Fix xundump's "value must match" check for split tables

The check applies to selectors with flag NSC_CONST set.  It permits
initializing them in new objects, but prevents changing them in
existing objects.  For split tables, initialization worked only in the
first part, because new objects were considered old in later parts.

For instance, in a custom config sect-chr with mnem in the second
part's field 2, new sector types were rejected with `Value for field 2
must be ""'.

diff --git a/src/lib/common/xundump.c b/src/lib/common/xundump.c
index 1f3dd404bdf87ad214afa2fa3ce2a1fa780a17a4..19c1ed7334ec537da1311e646327374749b8ea4c 100644 (file)
--- a/src/lib/common/xundump.c
+++ b/src/lib/common/xundump.c
@@ -70,7 +70,7 @@ static int cur_type;          /* Current table's file type */
 static int partno;             /* Counts from 0..#parts-1 */
 static void *cur_obj;          /* The object being read into */
 static int cur_id;             /* and its index in the table */
-static int cur_obj_is_blank;
+static int old_nelem;
 static unsigned char *idgap;   /* idgap && idgap[ID] iff part#0 lacks ID */
 static int idgap_max;          /* FIXME */
 
@@ -122,6 +122,7 @@ tbl_start(int type)
     partno = 0;
     cur_id = -1;
     cur_obj = NULL;
+    old_nelem = type == EF_BAD ? 0 : ef_nelem(type);
     idgap = NULL;
     idgap_max = 0;
 }
@@ -137,7 +138,7 @@ tbl_end(void)
 /*
  * Seek to current table's ID-th record.
  * ID must be acceptable.
- * Store it in cur_obj, and set cur_id and cur_obj_is_blank accordingly.
+ * Store it in cur_obj, and set cur_id accordingly.
  * Return 0 on success, -1 on failure.
  */
 static int
@@ -145,8 +146,6 @@ tbl_seek(int id)
 {
     struct empfile *ep = &empfile[cur_type];
 
-    cur_obj_is_blank = id >= ep->fids;
-
     if (id >= ef_nelem(cur_type)) {
        if (!ef_ensure_space(cur_type, id, 1))
            return gripe("Can't put ID %d into table %s", id, ep->name);
@@ -162,7 +161,7 @@ tbl_seek(int id)
 /*
  * Get the next object.
  * Must not have a record index.
- * Store it in cur_obj, and set cur_id and cur_obj_is_blank accordingly.
+ * Store it in cur_obj, and set cur_id accordingly.
  * Return 0 on success, -1 on failure.
  */
 static int
@@ -215,7 +214,7 @@ expected_id(int id1, int id2)
 
 /*
  * Get the next object, it has record index ID.
- * Store it in cur_obj, and set cur_id and cur_obj_is_blank accordingly.
+ * Store it in cur_obj, and set cur_id accordingly.
  * Ensure we're omitting the same objects as the previous parts.
  * Reset any omitted objects to default state.
  * Return 0 on success, -1 on failure.
@@ -663,7 +662,7 @@ fldval_must_match(int fldno)
      * it's for a const selector, unless the object is still blank, or
      * it was already given in a previous part of a split table.
      */
-    return (!cur_obj_is_blank && (fldca[fldno]->ca_flags & NSC_CONST))
+    return (cur_id < old_nelem && (fldca[fldno]->ca_flags & NSC_CONST))
        || fldidx[fldno] < cafldspp[i];
 }