Crocos Code

/* fd.c
 * 
 * Copyright (C) 2009 Guillaume Duranceau
 * This file is part of CROCOS.
 *
 * This file is distributed under the terms of the GNU General Public License.
 * This license is available in the COPYING file, in the main repository.
 */

#include "config/config.h"
#include "fs/fd.h"
#include "fs/inode.h"
#include "fs/vfs.h"
#include "intr/errno.h"
#include "klibc/list.h"
#include "klibc/stdbool.h"
#include "klibc/stddef.h"
#include "process/pcb.h"

void fd_init_process (struct pcb *process) {
    int fd; for (fd = 0; fd < CONFIG_FS_MAX_FD; fd++)
        process->fd_tbl[fd].used = false;
}

void fd_kill_process (struct pcb *process) {
    /* close opened file descriptors */
    int fd; for (fd = 0; fd < CONFIG_FS_MAX_FD; fd++)
        if (process->fd_tbl[fd].used) fs_close (process, fd);
}

void fd_copy_fd_tbl (struct pcb *process_src, struct pcb *process_dest) {
    int fd; for (fd = 0; fd < CONFIG_FS_MAX_FD; fd++) {
        struct fd *src_fd = process_src->fd_tbl + fd;
        struct fd *dest_fd = process_dest->fd_tbl + fd;
        dest_fd->used = src_fd->used;
        dest_fd->inode = src_fd->inode;
        dest_fd->flags = src_fd->flags;
        dest_fd->offset = src_fd->offset;
    }
}

int fd_allocate (struct pcb *process, struct inode *inode, int flags) {
    struct fd *freefd;
    int fd; for (fd = 0; fd < CONFIG_FS_MAX_FD; fd++)
        if (!process->fd_tbl[fd].used) break;
    if (fd == CONFIG_FS_MAX_FD) return -EMFILE;
    freefd = process->fd_tbl + fd;
    freefd->used = true;
    freefd->inode = inode;
    freefd->flags = flags;
    freefd->offset = 0;
    return fd;
}

void fd_free (struct pcb *process, int fd) {
    process->fd_tbl[fd].used = false;
}

struct fd *fd_get (struct pcb *process, int fd) {
    if ((fd < 0) || (fd >= CONFIG_FS_MAX_FD) || (!(process->fd_tbl[fd].used)))
        return NULL;
    return process->fd_tbl + fd;
}