Android L 5.0 上紧急电话EmergencyCall与普通电话在MO流程上的区别

转载请注明出处：http://blog.csdn.net/aaa111/article/details/47296721

拨打紧急号码的流程，以112为例。

参考了有SIM卡，无SIM卡，和有SIM卡但开启飞行模式的log，将分析结果简单整理如下。
首先紧急电话的拨打流程也是一个MO流程，至于相对于普通号码在流程细节上有几处区别，那么我们以普通MO流程为参考，着重讲一下不同之处。 下面是一个MO的流程图：



在MO流程中call action有三种，我们先看一下他们分别用在什么时候，在NewOutgoingCallIntentBroadcaster.java中processIntent()方法前的注释中可以看到：

/**

* Processes the supplied intent and starts the outgoing call broadcast process relevant to the

* intent.

*

* This method will handle three kinds of actions:

*

* - CALL (intent launched by all third party dialers)

* - CALL_PRIVILEGED (intent launched by system apps e.g. system Dialer, voice Dialer)

* - CALL_EMERGENCY (intent launched by lock screen emergency dialer)

*

* @return {@link CallActivity#OUTGOING_CALL_SUCCEEDED} if the call succeeded, and an

*         appropriate {@link DisconnectCause} if the call did not, describing why it failed.

*/

CALL为第三方的拨号程序，CALL_PRIVILEGED是系统拨号程序，CALL_EMERGENCY是锁屏界面的emergency 拨号程序。

但是在系统拨号程序中拨入号码，系统是如何是辨认emergency number的呢？
往方法里面可以看到，代码中通过isPotentialEmergencyNumber()判断这个是不是Emergency Number（注：是否是Emergency Number 是跟SIM卡以及国家有关的，好像是在PhoneNumberUtil中），如果是的话就去重写Intent 的Action值，
8 android/packages/services/Telecomm/src/com/android/server/telecom/NewOutgoingCallIntentBroadcaster.java   processIntent()

final boolean isPotentialEmergencyNumber = isPotentialEmergencyNumber(number);

Log.v(this, "isPotentialEmergencyNumber = %s", isPotentialEmergencyNumber);

rewriteCallIntentAction(intent, isPotentialEmergencyNumber);//紧急号码的话 重写action值为android.intent.action.CALL_EMERGENCY了

在isPotentialEmergencyNumber()方法前的注释中，我们可以看到，“in order to enforce the restriction that only the CALL_PRIVILEGED and CALL_EMERGENCY intents are allowed
to make emergency  calls.”
那我们是否得出结论第三方的拨号程序是不允许拨打紧急电话的？（five minutes later）试了某第三方拨号程序，拨打112的时候会跳转到系统dialer，不会直接拨出电话。
在rewriteCallIntentAction()方法中“ updating
action from CALL_PRIVILEGED to android.intent.action.CALL_EMERGENCY”

11 android/packages/services/Telecomm/src/com/android/server/telecom/CallsManager.java

void placeOutgoingCall(Call call, Uri handle, GatewayInfo gatewayInfo, boolean speakerphoneOn,

int videoState) {

if (call == null) {

// don't do anything if the call no longer exists

Log.i(this, "Canceling unknown call.");

return;

}

final Uri uriHandle = (gatewayInfo == null) ? handle : gatewayInfo.getGatewayAddress();

if (gatewayInfo == null) {

Log.i(this, "Creating a new outgoing call with handle: %s", Log.piiHandle(uriHandle));

} else {

Log.i(this, "Creating a new outgoing call with gateway handle: %s, original handle: %s",

Log.pii(uriHandle), Log.pii(handle));

}

call.setHandle(uriHandle);

call.setGatewayInfo(gatewayInfo);

call.setStartWithSpeakerphoneOn(speakerphoneOn);

call.setVideoState(videoState);

boolean isEmergencyCall = TelephonyUtil.shouldProcessAsEmergency(mContext,

call.getHandle());

if (isEmergencyCall) {

// Emergency -- CreateConnectionProcessor will choose accounts automatically

call.setTargetPhoneAccount(null);

}

if (call.getTargetPhoneAccount() != null || isEmergencyCall) {

if (!isEmergencyCall) {

updateLchStatus(call.getTargetPhoneAccount().getId());

}

// If the account has been set, proceed to place the outgoing call.

// Otherwise the connection will be initiated when the account is set by the user.

call.startCreateConnection(mPhoneAccountRegistrar);

}

}

13 android/packages/services/Telecomm/src/com/android/server/telecom/CreateConnectionProcessor.java

void process() {

Log.v(this, "process");

mAttemptRecords = new ArrayList<>();

if (mCall.getTargetPhoneAccount() != null) {

mAttemptRecords.add(new CallAttemptRecord(

mCall.getTargetPhoneAccount(), mCall.getTargetPhoneAccount()));

}

adjustAttemptsForConnectionManager();

adjustAttemptsForEmergency();

mAttemptRecordIterator = mAttemptRecords.iterator();

attemptNextPhoneAccount();

}

14 如果是一般的号码那么执行adjustAttemptsForEmergency()并不会对流程有什么影响，如果是紧急号码的话那么我们进来看看它做了什么。

// If we are possibly attempting to call a local emergency number, ensure that the

// plain PSTN connection services are listed, and nothing else.

private void adjustAttemptsForEmergency()  {

if (TelephonyUtil.shouldProcessAsEmergency(mContext, mCall.getHandle())) {

Log.i(this, "Emergency number detected");

mAttemptRecords.clear();

List<PhoneAccount> allAccounts = mPhoneAccountRegistrar.getAllPhoneAccounts();//获得所有账户（SIM/SIP/IMS等）

if (allAccounts.isEmpty()) {//如果是空的话

// If the list of phone accounts is empty at this point, it means Telephony hasn't

// registered any phone accounts yet. Add a fallback emergency phone account so

// that emergency calls can still go through. We create a new ArrayLists here just

// in case the implementation of PhoneAccountRegistrar ever returns an unmodifiable

// list.

allAccounts = new ArrayList<PhoneAccount>();

allAccounts.add(TelephonyUtil.getDefaultEmergencyPhoneAccount());

//如果是空的话，那么我么赋予一个默认的紧急拨号账户

}

// First, add SIM phone accounts which can place emergency calls.

for (PhoneAccount phoneAccount : allAccounts) {

if (phoneAccount.hasCapabilities(PhoneAccount.CAPABILITY_PLACE_EMERGENCY_CALLS) &&

phoneAccount.hasCapabilities(PhoneAccount.CAPABILITY_SIM_SUBSCRIPTION)) {

Log.i(this, "Will try PSTN account %s for emergency",

    //PSTN?

phoneAccount.getAccountHandle());

mAttemptRecords.add(

new CallAttemptRecord(

phoneAccount.getAccountHandle(),

phoneAccount.getAccountHandle()));

}

}

// Next, add the connection manager account as a backup if it can place emergency calls.

PhoneAccountHandle callManagerHandle = mPhoneAccountRegistrar.getSimCallManager();

if (callManagerHandle != null) {

PhoneAccount callManager = mPhoneAccountRegistrar

.getPhoneAccount(callManagerHandle);

if (callManager.hasCapabilities(PhoneAccount.CAPABILITY_PLACE_EMERGENCY_CALLS)) {

CallAttemptRecord callAttemptRecord = new CallAttemptRecord(callManagerHandle,

mPhoneAccountRegistrar.

getDefaultOutgoingPhoneAccount(mCall.getHandle().getScheme())

);

if (!mAttemptRecords.contains(callAttemptRecord)) {

Log.i(this, "Will try Connection Manager account %s for emergency",

callManager);

    mAttemptRecords.add(callAttemptRecord);

}

}

}

}

}

allAccounts.add(TelephonyUtil.getDefaultEmergencyPhoneAccount());如果phone
Account是空的（没有SIM/SIP等），那么则返回一个专用的EmergencyPhoneAccount

/**

* @return fallback {@link PhoneAccount} to be used by Telecom for emergency calls in the

* rare case that Telephony has not registered any phone accounts yet. Details about this

* account are not expected to be displayed in the UI, so the description, etc are not

* populated.

*/

static PhoneAccount getDefaultEmergencyPhoneAccount() {

return PhoneAccount.builder(DEFAULT_EMERGENCY_PHONE_ACCOUNT_HANDLE, "E")

.setCapabilities(PhoneAccount.CAPABILITY_SIM_SUBSCRIPTION |

PhoneAccount.CAPABILITY_CALL_PROVIDER |

PhoneAccount.CAPABILITY_PLACE_EMERGENCY_CALLS).build();

}

这个CAPABILITY_SIM_SUBSCRIPTION比较奇特啊，a built-in PSTN SIM subscription，一个内置的SIM账户？

/**

* Flag indicating that this {@code PhoneAccount} represents a built-in PSTN SIM

* subscription.

* <p>

* Only the Android framework can register a {@code PhoneAccount} having this capability.

* <p>

* See {@link #getCapabilities}

*/

public static final int CAPABILITY_SIM_SUBSCRIPTION = 0x4;

下面是几种情况下拨打112 ，phoneAccount.getAccountHandle());打印出来的结果多是不同的，具体后面的 5 E 3 2 代表的什么意思我也不知道。了解的大神，求解释！求补充！

C:\Users\admin\Desktop\MO_Log\112 with simcard.txt (3 hits)

07-23 13:04:52.020    4146-4146/com.android.server.telecom I/Telecom﹕ Call: setTargetPhoneAccount

ComponentInfo{com.android.phone/com.android.services.telephony.TelephonyConnectionService}, 5

C:\Users\admin\Desktop\MO_Log\112 with no sim card.txt (4 hits)

07-23 13:06:06.409    4146-4146/com.android.server.telecom I/Telecom﹕ Call: setTargetPhoneAccount

ComponentInfo{com.android.phone/com.android.services.telephony.TelephonyConnectionService}, E （这个稍后会变成-1）

C:\Users\admin\Desktop\MO_Log\112 airplane mode.txt (3 hits)

07-23 13:08:57.877    4146-4146/com.android.server.telecom I/Telecom﹕ Call: setTargetPhoneAccount

ComponentInfo{com.android.phone/com.android.services.telephony.TelephonyConnectionService}, 3

C:\Users\admin\Desktop\MO_Log\MO.txt (1 hit)

04-04 14:25:02.677: I/Telecom(4147): Call: setTargetPhoneAccount  

ComponentInfo{com.android.phone/com.android.services.telephony.TelephonyConnectionService}, 2

15 之后继续 attemptNextPhoneAccount

如果已经开启飞行模式会关闭飞行模式先 log:

770: 07-23 13:08:58.351    4171-4171/com.android.phone D/Telephony﹕ EmergencyCallHelper: EmergencyCallHelper constructor.

770: 07-23 13:08:58.351    4171-4171/com.android.phone D/Telephony﹕ EmergencyCallHelper: EmergencyCallHelper constructor.

772: 07-23 13:08:58.352    4171-4171/com.android.phone D/Telephony﹕ EmergencyCallHelper: startTurnOnRadioSequence

788: 07-23 13:08:58.358    4171-4171/com.android.phone D/Telephony﹕ EmergencyCallHelper: startSequenceInternal()

790: 07-23 13:08:58.358    4171-4171/com.android.phone D/Telephony﹕ EmergencyCallHelper: cleanup()

794: 07-23 13:08:58.358    4171-4171/com.android.phone D/Telephony﹕ EmergencyCallHelper: powerOnRadio().

798: 07-23 13:08:58.359    4171-4171/com.android.phone D/Telephony﹕ EmergencyCallHelper: ==> Turning off airplane mode.

1720: 07-23 13:08:58.787    4171-4171/com.android.phone D/Telephony﹕ EmergencyCallHelper: onServiceStateChanged(), new state = 1 1 home null null null  Unknown Unknown CSS not supported -1 -1 RoamInd=-1 DefRoamInd=-1 EmergOnly=false.

1722: 07-23 13:08:58.787    4171-4171/com.android.phone D/Telephony﹕ EmergencyCallHelper: onServiceStateChanged: not ready to call yet, keep waiting.

1976: 07-23 13:08:59.019    4171-4171/com.android.phone D/Telephony﹕ EmergencyCallHelper: onServiceStateChanged(), new state = 0 1 home CHN-UNICOM UNICOM 46001  GSM Unknown CSS supported -1 -1 RoamInd=-1 DefRoamInd=-1 EmergOnly=false.

1978: 07-23 13:08:59.020    4171-4171/com.android.phone D/Telephony﹕ EmergencyCallHelper: onServiceStateChanged: ok to call!

2160: 07-23 13:08:59.092    4171-4171/com.android.phone D/Telephony﹕ EmergencyCallHelper: cleanup()

具体流程不详述，打开飞行模式的入口代码如下，并且打开radio之后，同样执行了placeOutgoingConnection方法。

25 android/packages/services/Telephony/src/com/android/services/telephony/TelephonyConnectionService.java

@Override

public Connection onCreateOutgoingConnection(

PhoneAccountHandle connectionManagerPhoneAccount,

final ConnectionRequest request) {

...

boolean useEmergencyCallHelper = false;

if (isEmergencyNumber) {

mRequest = request;

if (state == ServiceState.STATE_POWER_OFF) {//如果radio没有开

useEmergencyCallHelper = true;

}

}

...

if (useEmergencyCallHelper) {

if (mEmergencyCallHelper == null) {

mEmergencyCallHelper = new EmergencyCallHelper(this);

}

mEmergencyCallHelper.startTurnOnRadioSequence(phone,//打开radio，进而如果是开启了飞行模式的话则关闭飞行模式

new EmergencyCallHelper.Callback() {

@Override

public void onComplete(boolean isRadioReady) {

if (connection.getState() == Connection.STATE_DISCONNECTED) {

// If the connection has already been disconnected, do nothing.

} else if (isRadioReady) {

connection.setInitialized();

placeOutgoingConnection(connection,//打开radio后

PhoneFactory.getPhone(getPhoneIdForECall()), request);

} else {

Log.d(this, "onCreateOutgoingConnection, failed to turn on radio");

connection.setDisconnected(

DisconnectCauseUtil.toTelecomDisconnectCause(

android.telephony.DisconnectCause.POWER_OFF,

"Failed to turn on radio."));

connection.destroy();

}

}

});

}else {

placeOutgoingConnection(connection, phone, request);//如果radio本来就可用的话

}

}

而紧急号码和非紧急号码之间的区别，在 placeOutgoingConnection()中的第二个参数，Phone

（飞行模式的时候会打印两次？TelephonyConnectionService: Voice phoneId in service = 0 preferred phoneId =0）

26 android/packages/services/Telephony/src/com/android/services/telephony/TelephonyConnectionService.java

private void placeOutgoingConnection(

TelephonyConnection connection, Phone phone, ConnectionRequest request) {

String number = connection.getAddress().getSchemeSpecificPart();

PhoneAccountHandle pHandle = TelecomAccountRegistry.makePstnPhoneAccountHandle(phone);

// For ECall handling on MSIM, till the request reaches here(i.e PhoneApp)

// we dont know on which phone account ECall can be placed, once after deciding

// the phone account for ECall we should inform Telecomm so that

// the proper sub information will be displayed on InCallUI.

if (!Objects.equals(pHandle, request.getAccountHandle())) {

Log.i(this, "setPhoneAccountHandle, account = " + pHandle);

connection.setPhoneAccountHandle(pHandle);

}

Bundle bundle = request.getExtras();

boolean isAddParticipant = (bundle != null) && bundle

.getBoolean(TelephonyProperties.ADD_PARTICIPANT_KEY, false);

Log.d(this, "placeOutgoingConnection isAddParticipant = " + isAddParticipant);

com.android.internal.telephony.Connection originalConnection;

try {

if (isAddParticipant) {

phone.addParticipant(number);

    return;

} else {

originalConnection = phone.dial(number, request.getVideoState(), bundle);

    //拨号

}

} catch (CallStateException e) {

Log.e(this, e, "placeOutgoingConnection, phone.dial exception: " + e);

connection.setDisconnected(DisconnectCauseUtil.toTelecomDisconnectCause(

android.telephony.DisconnectCause.OUTGOING_FAILURE,

e.getMessage()));

return;

}

if (originalConnection == null) {

int telephonyDisconnectCause = android.telephony.DisconnectCause.OUTGOING_FAILURE;

// On GSM phones, null connection means that we dialed an MMI code

if (phone.getPhoneType() == PhoneConstants.PHONE_TYPE_GSM) {

Log.d(this, "dialed MMI code");

telephonyDisconnectCause = android.telephony.DisconnectCause.DIALED_MMI;

final Intent intent = new Intent(this, MMIDialogActivity.class);

intent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK |

Intent.FLAG_ACTIVITY_EXCLUDE_FROM_RECENTS);

startActivity(intent);

}

Log.d(this, "placeOutgoingConnection, phone.dial returned null");

connection.setDisconnected(DisconnectCauseUtil.toTelecomDisconnectCause(

telephonyDisconnectCause, "Connection is null"));

} else {

connection.setOriginalConnection(originalConnection);

}

}