On Tue, 03 Sep 2013 19:18:42 +0200, Sönke Ludwig wrote:

Am 03.09.2013 18:19, schrieb Craig Dillabaugh:

Hello,
I have a small server set up to serve image tiles as raw binary files. The 'app' consists of a HTML canvas page which uses an XMLHttpRequest() to request tiles from the server, which serves the tiles as raw data, which is then displayed on the canvas.

The whole app (minus the canvas2.html file) can be found here:

http://dpaste.com/hold/1364821/

Initially, it was working and I was able to serve and display tiles on my Canvas. Now my application crashes whenever I attempt to access a tile. The output from DUB is as follows:

(...)

I have no idea what the cause of this error is. Any advice on how to track this down would be appreciated.

Craig

Try doing "dub build" followed by "gdb ./name-of-app", enter "r" to run
and then, after it has crashed, "bt" to get a stack trace. Hopefully
that gives enough information to find the cause.

I get the following stack trace. It seems like the problem is with passing the request data to the getTile() function.
I am not really sure how to interpret the stack trace, but it seems odd that the 'this' pointer (at #1) points to the
same address passed to req in #0, which isn't what I would expect, as I assume 'this' is the function pointer to
app.getTile().

Stack trace:
0x0000000000565e13 in app.getTile() (res=0x18, req=0x565e08 <app.getTile()>) at source/app.d:17
17 void getTile(HTTPServerRequest req, HTTPServerResponse res)
Missing separate debuginfos, use: zypper install glibc-debuginfo-2.15-22.17.1.x8664 libevent-20-5-debuginfo-2.0.10-9.1.2.x8664 libopenssl100-debuginfo-1.0.1e-2.8.1.x8664 zlib-debuginfo-1.2.7-2.1.2.x8664
(gdb) bt
#0 0x0000000000565e13 in app.getTile() (res=0x18, req=0x565e08 ) at source/app.d:17
#1 0x0000000000589500 in std.functional._T13DelegateFakerTPFC4vibe4http6server17HTTPServerRequestC4vibe4http6server18HTTPServerResponseZvZ.DelegateFaker.doIt() ( 

this=0x565e08 <app.getTile()>, a1=0x999010, a0=0x9b93c0) at /usr/include/dmd/phobos/std/functional.d:705

#2 0x00000000005e54b9 in vibe.http.router.URLRouter.handleRequest() (this=0x7ffff7ecac00, res=0x999010, req=0x9b93c0) at ../../.dub/packages/vibe-d-master/source/vibe/http/router.d:159
#3 0x00000000005e2a7a in vibe.http.server.handleRequest() (keepalive=, settings=0x7ffff7ff8d98, listeninfo=..., peeraddress=..., httpstream=0x9985b8) 

at ../../.dub/packages/vibe-d-master/source/vibe/http/server.d:1267

#4 0x00000000005e1373 in vibe.http.server.handleHTTPConnection() (listeninfo=..., connection=0x9985b8) at ../../.dub/packages/vibe-d-master/source/vibe/http/server.d:1060
#5 0x00000000005dda0c in vibe.http.server.listenHTTPPlain() (this=0x7ffff7ec84c0, conn=0x9985b8) at ../../.dub/packages/vibe-d-master/source/vibe/http/server.d:122
#6 0x0000000000619b36 in vibe.core.drivers.libevent2tcp.onConnect() (this=0x997e90) at ../../.dub/packages/vibe-d-master/source/vibe/core/drivers/libevent2tcp.d:444
#7 0x000000000061e46a in vibe.core.core.CoreTask.run() (this=0x7ffff7ec5d00) at ../../.dub/packages/vibe-d-master/source/vibe/core/core.d:588
#8 0x000000000068f786 in core.thread.Fiber.run() ()
#9 0x000000000068f691 in fiberentryPoint ()
#10 0x0000000000000000 in ?? ()

Craig