Initial support for inference cancellation

Infransctrure work to being able to send back and forth requests and
responses for inference cancellations.  The implementation is stubbed
to always fail in this commit.

Change-Id: Id7848930b81a3f38fe6c05323ccca2edd6b5b5bf

2 files changed, 26 insertions, 2 deletions

diff --git a/applications/message_handler/message_handler.cpp b/applications/message_handler/message_handler.cpp
index a634c16..f06d056 100644
--- a/applications/message_handler/message_handler.cpp
+++ b/applications/message_handler/message_handler.cpp
@@ -117,7 +117,7 @@ bool getNetwork(const uint32_t index, void *&data, size_t &size) {
 #endif
 
     default:
-        printf("Error: Network model index out of range. index=%u\n", index);
+        printf("Error: Network model index out of range. index=%" PRIu32 "\n", index);
         return true;
     }
 
@@ -131,7 +131,7 @@ bool getNetwork(const ethosu_core_network_buffer &buffer, void *&data, size_t &s
     case ETHOSU_CORE_NETWORK_INDEX:
         return getNetwork(buffer.index, data, size);
     default:
-        printf("Error: Unsupported network model type. type=%u\n", buffer.type);
+        printf("Error: Unsupported network model type. type=%" PRIu32 "\n", buffer.type);
         return true;
     }
 }
@@ -293,6 +293,19 @@ bool IncomingMessageHandler::handleMessage() {
         }
         break;
     }
+    case ETHOSU_CORE_MSG_CANCEL_INFERENCE_REQ: {
+        ethosu_core_cancel_inference_req req;
+        if (!inputMessageQueue.read(req)) {
+            sendErrorAndResetQueue(ETHOSU_CORE_MSG_ERR_INVALID_PAYLOAD, "CancelInferenceReq. Failed to read payload");
+            break;
+        }
+        printf("Msg: CancelInferenceReq. user_arg=0x%" PRIx64 ", inference_handle=0x%" PRIx64 "\n",
+               req.user_arg,
+               req.inference_handle);
+
+        sendCancelInferenceRsp(req.user_arg, ETHOSU_CORE_STATUS_ERROR);
+        break;
+    }
     case ETHOSU_CORE_MSG_NETWORK_INFO_REQ: {
         ethosu_core_network_info_req req;
         if (!inputMessageQueue.read(req)) {
@@ -393,6 +406,16 @@ void IncomingMessageHandler::sendFailedInferenceRsp(uint64_t userArg, uint32_t s
         mailbox.sendMessage();
     }
 }
+void IncomingMessageHandler::sendCancelInferenceRsp(uint64_t userArg, uint32_t status) {
+    ethosu_core_cancel_inference_rsp cancellation;
+    cancellation.user_arg = userArg;
+    cancellation.status   = status;
+    if (!outputMessageQueue.write(ETHOSU_CORE_MSG_CANCEL_INFERENCE_RSP, cancellation)) {
+        printf("ERROR: Msg: Failed to write cancel inference response. No mailbox message sent\n");
+    } else {
+        mailbox.sendMessage();
+    }
+}
 
 void IncomingMessageHandler::readCapabilties(ethosu_core_msg_capabilities_rsp &rsp) {
     rsp = {};
diff --git a/applications/message_handler/message_handler.hpp b/applications/message_handler/message_handler.hpp
index 60787e8..fa79205 100644
--- a/applications/message_handler/message_handler.hpp
+++ b/applications/message_handler/message_handler.hpp
@@ -59,6 +59,7 @@ private:
     void sendNetworkInfoRsp(uint64_t userArg, EthosU::ethosu_core_network_buffer &network);
     void sendInferenceRsp(EthosU::ethosu_core_inference_rsp &inference);
     void sendFailedInferenceRsp(uint64_t userArg, uint32_t status);
+    void sendCancelInferenceRsp(uint64_t userArg, uint32_t status);
     void readCapabilties(EthosU::ethosu_core_msg_capabilities_rsp &rsp);
 
     MessageQueue::QueueImpl inputMessageQueue;