From 0e7c9559ecc4ba329d205f6812195f11b04cee63 Mon Sep 17 00:00:00 2001
From: Shane Freeder <theboyetronic@gmail.com>
Date: Sat, 12 Jan 2019 13:59:06 +0000
Subject: [PATCH] Address some issues with book limits (#1798)

The multibyte calculation has been fixed, now we actually work out which
characters take more than a byte.

Diminishing returns has been modified, previously the multiplier would zero
itself out due to floating point limitations
---
 Spigot-Server-Patches/Book-Size-Limits.patch  | 37 +++++++++++++------
 .../Fix-PlayerEditBookEvent.patch             |  2 +-
 2 files changed, 26 insertions(+), 13 deletions(-)

diff --git a/Spigot-Server-Patches/Book-Size-Limits.patch b/Spigot-Server-Patches/Book-Size-Limits.patch
index e07f2c5877..01800cec4b 100644
--- a/Spigot-Server-Patches/Book-Size-Limits.patch
+++ b/Spigot-Server-Patches/Book-Size-Limits.patch
@@ -22,9 +22,18 @@ index fef899ae0..468aff713 100644
 +    }
  }
 diff --git a/src/main/java/net/minecraft/server/PlayerConnection.java b/src/main/java/net/minecraft/server/PlayerConnection.java
-index 7ae374085..bbdf729c3 100644
+index cb6d1deb8..8d06b23ea 100644
 --- a/src/main/java/net/minecraft/server/PlayerConnection.java
 +++ b/src/main/java/net/minecraft/server/PlayerConnection.java
+@@ -0,0 +0,0 @@ import java.util.Collections;
+ import java.util.Iterator;
+ import java.util.Set;
+ import javax.annotation.Nullable;
++
++import org.apache.commons.lang3.StringEscapeUtils;
+ import org.apache.commons.lang3.StringUtils;
+ import org.apache.logging.log4j.LogManager;
+ import org.apache.logging.log4j.Logger;
 @@ -0,0 +0,0 @@ public class PlayerConnection implements PacketListenerPlayIn, ITickable {
      }
  
@@ -41,24 +50,28 @@ index 7ae374085..bbdf729c3 100644
 +                String testString = pageList.getString(i);
 +                int byteLength = testString.getBytes(java.nio.charset.StandardCharsets.UTF_8).length;
 +                byteTotal += byteLength;
-+                if (byteTotal > byteAllowed) {
-+                    PlayerConnection.LOGGER.warn(this.player.getName() + " tried to send too large of a book. Book Size: " + byteTotal + " - Allowed:  "+ byteAllowed + " - Pages: " + pageList.size());
-+                    minecraftServer.postToMainThread(() -> this.disconnect("Book too large!"));
-+                    return;
-+                }
 +                int length = testString.length();
-+                int multibytes = byteLength == length ? byteLength : (int) Math.round((double) byteLength / (double) length);
-+                for (int x = 1; x < multibytes; x++) {
-+                    multiplier *= multiplier;
++                int multibytes = 0;
++                if (byteLength != length) {
++                    for (char c : testString.toCharArray()) {
++                        if (c > 127) {
++                            multibytes++;
++                        }
++                    }
 +                }
 +                byteAllowed += (maxBookPageSize * Math.min(1, Math.max(0.1D, (double) length / 255D))) * multiplier;
-+                multiplier *= multiplier;
 +
 +                if (multibytes > 1) {
-+                    // penalize MB some more
-+                    byteAllowed -= length;
++                    // penalize MB
++                    byteAllowed -= multibytes;
 +                }
 +            }
++
++            if (byteTotal > byteAllowed) {
++                PlayerConnection.LOGGER.warn(this.player.getName() + " tried to send too large of a book. Book Size: " + byteTotal + " - Allowed:  "+ byteAllowed + " - Pages: " + pageList.size());
++                minecraftServer.postToMainThread(() -> this.disconnect("Book too large!"));
++                return;
++            }
 +        }
 +        // Paper end
          // CraftBukkit start
diff --git a/Spigot-Server-Patches/Fix-PlayerEditBookEvent.patch b/Spigot-Server-Patches/Fix-PlayerEditBookEvent.patch
index 804d9e0819..6423deeadb 100644
--- a/Spigot-Server-Patches/Fix-PlayerEditBookEvent.patch
+++ b/Spigot-Server-Patches/Fix-PlayerEditBookEvent.patch
@@ -10,7 +10,7 @@ it impossible to properly cancel the event or modify the book meta
 cancelled writing
 
 diff --git a/src/main/java/net/minecraft/server/PlayerConnection.java b/src/main/java/net/minecraft/server/PlayerConnection.java
-index 74c570615..9741d3b23 100644
+index 8d06b23ea..a8a6e236e 100644
 --- a/src/main/java/net/minecraft/server/PlayerConnection.java
 +++ b/src/main/java/net/minecraft/server/PlayerConnection.java
 @@ -0,0 +0,0 @@ public class PlayerConnection implements PacketListenerPlayIn, ITickable {