Patch backuppc to not keep /var/lib/backuppc/LOG open permanently

Because I want to be able to automount /var/lib/backuppc to allow its
disks to spin down when not backing up, I need to not keep the one LOG
file open that it keeps open.  So as to not be too intrusive into the
backuppc code and rewrite every LOG caller, I just fork off a loop
that open-appends/writes/closes the file on demand.

(also backupppc machine needs to know how to turn on the backup backup
server, so remember to keep that file in sync with our repo now that
we've removed it from CVS control)

Author: spacelama

files/usr/share/backuppc/bin/BackupPC.patch

@@ -0,0 +1,78 @@
+--- BackupPC.debian	2023-01-15 21:24:36.000000000 +1100
++++ BackupPC	2025-05-07 02:12:00.000000000 +1000
+@@ -66,7 +66,7 @@
+ use Carp;
+ use version;
+ use Digest::MD5;
+-use POSIX qw(setsid);
++use POSIX qw(setsid dup2);
+ 
+ ###########################################################################
+ # Handle command line options
+@@ -2011,14 +2011,41 @@
+     }
+ }
+ 
+-#
+-# Open the log file and point STDOUT and STDERR there too
++######################################################################
++# Modification fromdebian backuppc 4.4.0-8 20250507 tconnors to not
++# hold the master LOG file open perpetually - only open to append when
++# writing each line
++
++# Open the log file and point STDOUT and STDERR there too - but
++# lazily.  We fork a child, and they open the file for append only
++# when there's a line ready to be written.
+ #
+ sub LogFileOpen
+ {
+     mkpath($LogDir, 0, 0777) if ( !-d $LogDir );
+-    open(LOG, ">>$LogDir/LOG")
+-      || die("Can't create LOG file $LogDir/LOG");
++
++    pipe(my $reader, my $writer) or die "pipe failed: $!";
++
++    my $pid = fork();
++    die "fork failed: $!" unless defined $pid;
++
++    if ($pid == 0) {
++        # Child
++        close $writer; # Child reads
++        open(STDIN, "<&", $reader) or die "dup stdin failed: $!";
++        close $reader;
++
++        # Replace this with your custom log processor function
++        run_log_handler();
++
++        exit 0;
++    }
++
++    # Parent
++    close $reader; # Parent writes
++    open(LOG, ">&", $writer) or die "dup log failed: $!";
++    close $writer; # LOG has it now
++
+     close(STDOUT);
+     close(STDERR);
+     open(STDOUT, ">&LOG");
+@@ -2028,6 +2055,20 @@
+     select(STDOUT); $| = 1;
+ }
+ 
++# the log file child handler
++sub run_log_handler {
++    # Example: Just dump everything from STDIN to a file or process it
++    while (<STDIN>) {
++        open(LOG, ">>$LogDir/LOG")
++          || die("Can't create LOG file $LogDir/LOG");
++        print LOG "$_";
++        close(LOG) || die("Can't close LOG file $LogDir/LOG");
++    }
++}
++
++######################################################################
++
++
+ #
+ # Initialize the unix-domain and internet-domain sockets that
+ # we listen to for client connections (from the CGI script and

hosts.yml

@@ -214,6 +214,13 @@ all:
             ZFS_SHARE: "no"
             ZFS_UNSHARE: "no"
             DO_OVERLAY_MOUNTS: "yes"
+          custom_files:
+            - name: /usr/local/bin/turn-on-pve-backup
+              source: management/turn-on-pve-backup
+            - name: /usr/local/bin/turn-off-pve-backup
+              source: management/turn-off-pve-backup
+            - name: /usr/share/backuppc/bin/BackupPC
+              source: usr/share/backuppc/bin/BackupPC.patch
         iot:
           host_is_virtual: true
           # host_has_backports: true

roles/install_files/tasks/install_dir_file_or_template.yml

@@ -29,6 +29,7 @@
 - name: Include install file
   include_tasks: install_file.yml
   when: ( source is not regex(".*\\.j2$") ) and
+        ( source is not regex(".*\\.patch") ) and
         ( source is not regex(".*/$") ) and
         ( not (
           ( ( dir_file_or_template.type | default("file")) == "symlink" ) and
@@ -46,3 +47,7 @@
   when: ( source is regex(".*\\.j2$") )
         # implied can't also be directory
 
+- name: Include install patch
+  include_tasks: install_patch.yml
+  when: ( source is regex(".*\\.patch$") )
+        # implied can't also be directory

roles/install_files/tasks/install_patch.yml

@@ -0,0 +1,9 @@
+---
+# generates a file .name, from patch .source.patch
+
+- name: "install patch per diff: '{{ dir_file_or_template.name }}' from '{{ source }}'"
+  patch:
+    dest: "{{ dir_file_or_template.name | default(('/' ~ dir_file_or_template) | regex_replace('\\.patch$', '')) }}"
+    src: "{{ source }}"
+  become: "{{ dir_file_or_template.become | default(true) }}"
+  notify: "{{ dir_file_or_template.notify | default(omit) }}"

roles/install_user_files/tasks/install_user_dir_file_or_template.yml

@@ -29,6 +29,7 @@
 - name: Include install user file
   include_tasks: install_user_file.yml
   when: ( source is not regex(".*\\.j2$") ) and
+        ( source is not regex(".*\\.patch$") ) and
         ( source is not regex(".*/$") )
 # unlike install_dir_file_or_template, we resolve the symlink locally
 # in all cases, because half the time they refer back to something on
@@ -39,3 +40,7 @@
   when: ( source is regex(".*\\.j2$") )
         # implied can't also be directory
 
+- name: Include install user patch
+  include_tasks: install_user_patch.yml
+  when: ( source is regex(".*\\.patch$") )
+        # implied can't also be directory

roles/install_user_files/tasks/install_user_patch.yml

@@ -0,0 +1,9 @@
+---
+# generates a file .name, from patch .source.patch
+
+- name: "install user patch per diff: ~{{ user }}/'{{ dir_file_or_template.name }}' from '{{ source }}'"
+  template:
+    dest: "~{{ user }}/{{ dir_file_or_template.name }}"
+    src: "{{ source }}"
+  become: true
+  become_user: "{{ user }}"