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