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+// Copyright 2001 - 2003 Google Inc. All Rights Reserved
+
+#ifndef BASE_BASICTYPES_H__
+#define BASE_BASICTYPES_H__
+
+typedef unsigned char uint8;
+typedef unsigned short uint16;
+typedef unsigned int uint32;
+
+const uint8 kuint8max = (( uint8) 0xFF);
+const uint32 kuint32max = ((uint32) 0xFFFFFFFF);
+
+// The arraysize(arr) macro returns the # of elements in an array arr.
+// The expression is a compile-time constant, and therefore can be
+// used in defining new arrays, for example. If you use arraysize on
+// a pointer by mistake, you will get a compile-time error.
+//
+// One caveat is that arraysize() doesn't accept any array of an
+// anonymous type or a type defined inside a function. In these rare
+// cases, you have to use the unsafe ARRAYSIZE() macro below. This is
+// due to a limitation in C++'s template system. The limitation might
+// eventually be removed, but it hasn't happened yet.
+
+// This template function declaration is used in defining arraysize.
+// Note that the function doesn't need an implementation, as we only
+// use its type.
+template <typename T, size_t N>
+char (&ArraySizeHelper(T (&array)[N]))[N];
+
+// That gcc wants both of these prototypes seems mysterious. VC, for
+// its part, can't decide which to use (another mystery). Matching of
+// template overloads: the final frontier.
+#ifndef _MSC_VER
+template <typename T, size_t N>
+char (&ArraySizeHelper(const T (&array)[N]))[N];
+#endif
+
+#define arraysize(array) (sizeof(ArraySizeHelper(array)))
+
+// ARRAYSIZE performs essentially the same calculation as arraysize,
+// but can be used on anonymous types or types defined inside
+// functions. It's less safe than arraysize as it accepts some
+// (although not all) pointers. Therefore, you should use arraysize
+// whenever possible.
+//
+// The expression ARRAYSIZE(a) is a compile-time constant of type
+// size_t.
+//
+// ARRAYSIZE catches a few type errors. If you see a compiler error
+//
+// "warning: division by zero in ..."
+//
+// when using ARRAYSIZE, you are (wrongfully) giving it a pointer.
+// You should only use ARRAYSIZE on statically allocated arrays.
+//
+// The following comments are on the implementation details, and can
+// be ignored by the users.
+//
+// ARRAYSIZE(arr) works by inspecting sizeof(arr) (the # of bytes in
+// the array) and sizeof(*(arr)) (the # of bytes in one array
+// element). If the former is divisible by the latter, perhaps arr is
+// indeed an array, in which case the division result is the # of
+// elements in the array. Otherwise, arr cannot possibly be an array,
+// and we generate a compiler error to prevent the code from
+// compiling.
+//
+// Since the size of bool is implementation-defined, we need to cast
+// !(sizeof(a) & sizeof(*(a))) to size_t in order to ensure the final
+// result has type size_t.
+//
+// This macro is not perfect as it wrongfully accepts certain
+// pointers, namely where the pointer size is divisible by the pointee
+// size. Since all our code has to go through a 32-bit compiler,
+// where a pointer is 4 bytes, this means all pointers to a type whose
+// size is 3 or greater than 4 will be (righteously) rejected.
+//
+// Starting with Visual C++ 2005, WinNT.h includes ARRAYSIZE.
+#define ARRAYSIZE_UNSAFE(a) \
+ ((sizeof(a) / sizeof(*(a))) / \
+ static_cast<size_t>(!(sizeof(a) % sizeof(*(a)))))
+
+// A macro to disallow the evil copy constructor and operator= functions
+// This should be used in the private: declarations for a class
+#define DISALLOW_EVIL_CONSTRUCTORS(TypeName) \
+ TypeName(const TypeName&); \
+ void operator=(const TypeName&)
+
+#endif // BASE_BASICTYPES_H__