Restore media.log service

Bug: 26306954
Change-Id: I00319f4869f46941e4c814a29b2f69a62e572743
diff --git a/media/audioserver/Android.mk b/media/audioserver/Android.mk
index 324ebbb..aa79bc1 100644
--- a/media/audioserver/Android.mk
+++ b/media/audioserver/Android.mk
@@ -9,11 +9,14 @@
 	libaudioflinger \
 	libaudiopolicyservice \
 	libbinder \
+	libcutils \
 	liblog \
 	libmedia \
+	libmedialogservice \
+	libnbaio \
 	libradioservice \
 	libsoundtriggerservice \
-	libutils \
+	libutils
 
 LOCAL_C_INCLUDES := \
 	frameworks/av/services/audioflinger \
@@ -22,6 +25,7 @@
 	frameworks/av/services/audiopolicy/common/include \
 	frameworks/av/services/audiopolicy/engine/interface \
 	frameworks/av/services/audiopolicy/service \
+	frameworks/av/services/medialog \
 	frameworks/av/services/radio \
 	frameworks/av/services/soundtrigger \
 	$(call include-path-for, audio-utils) \
diff --git a/media/audioserver/main_audioserver.cpp b/media/audioserver/main_audioserver.cpp
index a7123aa..698da1f 100644
--- a/media/audioserver/main_audioserver.cpp
+++ b/media/audioserver/main_audioserver.cpp
@@ -17,6 +17,11 @@
 #define LOG_TAG "audioserver"
 //#define LOG_NDEBUG 0
 
+#include <fcntl.h>
+#include <sys/prctl.h>
+#include <sys/wait.h>
+#include <cutils/properties.h>
+
 #include <binder/IPCThreadState.h>
 #include <binder/ProcessState.h>
 #include <binder/IServiceManager.h>
@@ -25,24 +30,105 @@
 // from LOCAL_C_INCLUDES
 #include "AudioFlinger.h"
 #include "AudioPolicyService.h"
+#include "MediaLogService.h"
 #include "RadioService.h"
 #include "SoundTriggerHwService.h"
 
 using namespace android;
 
-int main(int argc __unused, char **argv __unused)
+int main(int argc __unused, char **argv)
 {
     signal(SIGPIPE, SIG_IGN);
 
-    // TODO: add logging b/24511453#3
+    bool doLog = (bool) property_get_bool("ro.test_harness", 0);
 
-    sp<ProcessState> proc(ProcessState::self());
-    sp<IServiceManager> sm(defaultServiceManager());
-    ALOGI("ServiceManager: %p", sm.get());
-    AudioFlinger::instantiate();
-    AudioPolicyService::instantiate();
-    RadioService::instantiate();
-    SoundTriggerHwService::instantiate();
-    ProcessState::self()->startThreadPool();
-    IPCThreadState::self()->joinThreadPool();
+    pid_t childPid;
+    // FIXME The advantage of making the process containing media.log service the parent process of
+    // the process that contains the other audio services, is that it allows us to collect more
+    // detailed information such as signal numbers, stop and continue, resource usage, etc.
+    // But it is also more complex.  Consider replacing this by independent processes, and using
+    // binder on death notification instead.
+    if (doLog && (childPid = fork()) != 0) {
+        // media.log service
+        //prctl(PR_SET_NAME, (unsigned long) "media.log", 0, 0, 0);
+        // unfortunately ps ignores PR_SET_NAME for the main thread, so use this ugly hack
+        strcpy(argv[0], "media.log");
+        sp<ProcessState> proc(ProcessState::self());
+        MediaLogService::instantiate();
+        ProcessState::self()->startThreadPool();
+        for (;;) {
+            siginfo_t info;
+            int ret = waitid(P_PID, childPid, &info, WEXITED | WSTOPPED | WCONTINUED);
+            if (ret == EINTR) {
+                continue;
+            }
+            if (ret < 0) {
+                break;
+            }
+            char buffer[32];
+            const char *code;
+            switch (info.si_code) {
+            case CLD_EXITED:
+                code = "CLD_EXITED";
+                break;
+            case CLD_KILLED:
+                code = "CLD_KILLED";
+                break;
+            case CLD_DUMPED:
+                code = "CLD_DUMPED";
+                break;
+            case CLD_STOPPED:
+                code = "CLD_STOPPED";
+                break;
+            case CLD_TRAPPED:
+                code = "CLD_TRAPPED";
+                break;
+            case CLD_CONTINUED:
+                code = "CLD_CONTINUED";
+                break;
+            default:
+                snprintf(buffer, sizeof(buffer), "unknown (%d)", info.si_code);
+                code = buffer;
+                break;
+            }
+            struct rusage usage;
+            getrusage(RUSAGE_CHILDREN, &usage);
+            ALOG(LOG_ERROR, "media.log", "pid %d status %d code %s user %ld.%03lds sys %ld.%03lds",
+                    info.si_pid, info.si_status, code,
+                    usage.ru_utime.tv_sec, usage.ru_utime.tv_usec / 1000,
+                    usage.ru_stime.tv_sec, usage.ru_stime.tv_usec / 1000);
+            sp<IServiceManager> sm = defaultServiceManager();
+            sp<IBinder> binder = sm->getService(String16("media.log"));
+            if (binder != 0) {
+                Vector<String16> args;
+                binder->dump(-1, args);
+            }
+            switch (info.si_code) {
+            case CLD_EXITED:
+            case CLD_KILLED:
+            case CLD_DUMPED: {
+                ALOG(LOG_INFO, "media.log", "exiting");
+                _exit(0);
+                // not reached
+                }
+            default:
+                break;
+            }
+        }
+    } else {
+        // all other services
+        if (doLog) {
+            prctl(PR_SET_PDEATHSIG, SIGKILL);   // if parent media.log dies before me, kill me also
+            setpgid(0, 0);                      // but if I die first, don't kill my parent
+        }
+        sp<ProcessState> proc(ProcessState::self());
+        sp<IServiceManager> sm = defaultServiceManager();
+        ALOGI("ServiceManager: %p", sm.get());
+        AudioFlinger::instantiate();
+        AudioPolicyService::instantiate();
+        RadioService::instantiate();
+        SoundTriggerHwService::instantiate();
+        ProcessState::self()->startThreadPool();
+        IPCThreadState::self()->joinThreadPool();
+    }
 }
diff --git a/media/mediaserver/Android.mk b/media/mediaserver/Android.mk
index 979143c..107d2b6 100644
--- a/media/mediaserver/Android.mk
+++ b/media/mediaserver/Android.mk
@@ -16,7 +16,6 @@
 LOCAL_SHARED_LIBRARIES := \
 	libcamera_metadata\
 	libcameraservice \
-	libmedialogservice \
 	libresourcemanagerservice \
 	libcutils \
 	libmedia \
diff --git a/services/audioflinger/AudioFlinger.cpp b/services/audioflinger/AudioFlinger.cpp
index dbc6e6e..0a3a832 100644
--- a/services/audioflinger/AudioFlinger.cpp
+++ b/services/audioflinger/AudioFlinger.cpp
@@ -184,8 +184,7 @@
       mSystemReady(false)
 {
     getpid_cached = getpid();
-    // disable media.log until the service is reenabled, see b/26306954
-    const bool doLog = false; // property_get_bool("ro.test_harness", false);
+    const bool doLog = property_get_bool("ro.test_harness", false);
     if (doLog) {
         mLogMemoryDealer = new MemoryDealer(kLogMemorySize, "LogWriters",
                 MemoryHeapBase::READ_ONLY);
diff --git a/services/medialog/MediaLogService.cpp b/services/medialog/MediaLogService.cpp
index 41dab1f..98a71bb 100644
--- a/services/medialog/MediaLogService.cpp
+++ b/services/medialog/MediaLogService.cpp
@@ -28,7 +28,7 @@
 
 void MediaLogService::registerWriter(const sp<IMemory>& shared, size_t size, const char *name)
 {
-    if (IPCThreadState::self()->getCallingUid() != AID_MEDIA || shared == 0 ||
+    if (IPCThreadState::self()->getCallingUid() != AID_AUDIOSERVER || shared == 0 ||
             size < kMinSize || size > kMaxSize || name == NULL ||
             shared->size() < NBLog::Timeline::sharedSize(size)) {
         return;
@@ -41,7 +41,7 @@
 
 void MediaLogService::unregisterWriter(const sp<IMemory>& shared)
 {
-    if (IPCThreadState::self()->getCallingUid() != AID_MEDIA || shared == 0) {
+    if (IPCThreadState::self()->getCallingUid() != AID_AUDIOSERVER || shared == 0) {
         return;
     }
     Mutex::Autolock _l(mLock);
@@ -58,7 +58,7 @@
 {
     // FIXME merge with similar but not identical code at services/audioflinger/ServiceUtilities.cpp
     static const String16 sDump("android.permission.DUMP");
-    if (!(IPCThreadState::self()->getCallingUid() == AID_MEDIA ||
+    if (!(IPCThreadState::self()->getCallingUid() == AID_AUDIOSERVER ||
             PermissionCache::checkCallingPermission(sDump))) {
         dprintf(fd, "Permission Denial: can't dump media.log from pid=%d, uid=%d\n",
                 IPCThreadState::self()->getCallingPid(),