export() instead." ); |
191 | } |
192 | |
193 | # Load $tmpvar's sector |
194 | |
195 | # First, verify if we're storing the same thing to this spot. If we |
196 | # are, then this should be a no-op. -EJS, 2008-05-19 |
197 | |
198 | # See whether or not we are storing ourselves to ourself. |
199 | # Write the sector as data in this reference (keyed by $key) |
a4d36ff6 |
200 | my $value_sector = $self->load_sector( $tmpvar->_base_offset ); |
201 | $sector->write_data({ |
202 | key => $key, |
203 | key_md5 => $self->_apply_digest( $key ), |
204 | value => $value_sector, |
205 | }); |
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206 | $value_sector->increment_refcount; |
207 | |
208 | return 1; |
209 | } |
210 | |
211 | $type = substr( $r, 0, 1 ); |
a4d36ff6 |
212 | $class = 'DBM::Deep::Sector::DBI::Reference'; |
2c70efe1 |
213 | } |
214 | else { |
215 | if ( tied($value) ) { |
216 | DBM::Deep->_throw_error( "Cannot store something that is tied." ); |
217 | } |
a4d36ff6 |
218 | |
219 | $class = 'DBM::Deep::Sector::DBI::Scalar'; |
220 | $type = 'S'; |
2c70efe1 |
221 | } |
222 | |
a4d36ff6 |
223 | # Create this after loading the reference sector in case something bad |
224 | # happens. This way, we won't allocate value sector(s) needlessly. |
225 | my $value_sector = $class->new({ |
226 | engine => $self, |
227 | data => $value, |
228 | type => $type, |
229 | }); |
230 | |
231 | $sector->write_data({ |
232 | key => $key, |
233 | # key_md5 => $self->_apply_digest( $key ), |
234 | value => $value_sector, |
235 | }); |
236 | |
2c70efe1 |
237 | # This code is to make sure we write all the values in the $value to the |
238 | # disk and to make sure all changes to $value after the assignment are |
239 | # reflected on disk. This may be counter-intuitive at first, but it is |
240 | # correct dwimmery. |
241 | # NOTE - simply tying $value won't perform a STORE on each value. Hence, |
242 | # the copy to a temp value. |
243 | if ( $r eq 'ARRAY' ) { |
244 | my @temp = @$value; |
245 | tie @$value, 'DBM::Deep', { |
246 | base_offset => $value_sector->offset, |
a4d36ff6 |
247 | # staleness => $value_sector->staleness, |
2c70efe1 |
248 | storage => $self->storage, |
249 | engine => $self, |
250 | }; |
251 | @$value = @temp; |
252 | bless $value, 'DBM::Deep::Array' unless Scalar::Util::blessed( $value ); |
253 | } |
254 | elsif ( $r eq 'HASH' ) { |
255 | my %temp = %$value; |
256 | tie %$value, 'DBM::Deep', { |
257 | base_offset => $value_sector->offset, |
a4d36ff6 |
258 | # staleness => $value_sector->staleness, |
2c70efe1 |
259 | storage => $self->storage, |
260 | engine => $self, |
261 | }; |
262 | |
263 | %$value = %temp; |
264 | bless $value, 'DBM::Deep::Hash' unless Scalar::Util::blessed( $value ); |
265 | } |
266 | |
267 | return 1; |
268 | } |
269 | |
2c70efe1 |
270 | sub begin_work { |
271 | my $self = shift; |
272 | my ($obj) = @_; |
273 | } |
274 | |
275 | sub rollback { |
276 | my $self = shift; |
277 | my ($obj) = @_; |
278 | } |
279 | |
280 | sub commit { |
281 | my $self = shift; |
282 | my ($obj) = @_; |
283 | } |
284 | |
285 | |
286 | 1; |
287 | __END__ |