strchr.c
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- /* Copyright (C) 2000 MySQL AB
- This program is free software; you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation; either version 2 of the License, or
- (at your option) any later version.
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
- You should have received a copy of the GNU General Public License
- along with this program; if not, write to the Free Software
- Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
- /* File : strchr.c
- Author : Richard A. O'Keefe.
- Michael Widenius: ifdef MC68000
- Updated: 20 April 1984
- Defines: strchr(), index()
- strchr(s, c) returns a pointer to the first place in s where c
- occurs, or NullS if c does not occur in s. This function is called
- index in V7 and 4.?bsd systems; while not ideal the name is clearer
- than strchr, so index remains in strings.h as a macro. NB: strchr
- looks for single characters, not for sets or strings. To find the
- NUL character which closes s, use strchr(s, ' ') or strend(s). The
- parameter 'c' is declared 'int' so it will go in a register; if your
- C compiler is happy with register _char_ change it to that.
- */
- #include "strings.h"
- #if defined(MC68000) && defined(DS90)
- char* strchr(char *s, pchar c)
- {
- asm(" movl 4(a7),a0 ");
- asm(" movl 8(a7),d1 ");
- asm(".L2: movb (a0)+,d0 ");
- asm(" cmpb d0,d1 ");
- asm(" beq .L1 ");
- asm(" tstb d0 ");
- asm(" bne .L2 ");
- asm(" moveq #0,d0 ");
- asm(" rts ");
- asm(".L1: movl a0,d0 ");
- asm(" subql #1,d0 ");
- }
- #else
- char *strchr(register const char *s, register pchar c)
- {
- for (;;)
- {
- if (*s == (char) c) return (char*) s;
- if (!*s++) return NullS;
- }
- }
- #endif