mirror of
https://github.com/autc04/Retro68.git
synced 2024-11-29 12:50:35 +00:00
105 lines
2.2 KiB
C
105 lines
2.2 KiB
C
|
/*
|
||
|
|
FUNCTION
|
||
|
|
<<strcat>>---concatenate strings
|
||
|
|
|
||
|
|
INDEX
|
||
|
|
strcat
|
||
|
|
|
||
|
|
ANSI_SYNOPSIS
|
||
|
|
#include <string.h>
|
||
|
|
char *strcat(char *<[dst]>, const char *<[src]>);
|
||
|
|
|
||
|
|
TRAD_SYNOPSIS
|
||
|
|
#include <string.h>
|
||
|
|
char *strcat(<[dst]>, <[src]>)
|
||
|
|
char *<[dst]>;
|
||
|
|
char *<[src]>;
|
||
|
|
|
||
|
|
DESCRIPTION
|
||
|
|
<<strcat>> appends a copy of the string pointed to by <[src]>
|
||
|
|
(including the terminating null character) to the end of the
|
||
|
|
string pointed to by <[dst]>. The initial character of
|
||
|
|
<[src]> overwrites the null character at the end of <[dst]>.
|
||
|
|
|
||
|
|
RETURNS
|
||
|
|
This function returns the initial value of <[dst]>
|
||
|
|
|
||
|
|
PORTABILITY
|
||
|
|
<<strcat>> is ANSI C.
|
||
|
|
|
||
|
|
<<strcat>> requires no supporting OS subroutines.
|
||
|
|
|
||
|
|
QUICKREF
|
||
|
|
strcat ansi pure
|
||
|
|
*/
|
||
|
|
|
||
|
|
#include <string.h>
|
||
|
|
#include <limits.h>
|
||
|
|
|
||
|
|
/* Nonzero if X is aligned on a "long" boundary. */
|
||
|
|
#define ALIGNED(X) \
|
||
|
|
(((long)X & (sizeof (long) - 1)) == 0)
|
||
|
|
|
||
|
|
#if LONG_MAX == 2147483647L
|
||
|
|
#define DETECTNULL(X) (((X) - 0x01010101) & ~(X) & 0x80808080)
|
||
|
|
#else
|
||
|
|
#if LONG_MAX == 9223372036854775807L
|
||
|
|
/* Nonzero if X (a long int) contains a NULL byte. */
|
||
|
|
#define DETECTNULL(X) (((X) - 0x0101010101010101) & ~(X) & 0x8080808080808080)
|
||
|
|
#else
|
||
|
|
#error long int is not a 32bit or 64bit type.
|
||
|
|
#endif
|
||
|
|
#endif
|
||
|
|
|
||
|
|
#ifndef DETECTNULL
|
||
|
|
#error long int is not a 32bit or 64bit byte
|
||
|
|
#endif
|
||
|
|
|
||
|
|
|
||
|
|
/*SUPPRESS 560*/
|
||
|
|
/*SUPPRESS 530*/
|
||
|
|
|
||
|
|
char *
|
||
|
|
_DEFUN (strcat, (s1, s2),
|
||
|
|
char *s1 _AND
|
||
|
|
_CONST char *s2)
|
||
|
|
{
|
||
|
|
#if defined(PREFER_SIZE_OVER_SPEED) || defined(__OPTIMIZE_SIZE__)
|
||
|
|
char *s = s1;
|
||
|
|
|
||
|
|
while (*s1)
|
||
|
|
s1++;
|
||
|
|
|
||
|
|
while (*s1++ = *s2++)
|
||
|
|
;
|
||
|
|
return s;
|
||
|
|
#else
|
||
|
|
char *s = s1;
|
||
|
|
|
||
|
|
|
||
|
|
/* Skip over the data in s1 as quickly as possible. */
|
||
|
|
if (ALIGNED (s1))
|
||
|
|
{
|
||
|
|
unsigned long *aligned_s1 = (unsigned long *)s1;
|
||
|
|
while (!DETECTNULL (*aligned_s1))
|
||
|
|
aligned_s1++;
|
||
|
|
|
||
|
|
s1 = (char *)aligned_s1;
|
||
|
|
}
|
||
|
|
|
||
|
|
while (*s1)
|
||
|
|
s1++;
|
||
|
|
|
||
|
|
/* s1 now points to the its trailing null character, we can
|
||
|
|
just use strcpy to do the work for us now.
|
||
|
|
|
||
|
|
?!? We might want to just include strcpy here.
|
||
|
|
Also, this will cause many more unaligned string copies because
|
||
|
|
s1 is much less likely to be aligned. I don't know if its worth
|
||
|
|
tweaking strcpy to handle this better. */
|
||
|
|
strcpy (s1, s2);
|
||
|
|
|
||
|
|
return s;
|
||
|
|
#endif /* not PREFER_SIZE_OVER_SPEED */
|
||
|
|
}
|