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, 6 deletions

diff --git a/miscutils/devfsd.c b/miscutils/devfsd.c
index 96ffe0738..5a6aec6bd 100644
--- a/miscutils/devfsd.c
+++ b/miscutils/devfsd.c
@@ -1405,7 +1405,6 @@ const char *get_old_name(const char *devname, unsigned int namelen,
         int indexx;
         const char *pty1;
         const char *pty2;
-        size_t len;
         /* 1 to 5  "scsi/" , 6 to 9 "ide/host", 10 sbp/, 11 vcc/, 12 pty/ */
         static const char *const fmt[] = {
                 NULL ,
@@ -1425,12 +1424,11 @@ const char *get_old_name(const char *devname, unsigned int namelen,
         };
 
         for (trans = translate_table; trans->match != NULL; ++trans) {
-                len = strlen(trans->match);
-
-                if (strncmp(devname, trans->match, len) == 0) {
+                char *after_match = is_prefixed_with(devname, trans->match);
+                if (after_match) {
                         if (trans->format == NULL)
-                                return devname + len;
-                        sprintf(buffer, trans->format, devname + len);
+                                return after_match;
+                        sprintf(buffer, trans->format, after_match);
                         return buffer;
                 }
         }