/*-------------------------------------------------------------------------
- _strcpy.c - part of string library functions
+ _strlen.c - part of string library functions
Written By - Sandeep Dutta . sandeep.dutta@usa.net (1999)
+ mcs51 assembler by Frieder Ferlemann (2007)
- 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
+ This library is free software; you can redistribute it and/or modify it
+ under the terms of the GNU Library General Public License as published by the
Free Software Foundation; either version 2, or (at your option) any
later version.
-
- This program is distributed in the hope that it will be useful,
+
+ This library 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
+ GNU Library General Public License for more details.
+
+ You should have received a copy of the GNU Library General Public License
along with this program; if not, write to the Free Software
Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
-
+
In other words, you are welcome to use, share and improve this program.
You are forbidden to forbid anyone else to use, share and improve
- what you give them. Help stamp out software-hoarding!
+ what you give them. Help stamp out software-hoarding!
-------------------------------------------------------------------------*/
-#include "string.h"
-#define NULL (void *)0
-int strlen ( char _generic *str )
-{
- register int i = 0 ;
+#if (!defined (SDCC_mcs51))
+
+ /* Generic routine first */
+ int strlen ( char * str )
+ {
+ register int i = 0 ;
+
+ while (*str++)
+ i++ ;
+
+ return i;
+ }
+
+#else
+
+ /* Assembler version for mcs51 */
+ int strlen ( char * str ) __naked
+ {
+ str; /* hush the compiler */
+
+ __asm
+ ; dptr holds pointer
+ ; b holds pointer memspace
+ ;
+
+ ; char *ptr = str:
+ mov r2,dpl
+ mov r3,dph
+ ;
+
+ ; while ( *ptr ) ptr++;
+ L00101$:
+ lcall __gptrget
+ jz L00102$
+ inc dptr
+ sjmp L00101$
+ ;
- while (*str++)
- i++ ;
+ L00102$:
+ ; return ptr - str;
+ clr c
+ mov a,dpl
+ subb a,r2
+ mov dpl,a
+ ;
+ mov a,dph
+ subb a,r3
+ mov dph,a
+ ;
+ ret
+ __endasm;
+ }
- return i;
-}
+#endif