vfs_utime.c 文件参考

浏览源代码.

函数
int	utime (const char *path, const struct utimbuf *ptimes)

函数说明

utime()

int utime	(	const char *	path,
		const struct utimbuf *	ptimes
	)

在文件 vfs_utime.c 第 50 行定义.

{
    int ret;
    char *fullpath = NULL;
    struct Vnode *vnode = NULL;
    time_t cur_sec;
    struct IATTR attr = {0};
 
    /* Sanity checks *///健全性检查
 
 
    if (path == NULL) {
        ret = -EINVAL;
        goto errout;
    }
 
    if (!path[0]) {
        ret = -ENOENT;
        goto errout;
    }
    //找到绝对路径
    ret = vfs_normalize_path((const char *)NULL, path, &fullpath);
    if (ret < 0) {
        goto errout;
    }
 
    /* Get the vnode for this file */
    VnodeHold();
    ret = VnodeLookup(fullpath, &vnode, 0);//找到vnode节点
    if (ret != LOS_OK) {
        VnodeDrop();
        goto errout_with_path;
    }
 
    if ((vnode->originMount) && (vnode->originMount->mountFlags & MS_RDONLY)) {
        VnodeDrop();
        ret = -EROFS;
        goto errout_with_path;
    }
 
    if (vnode->vop && vnode->vop->Chattr) {//验证接口都已经实现
        if (ptimes == NULL) {//参数没有给时间
            /* get current seconds */
            cur_sec = time(NULL);//获取当前秒
            attr.attr_chg_atime = cur_sec;//更新访问时间
            attr.attr_chg_mtime = cur_sec;//更新修改时间
        } else {//采用参数时间
            attr.attr_chg_atime = ptimes->actime;//更新访问时间
            attr.attr_chg_mtime = ptimes->modtime;
        }
        attr.attr_chg_valid = CHG_ATIME | CHG_MTIME;//更新了两个时间
        ret = vnode->vop->Chattr(vnode, &attr);//调用接口更新数据
        if (ret != OK) {
            VnodeDrop();
            goto errout_with_path;
        }
    } else {
        ret = -ENOSYS;
        VnodeDrop();
        goto errout_with_path;
    }
    VnodeDrop();
 
    /* Successfully stat'ed the file */
    free(fullpath);
 
    return OK;
 
    /* Failure conditions always set the errno appropriately */
 
errout_with_path:
    free(fullpath);
errout:
 
    if (ret != 0) {
        set_errno(-ret);
    }
    return VFS_ERROR;
}

函数调用图:

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