In the efforts to preserve old versions of Minecraft Forge, we've been taking steps to update the toolchain.
One of these steps includes backporting the newer MCPConfig data format, so that these old versions have a form of data that is representable by the newer systems.
This is step one to compatibility with the newer ForgeGradle systems.
The purpose of MCPUpdater is to grab and transform the antiquated MCP data formats, with the following inclusions:
The MCP patch format is as such:
- minecraft_ff/net.minecraft.advancements.Advancement.java.patch
- minecraft_merged_ff/net.minecraft.advancements.Advancement.java.patch
- minecraft_server_ff/net.minecraft.advancements.Advancement.java.patch
The MCP patches start with the header:
diff -r -U 3 minecraft\net\minecraft\advancements\AdvancementList.java minecraft_patched\net\minecraft\advancements\AdvancementList.java
--- minecraft\net\minecraft\advancements\AdvancementList.java
+++ minecraft_patched\net\minecraft\advancements\AdvancementList.java
diff -r -U 3 minecraft\net\minecraft\advancements\AdvancementList.java minecraft_patched\net\minecraft\advancements\AdvancementList.java
--- minecraft\net\minecraft\advancements\AdvancementList.java
+++ minecraft_patched\net\minecraft\advancements\AdvancementList.java
diff -r -U 3 minecraft_server\net\minecraft\advancements\AdvancementList.java minecraft_server_patched\net\minecraft\advancements\AdvancementList.java
--- minecraft_server\net\minecraft\advancements\AdvancementList.java
+++ minecraft_server_patched\net\minecraft\advancements\AdvancementList.java
The MCPConfig patch format is as such:
- patches/client/net/minecraft/advancements/Advancement.java.patch
- patches/joined/net/minecraft/advancements/Advancement.java.patch
- patches/server/net/minecraft/advancements/Advancement.java.patch
The MCPConfig patches start with the header:
--- a/net/minecraft/advancements/AdvancementList.java
+++ b/net/minecraft/advancements/AdvancementList.java
The MCP data uses a file called joined.exc to encode data about constructor parameter naming, function access and exceptions thrown.
The EXC format is as such:
FQN.SRG(SIGNATURE)=EXCEPTIONS|PARAMETER NAMES[-ACCESS=<ACCESS>]
eg.
net/minecraft/client/Minecraft.func_71384_a()V=org/lwjgl/LWJGLException,java/io/IOException|
net/minecraft/client/Minecraft$2.<init>(Lnet/minecraft/client/Minecraft;)V=|p_i47419_1_
net/minecraft/server/dedicated/DedicatedServer.func_71190_q()V-Access=PUBLIC
Modern versions of MCInjector uses three files - constructors.txt, exceptions.txt and access.txt to encode this information. However, the legacy versions we use requires no changes.
Constructors.txt lines are in the format:
SRG_ID FQN SIGNATURE
Where the SRG_ID is the number preceding the second _ character in the EXC Line:
For example, the example line
net/minecraft/client/Minecraft$2.<init>(Lnet/minecraft/client/Minecraft;)V=|p_i47419_1_
will have the constructors.txt line
47419 net/minecraft/client/Minecraft$2 <init>(Lnet/minecraft/client/Minecraft;)V
Exceptions.txt lines are in the format:
CLASS/FUNCTION (PARAMS)RETURN ( EXCEPTION)+
For example, the example line
net/minecraft/client/Minecraft.func_71384_a()V=org/lwjgl/LWJGLException,java/io/IOException|
will have the exceptions.txt line
net/minecraft/client/Minecraft/func_71384_a ()V org/lwjgl/LWJGLException java/io/IOException
Access.txt lines are in the format:
ACCESS CLASS OBJECT SIGNATURE
For example, the example line
net/minecraft/server/dedicated/DedicatedServer.func_71190_q()V-Access=PUBLIC
will have the access.txt line
PUBLIC net/minecraft/server/dedicated/DedicatedServer func_71190 ()V
The MCP data contains a file called "joined.srg". The MCPConfig data expects a file called "joined.tsrg".
These formats were designed for intercompatibility, and thus they can be converted easily.
The existing method involves a python script based on this file.
dump_tsrg(srg_to_tsrg(file_in), file_out)
This script must be updated to use Java.
The MCP data contains a directory structure similar to:
│ Start.java
│
├───inject
│ │ package-info-template.java
│ │
│ └───common
│ └───mcp
│ MethodsReturnNonnullByDefault.java
MCPConfig expects this tree in the form:
├───inject
│ │ package-info-template.java
│ │
│ └───mcp
│ │ MethodsReturnNonnullByDefault.java
│ │
│ └───client
│ Start.java
The configuration file is where all of these steps are accumulated.
It defines the steps that ForgeGradle should take to apply our configuration, and the order.
For example, the 1.12.2 config.json:
{
"mcinjector": {
"version": "de.oceanlabs.mcp:mcinjector:3.7.3:fatjar",
"args": ["--in", "{input}", "--out", "{output}", "--log", "{log}", "--lvt=LVT", "--exc", "{exceptions}", "--acc", "{access}", "--ctr", "{constructors}"]
},
"fernflower": {
"version": "net.minecraftforge:forgeflower:1.0.342.8",
"args": ["-din=1", "-rbr=1", "-dgs=1", "-asc=1", "-rsy=1", "-iec=1", "-jvn=1", "-log=TRACE", "-cfg", "{libraries}", "{input}", "{output}"],
"jvmargs": ["-Xmx4G"]
},
"merge": {
"version": "net.minecraftforge:mergetool:0.2.3.2:fatjar",
"args": ["--client", "{client}", "--server", "{server}", "--ann", "{version}", "--output", "{output}"],
"jvmargs": []
},
"rename": {
"version": "net.md-5:SpecialSource:1.8.3:shaded",
"args": ["--in-jar", "{input}", "--out-jar", "{output}", "--srg-in", "{mappings}", "--kill-source"],
"repo": "https://repo1.maven.org/maven2/"
},
"libraries": {
"client": ["com.google.code.findbugs:jsr305:3.0.1"],
"server": ["com.google.code.findbugs:jsr305:3.0.1"],
"joined": ["com.google.code.findbugs:jsr305:3.0.1", "net.minecraftforge:mergetool:0.2.3.2:forge"]
}
}It defines the steps mcinjector, fernflower, merge and rename along with the programs that should be retrieved and how to run them.
MCInjector and ForgeFlower must be changed here.
mergetool MUST be removed from the libraries, lest the game crash at runtime due to the presence of a third Side; BUKKIT.