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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 | +} | |