Merge pull request #8058 from keszybz/sysusers-inline

Extend sysusers for package installation scripts

src/basic/conf-files.c

@@ -154,6 +154,70 @@ static int conf_files_list_strv_internal(char ***strv, const char *suffix, const
         return 0;
 }
 
+int conf_files_insert(char ***strv, const char *root, const char *dirs, const char *path) {
+        /* Insert a path into strv, at the place honouring the usual sorting rules:
+         * - we first compare by the basename
+         * - and then we compare by dirname, allowing just one file with the given
+         *   basename.
+         * This means that we will
+         * - add a new entry if basename(path) was not on the list,
+         * - do nothing if an entry with higher priority was already present,
+         * - do nothing if our new entry matches the existing entry,
+         * - replace the existing entry if our new entry has higher priority.
+         */
+        char *t;
+        unsigned i;
+        int r;
+
+        for (i = 0; i < strv_length(*strv); i++) {
+                int c;
+
+                c = base_cmp(*strv + i, &path);
+                if (c == 0) {
+                        const char *dir;
+
+                        /* Oh, we found our spot and it already contains something. */
+                        NULSTR_FOREACH(dir, dirs) {
+                                char *p1, *p2;
+
+                                p1 = path_startswith((*strv)[i], root);
+                                if (p1)
+                                        /* Skip "/" in dir, because p1 is without "/" too */
+                                        p1 = path_startswith(p1, dir + 1);
+                                if (p1)
+                                        /* Existing entry with higher priority
+                                         * or same priority, no need to do anything. */
+                                        return 0;
+
+                                p2 = path_startswith(path, dir);
+                                if (p2) {
+                                        /* Our new entry has higher priority */
+                                        t = path_join(root, path, NULL);
+                                        if (!t)
+                                                return log_oom();
+
+                                        return free_and_replace((*strv)[i], t);
+                                }
+                        }
+
+                } else if (c > 0)
+                        /* Following files have lower priority, let's go insert our
+                         * new entry. */
+                        break;
+
+                /* … we are not there yet, let's continue */
+        }
+
+        t = path_join(root, path, NULL);
+        if (!t)
+                return log_oom();
+
+        r = strv_insert(strv, i, t);
+        if (r < 0)
+                free(t);
+        return r;
+}
+
 int conf_files_list_strv(char ***strv, const char *suffix, const char *root, unsigned flags, const char* const* dirs) {
         _cleanup_strv_free_ char **copy = NULL;
 

src/basic/conf-files.h

@@ -28,3 +28,4 @@ enum {
 int conf_files_list(char ***ret, const char *suffix, const char *root, unsigned flags, const char *dir, ...);
 int conf_files_list_strv(char ***ret, const char *suffix, const char *root, unsigned flags, const char* const* dirs);
 int conf_files_list_nulstr(char ***ret, const char *suffix, const char *root, unsigned flags, const char *dirs);
+int conf_files_insert(char ***strv, const char *root, const char *dirs, const char *path);

src/basic/strv.c

@@ -446,7 +446,7 @@ int strv_push_pair(char ***l, char *a, char *b) {
         return 0;
 }
 
-int strv_push_prepend(char ***l, char *value) {
+int strv_insert(char ***l, unsigned position, char *value) {
         char **c;
         unsigned n, m, i;
 
@@ -454,6 +454,7 @@ int strv_push_prepend(char ***l, char *value) {
                 return 0;
 
         n = strv_length(*l);
+        position = MIN(position, n);
 
         /* increase and check for overflow */
         m = n + 2;
@@ -464,10 +465,12 @@ int strv_push_prepend(char ***l, char *value) {
         if (!c)
                 return -ENOMEM;
 
-        for (i = 0; i < n; i++)
+        for (i = 0; i < position; i++)
+                c[i] = (*l)[i];
+        c[position] = value;
+        for (i = position; i < n; i++)
                 c[i+1] = (*l)[i];
 
-        c[0] = value;
         c[n+1] = NULL;
 
         free(*l);

src/basic/strv.h

@@ -54,7 +54,12 @@ int strv_extendf(char ***l, const char *format, ...) _printf_(2,0);
 int strv_extend_front(char ***l, const char *value);
 int strv_push(char ***l, char *value);
 int strv_push_pair(char ***l, char *a, char *b);
-int strv_push_prepend(char ***l, char *value);
+int strv_insert(char ***l, unsigned position, char *value);
+
+static inline int strv_push_prepend(char ***l, char *value) {
+        return strv_insert(l, 0, value);
+}
+
 int strv_consume(char ***l, char *value);
 int strv_consume_pair(char ***l, char *a, char *b);
 int strv_consume_prepend(char ***l, char *value);

src/basic/user-util.c

@@ -553,18 +553,18 @@ int take_etc_passwd_lock(const char *root) {
          * awfully racy, and thus we just won't do them. */
 
         if (root)
-                path = prefix_roota(root, "/etc/.pwd.lock");
+                path = prefix_roota(root, ETC_PASSWD_LOCK_PATH);
         else
-                path = "/etc/.pwd.lock";
+                path = ETC_PASSWD_LOCK_PATH;
 
         fd = open(path, O_WRONLY|O_CREAT|O_CLOEXEC|O_NOCTTY|O_NOFOLLOW, 0600);
         if (fd < 0)
-                return -errno;
+                return log_debug_errno(errno, "Cannot open %s: %m", path);
 
         r = fcntl(fd, F_SETLKW, &flock);
         if (r < 0) {
                 safe_close(fd);
-                return -errno;
+                return log_debug_errno(errno, "Locking %s failed: %m", path);
         }
 
         return fd;
@@ -645,6 +645,8 @@ bool valid_gecos(const char *d) {
 }
 
 bool valid_home(const char *p) {
+        /* Note that this function is also called by valid_shell(), any
+         * changes must account for that. */
 
         if (isempty(p))
                 return false;

src/basic/user-util.h

@@ -63,6 +63,8 @@ int take_etc_passwd_lock(const char *root);
 #define UID_NOBODY ((uid_t) 65534U)
 #define GID_NOBODY ((gid_t) 65534U)
 
+#define ETC_PASSWD_LOCK_PATH "/etc/.pwd.lock"
+
 static inline bool uid_is_dynamic(uid_t uid) {
         return DYNAMIC_UID_MIN <= uid && uid <= DYNAMIC_UID_MAX;
 }
@@ -96,6 +98,15 @@ bool valid_user_group_name_or_id(const char *u);
 bool valid_gecos(const char *d);
 bool valid_home(const char *p);
 
+static inline bool valid_shell(const char *p) {
+        /* We have the same requirements, so just piggy-back on the home check.
+         *
+         * Let's ignore /etc/shells because this is only applicable to real and
+         * not system users. It is also incompatible with the idea of empty /etc.
+         */
+        return valid_home(p);
+}
+
 int maybe_setgroups(size_t size, const gid_t *list);
 
 bool synthesize_nobody(void);