gen: support 'redirect'

... and warn for too long --help lines

docs/cmdline-opts/MANPAGE.md

@@ -26,6 +26,7 @@ Each file has a set of meta-data and a body of text.
     Mutexed: (space separated list of options this overrides)
     Requires: (space separated list of features this option requires)
     See-also: (space separated list of related options)
+    Redirect: (option name to use instead)
     Help: (short text for the --help output for this option)
     --- (end of meta-data)
 

docs/cmdline-opts/gen.pl

@@ -10,6 +10,7 @@ my %optshort;
 my %optlong;
 my %helplong;
 my %arglong;
+my %redirlong;
 
 # get the long name version, return the man page string
 sub manpageify {
@@ -51,6 +52,7 @@ sub single {
     my $arg;
     my $mutexed;
     my $requires;
+    my $redirect;
     my $seealso;
     my $magic; # cmdline special option
     while(<F>) {
@@ -84,6 +86,9 @@ sub single {
         elsif(/^Requires: (.*)/i) {
             $requires=$1;
         }
+        elsif(/^Redirect: (.*)/i) {
+            $redirect=$1;
+        }
         elsif(/^---/) {
             last;
         }
@@ -109,6 +114,11 @@ sub single {
     }
 
     print ".IP \"$opt\"\n";
+    if($redirect) {
+        my $l = manpageify($redirect);
+        print "Use $l instead!\n";
+    }
+    else {
         my $o;
         if($protocols) {
             $o++;
@@ -122,8 +132,8 @@ sub single {
             $o++;
             print "[cmdline control] ";
         }
-
         print "\n" if($o);
+    }
 
     printdesc(@desc);
     undef @desc;
@@ -231,7 +241,12 @@ sub listhelp {
             $opt .= " $arg";
         }
 
-        printf " %-19s %s\n", $opt, $helplong{$f};
+        my $line = sprintf " %-19s %s\n", $opt, $helplong{$f};
+
+        if(length($line) > 79) {
+            print STDERR "WARN: the --$long line is too long\n";
+        }
+        print $line;
     }
 }