1 #include "lib9.h" 2 3 char* 4 cistrstr(char *s, char *sub) 5 { 6 int c, csub, n; 7 8 csub = *sub; 9 if(csub == '\0') 10 return s; 11 if(csub >= 'A' && csub <= 'Z') 12 csub -= 'A' - 'a'; 13 sub++; 14 n = strlen(sub); 15 for(; c = *s; s++){ 16 if(c >= 'A' && c <= 'Z') 17 c -= 'A' - 'a'; 18 if(c == csub && cistrncmp(s+1, sub, n) == 0) 19 return s; 20 } 21 return nil; 22 } 23