1 /* 2 * Copyright (c) 2015 Carlos Pizano-Uribe cpu@chromium.org 3 * 4 * Use of this source code is governed by a MIT-style 5 * license that can be found in the LICENSE file or at 6 * https://opensource.org/licenses/MIT 7 */ 8 #pragma once 9 10 #include <lk/compiler.h> 11 #include <sys/types.h> 12 13 __BEGIN_CDECLS 14 15 // Ports are named, opaque objects and come in three flavors, the 16 // write-side, the read-side and a port group which is a collection 17 // of read-side ports. 18 19 #define PORT_NAME_LEN 12 20 21 typedef void *port_t; 22 23 // A Port packet is wide enough to carry two full words of data 24 #define PORT_PACKET_LEN (sizeof(void *) * 2) 25 typedef struct { 26 char value[PORT_PACKET_LEN]; 27 } port_packet_t; 28 29 typedef struct { 30 void *ctx; 31 port_packet_t packet; 32 } port_result_t; 33 34 typedef enum { 35 PORT_MODE_BROADCAST = 0, 36 PORT_MODE_UNICAST = 1, 37 PORT_MODE_BIG_BUFFER = 2, 38 } port_mode_t; 39 40 // Inits the port subsystem 41 void port_init(void); 42 43 // Make a named write-side port. broadcast ports can be opened by any 44 // number of read-clients. |name| can be up to PORT_NAME_LEN chars. If 45 // the write port exists it is returned even if the |mode| does not match. 46 status_t port_create(const char *name, port_mode_t mode, port_t *port); 47 48 // Make a read-side port. Only non-destroyed existing write ports can 49 // be opened with this api. Unicast ports can only be opened once. For 50 // broadcast ports, each call if successful returns a new port. 51 status_t port_open(const char *name, void *ctx, port_t *port); 52 53 // Creates a read-side port group which behaves just like a regular 54 // read-side port. A given port can only be assoicated with one port group. 55 status_t port_group(port_t *ports, size_t count, port_t *group); 56 57 // Adds a read-side port to an existing port group. 58 status_t port_group_add(port_t group, port_t port); 59 60 // Removes a read-side port to an existing port group. 61 status_t port_group_remove(port_t group, port_t port); 62 63 // Write to a port |count| packets, non-blocking, all or none atomic success. 64 status_t port_write(port_t port, const port_packet_t *pk, size_t count); 65 66 // Read one packet from the port or port group, blocking. The |result| contains 67 // the port that the message was read from. If |timeout| is zero the call 68 // does not block. 69 status_t port_read(port_t port, lk_time_t timeout, port_result_t *result); 70 71 // Destroy the write-side port, flush queued packets and release all resources, 72 // all calls will now fail on that port. Only a closed port can be destroyed. 73 status_t port_destroy(port_t port); 74 75 // Close the read-side port or the write side port. A closed write side port 76 // can be opened and the pending packets read. closing a port group does not 77 // close the included ports. 78 status_t port_close(port_t port); 79 80 __END_CDECLS 81