Do not fail password check if shadow password does not exist -

fall back to ordinary one

Reduced usage of functions returning datain static buffers.
(mostly passwd/group/shadow related):

function                                             old     new   delta
correct_password                                     143     193     +50
sulogin_main                                         490     533     +43
adduser_main                                         732     774     +42
passwd_main                                         1875    1915     +40
addgroup_main                                        330     365     +35
bb_internal_getspnam                                  38       -     -38
bb_internal_fgetpwent                                 38       -     -38
bb_internal_fgetgrent                                 38       -     -38
static.resultbuf                                     168      88     -80
static.buffer                                       1872    1104    -768
------------------------------------------------------------------------------
(add/remove: 0/3 grow/shrink: 5/2 up/down: 210/-962)         Total: -752 bytes

1 files changed, 24 insertions, 21 deletions

diff --git a/loginutils/addgroup.c b/loginutils/addgroup.c
index 768d2c061..78250a418 100644
--- a/loginutils/addgroup.c
+++ b/loginutils/addgroup.c
@@ -15,35 +15,37 @@
  * return 1 on failure */
 static int group_study(struct group *g)
 {
+        enum { max = 65000 };
         FILE *etc_group;
         gid_t desired;
-
-        struct group *grp;
-        const int max = 65000;
+        /* Using _r function to avoid static buffers pulled in */
+        char buffer[256];
+        struct group grp;
+        struct group *result;
 
         etc_group = xfopen(bb_path_group_file, "r");
 
         /* make sure gr_name isn't taken, make sure gid is kosher */
         desired = g->gr_gid;
-        while ((grp = fgetgrent(etc_group))) {
-                if ((strcmp(grp->gr_name, g->gr_name)) == 0) {
+        while (!fgetgrent_r(etc_group, &grp, buffer, sizeof(buffer), &result)) {
+                if ((strcmp(grp.gr_name, g->gr_name)) == 0) {
                         bb_error_msg_and_die("%s: group already in use", g->gr_name);
                 }
-                if ((desired) && grp->gr_gid == desired) {
+                if ((desired) && grp.gr_gid == desired) {
                         bb_error_msg_and_die("%d: gid already in use",
                                                           desired);
                 }
-                if ((grp->gr_gid > g->gr_gid) && (grp->gr_gid < max)) {
-                        g->gr_gid = grp->gr_gid;
+                if ((grp.gr_gid > g->gr_gid) && (grp.gr_gid < max)) {
+                        g->gr_gid = grp.gr_gid;
                 }
         }
-        fclose(etc_group);
+        if (ENABLE_FEATURE_CLEAN_UP)
+                fclose(etc_group);
 
         /* gid */
+        g->gr_gid++;
         if (desired) {
                 g->gr_gid = desired;
-        } else {
-                g->gr_gid++;
         }
         /* return 1; */
         return 0;
@@ -65,12 +67,16 @@ static int addgroup(char *group, gid_t gid, const char *user)
         file = xfopen(bb_path_group_file, "a");
         /* group:passwd:gid:userlist */
         fprintf(file, "%s:%s:%d:%s\n", group, "x", gr.gr_gid, user);
-        fclose(file);
+        if (ENABLE_FEATURE_CLEAN_UP)
+                fclose(file);
 
 #if ENABLE_FEATURE_SHADOWPASSWDS
-        file = xfopen(bb_path_gshadow_file, "a");
-        fprintf(file, "%s:!::\n", group);
-        fclose(file);
+        file = fopen_or_warn(bb_path_gshadow_file, "a");
+        if (file) {
+                fprintf(file, "%s:!::\n", group);
+                if (ENABLE_FEATURE_CLEAN_UP)
+                        fclose(file);
+        }
 #endif
 
         /* return 1; */
@@ -80,10 +86,8 @@ static int addgroup(char *group, gid_t gid, const char *user)
 /*
  * addgroup will take a login_name as its first parameter.
  *
- * gid
- *
- * can be customized via command-line parameters.
- * ________________________________________________________________________ */
+ * gid can be customized via command-line parameters.
+ */
 int addgroup_main(int argc, char **argv);
 int addgroup_main(int argc, char **argv)
 {
@@ -103,6 +107,5 @@ int addgroup_main(int argc, char **argv)
                 bb_error_msg_and_die(bb_msg_perm_denied_are_you_root);
         }
 
-        /* werk */
-        return addgroup(argv[0], gid, (argv[1]) ? argv[1] : "");
+        return addgroup(argv[0], gid, argv[1] ? argv[1] : "");
 }