一些简单C函数的源码

}
4.//**************************************************************************************
char * strchr (
const char * string,
int ch
int sign; /* if '-', then negative, otherwise positive */
/* skip whitespace */
while ( isspace((int)(unsigned char)*nptr) )
buf2 = (char *)buf2 + 1;
}
return( *((unsigned char *)buf1) - *((unsigned char *)buf2) );
}
10.//*************************************************************************************
c = (int)(unsigned char)*nptr++; /* get next char */
}
if (sign == '-')
return -total;
else
return total; /* return result, negated if necessary */
)
{
while (*string != '\0' && *string != ch)
string++;
return *string == ch ? string : (char*) 0;
}
5.//**************************************************************************************
link *q = head;
while(p != NULL && q != NULL && q->next != NULL)
{
p = p->next;
q = q->next->next;
if(p == q)
return true;
}
return false;
++nptr;
c = (int)(unsigned char)*nptr++;
sign = c; /* save sign indication */
if (c == '-' || c == '+')
char *strstr (char *buf,char *sub)
{
char *bp;
char *sp;
if (!*sub)
return buf;
while (*buf)
{
bp = buf;
sp = sub;
while (*bp++ == *sp++)
size_t count
)
{
if (!count)
return(0);
while ( --count && *(char *)buf1 == *(char *)buf2 ) {
buf1 = (char *)buf1 + 1;
return(start);
}
12.//*************************************************************************************
char * __cdecl strcat (
char * dst,
void * __cdecl memset (
void *dst,
int val,
size_t count
)
{
void *start = dst;
while (count--) {
*(char *)dst = (char)val;
char * __cdecl _strset (
char * string,
int val
)
{
char *start = string;
while (*string)
*string++ = (char)val;
void * __cdecl memchr (
const void * buf,
int chr,
size_t cnt
)
{
while ( cnt && (*(unsigned char *)buf != (unsigned char)chr) ) {
long __cdecl atol(
const char *nptr
)
{
int c; /* current char */
long total; /* current total */
const char * src
)
{
char * cp = dst;
while( *cp )
cp++; /* find end of dst */
while( *cp++ = *src++ ) ; /* Copy src to end of dst */
dst = (char *)dst + 1;
}
return(start);
}
11.//*************************************************************************************
return( dst ); /* return dst */
}
13.//*************************************************************************************
{
char temp=*(Array+i);
*(Array+i)=*(Array+len-1-i);
*(Array+len-1-i)=temp;
}
*(Array+len)='\0';
return Array;
}
2.//**************************************************************************************
size_t strlen (const char * str)
{
const char *eos = str;
while( *eos++ ) ;
return( eos - str - 1 );
}
8.//**************************************************************************************
if ( ret < 0 )
ret = -1 ;
else if ( ret > 0 )
ret = 1 ;
return( ret );
}
7.//**************************************************************************************
1.//**************************************************************************************
char* reverse(char* Array)
{
int len = strlen(Array);
for(int i=0;i<len/2;i++)
int strcmp (const char * src, const char * dst)
{
int ret = 0 ;
while( ! (ret = *(unsigned char *)src - *(unsigned char *)dst) && *dst)
++src, ++dst;
*(char *)dst = *(char *)src;
dst = (char *)dst + 1;
src = (char *)src + 1;
}
return(ret);
}
3.//**************************************************************************************
判断一个链表是否为循环链表(追赶法)
bool isLoop(link *head)
{
link *p = head;
{
if (!*sp)
return buf;
}
buf += 1;
}
return NULL;
}