1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
|
# uefi.c3l - UEFI Definitions & Library for C3
A gnu-efi-like library enabling UEFI bootloader development in C3.
## Installation
The library is incredibly easy to pull and use right away.
1. Change to your project's `lib` directory.
2. Clone this repository: `git clone https://github.com/NotsoanoNimus/uefi.c3l.git`.
3. Start developing with `import uefi;` where needed.
Most c3c projects will automatically source modules from their `lib` folders. If this is not the case, you can use the following `c3c` parameters to source the library: `--lib uefi --libdir lib/`
This will certainly be improved as the project becomes more mature.
## Compiling EFI Binaries
I need to revisit this, but I have been successfully compiling my EFI test binaries with the following:
```
~$ c3c compile-only src/*.c3 --link-libc=no --no-entry \
--target windows-x64 --lib uefi --libdir ./lib
~$ clang -target x86_64-unknown-windows -nostdlib -fno-stack-protector -mno-red-zone \
-ffreestanding -fPIC -Wl,-entry:efi_main -Wl,-subsystem:efi_application \
-fuse-ld=lld-link -mno-stack-arg-probe -v -o test.efi ./obj/windows-x64/*.obj
```
I'm pretty sure I'm switching up my compilation and linker arguments for this right now. :shrug: Again, to be improved as the project matures.
This snippet explicitly uses `clang` and `lld-link` in order to generate the EFI application. For me, it's a must; however, others may be more comfortable linking with another tool like `gcc`. It's all the same after `c3c` generates its objects.
## Example Usage
The following example shows what a "Hello World" style EFI application might look like in C3. When it starts, it sets a baseline console color, clears the window, and attempts to enable the Graphics Output Protocol and draw a simple rectangle.
Some of these methods currently don't exist; this is more of a "finished product" presentation.
```cpp
module hello_uefi;
import uefi;
fn EfiStatus efi_main(EfiHandle image_handle, SystemTable* system_table) @export("efi_main")
{
pre_load::init(image_handle, system_table)!!;
console::clear_to({YELLOW, RED});
io::cprintn(@wstring("Enabling GOP mode..."), {GREEN, BLACK})!!;
if (catch excuse = sys::enable_gop()) {
io::cprintn(@wstring("ERROR: Failed to initialize Graphics Output Protocol."), {RED, BLACK})!!;
} else {
gop::draw_rect(
{0, 0, 100, 200},
{{0xff, 0x12, 0x34, 0x56}, {.a = 0xff, .r = 0xdd}} /* {r,g,b,a} */
);
}
sys::@stall(s2us(3)); /* s2us == sec-to-microsec */
sys::@reset(SHUTDOWN);
}
```
## TODOs
In no particular order...
- [ ] Finish C3 standard library integration, to provide helpful constructs like String formatting and such.
- [ ] Implement all macro exports for System, Console, etc.
- [ ] Organize library imports such that `uefi` isn't just bulk-imported everywhere.
- [ ] Unit/Integration testing.
- Not sure if this will require a mock UEFI environment, or if it will need to be on a function-by-function basis. We'll see.
- [ ] Graphics library support and support functions .
- [ ] e.g. an optional BLT-based framebuffer lib.
|
