Add filename check in file_fdw_validator.

This fix is based on Albe's "Bug in SQL/MED?" patch.
Error reporting in fileGetOptions() is also degrated to elog().
Per comment from Alvaro Herrera.

diff --git a/contrib/file_fdw/file_fdw.c b/contrib/file_fdw/file_fdw.c
index 466c015107db28b46601b759ad4542d6589a597c..bf805687806cc44e5d96304c88935d2fcfa845d0 100644 (file)
--- a/contrib/file_fdw/file_fdw.c
+++ b/contrib/file_fdw/file_fdw.c
@@ -215,6 +215,17 @@ file_fdw_validator(PG_FUNCTION_ARGS)
     */
    ProcessCopyOptions(NULL, true, other_options);
 
+   /*
+    * Filename is required for file_fdw foreign tables.  We must validate it
+    * separately because ProcessCopyOptions() doesn't validate it.
+    * We don't care whether the value is empty or not, because COPY doesn't
+    * care that.
+    */
+   if (catalog == ForeignTableRelationId && filename == NULL)
+       ereport(ERROR,
+               (errcode(ERRCODE_FDW_UNABLE_TO_CREATE_REPLY),
+                errmsg("filename is required for file_fdw foreign tables")));
+
    PG_RETURN_VOID();
 }
 
@@ -286,10 +297,15 @@ fileGetOptions(Oid foreigntableid,
        }
        prev = lc;
    }
+
+   /*
+    * The requirement of filename option must have been checked by
+    * file_fdw_validator at every DDL.  We check it here again just in case
+    * to avoid crash caused by unexpected catalog corruption.
+    */
    if (*filename == NULL)
-       ereport(ERROR,
-               (errcode(ERRCODE_FDW_UNABLE_TO_CREATE_REPLY),
-                errmsg("filename is required for file_fdw foreign tables")));
+       elog(ERROR, "filename is required for file_fdw foreign tables");
+
    *other_options = options;
 }