Server run profile, also setup logging for client profile.

build.gradle

@@ -163,6 +163,8 @@ project(':forge') {
         installer 'org.apache.maven:maven-artifact:3.5.3'
         installer 'net.jodah:typetools:0.5.0'
         installer 'java3d:vecmath:1.5.2'
+        installer 'org.apache.logging.log4j:log4j-api:2.11.1'
+        installer 'org.apache.logging.log4j:log4j-core:2.11.1'
     }
 
     task runclient(type: JavaExec, dependsOn: [":forge:downloadAssets", ":forge:extractNatives"]) {
@@ -344,7 +346,16 @@ project(':forge') {
                 type: 'release',
                 mainClass: 'cpw.mods.modlauncher.Launcher',
                 inheritsFrom: MC_VERSION,
-                logging: [:],
+                logging: [ client: [
+                        argument: '-Dlog4j.configurationFile=${path}',
+                        file: [
+                                id:'client-1.12.xml',
+                                sha1:'ef4f57b922df243d0cef096efe808c72db042149',
+                                size:877,
+                                url:'https://launcher.mojang.com/v1/objects/ef4f57b922df243d0cef096efe808c72db042149/client-1.12.xml'
+                        ],
+                        type: 'log4j2-xml'
+                ]],
                 arguments: [
                     game: ['--launchTarget', 'fmlclient']
                 ],
@@ -545,7 +556,9 @@ project(':forge') {
             artifacts.each { key, lib ->
                 classpath += "libraries/${lib.downloads.artifact.path} "
             }
-            classpath += "minecraft_server.${MC_VERSION}.jar"
+            classpath += "libraries/net/minecraft/server/${MC_VERSION}/server-${MC_VERSION}-data.jar "
+            classpath += "libraries/net/minecraft/server/${MC_VERSION}/server-${MC_VERSION}-extra.jar"
+            
             
             manifest.attributes([
                 'Main-Class': 'net.minecraftforge.server.ServerMain',

patches/minecraft/net/minecraft/client/gui/GuiConnecting.java.patch

@@ -0,0 +1,10 @@
+--- a/net/minecraft/client/gui/GuiConnecting.java
++++ b/net/minecraft/client/gui/GuiConnecting.java
+@@ -62,6 +62,7 @@
+                GuiConnecting.this.field_146371_g.func_150719_a(new NetHandlerLoginClient(GuiConnecting.this.field_146371_g, GuiConnecting.this.field_146297_k, GuiConnecting.this.field_146374_i, (p_209549_1_) -> {
+                   GuiConnecting.this.func_209514_a(p_209549_1_);
+                }));
++               net.minecraftforge.fml.network.NetworkHooks.registerClientLoginChannel(GuiConnecting.this.field_146371_g);
+                GuiConnecting.this.field_146371_g.func_179290_a(new CPacketHandshake(p_146367_1_, p_146367_2_, EnumConnectionState.LOGIN));
+                GuiConnecting.this.field_146371_g.func_179290_a(new CPacketLoginStart(GuiConnecting.this.field_146297_k.func_110432_I().func_148256_e()));
+             } catch (UnknownHostException unknownhostexception) {

src/main/java/net/minecraftforge/fml/loading/FMLServerLaunchProvider.java

@@ -0,0 +1,81 @@
+/*
+ * Minecraft Forge
+ * Copyright (c) 2016-2018.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation version 2.1
+ * of the License.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ */
+
+package net.minecraftforge.fml.loading;
+
+import cpw.mods.modlauncher.api.IEnvironment;
+import cpw.mods.modlauncher.api.ILaunchHandlerService;
+import cpw.mods.modlauncher.api.ITransformingClassLoader;
+import net.minecraftforge.api.distmarker.Dist;
+import net.minecraftforge.versions.forge.ForgeVersion;
+import net.minecraftforge.versions.mcp.MCPVersion;
+import org.apache.logging.log4j.LogManager;
+import org.apache.logging.log4j.Logger;
+
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.util.concurrent.Callable;
+
+public class FMLServerLaunchProvider extends FMLCommonLaunchHandler implements ILaunchHandlerService
+{
+    private static final Logger LOGGER = LogManager.getLogger();
+
+    @Override
+    public String name()
+    {
+        return "fmlserver";
+    }
+
+    @Override
+    public Path[] identifyTransformationTargets()
+    {
+        Path libsPath = findLibsPath();
+        Path patchedBinariesPath = libsPath.resolve(Paths.get("net","minecraftforge","forge",MCPVersion.getMCVersion()+"-"+ForgeVersion.getVersion(),"forge-"+MCPVersion.getMCVersion()+"-"+ForgeVersion.getVersion()+"-server.jar"));
+        Path srgMcPath = libsPath.resolve(Paths.get("net","minecraft", "server", MCPVersion.getMCPandMCVersion(), "server-"+MCPVersion.getMCPandMCVersion()+"-srg.jar"));
+        LOGGER.info("SRG MC at {} is {}", srgMcPath.toString(), Files.exists(srgMcPath) ? "present" : "missing");
+        LOGGER.info("Forge patches at {} is {}", patchedBinariesPath.toString(), Files.exists(patchedBinariesPath) ? "present" : "missing");
+        LOGGER.info("Forge at {} is {}", getForgePath().toString(), Files.exists(getForgePath()) ? "present" : "missing");
+        if (!(Files.exists(srgMcPath) && Files.exists(patchedBinariesPath) && Files.exists(getForgePath()))) {
+            throw new RuntimeException("Failed to find patched jars");
+        }
+        return new Path[] {getForgePath(), patchedBinariesPath, srgMcPath};
+    }
+
+    @Override
+    public Callable<Void> launchService(String[] arguments, ITransformingClassLoader launchClassLoader)
+    {
+        return () -> {
+            super.beforeStart(launchClassLoader);
+            launchClassLoader.addTargetPackageFilter(getPackagePredicate());
+            Class.forName("net.minecraft.server.MinecraftServer", true, launchClassLoader.getInstance()).getMethod("main", String[].class).invoke(null, (Object)arguments);
+            return null;
+        };
+    }
+
+    @Override
+    public void setup(final IEnvironment environment) {
+    }
+
+    @Override
+    public Dist getDist()
+    {
+        return Dist.DEDICATED_SERVER;
+    }
+}

src/main/java/net/minecraftforge/server/ServerMain.java

@@ -0,0 +1,11 @@
+package net.minecraftforge.server;
+
+import com.google.common.collect.ObjectArrays;
+import cpw.mods.modlauncher.Launcher;
+
+public class ServerMain {
+    public static void main(String[] args) {
+        final String[] argArray = ObjectArrays.concat(new String[]{"--launchTarget", "fmlserver","--gameDir", "."}, args, String.class);
+        Launcher.main(argArray);
+    }
+}

src/main/resources/META-INF/services/cpw.mods.modlauncher.api.ILaunchHandlerService

@@ -1,3 +1,4 @@
 net.minecraftforge.fml.loading.FMLClientLaunchProvider
+net.minecraftforge.fml.loading.FMLServerLaunchProvider
 net.minecraftforge.fml.loading.FMLDevClientLaunchProvider
 net.minecraftforge.fml.loading.FMLDevServerLaunchProvider