[cli] IPv6 counters (#6771)

Add CLI command for IPv6 packet success and failures during
transmission and reception.

src/cli/README.md

@@ -770,6 +770,7 @@ Get the supported counter names.
 
 ```bash
 > counters
+ip
 mac
 mle
 Done
@@ -824,6 +825,12 @@ Partition Id Changes: 1
 Better Partition Attach Attempts: 0
 Parent Changes: 0
 Done
+> counters ip
+TxSuccess: 10
+TxFailed: 0
+RxSuccess: 5
+RxFailed: 0
+Done
 ```
 
 ### counters \<countername\> reset
@@ -835,6 +842,8 @@ Reset the counter value.
 Done
 > counters mle reset
 Done
+> counters ip reset
+Done
 ```
 
 ### csl

src/cli/cli.cpp

@@ -1117,6 +1117,7 @@ otError Interpreter::ProcessCounters(Arg aArgs[])
 
     if (aArgs[0].IsEmpty())
     {
+        OutputLine("ip");
         OutputLine("mac");
         OutputLine("mle");
     }
@@ -1228,6 +1229,39 @@ otError Interpreter::ProcessCounters(Arg aArgs[])
             ExitNow(error = OT_ERROR_INVALID_ARGS);
         }
     }
+    else if (aArgs[0] == "ip")
+    {
+        if (aArgs[1].IsEmpty())
+        {
+            struct IpCounterName
+            {
+                const uint32_t otIpCounters::*mValuePtr;
+                const char *                  mName;
+            };
+
+            static const IpCounterName kCounterNames[] = {
+                {&otIpCounters::mTxSuccess, "TxSuccess"},
+                {&otIpCounters::mTxFailure, "TxFailed"},
+                {&otIpCounters::mRxSuccess, "RxSuccess"},
+                {&otIpCounters::mRxFailure, "RxFailed"},
+            };
+
+            const otIpCounters *ipCounters = otThreadGetIp6Counters(mInstance);
+
+            for (const IpCounterName &counter : kCounterNames)
+            {
+                OutputLine("%s: %d", counter.mName, ipCounters->*counter.mValuePtr);
+            }
+        }
+        else if ((aArgs[1] == "reset") && aArgs[2].IsEmpty())
+        {
+            otThreadResetIp6Counters(mInstance);
+        }
+        else
+        {
+            ExitNow(error = OT_ERROR_INVALID_ARGS);
+        }
+    }
     else
     {
         ExitNow(error = OT_ERROR_INVALID_ARGS);

tests/scripts/expect/cli-counters.exp

@@ -34,19 +34,26 @@ spawn_node 1
 send "counters\n"
 expect "mac"
 expect "mle"
+expect "ip"
 expect_line "Done"
 send "counters mac\n"
 expect_line "Done"
 send "counters mle\n"
 expect_line "Done"
+send "counters ip\n"
+expect_line "Done"
 send "counters mac reset\n"
 expect_line "Done"
 send "counters mle reset\n"
 expect_line "Done"
+send "counters ip reset\n"
+expect_line "Done"
 send "counters mac 1\n"
 expect "Error 7: InvalidArgs"
 send "counters mle 1\n"
 expect "Error 7: InvalidArgs"
+send "counters ip 1\n"
+expect "Error 7: InvalidArgs"
 send "counters other\n"
 expect "Error 7: InvalidArgs"