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, |
25c7c8d6 |
36 | trans_audit => undef, |
359a01ac |
37 | base_db_obj => undef, |
460b1067 |
38 | }, $class; |
39 | |
40 | # Grab the parameters we want to use |
41 | foreach my $param ( keys %$self ) { |
42 | next unless exists $args->{$param}; |
43 | $self->{$param} = $args->{$param}; |
44 | } |
45 | |
46 | if ( $self->{fh} && !$self->{file_offset} ) { |
47 | $self->{file_offset} = tell( $self->{fh} ); |
48 | } |
49 | |
50 | $self->open unless $self->{fh}; |
51 | |
359a01ac |
52 | if ( $self->{audit_file} && !$self->{audit_fh} ) { |
53 | my $flags = O_WRONLY | O_APPEND | O_CREAT; |
54 | |
55 | my $fh; |
56 | sysopen( $fh, $self->{audit_file}, $flags ) |
57 | or die "Cannot open audit file '$self->{audit_file}' for read/write: $!"; |
58 | |
59 | # Set the audit_fh to autoflush |
60 | my $old = select $fh; |
61 | $|=1; |
62 | select $old; |
63 | |
64 | $self->{audit_fh} = $fh; |
65 | } |
66 | |
67 | |
460b1067 |
68 | return $self; |
69 | } |
70 | |
359a01ac |
71 | sub set_db { |
25c7c8d6 |
72 | my $self = shift; |
73 | unless ( $self->{base_db_obj} ) { |
74 | $self->{base_db_obj} = shift; |
75 | Scalar::Util::weaken( $self->{base_db_obj} ); |
359a01ac |
76 | } |
25c7c8d6 |
77 | |
78 | return; |
359a01ac |
79 | } |
80 | |
460b1067 |
81 | sub open { |
82 | my $self = shift; |
83 | |
84 | # Adding O_BINARY does remove the need for the binmode below. However, |
85 | # I'm not going to remove it because I don't have the Win32 chops to be |
86 | # absolutely certain everything will be ok. |
87 | my $flags = O_RDWR | O_CREAT | O_BINARY; |
88 | |
89 | my $fh; |
90 | sysopen( $fh, $self->{file}, $flags ) |
91 | or die "DBM::Deep: Cannot sysopen file '$self->{file}': $!\n"; |
92 | $self->{fh} = $fh; |
93 | |
94 | # Even though we use O_BINARY, better be safe than sorry. |
95 | binmode $fh; |
96 | |
97 | if ($self->{autoflush}) { |
98 | my $old = select $fh; |
99 | $|=1; |
100 | select $old; |
101 | } |
102 | |
103 | return 1; |
104 | } |
105 | |
106 | sub close { |
107 | my $self = shift; |
108 | |
109 | if ( $self->{fh} ) { |
110 | close $self->{fh}; |
111 | $self->{fh} = undef; |
112 | } |
113 | |
114 | return 1; |
115 | } |
116 | |
7dcefff3 |
117 | sub set_inode { |
118 | my $self = shift; |
119 | |
120 | unless ( $self->{inode} ) { |
121 | my @stats = stat($self->{fh}); |
122 | $self->{inode} = $stats[1]; |
123 | $self->{end} = $stats[7]; |
124 | } |
125 | |
126 | return 1; |
127 | } |
128 | |
019404df |
129 | sub print_at { |
130 | my $self = shift; |
131 | my $loc = shift; |
132 | |
133 | local ($/,$\); |
134 | |
135 | my $fh = $self->{fh}; |
7dcefff3 |
136 | if ( defined $loc ) { |
137 | seek( $fh, $loc + $self->{file_offset}, SEEK_SET ); |
138 | } |
139 | |
019404df |
140 | print( $fh @_ ); |
141 | |
142 | return 1; |
143 | } |
144 | |
7dcefff3 |
145 | sub read_at { |
146 | my $self = shift; |
147 | my ($loc, $size) = @_; |
148 | |
149 | local ($/,$\); |
150 | |
151 | my $fh = $self->{fh}; |
152 | if ( defined $loc ) { |
153 | seek( $fh, $loc + $self->{file_offset}, SEEK_SET ); |
154 | } |
155 | |
156 | my $buffer; |
157 | read( $fh, $buffer, $size); |
158 | |
159 | return $buffer; |
160 | } |
161 | |
162 | sub increment_pointer { |
163 | my $self = shift; |
164 | my ($size) = @_; |
165 | |
166 | if ( defined $size ) { |
167 | seek( $self->{fh}, $size, SEEK_CUR ); |
168 | } |
169 | |
170 | return 1; |
171 | } |
172 | |
460b1067 |
173 | sub DESTROY { |
174 | my $self = shift; |
175 | return unless $self; |
176 | |
177 | $self->close; |
178 | |
179 | return; |
180 | } |
181 | |
019404df |
182 | sub request_space { |
183 | my $self = shift; |
184 | my ($size) = @_; |
185 | |
7dcefff3 |
186 | #XXX Do I need to reset $self->{end} here? I need a testcase |
019404df |
187 | my $loc = $self->{end}; |
188 | $self->{end} += $size; |
189 | |
190 | return $loc; |
191 | } |
192 | |
193 | #sub release_space { |
194 | # my $self = shift; |
195 | # my ($size, $loc) = @_; |
196 | # |
197 | # local($/,$\); |
198 | # |
199 | # my $next_loc = 0; |
200 | # |
201 | # my $fh = $self->{fh}; |
202 | # seek( $fh, $loc + $self->{file_offset}, SEEK_SET ); |
203 | # print( $fh SIG_FREE |
204 | # . pack($self->{long_pack}, $size ) |
205 | # . pack($self->{long_pack}, $next_loc ) |
206 | # ); |
207 | # |
208 | # return; |
209 | #} |
210 | |
15ba72cc |
211 | ## |
212 | # If db locking is set, flock() the db file. If called multiple |
213 | # times before unlock(), then the same number of unlocks() must |
214 | # be called before the lock is released. |
215 | ## |
216 | sub lock { |
217 | my $self = shift; |
218 | my ($obj, $type) = @_; |
219 | $type = LOCK_EX unless defined $type; |
220 | |
221 | if (!defined($self->{fh})) { return; } |
222 | |
223 | if ($self->{locking}) { |
224 | if (!$self->{locked}) { |
225 | flock($self->{fh}, $type); |
226 | |
227 | # refresh end counter in case file has changed size |
228 | my @stats = stat($self->{fh}); |
229 | $self->{end} = $stats[7]; |
230 | |
231 | # double-check file inode, in case another process |
232 | # has optimize()d our file while we were waiting. |
233 | if ($stats[1] != $self->{inode}) { |
234 | $self->close; |
235 | $self->open; |
236 | |
237 | #XXX This needs work |
238 | $obj->{engine}->setup_fh( $obj ); |
239 | |
240 | flock($self->{fh}, $type); # re-lock |
241 | |
242 | # This may not be necessary after re-opening |
243 | $self->{end} = (stat($self->{fh}))[7]; # re-end |
244 | } |
245 | } |
246 | $self->{locked}++; |
247 | |
248 | return 1; |
249 | } |
250 | |
251 | return; |
252 | } |
253 | |
254 | ## |
255 | # If db locking is set, unlock the db file. See note in lock() |
256 | # regarding calling lock() multiple times. |
257 | ## |
258 | sub unlock { |
259 | my $self = shift; |
260 | |
261 | if (!defined($self->{fh})) { return; } |
262 | |
263 | if ($self->{locking} && $self->{locked} > 0) { |
264 | $self->{locked}--; |
265 | if (!$self->{locked}) { flock($self->{fh}, LOCK_UN); } |
266 | |
267 | return 1; |
268 | } |
269 | |
270 | return; |
271 | } |
272 | |
273 | sub set_transaction_offset { |
274 | my $self = shift; |
275 | $self->{transaction_offset} = shift; |
276 | } |
277 | |
aa83bc1e |
278 | sub audit { |
279 | my $self = shift; |
25c7c8d6 |
280 | my ($string) = @_; |
aa83bc1e |
281 | |
282 | if ( my $afh = $self->{audit_fh} ) { |
aa83bc1e |
283 | flock( $afh, LOCK_EX ); |
284 | |
285 | if ( $string =~ /^#/ ) { |
286 | print( $afh "$string " . localtime(time) . "\n" ); |
287 | } |
288 | else { |
289 | print( $afh "$string # " . localtime(time) . "\n" ); |
290 | } |
291 | |
292 | flock( $afh, LOCK_UN ); |
293 | } |
294 | |
25c7c8d6 |
295 | if ( $self->{trans_audit} ) { |
296 | push @{$self->{trans_audit}}, $string; |
297 | } |
298 | |
aa83bc1e |
299 | return 1; |
300 | } |
301 | |
28394a1a |
302 | sub begin_transaction { |
303 | my $self = shift; |
304 | |
15ba72cc |
305 | my $fh = $self->{fh}; |
306 | |
20b7f047 |
307 | $self->lock; |
308 | |
aa83bc1e |
309 | seek( $fh, $self->{transaction_offset} + $self->{file_offset}, SEEK_SET ); |
20b7f047 |
310 | my $buffer; |
311 | read( $fh, $buffer, 4 ); |
312 | $buffer = unpack( 'N', $buffer ); |
313 | |
314 | for ( 1 .. 32 ) { |
315 | next if $buffer & (1 << ($_ - 1)); |
316 | $self->{transaction_id} = $_; |
c9b6d0d8 |
317 | $buffer |= (1 << $_-1 ); |
20b7f047 |
318 | last; |
319 | } |
320 | |
aa83bc1e |
321 | seek( $fh, $self->{transaction_offset} + $self->{file_offset}, SEEK_SET ); |
20b7f047 |
322 | print( $fh pack( 'N', $buffer ) ); |
15ba72cc |
323 | |
20b7f047 |
324 | $self->unlock; |
325 | |
25c7c8d6 |
326 | $self->{trans_audit} = []; |
327 | |
20b7f047 |
328 | return $self->{transaction_id}; |
28394a1a |
329 | } |
330 | |
331 | sub end_transaction { |
332 | my $self = shift; |
333 | |
20b7f047 |
334 | my $fh = $self->{fh}; |
335 | |
336 | $self->lock; |
337 | |
aa83bc1e |
338 | seek( $fh, $self->{transaction_offset} + $self->{file_offset}, SEEK_SET ); |
20b7f047 |
339 | my $buffer; |
340 | read( $fh, $buffer, 4 ); |
341 | $buffer = unpack( 'N', $buffer ); |
342 | |
343 | # Unset $self->{transaction_id} bit |
25c7c8d6 |
344 | $buffer ^= (1 << $self->{transaction_id}-1); |
20b7f047 |
345 | |
aa83bc1e |
346 | seek( $fh, $self->{transaction_offset} + $self->{file_offset}, SEEK_SET ); |
20b7f047 |
347 | print( $fh pack( 'N', $buffer ) ); |
348 | |
349 | $self->unlock; |
15ba72cc |
350 | |
28394a1a |
351 | $self->{transaction_id} = 0; |
25c7c8d6 |
352 | $self->{trans_audit} = undef; |
353 | |
354 | return 1; |
28394a1a |
355 | } |
356 | |
20b7f047 |
357 | sub current_transactions { |
28394a1a |
358 | my $self = shift; |
359 | |
20b7f047 |
360 | my $fh = $self->{fh}; |
361 | |
362 | $self->lock; |
363 | |
aa83bc1e |
364 | seek( $fh, $self->{transaction_offset} + $self->{file_offset}, SEEK_SET ); |
20b7f047 |
365 | my $buffer; |
366 | read( $fh, $buffer, 4 ); |
367 | $buffer = unpack( 'N', $buffer ); |
368 | |
369 | $self->unlock; |
370 | |
371 | my @transactions; |
372 | for ( 1 .. 32 ) { |
373 | if ( $buffer & (1 << ($_ - 1)) ) { |
374 | push @transactions, $_; |
375 | } |
376 | } |
377 | |
c9b6d0d8 |
378 | return grep { $_ != $self->{transaction_id} } @transactions; |
28394a1a |
379 | } |
380 | |
20b7f047 |
381 | sub transaction_id { return $_[0]->{transaction_id} } |
382 | |
25c7c8d6 |
383 | sub commit_transaction { |
384 | my $self = shift; |
385 | |
386 | my @audit = @{$self->{trans_audit}}; |
387 | |
388 | $self->end_transaction; |
389 | |
390 | { |
391 | my $db = $self->{base_db_obj}; |
392 | for ( @audit ) { |
393 | eval "$_;"; |
394 | warn "$_: $@\n" if $@; |
395 | } |
396 | } |
397 | |
398 | return 1; |
399 | } |
28394a1a |
400 | |
460b1067 |
401 | 1; |
402 | __END__ |
403 | |