JPH03223923A - Control system for input of unfixed byte length character - Google Patents

Abstract

PURPOSE:To process a text code in a simple and effective way by providing a text code generating means which inserts a control character for the generation of the text code and a character attribute identifying means which identifies the attribute defined to each character of the text code. CONSTITUTION:A text code generating means 1 produces a text code with the addition of a control character having the byte length of an unchanged character when the byte length of the characters constituting a character string is changed halfway of the character string. A character attribute identifying part 2 controls the 1-byte character attribute information 5 and the 2-byte character attribute information 6 which are stored in a storage area 3. For these character attribute information, the byte code tables 7-10 are prepared. Thus, the byte code tables are turned into a hierarchical structure in response to each byte of characters for the control of the attribute set to each character of each byte length. Thus, it is not required to process a text code which incorporates the characters of different number of bytes.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an indefinite byte length character input control method for processing character strings in which characters of different byte lengths coexist in a computer system.

(Prior Art) In recent information processing systems, processing of Japanese data has become essential. However, various problems have arisen in processing characters in Japanese data that cannot be expressed in one byte. These various problems are due to the expansion of the 1-byte code system, which uses alphanumeric characters as the standard, by adding the Japanese code system, which is expressed using 1 character and 2 bytes. For example, when processing a string in which a 2-byte character appears next to a 1-byte character, there are issues such as how to notify the system processing the string that the byte length representing one character has changed. , ASCII code °1
There are problems such as the need to recognize ゛ and °l' in the JIS vague character code as the same number. These problems have a great impact on systems that process text codes, such as language processing systems.

FIG. 2 is a diagram showing the configuration of a conventional character input control system of indefinite byte length. In the text code 208 generated by the text code generation unit 201, a 2-byte character string portion in the text code 208 is surrounded by two control characters with a fixed byte length indicating the start or end of the 2-byte character. For example, in the character string °^BCJapanese

Control characters <KT> and <KO> representing the start and end of double-byte characters, respectively, are inserted between Xo. These two control characters consist of 2 bytes and have hexadecimal codes of 3F75.3F76, respectively.

The 1-byte input processing unit 202, which is given the text code 208 generated by the text code generation unit 201, supplies the 1-byte character with the given text code 208 to the 1-byte character attribute identification unit 204. The 1-byte character attribute identification unit 204 looks up the 1-byte code table 206 using the given character code, and obtains the attribute bit table 209 in which attribute information for the 1-byte character is stored. Here, if the 1-byte input processing unit 202 finds a 1-byte code of 3F, it will read the next 1 byte, and if it is 75, it will transfer control to the 2-byte input processing unit 203, otherwise it will continue to write 1 byte. Perform input processing.

When control is transferred to the 2-byte input processing unit 203, the 2-byte character is given to the 2-byte character attribute identification unit 205, and the 2-byte code table 207 is looked up using the 2-byte code to create the attribute bit table 210 for the 2-byte character. obtain. Since the control character <KO> that indicates the end of a 2-byte character string is 2 bytes long, the 2-byte input processing unit 203 can identify the control character <KO> without performing any special processing. KO> is found, control is returned to the 1-byte input processing unit 202.

Character attributes were identified as follows. for example,
To represent the presence or absence of 32 types of attributes using 8-bit characters, prepare a bytecode table with 256 elements and 4 bytes per element, and if the character code for '1° is 241. Turn ON the bit representing the numeric attribute in the 241st attribute bit table of the bytecode table.
' to do, and so on. For 2-byte characters, the table size is set to 65536 and processed.

(Problem to be Solved by the Invention) In the conventional character input control method of indefinite byte length described above, two
Because the byte length of the two control characters that are added before and after a byte character to indicate the start or end of a 2-byte character is fixed, a system that processes a text code containing characters of varying number of bytes will not be able to process 1-byte characters. While inputting or inputting double-byte characters, it was necessary to deal with a control character whose byte length was different from the character being processed. Furthermore, the text code processing system requires two input processing sections, a 1-byte character input processing section and a 2-byte character input processing section, making the processing system complex and inefficient.

As described above, there are problems that need to be solved in the conventional character input control method of indefinite byte length.

(Means for Solving the Problems) The present invention provides variable byte length character input control in a computer system that processes character strings in which English characters expressed in one byte and Japanese characters expressed in multiple bytes coexist. In this method, for each character of different byte length mixed in a string, it is shown that the byte length of the character that has the same byte length and that follows in the string changes, and the byte length of the character that follows it. Control characters and character attribute information that manages the attributes of each character for each byte length are defined by layering the byte code table corresponding to each byte that constitutes the character, and characters with different byte lengths coexist. Receive a character string, and at a virtual position between characters of different byte lengths in the string, find out how many bytes is the byte length of the character that has the same byte length as the previous character and follows the character. text code generation means for generating the text code by inserting the control character indicating the text; character attribute identification means for identifying character attributes defined in .

(Example) Next, the present invention will be explained with reference to the drawings.

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

When the byte length of the characters constituting the input character string changes midway through the input character string, the text code generation unit 1 generates a text code by adding a control character that is the byte length of the character before the change. do.

Character attribute identification section 2 manages 1-byte character attribute information 5 and 2-byte character attribute information 6 in storage area 3 . Each character attribute information has several bytecode tables 7.8, 9.10, and the attributes for each character of each byte length are hierarchically arranged by the bytecode tables corresponding to each byte of that character. Managed. The bytecode table corresponding to the least significant byte of each character contains an attribute bit table indicating attributes for that character, or a bytecode table for the most significant byte of other character attribute information that indicates that the byte length of the character changes. A pointer to is stored.

Register CT4 points to the byte code table of the most significant byte of character attribute information for the length of the character currently being input.The initial value of register CT4 is the pointer value to byte code table 7 of 1-byte character attribute information 5. It is.

Consider a bytecode table in which 1 byte is 8 bits and each element is 4 bytes.

Here, the code for the 1-byte control character <2S> indicating a change from a 1-byte character to a 2-byte character is 3F, and the code for the 2-byte control character <IS> indicating a change from a 2-byte character to a 1-byte character. Let be 3F76. At this time, the text code generating section 1 generates the text code shown in FIG. 4 for the character string 123456'. Here, '1', '2', '5', and °6' are 1-byte characters, and in hexadecimal numbers Fl, F2, . Assume that the code is F5F6. '3' and '4' are double-byte characters, and their codes are respectively 7BF3.7 in hexadecimal.
Suppose it is 8F4. Between 2° and °3° and '4'
and 5", control characters <28> and <IS> are inserted, respectively. Therefore, the control characters with the same byte length as the character immediately before and after the 2-byte length character change. All control characters that indicate that the byte length of a character changes when a character is inserted are expressed by the byte length of the character currently being input, so control characters can be identified by the byte length of the character currently being input. .

Next, processing of the text code shown in FIG. 4 generated by the text code generation section 1 will be explained. FIG. 5 is a flowchart showing the processing of the character attribute identification section 2. The character attribute identification unit 2 first assigns the contents of the register CT4 to the register P15 (step 501). At this time, a pointer value to the byte code table 7 of the 1-byte character attribute information 5 is stored in the register CT4, and the pointer value is assigned to the register P15. Then, one byte of the text code is read and assigned to register Q16 (step 502). Then, the character ``1'' is stored in register Q16.
' character code F1 is passed, and the contents of the F1-th element of the bytecode table 7 pointed to by the register CT4 are assigned to the register P15 (step 503) (see FIG. 7(a).
)).

The content of each bytecode table element is a pointer value to another bytecode table or a bytecode for the most significant byte of attribute information in an attribute bit table or other character when the character is a control character indicating a change in byte length. Any pointer value to a table. These are identified as follows. The size of each bytecode table is constant and the number of bytes is a multiple of 4, so by arranging them in storage area 3, the lower two bits of the first address of each bytecode table can be set to O. can. Therefore, if the least significant bit of an element in a bytecode table is the 0th bit and the most significant bit is the 31st bit, as shown in Figure 6, if the value of the 1st and 0th bits is 00, the data is transferred to another bytecode table. pointer value (601), if 01, attribute bit table (602),
If it is 11, it can be identified as the value obtained by adding 3 to the pointer value to the byte code triple for the most significant byte of other character attribute information.

The byte length of the character currently being input is 1, so the content of register P15 is not a pointer value to another bytecode table, and the character is 1' and is not a control character, so the contents of register P15 are Each attribute is processed according to the contents of the given attribute bit table 12 (steps 504, 505, and 506) (processing is performed as a number based on the meaning of the character 1°). Next, the process returns to step 501, and the same process is performed on the 2° character. For the control character 2S, the contents of the 3Fth byte code table 7 of the 1-byte character attribute information 5 are obtained in the register P15 in step 503. Since this content is the value obtained by adding 3 to the pointer value to the bytecode table 8 for the upper byte of the 2-byte character attribute information 6, the process moves to step 507 via steps 504 and 505. Here, the value obtained by subtracting 3 from the contents of register P15 is assigned to register CT4 (step 507), and the process returns to step 501.

Hereinafter, the register CT4 holds a pointer value to the bytecode table for the upper byte of the 2-byte character attribute information 6. 2 of 3' obtained from text code 11
Get the upper byte of the character code of the byte and register CT
The 7Bth element of the bytecode table 8 pointed to by 4 stores a pointer value to another bytecode table 9, so in step 504, the process moves to step 502, and for the lower byte, the lower byte is stored. The attribute bit table 14 is obtained from the contents of the F3rd bytecode table 10, and each attribute process is performed (step 506).
Figure 7(b)). The character °4' is the same as 3'. The control character IS is a control character that indicates the start of a 1-byte character consisting of 2 bytes, and the 76th content of the byte code table 9 pointed to by the 3F-th element of the byte code table 8 pointed to by register CT4 contains 1-byte character attribute information. A value obtained by adding 3 to the pointer value to the byte code table 7 of 5 is set, and in step 507, the register CT4 is again in the state of identifying 1-byte characters. Thereafter, the characters °5° and '6' are input and processed in the same way as °1° and °2°.

The embodiment described above was limited to 1-byte characters and 2-byte characters, but in a system that handles characters of 1 to N bytes, a control character indicating a change in the byte length of each character is assigned to each character. The present invention can be easily applied by defining N-1. For example, in a system that handles 1- to 3-byte characters, two 1-byte control characters, 1
It is sufficient to define six control characters: two 2-byte control characters indicating change to byte and 3-byte characters, and two 3-byte control characters indicating change to 1-byte and 2-byte characters. Furthermore, although the present invention appears to require a large number of bytecode tables, in reality there are only a limited number of characters that have special attributes, so there are many bytecode tables with exactly the same content. Tend. Therefore, the problem of the need for a large number of bytecode tables can be solved by preparing only one bytecode table so that it can be referenced from different locations.

(Effects of the Invention) As explained above in detail, the variable byte length character input control method of the present invention allows the text code processing system to input 2-byte characters even when it is inputting 1-byte characters. There is no disruption in the processing of control characters. Further, it is not necessary to prepare an input processing section for 1-byte characters and an input processing section for 2-byte characters in the text code processing section, and a simple and efficient text code processing section can be realized.

The present invention has the above effects.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a block diagram showing a conventional variable byte length character input control method, and FIG. 3 is a block diagram showing the text generated by the conventional text code generation unit 201. FIG. 4 is a diagram showing the text code generated by the text code generation section 1 of the present invention. FIG. 5 is a flowchart showing the processing of the character attribute identification section 2 of the present invention.
The figure shows the types of elements of the bytecode table of the present invention, and FIG. 7 shows the attribute bit table hierarchically managed by the bytecode table of the present invention. 1.201...Text code generation section, 2...Character attribute identification section, 3...Storage area, 4...Register CT
, 5... 1-byte character attribute information, 6... 2-byte character attribute information, 7, 8, 9.10... Byte code table, 11,208... Text code, 12.13
゜14.209.210...Attribute bit table, 1
5...Register P, 16...Register Q, 202.
...1-byte input processing section, 203...2-byte input processing section, 204...1-byte character attribute identification section, 205.
... 2-byte character attribute identification section, 206... 1-byte code table, 207... 2-byte code table,
601, 602, 603... Bytecode table 6

Claims (1)

[Claims] In an indefinite byte length character input control method in a computer system that processes character strings in which English characters expressed in one byte and Japanese characters expressed in multiple bytes coexist, For each character of different byte length, the character is composed of a control character that has the same byte length as the character and indicates that the byte length of the character that follows in the string changes and the byte length of the character that follows it. The byte code table corresponding to each byte is hierarchically defined, and the character attribute information that manages the attributes for each character for each byte length is defined. Character attribute identification means receives characters of different byte lengths and a text code generated by the text code generation means, and identifies character attributes defined for each character of the text code by referring to the character attribute information. An indefinite byte length character input control method characterized by having the following.