[Bug] Exit if cmd_{pre,post}exec fail [sf#36]

[Benedikt Heine]

Reported by jasperla on 2012-06-15 07:56 UTC
Currently rsnapshot will just continue trying to do it's thing, even if cmd_{pre,post}exec fail for whatever reason. This can be quite nasty in case the
preexec script is meant to mount the target filesystem for example.

This patch adds support for cmd_preexec_error and cmd_postexec_error, a boolean variable.

[Benedikt Heine]

Commented by jasperla on 2012-06-15 07:56 UTC
Implement cmd_{pre,post}exec_error options.
Attached filersnapshot.diff:

--- rsnapshot.conf.default.in.orig  Sun Apr 27 12:26:16 2008
+++ rsnapshot.conf.default.in   Fri Jun 15 09:34:03 2012
@@ -80,6 +80,14 @@ snapshot_root    /.snapshots/
 #
 #cmd_postexec  /path/to/postexec/script

+# If cmd_preexec_error is enabled, rsnapshot will treat a non-zero return-code from
+# cmd_preexec as fatal and will exit.
+#cmd_preexec_error 1
+
+# If cmd_postexec_error is enabled, rsnapshot will treat a non-zero return-code from
+# cmd_postexec as fatal and will exit.
+#cmd_postexec_error    1
+
 #########################################
 #           BACKUP INTERVALS            #
 # Must be unique and in ascending order #
--- rsnapshot-program.pl.orig   Sun Aug 31 13:17:07 2008
+++ rsnapshot-program.pl    Fri Jun 15 09:32:20 2012
@@ -829,7 +829,43 @@ sub parse_config_file {
            $line_syntax_ok = 1;
            next;
        }
-       
+
+       # CHECK FOR cmd_preexec_error (optional)
+       if ($var eq 'cmd_preexec_error') {
+           if (defined($value)) {
+               if ('1' eq $value) {
+                   $config_vars{'cmd_preexec_error'} = 1;
+                   $line_syntax_ok = 1;
+                   next;
+               } elsif ('0' eq $value) {
+                   $config_vars{'cmd_preexec_error'} = 0;
+                   $line_syntax_ok = 1;
+                   next;
+               } else {
+                   config_err($file_line_num, "$line - cmd_preexec_error must be set to either 1 or 0");
+                   next;
+               }
+           }
+       }
+
+       # CHECK FOR cmd_postexec_error (optional)
+       if ($var eq 'cmd_postexec_error') {
+           if (defined($value)) {
+               if ('1' eq $value) {
+                   $config_vars{'cmd_postexec_error'} = 1;
+                   $line_syntax_ok = 1;
+                   next;
+               } elsif ('0' eq $value) {
+                   $config_vars{'cmd_postexec_error'} = 0;
+                   $line_syntax_ok = 1;
+                   next;
+               } else {
+                   config_err($file_line_num, "$line - cmd_preexec_error must be set to either 1 or 0");
+                   next;
+               }
+           }
+       }
+
        # CHECK FOR rsnapshot-diff (optional)
        if ($var eq 'cmd_rsnapshot_diff') {
                         $value =~ s/\s+$//;                         $value =~ s/\s+$//;
@@ -4058,13 +4092,25 @@ sub exec_cmd_preexec {
    }

    if (!defined($retval)) {
-       print_err("$config_vars{'cmd_preexec'} not found", 2);
+       if (1 == $config_vars{'cmd_preexec_error'}) {
+           print_err ("$config_vars{'cmd_preexec'} not found", 2);
+           syslog_err("$config_vars{'cmd_preexec'} not found");
+           exit(1);
+       } else {
+           print_err ("$config_vars{'cmd_preexec'} not found", 2);
+       }
    }
-   
+
    if (0 != $retval) {
-       print_warn("cmd_preexec \"$config_vars{'cmd_preexec'}\" returned $retval", 2);
+       if (1 == $config_vars{'cmd_preexec_error'}) {
+           print_err ("cmd_preexec \"$config_vars{'cmd_preexec'}\" returned $retval", 2);
+           syslog_err ("cmd_preexec \"$config_vars{'cmd_preexec'}\" returned $retval");
+           exit(1);
+       } else {
+           print_warn("cmd_preexec \"$config_vars{'cmd_preexec'}\" returned $retval", 2);
+       }
    }
-   
+
    return ($retval);
 }

@@ -4079,13 +4125,25 @@ sub exec_cmd_postexec {
    }

    if (!defined($retval)) {
-       print_err("$config_vars{'cmd_postexec'} not found", 2);
+       if (1 == $config_vars{'cmd_postexec_error'}) {
+           print_err ("$config_vars{'cmd_postexec'} not found", 2);
+           syslog_err("$config_vars{'cmd_postexec'} not found");
+           exit(1);
+       } else {
+           print_err ("$config_vars{'cmd_postexec'} not found", 2);
+       }
    }

    if (0 != $retval) {
-       print_warn("cmd_postexec \"$config_vars{'cmd_postexec'}\" returned $retval", 2);
+       if (1 == $config_vars{'cmd_postexec_error'}) {
+           print_err ("cmd_postexec \"$config_vars{'cmd_postexec'}\" returned $retval", 1);
+           syslog_err ("cmd_postexec \"$config_vars{'cmd_postexec'}\" returned $retval");
+           exit(1);
+       } else {
+           print_warn("cmd_postexec \"$config_vars{'cmd_postexec'}\" returned $retval", 2);
+       }
    }
-   
+
    return ($retval);
 }

@@ -6206,6 +6260,17 @@ rotations).

 =back

+B<cmd_preexec_error>
+
+B<cmd_postexec_error>
+
+=over 4
+
+If set to 1, rsnapshot will treat any non-zero return code from the
+cmd_preexec, cmd_postexec commands as fatal and will exit.
+
+=back
+
 B<linux_lvm_cmd_lvcreate>

 B<linux_lvm_cmd_lvremove>

[Benedikt Heine]

ported to main repository: rsnapshot/rsnapshot#74