initial commit, 4.5 stable

thirdparty/graphite/src/inc/Endian.h

@@ -0,0 +1,86 @@
+// SPDX-License-Identifier: MIT OR MPL-2.0 OR LGPL-2.1-or-later OR GPL-2.0-or-later
+// Copyright 2011, SIL International, All rights reserved.
+/*
+Description:
+    A set of fast template based decoders for decoding values of any C integer
+    type up to long int size laid out with most significant byte first or least
+    significant byte first (aka big endian or little endian).  These are CPU
+    byte order agnostic and will function the same regardless of the CPUs native
+    byte order.
+
+    Being template based means if the either le or be class is not used then
+    template code of unused functions will not be instantiated by the compiler
+    and thus shouldn't cause any overhead.
+*/
+
+#include <cstddef>
+
+#pragma once
+
+
+class be
+{
+    template<int S>
+    inline static unsigned long int _peek(const unsigned char * p) {
+        return _peek<S/2>(p) << (S/2)*8 | _peek<S/2>(p+S/2);
+    }
+public:
+    template<typename T>
+    inline static T peek(const void * p) {
+        return T(_peek<sizeof(T)>(static_cast<const unsigned char *>(p)));
+    }
+
+    template<typename T>
+    inline static T read(const unsigned char * &p) {
+        const T r = T(_peek<sizeof(T)>(p));
+        p += sizeof r;
+        return r;
+    }
+
+    template<typename T>
+    inline static T swap(const T x) {
+        return T(_peek<sizeof(T)>(reinterpret_cast<const unsigned char *>(&x)));
+    }
+
+    template<typename T>
+    inline static void skip(const unsigned char * &p, size_t n=1) {
+        p += sizeof(T)*n;
+    }
+};
+
+template<>
+inline unsigned long int be::_peek<1>(const unsigned char * p) { return *p; }
+
+
+class le
+{
+    template<int S>
+    inline static unsigned long int _peek(const unsigned char * p) {
+        return _peek<S/2>(p) | _peek<S/2>(p+S/2)  << (S/2)*8;
+    }
+public:
+    template<typename T>
+    inline static T peek(const void * p) {
+        return T(_peek<sizeof(T)>(static_cast<const unsigned char *>(p)));
+    }
+
+    template<typename T>
+    inline static T read(const unsigned char * &p) {
+        const T r = T(_peek<sizeof(T)>(p));
+        p += sizeof r;
+        return r;
+    }
+
+    template<typename T>
+    inline static T swap(const T x) {
+        return T(_peek<sizeof(T)>(reinterpret_cast<const unsigned char *>(&x)));
+    }
+
+    template<typename T>
+    inline static void skip(const unsigned char * &p, size_t n=1) {
+        p += sizeof(T)*n;
+    }
+};
+
+template<>
+inline unsigned long int le::_peek<1>(const unsigned char * p) { return *p; }