libbb: simplify parameter passing in is_in_supplementary_groups()

function                                             old     new   delta
is_in_supplementary_groups                            54      52      -2
nexpr                                                721     718      -3
test_exec                                            125     119      -6
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-11)             Total: -11 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

coreutils/test.c

@@ -426,8 +426,7 @@ struct test_statics {
 	/* set only by check_operator(), either to bogus struct
 	 * or points to matching operator_t struct. Never NULL. */
 	const struct operator_t *last_operator;
-	gid_t *group_array;
+	struct cached_groupinfo groupinfo;
-	int ngroups;
 #if BASH_TEST2
 	bool bash_test2;
 #endif
@@ -440,8 +439,7 @@ extern struct test_statics *BB_GLOBAL_CONST test_ptr_to_statics;
 #define S (*test_ptr_to_statics)
 #define args            (S.args         )
 #define last_operator   (S.last_operator)
-#define group_array     (S.group_array  )
+#define groupinfo       (S.groupinfo    )
-#define ngroups         (S.ngroups      )
 #define bash_test2      (S.bash_test2   )
 #define leaving         (S.leaving      )
 
@@ -449,7 +447,7 @@ extern struct test_statics *BB_GLOBAL_CONST test_ptr_to_statics;
 	XZALLOC_CONST_PTR(&test_ptr_to_statics, sizeof(S)); \
 } while (0)
 #define DEINIT_S() do { \
-	free(group_array); \
+	free(groupinfo.supplementary_array); \
 	free(test_ptr_to_statics); \
 } while (0)
 
@@ -644,7 +642,7 @@ static int is_a_group_member(gid_t gid)
 	if (gid == getgid() || gid == getegid())
 		return 1;
 
-	return is_in_supplementary_groups(&ngroups, &group_array, gid);
+	return is_in_supplementary_groups(&groupinfo, gid);
 }
 
 /*
@@ -654,8 +652,20 @@ static int is_a_group_member(gid_t gid)
  */
 static int test_st_mode(struct stat *st, int mode)
 {
-	unsigned int euid = geteuid();
+	enum { ANY_IX = S_IXUSR | S_IXGRP | S_IXOTH };
+	unsigned euid;
 
+//TODO	if (mode == X_OK) {
+//		/* Do we already know with no extra syscalls? */
+//		if (!S_ISREG(st->st_mode))
+//			return 0; /* not a regular file */
+//		if ((st->st_mode & ANY_IX) == 0)
+//			return 0; /* no one can execute */
+//		if ((st->st_mode & ANY_IX) == ANY_IX)
+//			return 1; /* anyone can execute */
+//	}
+
+	euid = geteuid();
 	if (euid == 0) {
 		/* Root can read or write any file. */
 		if (mode != X_OK)

include/libbb.h

@@ -1203,9 +1203,15 @@ void die_if_bad_username(const char* name) FAST_FUNC;
 gid_t *bb_getgroups(int *ngroups, gid_t *group_array) FAST_FUNC;
 /*
  * True if GID is in our getgroups() result.
- * getgroups() is cached in group_array[], to makse successive calls faster.
+ * getgroups() is cached in supplementary_array[], to make successive calls faster.
  */
-int FAST_FUNC is_in_supplementary_groups(int *pngroups, gid_t **pgroup_array, gid_t gid);
+struct cached_groupinfo {
+	//TODO? gid_t egid;
+	int ngroups;
+	gid_t *supplementary_array;
+};
+//TODO? int FAST_FUNC get_cached_egid(gid_t *egid);
+int FAST_FUNC is_in_supplementary_groups(struct cached_groupinfo *groupinfo, gid_t gid);
 
 #if ENABLE_FEATURE_UTMP
 void FAST_FUNC write_new_utmp(pid_t pid, int new_type, const char *tty_name, const char *username, const char *hostname);

libbb/bb_getgroups.c

@@ -47,16 +47,16 @@ gid_t* FAST_FUNC bb_getgroups(int *ngroups, gid_t *group_array)
 }
 
 /* Return non-zero if GID is in our supplementary group list. */
-int FAST_FUNC is_in_supplementary_groups(int *pngroups, gid_t **pgroup_array, gid_t gid)
+int FAST_FUNC is_in_supplementary_groups(struct cached_groupinfo *groupinfo, gid_t gid)
 {
 	int i;
 	int ngroups;
 	gid_t *group_array;
 
-	if (*pngroups == 0)
+	if (groupinfo->ngroups == 0)
-		*pgroup_array = bb_getgroups(pngroups, NULL);
+		groupinfo->supplementary_array = bb_getgroups(&groupinfo->ngroups, NULL);
-	ngroups = *pngroups;
+	ngroups = groupinfo->ngroups;
-	group_array = *pgroup_array;
+	group_array = groupinfo->supplementary_array;
 
 	/* Search through the list looking for GID. */
 	for (i = 0; i < ngroups; i++)

shell/ash.c

@@ -493,8 +493,7 @@ struct globals_misc {
 	/* Rarely referenced stuff */
 
 	/* Cached supplementary group array (for testing executable'ity of files) */
-	int ngroups;
+	struct cached_groupinfo groupinfo;
-	gid_t *group_array;
 
 #if ENABLE_ASH_RANDOM_SUPPORT
 	random_t random_gen;
@@ -528,8 +527,7 @@ extern struct globals_misc *BB_GLOBAL_CONST ash_ptr_to_globals_misc;
 #define may_have_traps    (G_misc.may_have_traps   )
 #define trap        (G_misc.trap       )
 #define trap_ptr    (G_misc.trap_ptr   )
-#define ngroups     (G_misc.ngroups    )
+#define groupinfo   (G_misc.groupinfo  )
-#define group_array (G_misc.group_array)
 #define random_gen  (G_misc.random_gen )
 #define backgndpid  (G_misc.backgndpid )
 #define INIT_G_misc() do { \
@@ -13821,7 +13819,7 @@ static int test_exec(/*const char *fullname,*/ struct stat *statb)
 		stmode = S_IXUSR;
 	else if (statb->st_gid == getegid())
 		stmode = S_IXGRP;
-	else if (is_in_supplementary_groups(&ngroups, &group_array, statb->st_gid))
+	else if (is_in_supplementary_groups(&groupinfo, statb->st_gid))
 		stmode = S_IXGRP;
 
 	return statb->st_mode & stmode;