前言
记录修改linphone-sdk-android过程，计划分为上、中、下三篇
本文是上篇，本篇仅记录下书问题2的初步排查过程，尽量描述排查问题过程中的思路与方向
余下两篇记录问题1、2的修复过程
背景
项目中使用的linphone-sdk-android版本为4.5.x，使用过程中发现以下两个问题：
- 打开音频编解码G722、G729时，发起呼叫的INVITE SDP中，没有G722、G729的RTP MAP，当时以为是linphone的bug，后面看源码及查资料发现可能不是bug，这里先按下不表
- 使用sdk提供的JavaLogger输出日志时，伪代码：
mFactory.getLoggingService().addListener(mAndroidLoggingService);，偶现JNI崩溃问题
--------- beginning of crash
2022-04-11 14:16:22.350 1142-1430/? A/libc: Fatal signal 6 (SIGABRT), code -6 in tid 1430 (RealLinphonePro)
2022-04-11 14:16:22.441 3756-3756/? A/DEBUG: *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** ***
2022-04-11 14:16:22.442 3756-3756/? A/DEBUG: Build fingerprint: 'Android/rk3288/rk3288:7.1.2/NHG47K/builde03162201:userdebug/test-keys'
2022-04-11 14:16:22.444 3756-3756/? A/DEBUG: Revision: '0'
2022-04-11 14:16:22.446 3756-3756/? A/DEBUG: ABI: 'arm'
2022-04-11 14:16:22.447 3756-3756/? A/DEBUG: pid: 1142, tid: 1430, name: RealLinphonePro >>> com.guodong.android.linphone <<<
2022-04-11 14:16:22.448 3756-3756/? A/DEBUG: signal 6 (SIGABRT), code -6 (SI_TKILL), fault addr --------
2022-04-11 14:16:22.454 3756-3756/? A/DEBUG: Abort message: 'art/runtime/indirect_reference_table.cc:80] JNI ERROR (app bug): accessed deleted WeakGlobal 0x21ab'
2022-04-11 14:16:22.456 3756-3756/? A/DEBUG: r0 00000000 r1 00000596 r2 00000006 r3 00000008
2022-04-11 14:16:22.457 3756-3756/? A/DEBUG: r4 89aff978 r5 00000006 r6 89aff920 r7 0000010c
2022-04-11 14:16:22.459 3756-3756/? A/DEBUG: r8 00000043 r9 aaa7eef0 sl 0000000a fp 89d04400
2022-04-11 14:16:22.461 3756-3756/? A/DEBUG: ip 0000000b sp 89afef88 lr ab175857 pc ab1780c0 cpsr 600b0010
2022-04-11 14:16:22.509 3756-3756/? A/DEBUG: backtrace:
2022-04-11 14:16:22.511 3756-3756/? A/DEBUG: #00 pc 0004a0c0 /system/lib/libc.so (tgkill+12)
2022-04-11 14:16:22.512 3756-3756/? A/DEBUG: #01 pc 00047853 /system/lib/libc.so (pthread_kill+34)
2022-04-11 14:16:22.514 3756-3756/? A/DEBUG: #02 pc 0001d8b5 /system/lib/libc.so (raise+10)
2022-04-11 14:16:22.515 3756-3756/? A/DEBUG: #03 pc 00019401 /system/lib/libc.so (__libc_android_abort+34)
2022-04-11 14:16:22.517 3756-3756/? A/DEBUG: #04 pc 00017048 /system/lib/libc.so (abort+4)
2022-04-11 14:16:22.518 3756-3756/? A/DEBUG: #05 pc 0031d8cd /system/lib/libart.so (_ZN3art7Runtime5AbortEPKc+328)
2022-04-11 14:16:22.520 3756-3756/? A/DEBUG: #06 pc 000b5503 /system/lib/libart.so (_ZN3art10LogMessageD2Ev+1134)
2022-04-11 14:16:22.521 3756-3756/? A/DEBUG: #07 pc 001bd0ff /system/lib/libart.so (_ZN3art22IndirectReferenceTable17AbortIfNoCheckJNIERKNSt3__112basic_stringIcNS1_11char_traitsIcEENS1_9allocatorIcEEEE+134)
2022-04-11 14:16:22.523 3756-3756/? A/DEBUG: #08 pc 0023ecaf /system/lib/libart.so (_ZNK3art22IndirectReferenceTable10GetCheckedEPv+250)
2022-04-11 14:16:22.525 3756-3756/? A/DEBUG: #09 pc 0023c05b /system/lib/libart.so (_ZN3art9JavaVMExt16DecodeWeakGlobalEPNS_6ThreadEPv+30)
2022-04-11 14:16:22.526 3756-3756/? A/DEBUG: #10 pc 00337679 /system/lib/libart.so (_ZNK3art6Thread13DecodeJObjectEP8_jobject+164)
2022-04-11 14:16:22.528 3756-3756/? A/DEBUG: #11 pc 00265843 /system/lib/libart.so (_ZN3art3JNI11NewLocalRefEP7_JNIEnvP8_jobject+406)
2022-04-11 14:16:22.530 3756-3756/? A/DEBUG: #12 pc 0060eff9 /data/app/com.guodong.android.linphone-1/lib/arm/liblinphone.so (getLoggingService+88)
2022-04-11 14:16:22.531 3756-3756/? A/DEBUG: #13 pc 0061a977 /data/app/com.guodong.android.linphone-1/lib/arm/liblinphone.so
2022-04-11 14:16:22.533 3756-3756/? A/DEBUG: #14 pc 005ef911 /data/app/com.guodong.android.linphone-1/lib/arm/liblinphone.so
2022-04-11 14:16:22.535 3756-3756/? A/DEBUG: #15 pc 00025437 /data/app/com.guodong.android.linphone-1/lib/arm/libbctoolbox.so (bctbx_logv+182)
2022-04-11 14:16:22.536 3756-3756/? A/DEBUG: #16 pc 006f5061 /data/app/com.guodong.android.linphone-1/lib/arm/liblinphone.so
2022-04-11 14:16:22.538 3756-3756/? A/DEBUG: #17 pc 006f51d9 /data/app/com.guodong.android.linphone-1/lib/arm/liblinphone.so (wake_lock_acquire+152)
2022-04-11 14:16:22.539 3756-3756/? A/DEBUG: #18 pc 006601c5 /data/app/com.guodong.android.linphone-1/lib/arm/liblinphone.so
2022-04-11 14:16:22.541 3756-3756/? A/DEBUG: #19 pc 00660b27 /data/app/com.guodong.android.linphone-1/lib/arm/liblinphone.so (belle_sip_client_transaction_init+138)
2022-04-11 14:16:22.542 3756-3756/? A/DEBUG: #20 pc 006fb1d3 /data/app/com.guodong.android.linphone-1/lib/arm/liblinphone.so (belle_sip_nict_new+30)
2022-04-11 14:16:22.544 3756-3756/? A/DEBUG: #21 pc 0065c3a7 /data/app/com.guodong.android.linphone-1/lib/arm/liblinphone.so (belle_sip_provider_create_client_transaction+46)
2022-04-11 14:16:22.546 3756-3756/? A/DEBUG: #22 pc 0065dec3 /data/app/com.guodong.android.linphone-1/lib/arm/liblinphone.so
2022-04-11 14:16:22.547 3756-3756/? A/DEBUG: #23 pc 0065daf7 /data/app/com.guodong.android.linphone-1/lib/arm/liblinphone.so (belle_sip_refresher_refresh+28)
2022-04-11 14:16:22.549 3756-3756/? A/DEBUG: #24 pc 005fac23 /data/app/com.guodong.android.linphone-1/lib/arm/liblinphone.so (linphone_proxy_config_refresh_register+34)
2022-04-11 14:16:22.550 3756-3756/? A/DEBUG: #25 pc 005e9fc5 /data/app/com.guodong.android.linphone-1/lib/arm/liblinphone.so (linphone_core_refresh_registers+40)
2022-04-11 14:16:22.552 3756-3756/? A/DEBUG: #26 pc 019fc3bf /data/app/com.guodong.android.linphone-1/oat/arm/base.odex (offset 0x18de000)
2022-04-11 14:16:23.096 227-255/? I/AudioFlinger: BUFFER TIMEOUT: remove(4099) from active list on thread 0xabd03e00
分析
问题2
通过崩溃日志第27行2022-04-11 14:16:22.530 3756-3756/? A/DEBUG: #12 pc 0060eff9 /data/app/com.guodong.android.linphone-1/lib/arm/liblinphone.so (getLoggingService+88)可以判断崩溃是在getLoggingService()这个方法里
如此需要先找到getLoggingService()方法的源码，先在Source Insight中搜索getLoggingService()，搜索一圈发现没有，猜想此方法应该是编译后自动生成的
在Ubuntu编译环境里找找，通过find命令查找包含getLoggingService文本的文件
$ cd linphone-sdk/build/
$ find . -type f | xargs grep "getLoggingService"
./WORK/android-armv7/Build/linphone/wrappers/java/src/linphone_jni.cc:JNIEXPORT jobject JNICALL getLoggingService(JNIEnv *env, LinphoneLoggingService *cptr, bool_t takeref) {
./WORK/android-armv7/Build/linphone/wrappers/java/src/linphone_jni.cc: jobject j_logService = getLoggingService(env, (LinphoneLoggingService *)logService, TRUE);
./WORK/android-armv7/Build/linphone/wrappers/java/src/linphone_jni.cc: jobject jni_result = (jobject)getLoggingService(env, (LinphoneLoggingService *)linphone_logging_service_get(), TRUE);
找到了bingo~
打开linphone_jni.cc，getLoggingService()方法体如下：
JNIEXPORT jobject JNICALL getLoggingService(JNIEnv *env, LinphoneLoggingService *cptr, bool_t takeref) {
jobject jobj = nullptr;
if (cptr != nullptr) {
void *up = belle_sip_object_data_get((belle_sip_object_t *)cptr, belle_sip_java_user_data_key);
LinphoneJavaBindings *ljb = (LinphoneJavaBindings *)linphone_factory_get_user_data(linphone_factory_get());
if (!ljb) {
ljb = new LinphoneJavaBindings(env);
linphone_factory_set_user_data(linphone_factory_get(), ljb);
}
jclass linphone_logging_service_class = ljb->linphone_logging_service_class;
jmethodID linphone_logging_service_constructor = ljb->linphone_logging_service_class_constructor;
if (up == nullptr) {
jobj = env->NewObject(linphone_logging_service_class, linphone_logging_service_constructor, (jlong)cptr);
belle_sip_object_data_set((belle_sip_object_t *)cptr, belle_sip_java_user_data_key, (void*)env->NewWeakGlobalRef(jobj), nullptr);
if (takeref)
linphone_logging_service_ref(cptr);
} else {
jobj = env->NewLocalRef((jobject)up);
if (jobj == nullptr) {
// Delete weak ref ?
env->DeleteWeakGlobalRef((jobject)up);
// takes implicit local ref
jobj = env->NewObject(linphone_logging_service_class, linphone_logging_service_constructor, (jlong)cptr);
belle_sip_object_data_set((belle_sip_object_t *)cptr, belle_sip_java_user_data_key, (void*)env->NewWeakGlobalRef(jobj), nullptr);
if (takeref)
linphone_logging_service_ref(cptr);
}
}
}
return jobj;
}
嗯，看起来没啥问题，也有判空处理，一时间摸不着头绪，先在getLoggingService()方法中加点日志输出看看吧
前面说linphone_jni.cc是自动生成的，现在需要找到自动生成linphone_jni.cc的代码，根据崩溃日志可以发现getLoggingService()在linphone.so中，而源码中有liblinphone这个目录，先在这个目录下找找吧，通过find命令查找文件名中包含jni的文件
$ cd linphone-sdk/liblinphone/
$ find . -name *jni*
./coreapi/linphonecore_jni.cc
./tools/lpc2xml_jni.cc
./tools/xml2lpc_jni.cc
./tools/my_jni.h
./wrappers/java/jni.mustache
查找出来多个文件，既然linphone_jni.cc是自动生成的，所以可以确定.cc、.h后缀的几个文件肯定不是，排除后只剩下这个jni.mustache文件，打开文件vim ./wrappers/java/jni.mustache注释第一行就是linphone_jni.cc，太棒了，找到自动生成的代码了
通过一些查看，并与linphone_jni.cc中的实现对比，锁定了以下代码即为自动生成的模板代码：
290 {{#objects}}
291 JNIEXPORT jobject JNICALL get{{className}}(JNIEnv *env, {{classCName}} *cptr, bool_t takeref) {
292 jobject jobj = nullptr;
293
294 if (cptr != nullptr) {
295 void *up = belle_sip_object_data_get((belle_sip_object_t *)cptr, belle_sip_java_user_data_key);
296 LinphoneJavaBindings *ljb = (LinphoneJavaBindings *)linphone_factory_get_user_data(linphone_factory_get());
297 if (!ljb) {
298 ljb = new LinphoneJavaBindings(env);
299 linphone_factory_set_user_data(linphone_factory_get(), ljb);
300 }
301
302 jclass {{cPrefix}}_class = ljb->{{cPrefix}}_class;
303 jmethodID {{cPrefix}}_constructor = ljb->{{cPrefix}}_class_constructor;
304
305 if (up == nullptr) {
306 jobj = env->NewObject({{cPrefix}}_class, {{cPrefix}}_constructor, (jlong)cptr);
307 belle_sip_object_data_set((belle_sip_object_t *)cptr, belle_sip_java_user_data_key, (void*)env->NewWeakGlobalRef(jobj), nullptr);
308 if (takeref)
309 {{#refCountable}}{{cPrefix}}_ref(cptr);{{/refCountable}}
310 } else {
311 jobj = env->NewLocalRef((jobject)up);
312 if (jobj == nullptr) {
313 // Delete weak ref ?
314 env->DeleteWeakGlobalRef((jobject)up);
315 // takes implicit local ref
316 jobj = env->NewObject({{cPrefix}}_class, {{cPrefix}}_constructor, (jlong)cptr);
317 belle_sip_object_data_set((belle_sip_object_t *)cptr, belle_sip_java_user_data_key, (void*)env->NewWeakGlobalRef(jobj), nullptr);
318 if (takeref)
319 {{#refCountable}}{{cPrefix}}_ref(cptr);{{/refCountable}}
320 }
321 }
322 }
323 return jobj;
324 }
这里linphone-sdk使用了mustache，还记得在上篇编译Linphone-SDK-Android中有安装pip3 install pystache，pystache是mustache的Python实现，mustache的语法比较简单，在github上看一眼文档，再跟着源码比着葫芦画瓢，应该就差不多了
好的，学习完mustache的语法，了解到高级用法可以传一个配置文件进行渲染，正好与jni.mustache同级目录中有个genwrapper.py文件，打开此文件，里面定义了很多类，其中有个Jni的类，里面有些字段与jni.mustache中的标签正好对应，就是它了
class Jni:
def add_object(self, javaClass):
if javaClass.className == 'Factory':
return
obj = {
'jniPrefix': self.jni_package,
'jniPath': self.jni_path,
'cPrefix': javaClass.cPrefix,
'className': javaClass.className,
'classCName': javaClass.cName,
'classImplName': javaClass.classImplName,
'refCountable': javaClass.refCountable,
'notRefCountable': not javaClass.refCountable,
}
self.objects.append(obj)
happy~万事具备，现在可以修改源码，添加一些日志输出了
因为在jni.mustache中模板方法get{{className}}是可以生成多个以get开头的方法，现在需要判断{{className}}是不是等于LoggingService，而在mustache中没有发现比较字符串是否相同的语法，所以在genwrapper.py的Jni类中新增一个isLoggingService字段表示是否是getLoggingService()方法
class Jni:
def add_object(self, javaClass):
if javaClass.className == 'Factory':
return
obj = {
'jniPrefix': self.jni_package,
'jniPath': self.jni_path,
'cPrefix': javaClass.cPrefix,
'className': javaClass.className,
'classCName': javaClass.cName,
'classImplName': javaClass.classImplName,
'refCountable': javaClass.refCountable,
'notRefCountable': not javaClass.refCountable,
'isLoggingService': javaClass.className == 'LoggingService',
}
self.objects.append(obj)
然后修改jni.mustache文件，增加日志，输出up指针指向的地址，up指针转成jobject后与NULL、nullptr比较的结果，判断up是否已经被回收了
这里说一下代码的大概意思，up指针从belle_sip_object_data_get方法中通过belle_sip_java_user_data_key这个Key获取，可以简单理解为Java中的Map；如果up为空，则调用Java方法创建一个对象，将创建的Java对象通过NewWeakGlobalRef方法转换为全局弱引用，再通过belle_sip_object_data_set方法保存起来；如果up不为空，则强转为jobject，判断jobject是否为空，为空则删除全局弱引用，再创建保存
{{#objects}}
JNIEXPORT jobject JNICALL get{{className}}(JNIEnv *env, {{classCName}} *cptr, bool_t takeref) {
jobject jobj = nullptr;
if (cptr != nullptr) {
void *up = belle_sip_object_data_get((belle_sip_object_t *)cptr, belle_sip_java_user_data_key);
LinphoneJavaBindings *ljb = (LinphoneJavaBindings *)linphone_factory_get_user_data(linphone_factory_get());
if (!ljb) {
ljb = new LinphoneJavaBindings(env);
linphone_factory_set_user_data(linphone_factory_get(), ljb);
}
jclass {{cPrefix}}_class = ljb->{{cPrefix}}_class;
jmethodID {{cPrefix}}_constructor = ljb->{{cPrefix}}_class_constructor;
{{#isLoggingService}}
#ifdef __ANDROID__
__android_log_print(ANDROID_LOG_DEBUG, "guodongAndroid", "up = %p", up);
jobject temp_jobj1 = (jobject)up;
jboolean up_available1 = env->IsSameObject(temp_jobj1, NULL);
__android_log_print(ANDROID_LOG_DEBUG, "guodongAndroid", "up_available1 = %d", up_available1);
jobject temp_jobj2 = (jobject)up;
jboolean up_available2 = env->IsSameObject(temp_jobj2, nullptr);
__android_log_print(ANDROID_LOG_DEBUG, "guodongAndroid", "up_available2 = %d", up_available2);
#endif /* __ANDROID__ */
{{/isLoggingService}}
if (up == nullptr) {
jobj = env->NewObject({{cPrefix}}_class, {{cPrefix}}_constructor, (jlong)cptr);
belle_sip_object_data_set((belle_sip_object_t *)cptr, belle_sip_java_user_data_key, (void*)env->NewWeakGlobalRef(jobj), nullptr);
if (takeref)
{{#refCountable}}{{cPrefix}}_ref(cptr);{{/refCountable}}
} else {
jobj = env->NewLocalRef((jobject)up);
if (jobj == nullptr) {
// Delete weak ref ?
env->DeleteWeakGlobalRef((jobject)up);
// takes implicit local ref
jobj = env->NewObject({{cPrefix}}_class, {{cPrefix}}_constructor, (jlong)cptr);
belle_sip_object_data_set((belle_sip_object_t *)cptr, belle_sip_java_user_data_key, (void*)env->NewWeakGlobalRef(jobj), nullptr);
if (takeref)
{{#refCountable}}{{cPrefix}}_ref(cptr);{{/refCountable}}
}
}
}
return jobj;
}
好的，修改完源码保存后，就可以编译了
$ cd linphone-sdk/build/
$ cmake --build . --parallel 8
等待编译完成，拷贝出来编译好的aar，放到Android Studio中运行，查看Logcat输出
