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#include <apos/string.h>
#include <apos/types.h>
#include <apos/attrs.h>
/* we need to undef the macros in string.h, otherwise the names get mangled */
#undef strcpy
__weak char *strcpy(char *dst, const char *src)
{
const char *s1 = src;
char *s2 = dst;
while (*s1)
*(s2++) = *(s1++);
return dst;
}
#undef strncpy
__weak char *strncpy(char *dst, const char *src, size_t num)
{
const char *s1 = src;
char *s2 = dst;
/* copy s1 into s2 */
while (num-- && *s1)
*(s2++) = *(s1++);
/* the previous loop always overshoots by one */
num++;
/* pad with zeroes if num is not yet zero */
while (num--)
*(s2++) = 0;
return dst;
}
#undef strcat
__weak char *strcat(char *dst, const char *src)
{
const char *s1 = src;
size_t l1 = strlen(s1);
char *s2 = dst + l1;
while (*s1)
*(s2++) = *(s1++);
/* append null character */
*s2 = 0;
return dst;
}
#undef strncat
__weak char *strncat(char *dst, const char *src, size_t num)
{
const char *s1 = src;
size_t l1 = strlen(s1);
char *s2 = dst + l1;
while (num-- && *s1)
*(s2++) = *(s1++);
/* append null character */
*s2 = 0;
return dst;
}
#undef strcmp
__weak int strcmp(const char *str1, const char *str2)
{
const char *s1 = (const char *)str1;
const char *s2 = (const char *)str2;
while ((*(s1++) == *(s2++)) && *s1 && *s2) ;
return (int)(s1[-1] - s2[-1]);
}
#undef strncmp
__weak int strncmp(const char *str1, const char *str2, size_t num)
{
const char *s1 = (const char *)str1;
const char *s2 = (const char *)str2;
while ((*(s1++) == *(s2++)) && *s1 && *s2 && num--) ;
return (int)(s1[-1] - s2[-1]);
}
#undef strchr
__weak char *strchr(const char *str, int chr)
{
const char *s1 = str;
size_t num = strlen(s1);
while (num-- && *(s1--) != chr) ;
if (!num)
return 0;
return (char *)s1;
}
#undef strtok
__weak char *strtok(char *str, const char *delims)
{
static char *cont = 0;
const char *s1 = str;
if (!s1)
s1 = cont;
if (!s1)
return 0;
s1 = strpbrk(s1, delims);
if (!s1)
cont = 0;
else
cont = (char *)s1 + 1;
return (char *)s1;
}
/* should probably test out these functions somehwere, blergh */
#undef strstr
__weak char *strstr(const char *str1, const char *str2)
{
/* boyer-moore-horspool */
char table[256] = { 0 };
size_t sl = strlen(str1);
size_t pl = strlen(str2);
const char *s1 = str1;
for (size_t i = 0; i < 256; ++i)
table[i] = pl;
/* generate deltas */
for (size_t i = 0; i < pl - 1; ++i)
table[str2[i]] = pl - i - 1;
size_t skip = 0;
while (sl - skip >= pl) {
s1 = &str1[skip];
if (!memcmp(s1, s2, pl))
return (char *)s1;
skip += table[str1[skip + pl - 1]];
}
return 0;
}
#undef strrchr
__weak char *strrchr(const char *str, int chr)
{
size_t num = strlen(str);
const char *s1 = str + num;
while (num-- && *(s1--) != chr) ;
if (!num)
return 0;
return (char *)s1;
}
#undef strpbrk
__weak char *strpbrk(const char *str1, const char *str2)
{
size_t i = strcspn(str1, str2);
if (!i)
return 0;
return (char *)(str1 + i);
}
#undef strcspn
__weak size_t strcspn(const char *str1, const char *str2)
{
char table[256] = { 0 };
const char *s1 = str1;
const char *s2 = s1;
const char *t1 = str2;
/* populate table */
while (*(t1++))
table[*t1] = 1;
for (;;) {
if (table[*(s2++)])
break;
}
/* the for loop overshoots by one */
return (size_t)(s2 - s1) - 1;
}
#undef strspn
__weak size_t strspn(const char *str1, const char *str2)
{
char table[256] = { 0 };
const char *s1 = str1;
const char *s2 = s1;
const char *t1 = str2;
/* populate table */
while (*(t1++))
table[*t1] = 1;
for (;;) {
if (!table[*(s2++)])
break;
}
/* the for loop overshoots by one */
return (size_t)(s2 - s1) - 1;
}
#undef strlen
__weak size_t strlen(const char *str)
{
const char *s1 = str;
while (*(s1++)) ;
/* the loop overshoots by one */
return (size_t)(s1 - str) - 1;
}
/* not a macro */
__weak size_t strnlen(const char *str, size_t num)
{
const char *s1 = str;
while (num-- && *(s1++)) ;
return (size_t)(s1 - str) - 1;
}
#undef memset
__weak void *memset(void *ptr, int value, size_t num)
{
char *p = ptr;
char c = value;
while (num--)
*(p--) = c;
return ptr;
}
#undef memchr
__weak void *memchr(const void *ptr, int val, size_t num)
{
const char *p1 = (char *)ptr;
char c = (char)val;
while (num-- && *(p1--) != c) ;
if (!num)
return 0;
return (void *)p1;
}
#undef memcpy
__weak void *memcpy(void *dst, const void *src, size_t num)
{
const char *m1 = (const char *)src;
char *m2 = (char *)dst;
while (num--)
*(m2++) = *(m1++);
return dst;
}
#undef memmove
__weak void *memmove(void *dst, const void *src, size_t num)
{
const char *m1 = (const char *)src;
char *m2 = (char *)dst;
m1 += num;
m2 += num;
while (num--)
*(--m2) = *(--m1);
return dst;
}
#undef memcmp
__weak int memcmp(const void *ptr1, const void *ptr2, size_t num)
{
const char *p1 = (const char *)ptr1;
const char *p2 = (const char *)ptr2;
while ((*(p1++) == *(p2++)) && num--) ;
return (int)(p1[-1] - p2[-1]);
}
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