Some questions about PC/SC Lite

Hi,

This post has 2 parts.

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I need your opinion on these concepts:

#define PCSCLITE_MAX_CHANNELS           16 /* Maximum channels */
#define PCSCLITE_MAX_APPLICATIONS       16 /* Maximum applications */
#define PCSCLITE_MAX_READERS            16 /* Maximum readers */
#define PCSCLITE_MAX_CONTEXTS           PCSCLITE_MAX_READERS

I wish your opinion on what is for you a CHANNEL, a CONTEXT, an APPLICATION, a 
READER.

CONTEXT is related for the hContext or for the hCard?

For me a READER and a CONTEXT is different. Also in the code of 
readerfactory.c, eventhandler.c et winscard_clnt.c there  is many place where I 
wish replace PCSCLITE_MAX_CONTEXTS by PCSCLITE_MAX_READERS.

I will try to explain you how I think theses concepts.

Fisrt imagine
- 3 PC/SC daemons started on 3 different hosts (it is possible to connect to 
PC/SC daemons over the network with SCardEstablishContext -- it is not yet 
implemented in PC/SC Lite):
PC/SC D1, PC/SC D2, PC/SC D3

- 4 applications :
App A, App B, App C, App D

2 readers R1 and R2 but where R2 has 2 slots that we call R2S1 and R2S2

Focus on PC/SC D1.

For me PCSC_MAX_APPLICATIONS is the maximum number of clients (with a different 
PID) that the daemon PC/SC can accept. Here for example it may be 4.
Obviously PCSC_MAX_READERS (consider a slot as a reader) is here 3 (1 readers + 
2 slots).

For me, we may be add  PCSC_MAX_CONTEXTS_CLIENT that will be the number of 
SCardEstablishContext calls that an application is allow to do. For example 
here it may be 3. 
Thus we may also introduce PCSC_MAX_CONTEXTS_SERVER that will be a maximum of 
PCSC_MAX_APPLICATIONS*PCSC_MAX_CONTEXTS_CLIENT.


PC/SC D2
        \               (1)
         ------       --------           R1
               \     /        \        /
                App A          PC/SC D1--R2S1
                     \        /  | | | \ 
                      --------   | | |   R2S2 
                        (2)      | | |
PC/SC D3                         | | |
        \                        | | |
         -------App B -----------/ | |
                                   | |
                App C -------------/ |
                                     |
                App D ---------------/

On each CONTEXT we may imagine to call many time SCardConnect creating a 
CHANNEL on it each time. On each CONTEXT it may be a maximum of 
PCSC_MAX_CHANNELS.
But we need to introduce a PCSC_MAX_CHANNELS_CLIENT_SIDE and 
PCSC_MAX_CHANNELS_READER_SIDE because for example all the applications over all 
the context may want access to the same READER (i.e. card).

Note: The App A has 2 CONTEXTs because for example it may be create 2 threads 
and each thread wishes to call SCardEstablishContext.

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What is the need of dwBlockStatus in PREADER_CONTEXT structure ?

I have the same question about the functions : 
- RFUnblockReader
- RFUnblockContext

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I wait your feedbacks on these concepts.

Damien Sauveron.


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