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#include "byte.h"
/**
* @file byte.c
* @author djb
* @brief byte manipulation functions
*/
unsigned int byte_chr(char *s,unsigned int n,int c)
{
char ch = c;
char *t = s;
for (;;) {
if (!n) { break; } if (*t == ch) { break; } ++t; --n;
}
return t - s;
}
void byte_copy(void *to,unsigned int n,const void *from)
{
char *out = to; // share same address
const char *in = from; // one byte
for (;;) {
if (!n) { return; } *out++ = *in++; --n;
}
}
void byte_copyr(void *to,unsigned int n,const void *from)
{
char *out = to + n;
const char *in = from + n;
for (;;) {
if (!n) { return; } *--out = *--in; --n;
}
}
int byte_diff(const void *s,unsigned int n,const void *t)
{
const char *a = s;
const char *b = t;
for (;;) {
if (!n) { return 0; } if (*a != *b) { break; } ++a; ++b; --n;
}
return ((int)(unsigned int)(unsigned char) *a)
- ((int)(unsigned int)(unsigned char) *b);
}
unsigned int byte_rchr(char *s,unsigned int n,int c)
{
char ch = c;
char *t = s;
char *u = 0;
for (;;) {
if (!n) { break; } if (*t == ch) { u = t; } ++t; --n;
}
if (!u) { u = t; }
return u - s;
}
void byte_zero(void *s,unsigned int n)
{
char *out = s;
for (;;) {
if (!n) { break; } *out++ = 0; --n;
}
}
void byte_fill(void *to,unsigned int n,int c)
{
char *s = to;
char ch = c;
for (;;) {
if (!n) { break; } *s++ = ch; --n;
}
}
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