[mac] update 'ToString()' methods to use string array (#6207)

src/core/mac/mac.cpp

@@ -2377,56 +2377,39 @@ void Mac::ResetRetrySuccessHistogram()
 
 const char *Mac::OperationToString(Operation aOperation)
 {
-    const char *retval = "";
-
-    switch (aOperation)
-    {
-    case kOperationIdle:
-        retval = "Idle";
-        break;
-
-    case kOperationActiveScan:
-        retval = "ActiveScan";
-        break;
-
-    case kOperationEnergyScan:
-        retval = "EnergyScan";
-        break;
-
-    case kOperationTransmitBeacon:
-        retval = "TransmitBeacon";
-        break;
-
-    case kOperationTransmitDataDirect:
-        retval = "TransmitDataDirect";
-        break;
-
+    static const char *const kOperationStrings[] = {
+        "Idle",               // (0) kOperationIdle
+        "ActiveScan",         // (1) kOperationActiveScan
+        "EnergyScan",         // (2) kOperationEnergyScan
+        "TransmitBeacon",     // (3) kOperationTransmitBeacon
+        "TransmitDataDirect", // (4) kOperationTransmitDataDirect
+        "TransmitPoll",       // (5) kOperationTransmitPoll
+        "WaitingForData",     // (6) kOperationWaitingForData
+        "TransmitOobFrame",   // (7) kOperationTransmitOutOfBandFrame
 #if OPENTHREAD_FTD
-    case kOperationTransmitDataIndirect:
-        retval = "TransmitDataIndirect";
-        break;
+        "TransmitDataIndirect", // (8) kOperationTransmitDataIndirect
+#if OPENTHREAD_CONFIG_MAC_CSL_TRANSMITTER_ENABLE
+        "TransmitDataCsl", // (9) kOperationTransmitDataCsl
+#endif
+#endif
+    };
 
-#if OPENTHREAD_FTD && OPENTHREAD_CONFIG_MAC_CSL_TRANSMITTER_ENABLE
-    case kOperationTransmitDataCsl:
-        retval = "TransmitDataCsl";
-        break;
+    static_assert(kOperationIdle == 0, "kOperationIdle value is incorrect");
+    static_assert(kOperationActiveScan == 1, "kOperationActiveScan value is incorrect");
+    static_assert(kOperationEnergyScan == 2, "kOperationEnergyScan value is incorrect");
+    static_assert(kOperationTransmitBeacon == 3, "kOperationTransmitBeacon value is incorrect");
+    static_assert(kOperationTransmitDataDirect == 4, "kOperationTransmitDataDirect value is incorrect");
+    static_assert(kOperationTransmitPoll == 5, "kOperationTransmitPoll value is incorrect");
+    static_assert(kOperationWaitingForData == 6, "kOperationWaitingForData value is incorrect");
+    static_assert(kOperationTransmitOutOfBandFrame == 7, "kOperationTransmitOutOfBandFrame value is incorrect");
+#if OPENTHREAD_FTD
+    static_assert(kOperationTransmitDataIndirect == 8, "kOperationTransmitDataIndirect value is incorrect");
+#if OPENTHREAD_CONFIG_MAC_CSL_TRANSMITTER_ENABLE
+    static_assert(kOperationTransmitDataCsl == 9, "TransmitDataCsl value is incorrect");
 #endif
 #endif
 
-    case kOperationTransmitPoll:
-        retval = "TransmitPoll";
-        break;
-
-    case kOperationWaitingForData:
-        retval = "WaitingForData";
-        break;
-
-    case kOperationTransmitOutOfBandFrame:
-        retval = "TransmitOobFrame";
-        break;
-    }
-
-    return retval;
+    return kOperationStrings[aOperation];
 }
 
 void Mac::LogFrameRxFailure(const RxFrame *aFrame, otError aError) const

src/core/mac/mac.hpp

@@ -754,22 +754,22 @@ private:
         kMaxAcquisitionId  = 0xffff,
     };
 
-    enum Operation
+    enum Operation : uint8_t
     {
         kOperationIdle = 0,
         kOperationActiveScan,
         kOperationEnergyScan,
         kOperationTransmitBeacon,
         kOperationTransmitDataDirect,
+        kOperationTransmitPoll,
+        kOperationWaitingForData,
+        kOperationTransmitOutOfBandFrame,
 #if OPENTHREAD_FTD
         kOperationTransmitDataIndirect,
 #if OPENTHREAD_CONFIG_MAC_CSL_TRANSMITTER_ENABLE
         kOperationTransmitDataCsl,
 #endif
 #endif
-        kOperationTransmitPoll,
-        kOperationWaitingForData,
-        kOperationTransmitOutOfBandFrame,
     };
 
 #if OPENTHREAD_CONFIG_MAC_RETRY_SUCCESS_HISTOGRAM_ENABLE

src/core/mac/sub_mac.cpp

@@ -859,66 +859,57 @@ exit:
 
 const char *SubMac::StateToString(State aState)
 {
-    const char *str = "Unknown";
-
-    switch (aState)
-    {
-    case kStateDisabled:
-        str = "Disabled";
-        break;
-    case kStateSleep:
-        str = "Sleep";
-        break;
-    case kStateReceive:
-        str = "Receive";
-        break;
-    case kStateCsmaBackoff:
-        str = "CsmaBackoff";
-        break;
-    case kStateTransmit:
-        str = "Transmit";
-        break;
-    case kStateEnergyScan:
-        str = "EnergyScan";
-        break;
+    static const char *const kStateStrings[] = {
+        "Disabled",    // (0) kStateDisabled
+        "Sleep",       // (1) kStateSleep
+        "Receive",     // (2) kStateReceive
+        "CsmaBackoff", // (3) kStateCsmaBackoff
+        "Transmit",    // (4) kStateTransmit
+        "EnergyScan",  // (5) kStateEnergyScan
 #if !OPENTHREAD_MTD && OPENTHREAD_CONFIG_MAC_CSL_TRANSMITTER_ENABLE
-    case kStateCslTransmit:
-        str = "CslTransmit";
-        break;
+        "CslTransmit", // (6) kStateCslTransmit
 #endif
 #if OPENTHREAD_CONFIG_MAC_CSL_RECEIVER_ENABLE
-    case kStateCslSample:
-        str = "CslSample";
-        break;
+        "CslSample", // (7) kStateCslSample
 #endif
-    }
+    };
 
-    return str;
+    static_assert(kStateDisabled == 0, "kStateDisabled value is not correct");
+    static_assert(kStateSleep == 1, "kStateSleep value is not correct");
+    static_assert(kStateReceive == 2, "kStateReceive value is not correct");
+    static_assert(kStateCsmaBackoff == 3, "kStateCsmaBackoff value is not correct");
+    static_assert(kStateTransmit == 4, "kStateTransmit value is not correct");
+    static_assert(kStateEnergyScan == 5, "kStateEnergyScan value is not correct");
+#if !OPENTHREAD_MTD && OPENTHREAD_CONFIG_MAC_CSL_TRANSMITTER_ENABLE
+    static_assert(kStateCslTransmit == 6, "kStateCslTransmit value is not correct");
+#if OPENTHREAD_CONFIG_MAC_CSL_RECEIVER_ENABLE
+    static_assert(kStateCslSample == 7, "kStateCslSample value is not correct");
+#endif
+#else
+#if OPENTHREAD_CONFIG_MAC_CSL_RECEIVER_ENABLE
+    static_assert(kStateCslSample == 6, "kStateCslSample value is not correct");
+#endif
+#endif
+
+    return kStateStrings[aState];
 }
 
 #if OPENTHREAD_CONFIG_MAC_CSL_RECEIVER_ENABLE
 const char *SubMac::CslStateToString(CslState aCslState)
 {
-    const char *str = "Unknown";
+    static const char *const kCslStateStrings[] = {
+        "CslIdle",   // (0) kCslIdle
+        "CslSample", // (1) kCslSample
+        "CslSleep",  // (2) kCslSleep
+    };
 
-    switch (aCslState)
-    {
-    case kCslIdle:
-        str = "CslIdle";
-        break;
-    case kCslSample:
-        str = "CslSample";
-        break;
-    case kCslSleep:
-        str = "kCslSleep";
-        break;
-    default:
-        break;
-    }
+    static_assert(kCslIdle == 0, "kCslIdle value is incorrect");
+    static_assert(kCslSample == 1, "kCslSample value is incorrect");
+    static_assert(kCslSleep == 2, "kCslSleep value is incorrect");
 
-    return str;
+    return kCslStateStrings[aCslState];
 }
-#endif // OPENTHREAD_CONFIG_MAC_CSL_RECEIVER_ENABLE
+#endif
 
 // LCOV_EXCL_STOP
 

src/core/mac/sub_mac.hpp

@@ -523,7 +523,7 @@ private:
 #endif
     };
 
-    enum State
+    enum State : uint8_t
     {
         kStateDisabled,    ///< Radio is disabled.
         kStateSleep,       ///< Radio is in sleep.