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| 1 | |||
| 2 | /* A perhaps slow but I hope correct implementation of memmove */ | ||
| 3 | |||
| 4 | extern char *memcpy(char *, char *, int); | ||
| 5 | |||
| 6 | char * | ||
| 7 | memmove(char *dst, char *src, int n) | ||
| 8 | { | ||
| 9 | char *realdst = dst; | ||
| 10 | if (n <= 0) | ||
| 11 | return dst; | ||
| 12 | if (src >= dst+n || dst >= src+n) | ||
| 13 | return memcpy(dst, src, n); | ||
| 14 | if (src > dst) { | ||
| 15 | while (--n >= 0) | ||
| 16 | *dst++ = *src++; | ||
| 17 | } | ||
| 18 | else if (src < dst) { | ||
| 19 | src += n; | ||
| 20 | dst += n; | ||
| 21 | while (--n >= 0) | ||
| 22 | *--dst = *--src; | ||
| 23 | } | ||
| 24 | return realdst; | ||
| 25 | } | ||