Libpq free bug? (Was: [ODBC] IIS Postgres ASP ADO - Problem)

Forwarded to -bugs in case it gets missed.

This looks like it might be an issue to me, though I may well have
overlooked something in my brief look at the code.

Regards, Dave

-----Original Message-----
From: pgsql-odbc-owner@postgresql.org
[mailto:pgsql-odbc-owner@postgresql.org] On Behalf Of Marko Ristola
Sent: 01 August 2005 18:15
To: Joel Fradkin
Cc: 'James Dornan'; pgsql-odbc@postgresql.org
Subject: Re: [ODBC] IIS Postgres ASP ADO - Problem

I found a crashing problem during CONNECT into a database.

Here is the problem description:

Used Environment:
libpq-API under PostgreSQL 8.0.3
CVS HEAD of psqlodbc

libpq does have a problem with freeing memory, that has not
been alloced
with malloc()!

Here is the problem (I don't know, wether the PostgreSQL CVS
HEAD has a
fix for this):

postgresql-8.0.3/src/interfaces/libpq/fe-connect.c, function
conninfo_parse():

/* Make a working copy of PQconninfoOptions */
options = malloc(sizeof(PQconninfoOptions));
...
memcpy(options, PQconninfoOptions,
sizeof(PQconninfoOptions));

Unfortunately PQconninfoOptions[] contains only char*val
style pointers
instead of
char val[32] type character containers.
Because of this, the assumption, that memcpy() is enough to copy the
structure, is not
true anymore. You should NOT copy a static structure this way!

Working code would be something like this:

options = malloc(sizeof(PQconninfoOptions));
memcpy(options, PQconninfoOptions, sizeof(PQconninfoOptions));
for (i=0; PQconninfoOptions[i].val != NULL; i++) {
options[i].val = strdup(PQconninfoOptions[i].val);
... same for all other values
}
NULL termination.

Because of this, isql fails with me at the beginning, maybe because
dmalloc library, that I use for testing, discovered the problem.

Marko Ristola

Joel Fradkin wrote:

James,

The odbc is not working well for me (I can connect but get

intermittent

issues of the IIS server locking up in regards to connectivity).
My understanding is the snapshot version is the best odbc

out at this time.

Also can you connect via pgadmin (IE have the hba and config

files set to

allow external connections)?

My conection is not using dsn, but I did get dsn to work in testing.
My dsnless string is

Session("StringConn") =
"DRIVER={PostgreSQL};DATABASE=wazagua;SERVER=192.168.123.121;

PORT=5432;UID=p

ostgres;PWD=;ReadOnly=0;Protocol=6.4;FakeOidIndex=0;ShowOidCo

lumn=0;RowVersi

oning=0;ShowSystemTables=0;ConnSettings=;Fetch=100;Socket=409

6;UnknownSizes=

0;MaxVarcharSize=254;MaxLongVarcharSize=8190;Debug=0;CommLog=

0;Optimizer=1;K

sqo=1;UseDeclareFetch=0;TextAsLongVarchar=1;UnknownsAsLongVar

char=0;BoolsAsC

har=1;Parse=0;CancelAsFreeStmt=0;ExtraSysTablePrefixes=dd_;LF

Conversion=1;Up

datableCursors=1;DisallowPremature=0;TrueIsMinus1=0;BI=0;Byte

aAsLongVarBinar

y=0;UseServerSidePrepare=0"

My test using dsn used
Session("StringConn") ="DSN=postgresql;" & _
"UID=postgres;" & _
"PWD=;" & _
"Database=wazuni;"

asp code to use connection is :
dim Arec, Acmd, SQL ,AConn
set Arec = server.CreateObject("ADODB.Recordset")
Set AConn = Server.CreateObject("ADODB.CONNECTION")
set Acmd = server.CreateObject("ADODB.Command")
AConn.ConnectionTimeOut=30
AConn.commandtimeout=30
AConn.Open Session("StringConn")

For .net I use the npgsql .net objects.

Hope this helps you.

Joel Fradkin

-----Original Message-----
From: James Dornan [mailto:james@catch22.com]
Sent: Sunday, July 31, 2005 4:44 PM
To: jfradkin@wazagua.com
Subject: IIS Postgres ASP ADO - Problem

I noticed more than a few post from you about trying to

get Postgres

working with ODBC.
I'm hoping that maybe you would share some of that information. I am
running IIS under
windos 2003 server, and the latest(8.0.3) Postgres server on

the same

machine. I cannot
connect no matter what I do. I have tried everything.

The funny part is that I'm not new to ODBC, or windows.

I've worked

with windows all
the time, but just can't figure this one out. I've tried using a
connection string, a DSN,
reinstalling, IIS, Postgres, ODBC drivers, MDAC, Jet, and so

on. I still

have the same problem.
The odbc drive and it's dependant DDLs are in the path. The

permisions

are wide open
(for testing this specific problem).

Is there any insight you could shed on the dark world of

windows and

ODBC, where feed-
back is rare.

Thanks for any help you can provide.

-- James

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