Revert "SERVER-41181 Fix sharding tests for hostname normalization"

This reverts commit 0ed0b97e6f62bba38cf4c93f5a7270569e79f24d (SERVER-41614).

5 files changed, 10 insertions, 26 deletions

diff --git a/jstests/aggregation/sources/collStats/shard_host_info.js b/jstests/aggregation/sources/collStats/shard_host_info.js
index aac6413167e..34e1d8a195e 100644
--- a/jstests/aggregation/sources/collStats/shard_host_info.js
+++ b/jstests/aggregation/sources/collStats/shard_host_info.js
@@ -14,7 +14,7 @@
     let testColl = testDB.test;
 
     // getHostName() doesn't include port, db.getMongo().host is 127.0.0.1:<port>
-    const hostName = (getHostName().toLowerCase() + ":" + db.getMongo().host.split(":")[1]);
+    const hostName = (getHostName() + ":" + db.getMongo().host.split(":")[1]);
 
     // Test that the shard field is absent and the host field is present when run on mongoD.
     assert.eq(testColl
@@ -41,10 +41,6 @@
     assert.commandWorked(
         testDB.adminCommand({shardCollection: testColl.getFullName(), key: {_id: "hashed"}}));
 
-    const getPrimary = (rs) => {
-        return rs.getPrimary().host.toLowerCase();
-    };
-
     // Group $collStats result by $shard and $host to confirm that both fields are present.
     assert.eq(testColl
                   .aggregate([
@@ -54,8 +50,8 @@
                   ])
                   .toArray(),
               [
-                {_id: {shard: st.shard0.shardName, host: getPrimary(st.rs0)}},
-                {_id: {shard: st.shard1.shardName, host: getPrimary(st.rs1)}},
+                {_id: {shard: st.shard0.shardName, host: st.rs0.getPrimary().host}},
+                {_id: {shard: st.shard1.shardName, host: st.rs1.getPrimary().host}},
               ]);
 
     st.stop();
diff --git a/jstests/sharding/aggregation_currentop.js b/jstests/sharding/aggregation_currentop.js
index f48a7af8fac..5e7ed32f09a 100644
--- a/jstests/sharding/aggregation_currentop.js
+++ b/jstests/sharding/aggregation_currentop.js
@@ -478,10 +478,6 @@ TestData.skipAwaitingReplicationOnShardsBeforeCheckingUUIDs = true;
     assert(clusterAdminDB.logout());
     assert(clusterAdminDB.auth("user_inprog", "pwd"));
 
-    const getPrimary = (rs) => {
-        return rs.getPrimary().host.toLowerCase();
-    };
-
     assert.eq(clusterAdminDB
                   .aggregate([
                       {$currentOp: {allUsers: true, idleConnections: true}},
@@ -490,9 +486,9 @@ TestData.skipAwaitingReplicationOnShardsBeforeCheckingUUIDs = true;
                   ])
                   .toArray(),
               [
-                {_id: {shard: "aggregation_currentop-rs0", host: getPrimary(st.rs0)}},
-                {_id: {shard: "aggregation_currentop-rs1", host: getPrimary(st.rs1)}},
-                {_id: {shard: "aggregation_currentop-rs2", host: getPrimary(st.rs2)}}
+                {_id: {shard: "aggregation_currentop-rs0", host: st.rs0.getPrimary().host}},
+                {_id: {shard: "aggregation_currentop-rs1", host: st.rs1.getPrimary().host}},
+                {_id: {shard: "aggregation_currentop-rs2", host: st.rs2.getPrimary().host}}
               ]);
 
     // Test that a $currentOp pipeline with {localOps:true} returns operations from the mongoS
@@ -873,7 +869,7 @@ TestData.skipAwaitingReplicationOnShardsBeforeCheckingUUIDs = true;
                   ])
                   .toArray(),
               [
-                {_id: {host: shardConn.host.toLowerCase()}},
+                {_id: {host: shardConn.host}},
               ]);
 
     // Test that attempting to 'spoof' a sharded request on non-shardsvr mongoD fails.
diff --git a/jstests/sharding/mongos_local_explain.js b/jstests/sharding/mongos_local_explain.js
index 4fd44f38150..bf9ab379e53 100644
--- a/jstests/sharding/mongos_local_explain.js
+++ b/jstests/sharding/mongos_local_explain.js
@@ -25,7 +25,7 @@
     // We expect the stages to appear under the 'mongos' heading, for 'splitPipeline' to be
     // null, and for the 'mongos.host' field to be the hostname:port of the mongoS itself.
     assert.docEq(explainPlan.mongos.stages, expectedExplainStages);
-    assert.eq(explainPlan.mongos.host.toLowerCase(), mongosConn.name.toLowerCase());
+    assert.eq(explainPlan.mongos.host, mongosConn.name);
     assert.isnull(explainPlan.splitPipeline);
 
     st.stop();
diff --git a/jstests/sharding/read_pref.js b/jstests/sharding/read_pref.js
index 1fd8e5b1185..99e662d57b1 100644
--- a/jstests/sharding/read_pref.js
+++ b/jstests/sharding/read_pref.js
@@ -58,7 +58,7 @@ TestData.skipCheckingUUIDsConsistentAcrossCluster = true;
             for (var idx = 0; idx < NODES; idx++) {
                 var node = replConf.members[idx];
 
-                if (node.host.toLowerCase() == nodeToCheck.toLowerCase()) {
+                if (node.host == nodeToCheck) {
                     jsTest.log('node[' + node.host + '], Tag: ' + tojson(node['tags']));
                     jsTest.log('tagToCheck: ' + tojson(tag));
 
@@ -125,7 +125,7 @@ TestData.skipCheckingUUIDsConsistentAcrossCluster = true;
         var getExplainServer = function(explain) {
             assert.eq("SINGLE_SHARD", explain.queryPlanner.winningPlan.stage);
             var serverInfo = explain.queryPlanner.winningPlan.shards[0].serverInfo;
-            return serverInfo.host.toLowerCase() + ":" + serverInfo.port.toString();
+            return serverInfo.host + ":" + serverInfo.port.toString();
         };
 
         // Read pref should work without slaveOk
diff --git a/src/mongo/util/net/socket_utils.cpp b/src/mongo/util/net/socket_utils.cpp
index 947f43a7c32..f58ff484ec7 100644
--- a/src/mongo/util/net/socket_utils.cpp
+++ b/src/mongo/util/net/socket_utils.cpp
@@ -62,8 +62,6 @@
 #include "mongo/util/str.h"
 #include "mongo/util/winutil.h"
 
-#include <string>
-
 namespace mongo {
 
 #if defined(_WIN32)
@@ -201,12 +199,6 @@ std::string getHostName() {
         log() << "can't get this server's hostname " << errnoWithDescription();
         return "";
     }
-
-    for (char* c = buf; *c; c++) {
-        // See https://en.cppreference.com/w/cpp/string/byte/tolower
-        *c = static_cast<char>(::tolower(static_cast<unsigned char>(*c)));
-    }
-
     return buf;
 }