fhem.pl: escapeLogLine from Boris, forum#21232

git-svn-id: https://svn.fhem.de/fhem/trunk@5185 2b470e98-0d58-463d-a4d8-8e2adae1ed80

fhem/fhem.pl

@@ -90,6 +90,7 @@ sub fhz($);
 sub getAllGets($);
 sub getAllSets($);
 sub latin1ToUtf8($);
+sub escapeLogLine($);
 sub readingsBeginUpdate($);
 sub readingsBulkUpdate($$$@);
 sub readingsEndUpdate($$);
@@ -3148,6 +3149,13 @@ ReadingsVal($$$)
   return $default;
 }
 
+sub
+ReadingsNum($$$)
+{ 
+  my ($d,$n,$default) = @_;
+  return ReadingsVal($d,$n,$default)+0;
+}
+
 sub
 ReadingsTimestamp($$$)
 {
@@ -3691,6 +3699,23 @@ utf8ToLatin1($)
   return $s;
 }
 
+# replaces some common control chars by escape sequences
+# in order to make logs more readable
+sub escapeLogLine($) {
+  my ($s)= @_;
+  
+  my %escSequences = (
+      '\t' => "\\t",
+      '\n' => "\\n",
+      '\r' => "\\r",
+      );
+  
+  foreach my $regex (keys %escSequences) {
+    $s =~ s/$regex/$escSequences{$regex}/g;
+  }
+  return $s;
+}
+
 sub
 Debug($) {
   my $msg= shift;