第一部分：从java端发送at命令的处理流程。

拨出电话流程：

1、Contacts的AndroidManifest.xml 中android:process="android.process.acore" 说明此应用程序运行在acore进程中。

DialtactsActivity的intent-filter的action属性设置为main，catelog属性设置为launcher，所以此 activity能出现在主菜单中，并且是点击此应用程序的第一个界面。dialtactsactivity包含四个tab，分别由 TwelveKeyDialer、RecentCallsListActivity，两个activity-alias DialtactsContactsEntryActivity和DialtactsFavoritesEntryActivity分别表示联系人和收藏 tab，但是正真的联系人列表和收藏是由ContactsListActivity负责。

2、进入TwelveKeyDialer 中OnClick方法，按住的按钮id为：R.id.dialButton，执行placecall()方法：

Intent intent = new Intent(Intent.ACTION_CALL_PRIVILEGED,Uri.fromParts("tel", number, null));

intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

startActivity(intent);

3、intert.ACTION_CALL_PRIVILEGED实际字符串为 android.intent.action.CALL_PRIVILEGED，通过查找知道了packegs/phone下面的 AndroidManifest.xml中PrivilegedOutgoingCallBroadcaster activity-alias设置了intent-filter，所以需要找到其targetactivity为 OutgoingCallBroadcaster。所以进入OutgoingCallBroadcaster的onCreate（）中：

String action = intent.getAction();
  String number = PhoneNumberUtils.getNumberFromIntent(intent, this);
  if (number != null) {
         number = PhoneNumberUtils.convertKeypadLettersToDigits(number);
         number = PhoneNumberUtils.stripSeparators(number);
   }
  final boolean emergencyNumber =
                (number != null) && PhoneNumberUtils.isEmergencyNumber(number);

获取过来的Action以及Number，并对Action以及Number类型进行判断。

//如果为callNow = true；则启动InCall界面：

intent.setClass(this, InCallScreen.class);

startActivity(intent);

并发送广播给OutgoingCallReceiver：

Intent broadcastIntent = new Intent(Intent.ACTION_NEW_OUTGOING_CALL);

if (number != null) broadcastIntent.putExtra(Intent.EXTRA_PHONE_NUMBER, number);

broadcastIntent.putExtra(EXTRA_ALREADY_CALLED, callNow);

broadcastIntent.putExtra(EXTRA_ORIGINAL_URI, intent.getData().toString() );

sendOrderedBroadcast(broadcastIntent, PERMISSION,
                new OutgoingCallReceiver(), null, Activity.RESULT_OK, number, null);

4、Intent.ACTION_NEW_OUTGOING_CALL实际字符串 android.intent.action.NEW_OUTGOING_CALL，通过查找知道了packegs/phone下面的 androidmanifest.xml中OutgoingCallReceiver Receiver接收此intent消息。找到OutgoingCallBroadcaster类中的内部类OutgoingCallReceiver， 执行onReceive()函数：

执行doReceive(context, intent);方法：

获取传给来的号码，根据PhoneApp的实例获取PhoneType等。最后启动InCall界面：

Intent newIntent = new Intent(Intent.ACTION_CALL, uri);

newIntent.putExtra(Intent.EXTRA_PHONE_NUMBER, number);

newIntent.setClass(context, InCallScreen.class);

newIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);

5、请求拨号的java部分流程

6、请求拨号的c/c++部分流程

6.1、初始化事件循环，启动串口监听，注册socket监听。

rild.c->main()

(1)、RIL_startEventLoop

//建立事件循环线程

ret = pthread_create(&s_tid_dispatch, &attr, eventLoop, NULL);

//注册进程唤醒事件回调

ril_event_set (&s_wakeupfd_event, s_fdWakeupRead, true,

processWakeupCallback, NULL);

rilEventAddWakeup (&s_wakeupfd_event);

//建立事件循环

ril_event_loop

for (;;) {

...

n = select(nfds, &rfds, NULL, NULL, ptv);

// Check for timeouts

processTimeouts();

// Check for read-ready

processReadReadies(&rfds, n);

// Fire away

firePending();

}

(2)、funcs = rilInit(&s_rilEnv, argc, rilArgv);//实际是通过动态加载动态库的方式执行reference-ril.c中的RIL_Init

//单独启动一个线程读取串口数据

ret = pthread_create(&s_tid_mainloop, &attr, mainLoop, NULL);

fd = open (s_device_path, O_RDWR);

ret = at_open(fd, onUnsolicited);

ret = pthread_create(&s_tid_reader, &attr, readerLoop, &attr);

RIL_requestTimedCallback(initializeCallback, NULL, &TIMEVAL_0);

在initializeCallback中执行的程序：

setRadioState (RADIO_STATE_OFF);

at_handshake();

/* note: we don't check errors here. Everything important will

be handled in onATTimeout and onATReaderClosed */

/* atchannel is tolerant of echo but it must */

/* have verbose result codes */

at_send_command("ATE0Q0V1", NULL);

/* No auto-answer */

at_send_command("ATS0=0", NULL);

...

//注册rild socket端口事件监听到事件循环中

(3)、RIL_register(funcs);

s_fdListen = android_get_control_socket(SOCKET_NAME_RIL);

ret = listen(s_fdListen, 4);

ril_event_set (&s_listen_event, s_fdListen, false,

listenCallback, NULL);//将此端口加入事件select队列

rilEventAddWakeup (&s_listen_event);

如果rild socket端口有数据来了将执行listencallback函数

listencallback

//为此客户端连接创建新的监听句柄，s_fdListen继续监听其他客户端的连接。

s_fdCommand = accept(s_fdListen, (sockaddr *) &peeraddr, &socklen);

ril_event_set (&s_commands_event, s_fdCommand, 1,

processCommandsCallback, p_rs);//将此端口加入事件select队列

rilEventAddWakeup (&s_commands_event);

6.2、socket监听，收到dial的socket请求

processCommandsCallback

//读数据到p_record中

ret = record_stream_get_next(p_rs, &p_record, &recordlen);

processCommandBuffer(p_record, recordlen);

p.setData((uint8_t *) buffer, buflen);

// status checked at end

status = p.readInt32(&request);

status = p.readInt32 (&token);//请求队列中的序号

pRI = (RequestInfo *)calloc(1, sizeof(RequestInfo));

pRI->token = token;

/*

包含#include "ril_commands.h"语句，结构体如下：

typedef struct {

int requestNumber;

void (*dispatchFunction) (Parcel &p, struct RequestInfo *pRI);

int(*responseFunction) (Parcel &p, void *response, size_t responselen);

} CommandInfo;

*/

pRI->pCI = &(s_commands[request]);

pRI->p_next = s_pendingRequests;

s_pendingRequests = pRI;

pRI->pCI->dispatchFunction(p, pRI);

//假设是接收了dial指令,pRI->PCI->dispatchFunction(p,pRI)，调用dispatchDial (p,pRI)

dispatchDial (p,pRI)

s_callbacks.onRequest(pRI->pCI->requestNumber, &dial, sizeof(dial), pRI);

in reference-ril.c onRequest()

...

switch (request) {

case RIL_REQUEST_DIAL:

requestDial(data, datalen, t);

asprintf(&cmd, "ATD%s%s;", p_dial->address, clir);

ret = at_send_command(cmd, NULL);

err = at_send_command_full (command, NO_RESULT, NULL, NULL, 0, pp_outResponse);

err = at_send_command_full_nolock(command, type, responsePrefix, smspdu,timeoutMsec,   sponse);

err = writeline (command);

//此处等待，直到收到成功应答或失败的应答,如：ok,connect,error cme等

err = pthread_cond_wait(&s_commandcond, &s_commandmutex);

waiting....

waiting....

/* success or failure is ignored by the upper layer here.

it will call GET_CURRENT_CALLS and determine success that way */

RIL_onRequestComplete(t, RIL_E_SUCCESS, NULL, 0);

p.writeInt32 (RESPONSE_SOLICITED);

p.writeInt32 (pRI->token);

errorOffset = p.dataPosition();

p.writeInt32 (e);

if (e == RIL_E_SUCCESS) {

/* process response on success */

ret = pRI->pCI->responseFunction(p, response, responselen);

if (ret != 0) {

p.setDataPosition(errorOffset);

p.writeInt32 (ret);

}

}

sendResponse(p);

sendResponseRaw(p.data(), p.dataSize());

blockingWrite(fd, (void *)&header, sizeof(header));

blockingWrite(fd, data, dataSize);

6.4、串口监听收到atd命令的应答"OK"或"no carrier"等

readerLoop()

line = readline();

processLine(line);

handleFinalResponse(line);

pthread_cond_signal(&s_commandcond);//至此，前面的等待结束，接着执行RIL_onRequestComplete函数

6.5、java层收到应答后的处理,以dial为例子.

ril.java->RILReceiver.run()

for(;;)

{

...

length = readRilMessage(is, buffer);

p = Parcel.obtain();

p.unmarshall(buffer, 0, length);

p.setDataPosition(0);

processResponse(p);

type = p.readInt();

if (type == RESPONSE_SOLICITED) {

processSolicited (p);

serial = p.readInt();

rr = findAndRemoveRequestFromList(serial);

rr.mResult.sendToTarget();

......

}

CallTracker.java->handleMessage (Message msg)

switch (msg.what) {

case EVENT_OPERATION_COMPLETE:

ar = (AsyncResult)msg.obj;

operationComplete();

cm.getCurrentCalls(lastRelevantPoll);