[Minor] rspamd_stats: add time selectors

The parser should exit from the `while` loop when `--end`is reached instead of skipping lines, but I have no idea how to close the file handle properly in that case.

utils/rspamd_stats.pl

@@ -14,6 +14,8 @@ my $diff_alpha = 0.1;
 my $correlations = 0;
 my $log_file = "";
 my $search_pattern = "";
+my $startTime="";
+my $endTime;
 my $num_logs;
 my $exclude_logs = 0;
 my $man = 0;
@@ -34,6 +36,8 @@ GetOptions(
   "alpha|a=f" => \$diff_alpha,
   "correlations|c" => \$correlations,
   "search-pattern=s" => \$search_pattern,
+  "start=s" => \$startTime,
+  "end=s" => \$endTime,
   "num-logs|n=i" => \$num_logs,
   "exclude-logs|x=i" => \$exclude_logs,
   "help|?" => \$help,
@@ -194,13 +198,17 @@ sub ProcessLog {
     next if !$enabled;
 
     if (/^.*rspamd_task_write_log.*$/) {
-      $timeStamp{'end'} = join ' ', ( split /\s+/ )[ 0 .. 1 ];
+      my $ts = join ' ', ( split /\s+/ )[ 0 .. 1 ];
+
+      next if ( $ts lt $startTime );
+      next if ( defined $endTime && $ts gt $endTime );
 
       if ($_ !~ /\(([^()]+)\): \[(NaN|-?\d+(?:\.\d+)?)\/(-?\d+(?:\.\d+)?)\]\s+\[([^\]]+)\].+? time: (\d+\.\d+)ms real/) {
         #print "BAD: $_\n";
         next;
       }
 
+      $timeStamp{'end'} = $ts;
       $timeStamp{'start'} //= $timeStamp{'end'};
       $scanTime{'min'} = $5
         if ( !exists $scanTime{'min'} || $scanTime{'min'} > $5 );
@@ -375,6 +383,8 @@ rspamd_stats [options] [--symbol=SYM1 [--symbol=SYM2...]] [--log file]
    --alpha=value          set ignore score for symbols (0.1 by default)
    --correlations         enable correlations report
    --search-pattern       do not process input unless the desired pattern is found
+   --start                starting time (oldest) for log parsing
+   --end                  ending time (newest) for log parsing
    --num-logs=integer     number of recent logfiles to analyze (all files in the directory by default)
    --exclude-logs=integer number of latest logs to exclude (0 by default)
    --help                 brief help message
@@ -424,7 +434,19 @@ Additionaly print correlation rate for each symbol displayed. This routine calcu
 
 =item B<--search-pattern>
 
-Do not process input unless finding the specified regular expression. Useful to skip logs to certain date, for example, --search-pattern="2016-08-09 10:00:0[0-9]"
+Do not process input unless finding the specified regular expression. Useful to skip logs to a certain position.
+
+=item B<--start>
+
+Select log entries after this time. Format: C<YYYY-MM-DD HH:MM:SS> (can be
+truncated to any desired accuracy). If used with B<--end> select entries between
+B<--start> and B<--end>.
+
+=item B<--end>
+
+Select log entries before this time. Format: C<YYYY-MM-DD HH:MM:SS> (can be
+truncated to any desired accuracy). If used with B<--start> select entries between
+B<--start> and B<--end>.
 
 =item B<--help>