Commit | Line | Data |
460b1067 |
1 | package DBM::Deep::File; |
2 | |
3 | use 5.6.0; |
4 | |
5 | use strict; |
6 | use warnings; |
7 | |
8 | use Fcntl qw( :DEFAULT :flock :seek ); |
9 | |
10 | our $VERSION = '0.01'; |
11 | |
12 | sub new { |
13 | my $class = shift; |
14 | my ($args) = @_; |
15 | |
16 | my $self = bless { |
359a01ac |
17 | audit_fh => undef, |
18 | audit_file => undef, |
19 | autobless => 1, |
460b1067 |
20 | autoflush => undef, |
21 | end => 0, |
22 | fh => undef, |
23 | file => undef, |
24 | file_offset => 0, |
25 | locking => undef, |
26 | locked => 0, |
27 | filter_store_key => undef, |
28 | filter_store_value => undef, |
29 | filter_fetch_key => undef, |
30 | filter_fetch_value => undef, |
28394a1a |
31 | |
359a01ac |
32 | # These are values that are not expected to be passed in through |
33 | # $args. They are here for documentation purposes. |
34 | transaction_id => 0, |
35 | transaction_offset => 0, |
36 | base_db_obj => undef, |
460b1067 |
37 | }, $class; |
38 | |
39 | # Grab the parameters we want to use |
40 | foreach my $param ( keys %$self ) { |
41 | next unless exists $args->{$param}; |
42 | $self->{$param} = $args->{$param}; |
43 | } |
44 | |
45 | if ( $self->{fh} && !$self->{file_offset} ) { |
46 | $self->{file_offset} = tell( $self->{fh} ); |
47 | } |
48 | |
49 | $self->open unless $self->{fh}; |
50 | |
359a01ac |
51 | if ( $self->{audit_file} && !$self->{audit_fh} ) { |
52 | my $flags = O_WRONLY | O_APPEND | O_CREAT; |
53 | |
54 | my $fh; |
55 | sysopen( $fh, $self->{audit_file}, $flags ) |
56 | or die "Cannot open audit file '$self->{audit_file}' for read/write: $!"; |
57 | |
58 | # Set the audit_fh to autoflush |
59 | my $old = select $fh; |
60 | $|=1; |
61 | select $old; |
62 | |
63 | $self->{audit_fh} = $fh; |
64 | } |
65 | |
66 | |
460b1067 |
67 | return $self; |
68 | } |
69 | |
359a01ac |
70 | sub set_db { |
71 | unless ( $_[0]{base_db_obj} ) { |
72 | $_[0]{base_db_obj} = $_[1]; |
73 | Scalar::Util::weaken( $_[0]{base_db_obj} ); |
74 | } |
75 | } |
76 | |
460b1067 |
77 | sub open { |
78 | my $self = shift; |
79 | |
80 | # Adding O_BINARY does remove the need for the binmode below. However, |
81 | # I'm not going to remove it because I don't have the Win32 chops to be |
82 | # absolutely certain everything will be ok. |
83 | my $flags = O_RDWR | O_CREAT | O_BINARY; |
84 | |
85 | my $fh; |
86 | sysopen( $fh, $self->{file}, $flags ) |
87 | or die "DBM::Deep: Cannot sysopen file '$self->{file}': $!\n"; |
88 | $self->{fh} = $fh; |
89 | |
90 | # Even though we use O_BINARY, better be safe than sorry. |
91 | binmode $fh; |
92 | |
93 | if ($self->{autoflush}) { |
94 | my $old = select $fh; |
95 | $|=1; |
96 | select $old; |
97 | } |
98 | |
99 | return 1; |
100 | } |
101 | |
102 | sub close { |
103 | my $self = shift; |
104 | |
105 | if ( $self->{fh} ) { |
106 | close $self->{fh}; |
107 | $self->{fh} = undef; |
108 | } |
109 | |
110 | return 1; |
111 | } |
112 | |
019404df |
113 | sub print_at { |
114 | my $self = shift; |
115 | my $loc = shift; |
116 | |
117 | local ($/,$\); |
118 | |
119 | my $fh = $self->{fh}; |
120 | seek( $fh, $loc + $self->{file_offset}, SEEK_SET ); |
121 | print( $fh @_ ); |
122 | |
123 | return 1; |
124 | } |
125 | |
460b1067 |
126 | sub DESTROY { |
127 | my $self = shift; |
128 | return unless $self; |
129 | |
130 | $self->close; |
131 | |
132 | return; |
133 | } |
134 | |
019404df |
135 | sub request_space { |
136 | my $self = shift; |
137 | my ($size) = @_; |
138 | |
139 | my $loc = $self->{end}; |
140 | $self->{end} += $size; |
141 | |
142 | return $loc; |
143 | } |
144 | |
145 | #sub release_space { |
146 | # my $self = shift; |
147 | # my ($size, $loc) = @_; |
148 | # |
149 | # local($/,$\); |
150 | # |
151 | # my $next_loc = 0; |
152 | # |
153 | # my $fh = $self->{fh}; |
154 | # seek( $fh, $loc + $self->{file_offset}, SEEK_SET ); |
155 | # print( $fh SIG_FREE |
156 | # . pack($self->{long_pack}, $size ) |
157 | # . pack($self->{long_pack}, $next_loc ) |
158 | # ); |
159 | # |
160 | # return; |
161 | #} |
162 | |
15ba72cc |
163 | ## |
164 | # If db locking is set, flock() the db file. If called multiple |
165 | # times before unlock(), then the same number of unlocks() must |
166 | # be called before the lock is released. |
167 | ## |
168 | sub lock { |
169 | my $self = shift; |
170 | my ($obj, $type) = @_; |
171 | $type = LOCK_EX unless defined $type; |
172 | |
173 | if (!defined($self->{fh})) { return; } |
174 | |
175 | if ($self->{locking}) { |
176 | if (!$self->{locked}) { |
177 | flock($self->{fh}, $type); |
178 | |
179 | # refresh end counter in case file has changed size |
180 | my @stats = stat($self->{fh}); |
181 | $self->{end} = $stats[7]; |
182 | |
183 | # double-check file inode, in case another process |
184 | # has optimize()d our file while we were waiting. |
185 | if ($stats[1] != $self->{inode}) { |
186 | $self->close; |
187 | $self->open; |
188 | |
189 | #XXX This needs work |
190 | $obj->{engine}->setup_fh( $obj ); |
191 | |
192 | flock($self->{fh}, $type); # re-lock |
193 | |
194 | # This may not be necessary after re-opening |
195 | $self->{end} = (stat($self->{fh}))[7]; # re-end |
196 | } |
197 | } |
198 | $self->{locked}++; |
199 | |
200 | return 1; |
201 | } |
202 | |
203 | return; |
204 | } |
205 | |
206 | ## |
207 | # If db locking is set, unlock the db file. See note in lock() |
208 | # regarding calling lock() multiple times. |
209 | ## |
210 | sub unlock { |
211 | my $self = shift; |
212 | |
213 | if (!defined($self->{fh})) { return; } |
214 | |
215 | if ($self->{locking} && $self->{locked} > 0) { |
216 | $self->{locked}--; |
217 | if (!$self->{locked}) { flock($self->{fh}, LOCK_UN); } |
218 | |
219 | return 1; |
220 | } |
221 | |
222 | return; |
223 | } |
224 | |
225 | sub set_transaction_offset { |
226 | my $self = shift; |
227 | $self->{transaction_offset} = shift; |
228 | } |
229 | |
aa83bc1e |
230 | sub audit { |
231 | my $self = shift; |
232 | |
233 | if ( my $afh = $self->{audit_fh} ) { |
234 | my ($string) = @_; |
235 | |
236 | flock( $afh, LOCK_EX ); |
237 | |
238 | if ( $string =~ /^#/ ) { |
239 | print( $afh "$string " . localtime(time) . "\n" ); |
240 | } |
241 | else { |
242 | print( $afh "$string # " . localtime(time) . "\n" ); |
243 | } |
244 | |
245 | flock( $afh, LOCK_UN ); |
246 | } |
247 | |
248 | return 1; |
249 | } |
250 | |
28394a1a |
251 | sub begin_transaction { |
252 | my $self = shift; |
253 | |
15ba72cc |
254 | my $fh = $self->{fh}; |
255 | |
20b7f047 |
256 | $self->lock; |
257 | |
aa83bc1e |
258 | seek( $fh, $self->{transaction_offset} + $self->{file_offset}, SEEK_SET ); |
20b7f047 |
259 | my $buffer; |
260 | read( $fh, $buffer, 4 ); |
261 | $buffer = unpack( 'N', $buffer ); |
262 | |
263 | for ( 1 .. 32 ) { |
264 | next if $buffer & (1 << ($_ - 1)); |
265 | $self->{transaction_id} = $_; |
c9b6d0d8 |
266 | $buffer |= (1 << $_-1 ); |
20b7f047 |
267 | last; |
268 | } |
269 | |
aa83bc1e |
270 | seek( $fh, $self->{transaction_offset} + $self->{file_offset}, SEEK_SET ); |
20b7f047 |
271 | print( $fh pack( 'N', $buffer ) ); |
15ba72cc |
272 | |
20b7f047 |
273 | $self->unlock; |
274 | |
275 | return $self->{transaction_id}; |
28394a1a |
276 | } |
277 | |
278 | sub end_transaction { |
279 | my $self = shift; |
280 | |
20b7f047 |
281 | my $fh = $self->{fh}; |
282 | |
283 | $self->lock; |
284 | |
aa83bc1e |
285 | seek( $fh, $self->{transaction_offset} + $self->{file_offset}, SEEK_SET ); |
20b7f047 |
286 | my $buffer; |
287 | read( $fh, $buffer, 4 ); |
288 | $buffer = unpack( 'N', $buffer ); |
289 | |
290 | # Unset $self->{transaction_id} bit |
291 | |
aa83bc1e |
292 | seek( $fh, $self->{transaction_offset} + $self->{file_offset}, SEEK_SET ); |
20b7f047 |
293 | print( $fh pack( 'N', $buffer ) ); |
294 | |
295 | $self->unlock; |
15ba72cc |
296 | |
28394a1a |
297 | $self->{transaction_id} = 0; |
298 | } |
299 | |
20b7f047 |
300 | sub current_transactions { |
28394a1a |
301 | my $self = shift; |
302 | |
20b7f047 |
303 | my $fh = $self->{fh}; |
304 | |
305 | $self->lock; |
306 | |
aa83bc1e |
307 | seek( $fh, $self->{transaction_offset} + $self->{file_offset}, SEEK_SET ); |
20b7f047 |
308 | my $buffer; |
309 | read( $fh, $buffer, 4 ); |
310 | $buffer = unpack( 'N', $buffer ); |
311 | |
312 | $self->unlock; |
313 | |
314 | my @transactions; |
315 | for ( 1 .. 32 ) { |
316 | if ( $buffer & (1 << ($_ - 1)) ) { |
317 | push @transactions, $_; |
318 | } |
319 | } |
320 | |
c9b6d0d8 |
321 | return grep { $_ != $self->{transaction_id} } @transactions; |
28394a1a |
322 | } |
323 | |
20b7f047 |
324 | sub transaction_id { return $_[0]->{transaction_id} } |
325 | |
28394a1a |
326 | #sub commit { |
327 | #} |
328 | |
460b1067 |
329 | 1; |
330 | __END__ |
331 | |