added support for xml declarators, comments, quoted attribute values and parse error messages in xml parser

include/libtorrent/xml_parse.hpp

@@ -37,11 +37,14 @@ namespace libtorrent
 {
 	enum
 	{
-		xml_start_tag = 0,
-		xml_end_tag = 1,
-		xml_empty_tag = 2,
-		xml_string = 3,
-		xml_attribute = 4
+		xml_start_tag,
+		xml_end_tag,
+		xml_empty_tag,
+		xml_declaration_tag,
+		xml_string,
+		xml_attribute,
+		xml_comment,
+		xml_parse_error
 	};
 
 	// callback(int type, char const* str, char const* str2)
@@ -84,7 +87,13 @@ namespace libtorrent
 			for (; p != end && *p != '>'; ++p);
 
 			// parse error
-			if (p == end) break;
+			if (p == end)
+			{
+				token = xml_parse_error;
+				start = "unexpected end of file";
+				callback(token, start, val_start);
+				break;
+			}
 			
 			assert(*p == '>');
 			// save the character that terminated the tag name
@@ -107,6 +116,24 @@ namespace libtorrent
 				*(p-1) = '/';
 				tag_end = p - 1;
 			}
+			else if (*start == '?' && *(p-1) == '?')
+			{
+				*(p-1) = 0;
+				++start;
+				token = xml_declaration_tag;
+				callback(token, start, val_start);
+				*(p-1) = '?';
+				tag_end = p - 1;
+			}
+			else if (start + 5 < p && memcmp(start, "!--", 3) == 0 && memcmp(p-2, "--", 2) == 0)
+			{
+				start += 3;
+				*(p-2) = 0;
+				token = xml_comment;
+				callback(token, start, val_start);
+				*(p-2) = '-';
+				tag_end = p - 2;
+			}
 			else
 			{
 				token = xml_start_tag;
@@ -116,24 +143,59 @@ namespace libtorrent
 			*tag_name_end = save;
 
 			// parse attributes
-			start = tag_name_end;
 			for (char* i = tag_name_end; i < tag_end; ++i)
 			{
-				if (*i != '=') continue;
-				assert(*start == ' ');
-				++start;
+				// find start of attribute name
+				for (; i != tag_end && (*i == ' ' || *i == '\t'); ++i);
+				if (i == tag_end) break;
+				start = i;
+				// find end of attribute name
+				for (; i != tag_end && *i != '=' && *i != ' ' && *i != '\t'; ++i);
+				char* name_end = i;
+
+				// look for equality sign
+				for (; i != tag_end && *i != '='; ++i);
+
+				if (i == tag_end)
+				{
+					token = xml_parse_error;
+					val_start = 0;
+					start = "garbage inside element brackets";
+					callback(token, start, val_start);
+					break;
+				}
+
+				++i;
+				for (; i != tag_end && (*i == ' ' || *i == '\t'); ++i);
+				// check for parse error (values must be quoted)
+				if (i == tag_end || (*i != '\'' && *i != '\"'))
+				{
+					token = xml_parse_error;
+					val_start = 0;
+					start = "unquoted attribute value";
+					callback(token, start, val_start);
+					break;
+				}
+				char quote = *i;
+				++i;
 				val_start = i;
-				for (; i != tag_end && *i != ' '; ++i);
+				for (; i != tag_end && *i != quote; ++i);
+				// parse error (missing end quote)
+				if (i == tag_end)
+				{
+					token = xml_parse_error;
+					val_start = 0;
+					start = "missing end quote on attribute";
+					callback(token, start, val_start);
+					break;
+				}
 				save = *i;
 				*i = 0;
-				const_cast<char&>(*val_start) = 0;
-				++val_start;
+				*name_end = 0;
 				token = xml_attribute;
 				callback(token, start, val_start);
-				--val_start;
-				const_cast<char&>(*val_start) = '=';
+				*name_end = '=';
 				*i = save;
-				start = i;
 			}
 		}
 	

test/test_primitives.cpp

@@ -34,15 +34,24 @@ void parser_callback(std::string& out, int token, char const* s, char const* val
 		case xml_start_tag: out += "B"; break;
 		case xml_end_tag: out += "F"; break;
 		case xml_empty_tag: out += "E"; break;
+		case xml_declaration_tag: out += "D"; break;
+		case xml_comment: out += "C"; break;
 		case xml_string: out += "S"; break;
 		case xml_attribute: out += "A"; break;
+		case xml_parse_error: out += "P"; break;
+		default: TEST_CHECK(false);
 	}
 	out += s;
 	if (token == xml_attribute)
 	{
+		TEST_CHECK(val != 0);
 		out += "V";
 		out += val;
 	}
+	else
+	{
+		TEST_CHECK(val == 0);
+	}
 }
 
 int test_main()
@@ -127,13 +136,29 @@ int test_main()
 	std::cerr << out1 << std::endl;
 	TEST_CHECK(out1 == "BaSfooEbSbarFa");
 
-	char xml2[] = "<c x=1 y=3/><d foo=bar></d boo=foo>";
+	char xml2[] = "<?xml version = \"1.0\"?><c x=\"1\" \t y=\"3\"/><d foo='bar'></d boo='foo'><!--comment-->";
 	std::string out2;
 
 	xml_parse(xml2, xml2 + sizeof(xml2) - 1, bind(&parser_callback
 		, boost::ref(out2), _1, _2, _3));
 	std::cerr << out2 << std::endl;
-	TEST_CHECK(out2 == "EcAxV1AyV3BdAfooVbarFdAbooVfoo");
+	TEST_CHECK(out2 == "DxmlAversionV1.0EcAxV1AyV3BdAfooVbarFdAbooVfooCcomment");
+
+	char xml3[] = "<a f=1>foo</a f='b>";
+	std::string out3;
+
+	xml_parse(xml3, xml3 + sizeof(xml3) - 1, bind(&parser_callback
+		, boost::ref(out3), _1, _2, _3));
+	std::cerr << out3 << std::endl;
+	TEST_CHECK(out3 == "BaPunquoted attribute valueSfooFaPmissing end quote on attribute");
+
+	char xml4[] = "<a  f>foo</a  v  >";
+	std::string out4;
+
+	xml_parse(xml4, xml4 + sizeof(xml4) - 1, bind(&parser_callback
+		, boost::ref(out4), _1, _2, _3));
+	std::cerr << out4 << std::endl;
+	TEST_CHECK(out4 == "BaPgarbage inside element bracketsSfooFaPgarbage inside element brackets");
 	return 0;
 }