Index: src/interfaces/libpq/fe-connect.c
===================================================================
RCS file: /cvsroot/pgsql/src/interfaces/libpq/fe-connect.c,v
retrieving revision 1.389
diff -c -c -r1.389 fe-connect.c
*** src/interfaces/libpq/fe-connect.c	3 Mar 2010 20:31:09 -0000	1.389
--- src/interfaces/libpq/fe-connect.c	11 Mar 2010 00:53:00 -0000
***************
*** 71,76 ****
--- 71,78 ----
  
  #include "libpq/ip.h"
  #include "mb/pg_wchar.h"
+ #include "utils/elog.h"
+ #include "utils/errcodes.h"
  
  #ifndef FD_CLOEXEC
  #define FD_CLOEXEC 1
***************
*** 284,289 ****
--- 286,292 ----
  static char *pwdfMatchesString(char *buf, char *token);
  static char *PasswordFromFile(char *hostname, char *port, char *dbname,
  				 char *username);
+ static void dot_pg_pass_warning(PGconn *conn);
  static void default_threadlock(int acquire);
  
  
***************
*** 652,657 ****
--- 655,662 ----
  										conn->dbName, conn->pguser);
  		if (conn->pgpass == NULL)
  			conn->pgpass = strdup(DefaultPassword);
+ 		else
+ 			conn->dot_pgpass_used = true;
  	}
  
  	/*
***************
*** 2133,2138 ****
--- 2138,2145 ----
  
  error_return:
  
+ 	dot_pg_pass_warning(conn);
+ 	
  	/*
  	 * We used to close the socket at this point, but that makes it awkward
  	 * for those above us if they wish to remove this socket from their own
***************
*** 2191,2196 ****
--- 2198,2204 ----
  	conn->verbosity = PQERRORS_DEFAULT;
  	conn->sock = -1;
  	conn->password_needed = false;
+ 	conn->dot_pgpass_used = false;
  #ifdef USE_SSL
  	conn->allow_ssl_try = true;
  	conn->wait_ssl_try = false;
***************
*** 4426,4431 ****
--- 4434,4471 ----
  #undef LINELEN
  }
  
+ 
+ /*
+  *	If the connection failed, we should mention if
+  *	we got the password from .pgpass in case that
+  *	password is wrong.
+  */
+ static void
+ dot_pg_pass_warning(PGconn *conn)
+ {
+ 	int invalid_authorization_specification_integer = 0;
+ 	int i;
+ 
+ 	if (!conn->dot_pgpass_used || !conn->password_needed)
+ 		return;	 /* quick exit */
+ 	
+ 	/* Convert 6-bit packed sqlstate to a base-10 integer */
+ 	for (i = 0; i < 5; i++)
+ 	{
+ 		invalid_authorization_specification_integer *= 10;
+ 		invalid_authorization_specification_integer +=
+ 			(ERRCODE_INVALID_AUTHORIZATION_SPECIFICATION >> (i * 6)) & 0x3F;
+ 	}
+ 
+ 	/* If it was 'invalid authorization', add .pgpass mention */
+ 	if (conn->result &&
+ 		atoi(PQresultErrorField(conn->result, PG_DIAG_SQLSTATE)) ==
+ 			invalid_authorization_specification_integer)
+ 		appendPQExpBufferStr(&conn->errorMessage,
+ 			libpq_gettext("password retrieved from .pgpass\n"));
+ }
+ 
+ 	
  /*
   * Obtain user's home directory, return in given buffer
   *
Index: src/interfaces/libpq/libpq-int.h
===================================================================
RCS file: /cvsroot/pgsql/src/interfaces/libpq/libpq-int.h,v
retrieving revision 1.149
diff -c -c -r1.149 libpq-int.h
*** src/interfaces/libpq/libpq-int.h	26 Feb 2010 02:01:33 -0000	1.149
--- src/interfaces/libpq/libpq-int.h	11 Mar 2010 00:53:00 -0000
***************
*** 343,348 ****
--- 343,349 ----
  	ProtocolVersion pversion;	/* FE/BE protocol version in use */
  	int			sversion;		/* server version, e.g. 70401 for 7.4.1 */
  	bool		password_needed;	/* true if server demanded a password */
+ 	bool		dot_pgpass_used;	/* true if used .pgpass */
  	bool		sigpipe_so;		/* have we masked SIGPIPE via SO_NOSIGPIPE? */
  	bool		sigpipe_flag;	/* can we mask SIGPIPE via MSG_NOSIGNAL? */