canbusutil: Permit definition of RTR frame length

can frame payload length indicates the length of the expected
response to the RTR frame. The actual payload value does
not matter. This permits the user to merely define the payload length.

Change-Id: I4517ef65f66367bbd8622561c5370a6bdaccf720
Reviewed-by: Rolf Eike Beer <eb@emlix.com>
Reviewed-by: Alex Blasche <alexander.blasche@theqtcompany.com>

1 files changed, 33 insertions, 16 deletions

diff --git a/src/tools/canbusutil/canbusutil.cpp b/src/tools/canbusutil/canbusutil.cpp
index ab845c3..ced63b6 100644
--- a/src/tools/canbusutil/canbusutil.cpp
+++ b/src/tools/canbusutil/canbusutil.cpp
@@ -80,8 +80,9 @@ void CanBusUtil::printUsage()
            << "<plugin>       plugin name to use. See --list-plugins." << endl
            << "<device>       device to use" << endl
            << "[data]         Data to send if -l is not specified. Format: " << endl
-           << "                   <id>#{R|payload}   (CAN 2.0 frames)," << endl
-           << "                   <id>##{payload}    (CAN FD frames)," << endl
+           << "                   <id>#{payload}   (CAN 2.0 data frames)," << endl
+           << "                   <id>#Rxx         (CAN 2.0 RTR frames with xx bytes data length)," << endl
+           << "                   <id>##{payload}  (CAN FD data frames)," << endl
            << "               where {payload} has 0..8 (0..64 CAN FD) ASCII hex-value pairs," << endl
            << "               e.g. 1#1a2b3c" << endl;
 }
@@ -97,8 +98,9 @@ void CanBusUtil::printPlugins()
 void CanBusUtil::printDataUsage()
 {
     output << "Invalid [data] field, use format: " << endl
-           << "    <id>#{R|payload}   (CAN 2.0 frames)," << endl
-           << "    <id>##{payload}    (CAN FD frames)," << endl
+           << "    <id>#{payload}   (CAN 2.0 data frames)," << endl
+           << "    <id>#Rxx         (CAN 2.0 RTR frames with xx bytes data length)," << endl
+           << "    <id>##{payload}  (CAN FD data frames)," << endl
            << "{payload} has 0..8 (0..64 CAN FD) ASCII hex-value pairs" << endl;
 }
 
@@ -152,17 +154,36 @@ bool CanBusUtil::parsePayloadField(QString payload, bool& rtrFrame,
                                    bool& fdFrame, QByteArray& bytes)
 {
     fdFrame = false;
+    rtrFrame = false;
 
     if (payload[0].toUpper() == 'R') {
         rtrFrame = true;
-        return true;
+        bool validPayloadLength = false;
+        if (payload.size() > 1) {
+            payload = payload.mid(1);
+            int rtrFrameLength = payload.toInt(&validPayloadLength);
+
+            if (validPayloadLength && rtrFrameLength > 0 && rtrFrameLength <= 64) {
+                bytes = QByteArray(rtrFrameLength, 0);
+                if (rtrFrameLength > 8)
+                    fdFrame = true;
+            } else if (validPayloadLength) {
+                output << "The length must be larger than 0 and not exceed 64." << endl;
+                validPayloadLength = false;
+            }
+        }
+
+        if (!validPayloadLength) {
+            output << "RTR data frame length not specified/valid." << endl;
+            printDataUsage();
+        }
+
+        return validPayloadLength;
     } else if (payload[0] == '#') {
         fdFrame = true;
-        payload = payload.right(payload.size() - 1);
+        payload = payload.mid(1);
     }
 
-    rtrFrame = false;
-
     if (payload.size() % 2 == 0) {
         for (int i=0; i < payload.size(); i+=2) {
             bool numberConverOk = true;
@@ -237,13 +258,11 @@ bool CanBusUtil::sendData()
     QByteArray bytes;
     QCanBusFrame frame;
 
-    if (parseDataField(id, payload) == false) {
+    if (parseDataField(id, payload) == false)
         return false;
-    }
 
-    if (parsePayloadField(payload, rtrFrame, fdFrame, bytes) == false) {
+    if (parsePayloadField(payload, rtrFrame, fdFrame, bytes) == false)
         return false;
-    }
 
     if (id > 0x7FF)  { //11 bits
         if (id > 0x1FFFFFFF) { // 29 bits
@@ -253,12 +272,10 @@ bool CanBusUtil::sendData()
         frame.setExtendedFrameFormat(true);
     }
 
-    if (rtrFrame) {
+    if (rtrFrame)
         frame.setFrameType(QCanBusFrame::RemoteRequestFrame);
-    } else {
-        frame.setPayload(bytes);
-    }
 
+    frame.setPayload(bytes);
     frame.setFrameId(id);
 
     if (fdFrame)