| /* strtok (str, delim) -- Return next DELIM separated token from STR. |
| For Intel 80686. |
| Copyright (C) 1998-2014 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| Contributed by Ulrich Drepper <drepper@cygnus.com>, 1998. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Lesser General Public |
| License as published by the Free Software Foundation; either |
| version 2.1 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 |
| Lesser General Public License for more details. |
| |
| You should have received a copy of the GNU Lesser General Public |
| License along with the GNU C Library; if not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #include <sysdep.h> |
| #include "asm-syntax.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. */ |
| |
| #ifdef USE_AS_STRTOK_R |
| # define SAVE_PTR 0(%ecx) |
| #else |
| .bss |
| .local save_ptr |
| .type save_ptr, @object |
| .size save_ptr, 4 |
| save_ptr: |
| .space 4 |
| |
| # ifdef PIC |
| # define SAVE_PTR save_ptr@GOTOFF(%ebx) |
| # else |
| # define SAVE_PTR save_ptr |
| # endif |
| |
| # define FUNCTION strtok |
| #endif |
| |
| #if !defined USE_AS_STRTOK_R && defined PIC |
| # define PARMS 4+256+4 /* space for table and saved PIC register */ |
| #else |
| # define PARMS 4+256 /* space for table */ |
| #endif |
| #define RTN PARMS |
| #define STR RTN |
| #define DELIM STR+4 |
| #ifdef USE_AS_STRTOK_R |
| # define SAVE DELIM+4 |
| #endif |
| |
| .text |
| |
| #if !defined USE_AS_STRTOK_R && defined PIC |
| 0: movl (%esp), %ebx |
| ret |
| #endif |
| |
| ENTRY (FUNCTION) |
| |
| #if !defined USE_AS_STRTOK_R && defined PIC |
| pushl %ebx /* Save PIC register. */ |
| cfi_adjust_cfa_offset (4) |
| cfi_rel_offset (ebx, 0) |
| call 0b |
| addl $_GLOBAL_OFFSET_TABLE_, %ebx |
| #endif |
| |
| /* 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. */ |
| movl %edi, %edx |
| subl $256, %esp |
| cfi_adjust_cfa_offset (256) |
| movl $64, %ecx |
| movl %esp, %edi |
| xorl %eax, %eax |
| cld |
| rep |
| stosl |
| |
| /* Note: %ecx = 0 !!! */ |
| movl %edx, %edi |
| |
| movl STR(%esp), %edx /* Get start of string. */ |
| |
| #ifdef USE_AS_STRTOK_R |
| /* The value is stored in the third argument. */ |
| movl SAVE(%esp), %eax |
| movl (%eax), %eax |
| #else |
| /* The value is in the local variable defined above. But |
| we have to take care for PIC code. */ |
| movl SAVE_PTR, %eax |
| #endif |
| |
| /* If the pointer is NULL we have to use the stored value of |
| the last run. */ |
| cmpl $0, %edx |
| cmove %eax, %edx |
| testl %edx, %edx |
| jz L(returnNULL) |
| movl DELIM(%esp), %eax /* Get start of delimiter set. */ |
| |
| /* 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. */ |
| |
| L(2): movb (%eax), %cl /* get byte from stopset */ |
| testb %cl, %cl /* is NUL char? */ |
| jz L(1) /* 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 L(1) /* 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 L(1) /* 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 L(2) /* no => process next dword from stopset */ |
| |
| L(1): 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. */ |
| |
| L(3): 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 L(4) /* no => start of token */ |
| |
| movb 1(%eax), %cl /* get byte from string */ |
| testb %cl, (%esp,%ecx) /* is it contained in stopset? */ |
| jz L(5) /* no => start of token */ |
| |
| movb 2(%eax), %cl /* get byte from string */ |
| testb %cl, (%esp,%ecx) /* is it contained in stopset? */ |
| jz L(6) /* no => start of token */ |
| |
| movb 3(%eax), %cl /* get byte from string */ |
| testb %cl, (%esp,%ecx) /* is it contained in stopset? */ |
| jnz L(3) /* yes => start of loop */ |
| |
| incl %eax /* adjust pointer */ |
| L(6): incl %eax |
| L(5): incl %eax |
| |
| /* Now we have to terminate the string. */ |
| |
| L(4): leal -4(%eax), %edx /* We use %EDX for the next run. */ |
| |
| L(7): 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 L(8) /* yes => return */ |
| |
| movb 1(%edx), %cl /* get byte from string */ |
| cmpb %cl, (%esp,%ecx) /* is it contained in skipset? */ |
| je L(9) /* yes => return */ |
| |
| movb 2(%edx), %cl /* get byte from string */ |
| cmpb %cl, (%esp,%ecx) /* is it contained in skipset? */ |
| je L(10) /* yes => return */ |
| |
| movb 3(%edx), %cl /* get byte from string */ |
| cmpb %cl, (%esp,%ecx) /* is it contained in skipset? */ |
| jne L(7) /* no => start loop again */ |
| |
| incl %edx /* adjust pointer */ |
| L(10): incl %edx |
| L(9): incl %edx |
| |
| L(8): cmpl %eax, %edx |
| je L(returnNULL) /* There was no token anymore. */ |
| |
| movb $0, (%edx) /* Terminate string. */ |
| |
| /* Are we at end of string? */ |
| cmpb $0, %cl |
| leal 1(%edx), %ecx |
| cmovne %ecx, %edx |
| |
| /* Store the pointer to the next character. */ |
| #ifdef USE_AS_STRTOK_R |
| movl SAVE(%esp), %ecx |
| #endif |
| movl %edx, SAVE_PTR |
| |
| L(epilogue): |
| /* Remove the stopset table. */ |
| addl $256, %esp |
| cfi_adjust_cfa_offset (-256) |
| #if !defined USE_AS_STRTOK_R && defined PIC |
| popl %ebx |
| cfi_adjust_cfa_offset (-4) |
| cfi_restore (ebx) |
| #endif |
| ret |
| |
| L(returnNULL): |
| xorl %eax, %eax |
| #ifdef USE_AS_STRTOK_R |
| movl SAVE(%esp), %ecx |
| #endif |
| movl %edx, SAVE_PTR |
| jmp L(epilogue) |
| |
| END (FUNCTION) |
