Fix problem in lvm effect bundle wrapper.

When an effect is disabled, the process function should either
copy or accumulate the content of the input buffer to the output buffer
depending on the behavior requested by the framework.
Current implementation is copying the input buffer unconditionally.

Related to issue 5433942.

Change-Id: Ic488ca97eadcc4c763de570d7e6c6f5b7a979415

Author: Eric Laurent

media/libeffects/lvm/wrapper/Bundle/EffectBundle.cpp

@@ -49,6 +49,16 @@ extern "C" const struct effect_interface_s gLvmEffectInterface;
         }\
     }
 
+
+static inline int16_t clamp16(int32_t sample)
+{
+    // check overflow for both positive and negative values:
+    // all bits above short range must me equal to sign bit
+    if ((sample>>15) ^ (sample>>31))
+        sample = 0x7FFF ^ (sample>>31);
+    return sample;
+}
+
 // Namespaces
 namespace android {
 namespace {
@@ -707,13 +717,6 @@ int LvmBundle_init(EffectContext *pContext){
 }   /* end LvmBundle_init */
 
 
-static inline int16_t clamp16(int32_t sample)
-{
-    if ((sample>>15) ^ (sample>>31))
-        sample = 0x7FFF ^ (sample>>31);
-    return sample;
-}
-
 //----------------------------------------------------------------------------
 // LvmBundle_process()
 //----------------------------------------------------------------------------
@@ -2683,12 +2686,19 @@ int Effect_process(effect_handle_t     self,
             LOGV("\tLVM_ERROR : LvmBundle_process returned error %d", lvmStatus);
             return lvmStatus;
         }
-    }else{
+    } else {
         //LOGV("\tEffect_process Not Calling process with %d effects enabled, %d called: Effect %d",
         //pContext->pBundledContext->NumberEffectsEnabled,
         //pContext->pBundledContext->NumberEffectsCalled, pContext->EffectType);
         // 2 is for stereo input
-        memcpy(outBuffer->raw, inBuffer->raw, outBuffer->frameCount*sizeof(LVM_INT16)*2);
+        if (pContext->config.outputCfg.accessMode == EFFECT_BUFFER_ACCESS_ACCUMULATE) {
+            for (size_t i=0; i < outBuffer->frameCount*2; i++){
+                outBuffer->s16[i] =
+                        clamp16((LVM_INT32)outBuffer->s16[i] + (LVM_INT32)inBuffer->s16[i]);
+            }
+        } else {
+            memcpy(outBuffer->raw, inBuffer->raw, outBuffer->frameCount*sizeof(LVM_INT16)*2);
+        }
     }
 
     return status;