1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
| | # Copyright (C) 2020-2021 all contributors <meta@public-inbox.org>
# License: AGPL-3.0+ <https://www.gnu.org/licenses/agpl-3.0.txt>
# fork()-friendly key-value store. Will be used for making
# augmenting Maildirs and mboxes less expensive, maybe.
# We use flock(2) to avoid SQLite lock problems (busy timeouts, backoff)
package PublicInbox::SharedKV;
use strict;
use v5.10.1;
use parent qw(PublicInbox::Lock);
use File::Temp qw(tempdir);
use DBI ();
use PublicInbox::Spawn;
use File::Path qw(rmtree make_path);
sub dbh {
my ($self, $lock) = @_;
$self->{dbh} // do {
my $f = $self->{filename};
$lock //= $self->lock_for_scope_fast;
my $dbh = DBI->connect("dbi:SQLite:dbname=$f", '', '', {
AutoCommit => 1,
RaiseError => 1,
PrintError => 0,
sqlite_use_immediate_transaction => 1,
# no sqlite_unicode here, this is for binary data
});
my $opt = $self->{opt} // {};
$dbh->do('PRAGMA synchronous = OFF') if !$opt->{fsync};
$dbh->do('PRAGMA journal_mode = '.
($opt->{journal_mode} // 'WAL'));
$dbh->do(<<'');
CREATE TABLE IF NOT EXISTS kv (
k VARBINARY PRIMARY KEY NOT NULL,
v VARBINARY NOT NULL,
UNIQUE (k)
)
$self->{dbh} = $dbh;
}
}
sub new {
my ($cls, $dir, $base, $opt) = @_;
my $self = bless { opt => $opt }, $cls;
make_path($dir) if defined($dir) && !-d $dir;
$dir //= $self->{"tmp$$.$self"} = tempdir("skv.$$-XXXX", TMPDIR => 1);
$base //= '';
my $f = $self->{filename} = "$dir/$base.sqlite3";
$self->{lock_path} = $opt->{lock_path} // "$dir/$base.flock";
unless (-s $f) {
PublicInbox::Spawn::nodatacow_dir($dir); # for journal/shm/wal
open my $fh, '+>>', $f or die "failed to open $f: $!";
PublicInbox::Spawn::nodatacow_fd(fileno($fh));
}
$self;
}
sub index_values {
my ($self) = @_;
my $lock = $self->lock_for_scope_fast;
$self->dbh($lock)->do('CREATE INDEX IF NOT EXISTS idx_v ON kv (v)');
}
sub set_maybe {
my ($self, $key, $val, $lock) = @_;
$lock //= $self->lock_for_scope_fast;
my $e = $self->{dbh}->prepare_cached(<<'')->execute($key, $val);
INSERT OR IGNORE INTO kv (k,v) VALUES (?, ?)
$e == 0 ? undef : $e;
}
# caller calls sth->fetchrow_array
sub each_kv_iter {
my ($self) = @_;
my $sth = $self->{dbh}->prepare_cached(<<'', undef, 1);
SELECT k,v FROM kv
$sth->execute;
$sth
}
sub keys {
my ($self, @pfx) = @_;
my $sql = 'SELECT k FROM kv';
if (defined $pfx[0]) {
$sql .= ' WHERE k LIKE ? ESCAPE ?';
my $anywhere = !!$pfx[1];
$pfx[1] = '\\';
$pfx[0] =~ s/([%_\\])/\\$1/g; # glob chars
$pfx[0] .= '%';
substr($pfx[0], 0, 0, '%') if $anywhere;
} else {
@pfx = (); # [0] may've been undef
}
map { $_->[0] } @{$self->dbh->selectall_arrayref($sql, undef, @pfx)};
}
sub delete_by_val {
my ($self, $val, $lock) = @_;
$lock //= $self->lock_for_scope_fast;
$self->{dbh}->prepare_cached(<<'')->execute($val) + 0;
DELETE FROM kv WHERE v = ?
}
sub replace_values {
my ($self, $oldval, $newval, $lock) = @_;
$lock //= $self->lock_for_scope_fast;
$self->{dbh}->prepare_cached(<<'')->execute($newval, $oldval) + 0;
UPDATE kv SET v = ? WHERE v = ?
}
sub set {
my ($self, $key, $val) = @_;
if (defined $val) {
my $e = $self->{dbh}->prepare_cached(<<'')->execute($key, $val);
INSERT OR REPLACE INTO kv (k,v) VALUES (?,?)
$e == 0 ? undef : $e;
} else {
$self->{dbh}->prepare_cached(<<'')->execute($key);
DELETE FROM kv WHERE k = ?
}
}
sub get {
my ($self, $key) = @_;
my $sth = $self->{dbh}->prepare_cached(<<'', undef, 1);
SELECT v FROM kv WHERE k = ?
$sth->execute($key);
$sth->fetchrow_array;
}
sub xchg {
my ($self, $key, $newval, $lock) = @_;
$lock //= $self->lock_for_scope_fast;
my $oldval = get($self, $key);
if (defined $newval) {
set($self, $key, $newval);
} else {
$self->{dbh}->prepare_cached(<<'')->execute($key);
DELETE FROM kv WHERE k = ?
}
$oldval;
}
sub count {
my ($self) = @_;
my $sth = $self->{dbh}->prepare_cached(<<'');
SELECT COUNT(k) FROM kv
$sth->execute;
$sth->fetchrow_array;
}
# faster than ->count due to how SQLite works
sub has_entries {
my ($self) = @_;
my @n = $self->{dbh}->selectrow_array('SELECT k FROM kv LIMIT 1');
scalar(@n) ? 1 : undef;
}
sub dbh_release {
my ($self, $lock) = @_;
my $dbh = delete $self->{dbh} or return;
$lock //= $self->lock_for_scope_fast; # may be needed for WAL
%{$dbh->{CachedKids}} = (); # cleanup prepare_cached
$dbh->disconnect;
}
sub DESTROY {
my ($self) = @_;
dbh_release($self);
my $dir = delete $self->{"tmp$$.$self"} or return;
my $tries = 0;
do {
$! = 0;
eval { rmtree($dir) };
} while ($@ && $!{ENOENT} && $tries++ < 5);
warn "error removing $dir: $@" if $@;
warn "Took $tries tries to remove $dir\n" if $tries;
}
1;
|