runtime_loader: add simple vector implementation

std::vector requires libstdc++ which may be unsafe to use in runtime_loader.

src/system/runtime_loader/utility.h

@@ -1,4 +1,5 @@
 /*
+ * Copyright 2014, Paweł Dziepak, pdziepak@quarnos.org.
  * Copyright 2009, Ingo Weinhold, ingo_weinhold@gmx.de.
  * Distributed under the terms of the MIT License.
  */
@@ -7,6 +8,10 @@
 
 #include <OS.h>
 
+#include <string.h>
+
+#include <algorithm>
+
 
 #define	PAGE_MASK (B_PAGE_SIZE - 1)
 
@@ -15,14 +20,73 @@
 #define TO_PAGE_SIZE(x) ((x + (PAGE_MASK)) & ~(PAGE_MASK))
 
 
-#ifdef __cplusplus
-extern "C" {
-#endif
+extern "C" void dprintf(const char *format, ...);
 
-void dprintf(const char *format, ...);
 
-#ifdef __cplusplus
+namespace utility {
+
+
+template<typename T>
+class vector {
+public:
+	inline			vector();
+
+			void	push_back(const T& value);
+			void	pop_back()	{ fSize--; }
+
+			T&		back()	{ return fData[fSize - 1]; }
+
+			T&		operator[](size_t idx)	{ return fData[idx]; }
+			const T&	operator[](size_t idx) const	{ return fData[idx]; }
+
+			size_t	size() const	{ return fSize; }
+			bool	empty() const	{ return size() == 0; }
+
+private:
+			void	_Grow();
+
+			size_t	fMaxSize;
+			size_t	fSize;
+			T*		fData;
+};
+
+
+template<typename T>
+vector<T>::vector()
+	:
+	fMaxSize(0),
+	fSize(0),
+	fData(NULL)
+{
 }
-#endif
+
+
+template<typename T>
+void
+vector<T>::push_back(const T& value)
+{
+	if (fSize + 1 > fMaxSize)
+		_Grow();
+	fData[fSize++] = value;
+}
+
+
+template<typename T>
+void
+vector<T>::_Grow()
+{
+	size_t newSize = std::max(fMaxSize * 2, size_t(4));
+	T* newBuffer = new T[newSize];
+	if (fSize > 0) {
+		memcpy(newBuffer, fData, fSize * sizeof(T));
+		delete[] fData;
+	}	
+	fData = newBuffer;
+	fMaxSize = newSize;
+}
+
+
+}	// namespace utility
+
 
 #endif	// UTILITY_H