zig/std/bootstrap.zig
2016-01-16 00:07:34 -07:00

37 lines
864 B
Zig

import "syscall.zig";
// The compiler treats this file special by implicitly importing the function `main`
// from the root source file.
var argc: usize;
var argv: &&u8;
var env: &&u8;
#attribute("naked")
export fn _start() unreachable => {
argc = asm("mov (%%rsp), %[argc]": [argc] "=r" (-> usize));
argv = asm("lea 0x8(%%rsp), %[argv]": [argv] "=r" (-> &&u8));
env = asm("lea 0x10(%%rsp,%%rdi,8), %[env]": [env] "=r" (-> &&u8));
call_main()
}
fn strlen(ptr: &u8) usize => {
var count: usize = 0;
while (ptr[count] != 0) {
count += 1;
}
return count;
}
fn call_main() unreachable => {
var args: [argc][]u8;
var i : @typeof(argc) = 0;
// TODO for in loop over the array
while (i < argc) {
const ptr = argv[i];
args[i] = ptr[0...strlen(ptr)];
i += 1;
}
exit(main(args))
}