From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Professor Bloodstone <git@bloodstone.dev>
Date: Sun, 20 Jun 2021 01:48:31 +0200
Subject: [PATCH] Add Git information to version command/on startup


diff --git a/src/main/java/io/papermc/paper/util/JarManifests.java b/src/main/java/io/papermc/paper/util/JarManifests.java
new file mode 100644
index 0000000000000000000000000000000000000000..02ad04c41b9c3ec68b1dcdc22c538340d8d3455b
--- /dev/null
+++ b/src/main/java/io/papermc/paper/util/JarManifests.java
@@ -0,0 +1,93 @@
+/*
+Copyright (c) 2012-2017, jcabi.com
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions
+are met: 1) Redistributions of source code must retain the above
+copyright notice, this list of conditions and the following
+disclaimer. 2) Redistributions in binary form must reproduce the above
+copyright notice, this list of conditions and the following
+disclaimer in the documentation and/or other materials provided
+with the distribution. 3) Neither the name of the jcabi.com nor
+the names of its contributors may be used to endorse or promote
+products derived from this software without specific prior written
+permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT
+NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
+FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
+OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+package io.papermc.paper.util;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URL;
+import java.util.*;
+import java.util.jar.Manifest;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Modified version of jcabi-manifests
+ *
+ */
+public final class JarManifests {
+
+    public static final JarManifests JAR_MANIFESTS = new JarManifests();
+    public static final Map<String, String> MANIFEST_MAP;
+
+    static {
+        try {
+            MANIFEST_MAP = Collections.unmodifiableMap(JAR_MANIFESTS.getManifestMap());
+        } catch (final IOException ex) {
+            throw new RuntimeException(ex);
+        }
+    }
+
+    private JarManifests() {}
+
+    // Based on:
+    // https://github.com/jcabi/jcabi-manifests/blob/c4e1dd22bb6099769b8d279ebe3737e5b638b278/src/main/java/com/jcabi/manifests/ClasspathMfs.java#L49-L58
+
+    /**
+     * Get collection containing all META-INF/MANIFEST.MF streams
+     *
+     * @throws IOException if unable to get resources from classloader
+     */
+    public @NotNull Collection<@NotNull InputStream> getManifestStreams() throws IOException {
+        final Enumeration<URL> resources = getClass().getClassLoader().getResources("META-INF/MANIFEST.MF");
+        final Collection<InputStream> streams = new ArrayList<>(1);
+        while (resources.hasMoreElements()) {
+            streams.add(resources.nextElement().openStream());
+        }
+        return streams;
+    }
+
+    // Based on:
+    // https://github.com/jcabi/jcabi-manifests/blob/c4e1dd22bb6099769b8d279ebe3737e5b638b278/src/main/java/com/jcabi/manifests/Manifests.java#L209-L225
+    // https://github.com/jcabi/jcabi-manifests/blob/c4e1dd22bb6099769b8d279ebe3737e5b638b278/src/main/java/com/jcabi/manifests/Manifests.java#L381-L388
+
+    /**
+     * Get map containing entries from all manifests
+     *
+     * @throws IOException if unable to get manifest streams
+     */
+    public @NotNull Map<@NotNull String, @NotNull String> getManifestMap() throws IOException {
+        final HashMap<String, String> attribs = new HashMap<>();
+        for (final InputStream stream : getManifestStreams()) {
+            for (final Map.Entry<Object, Object> attr: new Manifest(stream).getMainAttributes().entrySet()) {
+                attribs.put(attr.getKey().toString(), attr.getValue().toString());
+            }
+        }
+        return attribs;
+    }
+}
diff --git a/src/main/java/org/bukkit/Bukkit.java b/src/main/java/org/bukkit/Bukkit.java
index 071a0013ac4bad6483c1400e8eb7b842fa1b7496..66580ade2cd8b8795b2d79f7958460162c3a17db 100644
--- a/src/main/java/org/bukkit/Bukkit.java
+++ b/src/main/java/org/bukkit/Bukkit.java
@@ -50,6 +50,7 @@ import org.bukkit.util.CachedServerIcon;
 import org.jetbrains.annotations.Contract;
 import org.jetbrains.annotations.NotNull;
 import org.jetbrains.annotations.Nullable;
+import io.papermc.paper.util.JarManifests; // Paper
 
 /**
  * Represents the Bukkit core, for version and Server singleton handling
@@ -85,7 +86,25 @@ public final class Bukkit {
         }
 
         Bukkit.server = server;
-        server.getLogger().info("This server is running " + getName() + " version " + getVersion() + " (Implementing API version " + getBukkitVersion() + ")");
+        // Paper start - add git information
+        server.getLogger().info(getVersionMessage());
+    }
+    /**
+      * Gets message describing the version server is running.
+      *
+      * @return message describing the version server is running
+      */
+    @NotNull
+    public static String getVersionMessage() {
+        Map<String, String> attributes = JarManifests.MANIFEST_MAP;
+        @NotNull String gitBranch = attributes.get("Git-Branch");
+        @NotNull String gitCommit = attributes.get("Git-Commit");
+        @NotNull String branchMsg = " on " + gitBranch;
+        if ("master".equals(gitBranch) || "main".equals(gitBranch)) {
+            branchMsg = "";  // Don't show branch on main/master
+        }
+        return "This server is running " + getName() + " version " + getVersion() + " (Implementing API version " + getBukkitVersion() + ") (Git: " + gitCommit + branchMsg + ")";
+        // Paper end
     }
 
     /**
diff --git a/src/main/java/org/bukkit/command/defaults/VersionCommand.java b/src/main/java/org/bukkit/command/defaults/VersionCommand.java
index 4c2ddc722a9dc4011906ad9530b13fa9be1d3ff9..57a21495843f3a144cd73473cdc8781d6129b7ca 100644
--- a/src/main/java/org/bukkit/command/defaults/VersionCommand.java
+++ b/src/main/java/org/bukkit/command/defaults/VersionCommand.java
@@ -241,7 +241,7 @@ public class VersionCommand extends BukkitCommand {
     private void setVersionMessage(final @NotNull Component msg) {
         lastCheck = System.currentTimeMillis();
         final Component message = net.kyori.adventure.text.TextComponent.ofChildren(
-            Component.text("This server is running " + Bukkit.getName() + " version " + Bukkit.getVersion() + " (Implementing API version " + Bukkit.getBukkitVersion() + ")", net.kyori.adventure.text.format.NamedTextColor.WHITE),
+            Component.text(Bukkit.getVersionMessage(), net.kyori.adventure.text.format.NamedTextColor.WHITE),
             Component.newline(),
             msg
         );
