1 files changed, 61 insertions, 0 deletions
diff --git a/src/doppelganger/schedulingpolicyservice.cpp b/src/doppelganger/schedulingpolicyservice.cpp
new file mode 100644
index 0000000..641ddc4
--- /dev/null
+++ b/src/doppelganger/schedulingpolicyservice.cpp
@@ -0,0 +1,61 @@
+#include "schedulingpolicyservice.h"
+
+#include <binder/IServiceManager.h>
+#include <binder/IPCThreadState.h>
+#include <cutils/sched_policy.h>
+#include <sched.h>
+
+using namespace android;
+
+enum {
+    REQUEST_PRIORITY_TRANSACTION = IBinder::FIRST_CALL_TRANSACTION
+};
+
+#define PRIORITY_MIN 1
+#define PRIORITY_MAX 2
+
+SchedulingPolicyService::SchedulingPolicyService()
+{
+}
+
+void SchedulingPolicyService::instantiate()
+{
+    defaultServiceManager()->addService(String16("scheduling_policy"), new SchedulingPolicyService);
+}
+
+status_t SchedulingPolicyService::onTransact(uint32_t code, const Parcel &data, Parcel *reply, uint32_t flags)
+{
+    switch (code) {
+    case REQUEST_PRIORITY_TRANSACTION: {
+        CHECK_INTERFACE(ISchedulingPolicyService, data, reply);
+        int32_t pid = data.readInt32();
+        int32_t tid = data.readInt32();
+        int32_t prio = data.readInt32();
+        int res = requestPriority(pid, tid, prio);
+        reply->writeNoException();
+        reply->writeInt32(res);
+        return NO_ERROR;
+    } break;
+    default:
+        return BBinder::onTransact(code, data, reply, flags);
+    }
+}
+
+int SchedulingPolicyService::requestPriority(int32_t pid, int32_t tid, int32_t prio)
+{
+    if (prio < PRIORITY_MIN || prio > PRIORITY_MAX)
+        return PERMISSION_DENIED;
+
+    int res = set_sched_policy(tid, IPCThreadState::self()->getCallingPid() == pid ? SP_AUDIO_SYS
+                                                                                   : SP_AUDIO_APP);
+    if (res != NO_ERROR)
+        return PERMISSION_DENIED;
+
+    struct sched_param param;
+    param.sched_priority = prio;
+    res = sched_setscheduler(tid, SCHED_FIFO, &param);
+    if (res)
+        return PERMISSION_DENIED;
+
+    return OK;
+}