+ implement string2bool converters

include/mapnik/util/conversions.hpp

@@ -32,6 +32,9 @@
 
 namespace mapnik { namespace util {
 
+MAPNIK_DECL bool string2bool(const char * value, bool & result);
+MAPNIK_DECL bool string2bool(std::string const& value, bool & result);
+
 MAPNIK_DECL bool string2int(const char * value, int & result);
 MAPNIK_DECL bool string2int(std::string const& value, int & result);
 

src/conversions.cpp

@@ -60,13 +60,53 @@ BOOST_SPIRIT_AUTO(qi, LONGLONG, qi::long_long)
 BOOST_SPIRIT_AUTO(qi, FLOAT, qi::float_)
 BOOST_SPIRIT_AUTO(qi, DOUBLE, qi::double_)
 
+
+
+struct bool_symbols : qi::symbols<char,bool>
+{
+    bool_symbols()
+    {
+        add("true",true)
+            ("false",false)
+            ("yes",true)
+            ("no",false)
+            ("on",true)
+            ("off",false)
+            ("1",true)
+            ("0",false);
+    }
+};
+
+bool string2bool(const char * value, bool & result)
+{
+    using boost::spirit::qi::no_case;
+    size_t length = strlen(value);
+    if (length < 1 || value == NULL)
+        return false;
+    const char *iter  = value;
+    const char *end   = value + length
+    bool r = qi::phrase_parse(iter,end, no_case[bool_symbols()] ,ascii::space,result);
+    return r && (iter == end);
+}
+
+bool string2bool(std::string const& value, bool & result)
+{
+    using boost::spirit::qi::no_case;
+    if (value.empty())
+        return false;
+    std::string::const_iterator str_beg = value.begin();
+    std::string::const_iterator str_end = value.end();
+    bool r = qi::phrase_parse(str_beg,str_end,no_case[bool_symbols()],ascii::space,result);
+    return r && (str_beg == str_end);
+}
+
 bool string2int(const char * value, int & result)
 {
     size_t length = strlen(value);
     if (length < 1 || value == NULL)
         return false;
-    const char *iter  = value;
+    const char *iter = value;
-    const char *end   = value + length;
+    const char *end  = value + length;
     bool r = qi::phrase_parse(iter,end,INTEGER,ascii::space,result);
     return r && (iter == end);
 }