Bus Error?

[Brian Postow]

Sorry for the post spam....

I'm trying to test t38modem on my mac, and I get a bus error. GDB gives the following stack trace:

(gdb) run -p ttyx0
Starting program: /Users/acordex/Documents/projects/t38modem/t38modem/t38modem -p ttyx0
Reading symbols for shared libraries +++++++++++++++........................... done
T38Modem Version 1.1.0
(H323plus-1.20.2, PWLIB-1.12.0) by Vyacheslav Frolov on Unix Darwin (9.6.0-i386)

2009/03/11 17:27:22.431        T38Modem        Version 1.1.0 by Vyacheslav Frolov on Unix Darwin (9.6.0-i386) at 2009/3/11 17:27:22.431
Reading symbols for shared libraries . done
Reading symbols for shared libraries . done
Reading symbols for shared libraries . done
Reading symbols for shared libraries . done

Program received signal EXC_BAD_ACCESS, Could not access memory.
Reason: KERN_PROTECTION_FAILURE at address: 0x0000003c
0x00fd79ba in PString::operator= ()
(gdb) where
#0  0x00fd79ba in PString::operator= ()
#1  0x00025225 in PseudoModemPty::PseudoModemPty ()
#2  0x000079f9 in CreatePseudoModemPty ()
#3  0x00007ab9 in PseudoModemDrivers::CreateModem ()
#4  0x00003ed7 in PseudoModemQ::CreateModem ()
#5  0x0002bf9d in MyH323EndPoint::Initialise ()
#6  0x0002da7c in MyH323EndPoint::Create ()
#7  0x00027ccb in T38Modem::Initialise ()
#8  0x000280bd in T38Modem::Main ()
#9  0x00fbe8b2 in PProcess::_main ()
#10 0x00026f97 in main ()
(gdb)

I'm not sure whether it's a bug, or I didn't set something up correctly.

This is on a mac running OSX 10.5, in case that matters.

thanks.

[Vyacheslav Frolov]

Try to replace line 328 of drv_pty.cxx:

    ptyname = &ptypath[5];

by

    ptyname = ptypath.Mid(5);

If it's not help then build with debug info and gdb it.

[Brian Postow]

Yes, that works! thanks

[Brian Postow]

warning: Could not find object file "/sw/src/fink.build/expat-1.95.8-2/expat-1.95.8/lib/xmlparse.lo" - no debug information available for "lib/xmlparse.c".

warning: Could not find object file "/sw/src/fink.build/expat-1.95.8-2/expat-1.95.8/lib/xmltok.lo" - no debug information available for "lib/xmltok.c".

warning: Could not find object file "/sw/src/fink.build/expat-1.95.8-2/expat-1.95.8/lib/xmlrole.lo" - no debug information available for "lib/xmlrole.c".

........ done

(gdb) run -n -o trace.log -p ttyx0,ttyx1 --old-asn --route 0@127.0.0.1 --route all@192.168.90.54
Starting program: /Users/acordex/Documents/projects/t38modem/t38modem/t38modem -n -o trace.log -p ttyx0,ttyx1 --old-asn --route 0@127.0.0.1 --route all@192.168.90.54
Reading symbols for shared libraries +++++++++++++++........................... done
T38Modem Version 1.1.0
(H323plus-1.20.2, PWLIB-1.12.0) by Vyacheslav Frolov on Unix Darwin (9.6.0-i386)

Reading symbols for shared libraries . done
Reading symbols for shared libraries . done
Reading symbols for shared libraries . done
Reading symbols for shared libraries . done
Route O/G calls:
  0 --> 127.0.0.1
  all --> 192.168.90.54

Program received signal EXC_BAD_ACCESS, Could not access memory.
Reason: KERN_PROTECTION_FAILURE at address: 0x0000003c
0x00fd79ba in PString::operator= ()
(gdb) where
#0  0x00fd79ba in PString::operator= ()
#1  0x00025225 in PseudoModemPty::PseudoModemPty ()
#2  0x000079f9 in CreatePseudoModemPty ()
#3  0x00007ab9 in PseudoModemDrivers::CreateModem ()
#4  0x00003ed7 in PseudoModemQ::CreateModem ()
#5  0x0002bf9d in MyH323EndPoint::Initialise ()
#6  0x0002da7c in MyH323EndPoint::Create ()
#7  0x00027ccb in T38Modem::Initialise ()
#8  0x000280bd in T38Modem::Main ()
#9  0x00fbe8b2 in PProcess::_main ()
#10 0x00026f97 in main ()
(gdb)

I'm going to look into those missing library warnings, but figured you'd want to know about the crash.

[Brian Postow]

NEVER MIND. I was using the wrong version, with the same bug as before... D'OH!