Make password null on startup.

src/backend/commands/user.c

@@ -152,11 +152,14 @@ void DefineUser(CreateUserStmt *stmt) {
   /* Add the stuff here for groups.
    */
 
+  UpdatePgPwdFile(sql);
+
+  /* This goes after the UpdatePgPwdFile to be certain that two backends to not
+   * attempt to write to the pg_pwd file at the same time.
+   */
   RelationUnsetLockForWrite(pg_user_rel);
   heap_close(pg_user_rel);
 
-  UpdatePgPwdFile(sql);
-
   if (IsTransactionBlock() && !inblock)
     EndTransactionBlock();
 }
@@ -195,6 +198,10 @@ extern void AlterUser(AlterUserStmt *stmt) {
    */
   pg_user_rel = heap_openr(UserRelationName);
   pg_user_dsc = RelationGetTupleDescriptor(pg_user_rel);
+  /* Secure a write lock on pg_user so we can be sure that when the dump of
+   * the pg_pwd file is done, there is not another backend doing the same.
+   */
+  RelationSetLockForWrite(pg_user_rel);
 
   scan = heap_beginscan(pg_user_rel, false, false, 0, NULL);
   while (HeapTupleIsValid(tuple = heap_getnext(scan, 0, &buffer))) {
@@ -207,9 +214,10 @@ extern void AlterUser(AlterUserStmt *stmt) {
     }
   }
   heap_endscan(scan);
-  heap_close(pg_user_rel);
 
   if (!exists) {
+    RelationUnsetLockForWrite(pg_user_rel);
+    heap_close(pg_user_rel);
     UserAbortTransactionBlock();
     elog(WARN, "alterUser: user \"%s\" does not exist", stmt->user);
     return;
@@ -257,6 +265,9 @@ extern void AlterUser(AlterUserStmt *stmt) {
 
   UpdatePgPwdFile(sql);
 
+  RelationUnsetLockForWrite(pg_user_rel);
+  heap_close(pg_user_rel);
+
   if (IsTransactionBlock() && !inblock)
     EndTransactionBlock();
 }
@@ -265,7 +276,8 @@ extern void AlterUser(AlterUserStmt *stmt) {
 extern void RemoveUser(char* user) {
 
   char*            pg_user;
-  Relation         pg_rel;
+  Relation         pg_user_rel,
+                   pg_rel;
   TupleDesc        pg_dsc;
   HeapScanDesc     scan;
   HeapTuple        tuple;
@@ -295,10 +307,14 @@ extern void RemoveUser(char* user) {
   /* Perform a scan of the pg_user relation to find the usesysid of the user to
    * be deleted.  If it is not found, then return a warning message.
    */
-  pg_rel = heap_openr(UserRelationName);
-  pg_dsc = RelationGetTupleDescriptor(pg_rel);
+  pg_user_rel = heap_openr(UserRelationName);
+  pg_dsc = RelationGetTupleDescriptor(pg_user_rel);
+  /* Secure a write lock on pg_user so we can be sure that when the dump of
+   * the pg_pwd file is done, there is not another backend doing the same.
+   */
+  RelationSetLockForWrite(pg_user_rel);
 
-  scan = heap_beginscan(pg_rel, false, false, 0, NULL);
+  scan = heap_beginscan(pg_user_rel, false, false, 0, NULL);
   while (HeapTupleIsValid(tuple = heap_getnext(scan, 0, &buffer))) {
     datum = heap_getattr(tuple, buffer, Anum_pg_user_usename, pg_dsc, &n);
 
@@ -310,9 +326,10 @@ extern void RemoveUser(char* user) {
     ReleaseBuffer(buffer);
   }
   heap_endscan(scan);
-  heap_close(pg_rel);
 
   if (usesysid == -1) {
+    RelationUnsetLockForWrite(pg_user_rel);
+    heap_close(pg_user_rel);
     UserAbortTransactionBlock();
     elog(WARN, "removeUser: user \"%s\" does not exist", user);
     return;
@@ -373,6 +390,9 @@ extern void RemoveUser(char* user) {
 
   UpdatePgPwdFile(sql);
 
+  RelationUnsetLockForWrite(pg_user_rel);
+  heap_close(pg_user_rel);
+
   if (IsTransactionBlock() && !inblock)
     EndTransactionBlock();
 }

src/backend/libpq/be-pqexec.c

@@ -8,7 +8,7 @@
  *
  *
  * IDENTIFICATION
- *	  $Header: /cvsroot/pgsql/src/backend/libpq/Attic/be-pqexec.c,v 1.10 1997/12/06 22:56:35 momjian Exp $
+ *	  $Header: /cvsroot/pgsql/src/backend/libpq/Attic/be-pqexec.c,v 1.11 1997/12/12 16:26:14 momjian Exp $
  *
  *-------------------------------------------------------------------------
  */
@@ -143,11 +143,11 @@ PQexec(char *query)
 	be_portalpush(entry);
 
 	/* ----------------
-	 *	pg_eval_dest will put the query results in a portal which will
+	 *	pg_exec_query_dest will put the query results in a portal which will
 	 *	end up on the top of the portal stack.
 	 * ----------------
 	 */
-	pg_eval_dest(query, (char **) NULL, (Oid *) NULL, 0, Local);
+	pg_exec_query_dest(query, (char **) NULL, (Oid *) NULL, 0, Local);
 
 	/* ----------------
 	 *	pop the portal off the portal stack and return the

src/backend/libpq/crypt.c

@@ -17,6 +17,7 @@
 #endif
 
 #include "postgres.h"
+#include "miscadmin.h"
 #include "libpq/crypt.h"
 #include "utils/nabstime.h"
 #include "utils/palloc.h"
@@ -129,7 +130,7 @@ MsgType crypt_salt(const char* user) {
 
   crypt_getloginfo(user, &passwd, &valuntil);
 
-  if (passwd == NULL || *passwd == '\0') {
+  if (passwd == NULL || *passwd == '\0' || !strcmp(passwd, "\\N")) {
     if (passwd) pfree((void*)passwd);
     if (valuntil) pfree((void*)valuntil);
     return STARTUP_UNSALT_MSG;

src/include/catalog/pg_user.h

@@ -7,7 +7,7 @@
  *
  * Copyright (c) 1994, Regents of the University of California
  *
- * $Id: pg_user.h,v 1.7 1997/12/09 03:11:25 scrappy Exp $
+ * $Id: pg_user.h,v 1.8 1997/12/12 16:26:36 momjian Exp $
  *
  * NOTES
  *	  the genbki.sh script reads this file and generates .bki
@@ -65,7 +65,7 @@ typedef FormData_pg_user *Form_pg_user;
  *		initial contents of pg_user
  * ----------------
  */
-DATA(insert OID = 0 ( postgres PGUID t t t t "" 2116994400 ));
+DATA(insert OID = 0 ( postgres PGUID t t t t _null_ 2116994400 ));
 
 BKI_BEGIN
 #ifdef ALLOW_PG_GROUP