1                                 %line 1+1 screen.msg.asm
     2                                 
     3                                 
     4                                 
     5                                 
     6                                 
     7                                 
     8                                 
     9                                 
    10                                 
    11                                 
    12                                 [global printString]
    13                                 printString:
    14 00000000 53                     push rbx
    15                                 
    16                                 
    17 00000001 4889FB                 mov rbx, rdi
    18 00000004 48C7C200000000         mov rdx, 0
    19                                 
    20                                 strCountLoop:
    21 0000000B 803B00                 cmp byte [rbx], NULL
    22 0000000E 7406                   je strCountDone
    23 00000010 48FFC2                 inc rdx
    24 00000013 48FFC3                 inc rbx
    25 00000016 EBF1                   jmp strCountLoop
    26                                 
    27                                 strCountDone:
    28 00000018 4883FA00               cmp rdx, 0
    29 0000001C 7411                   je prtDone
    30                                 
    31                                 
    32                                 
    33 0000001E 48C7C001000000         mov rax, SYS_write
    34 00000025 4889FE                 mov rsi, rdi
    35 00000028 48C7C701000000         mov rdi, STDOUT
    36                                 
    37 0000002F 0F05                   syscall
    38                                 
    39                                 
    40                                 prtDone:
    41 00000031 5B                     pop rbx
    42 00000032 C3                     ret
    43                                 
    44                                 
    45                                 
    46                                 
    47                                 
    48                                 [section .data]
    49                                 LF equ 10
    50                                 NULL equ 0
    51                                 TRUE equ 1
    52                                 FALSE equ 0
    53                                 EXIT_SUCCESS equ 0
    54                                 STDIN equ 0
    55                                 STDOUT equ 1
    56                                 STDERR equ 2
    57                                 SYS_read equ 0
    58                                 SYS_write equ 1
    59                                 SYS_open equ 2
    60                                 SYS_close equ 3
    61                                 SYS_fork equ 57
    62                                 SYS_exit equ 60
    63                                 SYS_creat equ 85
    64                                 SYS_time equ 201
    65                                 
    66                                 
    67                                 STRLEN equ 50
    68 00000000 656E74657220746578-    prmpt db "enter text: ", NULL
    69 00000000 743A2000           
    70 0000000D 0A00                   new_line db LF, NULL
    71                                 
    72                                 [section .bss]
    73 00000000 <gap>                  _char resb 1
    74 00000001 <gap>                  in_line resb STRLEN+2
    75                                 
    76                                 [section .text]
    77                                 [global _start]
    78                                 _start:
    79                                 
    80 00000033 48C7C7[00000000]       mov rdi, prmpt
    81 0000003A E8BCFFFFFF             call printString
    82                                 
    83                                 
    84 0000003F 48C7C3[00000000]       mov rbx, in_line
    85 00000046 49C7C400000000         mov r12, 0
    86                                 read_Characters:
    87 0000004D 48C7C000000000         mov rax, SYS_read
    88 00000054 48C7C700000000         mov rdi, STDIN
    89 0000005B 488D3425[00000000]     lea rsi, byte [_char]
    90 00000063 48C7C201000000         mov rdx, 1
    91 0000006A 0F05                   syscall
    92 0000006C 8A0425[00000000]       mov al, byte [_char]
    93 00000073 3C0A                   cmp al, LF
    94 00000075 740E                   je readDone
    95 00000077 49FFC4                 inc r12
    96 0000007A 4983FC32               cmp r12, STRLEN
    97 0000007E 73CB                   jae read_Characters
    98 00000080 8803                   mov byte [rbx], al
    99 00000082 48FFC3                 inc rbx
   100 00000085 EBC4                   jmp read_Characters
   101                                 readDone:
   102 00000087 C60300                 mov byte [rbx], NULL
   103                                 
   104                                 
   105 0000008A 48C7C7[00000000]       mov rdi, in_line
   106 00000091 E865FFFFFF             call printString
   107                                 
   108 00000096 48C7C03C000000         mov rax, SYS_exit
   109 0000009D 48C7C700000000         mov rdi, EXIT_SUCCESS
   110 000000A4 0F05                   syscall