remote-proccessor detect partial message reception

BZ: 190038

Client disconnection during message reception is normal if no part of the
message as been receive yet.
Client disconnection in the middle of a packet reception is not normal
but was not differentiated from the behaviour described above.

Do not consider client disconnection on first read as an error.
Consider it as an error on the followings.

Change-Id: I34b50ba0af800f9e1fcdb51996b1b2f02a23cb3f
Signed-off-by: Kevin Rocard <kevinx.rocard@intel.com>
Signed-off-by: Mattijs Korpershoek <mattijsx.korpershoek@intel.com>

3 files changed, 57 insertions, 33 deletions

diff --git a/remote-processor/Message.cpp b/remote-processor/Message.cpp
index db24d80..8591847 100644
--- a/remote-processor/Message.cpp
+++ b/remote-processor/Message.cpp
@@ -124,7 +124,7 @@ uint32_t CMessage::getRemainingDataSize() const
 }
 
 // Send/Receive
-bool CMessage::serialize(CSocket* pSocket, bool bOut, string& strError)
+CMessage::Result CMessage::serialize(CSocket* pSocket, bool bOut, string& strError)
 {
     if (bOut) {
 
@@ -142,8 +142,10 @@ bool CMessage::serialize(CSocket* pSocket, bool bOut, string& strError)
 
         if (!pSocket->write(&uiSyncWord, sizeof(uiSyncWord))) {
 
-            strError += string("Sync write failed: ") + strerror(errno);
-            return false;
+            if (pSocket->hasPeerDisconnected()) {
+                return peerDisconnected;
+            }
+            return error;
         }
 
         // Size
@@ -152,21 +154,21 @@ bool CMessage::serialize(CSocket* pSocket, bool bOut, string& strError)
         if (!pSocket->write(&uiSize, sizeof(uiSize))) {
 
             strError += string("Size write failed: ") + strerror(errno);
-            return false;
+            return error;
         }
 
         // Msg Id
         if (!pSocket->write(&_ucMsgId, sizeof(_ucMsgId))) {
 
             strError += string("Msg write failed: ") + strerror(errno);
-            return false;
+            return error;
         }
 
         // Data
         if (!pSocket->write(_pucData, _uiDataSize)) {
 
             strError = string("Data write failed: ") + strerror(errno);
-            return false;
+            return error;
         }
 
         // Checksum
@@ -175,7 +177,7 @@ bool CMessage::serialize(CSocket* pSocket, bool bOut, string& strError)
         if (!pSocket->write(&ucChecksum, sizeof(ucChecksum))) {
 
             strError = string("Checksum write failed: ") + strerror(errno);
-            return false;
+            return error;
         }
 
     } else {
@@ -185,14 +187,17 @@ bool CMessage::serialize(CSocket* pSocket, bool bOut, string& strError)
         if (!pSocket->read(&uiSyncWord, sizeof(uiSyncWord))) {
 
             strError = string("Sync read failed: ") + strerror(errno);
-            return false;
+            if (pSocket->hasPeerDisconnected()) {
+                return peerDisconnected;
+            }
+            return error;
         }
 
         // Check Sync word
         if (uiSyncWord != SYNC_WORD) {
 
             strError = "Sync word incorrect";
-            return false;
+            return error;
         }
 
         // Size
@@ -201,14 +206,14 @@ bool CMessage::serialize(CSocket* pSocket, bool bOut, string& strError)
         if (!pSocket->read(&uiSize, sizeof(uiSize))) {
 
             strError = string("Size read failed: ") + strerror(errno);
-            return false;
+            return error;
         }
 
         // Msg Id
         if (!pSocket->read(&_ucMsgId, sizeof(_ucMsgId))) {
 
             strError = string("Msg id read failed: ") + strerror(errno);
-            return false;
+            return error;
         }
 
         // Data
@@ -220,7 +225,7 @@ bool CMessage::serialize(CSocket* pSocket, bool bOut, string& strError)
         if (!pSocket->read(_pucData, _uiDataSize)) {
 
             strError = string("Data read failed: ") + strerror(errno);
-            return false;
+            return error;
         }
 
         // Checksum
@@ -229,20 +234,20 @@ bool CMessage::serialize(CSocket* pSocket, bool bOut, string& strError)
         if (!pSocket->read(&ucChecksum, sizeof(ucChecksum))) {
 
             strError = string("Checksum read failed: ") + strerror(errno);
-            return false;
+            return error;
         }
         // Compare
         if (ucChecksum != computeChecksum()) {
 
             strError = "Received checksum != computed checksum";
-            return false;
+            return error;
         }
 
         // Collect data in derived
         collectReceivedData();
     }
 
-    return true;
+    return success;
 }
 
 // Checksum
diff --git a/remote-processor/Message.h b/remote-processor/Message.h
index 4f22977..feafc83 100644
--- a/remote-processor/Message.h
+++ b/remote-processor/Message.h
@@ -43,6 +43,12 @@ public:
     CMessage();
     virtual ~CMessage();
 
+    enum Result {
+        success,
+        peerDisconnected,
+        error
+    };
+
     /** Write or read the message on pSocket.
      *
      * @param[in,out] pSocket is the socket on wich IO operation will be made.
@@ -51,9 +57,11 @@ public:
      * @param[out] strError on failure, a string explaining the error,
      *                      on success, undefined.
      *
-     * @return true on success, false on failure.
+     * @return success if a correct message could be recv/send
+     *         peerDisconnected if the peer disconnected before the first socket access.
+     *         error if the message could not be read/write for any other reason
      */
-    bool serialize(CSocket* pSocket, bool bOut, std::string &strError);
+    Result serialize(CSocket* pSocket, bool bOut, std::string &strError);
 
 protected:
     // Msg Id
diff --git a/remote-processor/RemoteProcessorServer.cpp b/remote-processor/RemoteProcessorServer.cpp
index 487379e..8c66109 100644
--- a/remote-processor/RemoteProcessorServer.cpp
+++ b/remote-processor/RemoteProcessorServer.cpp
@@ -30,6 +30,7 @@
 #include "RemoteProcessorServer.h"
 #include "ListeningSocket.h"
 #include <iostream>
+#include <memory>
 #include <assert.h>
 #include <poll.h>
 #include <unistd.h>
@@ -147,15 +148,15 @@ void CRemoteProcessorServer::run()
 // New connection
 void CRemoteProcessorServer::handleNewConnection()
 {
-    CSocket* pClientSocket = _pListeningSocket->accept();
+    const auto_ptr<CSocket> clientSocket(_pListeningSocket->accept());
 
-    if (!pClientSocket) {
+    if (clientSocket.get() == NULL) {
 
         return;
     }
 
     // Set timeout
-    pClientSocket->setTimeout(5000);
+    clientSocket->setTimeout(5000);
 
     // Process all incoming requests from the client
     while (true) {
@@ -166,12 +167,18 @@ void CRemoteProcessorServer::handleNewConnection()
 
         string strError;
         ///// Receive command
-        if (!requestMessage.serialize(pClientSocket, false, strError)) {
-
-            if (!pClientSocket->hasPeerDisconnected()) {
-                cout << "Error while receiving message: " << strError << endl;
-            }
-            break;
+        CRequestMessage::Result res;
+        res = requestMessage.serialize(clientSocket.get(), false, strError);
+
+        switch (res) {
+        case CRequestMessage::error:
+            cout << "Error while receiving message: " << strError << endl;
+            // fall through
+        case CRequestMessage::peerDisconnected:
+            // Consider peer disconnection as normal, no log
+            return; // Bail out
+        case CRequestMessage::success:
+            break; // No error, continue
         }
 
         // Actually process the request
@@ -195,13 +202,17 @@ void CRemoteProcessorServer::handleNewConnection()
         CAnswerMessage answerMessage(strResult, bSuccess);
 
         ///// Send answer
-        if (!answerMessage.serialize(pClientSocket, true, strError)) {
-
-            // Bail out
-            cout << "Error while sending message: " << strError << endl;
-            break;
+        res = answerMessage.serialize(clientSocket.get(), true, strError);
+
+        switch (res) {
+        case CRequestMessage::peerDisconnected:
+            // Peer should not disconnect while waiting for an answer
+            // Fall through to log the error and bail out
+        case CRequestMessage::error:
+            cout << "Error while receiving message: " << strError << endl;
+            return; // Bail out
+        case CRequestMessage::success:
+            break; // No error, continue
         }
     }
-    // Remove client socket
-    delete pClientSocket;
 }