introduce and use bb_basename()

function                                             old     new   delta
bb_basename                                            -      26     +26
sv_main                                             1226    1225      -1
passwd_main                                         1985    1983      -2
showdirs                                             482     478      -4
sendCgi                                             1811    1807      -4
make_device                                         1354    1350      -4
handleIncoming                                      2443    2439      -4
func_name                                             82      78      -4
service_name                                        2292    2285      -7
main                                                 909     901      -8
cmp_main                                             555     547      -8
test_main                                            434     422     -12
act                                                  228     216     -12
find_pair                                            180     164     -16
rmmod_main                                           298     280     -18
find_pid_by_name                                     156     134     -22
modprobe_main                                       1606    1576     -30
------------------------------------------------------------------------------
(add/remove: 1/0 grow/shrink: 0/16 up/down: 26/-156)         Total: -130 bytes
   text    data     bss     dec     hex filename
 734933    3028   14400  752361   b7ae9 busybox_old
 734801    3028   14400  752229   b7a65 busybox_unstripped

14 files changed, 40 insertions, 73 deletions

diff --git a/applets/applets.c b/applets/applets.c
index 57c972f79..89dea3e6a 100644
--- a/applets/applets.c
+++ b/applets/applets.c
@@ -639,8 +639,6 @@ int *const bb_errno __attribute__ ((section (".data")));
 
 int main(int argc, char **argv)
 {
-        const char *s;
-
 #ifdef __GLIBC__
         (*(int **)&bb_errno) = __errno_location();
 #endif
@@ -655,9 +653,7 @@ int main(int argc, char **argv)
         applet_name = argv[0];
         if (applet_name[0] == '-')
                 applet_name++;
-        s = strrchr(applet_name, '/');
-        if (s)
-                applet_name = s + 1;
+        applet_name = bb_basename(applet_name);
 
         parse_config_file(); /* ...maybe, if FEATURE_SUID_CONFIG */
 
diff --git a/coreutils/ls.c b/coreutils/ls.c
index e2ed3ee1f..a5bd0e304 100644
--- a/coreutils/ls.c
+++ b/coreutils/ls.c
@@ -132,8 +132,8 @@ enum { show_color = 0 };
  * a directory entry and its stat info are stored here
  */
 struct dnode {                  /* the basic node */
-        char *name;             /* the dir entry name */
-        char *fullname;         /* the dir entry name */
+        const char *name;             /* the dir entry name */
+        const char *fullname;         /* the dir entry name */
         int   allocated;
         struct stat dstat;      /* the file stat info */
         USE_SELINUX(security_context_t sid;)
@@ -159,7 +159,7 @@ enum {
 
 static int status = EXIT_SUCCESS;
 
-static struct dnode *my_stat(char *fullname, char *name, int force_follow)
+static struct dnode *my_stat(const char *fullname, const char *name, int force_follow)
 {
         struct stat dstat;
         struct dnode *cur;
@@ -241,7 +241,7 @@ static int count_dirs(struct dnode **dn, int nfiles, int notsubdirs)
                 return 0;
         dirs = 0;
         for (i = 0; i < nfiles; i++) {
-                char *name;
+                const char *name;
                 if (!S_ISDIR(dn[i]->dstat.st_mode))
                         continue;
                 name = dn[i]->name;
@@ -288,7 +288,7 @@ static void dfree(struct dnode **dnp, int nfiles)
         for (i = 0; i < nfiles; i++) {
                 struct dnode *cur = dnp[i];
                 if (cur->allocated)
-                        free(cur->fullname);    /* free the filename */
+                        free((char*)cur->fullname);     /* free the filename */
                 free(cur);              /* free the dnode */
         }
         free(dnp);                      /* free the array holding the dnode pointers */
@@ -320,7 +320,7 @@ static struct dnode **splitdnarray(struct dnode **dn, int nfiles, int which)
         /* copy the entrys into the file or dir array */
         for (d = i = 0; i < nfiles; i++) {
                 if (S_ISDIR(dn[i]->dstat.st_mode)) {
-                        char *name;
+                        const char *name;
                         if (!(which & (SPLIT_DIR|SPLIT_SUBDIR)))
                                 continue;
                         name = dn[i]->name;
@@ -513,7 +513,7 @@ static struct dnode **list_dir(const char *path)
                                 continue;
                 }
                 fullname = concat_path_file(path, entry->d_name);
-                cur = my_stat(fullname, strrchr(fullname, '/') + 1, 0);
+                cur = my_stat(fullname, bb_basename(fullname), 0);
                 if (!cur) {
                         free(fullname);
                         continue;
diff --git a/coreutils/test.c b/coreutils/test.c
index 7b87a42f9..82d2664a8 100644
--- a/coreutils/test.c
+++ b/coreutils/test.c
@@ -181,11 +181,10 @@ static void initialize_group_array(void);
 int test_main(int argc, char **argv)
 {
         int res;
-        char *arg0;
+        const char *arg0;
         bool _off;
 
-        arg0 = strrchr(argv[0], '/');
-        if (!arg0++) arg0 = argv[0];
+        arg0 = bb_basename(argv[0]);
         if (arg0[0] == '[') {
                 --argc;
                 if (!arg0[1]) { /* "[" ? */
diff --git a/debianutils/run_parts.c b/debianutils/run_parts.c
index cb4a4e4c7..42170bcb8 100644
--- a/debianutils/run_parts.c
+++ b/debianutils/run_parts.c
@@ -60,10 +60,7 @@ struct globals {
  */
 static bool invalid_name(const char *c)
 {
-        const char *base_name = strrchr(c, '/');
-
-        if (base_name)
-                c = base_name + 1;
+        c = bb_basename(c);
 
         while (*c && (isalnum(*c) || *c == '_' || *c == '-'))
                 c++;
diff --git a/findutils/find.c b/findutils/find.c
index aa2244141..07cae971e 100644
--- a/findutils/find.c
+++ b/findutils/find.c
@@ -180,18 +180,13 @@ static int exec_actions(action ***appp, const char *fileName, struct stat *statb
 
 ACTF(name)
 {
-        const char *tmp = strrchr(fileName, '/');
-        if (tmp == NULL)
-                tmp = fileName;
-        else {
-                tmp++;
-                if (!*tmp) { /* "foo/bar/". Oh no... go back to 'b' */
-                        tmp--;
-                        while (tmp != fileName && *--tmp != '/')
-                                continue;
-                        if (*tmp == '/')
-                                tmp++;
-                }
+        const char *tmp = bb_basename(fileName);
+        if (tmp != fileName && !*tmp) { /* "foo/bar/". Oh no... go back to 'b' */
+                tmp--;
+                while (tmp != fileName && *--tmp != '/')
+                        continue;
+                if (*tmp == '/')
+                        tmp++;
         }
         return fnmatch(ap->pattern, tmp, FNM_PERIOD) == 0;
 }
diff --git a/include/libbb.h b/include/libbb.h
index e80e76403..6a699a7e6 100644
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -736,6 +736,7 @@ extern int bb_parse_mode(const char* s, mode_t* theMode);
 
 char *concat_path_file(const char *path, const char *filename);
 char *concat_subpath_file(const char *path, const char *filename);
+const char *bb_basename(const char *name);
 /* NB: can violate const-ness (similarly to strchr) */
 char *last_char_is(const char *s, int c);
 
diff --git a/libbb/Kbuild b/libbb/Kbuild
index 693f6092c..ecd50a616 100644
--- a/libbb/Kbuild
+++ b/libbb/Kbuild
@@ -8,6 +8,7 @@ lib-y:=
 
 lib-y += ask_confirmation.o
 lib-y += bb_askpass.o
+lib-y += bb_basename.o
 lib-y += bb_do_delay.o
 lib-y += bb_pwd.o
 lib-y += bb_strtonum.o
diff --git a/libbb/find_pid_by_name.c b/libbb/find_pid_by_name.c
index cfc5b3468..1fafec83a 100644
--- a/libbb/find_pid_by_name.c
+++ b/libbb/find_pid_by_name.c
@@ -38,14 +38,6 @@ execXXX("/proc/self/exe", applet_name, params....)
 and therefore comm field contains "exe".
 */
 
-static const char *bb_basename(const char *name)
-{
-        const char *cp = strrchr(name, '/');
-        if (cp)
-                return cp + 1;
-        return name;
-}
-
 /* find_pid_by_name()
  *
  *  Modified by Vladimir Oleynik for use with libbb/procps.c
diff --git a/libbb/lineedit.c b/libbb/lineedit.c
index 1f2e6a54e..62f8949d6 100644
--- a/libbb/lineedit.c
+++ b/libbb/lineedit.c
@@ -1156,7 +1156,7 @@ static void parse_prompt(const char *prmt_ptr)
 #endif
                                 case 'W':
                                         pbuf = pwd_buf;
-                                        cp = strrchr(pbuf,'/');
+                                        cp = strrchr(pbuf, '/');
                                         if (cp != NULL && cp != pbuf)
                                                 pbuf += (cp-pbuf) + 1;
                                         break;
diff --git a/miscutils/devfsd.c b/miscutils/devfsd.c
index dfb616abe..9daf4e1cc 100644
--- a/miscutils/devfsd.c
+++ b/miscutils/devfsd.c
@@ -240,8 +240,8 @@ static void do_ioctl_and_die(int fd, int request, unsigned long event_mask_flag)
 static void fork_and_execute(int die, char *arg0, char **arg);
 static int get_uid_gid(int, const char *);
 static void safe_memcpy(char * dest, const char * src, int len);
-static unsigned int scan_dev_name_common(const char *d, unsigned int n, int addendum, char *ptr);
-static unsigned int scan_dev_name(const char *d, unsigned int n, char *ptr);
+static unsigned int scan_dev_name_common(const char *d, unsigned int n, int addendum, const char *ptr);
+static unsigned int scan_dev_name(const char *d, unsigned int n, const char *ptr);
 
 /* Structs and vars */
 static struct config_entry_struct *first_config = NULL;
@@ -369,7 +369,7 @@ static void safe_memcpy(char *dest, const char *src, int len)
         dest[len] = '\0';
 }
 
-static unsigned int scan_dev_name_common(const char *d, unsigned int n, int addendum, char *ptr)
+static unsigned int scan_dev_name_common(const char *d, unsigned int n, int addendum, const char *ptr)
 {
         if (d[n - 4] == 'd' && d[n - 3] == 'i' && d[n - 2] == 's' && d[n - 1] == 'c')
                 return 2 + addendum;
@@ -382,7 +382,7 @@ static unsigned int scan_dev_name_common(const char *d, unsigned int n, int adde
         return 0;
 }
 
-static unsigned int scan_dev_name(const char *d, unsigned int n, char *ptr)
+static unsigned int scan_dev_name(const char *d, unsigned int n, const char *ptr)
 {
         if (d[0] == 's' && d[1] == 'c' && d[2] == 's' && d[3] == 'i' && d[4] == '/') {
                 if (d[n - 7] == 'g' && d[n - 6] == 'e' && d[n - 5] == 'n'
@@ -926,7 +926,7 @@ static void action_compat(const struct devfsd_notify_struct *info, unsigned int
         int ret;
         const char *compat_name = NULL;
         const char *dest_name = info->devname;
-        char *ptr=NULL;
+        const char *ptr;
         char compat_buf[STRING_LENGTH], dest_buf[STRING_LENGTH];
         int mode, host, bus, target, lun;
         unsigned int i;
@@ -954,7 +954,7 @@ static void action_compat(const struct devfsd_notify_struct *info, unsigned int
                         break;
                 case AC_MKNEWCOMPAT:
                 case AC_RMNEWCOMPAT:
-                        ptr = strrchr(info->devname, '/') + 1;
+                        ptr = bb_basename(info->devname);
                         i = scan_dev_name(info->devname, info->namelen, ptr);
 
                         /* nothing found */
@@ -1460,7 +1460,7 @@ const char *get_old_name(const char *devname, unsigned int namelen,
 */
 {
         const char *compat_name = NULL;
-        char *ptr;
+        const char *ptr;
         struct translate_struct *trans;
         unsigned int i;
         char mode;
@@ -1497,7 +1497,7 @@ const char *get_old_name(const char *devname, unsigned int namelen,
                 }
         }
 
-        ptr = (strrchr(devname, '/') + 1);
+        ptr = bb_basename(devname);
         i = scan_dev_name(devname, namelen, ptr);
 
         if (i > 0 && i < 13)
diff --git a/modutils/modprobe.c b/modutils/modprobe.c
index dbed4ea0f..3861dd1e3 100644
--- a/modutils/modprobe.c
+++ b/modutils/modprobe.c
@@ -376,18 +376,13 @@ static struct dep_t *build_dep(void)
 
                         if (col) {
                                 /* This line is a dep description */
-                                char *mods;
+                                const char *mods;
                                 char *modpath;
                                 char *mod;
 
                                 /* Find the beginning of the module file name */
                                 *col = 0;
-                                mods = strrchr(buffer, '/');
-
-                                if (!mods)
-                                        mods = buffer; /* no path for this module */
-                                else
-                                        mods++; /* there was a path for this module... */
+                                mods = bb_basename(buffer);
 
                                 /* find the path of the module */
                                 modpath = strchr(buffer, '/'); /* ... and this is the path */
@@ -433,7 +428,7 @@ static struct dep_t *build_dep(void)
                 /* p points to the first dependable module; if NULL, no dependable module */
                 if (p && *p) {
                         char *end = &buffer[l-1];
-                        char *deps;
+                        const char *deps;
                         char *dep;
                         char *next;
                         int ext = 0;
@@ -451,15 +446,11 @@ static struct dep_t *build_dep(void)
                                         next = end;
 
                                 /* find the beginning of the module file name */
-                                deps = strrchr(p, '/');
-
-                                if (!deps || (deps < p)) {
-                                        deps = p;
-
+                                deps = bb_basename(p);
+                                if (deps == p) {
                                         while (isblank(*deps))
                                                 deps++;
-                                } else
-                                        deps++;
+                                }
 
                                 /* find the end of the module name in the file name */
                                 if (ENABLE_FEATURE_2_6_MODULES
diff --git a/modutils/rmmod.c b/modutils/rmmod.c
index f78f96ccc..13f5ec20b 100644
--- a/modutils/rmmod.c
+++ b/modutils/rmmod.c
@@ -81,12 +81,7 @@ int rmmod_main(int argc, char **argv)
 
         for (n = optind; n < argc; n++) {
                 if (ENABLE_FEATURE_2_6_MODULES) {
-                        const char *afterslash;
-
-                        afterslash = strrchr(argv[n], '/');
-                        if (!afterslash) afterslash = argv[n];
-                        else afterslash++;
-                        filename2modname(misc_buf, afterslash);
+                        filename2modname(misc_buf, bb_basename(argv[n]));
                 }
 
                 if (syscall(__NR_delete_module, ENABLE_FEATURE_2_6_MODULES ? misc_buf : argv[n], flags)) {
diff --git a/networking/httpd.c b/networking/httpd.c
index 383a00635..8c5e29fa8 100644
--- a/networking/httpd.c
+++ b/networking/httpd.c
@@ -1125,7 +1125,7 @@ static int sendCgi(const char *url,
                         setenv1("HTTP_REFERER", referer);
 
                 /* set execve argp[0] without path */
-                argp[0] = strrchr(purl, '/') + 1;
+                argp[0] = (char*)bb_basename(purl);
                 /* but script argp[0] must have absolute path and chdiring to this */
                 script = strrchr(fullpath, '/');
                 if (!script)
@@ -1713,7 +1713,7 @@ static void handleIncoming(void)
                 if (alarm_signaled)
                         break;
 
-                if (strcmp(strrchr(url, '/') + 1, httpd_conf) == 0 || ip_allowed == 0) {
+                if (strcmp(bb_basename(url), httpd_conf) == 0 || ip_allowed == 0) {
                         /* protect listing [/path]/httpd_conf or IP deny */
 #if ENABLE_FEATURE_HTTPD_CGI
  FORBIDDEN:             /* protect listing /cgi-bin */
diff --git a/util-linux/mdev.c b/util-linux/mdev.c
index 22005aaee..17e5e88c6 100644
--- a/util-linux/mdev.c
+++ b/util-linux/mdev.c
@@ -24,7 +24,7 @@ struct globals {
 /* mknod in /dev based on a path like "/sys/block/hda/hda1" */
 static void make_device(char *path, int delete)
 {
-        char *device_name;
+        const char *device_name;
         int major, minor, type, len;
         int mode = 0660;
         uid_t uid = 0;
@@ -46,7 +46,7 @@ static void make_device(char *path, int delete)
 
         /* Determine device name, type, major and minor */
 
-        device_name = strrchr(path, '/') + 1;
+        device_name = bb_basename(path);
         type = path[5]=='c' ? S_IFCHR : S_IFBLK;
 
         /* If we have a config file, look up permissions for this device */