Function dfs_file_open

components/dfs/dfs_v2/src/dfs_file.c:565–824

* @brief Open a file which specified by path with specified oflags. * * This function opens or creates a file with given path and flags. It handles: * - Path normalization and resolution (including symbolic links) * - File creation when O_CREAT is specified * - Permission checking * - Directory vs regular file validation * - Symbolic link following (unless O_NOFOLLOW is set) * * @param[in

 *         -EISDIR if path is directory when opening as regular file
 */
int dfs_file_open(struct dfs_file *file, const char *path, int oflags, mode_t mode)
{
    int ret = -RT_ERROR;
    char *fullpath = RT_NULL;
    struct dfs_dentry *dentry = RT_NULL;
    int fflags = dfs_fflags(oflags);

    if (mode == 0)
    {
        mode = (S_IRUSR | S_IWUSR | S_IRGRP | S_IWGRP | S_IROTH | S_IWOTH); /* 0666 */
    }

    if (file && path)
    {
        fullpath = dfs_normalize_path(NULL, path);
        if (fullpath)
        {
            struct dfs_mnt *mnt = RT_NULL;

            DLOG(msg, "dfs_file", "mnt", DLOG_MSG, "dfs_mnt_lookup(%s)", fullpath);
            mnt = dfs_mnt_lookup(fullpath);
            if (mnt)
            {
                char *tmp = dfs_file_realpath(&mnt, fullpath, DFS_REALPATH_EXCEPT_LAST);
                if (tmp)
                {
                    rt_free(fullpath);
                    fullpath = tmp;
                }

                DLOG(msg, "dfs_file", "dentry", DLOG_MSG, "dfs_dentry_lookup(mnt, %s)", fullpath);
                dentry = dfs_dentry_lookup(mnt, fullpath, oflags);
                if (dentry && dentry->vnode->type == FT_SYMLINK)
                {
                    /* it's a symbol link but not follow */
                    if (oflags & O_NOFOLLOW)
                    {
                        /* no follow symbol link */
                        dfs_dentry_unref(dentry);
                        dentry = RT_NULL;
                    }
                    else
                    {
                        struct dfs_dentry *target_dentry = RT_NULL;
                        char *path = dfs_file_realpath(&mnt, fullpath, DFS_REALPATH_ONLY_LAST);
                        if (path)
                        {
                            target_dentry = dfs_dentry_lookup(mnt, path, oflags);
                            rt_free(path);
                        }
                        dfs_dentry_unref(dentry);
                        dentry = target_dentry;
                    }
                }

                if (dentry)
                {
                    if (oflags & O_DIRECTORY)