annotate Python/memmove.c @ 31606:fd2103ae6f29 legacy-trunk

Add pystack definition to Misc/gdbinit with some explanation of its behavior and add flag comments to ceval.c and main.c alerting people to the coupling between pystack and the layout of those files.
author Skip Montanaro <skip@pobox.com>
date Mon, 01 Mar 2004 15:44:05 +0000
parents 6f6f965c5e2d
children
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1
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2 /* A perhaps slow but I hope correct implementation of memmove */
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3
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4 extern char *memcpy(char *, char *, int);
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6 char *
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7 memmove(char *dst, char *src, int n)
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8 {
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9 char *realdst = dst;
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10 if (n <= 0)
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11 return dst;
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12 if (src >= dst+n || dst >= src+n)
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13 return memcpy(dst, src, n);
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14 if (src > dst) {
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15 while (--n >= 0)
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16 *dst++ = *src++;
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17 }
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18 else if (src < dst) {
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19 src += n;
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20 dst += n;
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21 while (--n >= 0)
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22 *--dst = *--src;
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23 }
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24 return realdst;
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25 }