JPS6053327B2 - Item search method - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an operating system for an electronic computer, and relates to an item search method for extracting the start address of an item in various control tables.

The operating system has various control tables in main memory. For example, in an operating system that has many users who use a computer from many terminals and processes the processing requests of each user in a time-sharing manner, items of a size determined for each user are Prepared in storage device. In each item, a user number, user name, verification code, usage permission conditions, billing fee, etc. are recorded. When the number of users increases, the operating system rents out storage area as one table for each five items, for example. A pointer area of a specified length is secured at a specified position in each table, and the start address of a newly added table is stored in the pointer area of the last table, so that each table can be inherited in turn. go.

Conventionally, the following method has been used to find the starting address of the item having the target user number from the table configured as described above.

For example, when you want to modify the billing fee for the item No. 13'' of the user number (the following items are focused on and the user number is called the item number), the first address from the first address of the first table (first table) is Find the table.

Since items No. 21 to No. 5 are registered, the pointer is read and the start address of the next table is obtained.

3 Since 6 to 10 items are registered in this second table, read the pointer again to obtain the start address of the next table.

4. Since the items 11th to 1st are registered in this third table, the area for two items is added to the starting address of this table to obtain the starting address of the 11th table.

Below, the billing fee written in the specified position of the 11th item is corrected.

There are more than a few types of registration tables in an operating system, and the attributes that make up each table, namely the number of items in one table, the size of the items, the position of the pointer, and the length of the pointer, are different. There is.

Therefore, a request source using the items in each table must individually store the attributes constituting the registration table and extract the starting address where the item exists from the specified item number.

The object of the present invention is to overcome the above-mentioned drawbacks, and the purpose is to provide a computer with an operating system that has a group of registration tables sequentially connected by pointers and containing certain items. The address, the number of items in each table, the length of each item, the position of the pointer that connects each table in each table,
A table attribute storage means for storing the length of a pointer and an address calculation means for calculating the start address of the item from the item number are provided, and when an item number is specified, the address calculation means This was achieved by referring to the item number and calculating the start address of the item with that item number.

This invention will be explained in detail below with reference to the drawings.

FIG. 1 shows an example of a registration table existing in a storage device, and FIG. 2 is a configuration diagram of an embodiment of an item search device based on the present invention. In FIG. 1, 11 to 1n are registration tables, each consisting of a continuous storage area, and 11a to 1n.
1e, 12a~12e, 13a~13e, 1m~1ne
are each item with a length of 11 bytes registered in the registration table, 11p, 12p, 13p, . is a 12-byte pointer in which the start address of the next registration table is stored.

In FIG. 2, 2 is a table attribute storage means, 21 is the address of the first registration table, 22 is the number of items included in one registration table, and 23 is each! The length of the item, 24 is the pointer position in the registration table, and 25 is the length of the pointer. In the figure, 3 is an item search device, and 4 is a request source.

31 is a table address register, 32 is an item number register, 33 is an item length register, 34 is a pointer position register, 35 is a pointer length register, 41 is an attribute address register, 42 is an item number register, 43 is an item address register, 51 is a quotient register, 52 is a remainder register,
61 is a pointer reading circuit, 62 is a subtraction circuit, 71 to 74
is an arithmetic logic circuit, and 81 to 82 are AND gates.

In FIG. 1, each registration table 11-1n exists in the main memory, and items 11a-11e, 1
2a to 12e, 13a to 13e, and 1na to 1ne are one processing unit and consist of a storage area of 11 bytes. In addition, in this example, 5 items are registered per registration table, and from the top address of each registration table (11X5
) Byte position ■ This pointer position exists. The pointer 11p of the registration table 11 contains the start address of the registration table 12;
p contains the start address of the registration table 13, and the subsequent registration tables up to the last registration table 1n are successively connected by the pointer of the immediately previous registration table.

The length of this pointer is 12 bytes. In Figure 2, when various programs in the operating system need the address in the registration table where the item exists based on the number of the item that has become their processing target, those programs act as request source 4. , requests the item search device 3 to calculate the item address.

At this time, the request source 4 sends the table attribute storage means 2 secured in the main memory to the attribute address register 41, and also sends the number of the item whose address therein is desired to be calculated to the item number register 42. The item search device 3 learns the location of the table attribute storage means from the value of the attribute address register 41, and sequentially reads the contents into its own registers.

Read the address 21 of the first registration table into the table address register 31, and read the number of items 22 into the number of items register 3.
2, the item length 23 is read to the item length register 33, the pointer position 24 is read to the pointer position register 34, and the pointer length 25 is read to the pointer length register 35. First, the value of the item number register 42 is divided by the value of the item number register 32 by the arithmetic logic circuit 71, and the quotient resulting from the division is stored in the quotient register 51 and the remainder in the register 52.

The arithmetic logic circuit 72 calculates the product of the value obtained by subtracting 1 from the value found in the remainder register 52 and the value in the item length register 33, and determines the value at which the target item in the registration table is located from the top of the registration table. It is calculated and sent to the arithmetic logic circuit 73. On the other hand, if the value of the quotient register is ゜゜zero, the AND gate 81 is opened and the value of the head address register 31 is sent to the arithmetic logic circuit 73.

Therefore, the arithmetic logic circuit 73 adds the top address of the registration table and the distance from the top of the table and outputs the address of the desired item to the item address register 43. If the value of the quotient register 51 is not zero in the division result of the arithmetic logic circuit 71, the AND gate 82 opens, and if the table address register 31 is selected, the value indicating the pointer position in the registration table in the pointer position register 34 is opened. , are added by the arithmetic logic circuit 74, and the address where the pointer is stored is determined. Based on the address where this pointer is stored and the length of the pointer indicated by the pointer length register 35, the pointer reading circuit 61 reads the start address of the next successive registration table into the table address register 35.
At the same time, a signal is sent to the subtraction circuit 62 to subtract "1" from the value of the quotient register 51.

If the value of the quotient register 51 is not ゜゜zero, the AND gate 82 is opened again, and the operation of the arithmetic logic circuit 74 and the processing of the pointer reading circuit 61 are repeated until the value of the quotient register 51 becomes zero, and the registration table is read one after another. The start address of is obtained from the table address register 31. Quotient register 51
When the value of becomes "゜0゛2," the value of the table address register 31 obtained at that time is the start address of the registration table containing the desired item.The arithmetic logic circuit 73 reads the quotient register 5.
When the value of 1 becomes zero, the head address of the desired registration table is received from the table address register 31 via the AND gate 81, and the address from the head of the table of the desired item obtained in the above procedure is sent to the arithmetic logic. It receives it from the circuit 72, adds both values, stores the address of the desired item in the item address register 43, and outputs it to the request source 4.

In the above explanation, the arithmetic logic circuit is shown for each operation to make it easier to understand, but in reality, it is sufficient to have one arithmetic logic circuit, and the item search device itself can also be realized by software. It is possible.

In the above explanation, the position of the pointer in the registration table and the length of the pointer are stored in the table attribute storage means, but it is possible to fix the position of the pointer in the registration table for all registration tables. Placing a pointer at the beginning of the table allows the position of the pointer to be omitted in the table attribute storage means, and the length of each pointer is constant for all registered tables.

For example, if the length of each pointer is one word, the length of the pointer can be omitted in the table attribute storage means. In the above explanation, the requester can specify a specific item number and have the address calculated, so if you want to process all items in order, remember the serial number of the item number and add it. By issuing an item address conversion request to the item search device while increasing the number of items in order, each item in the registration table can be processed in order.

As explained above, in an operating system having a group of registration tables sequentially connected by pointers and containing a certain number of items, the present invention provides means for storing the attributes of the registration table, Since an address calculation means for calculating the address, that is, an item search device is provided, and the start address of the item can be easily found from the item number, there is no need for each program in the operating system to memorize table attributes. It is no longer necessary for each user to have a program that calculates the start address of an item from the item number.

[Brief explanation of the drawing]

FIG. 1 is an example of a registration table, and FIG. 2 is a configuration diagram of an embodiment of the item search device. In FIG. 1, 11-1n are registration tables, 11a-1
1e, 12a-12e, 13a-13e, 1r1a-1
ne is an item, and 11p, 12p, and 13p are pointers. In FIG. 2, 2 is a tape attribute storage means, 3 is an item search device, and 4 is a request source. 21 is the address of the first registration table, 22 is the number of items, 23 is the length of the item, 24
is the pointer position, and 25 is the length of the pointer. 31 to 35 are registers for storing each term in the table attribute storage means, 41 to 43 are interface registers with the request source, 51 to 52 are working registers, 61 is a pointer reading circuit, 62 is a subtraction circuit, 71 to 74 is an arithmetic logic circuit, and 81 to 82 are AND gates.

Claims (1)

[Claims] 1. In an item search method for a computer that has a group of registration tables that are sequentially linked by pointers and contain a certain number of items, the first address of the first linked registration table, the number of items in each table, and each item are table attribute storage means for storing the length of the table, the position of the pointer that inherits each table in each table, and the length of the pointer; address calculation means for calculating the start address of the item from the item number; and storage for storing the item number. When an item retrieval request is specified, the item storage means is updated, and the address calculation means refers to the table attribute storage means to calculate the starting address of the item having the item number. An item search method characterized by: