1 files changed, 57 insertions, 21 deletions

diff --git a/coreutils/id.c b/coreutils/id.c
index 42ed4c749..399d25e34 100644
--- a/coreutils/id.c
+++ b/coreutils/id.c
@@ -15,11 +15,28 @@
  * Added -G option Tito Ragusa (C) 2008 for SUSv3.
  */
 
+//config:config ID
+//config:       bool "id"
+//config:       default y
+//config:       help
+//config:         id displays the current user and group ID names.
+
+//config:config GROUPS
+//config:       bool "groups"
+//config:       default y
+//config:       help
+//config:         Print the group names associated with current user id.
+
+//kbuild:lib-$(CONFIG_GROUPS) += id.o
+//kbuild:lib-$(CONFIG_ID)     += id.o
+
+//applet:IF_GROUPS(APPLET_NOEXEC(groups, id, BB_DIR_USR_BIN, BB_SUID_DROP, groups))
+//applet:IF_ID(    APPLET_NOEXEC(id,     id, BB_DIR_USR_BIN, BB_SUID_DROP, id    ))
+
 //usage:#define id_trivial_usage
 //usage:       "[OPTIONS] [USER]"
 //usage:#define id_full_usage "\n\n"
 //usage:       "Print information about USER or the current user\n"
-//usage:     "\nOptions:"
 //usage:        IF_SELINUX(
 //usage:     "\n        -Z      Security context"
 //usage:        )
@@ -33,6 +50,15 @@
 //usage:       "$ id\n"
 //usage:       "uid=1000(andersen) gid=1000(andersen)\n"
 
+//usage:#define groups_trivial_usage
+//usage:       "[USER]"
+//usage:#define groups_full_usage "\n\n"
+//usage:       "Print the group memberships of USER or for the current process"
+//usage:
+//usage:#define groups_example_usage
+//usage:       "$ groups\n"
+//usage:       "andersen lp dialout cdrom floppy\n"
+
 #include "libbb.h"
 
 /* This is a NOEXEC applet. Be very careful! */
@@ -91,7 +117,7 @@ static int print_user(uid_t id, const char *prefix)
 
 /* On error set *n < 0 and return >= 0
  * If *n is too small, update it and return < 0
- *  (ok to trash groups[] in both cases)
+ * (ok to trash groups[] in both cases)
  * Otherwise fill in groups[] and return >= 0
  */
 static int get_groups(const char *username, gid_t rgid, gid_t *groups, int *n)
@@ -105,20 +131,19 @@ static int get_groups(const char *username, gid_t rgid, gid_t *groups, int *n)
                 m = getgrouplist(username, rgid, groups, n);
                 /* I guess *n < 0 might indicate error. Anyway,
                  * malloc'ing -1 bytes won't be good, so: */
-                //if (*n < 0)
-                //      return 0;
-                //return m;
-                //commented out here, happens below anyway
-        } else {
-                /* On error -1 is returned, which ends up in *n */
-                int nn = getgroups(*n, groups);
-                /* 0: nn <= *n, groups[] was big enough; -1 otherwise */
-                m = - (nn > *n);
-                *n = nn;
+                if (*n < 0)
+                        return 0;
+                return m;
         }
-        if (*n < 0)
-                return 0; /* error, don't return < 0! */
-        return m;
+
+        *n = getgroups(*n, groups);
+        if (*n >= 0)
+                return *n;
+        /* Error */
+        if (errno == EINVAL) /* *n is too small? */
+                *n = getgroups(0, groups); /* get needed *n */
+        /* if *n >= 0, return -1 (got new *n), else return 0 (error): */
+        return -(*n >= 0);
 }
 
 int id_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
@@ -136,11 +161,22 @@ int id_main(int argc UNUSED_PARAM, char **argv)
 #if ENABLE_SELINUX
         security_context_t scontext = NULL;
 #endif
-        /* Don't allow -n -r -nr -ug -rug -nug -rnug -uZ -gZ -GZ*/
-        /* Don't allow more than one username */
-        opt_complementary = "?1:u--g:g--u:G--u:u--G:g--G:G--g:r?ugG:n?ugG"
+
+        if (ENABLE_GROUPS && (!ENABLE_ID || applet_name[0] == 'g')) {
+                /* TODO: coreutils groups prepend "USER : " prefix,
+                 * and accept many usernames. Example:
+                 * # groups root root
+                 * root : root
+                 * root : root
+                 */
+                opt = option_mask32 = getopt32(argv, "") | JUST_ALL_GROUPS | NAME_NOT_NUMBER;
+        } else {
+                /* Don't allow -n -r -nr -ug -rug -nug -rnug -uZ -gZ -GZ*/
+                /* Don't allow more than one username */
+                opt_complementary = "?1:u--g:g--u:G--u:u--G:g--G:G--g:r?ugG:n?ugG"
                          IF_SELINUX(":u--Z:Z--u:g--Z:Z--g:G--Z:Z--G");
-        opt = getopt32(argv, "rnugG" IF_SELINUX("Z"));
+                opt = getopt32(argv, "rnugG" IF_SELINUX("Z"));
+        }
 
         username = argv[optind];
         if (username) {
@@ -177,11 +213,11 @@ int id_main(int argc UNUSED_PARAM, char **argv)
                 /* We are supplying largish buffer, trying
                  * to not run get_groups() twice. That might be slow
                  * ("user database in remote SQL server" case) */
-                groups = xmalloc(64 * sizeof(gid_t));
+                groups = xmalloc(64 * sizeof(groups[0]));
                 n = 64;
                 if (get_groups(username, rgid, groups, &n) < 0) {
                         /* Need bigger buffer after all */
-                        groups = xrealloc(groups, n * sizeof(gid_t));
+                        groups = xrealloc(groups, n * sizeof(groups[0]));
                         get_groups(username, rgid, groups, &n);
                 }
                 if (n > 0) {