(#18) Moved inline functions to a separate header

Moved a bunch of inline function to a separate `api_impl.h` header to
avoid polluting too much the main header.

src/papi/lz4/api.h

@@ -78,59 +78,6 @@ namespace lz4 { namespace api {
 };
 };
 
-namespace lz4 { namespace api {
-
-    inline int compressBound(int inputSize)
-        {
-        return _detail::LZ4_compressBound(inputSize);
-        };
-
-    inline int compressBound(const span<char> input)
-        {
-        return _detail::LZ4_compressBound(input.length());
-        };
-
-    inline int compress_default(const span<char> source, span<char> dest)
-        {
-        return _detail::LZ4_compress_default(source.data(), dest.data(), source.length(), dest.length());
-        };
-
-    inline int decompress_safe (const span<char> source, span<char>  dest)
-        {
-        return _detail::LZ4_decompress_safe(source.data(), dest.data(), source.length(), dest.length());
-        };
-
-    inline int sizeofState()
-        {
-        return _detail::LZ4_sizeofState();
-        };
-
-    inline int compress_fast_extState(span<byte> state, const span<char> source, span<char> dest, int acceleration)
-        {
-        return _detail::LZ4_compress_fast_extState(state.data(), source.data(), dest.data(), source.length(), dest.length(), acceleration);
-        };
-
-    inline int compress_destSize (span<char>& source, span<char> dest)
-        {
-        auto sourceSize = source.length();
-        volatile int sourceUsed = sourceSize;
-        auto atExit = finally([&](){
-            source = source.subspan(sourceSize - sourceUsed);
-        });
-
-        return _detail::LZ4_compress_destSize(source.data(), dest.data(), const_cast<int*>(&sourceUsed), dest.length());
-        };
-
-    inline int decompress_fast (const span<char> source, span<char> dest, int uncompressedSize)
-        {
-        return _detail::LZ4_decompress_fast(source.data(), dest.data(), uncompressedSize);
-        };
-
-    inline int decompress_safe_partial (const span<char> source, span<char> dest, int targetOutputSize)
-        {
-        return _detail::LZ4_decompress_safe_partial (source.data(), dest.data(), source.length(), targetOutputSize, dest.length());    
-        };    
-};
-};
+#include "api_impl.h"
 
 #endif // __CINT_LZ4_API__

src/papi/lz4/api_impl.h

@@ -0,0 +1,57 @@
+#pragma once
+
+
+namespace lz4 { namespace api {
+
+    inline int compressBound(int inputSize)
+        {
+        return _detail::LZ4_compressBound(inputSize);
+        };
+
+    inline int compressBound(const span<char> input)
+        {
+        return _detail::LZ4_compressBound(input.length());
+        };
+
+    inline int compress_default(const span<char> source, span<char> dest)
+        {
+        return _detail::LZ4_compress_default(source.data(), dest.data(), source.length(), dest.length());
+        };
+
+    inline int decompress_safe (const span<char> source, span<char>  dest)
+        {
+        return _detail::LZ4_decompress_safe(source.data(), dest.data(), source.length(), dest.length());
+        };
+
+    inline int sizeofState()
+        {
+        return _detail::LZ4_sizeofState();
+        };
+
+    inline int compress_fast_extState(span<byte> state, const span<char> source, span<char> dest, int acceleration)
+        {
+        return _detail::LZ4_compress_fast_extState(state.data(), source.data(), dest.data(), source.length(), dest.length(), acceleration);
+        };
+
+    inline int compress_destSize (span<char>& source, span<char> dest)
+        {
+        auto sourceSize = source.length();
+        volatile int sourceUsed = sourceSize;
+        auto atExit = finally([&](){
+            source = source.subspan(sourceSize - sourceUsed);
+        });
+
+        return _detail::LZ4_compress_destSize(source.data(), dest.data(), const_cast<int*>(&sourceUsed), dest.length());
+        };
+
+    inline int decompress_fast (const span<char> source, span<char> dest, int uncompressedSize)
+        {
+        return _detail::LZ4_decompress_fast(source.data(), dest.data(), uncompressedSize);
+        };
+
+    inline int decompress_safe_partial (const span<char> source, span<char> dest, int targetOutputSize)
+        {
+        return _detail::LZ4_decompress_safe_partial (source.data(), dest.data(), source.length(), targetOutputSize, dest.length());    
+        };    
+};
+};