本章简单讲述下android实现自动拨号的功能,该功能利用了系统启动的rild的服务来实现,因为rild的服务是杀不死的,所以利用这一点,可以使拨号失败或网络断掉后自动重拨,来增强上网的可靠性。这里只实现拨号功能,把ril库实现的一些功能都去掉了。
一、修改rild程序源码
把 .../hardware/ril里面的文件全部删掉,创建rild文件夹,把以下面代码放到新建的文件夹下。
1、rild.c
#define LOG_TAG "RILD" #include <unistd.h> #include <pthread.h> #include <utils/Log.h> #include <sys/types.h> #include <sys/stat.h> #include "ril_fun.h" int main(int argc, char *argv[]) { int opt; int err; pthread_t tid; char buf[PROPERTY_VALUE_MAX]; static int device_fd; static char * device_path = NULL; umask(S_IRGRP | S_IWGRP | S_IXGRP | S_IROTH | S_IWOTH | S_IXOTH); while ( -1 != (opt = getopt(argc, argv, "d:"))) {//用来分析main函数传递的命令行参数 switch (opt) { case 'd': device_path = optarg; ALOGD("Opening tty device %s\n", device_path); break; default: ALOGD("Not tty device"); goto done; } } device_fd = device_open(device_path);//打开设备节点 device_init(device_fd);//初始化设备节点 property_set("ctl.stop", PPPD_SERVICE_NAME);//设置pppd_gprs属性为停止 request_setup_datacall(device_fd);//继续执行拨号 pthread_create(&tid,NULL,ip_detection,(void *)device_fd);//创建查询IP线程,使断网后重新拨号 done: while(1){ sleep(0x00ffffff); } return 0; }
2、ril_fun.c
#define LOG_TAG "RIL" #include <stdio.h> #include <string.h> #include <stdlib.h> #include <sys/types.h> #include <sys/stat.h> #include <fcntl.h> #include <termios.h> #include <sys/select.h> #include "ril_fun.h" #define PPPD_EXIT_CODE "net.gprs.ppp-exit" #define PPP_NET_LOCAL_IP "net.ppp0.local-ip" #define PPP_SYSFS_RETRY 5 #define PPP_OPERSTATE_PATH "/sys/class/net/ppp0/operstate" static int pppd_started = 0; int device_open(char *device_path) { int device_fd = -1; while (device_fd < 0) { if (device_path != NULL) { device_fd = open (device_path, O_RDWR);//打开串口AT模块的设备 } if (device_fd < 0) { ALOGD ("opening AT interface. retrying..."); sleep(3); } } return device_fd; } void device_init(int device_fd) { struct termios options; tcgetattr(device_fd, &options);//获取串口属性 cfsetispeed(&options, B115200);//设置接收波特率 cfsetospeed(&options, B115200);//设置发送波特率 options.c_iflag &= ~(IGNBRK|BRKINT|PARMRK|ISTRIP|IGNCR|ICRNL|IXON); options.c_cflag &= ~PARENB; //无奇偶校验位 options.c_cflag &= ~CSTOPB; //停止位为1位 options.c_cflag &= ~CSIZE; options.c_cflag |= CS8; //数据位为8位 options.c_lflag &= ~(ICANON | ECHO | ECHOE | ISIG); tcsetattr(device_fd,TCSANOW,&options); } int at_send_command(int device_fd, char *cmd) { int ret; ret = write(device_fd, cmd, strlen(cmd)); return ret; } void request_setup_datacall(int device_fd) { const char *apn = "cmnet"; char *cmd = NULL; int err; ALOGD("requesting data connection to APN '%s'", apn); if(pppd_started) { ALOGD("Stop existing PPPd before activating PDP"); property_set("ctl.stop", PPPD_SERVICE_NAME);//设置pppd_gprs属性为停止 pppd_started = 0; } err = at_send_command(device_fd, "at$qcpdplt=0"); asprintf(&cmd, "AT+CGDCONT=1,\"IP\",\"%s\",,0,0", apn);//设置PDP上下文 err = at_send_command(device_fd, cmd); free(cmd); if (err < 0 ) { ALOGD("AT Send Command error!"); } err = property_set(PPPD_EXIT_CODE, "");//设置net.gprs.ppp-exit为空 if (err < 0) { ALOGW("Set PPPD_EXIT_CODE failed!"); goto ppp_error; } err = property_set(PPP_NET_LOCAL_IP, "");//设置net.ppp0.local-ip为空 if (err < 0) { ALOGW("Set PPPD_NET_LOCAL_IP failed!"); goto ppp_error; } err = property_set("ctl.start", PPPD_SERVICE_NAME);//设置pppd_gprs属性为启动 pppd_started = 1; if (err < 0) { ALOGW("Can not start PPPd"); goto ppp_error; } ALOGD("PPPd started"); return; ppp_error: at_send_command(device_fd, "AT+CGACT=0,1");//PDP上下文去激活 if(pppd_started) { property_set("ctl.stop", PPPD_SERVICE_NAME); pppd_started = 0; } } void *ip_detection(void *arg) { int fd; int err; int device_fd = (int)arg; char buffer[20]; char exit_code[PROPERTY_VALUE_MAX]; static char local_ip[PROPERTY_VALUE_MAX]; static int pppd_started = 0; sleep(2); while(1){ property_get(PPPD_EXIT_CODE, exit_code, "");//获取pppd的退出状态 if(strcmp(exit_code, "") != 0) {//检测pppd是否异常退出 ALOGW("PPPd exit with code %s", exit_code); request_setup_datacall(device_fd);//继续执行拨号 goto done; } fd = open(PPP_OPERSTATE_PATH, O_RDONLY);//读取/sys/class/net/ppp0/operstate来监控数据网络数据的状态 if (fd >= 0) { buffer[0] = 0; read(fd, buffer, sizeof(buffer)); close(fd); ALOGW("buffer = %s", buffer); if(!strncmp(buffer, "up", strlen("up")) || !strncmp(buffer, "unknown", strlen("unknown"))) { memset(local_ip,'\0',sizeof(local_ip)); err = property_get(PPP_NET_LOCAL_IP, local_ip, "");//获取IP if (err < 0) { ALOGW("Get PPPD_NET_LOCAL_IP failed!"); } if(!strcmp(local_ip, "")) { ALOGW("PPP link is up but no local IP is assigned. Will retry times after %d seconds",PPP_SYSFS_RETRY); property_set("ctl.stop", PPPD_SERVICE_NAME);//如果没有IP停止pppd } else { ALOGD("PPP link is up with local IP address %s", local_ip); } } else { ALOGW("PPP link status in %s is %s. Will retry times after %d seconds", \ PPP_OPERSTATE_PATH, buffer, PPP_SYSFS_RETRY); property_set("ctl.stop", PPPD_SERVICE_NAME);//如果数据网络数据的状态不对停止pppd } } else { ALOGW("Can not detect PPP state in %s. Will retry times after %d seconds", \ PPP_OPERSTATE_PATH ,PPP_SYSFS_RETRY); request_setup_datacall(device_fd);//继续执行拨号 } done: sleep(PPP_SYSFS_RETRY); } return NULL; }
3、ril_fun.h
#ifndef _RIL_FUN_H_ #define _RIL_FUN_H_ #include <unistd.h> #include <utils/Log.h> //ALOG*() #include <cutils/properties.h> //property_set() #define PPPD_SERVICE_NAME "pppd_gprs" /************************************************************* * 功能: 打开串口设备文件 * 参数: device_path: 串口设备文件名 * 返回值: 串口设备文件描述符 **************************************************************/ int device_open(char *device_path); /************************************************************* * 功能: 初始化设备节点 * 参数: device_fd: 串口设备文件描述符 * 返回值: 无 **************************************************************/ void device_init(int device_fd); /************************************************************* * 功能: 发送AT指令函数 * 参数: device_fd: 串口设备文件描述符 * cmd:AT命令 * 返回值: ret:状态 **************************************************************/ int at_send_command(int device_fd, char *cmd); /************************************************************* * 功能: 建立拨号函数 * 参数: device_fd: 串口设备文件描述符 * 返回值: 无 **************************************************************/ void request_setup_datacall(int device_fd); /************************************************************* * 功能: 创建查询IP线程 * 参数: arg: void类型指针 * 返回值: NULL **************************************************************/ void *ip_detection(void *arg); #endif
4、Android.mk
LOCAL_PATH:= $(call my-dir) include $(CLEAR_VARS) LOCAL_SRC_FILES:= \ rild.c \ ril_fun.c LOCAL_SHARED_LIBRARIES := \ libcutils \ libdl LOCAL_LDLIBS += -lpthread LOCAL_MODULE:= rild LOCAL_MODULE_TAGS := optional include $(BUILD_EXECUTABLE)
上述文件添加好后,进行编译,在编译前如果之前编译过要进行清理,执行make clean
二、把下面的脚本放到板子的/etc/ppp下
1、init.gprs-pppd
#!/system/bin/sh # An unforunate wrapper script # so that the exit code of pppd may be retrieved PPPD_PID= /system/bin/setprop "net.gprs.ppp-exit" "" #设置net.gprs.ppp-exit为空 /system/bin/log -t pppd "Starting pppd" /system/bin/pppd connect 'chat -v -s -r "/var/log/chat.log" -f "/etc/ppp/3gdata_call.conf"' disconnect \ 'chat -r "/var/log/chat.log" -t 30 -e -v "" +++ATH "NO CARRIER"' /dev/ttyUSB3 115200 mru 1280 mtu 1280 \ nodetach debug dump defaultroute usepeerdns novj novjccomp crtscts user card password card noipdefault ipcp-accept-local \ ipcp-accept-remote linkname ppp0 PPPD_EXIT=$? #获得执行命令后的返回值 PPPD_PID=$! #最后运行的后台进程的PID /system/bin/log -t pppd "pppd exited with $PPPD_EXIT" /system/bin/setprop "net.gprs.ppp-exit" "$PPPD_EXIT" #把返回值设置给net.gprs.ppp-exit
注:脚本中的/dev/ttyUSB3为模块USB串口的Modem口。
2、3gdata_call.conf
ABORT "NO CARRIER" ABORT "NO DIALTONE" ABORT "ERROR" ABORT "NO ANSWER" ABORT "BUSY" TIMEOUT 120 "" at OK atd*99***1# CONNECT
三、修改ini.rc脚本
打开 .../device/fsl/imx6/etc/init.rc按照如下红色框进行修改
添加修改新加入文件权限的语句。
注:/dev/ttyUSB2是模块USB串口的AT口。
到此,就可以进行打包 make snod ,烧写镜像进行测试了。
可以用命令:logcat -b radio 查看rild 输出的信息进行调试。如果一切正常会打印出IP(或用命令 necfg 查看IP),有IP后用命令 ping 202.108.22.5 (百度IP)看下网络是否能ping通。如果能ping通证明自动拨号已经成功。此时用命令 ps查看rild和pppd进程号,用命令kill -9 <进程号> 杀死随便一个进程,在5s之后看看是不是该进程又运行了。