--- syncmail/folder.pm	2001/10/28 04:00:58	1.3
+++ syncmail/folder.pm	2001/10/28 20:52:24	1.4
@@ -2,17 +2,61 @@
 
 BEGIN { *slog = \&::slog };
 
-use Digest::SHA1;
+use Fcntl;
+use File::Sync ();
+
+use Inline Config => NAME => "syncmail::folder";
+use Inline C;
 
 use constant MDIFVERSION => 1;
 
+BEGIN {
+   if (1) {
+      use OpenSSL ();
+      *hash = \&OpenSSL::Digest::sha1_hex;
+   } elsif (0) {
+      # use Digest::SHA1 ();
+      my $digest = new Digest::SHA1;
+      *hash = sub {
+         $digest->reset;
+         $digest->add(@_);
+         $mid = $digest->hexdigest;
+      };
+   } 
+}
+
+sub flushfh {
+   my $oldfh = select $_[0];
+   $| = 1;
+   select $oldfh;
+}
+
+# rename a file and fsync the directory
+sub replace {
+   my ($src, $dst) = @_;
+   my $self = shift;
+
+   rename $src, $dst;
+
+   $dst =~ s/[^\/]*$/./;
+
+   # now sync the directory
+
+   open my $dir, "<", $dst
+      or die "$dst: $!";
+
+   File::Sync::fsync($dir);
+}
+
 sub new {
    my $class = shift;
    my %arg = @_;
-   bless {
+   my $self = bless {
       path => "$::PREFIX/$arg{name}",
       %arg,
    }, $class;
+   $self->open(0);
+   $self;
 }
 
 sub dirty {
@@ -28,19 +72,15 @@
 # $header includes the mbox From_ line without
 # the leading From_ itself.
 sub parse_mbox {
-  my ($path, $cb) = @_;
-
-  open my $fh, "<", $path
-     or die "$path: $!";
+  my ($fh, $cb) = @_;
 
   local $/ = "\n\n";
 
   my ($head, $body, $offs);
 
-  5 == read $fh, $head, 5
-     or return;
+  read $fh, $head, 5;
 
-  $head eq "From "
+  $head eq "From " or $head eq ""
      or return;
 
   $offs = 0;
@@ -59,7 +99,7 @@
      chomp $body;
      $cb->($offs, \$head, \$body);
      $offs = (tell $fh) - 5;
-     ::give unless ++$ecnt & 1023;
+     &::give unless ++$ecnt & 255;
   }
 
   1;
@@ -152,29 +192,18 @@
       print $fh "-$_\n" for @{$_->[2]};
    }
 
+   flushfh $fh;
+   File::Sync::fsync($fh);
    close $fh
       or die "$path~: unable to create updated .mdif: $!";
 
-   rename "$path~", $path;
+   replace("$path~", $path);
 
    delete $self->{dirty};
 }
 
-if (1) {
-   use OpenSSL ();
-   *hash = \&OpenSSL::Digest::sha1_hex;
-} elsif (0) {
-   # use Digest::SHA1;
-   my $digest = new Digest::SHA1;
-   *hash = sub {
-      $digest->reset;
-      $digest->add(@_);
-      $mid = $digest->hexdigest;
-   };
-} 
-
 sub gendiff {
-   my ($d1, $d2) = @_;
+   my ($self, $d1, $d2) = @_;
 
    my (@add, @del);
    my (%d1, %d2);
@@ -195,7 +224,10 @@
       push @add, $_->[1] unless exists $d1{$_->[1]};
    }
 
-   (\@add, \@del);
+   push @{$self->{diff}}, [
+      $self->{ctime},
+      \@add, \@del,
+   ] if @add || @del;
 }
 
 sub check {
@@ -206,57 +238,164 @@
 
    slog 3, "checking $path\n";
 
-   if (stat $path) {
-      my ($fsize, $mtime) = (stat _)[7, 9];
+   stat $path
+      or die "$path: $!";
 
-      if (open my $fh, "<", $conf) {
-         my %conf;
-         <$fh>; # skip initial comment
-         <$fh> eq "[SYNCMAIL]\n"
-            or die "$conf: format error";
-         while (<$fh> =~ /^([a-z]+)\s*=\s*(.*)$/) {
-            $conf{$1} = $2;
-         }
-         return 1 if $fsize == $conf{fsize}
-                  && $mtime == $conf{mtime};
+   my ($fsize, $mtime) = (stat _)[7, 9];
 
-         $conf{mtime} <= $mtime
-            or die "$path: folder older than mdif";
+   if (open my $fh, "<", $conf) {
+      my %conf;
+      <$fh>; # skip initial comment
+      <$fh> eq "[SYNCMAIL]\n"
+         or die "$conf: format error";
+      while (<$fh> =~ /^([a-z]+)\s*=\s*(.*)$/) {
+         $conf{$1} = $2;
       }
+      return 1 if $fsize == $conf{fsize}
+               && $mtime == $conf{mtime};
+
+      $conf{mtime} <= $mtime
+         or die "$path: folder older than mdif";
+   }
+
+   slog 2, "updating $path\n";
 
-      slog 2, "updating $path\n";
+   my @idx;
 
-      my @idx;
+   parse_mbox $self->{fh}, sub {
+      my ($offs, $head, $body) = @_;
+      push @idx, [$offs, hash($$head, "\0", $$body)];
+   } or die "$path: no valid mbox file";
 
-      parse_mbox $path, sub {
-         my ($offs, $head, $body) = @_;
-         push @idx, [$offs, hash($$head, "\0", $$body)];
-      } or return ();
+   $self->read_mdif;
 
-      $self->read_mdif;
+   $self->{version} ||= MDIFVERSION;
+   $self->{ctime} = time;
 
-      $self->{version} ||= MDIFVERSION;
-      $self->{fsize} = $fsize;
-      $self->{mtime} = $mtime;
-      $self->{ctime} = time;
-      $self->{idx}   = \@idx;
+   $self->gendiff($self->{idx}, \@idx);
 
-      my ($add, $del) = gendiff $self->{idx}, \@idx;
-      push @{$self->{diff}}, [
-         $self->{ctime},
-         $add, $del,
-      ] if @$add || @$del;
+   $self->{fsize} = $fsize;
+   $self->{mtime} = $mtime;
+   $self->{idx}   = \@idx;
+
+   $self->dirty;
+   $self->write_mdif;
+}
+
+sub inventory {
+   hash sort map { $_->[1] } @{$_[0]{idx}};
+}
 
-      $self->dirty;
+sub open {
+   my ($self, $rw) = @_;
 
-      return 2;
-   } else {
-      slog 2, "$path: no longer exists\n";
-      unlink $conf;
+   if (!$self->{fh} || $self->{rw} != $rw) {
+      $self->close;
+      $self->{rw} = $rw;
+      sysopen $self->{fh}, $self->{path},
+              O_CREAT | ($rw ? O_RDWR : O_RDONLY),
+              0666
+         or die "$self->{path}: $!";
+      0 == setlkw(fileno $self->{fh}, $rw ? 2 : 1)
+         or die "$self->{path}: $!";
 
-      return ();
    }
 }
 
+sub close {
+   my $self = shift;
+
+   flushfh $self->{fh};
+   File::Sync::fsync($self->{fh});
+   delete $self->{fh};
+}
+
+# begin updating folder
+sub begin_update {
+   my $self = shift;
+
+   $self->{oidx} = $self->{idx};
+
+}
+
+sub delete {
+   my $self = shift;
+   my $temp = "$self->{path}~";
+
+   if (@_) {
+      my $guard = $::lockdisk->guard;
+      my %del; @del{@_} = ();
+
+      open my $fh, ">", $temp
+         or die "$temp: $!";
+
+      my $nidx;
+      my $idx = delete $self->{idx};
+      push @$idx, [$self->{fsize}];
+      $self->{fsize} = 0; # we virtually truncated the file
+
+      slog 0, "XXXXXXXXXXXXXXX @_\n";#d#
+
+      my $ofs = 0;
+      for (0 .. @$idx - 2) {
+         my $buf;
+
+         unless (exists $del{$idx->[$_][1]}) {
+            my $len = $idx->[$_+1][0] - $idx->[$_][0];
+
+            slog 0, "$idx->[$_][1] $idx->[$_+1][0] - $idx->[$_][0]\n";#d#
+
+            seek $self->{fh}, $idx->[$_][0],SEEK_SET
+               or die "$self->{path}: $!";
+
+            $len == read $self->{fh}, $buf, $len
+               or die "$self->{path}: $!";
+
+            $buf =~ /^From \S/
+               or die "$self->{path}: corrupted mail folder";
+
+            &::give unless ++$ecnt & 255;
+         } else {
+            slog 0, "skipping $idx->[$_][1]\n";
+         }
+      }
+
+      File::Sync::fsync($fh);
+      close $fh;
+
+      # replace $temp, $self->{path}
+   }
+}
+
+sub end_update {
+}
+
+sub append {
+   my $self = shift;
+
+   &update;
+   #$self->open(1);
+}
+
 1;
 
+__DATA__
+__C__
+#include <unistd.h>
+#include <fcntl.h>
+
+/* mode0 unlock, mode1 rlock, mode2 rwlock */
+int setlkw(int fd, int mode)
+{
+   struct flock l;
+
+   l.l_type   = mode == 0 ? F_UNLCK
+              : mode == 1 ? F_RDLCK
+              :             F_WRLCK;
+   l.l_whence = SEEK_SET;
+   l.l_start  = 0;
+   l.l_len    = 0;
+
+   return fcntl (fd, F_SETLKW, &l);
+}
+