Archipelago » qemu

common-obj-y += block-migration.o iohandler.o

/*

 * QEMU System Emulator - managing I/O handler

 *

 * Copyright (c) 2003-2008 Fabrice Bellard

 *

 * Permission is hereby granted, free of charge, to any person obtaining a copy

 * of this software and associated documentation files (the "Software"), to deal

 * in the Software without restriction, including without limitation the rights

 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

 * copies of the Software, and to permit persons to whom the Software is

 * furnished to do so, subject to the following conditions:

 *

 * The above copyright notice and this permission notice shall be included in

 * all copies or substantial portions of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL

 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

 * THE SOFTWARE.

 */

#include "config-host.h"

#include "qemu-common.h"

#include "qemu-char.h"

#include "qemu-queue.h"

typedef struct IOHandlerRecord {

    int fd;

    IOCanReadHandler *fd_read_poll;

    IOHandler *fd_read;

    IOHandler *fd_write;

    int deleted;

    void *opaque;

    QLIST_ENTRY(IOHandlerRecord) next;

} IOHandlerRecord;

static QLIST_HEAD(, IOHandlerRecord) io_handlers =

    QLIST_HEAD_INITIALIZER(io_handlers);

/* XXX: fd_read_poll should be suppressed, but an API change is

   necessary in the character devices to suppress fd_can_read(). */

int qemu_set_fd_handler2(int fd,

                         IOCanReadHandler *fd_read_poll,

                         IOHandler *fd_read,

                         IOHandler *fd_write,

                         void *opaque)

{

    IOHandlerRecord *ioh;

    if (!fd_read && !fd_write) {

        QLIST_FOREACH(ioh, &io_handlers, next) {

            if (ioh->fd == fd) {

                ioh->deleted = 1;

                break;

            }

        }

    } else {

        QLIST_FOREACH(ioh, &io_handlers, next) {

            if (ioh->fd == fd)

                goto found;

        }

        ioh = qemu_mallocz(sizeof(IOHandlerRecord));

        QLIST_INSERT_HEAD(&io_handlers, ioh, next);

    found:

        ioh->fd = fd;

        ioh->fd_read_poll = fd_read_poll;

        ioh->fd_read = fd_read;

        ioh->fd_write = fd_write;

        ioh->opaque = opaque;

        ioh->deleted = 0;

    }

    return 0;

}

int qemu_set_fd_handler(int fd,

                        IOHandler *fd_read,

                        IOHandler *fd_write,

                        void *opaque)

{

    return qemu_set_fd_handler2(fd, NULL, fd_read, fd_write, opaque);

}

void qemu_iohandler_fill(int *pnfds, fd_set *readfds, fd_set *writefds, fd_set *xfds)

{

    IOHandlerRecord *ioh;

    QLIST_FOREACH(ioh, &io_handlers, next) {

        if (ioh->deleted)

            continue;

        if (ioh->fd_read &&

            (!ioh->fd_read_poll ||

             ioh->fd_read_poll(ioh->opaque) != 0)) {

            FD_SET(ioh->fd, readfds);

            if (ioh->fd > *pnfds)

                *pnfds = ioh->fd;

        }

        if (ioh->fd_write) {

            FD_SET(ioh->fd, writefds);

            if (ioh->fd > *pnfds)

                *pnfds = ioh->fd;

        }

    }

}

void qemu_iohandler_poll(fd_set *readfds, fd_set *writefds, fd_set *xfds, int ret)

{

    if (ret > 0) {

        IOHandlerRecord *pioh, *ioh;

        QLIST_FOREACH_SAFE(ioh, &io_handlers, next, pioh) {

            if (!ioh->deleted && ioh->fd_read && FD_ISSET(ioh->fd, readfds)) {

                ioh->fd_read(ioh->opaque);

            }

            if (!ioh->deleted && ioh->fd_write && FD_ISSET(ioh->fd, writefds)) {

                ioh->fd_write(ioh->opaque);

            }

            /* Do this last in case read/write handlers marked it for deletion */

            if (ioh->deleted) {

                QLIST_REMOVE(ioh, next);

                qemu_free(ioh);

            }

        }

    }

}

void qemu_iohandler_fill(int *pnfds, fd_set *readfds, fd_set *writefds, fd_set *xfds);

void qemu_iohandler_poll(fd_set *readfds, fd_set *writefds, fd_set *xfds, int rc);

    tv.tv_sec = timeout / 1000;

    tv.tv_usec = (timeout % 1000) * 1000;

    qemu_iohandler_fill(&nfds, &rfds, &wfds, &xfds);

    qemu_iohandler_poll(&rfds, &wfds, &xfds, ret);