Fix sign bug

Prevent blockSize from exceeding file's length

Author: Antidote

include/Athena/FileReader.hpp

@@ -12,7 +12,7 @@ namespace io
 class FileReader : public IStreamReader
 {
 public:
-    FileReader(const std::string& filename, atUint32 cacheSize = (32 * 1024));
+    FileReader(const std::string& filename, atInt32 cacheSize = (32 * 1024));
     virtual ~FileReader();
     inline const std::string& filename() const
     {return m_filename;}
@@ -27,12 +27,12 @@ class FileReader : public IStreamReader
     atUint64 length() const;
     atUint64 readUBytesToBuf(void* buf, atUint64 len);
 
-    void setCacheSize(const atUint32 blockSize);
+    void setCacheSize(const atInt32 blockSize);
 protected:
     std::string  m_filename;
     FILE*        m_fileHandle;
     std::unique_ptr<atUint8[]>    m_cacheData;
-    atUint32     m_blockSize;
+    atInt32     m_blockSize;
     atInt32      m_curBlock;
     atUint64     m_offset;
 };

src/Athena/FileReader.cpp

@@ -14,7 +14,7 @@ namespace Athena
 {
 namespace io
 {
-FileReader::FileReader(const std::string& filename, atUint32 cacheSize)
+FileReader::FileReader(const std::string& filename, atInt32 cacheSize)
     : m_filename(filename),
       m_fileHandle(nullptr),
       m_cacheData(nullptr),
@@ -145,9 +145,13 @@ atUint64 FileReader::readUBytesToBuf(void* buf, atUint64 len)
     }
 }
 
-void FileReader::setCacheSize(const atUint32 blockSize)
+void FileReader::setCacheSize(const atInt32 blockSize)
 {
     m_blockSize = blockSize;
+
+    if (m_blockSize > length())
+        m_blockSize = length();
+
     m_curBlock = -1;
     if (m_blockSize > 0)
         m_cacheData.reset(new atUint8[m_blockSize]);