[Mapserver-users] mapserver crashes at a png file

[Carsten Busch]

Hello Vincent,
thank you for your answer.

Vincent Schut wrote:
> Carsten,
> 
> first about the output: that is not only the png image, but also the headers 
> as a browser would expect them. You cannot save the output as a png file. But 
> you can issue the same command in your browser by typing (in the adress field 
> of the browser):
> http://localhost/cgi-bin/mapserv?map=/bla/bla/map.map&mode=map
> Then you should see the generated png image.
Please again, where do I define the selected layers?
Does it mean, that all possible layers of the map file are selected?
> 
> About your png error: have you tried to open the png layer file with an image 
> viewer? Just to be sure that the png file is not corrupt...
It is not corrupt.
> If you can view the file, you could convert it to tiff and check if mapserver 
> can display it if you define your layer to have the tiff file as input. This 
> would track the problem down to png reading (e.g. libgd or libgdal or 
> libpng).
Ok, if I use a tiff, mapserver works. So, I could convert all raster 
Layer in the tiff format, but it will work only with grayscale raster data.
> 
> Btw, after running in gdb and the segfault, did you type 'backtrace'? This 
> gives us some more hints to where the crash appeared.
Program received signal SIGSEGV, Segmentation fault.
0x08072d72 in drawPNG ()
(gdb) backtrace
#0  0x08072d72 in drawPNG ()
#1  0x0807488e in msDrawRasterLayer ()
#2  0x080645bb in msDrawLayer ()
#3  0x08061131 in msDrawMap ()
#4  0x080556c4 in msGenerateImages ()
#5  0x0804ea7b in main ()
#6  0x402927f7 in __libc_start_main () from /lib/i686/libc.so.6
(gdb)

Thank you for your help.
> 
> Cheers,
> Vincent.
> 
> On Tuesday 24 June 2003 19:23, Carsten Busch wrote:
> 
>>Hello,
>>
>>I found the right parameter for testing:
>>(gdb) run
>>"QUERY_STRING=map=/usr/local/apache/htdocs/itasca/demo.map&layer=thueringen
>>" Starting program: /usr/local/apache/cgi-bin/mapserv
>>"QUERY_STRING=map=/usr/local/apache/htdocs/itasca/demo.map&layer=thueringen
>>"
>>
>>Program received signal SIGSEGV, Segmentation fault.
>>0x08072d72 in drawPNG ()
>>
>>lyer=thueringen, is the png layer, If I use any other (right) layer of
>>the postgis db, Iget the png image.
>>
>>Any idea?
>>
>>
>>Carsten
> 
> 


-- 




Carsten