1 files changed, 112 insertions, 0 deletions
diff --git a/docs/samples/save_custom_writer.cpp b/docs/samples/save_custom_writer.cpp
new file mode 100644
index 0000000..978c583
--- /dev/null
+++ b/docs/samples/save_custom_writer.cpp
@@ -0,0 +1,112 @@
+#include "pugixml.hpp"
+
+#include <string>
+
+#include <stdio.h>
+
+struct xml_string_writer: pugi::xml_writer
+{
+	std::string result;
+
+	virtual void write(const void* data, size_t size)
+	{
+		result += std::string(static_cast<const char*>(data), size);
+	}
+};
+
+struct xml_memory_writer: pugi::xml_writer
+{
+	char* buffer;
+	size_t capacity;
+
+	size_t result;
+
+	xml_memory_writer(): buffer(0), capacity(0), result(0)
+	{
+	}
+
+	xml_memory_writer(char* buffer, size_t capacity): buffer(buffer), capacity(capacity), result(0)
+	{
+	}
+
+	size_t written_size() const
+	{
+		return result < capacity ? result : capacity;
+	}
+
+	virtual void write(const void* data, size_t size)
+	{
+		if (result < capacity)
+		{
+			size_t chunk = (capacity - result < size) ? capacity - result : size;
+
+			memcpy(buffer + result, data, chunk);
+		}
+
+		result += size;
+	}
+};
+
+std::string node_to_string(pugi::xml_node node)
+{
+	xml_string_writer writer;
+	node.print(writer);
+
+	return writer.result;
+}
+
+char* node_to_buffer(pugi::xml_node node, char* buffer, size_t size)
+{
+	if (size == 0) return buffer;
+
+	// leave one character for null terminator
+	xml_memory_writer writer(buffer, size - 1);
+	node.print(writer);
+
+	// null terminate
+	buffer[writer.written_size()] = 0;
+
+	return buffer;
+}
+
+char* node_to_buffer_heap(pugi::xml_node node)
+{
+	// first pass: get required memory size
+	xml_memory_writer counter;
+	node.print(counter);
+
+	// allocate necessary size (+1 for null termination)
+	char* buffer = new char[counter.result + 1];
+
+	// second pass: actual printing
+	xml_memory_writer writer(buffer, counter.result);
+	node.print(writer);
+
+	// null terminate
+	buffer[writer.written_size()] = 0;
+
+	return buffer;
+}
+
+int main()
+{
+	// get a test document
+	pugi::xml_document doc;
+	doc.load("<foo bar='baz'>hey</foo>");
+
+	// get contents as std::string (single pass)
+	printf("contents: [%s]\n", node_to_string(doc).c_str());
+
+	// get contents into fixed-size buffer (single pass)
+	char large_buf[128];
+	printf("contents: [%s]\n", node_to_buffer(doc, large_buf, sizeof(large_buf)));
+
+	// get contents into fixed-size buffer (single pass, shows truncating behavior)
+	char small_buf[22];
+	printf("contents: [%s]\n", node_to_buffer(doc, small_buf, sizeof(small_buf)));
+
+	// get contents into heap-allocated buffer (two passes)
+	char* heap_buf = node_to_buffer_heap(doc);
+	printf("contents: [%s]\n", heap_buf);
+	delete[] heap_buf;
+}