RIL Socket 资源创建

service ril-daemon /system/bin/rild

class main
    socket rild stream 660 root radio
    socket sap_uim_socket1 stream 660 bluetooth bluetooth
    socket rild-debug stream 660 radio system
    user root

group radio cache inet misc audio log

radiooptions.c 解析：

int main(int argc, char *argv[])
{
    int fd;
    int num_socket_args = 0;
    int i  = 0;
    int modem_socket_type = 0;
    int sim_id = 0;
    char socket_name[20];

if(error_check(argc, argv)) {
        print_usage();
        exit(-1);
    }

num_socket_args = get_number_args(argv);  // 执行参数个数

modem_socket_type = atoi(argv[(num_socket_args-1)]);  //The last argument must be modem-socket style \n\

sim_id = atoi(argv[(num_socket_args-2)]);  // The argument before the last one must be SIM slot \n\

memset(socket_name, 0, sizeof(char)*20);    
    if (sim_id == 0 || modem_socket_type == 1) {
        strncpy(socket_name, SOCKET_NAME_RIL_DEBUG, 19);
    } else if (sim_id == 1) {
        strncpy(socket_name, SOCKET_NAME_RIL2_DEBUG, 19);
    }
    
    fd = socket_local_client(socket_name,
                                 ANDROID_SOCKET_NAMESPACE_RESERVED,
                                 SOCK_STREAM);
    if (fd < 0) {
        perror ("opening radio debug socket");
        exit(-1);
    }
    
    /* It is not necessacry to pass the argument "modem-socket style" to rild */

最后一个参数modem-socket style 不需要发送到rild 进程

num_socket_args--;  // 将参数个数减1
    int ret = send(fd, (const void *)&num_socket_args, sizeof(int), 0);  //发送参数个数
    if(ret != sizeof(int)) {
        perror ("Socket write error when sending num args");
        close(fd);
        exit(-1);
    }

for (i = 0; i < num_socket_args; i++) {  //将参数发送到rild 进程
        // Send length of the arg, followed by the arg.
        int len = strlen(argv[1 + i]);     //获取每个参数的长度，并发送
        ret = send(fd, &len, sizeof(int), 0);
        if (ret != sizeof(int)) {
            perror("Socket write Error: when sending arg length");
            close(fd);
            exit(-1);
        }

ret = send(fd, argv[1 + i], sizeof(char) * len, 0);    //发送每个参数的值
        if (ret != len * sizeof(char)) {
            perror ("Socket write Error: When sending arg");
            close(fd);
            exit(-1);
        }
    }

close(fd);
    return 0;
}

编译radiooptions.c ，生成mtkradiooptions 可执行文件；

push 到手机 system/bin ，添加可执行权限：chmod 777 /system/bin/mtkradiooptions

执行如下：

mtkradiooptions  1  1  1  ；关闭radio

mtkradiooptions  5  1  1  ；打开radio

Native 端Ril.cpp ，以 rild-debug socket 讲解

extern "C" void
RIL_register (const RIL_RadioFunctions *callbacks) {

s_fdDebug = android_get_control_socket(rildebug);//获取ril-debug socket 描述符
    if (s_fdDebug < 0) {
        RLOGE("Failed to get socket : %s errno:%d", rildebug, errno);
        exit(-1);
    }

ret = listen(s_fdDebug, 4);//监听ril-debug socket

if (ret < 0) {
        RLOGE("Failed to listen on ril debug socket '%d': %s",
             s_fdDebug, strerror(errno));
        exit(-1);
    }

ril_event_set (&s_debug_event, s_fdDebug, true,
                debugCallback, NULL); //传递socket 文件描述符，debugCallback 处理接收到的消息

}

static void debugCallback (int fd, short flags, void *param) {

acceptFD = accept (fd,  (sockaddr *) &peeraddr, &socklen);   // 接收socket 连接

if (acceptFD < 0) {
        RLOGE ("error accepting on debug port: %d\n", errno);     
        return;
    }

if (recv(acceptFD, &number, sizeof(int), 0) != sizeof(int)) {     // 接收第一个数据（参数的个数）请求
        RLOGE ("error reading on socket: number of Args: \n");
        return;
    }

args[i] = (char *) calloc(1, (sizeof(char) * len) + 1);     // 接收参数数据
        if (recv(acceptFD, args[i], sizeof(char) * len, 0)
            != (int)sizeof(char) * len) {
            RLOGE ("error reading on socket: Args[%d] \n", i);
            freeDebugCallbackArgs(i, args);
            return;
        }

}

static void
issueLocalRequest(int request, void *data, int len, RIL_SOCKET_ID socket_id) {

pRI->p_next = *pendingRequestsHook;
    *pendingRequestsHook = pRI;

callOnRequest(request, data, len, pRI, pRI->socket_id);

}