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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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