pg_upgrade: throw an error for non-existent tablespace directories

Non-existent tablespace directory references can occur if user
tablespaces are created inside data directories and the data directory
is renamed in preparation for running pg_upgrade, and the symbolic links
are not updated.

Backpatch to 9.3.

diff --git a/contrib/pg_upgrade/tablespace.c b/contrib/pg_upgrade/tablespace.c
index 783ee93cfb6a6d4c2e13c165d6421d137b8ae9c6..94bba087bb7f8ecb4647b9dbc69f56d9db94e06a 100644 (file)
--- a/contrib/pg_upgrade/tablespace.c
+++ b/contrib/pg_upgrade/tablespace.c
@@ -11,6 +11,8 @@
 
 #include "pg_upgrade.h"
 
+#include <sys/types.h>
+
 static void get_tablespace_paths(void);
 static void set_tablespace_directory_suffix(ClusterInfo *cluster);
 
@@ -65,9 +67,39 @@ get_tablespace_paths(void)
    i_spclocation = PQfnumber(res, "spclocation");
 
    for (tblnum = 0; tblnum < os_info.num_old_tablespaces; tblnum++)
+   {
+       struct stat statBuf;
+
        os_info.old_tablespaces[tblnum] = pg_strdup(
                                     PQgetvalue(res, tblnum, i_spclocation));
 
+       /*
+        * Check that the tablespace path exists and is a directory.
+        * Effectively, this is checking only for tables/indexes in
+        * non-existent tablespace directories.  Databases located in
+        * non-existent tablespaces already throw a backend error.
+        * Non-existent tablespace directories can occur when a data
+        * directory that contains user tablespaces is moved as part
+        * of pg_upgrade preparation and the symbolic links are not
+        * updated.
+        */
+       if (stat(os_info.old_tablespaces[tblnum], &statBuf) != 0)
+       {
+           if (errno == ENOENT)
+               report_status(PG_FATAL,
+                             "tablespace directory \"%s\" does not exist\n",
+                             os_info.old_tablespaces[tblnum]);
+           else
+               report_status(PG_FATAL,
+                             "cannot stat() tablespace directory \"%s\": %s\n",
+                             os_info.old_tablespaces[tblnum], getErrorText(errno));
+       }
+       if (!S_ISDIR(statBuf.st_mode))
+               report_status(PG_FATAL,
+                             "tablespace path \"%s\" is not a directory\n",
+                             os_info.old_tablespaces[tblnum]);
+   }
+
    PQclear(res);
 
    PQfinish(conn);