j1939-vehicle-position-srv: Introduce J1939 and NMEA 2000 Vehicle Position Server

This patch adds `j1939-vehicle-position-srv`, a server for sending
vehicle position data over CAN using J1939 or NMEA 2000 protocols. It
retrieves GPS data from gpsd or simulates data if gpsd is unavailable.
By default, it operates in J1939 profile but can switch to NMEA 2000
with the `-p nmea2000` option.

Usage Examples:
1. With gpsd:
   j1939acd -r 64-95 -c /tmp/1122334455667789.jacd 1122334455667789 vcan0 &
   j1939-vehicle-position-srv -i vcan0 -n 0x1122334455667789

2. In simulation mode without gpsd:
   j1939-vehicle-position-srv -i vcan0 -s -p nmea2000

Signed-off-by: Oleksij Rempel <linux@rempel-privat.de>

.github/workflows/compile.yml

@@ -30,7 +30,10 @@ jobs:
         podman run --name stable -di --userns=keep-id:uid=1000,gid=1000 -v "$PWD":/home -w /home ${{ matrix.release }} bash
         podman exec -i stable uname -a
         podman exec -i stable id
+        podman exec -i -u root stable dpkg --add-architecture arm64
+        podman exec -i -u root stable dpkg --add-architecture armhf
         podman exec -i -u root stable apt update
+        podman exec -e DEBIAN_FRONTEND='noninteractive' -i -u root stable apt upgrade -o APT::Install-Suggests=false -qy
         podman exec -e DEBIAN_FRONTEND='noninteractive' -i -u root stable apt install -o APT::Install-Suggests=false -qy ${release} \
                 clang \
                 cmake \
@@ -38,6 +41,9 @@ jobs:
                 gcc-aarch64-linux-gnu \
                 gcc-arm-linux-gnueabihf \
                 gcc-mips-linux-gnu \
+                libgps-dev \
+                libgps-dev:arm64 \
+                libgps-dev:armhf \
                 make
 
     - name: Configure & Build with gcc

CMakeLists.txt

@@ -67,6 +67,10 @@ set(PROGRAMS_J1939_TIMEDATE
   j1939-timedate-cli
 )
 
+set(PROGRAMS_J1939_VEHICLE_POSITION
+  j1939-vehicle-position-srv
+)
+
 set(PROGRAMS_ISOBUSFS
   isobusfs-srv
   isobusfs-cli
@@ -190,6 +194,22 @@ if(NOT ANDROID)
     j1939-timedate-srv
     DESTINATION ${CMAKE_INSTALL_BINDIR})
 
+  set(PUBLIC_HEADER_J1939_VEHICLE_POSITION
+    j1939_vehicle_position/j1939_vehicle_position_cmn.h
+  )
+
+  add_executable(j1939-vehicle-position-srv
+    j1939_vehicle_position/j1939_vehicle_position_srv.c
+  )
+
+  target_link_libraries(j1939-vehicle-position-srv
+    PRIVATE can j1939 gps
+  )
+
+  install(TARGETS
+    j1939-vehicle-position-srv
+    DESTINATION ${CMAKE_INSTALL_BINDIR})
+
 endif()
 
 add_library(can STATIC

Makefile

@@ -67,6 +67,9 @@ PROGRAMS_J1939_TIMEDATE := \
 	j1939-timedate-srv \
 	j1939-timedate-cli
 
+PROGRAMS_J1939_VEHICLE_POSITION := \
+	j1939-vehicle-position-srv
+
 PROGRAMS_ISOBUSFS := \
 	isobusfs-srv \
 	isobusfs-cli
@@ -98,6 +101,7 @@ PROGRAMS_SLCAN := \
 PROGRAMS := \
 	$(PROGRAMS_CANGW) \
 	$(PROGRAMS_J1939_TIMEDATE) \
+	$(PROGRAMS_J1939_VEHICLE_POSITION) \
 	$(PROGRAMS_ISOBUSFS) \
 	$(PROGRAMS_ISOTP) \
 	$(PROGRAMS_J1939) \
@@ -126,7 +130,8 @@ endif
 all: $(PROGRAMS)
 
 clean:
-	rm -f $(PROGRAMS) *.o mcp251xfd/*.o isobusfs/*.o j1939_timedate/*.o
+	rm -f $(PROGRAMS) *.o mcp251xfd/*.o isobusfs/*.o j1939_timedate/*.o \
+		j1939_vehicle_position/*.o
 
 install:
 	mkdir -p $(DESTDIR)$(PREFIX)/bin
@@ -153,6 +158,8 @@ isobusfs_srv.o:	lib.h libj1939.h
 isobusfs_c.o:	lib.h libj1939.h
 j1939_timedate_srv.o: lib.h libj1939.h
 j1939_timedate_cli.o: lib.h libj1939.h
+j1939_vehicle_position_srv.o: lib.h libj1939.h
+
 canframelen.o:  canframelen.h
 
 asc2log:	asc2log.o	lib.o
@@ -182,6 +189,12 @@ j1939-timedate-cli:	lib.o \
 			j1939_timedate/j1939_timedate_cli.o
 		$(CC) $(LDFLAGS) $^ $(LDLIBS) -o $@
 
+j1939-vehicle-position-srv: \
+			lib.o \
+			libj1939.o \
+			j1939_vehicle_position/j1939_vehicle_position_srv.o \
+		$(CC) $(LDFLAGS) $^ $(LDLIBS) -lgps -o $@
+
 isobusfs-srv:	lib.o \
 		libj1939.o \
 		isobusfs/isobusfs_cmn.o \

libj1939.c

@@ -253,6 +253,31 @@ int libj1939_bind_socket(int sock, struct sockaddr_can *addr)
 	return 0;
 }
 
+/**
+ * libj1939_connect_socket - Connects a socket to a CAN address.
+ * @sock: The socket file descriptor.
+ * @addr: The CAN address to connect to.
+ *
+ * This function attempts to establish a connection between the given socket
+ * and the specified CAN address. If the connection fails, it logs an error
+ * message with the error code and a description of the error.
+ *
+ * Return: 0 on success, or a negative error code on failure.
+ */
+int libj1939_connect_socket(int sock, struct sockaddr_can *addr)
+{
+	int ret;
+
+	ret = connect(sock, (void *)addr, sizeof(*addr));
+	if (ret < 0) {
+		ret = -errno;
+		pr_err("failed to connect socket: %d (%s)", ret, strerror(ret));
+		return ret;
+	}
+
+	return 0;
+}
+
 /**
  * libj1939_socket_prio - Set the priority of a J1939 socket
  * @sock: The file descriptor of the socket

libj1939.h

@@ -42,6 +42,7 @@ void libj1939_init_sockaddr_can(struct sockaddr_can *sac, uint32_t pgn);
 
 int libj1939_open_socket(void);
 int libj1939_bind_socket(int sock, struct sockaddr_can *addr);
+int libj1939_connect_socket(int sock, struct sockaddr_can *addr);
 int libj1939_socket_prio(int sock, int prio);
 int libj1939_set_broadcast(int sock);
 int libj1939_add_socket_to_epoll(int epoll_fd, int sock, uint32_t events);