1 /*

     2  * Low-level protocol support for the IPC connection to the engine.

     3  */

     4 

     5 #ifndef IPCCONN_H_

     6 #define IPCCONN_H_

     7 

     8 #include <stddef.h>

     9 

    10 typedef enum {IPC_NOT_CONNECTED, IPC_LISTENING, IPC_CONNECTED} IpcConnState;

    11 

    12 /**

    13  * Called by flib_init(). Initialize everything related to ipc.

    14  */

    15 void flib_ipcconn_init();

    16 

    17 /**

    18  * Called by flib_quit(). Free resources and shut down.

    19  */

    20 void flib_ipcconn_quit();

    21 

    22 /**

    23  * Start listening for a connection from the engine. The system has to be in state

    24  * IPC_NOT_CONNECTED when calling this function.

    25  *

    26  * Returns the port we started listening on, or a negative value if there is an error.

    27  *

    28  * We stop listening once a connection has been established, so if you want to start

    29  * the engine again and talk to it you need to call this function again after the old

    30  * connection is closed.

    31  */

    32 int flib_ipcconn_listen();

    33 

    34 /**

    35  * Close the current IPC connection and/or stop listening for an incoming one.

    36  * This also discards all unread messages.

    37  */

    38 void flib_ipcconn_close();

    39 

    40 /**

    41  * Determine the current connection state

    42  */

    43 IpcConnState flib_ipcconn_state();

    44 

    45 /**

    46  * Receive a single message (up to 255 bytes) and copy it into the data buffer.

    47  * Returns the length of the received message, a negative value if no message could

    48  * be read.

    49  */

    50 int flib_ipcconn_recv_message(void *data);

    51 

    52 /**

    53  * Write a single message (up to 255 bytes) to the engine. This call blocks until the

    54  * message is completely written or the connection is closed or an error occurs.

    55  *

    56  * Calling this function in a state other than IPC_CONNECTED will fail immediately.

    57  * Returns a negative value on failure.

    58  */

    59 int flib_ipcconn_send_message(void *data, size_t len);

    60 

    61 /**

    62  * Call regularly to allow background work to proceed

    63  */

    64 void flib_ipcconn_tick();

    65 

    66 #endif /* IPCCONN_H_ */

    67