From e590d90bf60ad0d798289143bc5e21c9abe1d39c Mon Sep 17 00:00:00 2001
From: Norman Feske <norman.feske@genode-labs.com>
Date: Tue, 22 Sep 2015 17:09:22 +0200
Subject: [PATCH] xml_generator: support appending of node content

The new 'Xml_generator::append' method can be used to append strings
into the body of an XML node.
---
 repos/os/include/util/xml_generator.h | 56 +++++++++++++++++++++++----
 1 file changed, 49 insertions(+), 7 deletions(-)

diff --git a/repos/os/include/util/xml_generator.h b/repos/os/include/util/xml_generator.h
index 89a879f6e..a35313c23 100644
--- a/repos/os/include/util/xml_generator.h
+++ b/repos/os/include/util/xml_generator.h
@@ -15,6 +15,7 @@
 #define _INCLUDE__UTIL__XML_GENERATOR_H_
 
 #include <util/string.h>
+#include <util/print_lines.h>
 #include <base/snprintf.h>
 
 namespace Genode { class Xml_generator; }
@@ -110,10 +111,20 @@ class Genode::Xml_generator
 					return Out_buffer(_dst + at, len);
 				}
 
+				bool has_trailing_newline() const
+				{
+					return (_used > 1) && (_dst[_used - 1] == '\n');
+				}
+
 				/**
 				 * Return number of unused bytes of the buffer
 				 */
 				size_t used() const { return _used; }
+
+				void discard_trailing_whitespace()
+				{
+					for (; _used > 0 && is_whitespace(_dst[_used - 1]); _used--);
+				}
 		};
 
 
@@ -130,7 +141,8 @@ class Genode::Xml_generator
 
 				Out_buffer _out_buffer;
 
-				bool _has_sub_nodes  = false;
+				bool _has_content    = false;
+				bool _is_indented    = false;
 				bool _has_attributes = false;
 
 				/**
@@ -140,15 +152,23 @@ class Genode::Xml_generator
 
 				/**
 				 * Called by sub node
+				 *
+				 * \param indented  if true, the returned buffer and the
+				 *                  end tag start at a fresh line. This is the
+				 *                  case if the content buffer contains sub
+				 *                  nodes. But when inserting raw content,
+				 *                  such additional whitespaces are not desired.
 				 */
-				Out_buffer _content_buffer()
+				Out_buffer _content_buffer(bool indented)
 				{
-					if (!_has_sub_nodes)
+					if (!_has_content)
 						_out_buffer.append(">");
 
-					_out_buffer.append("\n");
+					if (indented)
+						_out_buffer.append("\n");
 
-					_has_sub_nodes = true;
+					_has_content = true;
+					_is_indented = indented;
 
 					return _out_buffer.remainder();
 				}
@@ -178,12 +198,21 @@ class Genode::Xml_generator
 					_attr_offset += gap;
 				}
 
+				void append(char const *src, size_t src_len)
+				{
+					Out_buffer content_buffer = _content_buffer(false);
+
+					content_buffer.append(src, src_len);
+
+					_commit_content(content_buffer);
+				}
+
 				template <typename FUNC>
 				Node(Xml_generator &xml, char const *name, FUNC const &func)
 				:
 					_indent_level(xml._curr_indent),
 					_parent_node(xml._curr_node),
-					_out_buffer(_parent_node ? _parent_node->_content_buffer()
+					_out_buffer(_parent_node ? _parent_node->_content_buffer(true)
 					                         : xml._out_buffer)
 				{
 					_out_buffer.append('\t', _indent_level);
@@ -202,9 +231,12 @@ class Genode::Xml_generator
 					xml._curr_node = _parent_node;
 					xml._curr_indent--;
 
-					if (_has_sub_nodes) {
+					if (_is_indented) {
 						_out_buffer.append("\n");
 						_out_buffer.append('\t', _indent_level);
+					}
+
+					if (_has_content) {
 						_out_buffer.append("</");
 						_out_buffer.append(name);
 						_out_buffer.append(">");
@@ -258,6 +290,16 @@ class Genode::Xml_generator
 			_curr_node->insert_attribute(name, buf);
 		}
 
+		/**
+		 * Append content to XML node
+		 *
+		 * This method must not be followed by calls of 'attribute'.
+		 */
+		void append(char const *str, size_t str_len = ~0UL)
+		{
+			_curr_node->append(str, str_len == ~0UL ? strlen(str) : str_len);
+		}
+
 		size_t used() const { return _out_buffer.used(); }
 };