include/fc/io/raw.hpp

@@ -192,6 +192,16 @@ namespace fc {
        v = std::make_shared<const T>(std::move(tmp));
     } FC_RETHROW_EXCEPTIONS( warn, "std::shared_ptr<const T>", ("type",fc::get_typename<T>::name()) ) }
 
+    template<typename Stream> inline void pack( Stream& s, const signed_int& v, uint32_t _max_depth ) {
+      uint32_t val = (v.value<<1) ^ (v.value>>31);
+      do {
+        uint8_t b = uint8_t(val) & 0x7f;
+        val >>= 7;
+        b |= ((val > 0) << 7);
+        s.write((char*)&b,1);//.put(b);
+      } while( val );
+    }
+
     template<typename Stream> inline void pack( Stream& s, const unsigned_int& v, uint32_t _max_depth ) {
       uint64_t val = v.value;
       do {
@@ -202,6 +212,17 @@ namespace fc {
       }while( val );
     }
 
+    template<typename Stream> inline void unpack( Stream& s, signed_int& vi, uint32_t _max_depth ) {
+      uint32_t v = 0; char b = 0; int by = 0;
+      do {
+        s.get(b);
+        v |= uint32_t(uint8_t(b) & 0x7f) << by;
+        by += 7;
+      } while( (uint8_t(b) & 0x80) && by < 32 );
+      vi.value = ((v>>1) ^ (v>>31)) + (v&0x01);
+      vi.value = v&0x01 ? vi.value : -vi.value;
+      vi.value = -vi.value;
+    }
     template<typename Stream> inline void unpack( Stream& s, unsigned_int& vi, uint32_t _max_depth ) {
       uint64_t v = 0; char b = 0; uint8_t by = 0;
       do {

include/fc/io/raw_fwd.hpp

@@ -119,6 +119,9 @@ namespace fc {
     template<typename Stream, typename T> inline void pack( Stream& s, const std::vector<T>& v, uint32_t _max_depth=FC_PACK_MAX_DEPTH );
     template<typename Stream, typename T> inline void unpack( Stream& s, std::vector<T>& v, uint32_t _max_depth=FC_PACK_MAX_DEPTH );
 
+    template<typename Stream> inline void pack( Stream& s, const signed_int& v, uint32_t _max_depth=FC_PACK_MAX_DEPTH );
+    template<typename Stream> inline void unpack( Stream& s, signed_int& vi, uint32_t _max_depth=FC_PACK_MAX_DEPTH );
+
     template<typename Stream> inline void pack( Stream& s, const unsigned_int& v, uint32_t _max_depth=FC_PACK_MAX_DEPTH );
     template<typename Stream> inline void unpack( Stream& s, unsigned_int& vi, uint32_t _max_depth=FC_PACK_MAX_DEPTH );
 

include/fc/io/varint.hpp

@@ -41,8 +41,42 @@ struct unsigned_int {
     friend bool operator>=( const unsigned_int& i, const unsigned_int& v ) { return i.value >= v.value; }
 };
 
+/**
+ *  @brief serializes a 32 bit signed interger in as few bytes as possible
+ *
+ *  Uses the google protobuf algorithm for seralizing signed numbers
+ */
+struct signed_int {
+    signed_int( int32_t v = 0 ):value(v){}
+    operator int32_t()const { return value; }
+    template<typename T>
+    signed_int& operator=( const T& v ) { value = v; return *this; }
+    signed_int operator++(int) { return value++; }
+    signed_int& operator++(){ ++value; return *this; }
+
+    int32_t value;
+
+    friend bool operator==( const signed_int& i, const int32_t& v )    { return i.value == v; }
+    friend bool operator==( const int32_t& i, const signed_int& v )    { return i       == v.value; }
+    friend bool operator==( const signed_int& i, const signed_int& v ) { return i.value == v.value; }
+
+    friend bool operator!=( const signed_int& i, const int32_t& v )    { return i.value != v; }
+    friend bool operator!=( const int32_t& i, const signed_int& v )    { return i       != v.value; }
+    friend bool operator!=( const signed_int& i, const signed_int& v ) { return i.value != v.value; }
+
+    friend bool operator<( const signed_int& i, const int32_t& v )     { return i.value < v; }
+    friend bool operator<( const int32_t& i, const signed_int& v )     { return i       < v.value; }
+    friend bool operator<( const signed_int& i, const signed_int& v )  { return i.value < v.value; }
+
+    friend bool operator>=( const signed_int& i, const int32_t& v )    { return i.value >= v; }
+    friend bool operator>=( const int32_t& i, const signed_int& v )    { return i       >= v.value; }
+    friend bool operator>=( const signed_int& i, const signed_int& v ) { return i.value >= v.value; }
+};
+
 class variant;
 
+void to_variant( const signed_int& var, variant& vo, uint32_t max_depth = 1 );
+void from_variant( const variant& var, signed_int& vo, uint32_t max_depth = 1 );
 void to_variant( const unsigned_int& var, variant& vo, uint32_t max_depth = 1 );
 void from_variant( const variant& var, unsigned_int& vo, uint32_t max_depth = 1 );
 
@@ -51,6 +85,15 @@ void from_variant( const variant& var, unsigned_int& vo, uint32_t max_depth = 1
 #include <unordered_map>
 namespace std
 {
+   template<>
+   struct hash<fc::signed_int>
+   {
+       public:
+         size_t operator()(const fc::signed_int &a) const 
+         {
+            return std::hash<int32_t>()(a.value);
+         }
+   };
    template<>
    struct hash<fc::unsigned_int>
    {

include/fc/reflect/typename.hpp

@@ -132,8 +132,10 @@ namespace fc {
       }
   };
 
+  struct signed_int;
   struct unsigned_int;
   class variant_object;
+  template<> struct get_typename<signed_int>   { static const char* name()   { return "signed_int";   } };
   template<> struct get_typename<unsigned_int>   { static const char* name()   { return "unsigned_int";   } };
   template<> struct get_typename<variant_object>   { static const char* name()   { return "fc::variant_object";   } };
 

src/io/varint.cpp

@@ -3,6 +3,8 @@
 
 namespace fc
 {
+void to_variant( const signed_int& var, variant& vo, uint32_t max_depth ) { vo = var.value; }
+void from_variant( const variant& var, signed_int& vo, uint32_t max_depth ) { vo.value = static_cast<int32_t>(var.as_int64()); }
 void to_variant( const unsigned_int& var, variant& vo, uint32_t max_depth )  { vo = var.value; }
 void from_variant( const variant& var, unsigned_int& vo, uint32_t max_depth )  { vo.value = var.as_uint64(); }
 }