#include <cstring>
#include <type_traits>
+#include <string>
+#include <vector>
+
#include "src/mc/mc_forward.hpp"
#include "src/mc/RemotePtr.hpp"
namespace simgrid {
namespace mc {
-/** Process index used when no process is available
+/** Process index used when no process is available (SMPI privatization)
*
- * The expected behaviour is that if a process index is needed it will fail.
+ * The expected behavior is that if a process index is needed it will fail.
* */
const int ProcessIndexMissing = -1;
-/** Process index used when we don't care about the process index
+/** Process index used when we don't care about the process index (SMPI privatization)
* */
const int ProcessIndexDisabled = -2;
-/** Constant used when any process will do.
+/** Constant used when any process will do (SMPI privatization)
*
- * This is is index of the first process.
+ * Note: This is is index of the first process.
*/
const int ProcessIndexAny = 0;
static constexpr ReadOptions lazy() { return ReadOptions(1); }
};
-/** A value from another process
- *
- * This represents a value from another process:
- *
- * * constructor/destructor are disabled;
- *
- * * raw memory copy (std::memcpy) is used to copy Remote<T>;
- *
- * * raw memory comparison is used to compare them;
- *
- * * when T is a trivial type, Remote is convertible to a T.
- *
- * We currently only handle the case where the type has the same layout
- * in the current process and in the target process: we don't handle
- * cross-architecture (such as 32-bit/64-bit access).
- */
-template<class T>
-class Remote {
-private:
- // If we use a union, it won't work with abstract types:
- char buffer[sizeof(T)];
-public:
- // HACK, some code currently cast this to T* which is **not** legal.
- void* data() { return buffer; }
- const void* data() const { return buffer; }
- constexpr std::size_t size() const { return sizeof(T); }
- operator T() const {
- static_assert(std::is_trivial<T>::value, "Cannot convert non trivial type");
- T res;
- std::memcpy(&res, buffer, sizeof(T));
- return res;
- }
- Remote() {}
- Remote(T const& x)
- {
- std::memcpy(&x, buffer, sizeof(T));
- }
- Remote& operator=(T const& x)
- {
- std::memcpy(&x, buffer, sizeof(T));
- }
-};
-
/** 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.
*/
class AddressSpace {
private:
AddressSpace(Process* process) : process_(process) {}
virtual ~AddressSpace();
+ /** The process of this addres space
+ *
+ * This is where we can get debug informations, memory layout, etc.
+ */
simgrid::mc::Process* process() const { return process_; }
/** Read data from the address space
*
* @param buffer target buffer for the data
- * @param size number of bytes
+ * @param size number of bytes to read
* @param address remote source address of the data
* @param process_index which process (used for SMPI privatization)
* @param options
/** Read a given data structure from the address space */
template<class T> inline
- void read(T *buffer, RemotePtr<T> ptr, int process_index = ProcessIndexAny)
+ void read(T *buffer, RemotePtr<T> ptr, int process_index = ProcessIndexAny) const
{
this->read_bytes(buffer, sizeof(T), ptr, process_index);
}
template<class T> inline
- void read(Remote<T>& buffer, RemotePtr<T> ptr, int process_index = ProcessIndexAny)
+ void read(Remote<T>& buffer, RemotePtr<T> ptr, int process_index = ProcessIndexAny) const
{
- this->read_bytes(buffer.data(), sizeof(T), ptr, process_index);
+ this->read_bytes(buffer.getBuffer(), sizeof(T), ptr, process_index);
}
- /** Read a given data structure from the address space */
+ /** Read a given data structure from the addres space
+ *
+ * This version returns by value.
+ */
template<class T> inline
- Remote<T> read(RemotePtr<T> ptr, int process_index = ProcessIndexMissing)
+ Remote<T> read(RemotePtr<T> ptr, int process_index = ProcessIndexMissing) const
{
Remote<T> res;
this->read_bytes(&res, sizeof(T), ptr, process_index);
return res;
}
+
+ /** Read a string of known size */
+ std::string read_string(RemotePtr<char> address, std::size_t len) const
+ {
+ // TODO, use std::vector with .data() in C++17 to avoid useless copies
+ std::vector<char> buffer(len);
+ buffer[len] = '\0';
+ this->read_bytes(buffer.data(), len, address);
+ return std::string(buffer.data(), buffer.size());
+ }
+
};
}
