//都是自己編寫的，僅供學習參考。
date: 2009.6.24
author: summon
function: functions for string.h
version: v1.0
right: all right opened
char *mystrcpy(char *pchdest, const char *pchsour)
char *ret = pchdest;
dowhile (*pchsour != '/0');
*pchdest = '/0';
return ret;
}char *mystrncpy(char *pchdest, const char *pchsour, size_t count)
if (count == 0)
char *ret = pchdest;
while (count--)
}*pchdest = '/0';
return ret;
}int mystrcmp(const char *pchstr1, const char *pchstr2)
int ret = 0;
while (*pchstr1 == *pchstr2)
}ret = *(unsigned char *)pchstr1 - *(unsigned char *)pchstr2;
return ret;}//
int mystrlen(const char *pchdest
int ret = 0;
while(*pchdest != 0)
return ret;
}int mystrncmp(const char *pchstr1, const char *pchstr2, size_t count)
if (count == 0)
int ret = 0;
while (count--)
pchstr1++;
pchstr2++;//必須放到上個if後面再++
continue;
}else
}ret = *(unsigned char *)--pchstr1 - *(unsigned char *)--pchstr2;
return ret;//必須--才能返回正確的值，否則會向後移乙個字元才比較}/
void *mymovememery(void *pdest, const void *psrc, size_t nsize)
if (nsize == 0)
//input detected
void *ret = pdest;//remain the old pointer
unsigned char *d = (unsigned char *)pdest;//change to the most small memory unit
unsigned char *s = (unsigned char *)psrc;
if (d < s + nsize)//special memory overlap
}else
}return ret;
//return the old pointer
}char *mystrcat(char *pchdestination, const char *pchsource)
char *ret = pchdestination;
while (*pchdestination != '/0')
while (*pchsource != '/0')
*pchdestination = '/0';
return ret;
}char *mystrncat(char *pchdestination, const char *pchsource, size_t count)
if (count == 0)
char *ret = pchdestination;
while (*pchdestination != '/0')
while (count--)
else
}
*pchdestination = '/0';
return ret;
}char *mystrchr(const char *pstr, int find)
if (find == 0)
char *ret = (char *)pstr;
while (*ret != '/0')
ret++;
}return null;
}void *mymemchr(const void *pstr, int find, size_t count)
const unsigned char *p = (const unsigned char *)pstr;//為什麼要轉換成這種型別呢？
while (count--)
else
}return null;
}int mymemcmp(const void *pchstr1, const void *pchstr2, size_t count)
if (count == 0)
int ret = 0;
const unsigned char *p1 = (const unsigned char *)pchstr1;//比較記憶體都要轉換為最小儲存單位
const unsigned char *p2 = (const unsigned char *)pchstr2;
while (count--)
else
}return ret;}/
void *mymemset(void *pchdest, int set, size_t count)
if (count == 0)
unsigned char *p = (unsigned char *)pchdest;
unsigned char s = (unsigned char)set;
while (count--)
return pchdest;
}
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