Global Namespace

Overview

// namespaces

namespace rgpot;
    namespace rgpot::cache;
    namespace rgpot::types;
        namespace rgpot::types::adapt;
            namespace rgpot::types::adapt::capnp;
            namespace rgpot::types::adapt::eigen;
            namespace rgpot::types::adapt::xtensor;

// typedefs

typedef struct PotClient PotClient;

// classes

class AtomMatrix;
class GenericPotImpl;
class PotClient;

// global functions

void c_force_eam(int* natms, int ndim, double* box, double* R, double* F, double* U);
PotClient* pot_client_init(const char* host, int32_t port);
void pot_client_free(PotClient* client);
int32_t pot_calculate(PotClient* client, int32_t natoms, const double* pos, const int32_t* atmnrs, const double* box, double* out_energy, double* out_forces);
const char* pot_get_last_error(PotClient* client);
PotClient* pot_client_init(const char* host, int32_t port);
void pot_client_free(PotClient* client);
int32_t pot_calculate(PotClient* client, int32_t natoms, const double* pos, const int32_t* atmnrs, const double* box, double* out_energy, double* out_forces);
const char* pot_get_last_error(PotClient* client);
int main(int argc, char* argv[]);

// macros

#define CATCH_AND_REPORT(client, default_ret)

Detailed Documentation

Typedefs

typedef struct PotClient PotClient

C API for the RPC potential client bridge.

This header provides a C-compatible interface to the distributed potential calculation client, allowing integration with Fortran or other languages with a C interface, e.g. Julia.

Opaque handle to the client context.

Global Functions

void c_force_eam(int* natms, int ndim, double* box, double* R, double* F, double* U)

C-linkage bridge to the Fortran EAM implementation.

Parameters:

natms

Array containing counts of Cu and H atoms.

ndim

Total dimensions (3 * N).

box

Diagonal box vectors (assumes cubic).

R

Pointer to flat position array.

F

Pointer to output force array.

U

Pointer to output energy value.

Returns:

Void.

PotClient* pot_client_init(const char* host, int32_t port)

Initializes the RPC client connection.

Constructs a string-based address from the host and port, then initializes a new capnp::EzRpcClient. The main capability is cast to the Potential interface defined in the schema.

Note

Returns nullptr if the connection cannot be established or if the address is malformed.

void pot_client_free(PotClient* client)

Frees all resources associated with the client.

Performs a standard delete on the client pointer. This triggers the PotClient destructor, which cleans up the unique_ptr and associated RPC state.

int32_t pot_calculate(PotClient* client, int32_t natoms, const double* pos, const int32_t* atmnrs, const double* box, double* out_energy, double* out_forces)

Executes a remote potential calculation.

This function performs the following steps:

  1. Resets the last_error buffer.

  2. Initializes a calculation request.

  3. Maps the input pointers to kj::arrayPtr views to avoid unnecessary copying before serialization.

  4. Waits for the RPC promise to resolve.

  5. Validates the size of the returned force array.

  6. Copies the results into the provided output buffers.

Warning

The server must return a force array matching natoms * 3. If the sizes do not match, a non-zero error code is returned.

const char* pot_get_last_error(PotClient* client)

Retrieves the most recent error message.

Checks if a valid client handle is provided and if the last_error buffer contains data. If no error is recorded, an empty string is returned.

PotClient* pot_client_init(const char* host, int32_t port)

Initializes the RPC client connection.

Constructs a string-based address from the host and port, then initializes a new capnp::EzRpcClient. The main capability is cast to the Potential interface defined in the schema.

Note

Returns nullptr if the connection cannot be established or if the address is malformed.

Parameters:

host

Target server hostname or IP address.

port

Network port of the potential server.

Returns:

Pointer to the client context or NULL on failure.

See also:

pot_get_last_error

void pot_client_free(PotClient* client)

Frees all resources associated with the client.

Performs a standard delete on the client pointer. This triggers the PotClient destructor, which cleans up the unique_ptr and associated RPC state.

Parameters:

client

The opaque client handle to release.

Returns:

Void.

int32_t pot_calculate(PotClient* client, int32_t natoms, const double* pos, const int32_t* atmnrs, const double* box, double* out_energy, double* out_forces)

Executes a remote potential calculation.

The client must be successfully initialized.

This function performs the following steps:

  1. Resets the last_error buffer.

  2. Initializes a calculation request.

  3. Maps the input pointers to kj::arrayPtr views to avoid unnecessary copying before serialization.

  4. Waits for the RPC promise to resolve.

  5. Validates the size of the returned force array.

  6. Copies the results into the provided output buffers.

Warning

The server must return a force array matching natoms * 3. If the sizes do not match, a non-zero error code is returned.

Parameters:

client

The opaque client handle.

natoms

Total number of atoms in the system.

pos

Array of flattened atomic coordinates.

atmnrs

Array of atomic numbers.

box

Simulation cell vectors in row-major order.

out_energy

Pointer to store the calculated energy.

out_forces

Buffer to store the calculated forces.

Returns:

0 on success, non-zero on failure.

const char* pot_get_last_error(PotClient* client)

Retrieves the most recent error message.

Checks if a valid client handle is provided and if the last_error buffer contains data. If no error is recorded, an empty string is returned.

Parameters:

client

The opaque client handle.

Returns:

String containing the error description.

int main(int argc, char* argv[])

The main entry point handles command-line arguments to specify the network port and the potential type. It instantiates the requested physics engine and blocks until the server is terminated.

Usage

````./potserv <port> <PotentialType>

Parameters:

argc

Argument count.

argv

Argument vector.

Returns:

0 on success, 1 on initialization failure.