阅读说明：本技术 一种覆盖写和追加写正常报错的方法、系统、设备及介质 (Method, system, equipment and medium for normal error reporting of overwriting and additional writing ) 是由 刘耀丹 于 2021-06-25 设计创作，主要内容包括：本发明公开了一种覆盖写和追加写正常报错的方法、系统、设备和存储介质,方法包括：响应于对文件进行追加写或覆盖写,向服务端发送获取权限请求；响应于接收到所述获取权限请求,根据所述获取权限请求获取所述文件的一次写入多次读取属性；根据所述一次写入多次读取属性判断所述文件是否在保护期内；以及响应于所述文件在保护期内,向客户端返回只读权限以使得所述客户端正常报错。本发明根据一次写入多次读取属性,在保护期内向客户端返回只读权限,提高后端服务器处理客户端请求的效率,进一步加强网络数据处理能力,提高网络的灵活性和可用性。(The invention discloses a method, a system, equipment and a storage medium for normal error reporting of overwriting and additional writing, wherein the method comprises the following steps: responding to the additional writing or the overwriting of the file, and sending an authority acquisition request to a server; responding to the received permission obtaining request, and obtaining the write-once read-many attribute of the file according to the permission obtaining request; judging whether the file is in a protection period or not according to the write-once read-many attribute; and responding to the file in the protection period, returning a read-only permission to the client so that the client normally reports errors. According to the write-once read-many attribute, the read-only permission is returned to the client in the protection period, the efficiency of processing the client request by the back-end server is improved, the network data processing capacity is further enhanced, and the flexibility and the usability of the network are improved.)

1. A method for normal error reporting of overwriting and additional writing is characterized by comprising the following steps:

responding to the additional writing or the overwriting of the file, and sending an authority acquisition request to a server;

responding to the received permission obtaining request, and obtaining the write-once read-many attribute of the file according to the permission obtaining request;

judging whether the file is in a protection period or not according to the write-once read-many attribute; and

and responding to the file in the protection period, and returning a read-only permission to the client so that the client normally reports errors.

2. The method according to claim 1, wherein the obtaining the write-once-read-many attribute of the file according to the obtaining permission request comprises:

and calling an attribute obtaining function in the static link library to transfer corresponding parameters so as to obtain the write-once read-many attribute character string of the file.

3. The method of claim 2, wherein determining whether the file is in a protection period according to the write-once read-many attribute comprises:

and analyzing the write-once read-many attribute character string to acquire preset type data.

4. The method of claim 3, wherein determining whether the file is in a protection period according to the write-once read-many attribute comprises:

and carrying out format conversion on the preset type of data to obtain the grace period time, the guard period time and the current time.

5. The method of claim 4, wherein determining whether the file is in a protection period according to the write-once read-many attribute comprises:

judging whether the current time is greater than the grace period time or not; and

and responding to the fact that the current time is larger than the grace period time, and judging whether the current time is smaller than the protection period time.

6. The method according to claim 1, wherein the obtaining the write-once-read-many attribute of the file according to the obtaining permission request comprises:

and judging whether the write-once read-many attribute of the file is valid or not.

7. The method of claim 1, wherein returning read-only permission to a client such that the client normally reports an error comprises:

and giving read-only permission to the permission parameter of the acquisition permission request structure body.

8. A system for normal error reporting for overwriting and appending, comprising:

the sending module is configured to respond to the additional writing or the overwriting of the file and send a permission obtaining request to the server;

the acquisition module is configured to respond to the received acquisition permission request and acquire the write-once read-many attribute of the file according to the acquisition permission request;

the judging module is configured to judge whether the file is in a protection period according to the write-once read-many attribute; and

and the execution module is configured to respond to the file in the protection period and return a read-only permission to the client so that the client normally reports errors.

9. A computer device, comprising:

at least one processor; and

a memory storing computer instructions executable on the processor, the instructions when executed by the processor implementing the steps of the method of any one of claims 1 to 7.

10. A computer-readable storage medium, in which a computer program is stored which, when being executed by a processor, carries out the steps of the method according to any one of claims 1 to 7.

Technical Field

The present invention relates to the field of data processing, and more particularly, to a method, a system, a computer device, and a readable medium for normal error reporting in overwriting and appending.

Background

A Network File System (NFS) is used for sharing a File directory between Linux systems, is one of File systems supported by FreeBSD (UNIX operating System), and allows computers in a Network to share resources through a TCP (Transmission Control Protocol)/IP (Internet Protocol) Network. In the application of NFS, a client application of a local NFS can transparently read and write files located on a remote NFS server, just like accessing local files.

The file system operation word refers to a series of methods for operating files, and the idea of the Linux system is that all files are essential, and the files cannot only store information and must allow the information to be operated. The NFS operation words mainly include 30 operation words such as open (open), read (write), create (create), delete (remove), set attribute (setatter), get attribute (getatter), hard link (link), commit (commit), read directory content (readdir), rename (rename), and update (renew).

After a WORM (Write one Read Man) attribute is set for a certain file, in a WORM protection period, a user is not allowed to Write data into the file, the original NFS adopts echo to perform additional writing and overlay writing on the file at a client side, no error is reported, the file is checked through a cat command, and the content of the file is not changed. If the client writes data into the file without viewing the content of the file, the data is written successfully, and the data is actually not written.

Disclosure of Invention

In view of this, embodiments of the present invention provide a method, a system, a computer device, and a computer readable storage medium for overwriting and appending normal error reporting, where according to a write-once read-many attribute, a read-only permission is returned to a client within a protection period, so as to improve efficiency of a backend server in processing a client request, further enhance network data processing capability, and improve flexibility and availability of a network.

Based on the above object, an aspect of the embodiments of the present invention provides a method for normal error reporting of overwrite and append write, including the following steps: responding to the additional writing or the overwriting of the file, and sending an authority acquisition request to a server; responding to the received permission obtaining request, and obtaining the write-once read-many attribute of the file according to the permission obtaining request; judging whether the file is in a protection period or not according to the write-once read-many attribute; and responding to the file in the protection period, returning a read-only permission to the client so that the client normally reports errors.

In some embodiments, the obtaining the write-once read-many attribute of the file according to the obtaining permission request includes: and calling an attribute obtaining function in the static link library to transfer corresponding parameters so as to obtain the write-once read-many attribute character string of the file.

In some embodiments, said determining whether said file is within a protection period according to said write-once read-many attribute comprises: and analyzing the write-once read-many attribute character string to acquire preset type data.

In some embodiments, said determining whether said file is within a protection period according to said write-once read-many attribute comprises: and carrying out format conversion on the preset type of data to obtain the grace period time, the guard period time and the current time.

In some embodiments, said determining whether said file is within a protection period according to said write-once read-many attribute comprises: judging whether the current time is greater than the grace period time or not; and in response to the current time being greater than the grace period time, determining whether the current time is less than the guard period time.

In some embodiments, the obtaining the write-once read-many attribute of the file according to the obtaining permission request includes: and judging whether the write-once read-many attribute of the file is valid or not.

In some embodiments, the returning read-only permission to the client so that the client normally reports an error comprises: and giving read-only permission to the permission parameter of the acquisition permission request structure body.

In another aspect of the embodiments of the present invention, a system for normal error reporting of overwriting and additional writing is provided, which includes: the sending module is configured to respond to the additional writing or the overwriting of the file and send a permission obtaining request to the server; the acquisition module is configured to respond to the received acquisition permission request and acquire the write-once read-many attribute of the file according to the acquisition permission request; the judging module is configured to judge whether the file is in a protection period according to the write-once read-many attribute; and the execution module is configured to respond to the file in the protection period and return a read-only permission to the client so that the client normally reports errors.

In another aspect of the embodiments of the present invention, there is also provided a computer device, including: at least one processor; and a memory storing computer instructions executable on the processor, the instructions when executed by the processor implementing the steps of the method as above.

In a further aspect of the embodiments of the present invention, a computer-readable storage medium is also provided, in which a computer program for implementing the above method steps is stored when the computer program is executed by a processor.

The invention has the following beneficial technical effects: and according to the write-once and read-many attributes, a read-only right is returned to the client in the protection period, so that the efficiency of processing the client request by the back-end server is improved, the network data processing capacity is further enhanced, and the flexibility and the usability of the network are improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other embodiments can be obtained by using the drawings without creative efforts.

FIG. 1 is a diagram illustrating an embodiment of a method for overwriting and appending normal error messages according to the present invention;

FIG. 2 is a schematic diagram of a hardware structure of an embodiment of a computer device for overwriting and appending normal error reporting provided by the present invention;

FIG. 3 is a diagram of a computer storage medium for overwriting and appending normal error reporting according to an embodiment of the present invention.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the following embodiments of the present invention are described in further detail with reference to the accompanying drawings.

It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are used for distinguishing two entities with the same name but different names or different parameters, and it should be noted that "first" and "second" are merely for convenience of description and should not be construed as limitations of the embodiments of the present invention, and they are not described in any more detail in the following embodiments.

The client performs overwrite (command is, for example, echo "11" > file) and additional write (command is, for example, echo "11" > > file) on the file in the WORM protection period, and the following results are obtained:

[[email protected] acl_0524]#cat file

22

[[email protected] acl_0524]#echo“11”>file

[[email protected] acl_0524]#cat file

22

[[email protected] acl_0524]#echo“11”>>file

[[email protected] acl_0524]#cat file

22

from the above results, it was found that the contents of the file were not changed, and were always "22" and no error was reported, regardless of whether overwriting or additional writing was performed.

The client overwrites the file in the WORM protection period, and the server captures the packet, so that the client can be seen to send four operation word requests including GETATTR, ACCESS (acquisition permission), SETATTR and WRITE to the server, wherein the ACCESS returned by the server to the client is RD, MD, XT and XE; the WRITE error code returned by the server to the client is NFS3ERR _ PERM, that is, the client does not report an error in the protection period of the file.

The client performs additional writing on the file in the WORM protection period, performs packet capture on the server, and can see that the client sends three operation word requests of GETATTR, ACCESS and WRITE to the server, wherein ACCESS authority returned to the client by the server is RD, MD and XT; the WRITE error code returned by the server to the client is NFS3ERR _ PERM, that is, the client does not report an error in the protection period of the file.

And returning different error codes to the client through the write operation word, and finding that the client does not report errors through testing.

The embodiment of the invention aims to solve the problem that the additional writing and the overlay writing in the WORM protection period cannot normally report errors. When the client performs additional writing or covering writing on an existing file, the client sends an ACCESS request to the server, in the embodiment of the invention, the server acquires the WORM attribute of the file by using the ACCESS request, judges whether the file is in a WORM protection period, if so, returns a read-only permission to the ACCESS request, and if the client receives the read-only permission returned by the server, the client reports an error; no write request is sent to the server, and thus no data is written into the file.

In view of the above-mentioned objects, a first aspect of the embodiments of the present invention proposes an embodiment of a method for overwriting and appending normal error reporting. FIG. 1 is a diagram illustrating an embodiment of a method for overwriting and appending normal error reporting according to the present invention. As shown in fig. 1, the embodiment of the present invention includes the following steps:

s1, responding to the additional writing or the overwriting of the file, and sending an authority acquisition request to the server;

s2, responding to the received permission acquisition request, and acquiring write-once read-many attributes of the file according to the permission acquisition request;

s3, judging whether the file is in a protection period according to the write-once read-many attribute; and

and S4, responding to the file in the protection period, returning a read-only right to the client so that the client normally reports errors.

When a file is actually written, there are two ways to write the file: overwrite and append writes. The 'overwriting' means that the content of an original file is removed, new content is written in, and the file is written in by adopting an overwriting mode by default; "additional writing" means writing content at the end of an existing file, retaining the original file content, and generally adopting additional writing when writing a log file. WORM (Write one Read Man) technology, the functional characteristic can realize that a user sets a grace period and a protection period for a directory, and a file under the directory enters the protection period to prevent data in the file from being modified and deleted. The WORM function is intended to protect archived data.

WORM grace period: the WORM property is initialized when the file is created, and if the file exceeds the user-set grace period since the last time the file is modified, the file enters a WORM protected state, namely, is set to a read-only state. WORM protection period: after the file enters the protection period, the user can only read the content of the file, and does not have any data and metadata modifying operation such as modification, deletion, movement, renaming and the like. After the protection period expires, the WORM protection state is invalid, and at this time, the user is allowed to read, modify, delete and the like the file.

And responding to the additional writing or the overwriting of the file, and sending an acquisition permission request to the server. As can be seen from the above example, no matter the write is the append write or the overwrite write, the server returns an error code to the client through the write operation word, and the client does not report an error. The ACCESS operation request is sent by the additional write and coverage write equal-release server side through packet capture at the server side, and the read-only permission can be returned to the client side through the ACCESS so that the client side can report errors. And when the existing file is subjected to additional writing or overwriting, transmitting an acquisition Authority (ACCESS) request to the server.

And responding to the received permission obtaining request, and obtaining the write-once read-many attribute of the file according to the permission obtaining request.

In some embodiments, the obtaining the write-once read-many attribute of the file according to the obtaining permission request includes: and calling an attribute obtaining function in the static link library to transfer corresponding parameters so as to obtain the write-once read-many attribute character string of the file. When the server receives an ACCESS request of the client, the server calls a lib (static link library) interface getxattr (attribute acquisition) function, a transfer parameter' icfs.

In some embodiments, the obtaining the write-once read-many attribute of the file according to the obtaining permission request includes: and judging whether the write-once read-many attribute of the file is valid or not. In some cases, there may be network fluctuation or other abnormal conditions, and in order to improve the accuracy of determining whether the file is in the protection period, it may be determined whether the write-once read-many attribute of the file is valid. Whether the write-once read-many attribute of the file is valid or not can be judged by setting an identifier, for example, a specific identifier is added when the file is input, whether the identifier is correct or not is detected when the write-once read-many attribute of the file is judged to be valid or not, and if the identifier is correct, the write-once read-many attribute of the file is indicated to be valid. Otherwise, there may be a risk of tampering.

And judging whether the file is in a protection period or not according to the write-once read-many attribute.

In some embodiments, said determining whether said file is within a protection period according to said write-once read-many attribute comprises: and analyzing the write-once read-many attribute character string to acquire preset type data. And acquiring a write-once read-many attribute character string through getxattr, analyzing the character string, and acquiring data of three uint64_ t types, wherein the data correspond to grace period time, guard period time and current time respectively. The write-once read-many property string may be, for example, "gram _ period ═ 1621844209, protect _ period ═ 3829364209, and now ═ 1621848238", where gram _ period is the grace period time, protect _ period is the guard period time, and now is the current time.

In some embodiments, said determining whether said file is within a protection period according to said write-once read-many attribute comprises: and carrying out format conversion on the preset type of data to obtain the grace period time, the guard period time and the current time. Continuing with the above example, three agent 64_ t types of data can be converted by date-d commands into: 24 days monday, 16:16:49, 5 months, 2021; 2091, 5, 7, monday, 16:16: 49; 24 days monday, 17:23:58, 5 months, 2021. Namely, the grace period time is 2021, 5, 24, monday, 16:16:49, the guard period time is 2091, 5, 7, monday, 16:16:49, and the current time is 2021, 5, 24, monday, 17:23: 58.

In some embodiments, said determining whether said file is within a protection period according to said write-once read-many attribute comprises: judging whether the current time is greater than the grace period time or not; and in response to the current time being greater than the grace period time, determining whether the current time is less than the guard period time. And if the current time is greater than the grace period time and the current time is less than or equal to the protection period time, returning to true, namely the file is in the protection period. The above example satisfies the above condition, and therefore, the file is in a write-once read-many protection period.

And responding to the file in the protection period, and returning a read-only permission to the client so that the client normally reports errors. In some embodiments, the returning read-only permission to the client so that the client normally reports an error comprises: and giving read-only permission to the permission parameter of the acquisition permission request structure body. If the file is in the protection period, the ACCESS request structure body authority parameter is endowed with READ-only authority (ACCESS3_ READ) and returned to the client.

After the above operations are executed, the file in the write-once read-many protection period is overwritten and additionally written again, and the result is as follows:

[[email protected] acl_0524]#cat file

22

[[email protected] acl_0524]#echo“11”>file

-bash：file：Permission denied

[[email protected] acl_0524]#cat file

22

[[email protected] acl_0524]#echo“11”>>file

-bash：file：Permission denied

[[email protected] acl_0524]#cat file

22

from the above results, it can be seen that the overwrite and the append are performed on the file with the write-once read-many protection period, the content of the file is not changed, and is always "22", and the system reports an error (Permission denied access).

The method comprises the steps that a client performs additional writing or covering writing on a file which is written once and read for multiple times in a protection period, packet capturing is performed at a server (two packet capturing results are the same), and as a result, the client sends three operation word requests of GETATTR, ACCESS and GETATTR to the server, wherein ACCESS returned to the client by the server is RD; the client does not send a WRITE operation word request to the server.

When a client performs additional writing or overwriting on an existing file, the client sends an access request to a server, the server acquires write-once read-many attributes of the file by using the access request, judges whether the file is in a write-once read-many read protection period, returns read-only permission to the access request if the file is in the write-once read-many read protection period, and reports an error if the client receives the read-only permission returned by the server; no write request is sent to the server, and thus no data is written into the file.

The invention further supplements and perfects the functions of the network file system. By the method, the situation that the client does not report errors when an error code is returned to the client through the WRITE in the WORM attribute protection period can be fully considered and solved, the efficiency of processing the client request by the back-end server can be improved, the network data processing capacity is further enhanced, and the flexibility and the availability of the network are improved.

The embodiment of the invention mainly comprises the steps that when a client performs additional writing or overwriting on a file by using echo, the client sends an access request to a server, the server checks whether the file is in a WORM protection period or not by using the access request, if the file is in the WORM protection period, the server returns a read-only permission to the client through the access, the client reports an error after receiving the read-only permission of the access, the write request is not sent to the server, and therefore data are not written into the file any more.

It should be particularly noted that, the steps in the embodiments of the method for overwriting and appending normal error reporting described above can be mutually intersected, replaced, added, and deleted, so that these methods for overwriting and appending normal error reporting, which are reasonably changed by permutation and combination, should also belong to the scope of the present invention, and should not limit the scope of the present invention to the embodiments.

In view of the above object, according to a second aspect of the embodiments of the present invention, there is provided a system for normal error reporting of overwriting and additional writing, including: the sending module is configured to respond to the additional writing or the overwriting of the file and send a permission obtaining request to the server; the acquisition module is configured to respond to the received acquisition permission request and acquire the write-once read-many attribute of the file according to the acquisition permission request; the judging module is configured to judge whether the file is in a protection period according to the write-once read-many attribute; and the execution module is configured to respond to the file in the protection period and return a read-only permission to the client so that the client normally reports errors.

In some embodiments, the obtaining module is configured to: and calling an attribute obtaining function in the static link library to transfer corresponding parameters so as to obtain the write-once read-many attribute character string of the file.

In some embodiments, the determining module is configured to: and analyzing the write-once read-many attribute character string to acquire preset type data.

In some embodiments, the determining module is configured to: and carrying out format conversion on the preset type of data to obtain the grace period time, the guard period time and the current time.

In some embodiments, the determining module is configured to: judging whether the current time is greater than the grace period time or not; and in response to the current time being greater than the grace period time, determining whether the current time is less than the guard period time.

In some embodiments, the obtaining module is configured to: and judging whether the write-once read-many attribute of the file is valid or not.

In some embodiments, the execution module is configured to: and giving read-only permission to the permission parameter of the acquisition permission request structure body.

The embodiment of the invention mainly comprises the steps that when a client performs additional writing or overwriting on a file by using echo, the client sends an access request to a server, the server checks whether the file is in a WORM protection period or not by using the access request, if the file is in the WORM protection period, the server returns a read-only permission to the client through the access, the client reports an error after receiving the read-only permission of the access, the write request is not sent to the server, and therefore data are not written into the file any more.

In view of the above object, a third aspect of the embodiments of the present invention provides a computer device, including: at least one processor; and a memory storing computer instructions executable on the processor, the instructions being executable by the processor to perform the steps of: s1, responding to the additional writing or the overwriting of the file, and sending an authority acquisition request to the server; s2, responding to the received permission acquisition request, and acquiring write-once read-many attributes of the file according to the permission acquisition request; s3, judging whether the file is in a protection period according to the write-once read-many attribute; and S4, responding to the file in the protection period, returning read-only authority to the client so that the client normally reports errors.

In some embodiments, the obtaining the write-once read-many attribute of the file according to the obtaining permission request includes: and calling an attribute obtaining function in the static link library to transfer corresponding parameters so as to obtain the write-once read-many attribute character string of the file.

In some embodiments, said determining whether said file is within a protection period according to said write-once read-many attribute comprises: and analyzing the write-once read-many attribute character string to acquire preset type data.

In some embodiments, said determining whether said file is within a protection period according to said write-once read-many attribute comprises: and carrying out format conversion on the preset type of data to obtain the grace period time, the guard period time and the current time.

In some embodiments, said determining whether said file is within a protection period according to said write-once read-many attribute comprises: judging whether the current time is greater than the grace period time or not; and in response to the current time being greater than the grace period time, determining whether the current time is less than the guard period time.

In some embodiments, the obtaining the write-once read-many attribute of the file according to the obtaining permission request includes: and judging whether the write-once read-many attribute of the file is valid or not.

In some embodiments, the returning read-only permission to the client so that the client normally reports an error comprises: and giving read-only permission to the permission parameter of the acquisition permission request structure body.

The embodiment of the invention mainly comprises the steps that when a client performs additional writing or overwriting on a file by using echo, the client sends an access request to a server, the server checks whether the file is in a WORM protection period or not by using the access request, if the file is in the WORM protection period, the server returns a read-only permission to the client through the access, the client reports an error after receiving the read-only permission of the access, the write request is not sent to the server, and therefore data are not written into the file any more.

Fig. 2 is a schematic diagram of a hardware structure of an embodiment of the above computer device for overwriting and additionally writing normal error reporting according to the present invention.

Taking the apparatus shown in fig. 2 as an example, the apparatus includes a processor 201 and a memory 202, and may further include: an input device 203 and an output device 204.

The processor 201, the memory 202, the input device 203 and the output device 204 may be connected by a bus or other means, and fig. 2 illustrates the connection by a bus as an example.

The memory 202, which is a non-volatile computer-readable storage medium, may be used to store non-volatile software programs, non-volatile computer-executable programs, and modules, such as program instructions/modules corresponding to the method for overwriting and appending normal error reporting in the embodiments of the present application. The processor 201 executes various functional applications and data processing of the server by running the nonvolatile software program, instructions and modules stored in the memory 202, that is, the method for overwriting and appending normal error reporting of the above method embodiment is realized.

The memory 202 may include a storage program area and a storage data area, wherein the storage program area may store an operating system, an application program required for at least one function; the storage data area may store data created according to the use of the method of overwriting and appending normal error reporting, and the like. Further, the memory 202 may include high speed random access memory, and may also include non-volatile memory, such as at least one magnetic disk storage device, flash memory device, or other non-volatile solid state storage device. In some embodiments, memory 202 may optionally include memory located remotely from processor 201, which may be connected to local modules via a network. Examples of such networks include, but are not limited to, the internet, intranets, local area networks, mobile communication networks, and combinations thereof.

The input device 203 may receive information such as a user name and a password that are input. The output device 204 may include a display device such as a display screen.

Program instructions/modules corresponding to one or more methods for overwriting and appending normal error reporting are stored in the memory 202, and when executed by the processor 201, perform the methods for overwriting and appending normal error reporting in any of the above-described method embodiments.

Any embodiment of a computer device implementing the above method for overwriting and appending normal error reporting may achieve the same or similar effects as any corresponding method embodiment described above.

The invention also provides a computer readable storage medium storing a computer program which, when executed by a processor, performs the method as above.

Fig. 3 is a schematic diagram of an embodiment of a computer storage medium for overwriting and additionally writing normal error reporting according to the present invention. Taking the computer storage medium as shown in fig. 3 as an example, the computer readable storage medium 3 stores a computer program 31 which, when executed by a processor, performs the method as described above.

Finally, it should be noted that, as one of ordinary skill in the art can appreciate that all or part of the processes of the methods of the above embodiments can be implemented by a computer program to instruct related hardware, and a program for overwriting and appending the methods of normal error reporting can be stored in a computer readable storage medium, and when executed, the program can include the processes of the embodiments of the methods as described above. The storage medium of the program may be a magnetic disk, an optical disk, a Read Only Memory (ROM), a Random Access Memory (RAM), or the like. The embodiments of the computer program may achieve the same or similar effects as any of the above-described method embodiments.

The foregoing is an exemplary embodiment of the present disclosure, but it should be noted that various changes and modifications could be made herein without departing from the scope of the present disclosure as defined by the appended claims. The functions, steps and/or actions of the method claims in accordance with the disclosed embodiments described herein need not be performed in any particular order. Furthermore, although elements of the disclosed embodiments of the invention may be described or claimed in the singular, the plural is contemplated unless limitation to the singular is explicitly stated.

It should be understood that, as used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly supports the exception. It should also be understood that "and/or" as used herein is meant to include any and all possible combinations of one or more of the associated listed items.

The numbers of the embodiments disclosed in the embodiments of the present invention are merely for description, and do not represent the merits of the embodiments.

It will be understood by those skilled in the art that all or part of the steps for implementing the above embodiments may be implemented by hardware, or may be implemented by a program instructing relevant hardware, and the program may be stored in a computer-readable storage medium, and the above-mentioned storage medium may be a read-only memory, a magnetic disk or an optical disk, etc.

Those of ordinary skill in the art will understand that: the discussion of any embodiment above is meant to be exemplary only, and is not intended to intimate that the scope of the disclosure, including the claims, of embodiments of the invention is limited to these examples; within the idea of an embodiment of the invention, also technical features in the above embodiment or in different embodiments may be combined and there are many other variations of the different aspects of the embodiments of the invention as described above, which are not provided in detail for the sake of brevity. Therefore, any omissions, modifications, substitutions, improvements, and the like that may be made without departing from the spirit and principles of the embodiments of the present invention are intended to be included within the scope of the embodiments of the present invention.