--- fuse-comp.pl	2007/07/10 01:10:49	28
+++ fuse-comp.pl	2007/09/02 12:03:52	39
@@ -10,25 +10,29 @@
 use PerlIO::gzip;
 use File::Path;
 use Data::Dump qw/dump/;
-use Carp qw/confess/;
+use Carp qw/confess cluck/;
 use IO::File;
 use Getopt::Long;
 
 my $debug = 0;
 my $fuse_debug = 0;
+my $stats = 1;
 
 GetOptions(
 	'debug+' => \$debug,
 	'fuse-debug+' => \$fuse_debug,
+	'stats!' => \$stats,
 );
 
 my $mount = {
-	from	=> '/tmp/comp',
-	to		=> '/tmp/no-comp',
-	tmp		=> '/dev/shm/comp',
+	from	=> shift @ARGV || '/tmp/comp',
+	to		=> shift @ARGV || '/tmp/no-comp',
+	tmp		=> shift @ARGV || '/dev/shm/comp',
 };
 
-my $skip_extensions_regex = qr/\.(?:sw[a-z]|gif|png|jpeg|jpg|avi|rar|zip|bz2|gz|tgz|avi|mpeg|mpg|tmp|temp)$/i;
+warn "mount $mount->{from} to $mount->{to} using $mount->{tmp} as cache\n";
+
+my $skip_extensions_regex = qr/gz|gz%|\.(?:sw[a-z]|gif|png|jpeg|jpg|avi|rar|zip|bz2|tgz|avi|mpeg|mpg|tmp|temp)$/i;
 
 # don't compress files smaller than this
 my $min_compress_size = 512;
@@ -45,10 +49,14 @@
 sub real_name {
 	my ( $dir, $name ) = @_;
 	if ( -e "$dir/${name}.gz" ) {
-		confess "ASSERT: unexpected $dir/$name exists" if -e "$dir/$name";
+		cluck "ASSERT: unexpected $dir/$name exists" if -e "$dir/$name";
 		return "${name}.gz";
 	}
-	return $name;
+	if ( $name =~ m/\.gz$/ ) {
+		return $name . '%';	# protect (mingle) compressed files
+	} else {
+		return $name;
+	}
 }
 
 sub fixup {
@@ -59,6 +67,7 @@
 sub original_name {
 	my $p = shift;
 	$p =~ s/\.gz$//;
+	$p =~ s/\.gz%$/.gz/;	# demungle compressed .gz files
 	return $p;
 };
 
@@ -122,36 +131,68 @@
 	undef $s;
 }
 
-sub create_tmp_file {
+sub tmp_path {
 	my $file = shift;
 
 	my $path = fixup( $file );
-	my $tmp = $mount->{tmp} . '/' . $file;
-	if ( -e $tmp ) {
-		$path = $tmp;
-	} elsif ( $path =~ m/\.gz$/ ) {
-		my $dest_path = $tmp;
-		$dest_path =~ s!/[^/]+$!!;	#!vim-fix
-		mkpath $dest_path unless -e $dest_path;
-		if ( -s $path ) {
-			file_copy( '<:gzip', $path, '>', $tmp )
-		} else {
-			warn "ERROR: filesystem corruption, $path is zero size\n";
+
+	my $op = 'UNKNOWN';
+
+	if (defined( $pending->{$file} )) {
+		$path = $pending->{$file}->{path} || confess "no path for $file in ",dump( $pending );
+		$op = 'opened';
+	} else {
+		my $tmp = $mount->{tmp} . '/' . $file;
+		if ( -e $tmp ) {
+			$path = $tmp;
+			$op = 'existing';
+		} elsif ( $path =~ m/\.gz$/ ) {
+			my $dest_path = $tmp;
+			$dest_path =~ s!/[^/]+$!!;	#!vim-fix
+			mkpath $dest_path unless -e $dest_path;
+			if ( -s $path ) {
+				file_copy( '<:gzip', $path, '>', $tmp )
+			} else {
+				confess "ASSERT: filesystem corruption, $path is zero size in ",dump( $pending );
+			}
+			$path = $tmp;
+			$op = 'created';
 		}
-		$path = $tmp;
+		confess "ASSERT: path shouldn't exist for $file in ", dump( $pending ) if defined( $pending->{$file}->{path} );
+		confess "ASSERT: open shouldn't exist for $file in ", dump( $pending ) if defined( $pending->{$file}->{open} );
+		$pending->{$file}->{path} = $path;
+		$pending->{$file}->{open} = 0;	# not really opened, just uncompressed
+		warn "## tmp_file( $file ) $op $path [", -s $path, "]\n" if $debug;
 	}
-	warn "## create_temp_file( $file ) => $path [", -s $path, "]\n";
 	return $path;
 }
 
-sub compress_path_dest {
-	my ( $path, $dest ) = @_;
+sub compress_file2path {
+	my ( $file, $path ) = @_;
+
+	my $dest = fixup( $file );
+
+	if ( defined($pending->{$file}) ) {
+		my $pending_path = $pending->{$file}->{path} || confess "no path for $file in ",dump( $pending );
+
+		if ( $pending->{$file}->{open} > 1 ) {
+			warn "$file used ", $pending->{$file}->{open}, " times, delaying compression\n";
+			return;
+		} elsif ( ! $path ) {
+			$path = $pending_path;
+		} elsif ( $pending_path ne $path ) {
+			confess "ASSERT: compressing into $path instead of $pending_path";
+		}
+	}
+
+	confess "need path" unless $path;
 
 	# cleanup old compressed copy
 	if ( $dest =~ /\.gz$/ ) {
 		warn "## remove old $dest\n";
 		unlink $dest || confess "can't remove $dest: $!";
 		$dest =~ s/\.gz$//;
+		confess "ASSERT: uncompressed $dest shouldn't exist!" if -e $dest;
 	}
 
 	if ( $path =~ $skip_extensions_regex ) {
@@ -169,13 +210,21 @@
 		my ( $size_path, $size_comp ) = ( -s $path, -s $comp );
 
 		if ( $size_path <= $size_comp ) {
-			warn ">>> $size_path <= $size_comp leaving uncompressed\n";
+			warn ">>> $size_path <= $size_comp leaving uncompressed $dest\n";
 			unlink $comp || confess "can't remove: $comp: $!";
+			file_copy( '<', $path, '>', $dest ) if ( $path ne $dest );
 		} else {
-			warn ">>> compressed $size_path -> $size_comp ",int(($size_comp * 100) / $size_path),"%\n";
+			warn ">>> compressed $size_path -> $size_comp ",int(($size_comp * 100) / $size_path),"% $comp\n";
+
 			# FIXME add timeout to remove uncompressed version?
 			unlink $path || confess "can't remove $path: $!";
+
+			if ( -e $dest ) {
+				warn "## cleanup uncompressed $dest\n" if $debug;
+				unlink $dest || confess "can't remove $dest: $!";
+			}
 		}
+
 	}
 }
 
@@ -194,8 +243,6 @@
 		return 0;
 	}
 
-	$pending->{$file}->{open}++;
-
 	my $mode_desc = {
 		rdonly => $mode && O_RDONLY,
 		rdwr => $mode && O_RDWR,
@@ -204,22 +251,32 @@
 		trunc => $mode && O_TRUNC,
 	};
 
-	my $path = create_tmp_file( $file );
+	my $path = tmp_path( $file );
 
 	warn "## open( $file, $mode ) pending: ", $pending->{$file}->{open}, " mode $mode: ", dump( $mode_desc )," $path [", -s $path, "]\n" if $debug;
 
 	my $fh;
+	my $rv = 0;
+
+	if ( ! -w $path ) {
+		my $old_mode = (stat $path)[2];
+		my $new_mode = $old_mode | 0600;
+		chmod $new_mode, $path || confess "can't chmod $new_mode $path";
+		warn "### modify mode $old_mode -> $new_mode for $path\n";
+		$pending->{$file}->{mode} = $old_mode;
+	}
 
 	if ( sysopen($fh , $path, $mode) ) {
 		close($fh) || confess "can't close $path: $!";
-		warn "<<< open $path [", -e $path ? -s $path : 'new' , "]\n";
-		$pending->{$file}->{path} = $path;
-		return 0;
+		warn "<<< sysopen $path [", -e $path ? -s $path : 'new' , "]\n";
+		$pending->{$file}->{open}++;
 	} else {
 		warn "ERROR: can't open $path -- $!";
-		return -$!;
+		$rv = -$!;
 	}
 
+	return $rv;
+
 }
 
 sub x_read {
@@ -236,6 +293,7 @@
 
 	if(seek($fh,$off,SEEK_SET)) {
 		read($fh,$rv,$bufsize);
+		$pending->{$file}->{read} += length($rv) if $stats;
 	}
 
 	return $rv;
@@ -252,14 +310,15 @@
 	return -ENOENT() unless -e $path;
 
 	$path = $pending->{$file}->{path} || confess "no path for $file in ", dump( $pending );
-	confess "write into non-existant $path for $file: $!" unless -e $path;
+	confess "write into non-existant $path for $file" unless -e $path;
 
 	my $fh = new IO::File;
 	return -ENOSYS() unless open($fh,'+<',$path);
 	if($rv = seek( $fh ,$off,SEEK_SET)) {
 		$rv = print( $fh $buf );
-		warn "## write $path offset $off [",length( $buf ), "]\n" if $debug;
-		$pending->{$file}->{write}++;
+		my $size = length($buf);
+		warn "## write $path offset $off [$size]\n" if $debug;
+		$pending->{$file}->{write} += $size;
 	}
 	$rv = -ENOSYS() unless $rv;
 	close($fh) || warn "can't close $path: $!";
@@ -299,8 +358,8 @@
 	warn "# symlink( $from_path -> $to_path ) = $rv\n" if $debug;
 
 	my $tmp = $mount->{tmp} . '/' . $from;
-	if ( -e $tmp ) {
-		my $tmp_to = $mount->{$tmp} . '/' . $to;
+	my $tmp_to = $mount->{tmp} . '/' . $to;
+	if ( $rv == 0 && -e $tmp_to ) {
 		symlink( $tmp, $tmp_to ) || confess "can't symlink $tmp -> $tmp_to: $!";
 	}
 	return $rv;
@@ -332,7 +391,7 @@
 	my $tmp = $mount->{tmp} . '/' . $old;
 	if ( -e $tmp ) {
 		if ( $new =~ m#\Q/.fuse_hidden\E# ) {
-			unlink $tmp || confess "can't unlink $tmp for $new\n";
+			unlink $tmp || confess "can't unlink $tmp for $new";
 		} else {
 			my $new_tmp = $mount->{tmp} . '/' . $new;
 			rename $tmp, $new_tmp || confess "can't rename $tmp -> $new_tmp : $!";
@@ -381,17 +440,10 @@
 
 	#confess "no pending file $file to truncate in ", dump( $pending ) unless defined( $pending->{$file} );
 
-	my $path;
-
-	if (defined( $pending->{$file} )) {
-		$pending->{$file}->{write}++;
-		$path = fixup( $file );
-	} else {
-		$path = create_tmp_file( $file );
-		compress_path_dest( $path, fixup( $file ) );
-	}
+	my $path = tmp_path( $file );
 	my $rv = truncate( $path, $size ) ? 0 : -$! ;
 	warn "## truncate( $file $size ) $path [", -s $path, "] = $rv\n" if $debug;
+	compress_file2path( $file, $path );
 
 	return $rv;
 }
@@ -414,30 +466,32 @@
 sub x_release {
 	my ( $file, $mode ) = @_;
 
-	if ( $file =~ m#\Q/.fuse_hidden\E# ) {
-		warn "release internal $file\n" if $debug;
-		delete( $pending->{$file} );
-		return 0;
-	}
-
 	if ( ! defined( $pending->{$file} ) ) {
 		warn "release $file, NO PENDING DATA\n";
 		return 0;
 	} elsif ( ! defined( $pending->{$file}->{write} ) ) {
 		warn "release $file, not written into\n";
-	} elsif ( defined( $pending->{$file}->{open} ) && $pending->{$file}->{open} == 1 ) {
-		my $path = $pending->{$file}->{path} || confess "no path for $file ? ", dump( $pending );
-		my $dest = fixup( $file );
-		compress_path_dest( $path, $dest );
-
+	} elsif ( $file =~ m#\Q/.fuse_hidden\E# ) {
+		warn "release internal $file\n" if $debug;
 	} else {
-		warn "release $file, but still used ", $pending->{$file}->{open} , " times, delaying compression\n";
+		compress_file2path( $file );
 	}
+
 	$pending->{$file}->{open}--;
 	if ( $pending->{$file}->{open} == 0 ) {
-		warn "## cleanup pending $file [", -s fixup($file), "]\n" if $debug;
+
+		my $path = fixup( $file );
+
+		if ( my $old_mode = $pending->{$file}->{mode} ) {
+			chmod $old_mode, $path || confess "can't chmod $old_mode $path";
+			warn "### restored mode $old_mode $path\n";
+
+		}
+
+		warn "## cleanup pending $file [", -s $path, "]\n" if $debug;
 		delete( $pending->{$file} );
 	}
+
 	return 0;
 }