JPH09244977A - Communication management system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To secure a normal communication function without damaging data by the subscribing of the other data to a transmission/ reception buffer even for simultaneous transmission/reception requests from plural applications. SOLUTION: A communication management module 4 is provided between the applications 11 -1N and a communication interface 2A. For simultaneous data transmission requests from the respective applications, communication control for putting the transmission requests on hold, performing the transmission/reception of the data through a buffer to the application to which, a communication issuing right is supplied and shifting the issuing right to the other application whose request is put on hold at the time of receiving the release informing of the issuing right by data transmission/reception completion from the application is performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication management system for allowing a computer capable of multitasking to communicate with the outside using a non-reentrant communication interface.

[0002]

2. Description of the Related Art When a computer communicates with the outside,
Each application installed in the computer can call a communication module whose procedure is to be called, and can perform communication by a simple and simple procedure.

In a computer capable of multitasking, when a multi-window display for each application is made and communication is performed with a different party (computer etc.) for each application, a data transmission / reception request is asynchronously issued from each application. Therefore, as shown by functional blocks in FIG. 4, the communication module 2 called from each of the applications 1 ₁ to 1 _N can operate in a re-entrant environment.

Further, the communication module 2 has transmission / reception buffers 3 _{1 to} 3 _N for each application,
Data transmission / reception requests from each application can be accepted asynchronously.

[0005]

When a re-entrant or a single transmission / reception buffer is used as a communication module of a computer capable of executing multitasking, each application makes a transmission / reception request at random. Before communication using data is completed,
Other data may be overwritten in the send / receive buffer and normal communication may not be possible.

Further, when the computer is operated in an environment with a small memory capacity and a transmission / reception buffer having a large capacity is provided, the processing speed of the entire computer decreases due to the data swap between the memory and the transmission / reception buffer.
This is also the case when the number of applications for multitask execution increases even if the transmission / reception buffer has a small capacity.

It is an object of the present invention to provide a communication interface in which a computer capable of executing multitasking cannot re-enter and 1
When communicating with the outside using one send / receive buffer,
An object of the present invention is to provide a communication method that eliminates the damage of communication data and reduces the decrease in the processing speed of a computer.

[0008]

SUMMARY OF THE INVENTION The present invention is a method for a computer capable of multitasking to communicate with the outside using a non-reentrant communication interface and a send / receive buffer. A communication management module is provided between the interface and the communication management module, in response to an asynchronous data transmission request from each application, suspends the transmission request if data transmission / reception of another application is in process. Returns the pending status to the application, and when the data transmission / reception by another application is not in process, gives the application the right to issue data transmission / reception, and the communication management module sends the data transmission / reception from the application to which the issue right is given. Upon request, the communication interface When the transmission / reception is completed, the communication management module gives a completion message to the application when the transmission / reception is completed, and the communication management module It is characterized in that the issuing right is transferred to the request pending application.

[0009]

FIG. 1 is a block diagram for communication showing an embodiment of the present invention. 4 is different from FIG. 4 in that it has a non-reentrant communication interface 2A, and this communication interface 2A and each application 1 ₁ to 1 _N
The point is that the communication management module 4 is provided between the two and the one transmission / reception buffer 3 for temporarily storing the transmission / reception data.

The communication management module 4 is software for controlling data transmission / reception requests from the respective applications 1 ₁ to 1 _{N. Since} the communication interface 2 A cannot re-enter, the data transmission / reception buffer 3 has a transmission buffer and a reception buffer. Have only one set.

Each of the applications 1 ₁ to 1 _N does not directly call the communication interface 2 A, but calls the communication management module 4 to exchange data with the outside.

The data transmission / reception buffer 3 accepts a data transmission / reception request from one application at a certain point because the communication interface 2A cannot be re-entered. The communication management module 4 gives one of the applications the right to issue a data transmission / reception request (issue right), and accepts only data transmission / reception from the application. Hereinafter, the data transmission / reception processing by the communication management module 4 will be described in detail with reference to FIGS. 2 and 3.

(1) Acquisition of issue right of data transmission / reception request (FIG. 2).

In FIG. 2, the connection between the communication management module 4 and the communication interface 2A is shown by WindowsSo.
The case of using ccket is shown, and the portion indicated by the broken line block is not included in the communication management module.

For communication between each of the applications 1 ₁ to 1 _N and the communication management module 4 and the communication interface 2A, the socket is initialized by an initialization request by the application _IX . Further, the communication between the communication management module 4 and the communication interface 2A is performed by the application 1
Data transmission is performed by the procedure of socket creation request and its creation by data transmission request from _X , connection establishment request and its processing, message issuance request and message issuance by successful connection, and data transmission.

[0016] Here, the acquisition of the application 1 _X publishing rights for communicating with the outside, as shown in the process 4A portion of the communications management module 4, the acquisition of the application 1 _X issued rights to the communication management module 4 Request and issue issuance right from the communication management module. The granting of this issue right differs as follows depending on whether or not data is being transmitted / received.

(1 ₁ ) During data transmission / reception.

When there is a request from the application 1 _X to acquire an issuance right, the communication management module 4 suspends the request of the application 1 _X that has issued the issuance right request if data transmission / reception of another application is in process. The status of pending issuance right request is returned to the application 1 _X as well as the fact that it has been set. When the application 1 _X cannot acquire the right to issue, it does other processing until the right to issue is granted to itself.
Wait for issuance right. (1 ₂ ) When data is not being sent or received.

When the application 1 _X issues a request to obtain the right to issue, the communication management module 4 checks whether another application has the right to issue the right to issue. Give _X the issue right.

(2) Request for data transmission / reception.

Application 1 that has acquired the issue right
_{The X} stores the transmission data in the transmission data area in the common buffer 3 (creates the transmission data), then requests the communication management module 4 for data transmission, and the communication management module creates a socket with the communication interface 2A. Send data. During this time application 1 _X
Waits for a data reception completion message from the communication management module 4.

Further, when the application 1 _{X which} has acquired the issue right receives data from the outside, as shown in FIG. 3, the received data by Windows Socket is received in the common buffer 3 between the communication management module 4 and the communication interface 2A. The data is stored in the reception data area, the communication management module 4 notifies the application 1 _X of the reception completion, and the application 1 _X goes to get the reception data in the buffer 3.

The transmission and reception of these data are repeated until the required data can be transmitted or received.

(3) Abandonment of issuing right.

When the data transmission / reception of its own application is completed, the application having the issuance right notifies the communication management module 4 of the release of the issuance right as shown in the case of the completion of reception in FIG. When notified of the release of the issuance right, the communication management module 4 transfers the issuance right to another application requesting the issuance right of the data transmission / reception request.

(4) Change of issuing permission application.

The communication management module 4 changes the application to which the issuance right is given when a certain data transmission / reception ends and the issuance right from the application is released. It should be noted that on the operating system (OS) in which the applications run, the recognition code is given to all the applications running at that time.

When the issuing right is abandoned, the communication management module 4 increments (+1) the recognition code of the application. When the application with this new identification code is currently holding the issuance right, send a message to the application to receive the issuance right request,
A request for data transmission / reception is received from the application.

If the application having the new recognition code is not holding the issuance right, the communication management module 4 further increments the recognition code to check whether the application having the recognition code is holding the issuance right.

As described above, by incrementing the recognition code, it is sequentially checked whether or not the issuance rights are pending for all applications, and the issuance-permitted applications are changed in ascending order for each application. If there is no request from all applications, set the recognition code before the change again.

[0031]

As described above, according to the present invention, a communication management module is used as a communication interface for a multi-task executable computer to communicate with the outside using a non-reentrant communication interface and one transmission / reception buffer. It is provided between the application and the application, and this communication management module enables sequential communication control by assigning and releasing the issuing right even for asynchronous communication requests from each application, so that simultaneous transmission / reception requests from multiple applications are possible. Also, the normal communication function can be secured without the data being damaged by overwriting other data in the transmission / reception buffer.

Further, only one transmission / reception buffer is required, and even when the computer is operated in an environment where the application memory capacity is small, there is little chance of swapping data between the memory and the transmission / reception buffer, and the processing speed of the entire computer is reduced. There is nothing to do.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a procedure for acquiring an issuance right and transmitting data according to the embodiment.

FIG. 3 is a procedure for releasing an issuance right with data reception in the embodiment.

FIG. 4 is a conventional block diagram.

[Explanation of symbols]

1 ₁ , 1 _N ... Application 2, 2 A ... Communication interface 3, 3 ₁ , 3 _N ... Send / receive buffer 4 ... Communication management module

Claims (1)

[Claims] 1. A method of communicating with an external device using a multi-task executable computer using a non-reentrant communication interface and a transmission / reception buffer, wherein a communication management module is provided between an application of the computer and a communication interface. The communication management module, in response to an asynchronous data transmission request from each application, if the data transmission / reception of another application is being processed, suspends the transmission request and sets the status of the request pending to the application. In response, when the data transmission / reception by another application is not in process, the data transmission / reception issuance right is given to the application, and the communication management module is connected to the communication interface by the data transmission / reception request from the application to which the issuance right is given. Buff When the transmission / reception is completed, the communication management module gives a completion message to the application, and when the communication management module receives a release notification of the issuance right by the data transmission / reception completion, the request pending application A communication management method characterized by transferring the issuance right to.