GLib based (un)quoting in C++

agent-ini/src/Makefile.am

@@ -13,7 +13,9 @@ liby2ag_ini_la_SOURCES =	\
 	IniParser.cc		\
 	IniParser.h		\
 	IniFile.cc		\
-	IniFile.h		
+	IniFile.h		\
+	quotes.cc		\
+	quotes.h
 
 liby2ag_ini_la_LDFLAGS = -version-info 2:0
 liby2ag_ini_la_LIBADD = @AGENT_LIBADD@

agent-ini/src/quotes.cc

@@ -0,0 +1,110 @@
+#include "quotes.h"
+
+using namespace std;
+
+string quote( string & unquoted_string)
+{
+    string dest = "'";
+
+    for( string::iterator sit = unquoted_string.begin(); sit < unquoted_string.end(); sit++)
+        if( *sit == '\'')
+            dest += "'\\''";
+        else
+            dest += *sit;
+
+    dest += "'";
+
+    return dest;
+}
+
+// helper
+// preconditions:
+// - starts with ['"]
+// - as a consequence: size > 0
+bool parse_quoted_string( string::iterator & sit, string::iterator last, string & ret)
+{
+    char quote_char = *( sit++);
+
+    if( quote_char == '"')
+    {
+        while( sit < last)
+        {
+            switch( *sit)
+            {
+                case '"':
+                    return true;
+
+                case '\\':
+                    switch( *(++sit))
+                    {
+                        case '"':
+                        case '\\':
+                        case '`':
+                        case '$':
+                        case '\n':
+                            ret += *(sit++);
+                            break;
+
+                        default:
+                            ret += '\\';
+                            break;
+                    }
+                    break;
+
+                default:
+                    ret += *(sit++);
+                    break;
+            }
+        }
+    }
+    else
+    {
+        while( sit < last)
+        {
+            if( *sit == '\'')
+            {
+                return true;
+            }
+            else
+            {
+                ret += *(sit++);
+            }
+        }
+    }
+
+    // missing closing quote
+    return false;
+}
+
+string unquote( string & quoted_string)
+{
+    string res;
+    string::iterator sit = quoted_string.begin();
+
+    while( sit < quoted_string.end())
+    {
+        while(  sit < quoted_string.end() && 
+                *sit != '"' && 
+                *sit != '\'')
+        {   
+            if( *sit == '\\')
+            {
+                if( *(++sit) != '\n')
+                    res += *sit;
+            }
+            else
+                res += *sit;
+
+            sit++;
+        }
+
+        if( !( sit < quoted_string.end()))
+            break;
+
+        string substr;
+        if( parse_quoted_string( sit, quoted_string.end(), substr))
+            res += substr;
+        sit++;
+    }
+    return res;
+}

agent-ini/src/quotes.h

@@ -0,0 +1,9 @@
+#ifndef __QUOTES_H__
+#define __QUOTES_H__
+
+#include <string>
+
+std::string quote( std::string & unquoted_string);
+std::string unquote( std::string & unquoted_string);
+
+#endif