Provide a default single-user entry in init mode

This complements 6aac230c. The entry is created unless
a component for runlevel S already exists.

* src/comp.c (component_foreach): New function.
* src/pies.h: Likewise.
* src/sysvinit.c (inittab_parse): Provide default S
entry unless one is already defined.

3 files changed, 29 insertions, 4 deletions

diff --git a/src/comp.c b/src/comp.c
index 38e440e..43772c2 100644
--- a/src/comp.c
+++ b/src/comp.c
@@ -812,6 +812,23 @@ component_depmap_next (pies_depmap_pos_t pos)
     return NULL;
   return comp_array[n];
 }
+
+int
+component_foreach (int (*filter) (struct component *, void *), void *data)
+{
+  struct component *comp;
+  int rc = 0;
+  struct complist *list = &comp_list[cur];
+
+  for (comp = list->head; comp; )
+    {
+      struct component *next = comp->next;
+      if ((rc = filter (comp, data)) != 0)
+        break;
+      comp = next;
+    }
+  return rc;
+}
 
 
 
diff --git a/src/pies.h b/src/pies.h
index 939bd4c..d4b5c6a 100644
--- a/src/pies.h
+++ b/src/pies.h
@@ -406,6 +406,8 @@ int component_is_active (struct component *comp);
 
 void component_finish (struct component *comp, grecs_locus_t *locus);
 struct grecs_keyword *find_component_keyword (const char *ident);
+int component_foreach (int (*filter) (struct component *, void *),
+                       void *data);
 
 void components_dump_depmap (void);
 void components_trace (char **argv, enum pies_depmap_direction dir);
diff --git a/src/sysvinit.c b/src/sysvinit.c
index 695a22a..cc26fa9 100644
--- a/src/sysvinit.c
+++ b/src/sysvinit.c
@@ -1092,6 +1092,13 @@ inittab_parse_line (struct inittab_ctx *ctx)
   return inittab_ok;
 }
 
+/* Return true if we hit a single-user component */
+static int
+is_single_user (struct component *comp, void *data)
+{
+  return is_sysvinit (comp) && comp->runlevels && strchr (comp->runlevels, 'S');
+}
+
 int
 inittab_parse (const char *file)
 {
@@ -1125,13 +1132,12 @@ inittab_parse (const char *file)
       err = 1;
     }
 
-  if (component_list_is_empty ())
+  if (!component_foreach (is_single_user, 0))
     {
-      /* Provide default inittab entry */
+      /* Provide single-user entry */
       ctx.file = __FILE__;
       ctx.line_no = __LINE__;
-      grecs_asprintf (&ctx.buf, &ctx.size, "~~:%s:wait:%s\n",
-                      valid_runlevels, emergency_shell);
+      grecs_asprintf (&ctx.buf, &ctx.size, "~~:S:wait:%s\n", emergency_shell);
       inittab_parse_line (&ctx);
     }