字符串库函数

char * __cdecl strcpy(char * dst, const char * src) { char * cp = dst; while( *cp++ = *src++ ) ; /* Copy src over dst */ return( dst ); }

 

char * __cdecl strcat ( char * dst, const char * src ) { char * cp = dst; while( *cp ) cp++; /* find end of dst */ while( *cp++ = *src++ ) ; /* Copy src to end of dst */ return( dst ); /* return dst */ }

int __cdecl strcmp ( const char * src, const char * dst ) { int ret = 0 ; while( ! (ret = *(unsigned char *)src - *(unsigned char *)dst) && *dst) ++src, ++dst; if ( ret < 0 ) ret = -1 ; else if ( ret > 0 ) ret = 1 ; return( ret ); }

char * __cdecl _strrev ( char * string ) { char *start = string; char *left = string; char ch; while (*string++) /* find end of string */ ; string -= 2; while (left < string) { ch = *left; *left++ = *string; *string-- = ch; } return(start); }

char * __cdecl strstr ( const char * str1, const char * str2 ) { char *cp = (char *) str1; char *s1, *s2; if ( !*str2 ) return((char *)str1); while (*cp) { s1 = cp; s2 = (char *) str2; while ( *s1 && *s2 && !(*s1-*s2) ) s1++, s2++; if (!*s2) return(cp); cp++; } return(NULL); }

size_t __cdecl strlen ( const char * str ) { const char *eos = str; while( *eos++ ) ; return( (int)(eos - str - 1) ); }

void * __cdecl memset ( void *dst, int val, size_t count ) { void *start = dst; #if defined (_M_MRX000) || defined (_M_ALPHA) || defined (_M_PPC) { extern void RtlFillMemory( void *, size_t count, char ); RtlFillMemory( dst, count, (char)val ); } #else /* defined (_M_MRX000) || defined (_M_ALPHA) || defined (_M_PPC) */ while (count--) { *(char *)dst = (char)val; dst = (char *)dst + 1; } #endif /* defined (_M_MRX000) || defined (_M_ALPHA) || defined (_M_PPC) */ return(start); }

void * __cdecl memcpy ( void * dst, const void * src, size_t count ) { void * ret = dst; #if defined (_M_MRX000) || defined (_M_ALPHA) || defined (_M_PPC) { extern void RtlMoveMemory( void *, const void *, size_t count ); RtlMoveMemory( dst, src, count ); } #else /* defined (_M_MRX000) || defined (_M_ALPHA) || defined (_M_PPC) */ /* * copy from lower addresses to higher addresses */ while (count--) { *(char *)dst = *(char *)src; dst = (char *)dst + 1; src = (char *)src + 1; } #endif /* defined (_M_MRX000) || defined (_M_ALPHA) || defined (_M_PPC) */ return(ret); }