--- trunk/fuse_dbi.pl 2004/08/04 16:17:09 6 +++ trunk/DBI.pm 2004/08/29 20:12:37 13 @@ -1,94 +1,208 @@ #!/usr/bin/perl -use POSIX qw(ENOENT EISDIR EINVAL O_RDWR); -use Fuse; +package Fuse::DBI; -use DBI; +use 5.008; use strict; +use warnings; -my $sql_filenames = q{ - select - oid as id, - namespace||'/'||name||' ['||oid||']' as filename, - length(template) as size, - iseditable as writable - from template ; -}; +use POSIX qw(ENOENT EISDIR EINVAL ENOSYS O_RDWR); +use Fuse; +use DBI; +use Carp; +use Proc::Simple; +use Data::Dumper; -my $sql_read = q{ - select template - from template - where oid = ?; -}; -my $sql_update = q{ - update template - set template = ? - where oid = ?; +our $VERSION = '0.01'; + +=head1 NAME + +Fuse::DBI - mount your database as filesystem and use it + +=head1 SYNOPSIS + + use Fuse::DBI; + Fuse::DBI->mount( ... ); + +See L below for examples how to set parametars. + +=head1 DESCRIPTION + +This module will use L module, part of C +available at L to mount +your database as file system. + +That will give you posibility to use normal file-system tools (cat, grep, vi) +to manipulate data in database. + +It's actually opposite of Oracle's intention to put everything into database. + + +=head1 METHODS + +=cut + +=head2 mount + +Mount your database as filesystem. + + my $mnt = Fuse::DBI->mount({ + filenames => 'select name from filenamefilenames, + read => 'sql read', + update => 'sql update', + dsn => 'DBI:Pg:dbname=webgui', + user => 'database_user', + password => 'database_password' + }); + +=cut + +my $dbh; +my $sth; +my $ctime_start; + +sub read_filenames; + +sub mount { + my $class = shift; + my $self = {}; + bless($self, $class); + + my $arg = shift; + + print Dumper($arg); + + carp "mount needs 'dsn' to connect to (e.g. dsn => 'DBI:Pg:dbname=test')" unless ($arg->{'dsn'}); + carp "mount needs 'mount' as mountpoint" unless ($arg->{'mount'}); + + # save (some) arguments in self + $self->{$_} = $arg->{$_} foreach (qw(mount)); + + foreach (qw(filenames read update)) { + carp "mount needs '$_' SQL" unless ($arg->{$_}); + } + + $dbh = DBI->connect($arg->{'dsn'},$arg->{'user'},$arg->{'password'}, { AutoCommit => 0 }) || die $DBI::errstr; + + print "start transaction\n"; + #$dbh->begin_work || die $dbh->errstr; + + $sth->{filenames} = $dbh->prepare($arg->{'filenames'}) || die $dbh->errstr(); + + $sth->{'read'} = $dbh->prepare($arg->{'read'}) || die $dbh->errstr(); + $sth->{'update'} = $dbh->prepare($arg->{'update'}) || die $dbh->errstr(); + + $ctime_start = time(); + + read_filenames; + + $self->{'proc'} = Proc::Simple->new(); + $self->{'proc'}->kill_on_destroy(1); + + $self->{'proc'}->start( sub { + Fuse::main( + mountpoint=>$arg->{'mount'}, + getattr=>\&e_getattr, + getdir=>\&e_getdir, + open=>\&e_open, + statfs=>\&e_statfs, + read=>\&e_read, + write=>\&e_write, + utime=>\&e_utime, + truncate=>\&e_truncate, + debug=>0, + ); + } ); + + confess "Fuse::main failed" if (! $self->{'proc'}->poll); + + $self ? return $self : return undef; }; +=head2 umount -my $connect = "DBI:Pg:dbname=webgui"; +Unmount your database as filesystem. -my $dbh = DBI->connect($connect,"","") || die $DBI::errstr; + $mnt->umount; -print STDERR "$sql_filenames\n"; +This will also kill background process which is translating +database to filesystem. -my $sth_filenames = $dbh->prepare($sql_filenames) || die $dbh->errstr(); -$sth_filenames->execute() || die $sth_filenames->errstr(); +=cut -my $sth_read = $dbh->prepare($sql_read) || die $dbh->errstr(); -my $sth_update = $dbh->prepare($sql_update) || die $dbh->errstr(); +sub umount { + my $self = shift; -print "#",join(",",@{ $sth_filenames->{NAME} }),"\n"; + confess "no process running?" unless ($self->{'proc'}); -my $ctime_start = time(); + system "fusermount -u ".$self->{'mount'} || croak "umount error: $!"; + + if ($self->{'proc'}->poll) { + $self->{'proc'}->kill; + return 1 if (! $self->{'proc'}->poll); + } else { + return 1; + } +} -my (%files) = ( - '.' => { - type => 0040, - mode => 0755, - }, -# a => { -# cont => "File 'a'.\n", -# type => 0100, -# ctime => time()-2000 -# }, -); +my %files; my %dirs; -while (my $row = $sth_filenames->fetchrow_hashref() ) { - $files{$row->{'filename'}} = { - size => $row->{'size'}, - mode => $row->{'writable'} ? 0644 : 0444, - id => $row->{'id'} || 99, - }; - - my $d; - foreach (split(m!/!, $row->{'filename'})) { - # first, entry is assumed to be file - if ($d) { - $files{$d} = { - size => $dirs{$d}++, - mode => 0755, - type => 0040 - }; - $files{$d.'/.'} = { - mode => 0755, - type => 0040 - }; - $files{$d.'/..'} = { - mode => 0755, - type => 0040 - }; +sub read_filenames { + my $self = shift; + + # create empty filesystem + (%files) = ( + '.' => { + type => 0040, + mode => 0755, + }, + # a => { + # cont => "File 'a'.\n", + # type => 0100, + # ctime => time()-2000 + # }, + ); + + # fetch new filename list from database + $sth->{'filenames'}->execute() || die $sth->{'filenames'}->errstr(); + + # read them in with sesible defaults + while (my $row = $sth->{'filenames'}->fetchrow_hashref() ) { + $files{$row->{'filename'}} = { + size => $row->{'size'}, + mode => $row->{'writable'} ? 0644 : 0444, + id => $row->{'id'} || 99, + }; + + my $d; + foreach (split(m!/!, $row->{'filename'})) { + # first, entry is assumed to be file + if ($d) { + $files{$d} = { + size => $dirs{$d}++, + mode => 0755, + type => 0040 + }; + $files{$d.'/.'} = { + mode => 0755, + type => 0040 + }; + $files{$d.'/..'} = { + mode => 0755, + type => 0040 + }; + } + $d .= "/" if ($d); + $d .= "$_"; } - $d .= "/" if ($d); - $d .= "$_"; } + + print "found ",scalar(keys %files)-scalar(keys %dirs)," files, ",scalar(keys %dirs), " dirs\n"; } -print scalar (keys %dirs), " dirs:",join(" ",keys %dirs),"\n"; sub filename_fixup { my ($file) = shift; @@ -121,26 +235,23 @@ # return as many text filenames as you like, followed by the retval. print((scalar keys %files)." files total\n"); my %out; - foreach (keys %files) { - my $f = $_; - $f =~ s/^\E$dirname\Q//; - $f =~ s/^\///; + foreach my $f (sort keys %files) { if ($dirname) { - $out{$f}++ if (/^\E$dirname\Q/ && $f =~ /^[^\/]+$/); + if ($f =~ s/^\E$dirname\Q\///) { + $out{$f}++ if ($f =~ /^[^\/]+$/); + } } else { $out{$f}++ if ($f =~ /^[^\/]+$/); } - print "f: $_ -> $f\n"; } if (! %out) { $out{'no files? bug?'}++; } - print scalar keys %out," files found for '$dirname': ",keys %out,"\n"; + print scalar keys %out," files in dir '$dirname'\n"; + print "## ",join(" ",keys %out),"\n"; return (keys %out),0; } -my $in_transaction = 0; - sub e_open { # VFS sanity check; it keeps all the necessary state, not much to do here. my $file = filename_fixup(shift); @@ -149,19 +260,10 @@ return -ENOENT() unless exists($files{$file}); return -EISDIR() unless exists($files{$file}{id}); - if (! $in_transaction) { - # begin transaction - if (! $dbh->begin_work) { - print "transaction begin: ",$dbh->errstr; - return -ENOENT(); - } - } - $in_transaction++; - print "files opened: $in_transaction\n"; - if (!exists($files{$file}{cont})) { - $sth_read->execute($files{$file}{id}) || die $sth_read->errstr; - $files{$file}{cont} = $sth_read->fetchrow_array; + $sth->{'read'}->execute($files{$file}{id}) || die $sth->{'read'}->errstr; + $files{$file}{cont} = $sth->{'read'}->fetchrow_array; + print "file '$file' content read in cache\n"; } print "open '$file' ",length($files{$file}{cont})," bytes\n"; return 0; @@ -172,45 +274,47 @@ # (note: 0 means EOF, "0" will give a byte (ascii "0") # to the reading program) my ($file) = filename_fixup(shift); - my ($buf,$off) = @_; + my ($buf_len,$off) = @_; return -ENOENT() unless exists($files{$file}); my $len = length($files{$file}{cont}); - print "read '$file' [$len bytes] offset $off length $buf\n"; + print "read '$file' [$len bytes] offset $off length $buf_len\n"; return -EINVAL() if ($off > $len); return 0 if ($off == $len); - $buf = $len-$off if ($off+$buf > $len); + $buf_len = $buf_len-$off if ($off+$buf_len > $len); - return substr($files{$file}{cont},$off,$buf); + return substr($files{$file}{cont},$off,$buf_len); } sub clear_cont { + print "transaction rollback\n"; + $dbh->rollback || die $dbh->errstr; print "invalidate all cached content\n"; foreach my $f (keys %files) { delete $files{$f}{cont}; } + print "begin new transaction\n"; + $dbh->begin_work || die $dbh->errstr; } sub update_db { my $file = shift || die; - if (!$sth_update->execute($files{$file}{cont},$files{$file}{id})) { - print "update problem: ",$sth_update->errstr; - $dbh->rollback; + $files{$file}{ctime} = time(); + + if (!$sth->{'update'}->execute($files{$file}{cont},$files{$file}{id})) { + print "update problem: ",$sth->{'update'}->errstr; clear_cont; - $dbh->begin_work; return 0; } else { - if ($dbh->commit) { - print "commit problem: ",$sth_update->errstr; - $dbh->rollback; + if (! $dbh->commit) { + print "ERROR: commit problem: ",$sth->{'update'}->errstr; clear_cont; - $dbh->begin_work; return 0; } print "updated '$file' [",$files{$file}{id},"]\n"; @@ -220,23 +324,23 @@ sub e_write { my $file = filename_fixup(shift); - my ($buf,$off) = @_; + my ($buf_len,$off) = @_; return -ENOENT() unless exists($files{$file}); my $len = length($files{$file}{cont}); - print "write '$file' [$len bytes] offset $off length $buf\n"; + print "write '$file' [$len bytes] offset $off length\n"; $files{$file}{cont} = substr($files{$file}{cont},0,$off) . - $buf . - substr($files{$file}{cont},$off+length($buf)); + $buf_len . + substr($files{$file}{cont},$off+length($buf_len)); if (! update_db($file)) { return -ENOSYS(); } else { - return length($buf); + return length($buf_len); } } @@ -255,25 +359,38 @@ return -ENOENT() unless exists($files{$file}); + print "utime '$file' $atime $mtime\n"; + $files{$file}{time} = $mtime; return 0; } sub e_statfs { return 255, 1, 1, 1, 1, 2 } -# If you run the script directly, it will run fusermount, which will in turn -# re-run this script. Hence the funky semantics. -my ($mountpoint) = ""; -$mountpoint = shift(@ARGV) if @ARGV; -Fuse::main( - mountpoint=>$mountpoint, - getattr=>\&e_getattr, - getdir=>\&e_getdir, - open=>\&e_open, - statfs=>\&e_statfs, - read=>\&e_read, - write=>\&e_write, - utime=>\&e_utime, - truncate=>\&e_truncate, - debug=>1, -); +1; +__END__ + +=head1 EXPORT + +Nothing. + +=head1 SEE ALSO + +C website +L + +=head1 AUTHOR + +Dobrica Pavlinusic, Edpavlin@rot13.orgE + +=head1 COPYRIGHT AND LICENSE + +Copyright (C) 2004 by Dobrica Pavlinusic + +This library is free software; you can redistribute it and/or modify +it under the same terms as Perl itself, either Perl version 5.8.4 or, +at your option, any later version of Perl 5 you may have available. + + +=cut +