--- trunk/DBI.pm	2005/04/26 19:57:51	54
+++ trunk/DBI.pm	2006/08/02 21:53:30	62
@@ -12,7 +12,7 @@
 use Carp;
 use Data::Dumper;
 
-our $VERSION = '0.07';
+our $VERSION = '0.09_1';
 
 # block size for this filesystem
 use constant BLOCK => 1024;
@@ -111,6 +111,25 @@
 
 =back
 
+There is also alternative way which can generate C<read> and C<update>
+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;
@@ -176,15 +195,23 @@
 
 	$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->{'read_filenames'} = sub { $self->read_filenames };
 	$self->read_filenames;
 
+	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(
@@ -199,7 +226,7 @@
 		truncate=>\&e_truncate,
 		unlink=>\&e_unlink,
 		rmdir=>\&e_unlink,
-		debug=>0,
+		debug=>1,
 	);
 	
 	exit(0) if ($arg->{'fork'});
@@ -300,7 +327,7 @@
 	}
 }
 
-my %files;
+my $files;
 
 sub read_filenames {
 	my $self = shift;
@@ -308,7 +335,7 @@
 	my $sth = $self->{'sth'} || die "no sth argument";
 
 	# create empty filesystem
-	(%files) = (
+	$files = {
 		'.' => {
 			type => 0040,
 			mode => 0755,
@@ -322,32 +349,35 @@
 	#		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} = {
+				$files->{$d} = {
 						mode => 0755,
 						type => 0040
 				};
-				$files{$d.'/.'} = {
+				$files->{$d.'/.'} = {
 						mode => 0755,
 						type => 0040
 				};
-				$files{$d.'/..'} = {
+				$files->{$d.'/..'} = {
 						mode => 0755,
 						type => 0040
 				};
@@ -357,7 +387,7 @@
 		}
 	}
 
-	print "found ",scalar(keys %files)," files\n";
+	print "found ",scalar(keys %{$files})," files\n";
 }
 
 
@@ -372,13 +402,13 @@
 	my ($file) = filename_fixup(shift);
 	$file =~ s,^/,,;
 	$file = '.' unless length($file);
-	return -ENOENT() unless exists($files{$file});
-	my ($size) = $files{$file}{size} || 0;
+	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
@@ -390,9 +420,9 @@
 	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 ($f =~ /^[^\/]+$/);
@@ -410,15 +440,21 @@
 }
 
 sub read_content {
-	my ($file,$id) = @_;
+	my $file = shift || die "need file";
+
+	warn "file: $file\n", Dumper($fuse_self);
+
+	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->{sth}->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";
 }
 
 
@@ -427,13 +463,13 @@
 	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});
 
-	$files{$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;
 }
 
@@ -444,9 +480,9 @@
 	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";
 
@@ -455,16 +491,16 @@
 
 	$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;
@@ -472,26 +508,33 @@
 
 
 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 = $$fuse_self->{'update_ref'}->($files->{$file});
+	my $sql = shift @args || die "need SQL for $file";
+
+	my $sth = $$fuse_self->{'update_sth'}->{$sql}
+		||= $$fuse_self->{sth}->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'});
 	}
@@ -502,20 +545,20 @@
 	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();
@@ -530,8 +573,8 @@
 
 	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
 };
 
@@ -540,11 +583,11 @@
 	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;
 }
 
@@ -553,9 +596,9 @@
 	my $size = 0;
 	my $inodes = 0;
 
-	foreach my $f (keys %files) {
+	foreach my $f (keys %{$files}) {
 		if ($f !~ /(^|\/)\.\.?$/) {
-			$size += $files{$f}{size} || 0;
+			$size += $files->{$f}->{size} || 0;
 			$inodes++;
 		}
 		print "$inodes: $f [$size]\n";
@@ -578,9 +621,9 @@
 #		print Dumper($fuse_self);
 #		$$fuse_self->{'read_filenames'}->();
 #		return 0;
-	if (exists( $files{$file} )) {
+	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;
 	}