1 files changed, 96 insertions, 0 deletions
diff --git a/Source/Particles/ElementaryProcess/QEDInternals/QedTableParserHelperFunctions.H b/Source/Particles/ElementaryProcess/QEDInternals/QedTableParserHelperFunctions.H
new file mode 100644
index 000000000..dd66f626f
--- /dev/null
+++ b/Source/Particles/ElementaryProcess/QEDInternals/QedTableParserHelperFunctions.H
@@ -0,0 +1,96 @@
+/* Copyright 2019 Luca Fedeli, Maxence Thevenet
+ *
+ * This file is part of WarpX.
+ *
+ * License: BSD-3-Clause-LBNL
+ */
+#ifndef WARPX_amrex_qed_table_parser_helper_functions_h_
+#define WARPX_amrex_qed_table_parser_helper_functions_h_
+
+/**
+ * This header contains helper functions to safely extract data
+ * (e.g. integers, floating point numbers) from raw binary data
+ * (i.e. a char*) and to convert arrays into raw binary data.
+ */
+
+#include <AMReX_Vector.H>
+#include <tuple>
+
+namespace QedUtils{
+    /**
+    * This function safely extracts an amrex::Vector<T> from raw binary data.
+    * T must be a simple datatype (e.g. an int, a float, a double...).
+    *
+    * @param[in] p_data a pointer to the binary stream
+    * @param[in] how_many how many T should be read from stream
+    * @param[in] p_last a pointer to the last element of the char* array
+    * @return {a tuple containing
+    * 1) flag (which is false if p_last is exceeded)
+    * 2) a Vector of T
+    * 3) a pointer to a new location of the binary data (after having read how_many T)}
+    */
+    template <class T>
+    std::tuple<bool, amrex::Vector<T>, const char*>parse_raw_data_vec(
+        const char* p_data, size_t how_many, const char* const p_last)
+    {
+        amrex::Vector<T> res;
+        if(p_data + sizeof(T)*how_many > p_last)
+            return std::make_tuple(false, res, nullptr);
+
+        auto r_data = reinterpret_cast<const T*>(p_data);
+
+        res.assign(r_data, r_data + how_many);
+
+        p_data += sizeof(T)*how_many;
+        return std::make_tuple(true, res, p_data);
+    }
+
+    /**
+    * This function safely extracts a T from raw binary data.
+    * T must be a simple datatype (e.g. an int, a float, a double...).
+    *
+    * @param[in] p_data a pointer to the binary stream
+    * @param[in] p_last a pointer to the last element of the char* array
+    * @return {a tuple containing
+    * 1) flag (which is false if p_last is exceeded)
+    * 2) a T
+    * 3) a pointer to a new location of the binary data (after having read 1 T)}
+    */
+    template <class T>
+    std::tuple<bool, T, const char*> parse_raw_data(
+        const char* p_data, const char* const p_last)
+    {
+        T res;
+        if(p_data + sizeof(T) > p_last)
+            return std::make_tuple(false, res, nullptr);
+
+        auto r_data = reinterpret_cast<const T*>(p_data);
+
+        res = *r_data;
+
+        p_data += sizeof(T);
+        return std::make_tuple(true, res, p_data);
+    }
+
+    /**
+    * This function converts a C-style array of T into
+    * a Vector<char> (i.e. raw binary data) and adds it
+    * to an existing Vector<char> passed by reference
+    * @param[in] p_data a pointer to the beginning of the array
+    * @param[in] how_many number of elements of type T in the array
+    * @param[in,out] raw_data data will be appended to this vector
+    */
+    template <class T>
+    void add_data_to_vector_char (
+        const T* p_data, size_t how_many, amrex::Vector<char>& raw_data)
+    {
+        raw_data.insert(
+            raw_data.end(),
+            reinterpret_cast<const char*>(p_data),
+            reinterpret_cast<const char*>(p_data) +
+            sizeof(T)*how_many
+        );
+    }
+};
+
+#endif //WARPX_amrex_qed_table_parser_helper_functions_h_