--- loncom/debugging_tools/modify_config_files.pl	2011/05/31 02:55:15	1.12
+++ loncom/debugging_tools/modify_config_files.pl	2024/07/31 03:39:20	1.29
@@ -2,7 +2,7 @@
 #
 # The LearningOnline Network
 #
-# $Id: modify_config_files.pl,v 1.12 2011/05/31 02:55:15 raeburn Exp $
+# $Id: modify_config_files.pl,v 1.29 2024/07/31 03:39:20 raeburn Exp $
 #
 # Copyright Michigan State University Board of Trustees
 #
@@ -36,21 +36,42 @@ B<modify_config_files.pl>
 
 =head1 SYNOPSIS
 
-This script modifies /etc/my.cnf and one of: /etc/yum.conf 
-(for Fedora/CentOS/Scientific Linux/RHEL5), /etc/apt/sources.list
-(for Debian/Ubuntu) and /etc/sysconfig/rhn/sources (for RHEL4). 
+This script modifies local MySQL configuration file(s), which will be:
+/home/www/.my.cnf and, depending on distro/version also one of:
+/etc/my.cnf, /etc/mysql/my.cnf, /etc/mysql/mysql.conf.d/mysqld.cnf,
+or /etc/mysql/mariadb.conf.d/50-server.cnf, and also the file used to 
+store information about the LON-CAPA package repositories located at
+install.loncapa.org. which provide rpm or deb packages created for the  
+Linux distro/version being used.  The file to modify will be one of:
+/etc/yum.conf (for CentOS/Scientific Linux/RHEL >=5 and <8), 
+/etc/apt/sources.list (for Debian < 10 and Ubuntu < 22), or
+/etc/apt/sources.list.d/loncapa.list (for Debian >= 10 and Ubuntu > 20),
+/etc/sysconfig/rhn/sources (for RHEL4), or /etc/yum.repos.d/loncapa.repo
+(for Fedora >= 21; Oracle Linux; AlmaLinux; RockyLinux; CentOS/RHEL >= 8).
+
+The script also modifies /home/www/.inputrc on Linux distros which have 
+readline 8.1 or newer, i.e., CentOS/Scientific Linux/RHEL >= 9,
+Ubuntu >= 22, Debian >= 12, and Fedora >= 34.
 
 =head1 DESCRIPTION
 
-This script modifies /etc/my.cnf and /etc/yum.conf or /etc/apt/sources
-or /etc/sysconfig/rhn/sources to ensure certain parameters are set
-properly.  The LON-CAPA yum repositories are added to /etc/yum.conf or
-/etc/sysconfig/rhn/sources and the LON-CAPA apt repositories are added to 
-/etc/apt/sources.list.
-
-The /etc/my.cnf file is modified to set the wait_timeout to 1 year.  Backup
-copies of each file are made in /etc, /etc/apt, and /etc/sysconfig/rhn, as 
-appropriate.
+This script will modify /etc/my.cnf, /etc/mysql/my.cnf, 
+/etc/mysql/mysql.conf.d/mysqld.cnf, or
+/etc/mysql/mariadb.conf.d/50-server.cnf,
+and /etc/yum.conf, /etc/yum.repos.d/loncapa.repo,
+/etc/apt/sources.list, /etc/apt/sources.list.d/loncapa.list or 
+/etc/sysconfig/rhn/sources and /home/www/.inputrc to ensure 
+certain parameters are set properly.
+
+The LON-CAPA yum repositories are added to /etc/yum.conf, 
+/etc/yum.repos.d/loncapa.repo, or /etc/sysconfig/rhn/sources
+and the LON-CAPA apt repositories are added to 
+/etc/apt/sources.list or /etc/apt/sources.list.d/loncapa.list.
+
+The /etc/my.cnf, /etc/mysql/my.cnf /etc/mysql/mysql.conf.d/mysqld.cnf
+or /etc/mysql/mariadb.conf.d/50-server.cnf file is modified to set the 
+wait_timeout to 1 year.  Backup copies of each file are made in
+/etc, /etc/apt, and /etc/sysconfig/rhn, as appropriate.
 
 =cut
 
@@ -69,14 +90,20 @@ my $yum_status;
 my $loninst = 'http://install.loncapa.org';
 my $loninst_re = 'http://install\.loncapa\.org';
 if ($dist =~ /^fedora(\d+)$/) {
+    my $file = '/etc/yum.conf';
     my $ver = $1;
     my $gpgchk = '0';
     my $gpg = "$loninst/versions/fedora/RPM-GPG-KEY-loncapa"; 
+    my $nobackup;
     if ($ver > 6) {
         $gpgchk = '1';
     }
+    if ($ver >= 21) {
+        $file = '/etc/yum.repos.d/loncapa.repo';
+        $nobackup = 1;
+    }
     $yum_status =  
-        &update_file('/etc/yum.conf',
+        &update_file($file,
              [{section => 'loncapa-updates-basearch',
                key     => 'name=',
                value   => 'Fedora Core $releasever LON-CAPA $basearch Updates',
@@ -87,7 +114,7 @@ if ($dist =~ /^fedora(\d+)$/) {
                key     => 'gpgcheck=',
                value   =>  $gpgchk,
            }, {section => 'loncapa-updates-basearch',
-               key     => 'gpg=',
+               key     => 'gpgkey=',
                value   => $gpg,
            }, {section => 'loncapa-updates-noarch',
                key     => 'name=',
@@ -99,19 +126,23 @@ if ($dist =~ /^fedora(\d+)$/) {
                key     => 'gpgcheck=',
                value   => $gpgchk,
            }, {section => 'loncapa-updates-noarch',
-               key     => 'gpg=',
+               key     => 'gpgkey=',
                value   => $gpg,
-           }]);
-} elsif ($dist =~ /^(rhes|centos|scientific)(\d+)$/) {
+           }],$nobackup);
+} elsif ($dist =~ /^(rhes|centos|scientific|oracle|rocky|alma)(\d+)(|\-stream)$/) {
     my $type = $1;
     my $ver = $2;
+    my $stream = $3;
     my $longver = $ver;
+    my $nobackup;
     if ($type eq 'rhes') {
         if ($ver == 4) {
             $longver = '4ES';
         } elsif ($ver == 5) {
             $longver = '5Server';
         }
+    } elsif ($type eq 'centos') {
+        $type .= $stream;
     }
     my %info = (
                  rhes => {
@@ -132,17 +163,51 @@ if ($dist =~ /^fedora(\d+)$/) {
                                  gpg => 'versions/scientific/RPM-GPG-KEY-loncapa',
                                  gpgchk => 1,
                                },
+                 oracle => {
+                             title => 'Oracle Linux',
+                             path => 'oracle/loncapa',
+                             gpg => 'versions/oracle/RPM-GPG-KEY-loncapa',
+                             gpgchk => 1,
+                           },
+                 rocky => {
+                             title => 'Rocky Linux',
+                             path => 'rocky/loncapa',
+                             gpg => 'versions/rocky/RPM-GPG-KEY-loncapa',
+                             gpgchk => 1,
+                          },
+                 alma => {
+                             title => 'AlmaLinux',
+                             path => 'alma/loncapa',
+                             gpg => 'versions/alma/RPM-GPG-KEY-loncapa',
+                             gpgchk => 1,
+                          },
+                 'centos-stream' => {
+                                      title => 'CentOS Stream',
+                                      path  => 'centos/loncapa',
+                                      gpg => 'versions/centos/RPM-GPG-KEY-loncapa',
+                                      gpgchk => 1, 
+                                    },
                );
     if (ref($info{$type}) eq 'HASH') {
         if ($ver > 4) {
+            my $file = '/etc/yum.conf';
+            if (($ver > 7) || ($type eq 'oracle') || ($type eq 'rocky') || 
+                ($type eq 'alma') || ($type eq 'centos-stream')) {
+                $file = '/etc/yum.repos.d/loncapa.repo';
+                $nobackup = 1;
+            }
+            my $release = '$releasever';
+            if ($type eq 'centos-stream') {
+                $release .= '-stream';
+            }
             $yum_status =
-                &update_file('/etc/yum.conf',
+                &update_file($file,
                      [{section => 'loncapa-updates-basearch',
                        key     => 'name=',
                        value   => $info{$type}{title}.' $releasever LON-CAPA $basearch Updates',
                       }, {section => "loncapa-updates-basearch",
                           key     => 'baseurl=',
-                          value   => "$loninst/$info{$type}{path}/".'$releasever/$basearch',
+                          value   => "$loninst/$info{$type}{path}/$release/".'$basearch',
                       }, {section => 'loncapa-updates-basearch',
                           key     => 'gpgcheck=',
                           value   => $info{$type}{gpgchk},
@@ -154,14 +219,14 @@ if ($dist =~ /^fedora(\d+)$/) {
                           value   => $info{$type}{title}.' $releasever LON-CAPA noarch Updates',
                       }, {section => 'loncapa-updates-noarch',
                           key     => 'baseurl=',
-                          value   => "$loninst/$info{$type}{path}/".'$releasever/noarch',
+                          value   => "$loninst/$info{$type}{path}/$release/noarch",
                       }, {section => 'loncapa-updates-noarch',
                           key     => 'gpgcheck=',
                           value   => $info{$type}{gpgchk},
                       }, {section => 'loncapa-updates-noarch',
                           key     => 'gpgkey=',
                           value   => "$loninst/$info{$type}{gpg}",
-                      }]);
+                      }],$nobackup);
         } elsif (($type eq 'rhes') && ($ver == 4)) {
             my %rhn = (
                         basearch => { 
@@ -176,32 +241,114 @@ if ($dist =~ /^fedora(\d+)$/) {
             $yum_status = &update_rhn_source(\%rhn); 
         }
     }
-} elsif ($dist =~ /^(debian|ubuntu)\d+$/) {
+} elsif ($dist =~ /^(debian|ubuntu)(\d+)$/) {
+    my ($distname,$distver) = ($1,$2);
+    if ((($distname eq 'ubuntu') && ($distver > 20)) ||
+        (($distname eq 'debian') && ($distver >= 10))) {
+        $loninst = 'https://install.loncapa.org';
+        $loninst_re = 'https://install\.loncapa\.org';
+    }
     my %apt_get_source = (
                            debian5 => {
-                                        regexp => '\s*deb\s+'.$loninst_re.'/debian/\s+lenny\s+main',
-                                        text   => "deb $loninst/debian/ lenny main",
+                                        regexp => '\s*deb\s+'.$loninst_re.'/debian/?\s+lenny\s+main',
+                                        text   => "deb $loninst/debian lenny main",
+                                      },
+                           debian6 => {
+                                        regexp => '\s*deb\s+'.$loninst_re.'/debian/?\s+squeeze\s+main',
+                                        text   => "deb $loninst/debian squeeze main",
                                       },
+                           debian10 => {
+                                        regexp => '\s*deb\s+\[signed\-by=/etc/apt/keyrings/loncapa\.gpg\]\s+'.$loninst_re.'/debian/?\s+buster\s+main',
+                                        text   => "deb [signed-by=/etc/apt/keyrings/loncapa.gpg] $loninst/debian buster main",
+                                      },
+                           debian11 => {
+                                        regexp => '\s*deb\s+\[signed\-by=/etc/apt/keyrings/loncapa\.gpg\]\s+'.$loninst_re.'/debian/?\s+bullseye\s+main',
+                                        text   => "deb [signed-by=/etc/apt/keyrings/loncapa.gpg] $loninst/debian bullseye main",
+                                      },
+                           debian12 => {
+                                        regexp => '\s*deb\s+\[signed\-by=/etc/apt/keyrings/loncapa\.gpg\]\s+'.$loninst_re.'/debian/?\s+bookworm\s+main',
+                                        text   => "deb [signed-by=/etc/apt/keyrings/loncapa.gpg] $loninst/debian bookworm main",
+                                      },
+
                            ubuntu6 => {
-                                        regexp => '\s*deb\s+'.$loninst_re.'/ubuntu/\s+dapper\s+main',
-                                        text   => "deb $loninst/ubuntu/ dapper main",
+                                        regexp => '\s*deb\s+'.$loninst_re.'/ubuntu/?\s+dapper\s+main',
+                                        text   => "deb $loninst/ubuntu dapper main",
                                       },
                            ubuntu8 => {
-                                        regexp => '\s*deb\s+'.$loninst_re.'/ubuntu/\s+hardy\s+main',
-                                        text   => "deb $loninst/ubuntu/ hardy main",
+                                        regexp => '\s*deb\s+'.$loninst_re.'/ubuntu/?\s+hardy\s+main',
+                                        text   => "deb $loninst/ubuntu hardy main",
                                       },
+                           ubuntu10 => {
+                                        regexp => '\s*deb\s+'.$loninst_re.'/ubuntu/?\s+lucid\s+main',
+                                        text   => "deb $loninst/ubuntu lucid main",
+                                       },
+                           ubuntu12 => {
+                                        regexp => '\s*deb\s+'.$loninst_re.'/ubuntu/?\s+precise\s+main',
+                                        text   => "deb $loninst/ubuntu precise main",
+                                       },
+                           ubuntu14 => {
+                                        regexp => '\s*deb\s+'.$loninst_re.'/ubuntu/?\s+trusty\s+main',
+                                        text   => "deb $loninst/ubuntu trusty main",
+                                       },
+                           ubuntu16 => {
+                                        regexp => '\s*deb\s+'.$loninst_re.'/ubuntu/?\s+xenial\s+main',
+                                        text   => "deb $loninst/ubuntu xenial main",
+                                       },
+                           ubuntu18 => {
+                                        regexp => '\s*deb\s+'.$loninst_re.'/ubuntu/?\s+bionic\s+main',
+                                        text   => "deb $loninst/ubuntu bionic main",
+                                       },
+                           ubuntu20 => {
+                                        regexp => '\s*deb\s+'.$loninst_re.'/ubuntu/?\s+focal\s+main',
+                                        text   => "deb $loninst/ubuntu focal main",
+                                       },
+                           ubuntu22 => {
+                                        regexp => '\s*deb\s+\[signed\-by=/etc/apt/keyrings/loncapa\.gpg\]\s+'.$loninst_re.'/ubuntu/?\s+jammy\s+main',
+                                        text   => "deb [signed-by=/etc/apt/keyrings/loncapa.gpg] $loninst/ubuntu jammy main",
+                                       },
+                           ubuntu24 => {
+                                        regexp => '\s*deb\s+\[signed\-by=/etc/apt/keyrings/loncapa\.gpg\]\s+'.$loninst_re.'/ubuntu/?\s+noble\s+main',
+                                        text   => "deb [signed-by=/etc/apt/keyrings/loncapa.gpg] $loninst/ubuntu noble main",
+                                       },
                          );
     my $apt_status;
     if (defined($apt_get_source{$dist})) {
-        $apt_status = &update_apt_source($apt_get_source{$dist},);
+        $apt_status = &update_apt_source($distname,$distver,$apt_get_source{$dist});
+    }
+}
+
+my $mysqlfile = '/etc/my.cnf';
+my $mysqlconf = [{section =>'mysqld',
+                  key     =>'wait_timeout=',
+                  value   =>'31536000'}];
+my $nomysqlbackup;
+if ($dist =~ /^ubuntu(\d+)$/) {
+    my $version = $1;
+    $mysqlfile = '/etc/mysql/my.cnf';
+    if ($version > 14) {
+        $nomysqlbackup = 1;
+        $mysqlfile = '/etc/mysql/mysql.conf.d/mysqld.cnf';
+        if ($version < 20) {
+            push(@{$mysqlconf},
+                 {section =>'mysqld',
+                  key     =>'sql_mode=',
+                  value   =>'"STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_AUTO_CREATE_USER,NO_ENGINE_SUBSTITUTION"'});
+        } else {
+            push(@{$mysqlconf},
+                 {section =>'mysqld',
+                  key     =>'sql_mode=',
+                  value   =>'"STRICT_TRANS_TABLES,NO_ZERO_IN_DATE,NO_ZERO_DATE,ERROR_FOR_DIVISION_BY_ZERO,NO_ENGINE_SUBSTITUTION"'});
+        }
+    }
+} elsif ($dist =~ /^debian(\d+)$/) {
+    my $version = $1;
+    if ($version >= 10) {
+        $mysqlfile = '/etc/mysql/mariadb.conf.d/50-server.cnf';
+        $nomysqlbackup = 1;
     }
 }
 
-my $mysql_global_status =
-    &update_file('/etc/my.cnf',
-             [{section =>'mysqld',
-               key     =>'wait_timeout=',
-               value   =>'31536000', }]);
+my $mysql_global_status = &update_file($mysqlfile,$mysqlconf,$nomysqlbackup);
 
 my $local_my_cnf = '/home/www/.my.cnf';
 if (! -e $local_my_cnf) {
@@ -217,20 +364,177 @@ my $mysql_www_status =
                key     =>'password=',
                value   =>$loncapa_config->{'lonSqlAccess'}},]);
 
+my $needs_inputrc_check;
+if ($dist  =~ /^debian(\d+)$/) {
+    if ($1 >= 12) {
+        $needs_inputrc_check = 1;
+    }
+} elsif ($dist =~ /^ubuntu(\d+)$/) {
+    if ($1 >= 22) {
+        $needs_inputrc_check = 1;
+    }
+} elsif ($dist =~ /^(?:rhes|oracle|alma|rocky|centos)(\d+)(?:|\-stream)$/) {
+    if ($1 >= 9) {
+        $needs_inputrc_check = 1;
+    }
+} elsif ($dist =~ /^fedora(\d+)$/) {
+    if ($1 >= 34) {
+        $needs_inputrc_check = 1;
+    }
+}
+
+if ($needs_inputrc_check) {
+    my $bash_www_cnf = '/home/www/.inputrc';
+    if (!-e $bash_www_cnf) {
+        system("touch $bash_www_cnf");
+        if (open(my $fh,'>',$bash_www_cnf)) {
+            print $fh <<'END';
+$if R
+    set enable-bracketed-paste off
+$endif
+
+$if maxima
+    set enable-bracketed-paste off
+$endif
+END
+            close($fh);
+        } else {
+            warn "**** Error: could not open $bash_www_cnf to add 'set enable-bracketed-paste to off'";
+        }
+        my $wwwuid = getpwnam('www');
+        my $wwwgid = getgrnam('www');
+        if ($wwwuid!=$<) {
+            chown($wwwuid,$wwwgid,$bash_www_cnf);
+        }
+    } else {
+        my (%bracketed_paste_on,%bracketed_paste_off,@preserve,$condition);
+        $condition = '';
+        if (open(my $fh,'<',$bash_www_cnf)) {
+            while (my $line=<$fh>) {
+                chomp($line);
+                if ($line =~ /^\$if\s+(\w+)\s*$/) {
+                    if ($1 eq 'R') { 
+                        $condition = 'r';
+                    } elsif ($1 eq 'maxima') {
+                        $condition = 'maxima';
+                    } else {
+                        $condition = 'other';
+                    }
+                } elsif ($line =~ /^\$endif\s*$/) {
+                    $condition = '';
+                }
+                if ($line =~ /^\s*set\s+enable\-bracketed\-paste\s+(off|on)\s*$/) {
+                    if ($1 eq 'off') {
+                        if ($condition ne '') {
+                            $bracketed_paste_off{$condition} = 1;
+                        } else {
+                            $bracketed_paste_off{all} = 1;
+                        }
+                        push(@preserve,$line);
+                    } else {
+                        if ($condition ne '') {
+                            $bracketed_paste_on{$condition} = 1;
+                            if (($condition eq 'r') || ($condition eq 'maxima')) {
+                                push(@preserve,'    set enable-bracketed-paste off');
+                            } else {
+                                push(@preserve,$line); 
+                            }
+                        } else {
+                            $bracketed_paste_on{all} = 1;
+                            push(@preserve,$line);
+                        }
+                    }
+                } else {
+                    push(@preserve,$line);
+                }
+            }
+            close($fh);
+        }
+        if (($bracketed_paste_on{r} || $bracketed_paste_on{maxima}) ||
+            (!exists($bracketed_paste_off{r}) && !exists($bracketed_paste_on{r}) &&
+             !exists($bracketed_paste_off{maxima}) && !exists($bracketed_paste_on{maxima}))) {
+            if (open(my $fh,'>',$bash_www_cnf)) {
+                if (@preserve) {
+                    foreach my $entry (@preserve) {
+                        print $fh "$entry\n";
+                    }
+                    if (!exists($bracketed_paste_off{r}) && !exists($bracketed_paste_on{r})) {
+print $fh <<'END';
+$if R
+    set enable-bracketed-paste off
+$endif
+END
+                    }
+                    if (!exists($bracketed_paste_off{r}) && !exists($bracketed_paste_on{r})) {
+print $fh <<'END';
+$if maxima
+    set enable-bracketed-paste off
+$endif
+END
+                    }
+                } else {
+print $fh <<'END';
+$if R
+    set enable-bracketed-paste off
+$endif
+
+$if maxima
+    set enable-bracketed-paste off
+$endif
+END
+                }
+                close($fh);
+            } else {
+                warn "**** Error: could not open $bash_www_cnf to add 'set enable-bracketed-paste to off'";
+            }
+        }
+    }
+}
+
 my $exitvalue = 0;
 
 if ($mysql_global_status) { $exitvalue = 1; }
 
 exit $exitvalue;
 
+#################################################################
+#################################################################
+
+=pod
+
+=over 4
+
+=item &update_file()
+
+Calls &parse_config_file for a file and then sends the 
+retrieved data to &modify_config_file, and checks if
+modificatione were made.
+
+Inputs: filename, newdata (reference to an array of hashed),
+        nobackup 1, if no backup of existing file (.backup
+        appended to filename) should be made.
+
+Output: 0 or 1; o if no modifications exist (and hence no file
+needed to be saved, or 1 if modifications made, and call to
+&write_config_file to save file, or if filename does not exist.
+
+=back
+
+=cut
+
+#################################################################
+#################################################################
+
 
 sub update_file {
-    my ($file,$newdata) = @_;
+    my ($file,$newdata,$nobackup) = @_;
     return 1 if (! -e $file);
-    my $backup = $file.'.backup';
-    if (! copy($file,$backup)) {
-        warn "**** Error: Unable to make backup of $file";
-        return 0;
+    unless ($nobackup) {
+        my $backup = $file.'.backup';
+        if (! copy($file,$backup)) {
+            warn "**** Error: Unable to make backup of $file";
+            return 0;
+        }
     }
     my ($filedata) = &parse_config_file($file);
     if (! ref($filedata)) { warn "**** Error: $filedata"; return 0;}
@@ -306,7 +610,7 @@ sub parse_config_file {
 
 =over 4
 
-=item
+=item &write_config_file()
 
 Write a configuration file out based on the internal data structure returned
 by &parse_config_file
@@ -327,7 +631,7 @@ sub write_config_file {
     if (! defined($structure) || ! ref($structure)) {
         return 'Bad subroutine inputs';
     }
-    open(OUTPUT,'>'.$file) || return('Unable to open '.$file.' for writing');
+    open(OUTPUT,'>',$file) || return('Unable to open '.$file.' for writing');
     for (my $i=0;$i<scalar(@$structure);$i++) {
         my $line = $structure->[$i];
         chomp($line);
@@ -470,7 +774,7 @@ sub update_rhn_source {
     }
     my $result = 0;
     my $fh;
-    if (open($fh,"<$file")) {
+    if (open($fh,'<',$file)) {
         my $total = 0;
         my %found;
         foreach my $item (keys(%{$rhn_items})) {
@@ -492,7 +796,7 @@ sub update_rhn_source {
         }
         close($fh);
         if ($total < 2) {
-            if (open($fh,">>$file")) {
+            if (open($fh,'>>',$file)) {
                 foreach my $item (keys(%{$rhn_items})) {
                     unless ($found{$item}) {
                         if (ref($rhn_items->{$item}) eq 'HASH') {
@@ -519,12 +823,15 @@ sub update_rhn_source {
 
 =item &update_apt_source()
 
-Modifies the source.list file which includes repositories used by apt-get
+Modifies either the sources.list or sources.list.d/loncapa.list 
+file which include repositories used by apt-get.
 
 Inputs:
-$deb_row - a reference to containing the regular expression
-to test for, and the text string to append to the file, if an entry for the
-LON-CAPA Debian/ or Ubuntu repository is missing.
+$distname - distro (without version): debian or ubuntu
+$distver - distro version, e.g., 12 or 24
+$deb_row - a reference to a hash containing the regular expression
+to test for, and the text string to append to the file, if an entry 
+for the LON-CAPA Debian/ or Ubuntu repository is missing.
 
 Returns: 0 or 1, indicating if the file was modified(1) or not(0).
 
@@ -535,19 +842,27 @@ Returns: 0 or 1, indicating if the file
 #################################################################
 #################################################################
 sub update_apt_source {
-    my ($deb_row) = @_;
+    my ($distname,$distver,$deb_row) = @_;
     return 0 if (ref($deb_row) ne 'HASH');
     return 0 if (($deb_row->{regexp} eq '') || ($deb_row->{text} eq ''));
     my $file = '/etc/apt/sources.list';
+    my $nobackup;
+    if ((($distname eq 'ubuntu') && ($distver > 20)) ||
+        (($distname eq 'debian') && ($distver >= 10))) {
+        $file = '/etc/apt/sources.list.d/loncapa.list';
+        $nobackup = 1;
+    }
     return 0 if (! -e $file);
-    my $backup = $file.'.backup';
-    if (! copy($file,$backup)) {
-        warn "**** Error: Unable to make backup of $file";
-        return 0;
+    unless ($nobackup) {
+        my $backup = $file.'.backup';
+        if (! copy($file,$backup)) {
+            warn "**** Error: Unable to make backup of $file";
+            return 0;
+        }
     }
     my $result = 0;
     my $fh;
-    if (open($fh,"<$file")) {
+    if (open($fh,'<',$file)) {
         my $found = 0;
         my $pattern = $deb_row->{regexp};
         while(<$fh>) {
@@ -558,7 +873,7 @@ sub update_apt_source {
         }
         close($fh);
         if (!$found) {
-            if (open($fh,">>$file")) {
+            if (open($fh,'>>',$file)) {
                 print $fh "\n".$deb_row->{text}."\n";
                 close($fh);
                 $result = 1;