8214720: Add pandoc filter to improve html man page output

Co-authored-by: Jonathan Gibbons <jonathan.gibbons@oracle.com>
Reviewed-by: erikj

make/scripts/pandoc-html-manpage-filter.js

@@ -0,0 +1,125 @@
+//
+// Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+// DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+//
+// This code is free software; you can redistribute it and/or modify it
+// under the terms of the GNU General Public License version 2 only, as
+// published by the Free Software Foundation.
+//
+// This code is distributed in the hope that it will be useful, but WITHOUT
+// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+// FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+// version 2 for more details (a copy is included in the LICENSE file that
+// accompanied this code).
+//
+// You should have received a copy of the GNU General Public License version
+// 2 along with this work; if not, write to the Free Software Foundation,
+// Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+//
+// Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+// or visit www.oracle.com if you need additional information or have any
+// questions.
+//
+
+//
+// Traverse a tree of pandoc format objects, calling callback on each
+// element, and replacing it if callback returns a new object.
+//
+// Inspired by the walk method in
+// https://github.com/jgm/pandocfilters/blob/master/pandocfilters.py
+//
+function traverse(obj, callback) {
+    if (Array.isArray(obj)) {
+        var processed_array = [];
+        obj.forEach(function(elem) {
+            if (elem === Object(elem) && elem.t) {
+                var replacement = callback(elem.t, elem.c || []);
+                if (!replacement) {
+                    // no replacement object returned, use original
+                    processed_array.push(traverse(elem, callback));
+                } else if (Array.isArray(replacement)) {
+                    // array of objects returned, splice all elements into array
+                    replacement.forEach(function(repl_elem) {
+                        processed_array.push(traverse(repl_elem, callback));
+                    })
+                } else {
+                    // replacement object given, traverse it
+                    processed_array.push(traverse(replacement, callback));
+                }
+            } else {
+                processed_array.push(traverse(elem, callback));
+            }
+        })
+        return processed_array;
+    } else if (obj === Object(obj)) {
+        if (obj.t) {
+            var replacement = callback(obj.t, obj.c || []);
+            if (replacement) {
+                return replacement;
+            }
+        }
+        var processed_obj = {};
+        Object.keys(obj).forEach(function(key) {
+            processed_obj[key] = traverse(obj[key], callback);
+        })
+        return processed_obj;
+    } else {
+        return obj;
+    }
+}
+
+//
+// Helper constructors to create pandoc format objects
+//
+function Space() {
+    return { 't': 'Space' };
+}
+
+function Str(value) {
+    return { 't': 'Str', 'c': value };
+}
+
+function MetaInlines(value) {
+    return { 't': 'MetaInlines', 'c': value };
+}
+
+function change_title(type, value) {
+    if (type === 'MetaInlines') {
+        if (value[0].t === 'Str') {
+            var match = value[0].c.match(/^([A-Z]+)\([0-9]+\)$/);
+            if (match) {
+                return MetaInlines([
+                        Str("The"), Space(),
+			Str(match[1].toLowerCase()),
+			Space(), Str("Command")
+		    ]);
+            }
+        }
+    }
+}
+
+//
+// Main function
+//
+function main() {
+    var input = "";
+    while (line = readLine()) {
+        input = input.concat(line);
+    }
+
+    var json = JSON.parse(input);
+
+    var meta = json.meta;
+    if (meta) {
+        meta.date = undefined;
+        var title = meta.title;
+        if (meta.title) {
+            meta.title = traverse(meta.title, change_title);
+        }
+    }
+
+    print(JSON.stringify(json));
+}
+
+// ... and execute it
+main();

make/scripts/pandoc-html-manpage-filter.sh.template

@@ -25,4 +25,4 @@
 # Simple wrapper script to call Nashorn with the javascript pandoc filter
 
 @@BOOT_JDK@@/bin/jjs @@JJS_FLAGS@@ -scripting \
-    "@@TOPDIR@@/make/scripts/pandoc-manpage-filter.js" 2> /dev/null
+    "@@TOPDIR@@/make/scripts/pandoc-html-manpage-filter.js" 2> /dev/null

make/scripts/pandoc-troff-manpage-filter.sh.template

@@ -0,0 +1,28 @@
+#!/bin/bash
+#
+# Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
+# DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+#
+# This code is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License version 2 only, as
+# published by the Free Software Foundation.
+#
+# This code is distributed in the hope that it will be useful, but WITHOUT
+# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+# FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+# version 2 for more details (a copy is included in the LICENSE file that
+# accompanied this code).
+#
+# You should have received a copy of the GNU General Public License version
+# 2 along with this work; if not, write to the Free Software Foundation,
+# Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+#
+# Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+# or visit www.oracle.com if you need additional information or have any
+# questions.
+#
+
+# Simple wrapper script to call Nashorn with the javascript pandoc filter
+
+@@BOOT_JDK@@/bin/jjs @@JJS_FLAGS@@ -scripting \
+    "@@TOPDIR@@/make/scripts/pandoc-troff-manpage-filter.js" 2> /dev/null