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#ifndef lint |
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static const char RCSid[] = "$Id$"; |
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#endif |
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/* |
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* String in string (limited search length) |
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*/ |
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|
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#include "copyright.h" |
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#include "rtio.h" |
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|
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char * |
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strnstr(const char *haystack, const char *needle, size_t len) |
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{ |
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const size_t nlen = strlen(needle); |
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const char *spos = haystack; |
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int i; |
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|
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if (!nlen) { /* special case */ |
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while (len--) { |
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if (!*spos) |
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return((char *)spos); |
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++spos; |
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} |
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return(NULL); /* haystack is longer than len */ |
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} |
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if (len < nlen) /* not long enough for match! */ |
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return(NULL); |
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len -= nlen; |
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do { |
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for (i = 0; i < nlen; i++) |
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if (spos[i] != needle[i]) |
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break; |
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|
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if (i == nlen) /* found match? */ |
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return((char *)spos); |
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|
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} while (((spos++)[i] != '\0') & (len-- != 0)); |
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|
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return(NULL); /* no match found */ |
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} |
