diff options
Diffstat (limited to 'byte.c')
-rw-r--r-- | byte.c | 99 |
1 files changed, 99 insertions, 0 deletions
@@ -0,0 +1,99 @@ +#include "byte.h" + +/** + @file byte.c + @author djb + @brief byte manipulation functions +*/ + +unsigned int byte_chr(char *s,register unsigned int n,int c) +{ + register char ch; + register char *t; + + ch = c; + t = s; + for (;;) { + if (!n) { break; } if (*t == ch) { break; } ++t; --n; + if (!n) { break; } if (*t == ch) { break; } ++t; --n; + if (!n) { break; } if (*t == ch) { break; } ++t; --n; + if (!n) { break; } if (*t == ch) { break; } ++t; --n; + } + return t - s; +} + +void byte_copy(register char *to,register unsigned int n,register char *from) +{ + for (;;) { + if (!n) { return; } *to++ = *from++; --n; + if (!n) { return; } *to++ = *from++; --n; + if (!n) { return; } *to++ = *from++; --n; + if (!n) { return; } *to++ = *from++; --n; + } +} + +void byte_copyr(register char *to,register unsigned int n,register char *from) +{ + to += n; + from += n; + for (;;) { + if (!n) { return; } *--to = *--from; --n; + if (!n) { return; } *--to = *--from; --n; + if (!n) { return; } *--to = *--from; --n; + if (!n) { return; } *--to = *--from; --n; + } +} + +int byte_diff(register char *s,register unsigned int n,register char *t) +{ + for (;;) { + if (!n) { return 0; } if (*s != *t) { break; } ++s; ++t; --n; + if (!n) { return 0; } if (*s != *t) { break; } ++s; ++t; --n; + if (!n) { return 0; } if (*s != *t) { break; } ++s; ++t; --n; + if (!n) { return 0; } if (*s != *t) { break; } ++s; ++t; --n; + } + return ((int)(unsigned int)(unsigned char) *s) + - ((int)(unsigned int)(unsigned char) *t); +} + +unsigned int byte_rchr(char *s,register unsigned int n,int c) +{ + register char ch; + register char *t; + register char *u; + + ch = c; + t = s; + u = 0; + for (;;) { + if (!n) { break; } if (*t == ch) { u = t; } ++t; --n; + if (!n) { break; } if (*t == ch) { u = t; } ++t; --n; + if (!n) { break; } if (*t == ch) { u = t; } ++t; --n; + if (!n) { break; } if (*t == ch) { u = t; } ++t; --n; + } + if (!u) { u = t; } + return u - s; +} + +void byte_zero(char *s,register unsigned int n) +{ + for (;;) { + if (!n) { break; } *s++ = 0; --n; + if (!n) { break; } *s++ = 0; --n; + if (!n) { break; } *s++ = 0; --n; + if (!n) { break; } *s++ = 0; --n; + } +} + +void byte_fill(char *s,register unsigned int n,const int c) +{ + register char ch; + + ch = c; + for (;;) { + if (!n) { break; } *s++ = ch; --n; + if (!n) { break; } *s++ = ch; --n; + if (!n) { break; } *s++ = ch; --n; + if (!n) { break; } *s++ = ch; --n; + } +} |