added submodules of new Lock.pm

[selfforum.git] / selfforum-cgi / shared / Lock / Unlink.pm

diff --git a/selfforum-cgi/shared/Lock/Unlink.pm b/selfforum-cgi/shared/Lock/Unlink.pm
new file mode 100644 (file)
index 0000000..d7bd6ec
--- /dev/null
+++ b/selfforum-cgi/shared/Lock/Unlink.pm
@@ -0,0 +1,124 @@
+package Lock::Unlink;
+
+################################################################################
+#                                                                              #
+# File:        shared/Lock/Unlink.pm                                           #
+#                                                                              #
+# Authors:     Andre Malo       <nd@o3media.de>, 2001-05-25                    #
+#                                                                              #
+# Description: Locking and Filehandle class                                    #
+#              using the atomic behavior of unlinkig files                     #
+#                                                                              #
+################################################################################
+
+use strict;
+use vars qw(
+  $VERSION
+);
+
+use Fcntl;
+
+################################################################################
+#
+# Version check
+#
+$VERSION = do { my @r =(q$Revision$ =~ /\d+/g); sprintf "%d."."%02d" x $#r, @r };
+
+### sub _simple_lock ###########################################################
+#
+# simple file lock
+# (unlink lock file)
+#
+# Params: $filename - file to lock
+#         $timeout  - timeout
+#
+# Return: success (boolean)
+#
+sub _simple_lock {
+  my ($self, $fh) = @_;
+
+  unlink $fh -> filename and return 1;
+
+  return;
+}
+
+### sub _simple_unlock #########################################################
+#
+# simple file unlock
+# (create lock file)
+#
+# Params: $filename - lockfile name
+#                     ^^^^^^^^
+#
+# Return: success (boolean)
+#
+sub _simple_unlock {
+  my ($self, $filename) = @_;
+  local *LF;
+
+  sysopen (LF, $filename, O_WRONLY | O_CREAT | O_TRUNC)
+    and close LF
+    and return 1;
+
+  # not able to create lock file, hmmm...
+  #
+  return;
+}
+
+### sub _reftime ###############################################################
+#
+# determine reference time for violent unlock
+#
+# Params: ~none~
+#
+# Return: time or zero, if no reference file found
+#
+sub _reftime {
+  my $self = shift;
+  my ($time, $reffile) = 0;
+
+  if (-f ($reffile = $self -> filename)) {
+    $time = (stat $reffile)[9];}
+
+  elsif (-f ($reffile = $self -> lockfile)) {
+    $time = (stat $reffile)[9];}
+
+  $time;
+}
+
+### sub masterlocked ###########################################################
+#
+# check on master lock status of the file
+#
+# Params: ~none~
+#
+# Return: status (boolean)
+#
+sub masterlocked {not -f shift -> masterlock}
+
+### sub excl_announced #########################################################
+#
+# check on exclusive lock announced status of the file
+#
+# Params: ~none~
+#
+# Return: status (boolean)
+#
+sub excl_announced {not -f shift -> lockfile}
+
+### sub exsh_announced #########################################################
+#
+# check on exclusive shared lock status of the file
+#
+# Params: ~none~
+#
+# Return: status (boolean)
+#
+sub exsh_announced {not -f shift -> exshlock}
+
+# keep 'require' happy
+1;
+
+#
+#
+### end of Lock::Unlink ########################################################