Guard against createdb --location=PGDATA foo; without this, the code

tries to create a symlink pointing at itself.  Per trouble report from
Kenneth McDowell.

diff --git a/src/backend/commands/dbcommands.c b/src/backend/commands/dbcommands.c
index 92baacb72d50d09840c3e5e83511a24e366c9aa8..142fefb60fb868636f272cc35776a1874ba39e7e 100644 (file)
--- a/src/backend/commands/dbcommands.c
+++ b/src/backend/commands/dbcommands.c
@@ -9,7 +9,7 @@
  *
  *
  * IDENTIFICATION
- *       $Header: /cvsroot/pgsql/src/backend/commands/dbcommands.c,v 1.81 2001/10/25 05:49:24 momjian Exp $
+ *       $Header: /cvsroot/pgsql/src/backend/commands/dbcommands.c,v 1.82 2002/02/23 20:55:46 tgl Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -164,10 +164,21 @@ createdb(const char *dbname, const char *dbpath,
         * Compute nominal location (where we will try to access the
         * database), and resolve alternate physical location if one is
         * specified.
+        *
+        * If an alternate location is specified but is the same as the
+        * normal path, just drop the alternate-location spec (this seems
+        * friendlier than erroring out).  We must test this case to avoid
+        * creating a circular symlink below.
         */
        nominal_loc = GetDatabasePath(dboid);
        alt_loc = resolve_alt_dbpath(dbpath, dboid);
 
+       if (alt_loc && strcmp(alt_loc, nominal_loc) == 0)
+       {
+               alt_loc = NULL;
+               dbpath = NULL;
+       }
+
        if (strchr(nominal_loc, '\''))
                elog(ERROR, "database path may not contain single quotes");
        if (alt_loc && strchr(alt_loc, '\''))
@@ -198,7 +209,9 @@ createdb(const char *dbname, const char *dbpath,
        if (mkdir(target_dir, S_IRWXU) != 0)
                elog(ERROR, "CREATE DATABASE: unable to create database directory '%s': %m",
                         target_dir);
-       rmdir(target_dir);
+       if (rmdir(target_dir) != 0)
+               elog(ERROR, "CREATE DATABASE: unable to remove temp directory '%s': %m",
+                        target_dir);
 
        /* Make the symlink, if needed */
        if (alt_loc)
@@ -548,6 +561,9 @@ resolve_alt_dbpath(const char *dbpath, Oid dboid)
        }
 
        len = strlen(prefix) + 6 + sizeof(Oid) * 8 + 1;
+       if (len >= MAXPGPATH - 100)
+               elog(ERROR, "Alternate path is too long");
+
        ret = palloc(len);
        snprintf(ret, len, "%s/base/%u", prefix, dboid);