Edits the shape of the context text.
Layout library (libi18n.a)
#include <sys/lc_layout.h>
int layout_editshape ( layout_object, EditType, index, InpBuf, Inpsize, OutBuf, OutSize)
LayoutObject layout_object;
BooleanValue EditType;
size_t *index;
const char *InpBuf;
size_t *Inpsize;
void *OutBuf;
size_t *OutSize;
int wcslayout_object_editshape(layout_object, EditType, index, InpBuf, Inpsize, OutBuf, OutSize)
LayoutObject layout_object;
BooleanValue EditType;
size_t *index;
const wchar t *InpBuf;
size_t *InpSize;
void *OutBuf;
size_t *OutSize;The layout_object_editshape and wcslayout_object_editshape subroutines provide the shapes of the context text. The shapes are defined by the code element specified by the index parameter and any surrounding code elements specified by the ShapeContextSize layout value of the LayoutObject structure. The layout_object parameter specifies this LayoutObject structure.
Use the layout_object_editshape subroutine when editing code elements of one byte. Use the wcslayout_object_editshape subroutine when editing single code elements of multibytes. These subroutines do not affect any state maintained by the layout_object_transform or wcslayout_object_transform subroutine.
| Item | Description |
|---|---|
| layout_object | Specifies the LayoutObject structure created by the layout_object_create subroutine. |
| EditType | Specifies the type of edit shaping. When the EditType parameter
stipulates the EditInput field, the subroutine reads the
current code element defined by the index parameter and any
preceding code elements defined by ShapeContextSize layout value of
the LayoutObject structure. When the EditType parameter
stipulates the EditReplace field, the subroutine reads the
current code element defined by the index parameter and any
surrounding code elements defined by ShapeContextSize layout value
of the LayoutObject structure. Note: The editing direction
defined by the Orientation and TEXT_VISUAL of the TypeOfText layout
values of the LayoutObject structure determines which code
elements are preceding and succeeding.
When the ActiveShapeEditing layout value of the LayoutObject structure is set to True, the LayoutObject structure maintains the state of the EditInput field that may affect subsequent calls to these subroutines with the EditInput field defined by the EditType parameter. The state of the EditInput field of LayoutObject structure is not affected when the EditType parameter is set to the EditReplace field. To reset the state of the EditInput field to its initial state, call these subroutines with the InpBuf parameter set to NULL. The state of the EditInput field is not affected if errors occur within the subroutines. |
| index | Specifies an offset (in bytes) to the start of a code element
in the InpBuf parameter on input. The InpBuf parameter
provides the base text to be edited. In addition, the context of the
surrounding code elements is considered where the minimum set of code
elements needed for the specific context dependent script(s) is identified
by the ShapeContextSize layout value. If the set of surrounding code elements defined by the index, InpBuf, and InpSize parameters is less than the size of front and back of the ShapeContextSize layout value, these subroutines assume there is no additional context available. The caller must provide the minimum context if it is available. The index parameter is in units associated with the type of the InpBuf parameter. On return, the index parameter is modified to indicate the offset to the first code element of the InpBuf parameter that required shaping. The number of code elements that required shaping is indicated on return by the InpSize parameter. |
| InpBuf | Specifies the source to be processed. A Null value with the EditInput field
in the EditType parameter indicates a request to reset the
state of the EditInput field to its initial state. Any portion of the InpBuf parameter indicates the necessity for redrawing or shaping. |
| InpSize | Specifies the number of code elements to be processed in
units on input. These units are associated with the types for these
subroutines. A value of -1 indicates that the input is delimited by
a Null code element. On return, the value is modified to the actual number of code elements needed by the InpBuf parameter. A value of 0 when the value of the EditType parameter is the EditInput field indicates that the state of the EditInput field is reset to its initial state. If the OutBuf parameter is not NULL, the respective shaped code elements are written into the OutBuf parameter. |
| OutBuf | Contains the shaped output text. You can specify this parameter
as a Null pointer to indicate that no transformed text is required.
If Null, the subroutines return the index and InpSize parameters,
which specify the amount of text required, to be redrawn. The encoding of the OutBuf parameter depends on the ShapeCharset layout value defined in layout_object parameter. If the ActiveShapeEditing layout value is set to False, the encoding of the OutBuf parameter is to be the same as the code set of the locale associated with the specified LayoutObject structure. |
| OutSize | Specifies the size of the output buffer on input in number
of bytes. Only the code elements required to be shaped are written
into the OutBuf parameter. The output buffer should be large enough to contain the shaped result; otherwise, only partial shaping is performed. If the ActiveShapeEditing layout value is set to True, the OutBuf parameter should be allocated to contain at least the number of code elements in the InpBuf parameter multiplied by the value of the ShapeCharsetSize layout value. On return, the OutSize parameter is modified to the actual number of bytes placed in the output buffer. When the OutSize parameter is specified as 0, the subroutines calculate the size of an output buffer large enough to contain the transformed text from the input buffer. The result will be returned in this field. The content of the buffers specifies by the InpBuf and OutBuf parameters, and the value of the InpSize parameter, remain unchanged. |
Upon successful completion, these subroutines return a value of 0. The index and InpSize parameters return the minimum set of code elements required to be redrawn.
If these subroutines fail, they return the following error codes:
| Item | Description |
|---|---|
| LAYOUT_EILSEQ | Shaping stopped due to an input code element that cannot be shaped. The index parameter indicates the code element that caused the error. This code element is either a valid code element that cannot be shaped according to the ShapeCharset layout value or an invalid code element not defined by the code set defined in the LayoutObject structure. Use the mbtowc or wctomb subroutine in the same locale as the LayoutObject structure to determine if the code element is valid. |
| LAYOUT_E2BIG | The output buffer is too small and the source text was not processed. The index and InpSize parameters are not guaranteed on return. |
| LAYOUT_EINVAL | Shaping stopped due to an incomplete code element or shift
sequence at the end of input buffer. The InpSize parameter
indicates the number of code elements successfully transformed. Note: You
can use this error code to determine the code element causing the
error.
|
| LAYOUT_ERANGE | Either the index parameter is outside the range as defined by the InpSize parameter, more than 15 embedding levels are in the source text, or the InpBuf parameter contains unbalanced Directional Format (Push/Pop). |