X-Git-Url: http://git.rot13.org/?p=Fuse-DBI;a=blobdiff_plain;f=DBI.pm;h=425822dccc1b8ac4bd9161ce80297e0d24156bba;hp=c8572cee20465aff28d65c5243e721bbc9897b97;hb=863d1b67dbbb3c6d42e21567f6d30bcafaea334b;hpb=f1bc65fc4ababc69dc1478b2b7557ab93dfb1c63 diff --git a/DBI.pm b/DBI.pm index c8572ce..425822d 100755 --- a/DBI.pm +++ b/DBI.pm @@ -12,8 +12,10 @@ use DBI; use Carp; use Data::Dumper; +our $VERSION = '0.09_1'; -our $VERSION = '0.06'; +# block size for this filesystem +use constant BLOCK => 1024; =head1 NAME @@ -109,6 +111,25 @@ running. Implementation is experimental. =back +There is also alternative way which can generate C and C +queries on the fly: + + my $mnt = Fuse::DBI->mount({ + 'filenames' => 'select id,filename,size,writable from files', + 'read' => sub { + my ($path,$file) = @_; + return( 'select content from files where id = ?', $file->{row}->{id} ); + }, + 'update' => sub { + my ($path,$file) = @_; + return( 'update files set content = ? where id = ?', $file->{row}->{id} ); + }, + 'dsn' => 'DBI:Pg:dbname=test_db', + 'user' => 'database_user', + 'password' => 'database_password', + 'invalidate' => sub { ... }, + }); + =cut my $dbh; @@ -123,6 +144,8 @@ sub fuse_module_loaded; # be a problem. my $fuse_self; +my $debug = 0; + sub mount { my $class = shift; my $self = {}; @@ -132,6 +155,11 @@ sub mount { print Dumper($arg); + unless ($self->fuse_module_loaded) { + print STDERR "no fuse module loaded. Trying sudo modprobe fuse!\n"; + system "sudo modprobe fuse" || die "can't modprobe fuse using sudo!\n"; + } + carp "mount needs 'dsn' to connect to (e.g. dsn => 'DBI:Pg:dbname=test')" unless ($arg->{'dsn'}); carp "mount needs 'mount' as mountpoint" unless ($arg->{'mount'}); @@ -152,7 +180,16 @@ sub mount { die "fork() failed: $!" unless defined $pid; # child will return to caller if ($pid) { - return $self; + my $counter = 4; + while ($counter && ! $self->is_mounted) { + select(undef, undef, undef, 0.5); + $counter--; + } + if ($self->is_mounted) { + return $self; + } else { + return undef; + } } } @@ -160,16 +197,24 @@ sub mount { $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(); - - $self->{'sth'} = $sth; + $self->{'dbh'} = $dbh; $self->{'read_filenames'} = sub { $self->read_filenames }; $self->read_filenames; - $fuse_self = \$self; + foreach my $op (qw/read update/) { + if (ref($arg->{ $op }) ne 'CODE') { + $self->{ $op . '_ref' } = sub { + my $row = shift; + return ($arg->{ $op }, $row->{'id'}); + } + } else { + $self->{ $op . '_ref' } = $arg->{ $op }; + } + } + + $fuse_self = $self; Fuse::main( mountpoint=>$arg->{'mount'}, @@ -183,7 +228,7 @@ sub mount { truncate=>\&e_truncate, unlink=>\&e_unlink, rmdir=>\&e_unlink, - debug=>0, + debug=>$debug, ); exit(0) if ($arg->{'fork'}); @@ -192,6 +237,32 @@ sub mount { }; +=head2 is_mounted + +Check if fuse filesystem is mounted + + if ($mnt->is_mounted) { ... } + +=cut + +sub is_mounted { + my $self = shift; + + my $mounted = 0; + my $mount = $self->{'mount'} || confess "can't find mount point!"; + if (open(MTAB, "/etc/mtab")) { + while() { + $mounted = 1 if (/ $mount fuse /i); + } + close(MTAB); + } else { + warn "can't open /etc/mtab: $!"; + } + + return $mounted; +} + + =head2 umount Unmount your database as filesystem. @@ -206,35 +277,27 @@ database to filesystem. sub umount { my $self = shift; - if ($self->{'mount'}) { - if (open(MTAB, "/etc/mtab")) { - my $mounted = 0; - my $mount = $self->{'mount'}; - while() { - $mounted = 1 if (/ $mount fuse /i); - } - close(MTAB); - - if ($mounted) { - system "fusermount -u ".$self->{'mount'}." 2>&1 >/dev/null" || return 0; - return 1; - } - - } else { - warn "can't open /etc/mtab: $!"; + if ($self->{'mount'} && $self->is_mounted) { + system "( fusermount -u ".$self->{'mount'}." 2>&1 ) >/dev/null"; + sleep 1; + if ($self->is_mounted) { + system "sudo umount ".$self->{'mount'} || return 0; } + return 1; } + + return 0; } $SIG{'INT'} = sub { - if ($fuse_self && $$fuse_self->umount) { + if ($fuse_self && $fuse_self->can('umount')) { print STDERR "umount called by SIG INT\n"; } }; $SIG{'QUIT'} = sub { - if ($fuse_self && $$fuse_self->umount) { + if ($fuse_self && $fuse_self->can('umount')) { print STDERR "umount called by SIG QUIT\n"; } }; @@ -267,8 +330,7 @@ sub fuse_module_loaded { } } -my %files; -my %dirs; +my $files; sub read_filenames { my $self = shift; @@ -276,7 +338,7 @@ sub read_filenames { my $sth = $self->{'sth'} || die "no sth argument"; # create empty filesystem - (%files) = ( + $files = { '.' => { type => 0040, mode => 0755, @@ -290,33 +352,35 @@ sub read_filenames { # 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'}} = { + $row->{'filename'} ||= 'NULL-'.$row->{'id'}; + $files->{$row->{'filename'}} = { size => $row->{'size'}, mode => $row->{'writable'} ? 0644 : 0444, - id => $row->{'id'} || 99, + id => $row->{'id'} || undef, + row => $row, }; + my $d; foreach (split(m!/!, $row->{'filename'})) { # first, entry is assumed to be file if ($d) { - $files{$d} = { - size => $dirs{$d}++, + $files->{$d} = { mode => 0755, type => 0040 }; - $files{$d.'/.'} = { + $files->{$d.'/.'} = { mode => 0755, type => 0040 }; - $files{$d.'/..'} = { + $files->{$d.'/..'} = { mode => 0755, type => 0040 }; @@ -326,7 +390,7 @@ sub read_filenames { } } - print "found ",scalar(keys %files)-scalar(keys %dirs)," files, ",scalar(keys %dirs), " dirs\n"; + print "found ",scalar(keys %{$files})," files\n"; } @@ -341,17 +405,17 @@ sub e_getattr { my ($file) = filename_fixup(shift); $file =~ s,^/,,; $file = '.' unless length($file); - return -ENOENT() unless exists($files{$file}); - my ($size) = $files{$file}{size} || 1; - my ($dev, $ino, $rdev, $blocks, $gid, $uid, $nlink, $blksize) = (0,0,0,1,0,0,1,1024); + return -ENOENT() unless exists($files->{$file}); + my ($size) = $files->{$file}->{size} || 0; + my ($dev, $ino, $rdev, $blocks, $gid, $uid, $nlink, $blksize) = (0,0,0,int(($size+BLOCK-1)/BLOCK),0,0,1,BLOCK); my ($atime, $ctime, $mtime); - $atime = $ctime = $mtime = $files{$file}{ctime} || $ctime_start; + $atime = $ctime = $mtime = $files->{$file}->{ctime} || $ctime_start; - my ($modes) = (($files{$file}{type} || 0100)<<9) + $files{$file}{mode}; + my ($modes) = (($files->{$file}->{type} || 0100)<<9) + $files->{$file}->{mode}; # 2 possible types of return values: #return -ENOENT(); # or any other error you care to - #print(join(",",($dev,$ino,$modes,$nlink,$uid,$gid,$rdev,$size,$atime,$mtime,$ctime,$blksize,$blocks)),"\n"); + #print "getattr($file) ",join(",",($dev,$ino,$modes,$nlink,$uid,$gid,$rdev,$size,$atime,$mtime,$ctime,$blksize,$blocks)),"\n"; return ($dev,$ino,$modes,$nlink,$uid,$gid,$rdev,$size,$atime,$mtime,$ctime,$blksize,$blocks); } @@ -359,9 +423,9 @@ sub e_getdir { my ($dirname) = shift; $dirname =~ s!^/!!; # return as many text filenames as you like, followed by the retval. - print((scalar keys %files)." files total\n"); + print((scalar keys %{$files})." files total\n"); my %out; - foreach my $f (sort keys %files) { + foreach my $f (sort keys %{$files}) { if ($dirname) { if ($f =~ s/^\Q$dirname\E\///) { $out{$f}++ if ($f =~ /^[^\/]+$/); @@ -379,15 +443,21 @@ sub e_getdir { } sub read_content { - my ($file,$id) = @_; + my $file = shift || die "need file"; + + warn "# read_content($file)\n" if ($debug); + + my @args = $fuse_self->{'read_ref'}->($files->{$file}); + my $sql = shift @args || die "need SQL for $file"; - die "read_content needs file and id" unless ($file && $id); + $fuse_self->{'read_sth'}->{$sql} ||= $fuse_self->{dbh}->prepare($sql) || die $dbh->errstr(); + my $sth = $fuse_self->{'read_sth'}->{$sql} || die; - $sth->{'read'}->execute($id) || die $sth->{'read'}->errstr; - $files{$file}{cont} = $sth->{'read'}->fetchrow_array; + $sth->execute(@args) || die $sth->errstr; + $files->{$file}->{cont} = $sth->fetchrow_array; # I should modify ctime only if content in database changed - #$files{$file}{ctime} = time() unless ($files{$file}{ctime}); - print "file '$file' content [",length($files{$file}{cont})," bytes] read in cache\n"; + #$files->{$file}->{ctime} = time() unless ($files->{$file}->{ctime}); + print "file '$file' content [",length($files->{$file}->{cont})," bytes] read in cache\n"; } @@ -396,12 +466,13 @@ sub e_open { my $file = filename_fixup(shift); my $flags = shift; - return -ENOENT() unless exists($files{$file}); - return -EISDIR() unless exists($files{$file}{id}); + return -ENOENT() unless exists($files->{$file}); + return -EISDIR() unless exists($files->{$file}->{id}); - read_content($file,$files{$file}{id}) unless exists($files{$file}{cont}); + read_content($file,$files->{$file}->{id}) unless exists($files->{$file}->{cont}); - print "open '$file' ",length($files{$file}{cont})," bytes\n"; + $files->{$file}->{cont} ||= ''; + print "open '$file' ",length($files->{$file}->{cont})," bytes\n"; return 0; } @@ -412,9 +483,9 @@ sub e_read { my ($file) = filename_fixup(shift); my ($buf_len,$off) = @_; - return -ENOENT() unless exists($files{$file}); + return -ENOENT() unless exists($files->{$file}); - my $len = length($files{$file}{cont}); + my $len = length($files->{$file}->{cont}); print "read '$file' [$len bytes] offset $off length $buf_len\n"; @@ -423,16 +494,16 @@ sub e_read { $buf_len = $len-$off if ($len - $off < $buf_len); - return substr($files{$file}{cont},$off,$buf_len); + return substr($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}; - delete $files{$f}{ctime}; + foreach my $f (keys %{$files}) { + delete $files->{$f}->{cont}; + delete $files->{$f}->{ctime}; } print "begin new transaction\n"; #$dbh->begin_work || die $dbh->errstr; @@ -440,28 +511,40 @@ sub clear_cont { sub update_db { - my $file = shift || die; + my $file = shift || die "need file"; - $files{$file}{ctime} = time(); + $files->{$file}->{ctime} = time(); my ($cont,$id) = ( - $files{$file}{cont}, - $files{$file}{id} + $files->{$file}->{cont}, + $files->{$file}->{id} ); - if (!$sth->{'update'}->execute($cont,$id)) { - print "update problem: ",$sth->{'update'}->errstr; + my @args = $fuse_self->{'update_ref'}->($files->{$file}); + + my $sql = shift @args || die "need SQL for $file"; + + unshift @args, $files->{$file}->{cont} if ($#args == 0); + + warn "## SQL: $sql\n# files->{$file} = ", Dumper($files->{$file}), $/ if ($debug); + + my $sth = $fuse_self->{'update_sth'}->{$sql} + ||= $fuse_self->{dbh}->prepare($sql) + || die $dbh->errstr(); + + if (!$sth->execute(@args)) { + print "update problem: ",$sth->errstr; clear_cont; return 0; } else { if (! $dbh->commit) { - print "ERROR: commit problem: ",$sth->{'update'}->errstr; + print "ERROR: commit problem: ",$sth->errstr; clear_cont; return 0; } - print "updated '$file' [",$files{$file}{id},"]\n"; + print "updated '$file' [",$files->{$file}->{id},"]\n"; - $$fuse_self->{'invalidate'}->() if (ref $$fuse_self->{'invalidate'}); + $fuse_self->{'invalidate'}->() if ($fuse_self->can('invalidate')); } return 1; } @@ -470,20 +553,20 @@ sub e_write { my $file = filename_fixup(shift); my ($buffer,$off) = @_; - return -ENOENT() unless exists($files{$file}); + return -ENOENT() unless exists($files->{$file}); - my $cont = $files{$file}{cont}; + my $cont = $files->{$file}->{cont}; my $len = length($cont); print "write '$file' [$len bytes] offset $off length ",length($buffer),"\n"; - $files{$file}{cont} = ""; + $files->{$file}->{cont} = ""; - $files{$file}{cont} .= substr($cont,0,$off) if ($off > 0); - $files{$file}{cont} .= $buffer; - $files{$file}{cont} .= substr($cont,$off+length($buffer),$len-$off-length($buffer)) if ($off+length($buffer) < $len); + $files->{$file}->{cont} .= substr($cont,0,$off) if ($off > 0); + $files->{$file}->{cont} .= $buffer; + $files->{$file}->{cont} .= substr($cont,$off+length($buffer),$len-$off-length($buffer)) if ($off+length($buffer) < $len); - $files{$file}{size} = length($files{$file}{cont}); + $files->{$file}->{size} = length($files->{$file}->{cont}); if (! update_db($file)) { return -ENOSYS(); @@ -498,8 +581,8 @@ sub e_truncate { print "truncate to $size\n"; - $files{$file}{cont} = substr($files{$file}{cont},0,$size); - $files{$file}{size} = $size; + $files->{$file}->{cont} = substr($files->{$file}->{cont},0,$size); + $files->{$file}->{size} = $size; return 0 }; @@ -508,27 +591,47 @@ sub e_utime { my ($atime,$mtime,$file) = @_; $file = filename_fixup($file); - return -ENOENT() unless exists($files{$file}); + return -ENOENT() unless exists($files->{$file}); print "utime '$file' $atime $mtime\n"; - $files{$file}{time} = $mtime; + $files->{$file}->{time} = $mtime; return 0; } -sub e_statfs { return 255, 1, 1, 1, 1, 2 } +sub e_statfs { + + my $size = 0; + my $inodes = 0; + + foreach my $f (keys %{$files}) { + if ($f !~ /(^|\/)\.\.?$/) { + $size += $files->{$f}->{size} || 0; + $inodes++; + } + print "$inodes: $f [$size]\n"; + } + + $size = int(($size+BLOCK-1)/BLOCK); + + my @ret = (255, $inodes, 1, $size, $size-1, BLOCK); + + #print "statfs: ",join(",",@ret),"\n"; + + return @ret; +} sub e_unlink { my $file = filename_fixup(shift); - if (exists( $dirs{$file} )) { - print "unlink '$file' will re-read template names\n"; - print Dumper($fuse_self); - $$fuse_self->{'read_filenames'}->(); - return 0; - } elsif (exists( $files{$file} )) { +# if (exists( $dirs{$file} )) { +# print "unlink '$file' will re-read template names\n"; +# print Dumper($fuse_self); +# $fuse_self->{'read_filenames'}->(); +# return 0; + if (exists( $files->{$file} )) { print "unlink '$file' will invalidate cache\n"; - read_content($file,$files{$file}{id}); + read_content($file,$files->{$file}->{id}); return 0; }