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/* strtok (str, delim) -- Return next DELIM separated token from STR.
For Intel 80x86, x>=3.
Copyright (C) 1996 Free Software Foundation, Inc.
This file is part of the GNU C Library.
Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
The GNU C 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 of the
License, or (at your option) any later version.
The GNU C 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with the GNU C Library; see the file COPYING.LIB. If
not, write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA. */
#include <sysdep.h>
/* This file can be used for three variants of the strtok function:
strtok:
INPUT PARAMETER:
str (sp + 4)
delim (sp + 8)
strtok_r:
INPUT PARAMETER:
str (sp + 4)
delim (sp + 8)
save_ptr (sp + 12)
We do a common implementation here. */
#ifndef USE_AS_STRTOK_R
.bss
.local save_ptr
ASM_TYPE_DIRECTIVE (save_ptr, @object)
.size save_ptr, 4
save_ptr:
.space 4
#define FUNCTION strtok
#endif
.text
ENTRY (FUNCTION)
movl 4(%esp), %edx /* Get start of string. */
movl 8(%esp), %eax /* Get start of delimiter set. */
#if !defined (USE_AS_STRTOK_R) && defined (PIC)
pushl %ebx /* Save PIC register. */
call Lhere
Lhere: popl %ebx
addl $_GLOBAL_OFFSET_TABLE_+[.-Lhere], %ebx
#endif
/* If the pointer is NULL we have to use the stored value of
the last run. */
cmpl $0, %edx
jne L0
#ifdef USE_AS_STRTOK_R
/* The value is stored in the third argument. */
movl 12(%esp), %edx
movl (%edx), %edx
#else
/* The value is in the local variable defined above. But
we have to take care for PIC code. */
# ifndef PIC
movl save_ptr, %edx
# else
movl save_ptr@GOTOFF(%ebx), %edx
# endif
#endif
L0:
/* First we create a table with flags for all possible characters.
For the ASCII (7bit/8bit) or ISO-8859-X character sets which are
supported by the C string functions we have 256 characters.
Before inserting marks for the stop characters we clear the whole
table. The unrolled form is much faster than a loop. */
xorl %ecx, %ecx /* %ecx = 0 !!! */
pushl %ecx /* make a 256 bytes long block filled with 0 */
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl %ecx
pushl $0 /* These immediate values make the label 2 */
pushl $0 /* to be aligned on a 16 byte boundary to */
pushl $0 /* get a better performance of the loop. */
pushl $0
pushl $0
pushl $0
/* For understanding the following code remember that %ecx == 0 now.
Although all the following instruction only modify %cl we always
have a correct zero-extended 32-bit value in %ecx. */
L2: movb (%eax), %cl /* get byte from stopset */
testb %cl, %cl /* is NUL char? */
jz L1 /* yes => start compare loop */
movb %cl, (%esp,%ecx) /* set corresponding byte in stopset table */
movb 1(%eax), %cl /* get byte from stopset */
testb $0xff, %cl /* is NUL char? */
jz L1 /* yes => start compare loop */
movb %cl, (%esp,%ecx) /* set corresponding byte in stopset table */
movb 2(%eax), %cl /* get byte from stopset */
testb $0xff, %cl /* is NUL char? */
jz L1 /* yes => start compare loop */
movb %cl, (%esp,%ecx) /* set corresponding byte in stopset table */
movb 3(%eax), %cl /* get byte from stopset */
addl $4, %eax /* increment stopset pointer */
movb %cl, (%esp,%ecx) /* set corresponding byte in stopset table */
testb $0xff, %cl /* is NUL char? */
jnz L2 /* no => process next dword from stopset */
L1: leal -4(%edx), %eax /* prepare loop */
/* We use a neat trick for the following loop. Normally we would
have to test for two termination conditions
1. a character in the stopset was found
and
2. the end of the string was found
As a sign that the character is in the stopset we store its
value in the table. The value of NUL is NUL so the loop
terminates for NUL in every case. */
L3: addl $4, %eax /* adjust pointer for full loop round */
movb (%eax), %cl /* get byte from string */
testb %cl, (%esp,%ecx) /* is it contained in stopset? */
jz L4 /* no => start of token */
movb 1(%eax), %cl /* get byte from string */
testb %cl, (%esp,%ecx) /* is it contained in stopset? */
jz L5 /* no => start of token */
movb 2(%eax), %cl /* get byte from string */
testb %cl, (%esp,%ecx) /* is it contained in stopset? */
jz L6 /* no => start of token */
movb 3(%eax), %cl /* get byte from string */
testb %cl, (%esp,%ecx) /* is it contained in stopset? */
jnz L3 /* yes => start of loop */
incl %eax /* adjust pointer */
L6: incl %eax
L5: incl %eax
/* Now we have to terminate the string. */
L4: leal -4(%eax), %edx /* We use %EDX for the next run. */
L7: addl $4, %edx /* adjust pointer for full loop round */
movb (%edx), %cl /* get byte from string */
cmpb %cl, (%esp,%ecx) /* is it contained in skipset? */
je L8 /* yes => return */
movb 1(%edx), %cl /* get byte from string */
cmpb %cl, (%esp,%ecx) /* is it contained in skipset? */
je L9 /* yes => return */
movb 2(%edx), %cl /* get byte from string */
cmpb %cl, (%esp,%ecx) /* is it contained in skipset? */
je L10 /* yes => return */
movb 3(%edx), %cl /* get byte from string */
cmpb %cl, (%esp,%ecx) /* is it contained in skipset? */
jne L7 /* no => start loop again */
incl %edx /* adjust pointer */
L10: incl %edx
L9: incl %edx
L8: /* Remove the stopset table. */
addl $256, %esp
cmpl %eax, %edx
je LreturnNULL /* There was no token anymore. */
movb $0, (%edx) /* Terminate string. */
/* Are we at end of string? */
cmpb $0, %cl
je L11
incl %edx
L11:
/* Store the pointer to the next character. */
#ifdef USE_AS_STRTOK_R
movl 12(%esp), %ecx
movl %edx, (%ecx)
#else
# ifndef PIC
movl %edx, save_ptr
# else
movl %edx, save_ptr@GOTOFF(%ebx)
popl %ebx
# endif
#endif
ret
LreturnNULL:
xorl %eax, %eax
/* Store current pointer for next round. */
#ifdef USE_AS_STRTOK_R
movl 12(%esp), %ecx
movl %edx, (%ecx)
#else
# ifndef PIC
movl %edx, save_ptr
# else
movl %edx, save_ptr@GOTOFF(%ebx)
popl %ebx
# endif
#endif
ret
END (FUNCTION)
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