www.digitalmars.com         C & C++   DMDScript  

digitalmars.D.learn - listener.d: Range violation.

reply Jesse Brands <jesse.brands gmail.com> writes:
Hello there,

For a small chat server thingie I'm making, I decided to use D; finding myself
with a very neat example from listener.d to get a kick start I decided to
pretty much take the example over! However, I'm stuck on a bug I can't truly
wrap my finger around. Most likely it's my own fault and I'm doing something
wrong, but considering I took the code pretty much from the example I am more
inclined to believe the example is broken.

I'll explain what happens:
 -- I start up my server (nothing wrong, it's running as it should and
listening)
 -- I telnet to it. My server accepts the connection.
 -- I use telnet to send some information. Server handles the information
properly, again, no issue.
 -- I quit telnet by using ^] and then writing quit. Breaking the connection
rather ungracefully.
 -- The server properly recognises this isn't a clean disconnect and executes
the code to remove the socket.
 -- I then get a range violation.

This is the main process and it's loop:
https://github.com/JGBrands/BlaatServer/blob/master/source/bserver.d

This is the server class, the code where it deletes the socket is at the
complete bottom in the function void destroySocket(int index);
https://github.com/JGBrands/BlaatServer/blob/master/source/server.d

The code is primarily taken over from the listener.d example like I said, the
error I get is this:
core.exception.RangeError server(61): Range violation
----------------
----------------

I'm lead to believe the function is deleting something it shouldn't, for those
interested, this is line 61 in server.d:
if (this.sset.isSet(this.reads[i])) {
May 29 2011
parent reply Dmitry Olshansky <dmitry.olsh gmail.com> writes:
On 30.05.2011 0:38, Jesse Brands wrote:

 Hello there,

 For a small chat server thingie I'm making, I decided to use D; finding myself
 with a very neat example from listener.d to get a kick start I decided to
 pretty much take the example over! However, I'm stuck on a bug I can't truly
 wrap my finger around. Most likely it's my own fault and I'm doing something
 wrong, but considering I took the code pretty much from the example I am more
 inclined to believe the example is broken.

 I'll explain what happens:
   -- I start up my server (nothing wrong, it's running as it should and
listening)
   -- I telnet to it. My server accepts the connection.
   -- I use telnet to send some information. Server handles the information
 properly, again, no issue.
   -- I quit telnet by using ^] and then writing quit. Breaking the connection
 rather ungracefully.
   -- The server properly recognises this isn't a clean disconnect and executes
 the code to remove the socket.
   -- I then get a range violation.

 This is the main process and it's loop:
 https://github.com/JGBrands/BlaatServer/blob/master/source/bserver.d

 This is the server class, the code where it deletes the socket is at the
 complete bottom in the function void destroySocket(int index);
 https://github.com/JGBrands/BlaatServer/blob/master/source/server.d

 The code is primarily taken over from the listener.d example like I said, the
 error I get is this:
 core.exception.RangeError server(61): Range violation
 ----------------
 ----------------

 I'm lead to believe the function is deleting something it shouldn't, for those
 interested, this is line 61 in server.d:
 if (this.sset.isSet(this.reads[i])) {


Just a stub in the dark, but since you are killing the last one socket, 
(that is calling destroySocket in next)
but you get your index still incremented (next returns true) so it will 
point out of array and it won't be equal to reads.length on next step.
Try adjusting that == to >= on line 60 to test this theory.

-- 
Dmitry Olshansky
May 29 2011
parent Jesse Brands <jesse.brands gmail.com> writes:
That worked, thanks a lot! I was going nuts as to why it wouldn't work!

Much loves to you!
May 29 2011