Subversion Repositories c0or1k

/*

 * l4/posix glue for read() / sys_readdir()

 *

 * Copyright (C) 2007 Bahadir Balban

 */

#include <errno.h>

#include <stdio.h>

#include <string.h>

#include <sys/types.h>

#include <unistd.h>

#include <l4lib/ipcdefs.h>

#include <l4lib/os/posix/readdir.h>

#include <l4/macros.h>

#include INC_GLUE(memory.h)

#include INC_GLUE(message.h)

#include <libposix.h>

/*

 * TODO:

 *

 * Do this as follows:

 *

 * A short ipc l4_send() to indicate request

 * An extended l4_receive_extended() to get back extended buffer.

 *

 * Or do it just like read()

 */

static inline int l4_readdir(int fd, void *buf, size_t count)

{

        int cnt, err;

        write_mr(L4SYS_ARG0, fd);

        write_mr(L4SYS_ARG1, count);

        /* Call pager with readdir() request. Check ipc error. */

        if ((err = l4_send(pagerid, L4_IPC_TAG_READDIR)) < 0) {

                print_err("%s: L4 IPC Error: %d.\n", __FUNCTION__, err);

                return err;

        }

        /* Call pager with readdir() request. Check ipc error. */

        if ((err = l4_receive_extended(pagerid,

                                       L4_IPC_EXTENDED_MAX_SIZE,

                                       buf)) < 0) {

                print_err("%s: L4 Extended IPC error: %d.\n", __FUNCTION__, err);

                return err;

        }

        /* Check if syscall itself was successful */

        if ((cnt = l4_get_retval()) < 0) {

                print_err("%s: READDIR Error: %d.\n", __FUNCTION__, (int)cnt);

                return cnt;

        }

        return cnt;

}

#if 0

static inline int l4_readdir(int fd, void *buf, size_t count)

{

        int cnt;

        write_mr(L4SYS_ARG0, fd);

        write_mr(L4SYS_ARG1, (unsigned long)buf);

        write_mr(L4SYS_ARG2, count);

        /* Call pager with readdir() request. Check ipc error. */

        if ((cnt = l4_sendrecv(pagerid, pagerid, L4_IPC_TAG_READDIR)) < 0) {

                print_err("%s: L4 IPC Error: %d.\n", __FUNCTION__, cnt);

                return cnt;

        }

        /* Check if syscall itself was successful */

        if ((cnt = l4_get_retval()) < 0) {

                print_err("%s: READDIR Error: %d.\n", __FUNCTION__, (int)cnt);

                return cnt;

        }

        return cnt;

}

#endif

static inline int l4_read(int fd, void *buf, size_t count)

{

        int cnt;

        write_mr(L4SYS_ARG0, fd);

        write_mr(L4SYS_ARG1, (unsigned long)buf);

        write_mr(L4SYS_ARG2, count);

        /* Call pager with read() request. Check ipc error. */

        if ((cnt = l4_sendrecv(pagerid, pagerid, L4_IPC_TAG_READ)) < 0) {

                print_err("%s: L4 IPC Error: %d.\n", __FUNCTION__, cnt);

                return cnt;

        }

        /* Check if syscall itself was successful */

        if ((cnt = l4_get_retval()) < 0) {

                print_err("%s: READ Error: %d.\n", __FUNCTION__, (int)cnt);

                return cnt;

        }

        return cnt;

}

ssize_t read(int fd, void *buf, size_t count)

{

        int ret;

        if (!count)

                return 0;

        ret = l4_read(fd, buf, count);

        /* If error, return positive error code */

        if (ret < 0) {

                errno = -ret;

                return -1;

        }

        /* else return value */

        return ret;

}

ssize_t os_readdir(int fd, void *buf, size_t count)

{

        int ret;

        if (!count)

                return 0;

        ret = l4_readdir(fd, buf, count);

        /* If error, return positive error code */

        if (ret < 0) {

                errno = -ret;

                return -1;

        }

        /* else return value */

        return ret;

}