安防之家讯:文件strtest.c
1 #include <stdio.h>
2 extern void strcopy(char *d, const char *s);
3 int main()
4 { const char *srcstr = "First string - source";
5 char dststr[] = "Second string - destination";
6
7
8 printf("Before copying:\n");
9 printf(" '%s'\n '%s'\n",srcstr,dststr);
10 strcopy(dststr,srcstr);
11 printf("After copying:\n");
12 printf(" '%s'\n '%s'\n",srcstr,dststr);
13 return 0;
14 }
文件scopy.s
1 AREA SCopy, CODE, READONLY
2 EXPORT strcopy
3 strcopy
4 ; r0 points to destination string
5 ; r1 points to source string
6 LDRB r2, [r1],#1 ; load byte and update address
7 STRB r2, [r0],#1 ; store byte and update address;
8 CMP r2, #0 ; check for zero terminator
9 BNE strcopy ; keep going if not
10 MOV pc,lr ; Return
11 END安防之家专注于各种家居的安防,监控,防盗,安防监控,安防器材,安防设备的新闻资讯和O2O电商导购服务,敬请登陆安防之家:http://anfang.jc68.com/