libbb: introduce and use is_prefixed_with()
function old new delta
is_prefixed_with - 18 +18
complete_username 78 77 -1
man_main 737 735 -2
fsck_device 429 427 -2
unpack_ar_archive 80 76 -4
strip_unsafe_prefix 105 101 -4
singlemount 1054 1050 -4
rtc_adjtime_is_utc 90 86 -4
resolve_mount_spec 88 84 -4
parse_one_line 1029 1025 -4
parse_conf 1460 1456 -4
may_wakeup 83 79 -4
loadkmap_main 219 215 -4
get_irqs_from_stat 103 99 -4
get_header_cpio 913 909 -4
findfs_main 79 75 -4
fbsplash_main 1230 1226 -4
load_crontab 776 771 -5
expand_vars_to_list 1151 1146 -5
date_main 881 876 -5
skip_dev_pfx 30 24 -6
make_device 2199 2193 -6
complete_cmd_dir_file 773 767 -6
run_applet_and_exit 715 708 -7
uudecode_main 321 313 -8
pwdx_main 197 189 -8
execute 568 560 -8
i2cdetect_main 1186 1176 -10
procps_scan 1242 1230 -12
procps_read_smaps 1017 1005 -12
process_module 746 734 -12
patch_main 1903 1891 -12
nfsmount 3572 3560 -12
stack_machine 126 112 -14
process_timer_stats 449 435 -14
match_fstype 111 97 -14
do_ipaddr 1344 1330 -14
open_list_and_close 359 343 -16
get_header_tar 1795 1779 -16
prepend_new_eth_table 340 323 -17
fsck_main 1811 1794 -17
find_iface_state 56 38 -18
dnsd_main 1321 1303 -18
base_device 179 158 -21
find_keyword 104 82 -22
handle_incoming_and_exit 2785 2762 -23
parse_and_put_prompt 774 746 -28
modinfo 347 317 -30
find_action 204 171 -33
update_passwd 1470 1436 -34
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 0/49 up/down: 18/-540) Total: -522 bytes
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
diff --git a/libbb/compare_string_array.c b/libbb/compare_string_array.c
index 4b10cc1..e24815a 100644
--- a/libbb/compare_string_array.c
+++ b/libbb/compare_string_array.c
@@ -5,6 +5,24 @@
#include "libbb.h"
+char* FAST_FUNC is_prefixed_with(const char *string, const char *key)
+{
+#if 0 /* Two passes over key - probably slower */
+ int len = strlen(key);
+ if (strncmp(string, key, len) == 0)
+ return string + len;
+ return NULL;
+#else /* Open-coded */
+ while (*key != '\0') {
+ if (*key != *string)
+ return NULL;
+ key++;
+ string++;
+ }
+ return (char*)string;
+#endif
+}
+
/* returns the array index of the string */
/* (index of first match is returned, or -1) */
int FAST_FUNC index_in_str_array(const char *const string_array[], const char *key)
@@ -39,10 +57,9 @@
int FAST_FUNC index_in_substr_array(const char *const string_array[], const char *key)
{
int i;
- int len = strlen(key);
- if (len) {
+ if (key[0]) {
for (i = 0; string_array[i] != 0; i++) {
- if (strncmp(string_array[i], key, len) == 0) {
+ if (is_prefixed_with(string_array[i], key)) {
return i;
}
}