added ConstBufferReader

inc/hgl/io/ConstBufferReader.h

@@ -0,0 +1,149 @@
+#ifndef HGL_IO_CONST_BUFFER_READER_INCLUDE
+#define HGL_IO_CONST_BUFFER_READER_INCLUDE
+
+#include<hgl/type/String.h>
+#include<hgl/io/SeekOrigin.h>
+namespace hgl
+{
+    namespace io
+    {
+        class ConstBufferReader
+        {
+            const void *buffer;
+            const uint8 *pointer;
+            int64 size;
+
+        public:
+
+            ConstBufferReader(const void *buf,const int64 s)
+            {
+                buffer=buf;
+                pointer=(uint8 *)buffer;
+                size=s;
+            }
+
+            ConstBufferReader(ConstBufferReader &cbr,const int64 s)
+            {
+                buffer=cbr.CurPointer();
+                pointer=(uint8 *)buffer;
+                size=s;
+            }
+
+            template<typename T> bool Read(T &v)
+            {
+                if(size<sizeof(T))return(false);
+
+                v=*(T *)pointer;
+
+                pointer+=sizeof(T);
+
+                return(true);
+            }
+
+            template<typename T1,typename T2> bool CastRead(T2 &v)
+            {
+                if(size<sizeof(T1))return(false);
+
+                v=(T2)*(T1 *)pointer;
+
+                pointer+=sizeof(T1);
+
+                return(true);
+                
+            }
+
+            template<typename T> bool ReadArray(T *v,const int64 count)
+            {
+                if(size<count*sizeof(T))return(false);
+
+                memcpy(v,pointer,count*sizeof(T));
+
+                pointer+=count*sizeof(T);
+
+                return(true);
+            }
+
+        private:
+
+            template<typename T,typename S> int _ReadString(T *str)
+            {
+                if(!str)return(-1);
+
+                S str_len;
+
+                if(!Read<S>(str_len))return(-2);
+
+                if(!ReadArray<T>(str,(const int64)str_len))return(-3);
+
+                str[str_len]=0;
+
+                return str_len;
+            }
+
+            template<typename T,typename S> int _ReadString(String<T> &str)
+            {
+                S str_len;
+
+                if(!Read<S>(str_len))return(-2);
+
+                str.SetString((T *)pointer,str_len);
+
+                pointer+=str_len*sizeof(T);
+
+                return(str_len);
+            }
+
+        public:
+
+            template<typename T> int ReadTinyString (T *str){return _ReadString<T,uint8>(str);}
+            template<typename T> int ReadShortString(T *str){return _ReadString<T,uint16>(str);}
+            template<typename T> int ReadString     (T *str){return _ReadString<T,uint32>(str);}
+
+            template<typename T> int ReadTinyString (hgl::String<T> &str){return _ReadString<T,uint8>(str);}
+            template<typename T> int ReadShortString(hgl::String<T> &str){return _ReadString<T,uint16>(str);}
+            template<typename T> int ReadString     (hgl::String<T> &str){return _ReadString<T,uint32>(str);}
+
+            int64 GetSize()const{return size;}
+            int64 GetRemain()const{return size-(pointer-(uint8 *)buffer);}
+
+            int64 Tell()const{return pointer-(uint8 *)buffer;}
+            int64 Seek(const int64 offset,const SeekOrigin so=SeekOrigin::Begin)
+            {
+                int64 new_offset;
+
+                switch(so)
+                {
+                    case SeekOrigin::Begin:     new_offset=offset;break;
+                    case SeekOrigin::Current:   new_offset=pointer-(uint8 *)buffer+offset;break;
+                    case SeekOrigin::End:       new_offset=size+offset;break;
+                    default:return(-1);
+                }
+
+                if(new_offset>size)
+                    return(-1);
+
+                pointer=(uint8 *)buffer+new_offset;
+
+                return(new_offset);
+            }
+
+            int64 Skip(const int64 offset)
+            {
+                if(offset>size)
+                    return(-1);
+
+                pointer+=offset;
+
+                return(offset);
+            }
+
+            int64 Restart()
+            {
+                pointer=(uint8 *)buffer;
+            }
+
+            const void *CurPointer()const{return pointer;}
+        };//class ConstBufferReader
+    }//namespace io
+}//namespace hgl
+#endif//HGL_IO_CONST_BUFFER_READER_INCLUDE

inc/hgl/io/SeekAccess.h

@@ -1,18 +1,12 @@
 #ifndef HGL_IO_SEEK_ACCESS_INCLUDE
 #define HGL_IO_SEEK_ACCESS_INCLUDE
 
-#include<hgl/type/DataType.h>
+#include<hgl/platform/Platform.h>
+#include<hgl/io/SeekOrigin.h>
 namespace hgl
 {
     namespace io
     {
-        enum class SeekOrigin       /// 资源偏移方向枚举
-        {
-            Begin=0,              ///<从资源最开始处开始，offset必须大于0。移到资源的offset位置
-            Current,              ///<从资源当前位置开始，移到资源的Position+offset位置
-            End                   ///<从资源的结束位置开始，offset必须小于0，表示结束前的字符数
-        };//enum SeekOrigin
-
         /**
         * 定位访问功能基类
         */

inc/hgl/io/SeekOrigin.h

@@ -0,0 +1,16 @@
+#ifndef HGL_IO_SEEK_ORIGIN_INCLUDE
+#define HGL_IO_SEEK_ORIGIN_INCLUDE
+
+namespace hgl
+{
+    namespace io
+    {
+        enum class SeekOrigin     /// 资源偏移方向枚举
+        {
+            Begin=0,              ///<从资源最开始处开始，offset必须大于0。移到资源的offset位置
+            Current,              ///<从资源当前位置开始，移到资源的Position+offset位置
+            End                   ///<从资源的结束位置开始，offset必须小于0，表示结束前的字符数
+        };//enum SeekOrigin
+    }//namespace io
+}//namespace hgl
+#endif//HGL_IO_SEEK_ORIGIN_INCLUDE