# Must be included at the top of the file
asm "extern malloc, realloc, free, printf, open, close, read, write"

{}uint8 _alert = "Alert!\n\0"
{}uint8 _dec = "%d\n\0"
{}uint8 _ptr = "%p\n\0"

/; _alloc (uint size) [~void]
    ~void out

    asm "mov rax, rsp"
    asm "xor rdx, rdx"
    asm "mov rcx, 16"
    asm "div rcx"
    asm "sub rsp, rdx"
    asm "sub rsp, 128"
    
    # Mov size into proper register, and set all extras to zero
    asm "mov rdi, r10"
    asm "mov rsi, 0"
    asm "xor rax, rax"
    
    # Do call
    asm "call malloc wrt ..plt"

    # Set out to the returned value
    # (The compiler assignes spaces sequentially, and we have a uint in r10)
    asm "mov r11, rax"

    return out
;/

/; _realloc (~void ptr, uint new_size) [~void]
    ~void out

    asm "mov rax, rsp"
    asm "xor rdx, rdx"
    asm "mov rcx, 16"
    asm "div rcx"
    asm "sub rsp, rdx"
    asm "sub rsp, 128"
    
    # Mov ptr and new size into proper registers, and set all extras to zero
    asm "mov rdi, r10"
    asm "mov rsi, r11"
    asm "xor rax, rax"

    # Do call
    asm "call realloc wrt ..plt"
    
    # Set out to the returned value
    # (The compiler assignes spaces sequentially. We have a ptr in r10, and a uint in r11)
    asm "mov r12, rax"

    return out
;/

/; _delete (~void ptr)

    asm "mov rax, rsp"
    asm "xor rdx, rdx"
    asm "mov rcx, 16"
    asm "div rcx"
    asm "sub rsp, rdx"
    asm "sub rsp, 128"
    
    # setup call by clearing most values
    asm "mov rdi, r10"
    asm "mov rsi, 0"
    asm "xor rax, rax"

    # do call
    asm "call free wrt ..plt"

    # there's no more to do 'cause free returns nothing 
;/

/; _printf (~void str)

    asm "mov rax, rsp"
    asm "xor rdx, rdx"
    asm "mov rcx, 16"
    asm "div rcx"
    asm "sub rsp, rdx"
    asm "sub rsp, 128"
    
    # setup call by clearing most values
    asm "mov rdi, r10"
    asm "xor rsi, rsi"
    asm "xor rax, rax"
    
    # do call
    asm "call printf wrt ..plt"
    
    # there's no more to do 'cause printf returns nothing 
;/

/; _print_num (~void str, int num)

    asm "mov rax, rsp"
    asm "xor rdx, rdx"
    asm "mov rcx, 16"
    asm "div rcx"
    asm "sub rsp, rdx"
    asm "sub rsp, 128"
    
    # setup call by clearing most values
    asm "mov rdi, r10"
    asm "mov rsi, r11"
    asm "xor rax, rax"
    
    # do call
    asm "call printf wrt ..plt"
    
    # there's no more to do 'cause printf returns nothing 
;/


# Create file for writing (overwrite)
/; _create_file (~void name) [~void]
    ~void out

    asm "mov rax, rsp"
    asm "xor rdx, rdx"
    asm "mov rcx, 16"
    asm "div rcx"
    asm "sub rsp, rdx"
    asm "sub rsp, 128"

    # Do call
    asm "mov rdi, r10"
    asm "mov rsi, 0q1102"
    asm "mov rdx, 0q700"
    asm "call open wrt ..plt"

    # Set out to the returned value
    # (The compiler assignes spaces sequentially. We have a ptr in r8)
    asm "mov r11, rax"

    return out
;/

# Open file for reading or writing (no overwrite)
/; _open_file (~void name) [~void]
    ~void out

    asm "mov rax, rsp"
    asm "xor rdx, rdx"
    asm "mov rcx, 16"
    asm "div rcx"
    asm "sub rsp, rdx"
    asm "sub rsp, 128"

    # Do syscall
    asm "mov rdi, r10"
    asm "mov rsi, 2"
    asm "mov rdx, 0q700"
    asm "call open wrt ..plt"

    # Set out to the returned value
    # (The compiler assignes spaces sequentially. We have a ptr in r8, and a uint in r9)
    asm "mov r11, rax"

    return out
;/

/; _close_file (~void handle)

    asm "mov rax, rsp"
    asm "xor rdx, rdx"
    asm "mov rcx, 16"
    asm "div rcx"
    asm "sub rsp, rdx"
    asm "sub rsp, 128"

    # Do syscall
    asm "mov rdi, r10"
    asm "call close wrt ..plt"
;/

/; _read_byte (~void handle, ~uint8 byte) [int]
    int out

    asm "mov rax, rsp"
    asm "xor rdx, rdx"
    asm "mov rcx, 16"
    asm "div rcx"
    asm "sub rsp, rdx"
    asm "sub rsp, 128"

    # Do syscall
    asm "mov rdi, r10"  # handle
    asm "mov rsi, r11"  # buffer
    asm "mov rdx, 1"   # one byte
    asm "call read wrt ..plt"

    # return number of bytes read
    asm "mov r12, rax"

    return out
;/

/; _write_byte (~void handle, ~uint8 byte) [int]
    int out

    asm "mov rax, rsp"
    asm "xor rdx, rdx"
    asm "mov rcx, 16"
    asm "div rcx"
    asm "sub rsp, rdx"
    asm "sub rsp, 128"

    # Do syscall
    asm "mov rdi, r10"  # handle
    asm "mov rsi, r11"  # buffer
    asm "mov rdx, 1"   # one byte
    asm "call write wrt ..plt"

    asm "mov r12, rax"

    return out
;/

/; print_alert
    _printf(~_alert{0})
;/