3 files changed, 260 insertions, 8 deletions

diff --git a/build.conf b/build.conf
index a9c6d49..5c4dbb6 100644
--- a/build.conf
+++ b/build.conf
@@ -4,6 +4,7 @@ default action: check "libbu++.a"
 "clean" action: clean targets()
 "tests" action: check targets() filter regexp("^tests/.*$")
 "all" action: check targets()
+"fstring" action: check "tests/fstring"
 
 set "CXXFLAGS" += "-ggdb -Wall"
 
diff --git a/src/fstring.h b/src/fstring.h
index 2eaa4ba..287641f 100644
--- a/src/fstring.h
+++ b/src/fstring.h
@@ -4,28 +4,251 @@
 #include <stdint.h>
 #include <memory>
 
+template< typename chr=char >
+struct FStringChunk
+{
+        long nLength;
+        chr *pData;
+        FStringChunk *pNext;
+};
+
 /**
  *
  */
-template< typename chr, typename chralloc = std::allocator<chr> >
-class FString
+template< typename chr=char, typename chralloc=std::allocator<chr>, typename chunkalloc=std::allocator<struct FStringChunk<chr> > >
+class FBasicString
 {
+private:
+        typedef struct FStringChunk<chr> Chunk;
+
 public:
-        FString() :
-                pData( NULL ),
-                pnRefs( NULL )
+        FBasicString() :
+                nLength( 0 ),
+                pnRefs( NULL ),
+                pFirst( NULL ),
+                pLast( NULL )
+        {
+        }
+
+        FBasicString( const chr *pData ) :
+                nLength( 0 ),
+                pnRefs( NULL ),
+                pFirst( NULL ),
+                pLast( NULL )
+        {
+                append( pData );
+        }
+
+        FBasicString( const chr *pData, long nLength ) :
+                nLength( 0 ),
+                pnRefs( NULL ),
+                pFirst( NULL ),
+                pLast( NULL )
+        {
+                append( pData, nLength );
+        }
+
+        virtual ~FBasicString()
+        {
+        }
+
+        void append( const chr *pData )
+        {
+                long nLen;
+                for( nLen = 0; pData[nLen] != (chr)0; nLen++ );
+                
+                Chunk *pNew = newChunk( nLen );
+                memcpy( pNew->pData, pData, nLen * sizeof(chr) );
+
+                appendChunk( pNew );
+        }
+
+        void append( const chr *pData, long nLen )
+        {
+                Chunk *pNew = newChunk( nLen );
+                
+                memcpy( pNew->pData, pData, nLen * sizeof(chr) );
+
+                appendChunk( pNew );
+        }
+
+        void prepend( const chr *pData )
+        {
+                long nLen;
+                for( nLen = 0; pData[nLen] != (chr)0; nLen++ );
+                
+                Chunk *pNew = newChunk( nLen );
+                memcpy( pNew->pData, pData, nLen * sizeof(chr) );
+
+                prependChunk( pNew );
+        }
+
+        void prepend( const chr *pData, long nLen )
+        {
+                Chunk *pNew = newChunk( nLen );
+                
+                memcpy( pNew->pData, pData, nLen * sizeof(chr) );
+
+                prependChunk( pNew );
+        }
+
+        void clear()
+        {
+                if( pFirst == NULL )
+                        return;
+
+                Chunk *i = pFirst;
+                for(;;)
+                {
+                        Chunk *n = i->pNext;
+                        aChr.deallocate( i->pData, i->nLength+1 );
+                        aChunk.deallocate( i, 1 );
+                        if( n == NULL )
+                                break;
+                        i = n;
+                }
+                pFirst = pLast = NULL;
+                nLength = 0;
+        }
+
+        chr *c_str()
+        {
+                if( pFirst == NULL )
+                        return NULL;
+
+                flatten();
+                return pFirst->pData;
+        }
+
+        FBasicString<chr, chralloc, chunkalloc> &operator +=( const chr *pData )
         {
+                append( pData );
+
+                return (*this);
         }
 
-        virtual ~FString()
+        FBasicString<chr, chralloc, chunkalloc> &operator =( const chr *pData )
         {
+                clear();
+                append( pData );
+
+                return (*this);
+        }
+
+        bool operator ==( const chr *pData )
+        {
+                if( pFirst == NULL ) {
+                        if( pData == NULL )
+                                return true;
+                        return false;
+                }
+
+                flatten();
+                const chr *a = pData;
+                chr *b = pFirst->pData;
+                for( ; *a!=(chr)0; a++, b++ )
+                {
+                        if( *a != *b )
+                                return false;
+                }
+
+                return true;
+        }
+
+        bool operator !=(const chr *pData )
+        {
+                return !(*this == pData);
+        }
+
+
+
+private:
+        void flatten()
+        {
+                if( isFlat() )
+                        return;
+
+                if( pFirst == NULL )
+                        return;
+
+                Chunk *pNew = newChunk( nLength );
+                chr *pos = pNew->pData;
+                Chunk *i = pFirst;
+                for(;;)
+                {
+                        memcpy( pos, i->pData, i->nLength*sizeof(chr) );
+                        pos += i->nLength;
+                        i = i->pNext;
+                        if( i == NULL )
+                                break;
+                }
+                clear();
+
+                appendChunk( pNew );
+        }
+        
+        bool isFlat()
+        {
+                return (pFirst == pLast);
+        }
+
+        bool isShared()
+        {
+                return (pnRefs != NULL);
+        }
+
+        Chunk *newChunk()
+        {
+                Chunk *pNew = aChunk.allocate( 1 );
+                pNew->pNext = NULL;
+                return pNew;
+        }
+        
+        Chunk *newChunk( long nLen )
+        {
+                Chunk *pNew = aChunk.allocate( 1 );
+                pNew->pNext = NULL;
+                pNew->nLength = nLen;
+                pNew->pData = aChr.allocate( nLen+1 );
+                return pNew;
+        }
+
+        void appendChunk( Chunk *pNewChunk )
+        {
+                if( pFirst == NULL )
+                        pLast = pFirst = pNewChunk;
+                else
+                {
+                        pLast->pNext = pNewChunk;
+                        pLast = pNewChunk;
+                }
+
+                nLength += pNewChunk->nLength;
+        }
+        
+        void prependChunk( Chunk *pNewChunk )
+        {
+                if( pFirst == NULL )
+                        pLast = pFirst = pNewChunk;
+                else
+                {
+                        pNewChunk->pNext = pFirst;
+                        pFirst = pNewChunk;
+                }
+
+                nLength += pNewChunk->nLength;
         }
 
 private:
         long nLength;
-        chr *pData;
         uint32_t *pnRefs;
-        chralloc aChars;
+        Chunk *pFirst;
+        Chunk *pLast;
+
+        chralloc aChr;
+        chunkalloc aChunk;
 };
 
+typedef FBasicString<char> FString;
+
 #endif
diff --git a/src/tests/fstring.cpp b/src/tests/fstring.cpp
new file mode 100644
index 0000000..26905ac
--- /dev/null
+++ b/src/tests/fstring.cpp
@@ -0,0 +1,28 @@
+#include "fstring.h"
+
+int main( int argc, char *argv )
+{
+        FString str("[] this won't be in there", 3);
+
+        str.append("Hello");
+        str.append(" th");
+        str.append("ere.");
+
+        if( str == "[] Hello there." )
+                printf("1) check\n");
+
+        if( str != "[] Hello there. " )
+                printf("2) check\n");
+
+        if( str != "[] Hello there." )
+                printf("3) failed\n");
+        else
+                printf("3) check\n");
+
+        str += "  How are you?";
+
+        str.prepend("Bob says:  ");
+
+        printf("%s\n", str.c_str() );
+}
+