+/** Options for read operations
+ *
+ * This is a set of flags managed with bitwise operators. Only the
+ * meaningful operations are defined: addition, conversions to/from
+ * integers are not allowed.
+ */
+class ReadOptions {
+ std::uint32_t value_;
+ constexpr explicit ReadOptions(std::uint32_t value) : value_(value) {}
+public:
+ constexpr ReadOptions() : value_(0) {}
+
+ constexpr operator bool() const { return value_ != 0; }
+ constexpr bool operator!() const { return value_ == 0; }
+
+ constexpr ReadOptions operator|(ReadOptions const& that) const
+ {
+ return ReadOptions(value_ | that.value_);
+ }
+ constexpr ReadOptions operator&(ReadOptions const& that) const
+ {
+ return ReadOptions(value_ & that.value_);
+ }
+ constexpr ReadOptions operator^(ReadOptions const& that) const
+ {
+ return ReadOptions(value_ ^ that.value_);
+ }
+ constexpr ReadOptions operator~() const
+ {
+ return ReadOptions(~value_);
+ }
+
+ ReadOptions& operator|=(ReadOptions const& that)
+ {
+ value_ |= that.value_;
+ return *this;
+ }
+ ReadOptions& operator&=(ReadOptions const& that)
+ {
+ value_ &= that.value_;
+ return *this;
+ }
+ ReadOptions& operator^=(ReadOptions const& that)
+ {
+ value_ &= that.value_;
+ return *this;
+ }
+
+ /** Copy the data to the given buffer */
+ static constexpr ReadOptions none() { return ReadOptions(0); }
+
+ /** Allows to return a pointer to another buffer where the data is
+ * available instead of copying the data into the buffer
+ */
+ static constexpr ReadOptions lazy() { return ReadOptions(1); }
+};
+
+/** A given state of a given process (abstract base class)
+ *
+ * Currently, this might either be:
+ *
+ * * the current state of an existing process;
+ *
+ * * a snapshot.
+ *
+ * In order to support SMPI privatization, the can read the memory from the
+ * context of a given SMPI process: if specified, the code reads data from the
+ * correct SMPI privatization VMA.
+ */