Buffering client data in a Server application

[charpour]

Hello,

I am implementing a server in C using the select function and I have
problems implementing a buffering system for holding client data until
the client socket is available for reading/writing (sendq and
receivq). What I am trying to do is "save" the data in the client's
recvq right after data is availiable for the socket and write buffered
data (sendq) to the socket when it's ready. The prog skeleton is like
this:

(The following is not complete C code, it's just an example)

unsigned char buffer[1024];
select(nfds, &readset, &writeset, NULL);
// select returns

for (i=0; i<MAX_CONNECTIONS; i++) {
if (FD_ISSET(i, &readset)) {
r = read(i,buffer,...);
// cli = client data structure
cli = (struct cli *) getclient(i);
//add data to the client's recvq
add_data(&cli->recvq, buffer, r);
if (has_complete_message(&cli->recvq)) {
parseline(cli);
// add results to the client's buffer (sendq) for writing them
later
}
}
if (FD_ISSET(i, &writeset)) {
// write queued data
}
....
}

Is there any code/lib for this purpose with functions like
add_data(..), read_data(...), get_message(..), get_len(..),
has_complete_message(..), probably using double linked list or
something similar

I have found some str alloc packages but they are not very good for
this purpose.

PS. If anyone have played with ircd's, I'm searching for something
similar to sbuf.c (bahamut) or linebuf.c (ratbox) with more "clear"
code;

Thanks for your time and sorry for my bad english.

 

[Kenny McCormack]

Hello,

I am implementing a server in C using the select function and I have
problems implementing a buffering system for holding client data until

Off topic. Not portable. Cant discuss it here. Blah, blah, blah.

--
Useful clc-related links:

http://en.wikipedia.org/wiki/Aspergers
http://en.wikipedia.org/wiki/Clique
http://en.wikipedia.org/wiki/C_programming_language

 

[charpour]

Off topic. Not portable. Cant discuss it here. Blah, blah, blah.

Not the answer I am seeking.

What is not portable and what is off-topic?

 

[Keith Thompson]

I am implementing a server in C using the select function and I have
problems implementing a buffering system for holding client data until
the client socket is available for reading/writing (sendq and
receivq). What I am trying to do is "save" the data in the client's
recvq right after data is availiable for the socket and write buffered
data (sendq) to the socket when it's ready. The prog skeleton is like
this:

[...]

select() is not a standard C function; it's defined by POSIX. You'll
probably get better answers by posting to comp.unix.programmer. (This
assumes you're using a Unix-like system; if not, try a newsgroup that
deals with your operating system.)

(The other rewponse you got was from one of our resident trolls.
Please ignore him; he won't help you.)

 

[charpour]

Thank you

 

[Kenny McCormack]

Not the answer I am seeking.

What is not portable and what is off-topic?

Don't ask. Any minute now, they'll tell you.

 

[CBFalconer]

I am implementing a server in C using the select function and I
have problems implementing a buffering system for holding client
data until the client socket is available for reading/writing
(sendq and receivq). What I am trying to do is "save" the data in
the client's recvq right after data is availiable for the socket
and write buffered data (sendq) to the socket when it's ready.
The prog skeleton is like this:

Ignore McCormack, he is a known troll. However your query is
largely off-topic, but appears to contain some topical C
questions. I think you need to eliminate consideration of
'servers', whatever they are, and concentrate on the intermediate
storage abilities and capabilities. What is practical here will
also depend on the peak volume of data held, the access times,
etc. I could almost recommend my hashlib package, but the
processing time involved may become excessive (for automatic
expansion of the hashtable). Or it may not.

 

[DiAvOl]

I've made a small module for buffering but I am not sure how correct
my code is (it compiles ofc, I mean in logic).
If someone can check it please and tell his opinion.

Here is the code:
http://pastebin.com/m6a3702ad

Thank you