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>

1 files changed, 4 insertions, 8 deletions

diff --git a/modutils/modprobe.c b/modutils/modprobe.c
index 0e8aa9e..996de40 100644
--- a/modutils/modprobe.c
+++ b/modutils/modprobe.c
@@ -260,7 +260,7 @@ static void add_probe(const char *name)
 	llist_add_to_end(&G.probes, m);
 	G.num_unresolved_deps++;
 	if (ENABLE_FEATURE_MODUTILS_SYMBOLS
-	 && strncmp(m->modname, "symbol:", 7) == 0
+	 && is_prefixed_with(m->modname, "symbol:")
 	) {
 		G.need_symbols = 1;
 	}
@@ -353,22 +353,18 @@ static char *parse_and_add_kcmdline_module_options(char *options, const char *mo
 	char *kcmdline_buf;
 	char *kcmdline;
 	char *kptr;
-	int len;
 
 	kcmdline_buf = xmalloc_open_read_close("/proc/cmdline", NULL);
 	if (!kcmdline_buf)
 		return options;
 
 	kcmdline = kcmdline_buf;
-	len = strlen(modulename);
 	while ((kptr = strsep(&kcmdline, "\n\t ")) != NULL) {
-		if (strncmp(modulename, kptr, len) != 0)
-			continue;
-		kptr += len;
-		if (*kptr != '.')
+		char *after_modulename = is_prefixed_with(kptr, modulename);
+		if (!after_modulename || *after_modulename != '.')
 			continue;
 		/* It is "modulename.xxxx" */
-		kptr++;
+		kptr = after_modulename + 1;
 		if (strchr(kptr, '=') != NULL) {
 			/* It is "modulename.opt=[val]" */
 			options = gather_options_str(options, kptr);