ahp/busybox
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

libbb: auto_string() for efficient handling of temporary malloced stirngs

Browse source 
Use it in libiproute: get rid of one static string buffer.

function                                             old     new   delta
auto_string                                            -      51     +51
ll_index_to_name                                      10      49     +39
buffer_fill_and_print                                169     178      +9
scan_recursive                                       378     380      +2
decode_one_format                                    732     734      +2
cmdputs                                              334     332      -2
static.cur_saved                                       4       1      -3
static.nbuf                                           16       -     -16
printable_string                                      94      57     -37
ll_idx_n2a                                            53       -     -53
------------------------------------------------------------------------------
(add/remove: 2/2 grow/shrink: 4/3 up/down: 103/-111)           Total: -8 bytes
   text	   data	    bss	    dec	    hex	filename
 939880	    992	  17496	 958368	  e9fa0	busybox_old
 939880	    992	  17480	 958352	  e9f90	busybox_unstripped

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2015-10-09 17:59:56 +02:00
parent 550bf5b4a4
commit e52da5570e
5 changed files with 33 additions and 16 deletions
Download patch file Download diff file Expand all files Collapse all files

23
libbb/auto_string.c Normal file
View file

@ -0,0 +1,23 @@
/* vi: set sw=4 ts=4: */
/*
* Utility routines.
*
* Copyright (C) 2015 Denys Vlasenko
*
* Licensed under GPLv2, see file LICENSE in this source tree.
*/
//kbuild:lib-y += auto_string.o
#include "libbb.h"
char* FAST_FUNC auto_string(char *str)
{
static char *saved[4];
static uint8_t cur_saved; /* = 0 */
free(saved[cur_saved]);
saved[cur_saved] = str;
cur_saved = (cur_saved + 1) & (ARRAY_SIZE(saved)-1);
return str;
}