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#include <ipc/ipc.h>
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#include <ipc/ipc.h>
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#include <ipc/services.h>
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#include <ipc/services.h>
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#include <async.h>
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#include <async.h>
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#include <errno.h>
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#include <errno.h>
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#include <unistd.h>
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#include <unistd.h>
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#include <stdio.h>>
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#include <stdio.h>
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#include "../../vfs/vfs.h"
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#include "../../vfs/vfs.h"
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#define dprintf(...)    printf(__VA_ARGS__)
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#define dprintf(...)    printf(__VA_ARGS__)
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vfs_info_t fat_vfs_info = {
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vfs_info_t fat_vfs_info = {
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        [IPC_METHOD_TO_VFS_OP(VFS_WRITE)] = VFS_OP_NULL,
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        [IPC_METHOD_TO_VFS_OP(VFS_WRITE)] = VFS_OP_NULL,
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        [IPC_METHOD_TO_VFS_OP(VFS_SEEK)] = VFS_OP_DEFAULT
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        [IPC_METHOD_TO_VFS_OP(VFS_SEEK)] = VFS_OP_DEFAULT
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    }
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    }
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};
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};
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/*
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/**
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 * This fibril processes request from the VFS server.
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 * This connection fibril processes VFS requests from VFS.
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 *
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 * In order to support simultaneous VFS requests, our design is as follows.
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 * The connection fibril accepts VFS requests from VFS. If there is only one
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 * instance of the fibril, VFS will need to serialize all VFS requests it sends
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 * to FAT. To overcome this bottleneck, VFS can send FAT the IPC_M_CONNECT_ME_TO
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 * call. In that case, a new connection fibril will be created, which in turn
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 * will accept the call. Thus, a new phone will be opened for VFS.
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 *
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 * There are few issues with this arrangement. First, VFS can run out of
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 * available phones. In that case, VFS can close some other phones or use one
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 * phone for more serialized requests. Similarly, FAT can refuse to duplicate
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 * the connection. VFS should then just make use of already existing phones and
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 * route its requests through them. To avoid paying the fibril creation price
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 * upon each request, FAT might want to keep the connections open after the
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 * request has been completed.
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 */
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 */
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void fat_connection(ipc_callid_t iid, ipc_call_t *icall)
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static void fat_connection(ipc_callid_t iid, ipc_call_t *icall)
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{
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{
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    if (iid) {
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        /*
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         * This only happens for connections opened by
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         * IPC_M_CONNECT_ME_TO calls as opposed to callback connections
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         * created by IPC_M_CONNECT_TO_ME.
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         */
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        ipc_answer_fast(iid, EOK, 0, 0);
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    }
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    dprintf("Callback connection established.\n");
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    dprintf("VFS-FAT connection established.\n");
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    while (1) {
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    while (1) {
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        ipc_callid_t callid;
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        ipc_callid_t callid;
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        ipc_call_t call;
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        ipc_call_t call;
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        callid = async_get_call(&call);
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        callid = async_get_call(&call);
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        switch  (IPC_GET_METHOD(call)) {
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        default:
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        ipc_answer_fast(callid, ENOTSUP, 0, 0);
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            ipc_answer_fast(callid, ENOTSUP, 0, 0);
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            break;
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        }
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    }
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    }
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}
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}
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int main(int argc, char **argv)
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int main(int argc, char **argv)
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{
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{
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     * Ask VFS for callback connection.
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     * Ask VFS for callback connection.
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     */
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     */
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    ipcarg_t phonehash;
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    ipcarg_t phonehash;
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    ipc_connect_to_me(vfs_phone, 0, 0, &phonehash);
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    ipc_connect_to_me(vfs_phone, 0, 0, &phonehash);
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    /*
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     * Create a connection fibril to handle the callback connection.
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     */
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    async_new_connection(phonehash, 0, NULL, fat_connection);
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    async_new_connection(phonehash, 0, NULL, fat_connection);
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    /*
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     * Tell the async framework that other connections are to be handled by
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     * the same connection fibril as well.
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     */
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    async_set_client_connection(fat_connection);
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    /*
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    /*
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     * Pick up the answer for the request to the VFS_REQUEST call.
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     * Pick up the answer for the request to the VFS_REQUEST call.
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     */
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     */
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    async_wait_for(req, NULL);
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    async_wait_for(req, NULL);
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    dprintf("FAT filesystem registered.\n");
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    dprintf("FAT filesystem registered.\n");
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    async_create_manager();
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    /*
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    /*
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     * TODO: Interestingly, if we merely return, the only thread dies.
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     * TODO: Interestingly, if we merely return, the only thread dies.
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     *       If the only thread dies, the whole task is destroyed.
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     *   If the only thread dies, the whole task is destroyed.
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     *       Prevent the thread from exiting when there are active fibrils.
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     *   Prevent the thread from exiting when there are active fibrils.
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     */
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     */
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    fibril_schedule_next_adv(FIBRIL_FROM_DEAD);
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    fibril_schedule_next_adv(FIBRIL_FROM_DEAD);
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    /* not reached */
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    /* not reached */
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    return 0;
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    return 0;