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 57c972f..89dea3e 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 e2ed3ee..a5bd0e3 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 7b87a42..82d2664 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 cb4a4e4..42170bc 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 aa22441..07cae97 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 e80e764..6a699a7 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 693f609..ecd50a6 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 cfc5b34..1fafec8 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 1f2e6a5..62f8949 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 dfb616a..9daf4e1 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 dbed4ea..3861dd1 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 f78f96c..13f5ec2 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 383a006..8c5e29f 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 22005aa..17e5e88 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 */