24 lines
756 B
Zig
24 lines
756 B
Zig
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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\n"
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"mov %[arg1], %%rdi\n"
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"mov %[arg2], %%rsi\n"
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"mov %[arg3], %%rdx\n"
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"syscall\n"
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"mov %%rax, %[ret]\n"
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: [ret] "=r" (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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pub 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, stdout_fileno, str as isize, str_len);
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}
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