Function fd_is_open

components/dfs/dfs_v1/src/dfs.c:491–541

* @ingroup group_fs_file_descriptor * * This function will return whether this file has been opend. * * @param pathname the file path name. * * @return 0 on file has been open successfully, -1 on open failed. */

 * @return 0 on file has been open successfully, -1 on open failed.
 */
int fd_is_open(const char *pathname)
{
    char *fullpath;
    unsigned int index;
    struct dfs_filesystem *fs;
    struct dfs_file *fd;
    struct dfs_fdtable *fdt;

    fdt = dfs_fdtable_get();
    fullpath = dfs_normalize_path(NULL, pathname);
    if (fullpath != NULL)
    {
        char *mountpath;
        fs = dfs_filesystem_lookup(fullpath);
        if (fs == NULL)
        {
            /* can't find mounted file system */
            rt_free(fullpath);

            return -1;
        }

        /* get file path name under mounted file system */
        if (fs->path[0] == '/' && fs->path[1] == '\0')
            mountpath = fullpath;
        else
            mountpath = fullpath + strlen(fs->path);

        dfs_lock();

        for (index = 0; index < fdt->maxfd; index++)
        {
            fd = fdt->fds[index];
            if (fd == NULL || fd->vnode->fops == NULL || fd->vnode->path == NULL) continue;

            if (fd->vnode->fs == fs && strcmp(fd->vnode->path, mountpath) == 0)
            {
                /* found file in file descriptor table */
                rt_free(fullpath);
                dfs_unlock();

                return 0;
            }
        }
        dfs_unlock();

        rt_free(fullpath);
    }

    return -1;
}

/**
 * @brief Duplicates a file descriptor to a specified file descriptor.