OCI String Functions

This section describes the OCI string functions.

Table 18-17 String Functions

Function/Page	Purpose
OCIStringAllocSize()	Get allocated size of string memory in bytes
OCIStringAssign()	Assign string to string
OCIStringAssignText()	Assign text string to string
OCIStringPtr()	Get string pointer
OCIStringResize()	Resize string memory
OCIStringSize()	Get string size

OCIStringAllocSize()

Purpose

Gets allocated size of string memory in codepoints (Unicode) or in bytes.

Syntax

sword OCIStringAllocSize ( OCIEnv              *env,
                           OCIError            *err, 
                           CONST OCIString     *vs,
                           ub4                 *allocsize );

Parameters

env (IN/OUT): The OCI environment handle initialized in object mode.

See Also:
OCIEnvCreate() and OCIInitialize()
err (IN/OUT): The OCI error handle. If there is an error, it is recorded in err and this function returns OCI_ERROR. Obtain diagnostic information by calling OCIErrorGet().
vs (IN): String whose allocated size in bytes is returned. vs must be a non-NULL pointer.
allocsize (OUT): The allocated size of string memory in bytes is returned.

Comments

The allocated size is greater than or equal to the actual string size.

Related Functions

OCIErrorGet(), OCIStringResize(), OCIStringSize()

OCIStringAssign()

Purpose

Assigns one string to another string.

Syntax

sword OCIStringAssign ( OCIEnv               *env, 
                        OCIError             *err, 
                        CONST OCIString      *rhs, 
                        OCIString            **lhs );

Parameters

env (IN/OUT): The OCI environment handle initialized in object mode.

See Also:
OCIEnvCreate() and OCIInitialize()
err (IN/OUT): The OCI error handle. If there is an error, it is recorded in err and this function returns OCI_ERROR. Obtain diagnostic information by calling OCIErrorGet().
rhs (IN): Right-hand side (source) of the assignment. Can be in UTF-16.
lhs (IN/OUT): Left-hand side (target) of the assignment. Its buffer is UTF-16 if rhs is UTF-16.

Comments

Assigns rhs string to lhs string. The lhs string may be resized depending upon the size of the rhs. The assigned string is NULL-terminated. The length field will not include the extra codepoint or byte needed for NULL-termination.

This function returns an error if the assignment operation runs out of space.

Related Functions

OCIErrorGet(), OCIStringAssignText()

OCIStringAssignText()

Purpose

Assigns the source text string to the target string.

Syntax

sword OCIStringAssignText ( OCIEnv           *env,
                            OCIError         *err, 
                            CONST OraText    *rhs, 
                            ub2              rhs_len,
                            OCIString        **lhs );

Parameters

env (IN/OUT): The OCI environment handle initialized in object mode.

See Also:
OCIEnvCreate() and OCIInitialize()
err (IN/OUT): The OCI error handle. If there is an error, it is recorded in err and this function returns OCI_ERROR. Obtain diagnostic information by calling OCIErrorGet().
rhs (IN): Right-hand side (source) of the assignment, a text or UTF-16 Unicode string.
rhs_len (IN): Length of the rhs string in bytes.
lhs (IN/OUT): Left-hand side (target) of the assignment. Its buffer is Unicode if rhs is Unicode.

Comments

Related Functions

OCIErrorGet(), OCIStringAssign()

OCIStringPtr()

Purpose

Gets a pointer to the text of a given string.

Syntax

text *OCIStringPtr ( OCIEnv               *env,
                     CONST OCIString      *vs );

Parameters

env (IN/OUT): The OCI environment handle initialized in object mode.

See Also:
OCIEnvCreate() and OCIInitialize()
vs (IN): Pointer to the OCIString object whose character string will be returned. If vs is in UTF-16, the returned buffer will also be UTF-16. If you want to know the encoding of the returned buffer, check the UTF-16 information in the OCIString vs itself, since it is not guaranteed that a particular OCIString must have the same setting as env does. The function to check should be some object OCI function designed to check member fields in objects.

Comments

None.

Related Functions

OCIErrorGet(), OCIStringAssign()

OCIStringResize()

Purpose

Resizes the memory of a given string.

Syntax

sword OCIStringResize ( OCIEnv          *env,
                        OCIError        *err,
                        ub4             new_size,
                        OCIString       **str );

Parameters

env (IN/OUT): The OCI environment handle initialized in object mode.

See Also:
OCIEnvCreate() and OCIInitialize()
err (IN/OUT): The OCI error handle. If there is an error, it is recorded in err and this function returns OCI_ERROR. Obtain diagnostic information by calling OCIErrorGet().
new_size (IN): New memory size of the string in bytes. new_size must include space for the NULL character as the string terminator.
str (IN/OUT): Allocated memory for the string which is freed from the OCI object cache.

Comments

This function resizes the memory of the given variable-length string in the object cache. Contents of the string are not preserved. This function may allocate the string in a new memory region, in which case the original memory occupied by the given string is freed. If str is NULL, this function allocates memory for the string. If new_size is 0, this function frees the memory occupied by str and a NULL pointer value is returned.

Related Functions

OCIErrorGet(), OCIStringAllocSize(), OCIStringSize()

OCIStringSize()

Purpose

Gets the size of the given string vs.

Syntax

ub4 OCIStringSize ( OCIEnv              *env,
                    CONST OCIString     *vs );

Parameters

env (IN/OUT): The OCI environment handle initialized in object mode.

See Also:
OCIEnvCreate() and OCIInitialize()
vs (IN): String whose size is returned, in number of bytes.

Comments

The returned size does not include an extra byte for NULL termination.

Related Functions

OCIErrorGet(), OCIStringResize()