Bug 690124

Summary:	ps2ascii crashes immediately, independent of the input
Product:	Ghostscript	Reporter:	Till Kamppeter <till.kamppeter>
Component:	Text	Assignee:	Alex Cherepanov <alex>
Status:	NOTIFIED FIXED
Severity:	critical
Priority:	P4
Version:	8.63
Hardware:	PC
OS:	Linux
Customer:		Word Size:	---
Attachments:	11_gs-cjk_font_glyph_handling_fix.dpatch 12_gs-cjk_vertical_writing_metrics_fix.dpatch 13_gs-cjk_cjkps_examples.dpatch patch

Description Till Kamppeter 2008-10-15 13:08:50 UTC

See Ubuntu bug report

https://bugs.launchpad.net/bugs/281419

The reporter complains that ps2ascii (Ghostscript wrapper script to extract the
text out of a PostScript file) doe not work any more in Ghostscript 8.63. The
script crashes with the following error, independent of the input file:

------------------------------------------------------------------------------
Username@Kubuntu:~$ ps2ascii
Error: /rangecheck in --put--
Operand stack:
   --nostringval-- false setshared .inew --nostringval-- --nostringval-- 1500
--nostringval--
Execution stack:
   %interp_exit .runexec2 --nostringval-- --nostringval-- --nostringval-- 2
%stopped_push --nostringval-- --nostringval-- --nostringval-- false 1
%stopped_push 1904 2 3 %oparray_pop 1903 2 3 %oparray_pop 1887 2 3 %oparray_pop
1771 2 3 %oparray_pop --nostringval-- %errorexec_pop .runexec2 --nostringval--
--nostringval-- --nostringval-- 2 %stopped_push --nostringval-- --nostringval--
Dictionary stack:
   --dict:1163/1684(G)-- --dict:0/20(G)-- --dict:94/200(L)-- --dict:1163/1684(G)--
Current allocation mode is global
Current file position is 8319
GPL Ghostscript 8.63: Unrecoverable error, exit code 1
------------------------------------------------------------------------------

I have tried to fix/work around it by removing the "-dDELAYBIND" command line
option from the Ghostscript command line by editing the /usr/bin/ps2ascii script
appropriately. It worked for me (I tried only 2 files), but the reporter tells
that Ghostscript segfaults then. The reporter then replaced "-dDELAYBIND" by
"-dNOBIND" then and was successful with all his files then.

WDYT? Is this a viable fix?

I am very grateful for a quick answer, as tomorrow, Thursday, October 16, Ubuntu
Intrepid has release freeze.

Comment 1 Alex Cherepanov 2008-10-15 20:44:13 UTC

I cannot reproduce this problem in the current revision on Win32 or
x86 Linux.

Comment 2 Marcos H. Woehrmann 2008-10-16 08:29:11 UTC

I can't duplicate this either.  I'm using Ubuntu 8.04 on an amd64 system with Ghostscript 8.63.

Comment 3 Ralph Giles 2008-10-16 10:51:05 UTC

I cannot reproduce with 8.63 or HEAD on x86_64 Ubuntu 8.04, nor with HEAD on
Ubuntu 8.10.

I can reproduce with the gs executable shipping with Ubuntu 8.10. So the culprit
is likely one of the patches the Ubuntu applies in their package.

Comment 4 Ralph Giles 2008-10-16 13:42:05 UTC

Ok, I've confirmed using the ubuntu intrepid source package
ghostscript_8.63.dfsg.1-0ubuntu5:

./configure && make
bin/gs -Ilib -q -dNODISPLAY -dSAFER -dDELAYBIND -dWRITESYSTEMDICT -dSIMPLE -c
stop -f lib/ps2ascii.ps examples/alphabet.ps -c quit
[...works...]

rm -rf bin obj
debian/rules patch
[add -lpaper to EXTRALIBS in the makefile]
./configure && make
bin/gs -Ilib -q -dNODISPLAY -dSAFER -dDELAYBIND -dWRITESYSTEMDICT -dSIMPLE -c
stop -f lib/ps2ascii.ps examples/alphabet.ps -c quit
Error: /rangecheck in --put--

So the culprit is indeed one of the patches, and it's not our bug. If you want
help sorting this problem, it would help to at least track down which patch is
responsible.

Comment 5 Till Kamppeter 2008-10-17 00:48:55 UTC

I have found the patch which is the culprit: It is the patch
debian/patches/11_gs-cjk_font_glyph_handling_fix, which seems to add a complete
CJK handling subsystem.

Can you check this patch and perhaps find out if it is still needed and if so,
if you could fix it.

Can you also check the need of
debian/patches/12_gs-cjk_vertical_writing_metrics_fix?

Comment 6 Alex Cherepanov 2008-10-17 08:23:29 UTC

Please provide URLs to the patches or attach them to the bug report.

Comment 7 Till Kamppeter 2008-10-17 10:02:04 UTC

Created attachment 4514 [details]
11_gs-cjk_font_glyph_handling_fix.dpatch

Patch to add advanced CJK support. This patch causes this bug.

Comment 8 Till Kamppeter 2008-10-17 10:02:55 UTC

Created attachment 4515 [details]
12_gs-cjk_vertical_writing_metrics_fix.dpatch

Additional patch for vertical CJK printing

Comment 9 Till Kamppeter 2008-10-17 10:03:47 UTC

Created attachment 4516 [details]
13_gs-cjk_cjkps_examples.dpatch

Patch which adds test files for the above two patches

Comment 10 Alex Cherepanov 2008-10-18 18:18:43 UTC

Created attachment 4519 [details]
patch

Extend the size of the array for procedures scheduled for binding
in the DELAYBIND mode to 2000. Prevent an overflow when 3rd party code
(such as Ubuntu CJKV patch) defines and binds many procedures.

Comment 11 Alex Cherepanov 2008-10-18 18:25:53 UTC

The patch is committed as a rev. 9174.

DELAYBIND mode is not covered by regression testing.
Regressions cannot happen.

Comment 12 Till Kamppeter 2008-10-19 02:45:23 UTC

I have checked and it works. Text extraction works perfectly now for me with
both PostScript and PDF input file.