Re: OpenLDAP API -- ldap_unbind SIGPIPE

[Igor Brezac <igor@ipass.net>]

Kervin,

I do not think that this is a bug because the socket can brake between the
test and the write() call.  I tried several different ldap libs and they
behave the same in this particular example.  The application needs to take
care of this with something simple like signal(SIGPIPE, SIG_IGN).

-Igor

On Wed, 3 Apr 2002, Kervin Pierre wrote:

> hi,
>
> Thanks for the follow-up.
>
> I think this is a bug.  The ldap_unbind code should check that the
> socket is still writeable before trying to write to it ( maybe using
> fstat(2) ??)
>
> --Kervin
>
>
> Igor Brezac wrote:
> > Pierre,
> >
> > I figured it out.  The os is raising SIGPIPE (write() to a broken socket)
> > and by default it terminates the program.  I just needed to ignore the
> > signal or write a special handler for it.  Thanks for you help...
> >
> > -Igor
> >
> > On Tue, 2 Apr 2002, Igor Brezac wrote:
> >
> >
> >>I do not have gdb, but adb is available.  I do not get core dump in this
> >>example.  The following is the output:
> >>
> >># ./a.out
> >>ldap_search_st() error Can't contact LDAP server
> >>Broken Pipe
> >>
> >>I do not expect "Broken Pipe".  I traced it to ldap_send_unbind()
> >>call in libldap.so.
> >>
> >>I added
> >>debug = 0x00028;
> >>ldap_set_option(NULL, LDAP_OPT_DEBUG_LEVEL, &(debug));
> >>after ldap_initialize() call and I get the following output.
> >>
> >># ./a.out
> >>request 1 done
> >>ber_get_next failed.
> >>LDAP: Can't contact LDAP server
> >>Broken Pipe
> >>
> >>I hope that this will help.
> >>
> >>-Igor
> >>
> >>On Tue, 2 Apr 2002, Kervin Pierre wrote:
> >>
> >>
> >>>Do you have gdb installed? How about a full backtrace on the core file.
> >>>
> >>>Igor Brezac wrote:
> >>>
> >>>>Hello,
> >>>>
> >>>>I tried to send this message to openldap-software, but I did not have
> >>>>much luck there.  So, maybe some of you guys may be able to help me.
> >>>>
> >>>>I use Solaris 8 and openldap 2.0.23.  The following short program crashes
> >>>>on the ldap_unbind() call.  I tried various different versions of this
> >>>>program without success.  Am I doing something wrong here?
> >>>>
> >>>>Your help will be greatly appreciated.
> >>>>
> >>>>-Igor
> >>>>
> >>>>#include        <sys/types.h>
> >>>>#include        <stdlib.h>
> >>>>
> >>>>#include        <lber.h>
> >>>>#include        <ldap.h>
> >>>>
> >>>>int main() {
> >>>>
> >>>>        int rc;
> >>>>        LDAP   *ldi;
> >>>>        struct timeval tv;
> >>>>        LDAPMessage *res = NULL;
> >>>>        LDAPMessage *msg = NULL;
> >>>>        char *dn;
> >>>>        char *server = "ldap://10.1.1.197/";;
> >>>>        char *base_dn = "o=pb";
> >>>>        char *filter = "uid=igor";
> >>>>        char *attrs[] = {"dn",NULL};
> >>>>
> >>>>
> >>>>        rc = ldap_initialize(&ldi, server);
> >>>>        if (rc != LDAP_SUCCESS) {
> >>>>                exit (2);
> >>>>        }
> >>>>
> >>>>        rc = ldap_simple_bind_s(ldi, "", "");
> >>>>        if (rc != LDAP_SUCCESS) {
> >>>>                exit (2);
> >>>>        }
> >>>>
> >>>>//  If the ldap server is no longer available at this point
> >>>>
> >>>>        tv.tv_sec = 5;
> >>>>        tv.tv_usec = 0;
> >>>>        rc = ldap_search_st(ldi, base_dn, LDAP_SCOPE_SUBTREE, filter,
> >>>>                        (char **) attrs, 0, &tv, &res);
> >>>>
> >>>>        if (rc != LDAP_SUCCESS) {
> >>>>                ldap_get_option(ldi, LDAP_OPT_ERROR_NUMBER, &rc);
> >>>>                printf("ldap_search_st() error %s\n", ldap_err2string(rc));
> >>>>                ldap_msgfree(res);
> >>>>                ldap_unbind(ldi);
> >>>>
> >>>>// ldap_unbind will cause a dump here
> >>>>
> >>>>                exit(2);
> >>>>        }
> >>>>
> >>>>        msg = ldap_first_entry(ldi, res);
> >>>>        dn = ldap_get_dn(ldi, msg);
> >>>>        printf("DN: %s\n", dn);
> >>>>
> >>>>        ldap_msgfree(msg);
> >>>>        free(dn);
> >>>>        ldap_unbind_s(ldi);
> >>>>        exit (1);
> >>>>}
> >>>>
> >>>>
> >>>>
> >>>>
> >>>>
> >>>
> >>>
> >>>
> >>>
> >>
> >
> >
> >
>
>
>
>