Bugzilla Bug 74815

lftp seems to be broken when compiled againt the newest libreadline. if lftp is
compiled manually using the --with-included-readline ./configure option lftp
works without any problems. 

Reproducible: Always
Steps to Reproduce:
1. Use lftp to access a ftp site
2. use tab completion a few times with mirror/get


Actual Results:  
Segmentation fault

Expected Results:  
No Segmentation fault

Nothing special, bug can be reproduced on many diffrent gentoo instalations.

I can't reproduce this problem.
lftp-3.0.12 against readline-5.0-r1 works just fine with tab completion.

try different lftp version (say, current stable is 3.0.9) and see if that segfaults or not for you.

Also, can you provide a gdb backtrace so we can see what is causing the segfault?

works fine overhere on x86 - lftp 3.0.12 + readline 5.0-r1

I had this problem.  This is a known problem and is fixed in the next version
of lftp.  Please see
http://www.mail-archive.com/lftp%40uniyar.ac.ru/msg01819.html for the patch. 
Contact me if you need help applying the patch in the ebuild.  Was going post
it, but figured the next rev of lftp with the problem fixed is due out soon.

3.0.12-r1 added with patch described in comment 3 (Thanks Jeffery). Thomas I
hope this fixes your fault otherwise can you  provide a backtrace and reopen
this bug.

Thanks Jeffrey that did fix it. The reason i though libreadline was the curlpit
was that gdb said the crash occurred in a function loaded from libreadline.so.
Oh well, Thanks again.

I seem to be having the exact same problem with net-ftp/lftp-3.0.13, but only
on 
x86 and not on hppa. strace doesn't reveal much, though:

---------------------------------------------------------------
read(4, 0x81147e8, 65536)               = -1 EAGAIN (Resource temporarily 
unavailable)
read(4, 0x81147e8, 65536)               = -1 EAGAIN (Resource temporarily 
unavailable)                                                                    
     poll([{fd=4, events=POLLIN}], 1, 18)    = 0
gettimeofday({1122845009, 635815}, NULL) = 0                                    
read(4, 0x81147e8, 65536)               = -1 EAGAIN (Resource temporarily 
unavailable)
read(4, 0x81147e8, 65536)               = -1 EAGAIN (Resource temporarily 
unavailable)                                                                    
     --- SIGSEGV (Segmentation fault) @ 0 (0) ---
+++ killed by SIGSEGV +++
---------------------------------------------------------------

Do the unstable version lftp-3.1.4 and lftp-3.2.1 work for you? I so I'll move 
them to stable k? 
 
To debug SEGV's properly use gdb - 
http://www.gentoo.org/doc/en/bugzilla-howto.xml#doc_chap2 

(In reply to comment #7)

Gosh, that was quick! :)

> Do the unstable version lftp-3.1.4 and lftp-3.2.1 work for you? I so I'll move 
> them to stable k? 

Currently merging net-ftp/lftp-3.2.1...

> To debug SEGV's properly use gdb - 
> http://www.gentoo.org/doc/en/bugzilla-howto.xml#doc_chap2 

I'll do that.

Created an attachment (id=64829) [edit]
Backtrace from dbg

That first backtrace concerns:

jeroen@henke ~ $ lftp --version
LFTP | Version 3.2.1 | Copyright (c) 1996-2005 Alexander V. Lukyanov

LFTP is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
There is absolutely no warranty for LFTP.  See COPYING for details.

Send bug reports and questions to <lftp@uniyar.ac.ru>.

Libraries used: Readline 5.0, Expat 1.95.8, GnuTLS 1.2.3

Created an attachment (id=64831) [edit]
Backtrace from lftp 3.0.13

Created an attachment (id=64835) [edit]
Obligatory emerge info (i686, lftp 3.0.13)

Created an attachment (id=64836) [edit]
Obligatory emerge info (i586, lftp 3.2.1)

The tabbing segfault occurs as well with these versions of lftp:

henke ~ # qlop -l lftp | grep -o '>>>.*' | sort | uniq
...
>>> net-ftp/lftp-3.3.0
>>> net-ftp/lftp-3.3.3
>>> net-ftp/lftp-3.3.4

For instance:

jeroen@epia ~ $ lftpkernel
cd ok, cwd=/pub/linux/kernel
lftp ftp.kernel.org:/pub/linux/kernel> cd /
lftp ftp.kernel.org:/> cd pub/linux/kernel/peSegmentation fault                 
jeroen@epia ~ $

So what exactly has been resolved/fixed?

Same with 3.3.4-r1.

Oops.

Interesting to note that in debug mode, lftp crashes a lot less (race 
condition?). Assuming remote-completion is the problem, I tried to do without 
(using 3.3.4-r1):

----------
jeroen@epia ~ $ lftp -v
LFTP | Version 3.3.4 | Copyright (c) 1996-2005 Alexander V. Lukyanov

LFTP is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
There is absolutely no warranty for LFTP.  See COPYING for details.

Send bug reports and questions to <lftp@uniyar.ac.ru>.

Libraries used: Readline 5.0, Expat 1.95.8, GnuTLS 1.2.3
jeroen@epia ~ $ lftp ftp://ftp.kernel.org/
cd ok, cwd=/
lftp ftp.kernel.org:/> set cmd:remote-completion false
lftp ftp.kernel.org:/> cd /<<TAB>>lftp: complete.cc:832: char** lftp_completion
(const char*, int, int): Assertion `generator' failed.
Aborted
jeroen@epia ~ $
----------

Seems like I can't even turn it off to prevent segfaults.

*** Bug 95958 has been marked as a duplicate of this bug. ***

I finally bit the bullet and went --with-included-readline

Sorry it took so long. I'm stuborn in a bad way sometimes.

details - this is included in 3.4.0.

Thanks for everyones help.

3.4.0-r1 reverts to using system readline-5.1 as it doesn't break it- thanks 
Peter Kerwien

(In reply to comment #21)
> 3.4.0-r1 reverts to using system readline-5.1 as it doesn't break it- thanks 
> Peter Kerwien

Breaks for me... Same [tab][tab]SEGFAULT problem as before, while 3.4.0 was the
first version in a long time that didn't exhibit the bug. Shall we just stick
with the --with-included-readline for now? :)

> Breaks for me... Same [tab][tab]SEGFAULT problem as before, while 3.4.0 was the
> first version in a long time that didn't exhibit the bug. Shall we just stick
> with the --with-included-readline for now? :)
> 

Have you also updated to readline-5.1-r2? I have a bulletproof TAB-sequence
that crashed lftp everytime and I also so it disappeared with
--with-included-readline but also when upgrading readline from 5.0 to 5.1-r2.

If lftp needs sys-libs/readline-5.1-r2 to get this bug fixed, then
>=sys-libs/readline-5.1 should probably be in RDEPEND, which is currently only
the case for ppc-macos.

opps should of  been RDEPEND=!ppc-macos ( >=readline-5.1 )

sorry.

Upgrade readline to >readline-5.1 and you should be good.