Threads and MagickWand

[javiersm]

Hi!

I'm developing an app that dones an image treatment and it shows the result in a browser following the next path:

http(browser) -> Apache -> Java Module -> JNA -> my Magickwand program.

And then it returns the result to the browser.

The problem is that when I run concurrent threads it fails and lost responses. I've config ImageMagick-6.4.8-3 with '--enable-threads=posix' so I dont understand where could be the problem. The stack trace that returns Java is:

Stack: [0x044b1000,0x04502000), sp=0x044fc744, free space=301k
Native frames: (J=compiled Java code, j=interpreted, Vv=VM code, C=native code)
C 0x048a341c
C 0x048a5cb8
C [libMagickCore.so.1+0x52945] WriteImage+0x531
C [libMagickCore.so.1+0x2913c] ImageToBlob+0x1c4
C [libMagickWand.so.1+0x95f99] MagickGetImageBlob+0x55
C [libMagickWand.so.1+0x5c262] MagickWriteImageBlob+0x1e
C [libWrapWand.so+0xe6f] ImageAnnotate+0x23d
C [jna9504.tmp+0x10ec7] ffi_call_SYSV+0x17
C [jna9504.tmp+0x10b74] ffi_call+0xb4
C [jna9504.tmp+0x3671]
C [jna9504.tmp+0x3d20] Java_com_sun_jna_Function_invokePointer+0x43
j com.sun.jna.Function.invokePointer(I[Ljava/lang/Object;)Lcom/sun/jna/Pointer;+0

So it looks like it fails in 'MagickWriteImageBlob' function which i'm using in my program...

Any help will be apreciated, thanks!

Best regards.

[magick]

Theoretically ImageMagick is thread-safe. We'll try to reproduce the problem but will need a few days. If you can get your process to return a stack trace with line numbers, that would be helpful.

[javiersm]

Hi! Thanks for your support.

I don't know how to configure the log to return line numbers, sorry very much, I'll try. Meanwhile let me set out the problem with more detail, my C Program do this:

(C Code)

void* ImageAnnotate(int *iSizeOutput )
{

//this will be convert into a byte array for java.
unsigned char *psFileStreamOutput = NULL;

//Text treatment.

psFileStreamOutput = MagickGetImageBlob(wand_background, (size_t *)iSizeOutput );
return (void *)psFileStreamOutput;

}

and then I invoke this function:

void relinquishMem (void* p)
{
p = MagickRelinquishMemory(p);
}

Giving psFileStreamOutput to the function parameter, is this code ok?

I hope it will be helpful, thanks again.

best regards.