代码记录1

Posted 2022-05-03 guochaoxxl

record_def.s

 1 .equ RECORD_FIRSTNAME, 0                    #记录数据：firstName：40字节 0～39                                                             
  2 .equ RECORD_LASTNAME, 40                    #记录数据：lastName：40字节 40～79
  3 .equ RECORD_ADDRESS, 80                     #记录数据：address：240字节 80～319
  4 .equ RECORD_AGE, 320                        #记录数据：age：4字节 320～323
  5 .equ RECORD_SIZE, 324                       #记录数据：size：324字节 0～323

 

linuxg.s

  1 #文件名称：linuxg。s
  2 
  3 #系统调用中断号：
  4 .equ SYS_EXIT, 1 
  5 .equ SYS_READ, 3
  6 .equ SYS_WRITE, 4
  7 .equ SYS_OPEN, 5
  8 .equ SYS_CLOSE, 6
  9 .equ SYS_BRK, 45
 10 
 11 #调用Linux中断号：
 12 .equ LINUX_SYSCALL, 0x80
 13 
 14 #标准文件描述符号                                                         
 15 .equ STDIN, 0
 16 .equ STDOUT, 1
 17 .equ STDERR, 2
 18 
 19 .equ END_OF_FILE, 0  

 

read_record.s

  1 .include "record_def.s"
  2 .include "linuxg.s"
  3 
  4 .equ ST_READ_BUFFER, 8
  5 .equ ST_FILEDES, 12
  6 .section .text
  7 .globl read_record
  8 .type read_record, @function
  9 read_record:
 10     pushl %ebp
 11     movl %esp, %ebp
 12      
 13     pushl %ebx
 14     movl ST_FILEDES(%ebp), %ebx
 15     movl ST_READ_BUFFER(%ebp), %ecx
 16     movl $RECORD_SIZE, %edx
 17     movl $SYS_READ, %eax
 18     int $LINUX_SYSCALL
 19 
 20     popl %ebx
 21 
 22     movl %ebp, %esp
 23     popl %ebp
 24     ret  

write_record.s

  1 .include "record_def.s"
  2 .include "linuxg.s"
  3 
  4 .equ ST_WRITE_BUFFER, 8
  5 .equ ST_FILEDES, 12
  6 .section .text
  7 .globl write_record
  8 .type write_record, @function
  9 write_record:
 10     pushl %ebp
 11     movl %esp, %ebp
 12      
 13     pushl %ebx
 14     movl $SYS_WRITE, %eax
 15     movl ST_FILEDES(%ebp), %ebx
 16     movl ST_WRITE_BUFFER(%ebp), %ecx
 17     movl $RECORD_SIZE, %edx
 18     int $LINUX_SYSCALL
 19 
 20     popl %ebx                                                                                                                              
 21 
 22     movl %ebp, %esp
 23     popl %ebp
 24     ret

write_records.s

1 .include "linuxg.s"                                                                                                                                                                                                                                                                                                   
  2 .include "record_def.s"
  3 
  4 .section .data
  5 
  6 record1:
  7     .ascii "Fredrick\0"
  8     .rept 31                                                #填充到40字节
  9     .byte 0
 10     .endr
 11 
 12     .ascii "Bartlett\0"
 13     .rept 31
 14     .byte 0
 15     .endr
 16 
 17     .ascii "4242 S Prairie\nTulsa, OK 55555\0"
 18     .rept 209                                               #填充到240字节
 19     .byte 0
 20     .endr
 21 
 22     .long 45
 23 
 24 record2:
 25     .ascii "Marilyn\0"
 26     .rept 32                                                #填充到40字节
 27     .byte 0
 28     .endr
 29 
 30     .ascii "Taylor\0"
 31     .rept 33
 32     .byte 0
 33     .endr
 34 
 35     .ascii "2224 S Johannan St\nChicago, IL 12345\0"
 36     .rept 203                                               #填充到240字节
 37     .byte 0
 38     .endr
 39 
 40     .long 29
 41 
 42 record3:
 43     .ascii "Derrick\0"
 44     .rept 32                                                #填充到40字节
 45     .byte 0
 46     .endr
 47 
 48     .ascii "McIntire\0"
 49     .rept 31
 50     .byte 0
 51     .endr
 52 
 53     .ascii "500 W Oakland\nSan Diego, CA 54321\0"
 54     .rept 206                                               #填充到240字节
 55     .byte 0
 56     .endr
 57 
 58     .long 36
 59 
 60     fileName:                                               #书上代码错误，另外添加
 61     .ascii "test.dat\0"
 62     .equ ST_FILE_DESCRIPTOR, -4
 63     .globl _start
 64 _start:
 65     movl %esp, %ebp
 66     subl $4, %esp
 67 
 68 #打开文件
 69     movl $SYS_OPEN, %eax
 70     movl $fileName, %ebx
 71     movl $0101, %ecx
 72     movl $0666, %edx
 73     int $LINUX_SYSCALL
 74 
 75     movl %eax, ST_FILE_DESCRIPTOR(%ebp)
 76     
 77 #写入第一条记录
 78     pushl ST_FILE_DESCRIPTOR(%ebp)
 79     pushl $record1
 80     call write_record
 81     addl $8, %esp
 82 
 83 #写入第二条记录
 84     pushl ST_FILE_DESCRIPTOR(%ebp)
 85     pushl $record2
 86     call write_record
 87     addl $8, %esp
 88 
 89 #写入第三条记录
 90     pushl ST_FILE_DESCRIPTOR(%ebp)
 91     pushl $record3
 92     call write_record
 93     addl $8, %esp
 94 
 95 #关闭文件
 96     movl $SYS_CLOSE, %eax
 97     movl ST_FILE_DESCRIPTOR(%ebp), %ebx
 98     int $LINUX_SYSCALL
 99 
100 #退出文件
101     movl $SYS_EXIT, %eax
102     movl $0, %ebx
103     int $LINUX_SYSCALL