25 lines
811 B
Zig
25 lines
811 B
Zig
fn syscall3(number: isize, arg1: isize, arg2: isize, arg3: isize) -> isize {
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let mut result : isize;
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asm volatile ("
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mov %[number], %%rax
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mov %[arg1], %%rdi
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mov %[arg2], %%rsi
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mov %[arg3], %%rdx
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syscall
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mov %%rax, %[ret]"
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: [ret] "=m" (result)
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: [number] "r" (number), [arg1] "r" (arg1), [arg2] "r" (arg2), [arg3] "r" (arg3)
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: "rcx", "r11", "rax", "rdi", "rsi", "rdx");
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return result;
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}
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// TODO error handling
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// TODO zig strings instead of C strings
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// TODO handle buffering and flushing
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// TODO non-i32 integer literals so we can remove the casts
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pub fn print_str(str : *const u8, len: isize) {
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let SYS_write = 1;
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let stdout_fileno = 1;
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syscall3(SYS_write as isize, stdout_fileno as isize, str as isize, len);
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}
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