Space conversion function

(a) Specification configuration

For details about the specification configuration, see G.1(3)(b) Specification configuration.

(b) Space conversion function (p_rdb_conv_space)

Function

The function converts spaces according to the specified conversion type as follows:

Single-byte space double-byte space:: Converts two consecutive single-byte spaces in a character string to one double-byte space.

Double-byte space single-byte space:: Converts each double-byte space in a character string to two single-byte spaces.

The function converts spaces in the character string indicated by srcp and stores the conversion result in destp. The following table shows the combination of stype and flags arguments and the conversion type:

stype (data type)	flags (conversion type)
stype (data type)	Single-byte space double-byte space	Double-byte space single-byte space
NCHAR	Checks two bytes at a time from the top and converts any two consecutive single-byte spaces to a double-byte space.^* The function does not convert any isolated single-byte space.	Checks two bytes at a time from the top and converts any double-byte space^* to two single-byte spaces.
NVARCHAR
MCHAR	Results in an error.	Checks each character code from the top and converts any double-byte space^* to two single-byte spaces.
MVARCHAR	Results in an error.

^* The function treats the value specified in the ncspace argument as the character code for double-byte space.

Header files

#include<pdauxcnv.h>: This header file is required to use the space conversion function.

#include<pdbsqlda.h>: This header file lets you use macros (with a name beginning with PDSQL_) to specify a data type code. If the data type code is to be retrieved from a data dictionary table, this header file is not necessary.

Format

int p_rdb_conv_space(char            *srcp,
                     unsigned char   stype,
                     unsigned int    srcl,
                     char            *destp,
                     unsigned char   ncspace[2],
                     int             flags);

Arguments

srcp (input): Specifies the start address of the character string storage area.

stype (input)

Specifies the data type before conversion. Specifiable data types are as follows:

Macro name	Data type
PDSQL_NCHAR	NCHAR
PDSQL_NVARCHAR	NVARCHAR
PDSQL_MCHAR	MCHAR
PDSQL_MVARCHAR	MVARCHAR

srcl (input): Specifies the length of the character string specified in srcp. For a variable-length character string, specify the length of the actual character string (in bytes) that is stored in the area indicated by srcp.

destp (output): Sets the start address of the character string storage area after conversion. Allocate this area indicated by destp on the side that calls the space conversion function.

ncspace (input): Specifies a two-byte area that contains the double-byte space character for the national character code used in the HiRDB server. For the double-byte space characters that can be specified in ncspace, see Table G-4 Double-byte space characters specified in ncspace.

flags (input)

Specifies the conversion type. Available conversion types are as follows:

Macro name	Conversion type
p_rdb_HALF_TO_FULL_SPACE	Single-byte space double-byte space
p_rdb_FULL_TO_HALF_SPACE	Double-byte space single-byte space

Return values

data type: int

p_rdb_RC_RTRN(0): Normal termination.

p_rdb_RC_ERRINVF(-8): Invalid flags argument

p_rdb_RC_ERRTYPC(-9): Invalid data type

Notes

The National Language Support (NLS) facility provided by the OS is used to convert double-byte spaces into single-byte spaces. Therefore, before invoking the space conversion function, you must use the setlocale function to set an appropriate locale to the LC_CTYPE or LC_ALL category. Additionally, for a Windows UAP, a Linux UAP with a character code type of SJIS, or a UAP with a character code type of CHINESE, you must invoke the p_rdb_set_lang function before invoking the space conversion function. For details about the p_rdb_set_lang function, see G.4 Character code type specification function.
If the character code type of the character string indicated by the srcp argument contradicts the locale specified by the setlocale or p_rdb_set_lang function, the operation cannot be guaranteed.
Operation is guaranteed if the data input area is the same as the data output area, or if the output area is located before the input area and the latter half of the output area overlaps the first half of the input area.
Be sure to specify an appropriate value in srcl because the function does not check the length of a character string for any error.
The function uses 0x20 as the character code for a single-byte space and the character code specified in the ncspace argument as the character code for a double-byte space.
The data types that can be specified for input are NCHAR, NVARCHAR, MCHAR, and MVARCHAR.
For a variable-length character string, the function references srcl to determine the length of character string to be converted. Specify the length without the real length section in the srcl argument.
The real length section of a variable-length character string remains unchanged after space conversion.
If the character code type is Unicode, the operation of this function cannot be guaranteed. If the character code type is Unicode, use the p_rdb_conv_space_utf8 function. For details on this function, see (c) Space conversion function (p_rdb_conv_space_utf8).

(c) Space conversion function (p_rdb_conv_space_utf8)

Function

This function converts double-byte spaces into single-byte spaces when the character code is Unicode (UTF-8). It converts each double-byte space inside a character string into two single-byte spaces.

This function applies space conversion to the space characters inside the character string indicated by srcp. The conversion result is stored in destp and the character string length following the conversion is stored in destl.

The following table shows the combinations of the stype and flags arguments, along with conversion details.

stype (data type)	flags (conversion type)
stype (data type)	Single-byte spaces -> Double-byte spaces	Double-byte spaces -> Single-byte spaces
MCHAR	An error occurs.	Character codes are checked from the beginning, and any double-byte spaces^* found are converted into single-byte spaces.
MVARCHAR	An error occurs.

^* 0xE38080 is treated as a double-byte space character code.