Skip to content
Permalink
Browse files

Document how to compile plugins on linux

  • Loading branch information...
UnknownShadow200 committed May 13, 2019
1 parent 22e3252 commit 63ab591b699ba7355394d25b3a1ccdbf87ac6ae8
Showing with 106 additions and 0 deletions.
  1. +106 −0 misc/plugin-dev.md
@@ -0,0 +1,106 @@
This document details how to compile a basic plugin in Visual Studio, MinGW, or GCC.

To find the functions and variables available for use in plugins, look for CC_API/CC_VAR in the .h files.

[Source code of some actual plugins](https://github.com/UnknownShadow200/ClassiCube-Plugins/tree/master/src)

### Setup

You need to download and install either Visual Studio, MinGW, or GCC.

*Note: MinGW/GCC are relatively small, while Visual Studio is gigabytes in size.
If you're just trying to compile a plugin on Windows you might want to use MinGW. See main readme.*

I assume your directory is structured like this:
```
src/...
TestPlugin.c
```
Or in other words, in a directory somewhere, you have a file named ```TestPlugin.c```, and then a sub-directory named ```src``` which contains the game's source code.

### Basic plugin
```C
#include "src/Chat.h"
#include "src/GameStructs.h"
static void TestPlugin_Init(void) {
String msg = String_FromConst("Hello world!");
Chat_Add(&msg);
}
int Plugin_ApiVersion = 1;
struct IGameComponent Plugin_Component = { TestPlugin_Init };
```
Here's the idea for a basic plugin that shows "Hello world" in chat when the game starts. Alas, this won't compile...

### Basic plugin boilerplate
```C
#include "src/Chat.h"
#include "src/GameStructs.h"
#ifdef CC_BUILD_WIN
#define CC_API __declspec(dllimport)
#define CC_VAR __declspec(dllimport)
#define EXPORT __declspec(dllexport)
#else
#define CC_API
#define CC_VAR
#define EXPORT __attribute__((visibility("default")))
#endif
static void TestPlugin_Init(void) {
String msg = String_FromConst("Hello world!");
Chat_Add(&msg);
}
EXPORT int Plugin_ApiVersion = 1;
EXPORT struct IGameComponent Plugin_Component = { TestPlugin_Init };
```
With this boilerplate, we're ready to compile the plugin.
All plugins require this boilerplate, so feel free to copy and paste it.

---

### Linux
#### For Linux
**Compiling**

```gcc TestPlugin.c -o TestPlugin.so -shared -fPIC```
Then put ```TestPlugin.so``` into your game's ```plugins``` folder. Done.
#### Cross compile for Windows 32 bit
**Prerequisites:**
1) Compile the game, see ```Cross compiling for windows``` in main readme
2) Rename compiled executable to ClassiCube.exe
3) Install the ```mingw-w64-tools``` package
**Compiling**
First, generate list of exported symbols:
```gendef src/ClassiCube.exe```
Next create a linkable library:
```i686-w64-mingw32-dlltool -d ClassiCube.def -l libClassiCube.a -D ClassiCube.exe```
Finally compile the plugin:
```i686-w64-mingw32-gcc TestPlugin.c -o TestPlugin.dll -s -shared -L . -lClassiCube```
Then put ```TestPlugin.dll``` into your game's ```plugins``` folder. Done.
##### Ultra small dlls
If you **ONLY** use code from the game (no external libraries and no C standard library functions), add ```-nostartfiles -Wl,--entry=0``` to the compile flags
This step isn't necessary, the dll works fine without it. But it does reduce the size of the dll from 11 to 4 kb.
#### Cross compile for Windows 64 bit
Repeat the steps of *Cross compile for Windows 32 bit*, but use ```x86_64-w64-mingw32``` instead of ```i686-w64-mingw32```
### Windows
TODO when I have some more time...

0 comments on commit 63ab591

Please sign in to comment.
You can’t perform that action at this time.