[PATCH] modprobe: Implementation of -D (--show-depends) option.

[Serj Kalichev]

It can show all dependencies of specified module. The
module can be specified by alias.

Signed-off-by: Serj Kalichev <serj.kalichev at gmail.com>
---
 modutils/modprobe.c |   21 +++++++++++++++------
 1 files changed, 15 insertions(+), 6 deletions(-)

diff --git a/modutils/modprobe.c b/modutils/modprobe.c
index a5cf4ba..552fe2b 100644
--- a/modutils/modprobe.c
+++ b/modutils/modprobe.c
@@ -86,6 +86,7 @@
 //usage:	IF_FEATURE_MODPROBE_BLACKLIST(
 //usage:     "\n	-b	Apply blacklist to module names too"
 //usage:	)
+//usage:     "\n	-D	Show dependencies"
 //usage:#endif /* !ENABLE_MODPROBE_SMALL */
 
 #include "libbb.h"
@@ -105,7 +106,7 @@
  * we pull in through INSMOD_OPTS define */
 
 #define MODPROBE_COMPLEMENTARY "q-v:v-q:l--ar:a--lr:r--al"
-#define MODPROBE_OPTS  "alr" IF_FEATURE_MODPROBE_BLACKLIST("b")
+#define MODPROBE_OPTS  "alr" IF_FEATURE_MODPROBE_BLACKLIST("b") "D"
 //#define MODPROBE_COMPLEMENTARY "q-v:v-q:l--acr:a--lr:r--al"
 //#define MODPROBE_OPTS  "acd:lnrt:C:" IF_FEATURE_MODPROBE_BLACKLIST("b")
 enum {
@@ -119,6 +120,7 @@ enum {
 	//MODPROBE_OPT_VERONLY  = (INSMOD_OPT_UNUSED << x), /* V */
 	//MODPROBE_OPT_CONFIGFILE=(INSMOD_OPT_UNUSED << x), /* C */
 	MODPROBE_OPT_BLACKLIST  = (INSMOD_OPT_UNUSED << 3) * ENABLE_FEATURE_MODPROBE_BLACKLIST,
+	MODPROBE_OPT_SHOW_DEPS  = (INSMOD_OPT_UNUSED << 4), /* D */
 };
 
 #define MODULE_FLAG_LOADED              0x0001
@@ -202,7 +204,7 @@ static void add_probe(const char *name)
 	struct module_entry *m;
 
 	m = get_or_add_modentry(name);
-	if (!(option_mask32 & MODPROBE_OPT_REMOVE)
+	if (!(option_mask32 & (MODPROBE_OPT_REMOVE | MODPROBE_OPT_SHOW_DEPS))
 	 && (m->flags & MODULE_FLAG_LOADED)
 	) {
 		DBG("skipping %s, it is already loaded", name);
@@ -357,6 +359,7 @@ static int do_modprobe(struct module_entry *m)
 	char *fn, *options;
 	int rc, first;
 	llist_t *l;
+	struct utsname uts;
 
 	if (!(m->flags & MODULE_FLAG_FOUND_IN_MODDEP)) {
 		if (!(option_mask32 & INSMOD_OPT_SILENT))
@@ -374,6 +377,7 @@ static int do_modprobe(struct module_entry *m)
 
 	first = 1;
 	rc = 0;
+	uname(&uts);
 	while (m->deps) {
 		rc = 0;
 		fn = llist_pop(&m->deps); /* we leak it */
@@ -399,7 +403,8 @@ static int do_modprobe(struct module_entry *m)
 			continue;
 		}
 
-		if (m2->flags & MODULE_FLAG_LOADED) {
+		if ((m2->flags & MODULE_FLAG_LOADED) &&
+			!(option_mask32 & MODPROBE_OPT_SHOW_DEPS)) {
 			DBG("%s is already loaded, skipping", fn);
 			continue;
 		}
@@ -409,7 +414,11 @@ static int do_modprobe(struct module_entry *m)
 		options = parse_and_add_kcmdline_module_options(options, m2->modname);
 		if (m == m2)
 			options = gather_options_str(options, G.cmdline_mopts);
-		rc = bb_init_module(fn, options);
+		if (option_mask32 & MODPROBE_OPT_SHOW_DEPS)
+			printf("insmod %s/%s/%s\n", CONFIG_DEFAULT_MODULES_DIR,
+				uts.release, fn);
+		else
+			rc = bb_init_module(fn, options);
 		DBG("loaded %s '%s', rc:%d", fn, options, rc);
 		if (rc == EEXIST)
 			rc = 0;
@@ -456,7 +465,7 @@ static void load_modules_dep(void)
 
 		/* Optimization... */
 		if ((m->flags & MODULE_FLAG_LOADED)
-		 && !(option_mask32 & MODPROBE_OPT_REMOVE)
+		 && !(option_mask32 & (MODPROBE_OPT_REMOVE | MODPROBE_OPT_SHOW_DEPS))
 		) {
 			DBG("skip deps of %s, it's already loaded", tokens[0]);
 			continue;
@@ -592,7 +601,7 @@ int modprobe_main(int argc UNUSED_PARAM, char **argv)
 			m2 = get_or_add_modentry(realname);
 			if (!(m2->flags & MODULE_FLAG_BLACKLISTED)
 			 && (!(m2->flags & MODULE_FLAG_LOADED)
-			    || (opt & MODPROBE_OPT_REMOVE))
+			    || (opt & (MODPROBE_OPT_REMOVE | MODPROBE_OPT_SHOW_DEPS)))
 			) {
 //TODO: we can pass "me" as 2nd param to do_modprobe,
 //and make do_modprobe emit more meaningful error messages
-- 
1.7.3.3