365 lines
8.6 KiB
C
365 lines
8.6 KiB
C
/* harfbuzz-buffer.c: Buffer of glyphs for substitution/positioning
|
|
*
|
|
* Copyright 2004,2007 Red Hat Software
|
|
*
|
|
* Portions Copyright 1996-2000 by
|
|
* David Turner, Robert Wilhelm, and Werner Lemberg.
|
|
*/
|
|
|
|
#include "harfbuzz-impl.h"
|
|
#include "harfbuzz-buffer-private.h"
|
|
#include "harfbuzz-gsub-private.h"
|
|
#include "harfbuzz-gpos-private.h"
|
|
|
|
/* Here is how the buffer works internally:
|
|
*
|
|
* There are two string pointers: in_string and out_string. They
|
|
* always have same allocated size, but different length and positions.
|
|
*
|
|
* As an optimization, both in_string and out_string may point to the
|
|
* same piece of memory, which is owned by in_string. This remains the
|
|
* case as long as:
|
|
*
|
|
* - copy_glyph() is called
|
|
* - replace_glyph() is called with inplace=TRUE
|
|
* - add_output_glyph() and add_output_glyphs() are not called
|
|
*
|
|
* In that case swap(), and copy_glyph(), and replace_glyph() are all
|
|
* mostly no-op.
|
|
*
|
|
* As soon an add_output_glyph[s]() or replace_glyph() with inplace=FALSE is
|
|
* called, out_string is moved over to an alternate buffer (alt_string), and
|
|
* its current contents (out_length entries) are copied to the alt buffer.
|
|
* This should all remain transparent to the user. swap() then switches
|
|
* in_string and alt_string. alt_string is not allocated until its needed,
|
|
* but after that it's grown with in_string unconditionally.
|
|
*
|
|
* The buffer->separate_out boolean keeps status of whether out_string points
|
|
* to in_string (FALSE) or alt_string (TRUE).
|
|
*/
|
|
|
|
/* Internal API */
|
|
|
|
static HB_Error
|
|
hb_buffer_ensure( HB_Buffer buffer,
|
|
HB_UInt size )
|
|
{
|
|
HB_UInt new_allocated = buffer->allocated;
|
|
|
|
if (size > new_allocated)
|
|
{
|
|
HB_Error error;
|
|
|
|
while (size > new_allocated)
|
|
new_allocated += (new_allocated >> 1) + 8;
|
|
|
|
if ( buffer->positions )
|
|
{
|
|
if ( REALLOC_ARRAY( buffer->positions, new_allocated, HB_PositionRec ) )
|
|
return error;
|
|
}
|
|
|
|
if ( REALLOC_ARRAY( buffer->in_string, new_allocated, HB_GlyphItemRec ) )
|
|
return error;
|
|
|
|
if ( buffer->separate_out )
|
|
{
|
|
if ( REALLOC_ARRAY( buffer->alt_string, new_allocated, HB_GlyphItemRec ) )
|
|
return error;
|
|
|
|
buffer->out_string = buffer->alt_string;
|
|
}
|
|
else
|
|
{
|
|
buffer->out_string = buffer->in_string;
|
|
|
|
if ( buffer->alt_string )
|
|
{
|
|
if ( REALLOC_ARRAY( buffer->alt_string, new_allocated, HB_GlyphItemRec ) )
|
|
return error;
|
|
}
|
|
}
|
|
|
|
buffer->allocated = new_allocated;
|
|
}
|
|
|
|
return HB_Err_Ok;
|
|
}
|
|
|
|
static HB_Error
|
|
hb_buffer_duplicate_out_buffer( HB_Buffer buffer )
|
|
{
|
|
if ( !buffer->alt_string )
|
|
{
|
|
HB_Error error;
|
|
|
|
if ( ALLOC_ARRAY( buffer->alt_string, buffer->allocated, HB_GlyphItemRec ) )
|
|
return error;
|
|
}
|
|
|
|
buffer->out_string = buffer->alt_string;
|
|
memcpy( buffer->out_string, buffer->in_string, buffer->out_length * sizeof (buffer->out_string[0]) );
|
|
buffer->separate_out = TRUE;
|
|
|
|
return HB_Err_Ok;
|
|
}
|
|
|
|
/* Public API */
|
|
|
|
HB_Error
|
|
hb_buffer_new( HB_Buffer *pbuffer )
|
|
{
|
|
HB_Buffer buffer;
|
|
HB_Error error;
|
|
|
|
if ( ALLOC( buffer, sizeof( HB_BufferRec ) ) )
|
|
return error;
|
|
|
|
buffer->allocated = 0;
|
|
buffer->in_string = NULL;
|
|
buffer->alt_string = NULL;
|
|
buffer->positions = NULL;
|
|
|
|
hb_buffer_clear( buffer );
|
|
|
|
*pbuffer = buffer;
|
|
|
|
return HB_Err_Ok;
|
|
}
|
|
|
|
void
|
|
hb_buffer_free( HB_Buffer buffer )
|
|
{
|
|
FREE( buffer->in_string );
|
|
FREE( buffer->alt_string );
|
|
buffer->out_string = NULL;
|
|
FREE( buffer->positions );
|
|
FREE( buffer );
|
|
}
|
|
|
|
void
|
|
hb_buffer_clear( HB_Buffer buffer )
|
|
{
|
|
buffer->in_length = 0;
|
|
buffer->out_length = 0;
|
|
buffer->in_pos = 0;
|
|
buffer->out_pos = 0;
|
|
buffer->out_string = buffer->in_string;
|
|
buffer->separate_out = FALSE;
|
|
buffer->max_ligID = 0;
|
|
}
|
|
|
|
HB_Error
|
|
hb_buffer_add_glyph( HB_Buffer buffer,
|
|
HB_UInt glyph_index,
|
|
HB_UInt properties,
|
|
HB_UInt cluster )
|
|
{
|
|
HB_Error error;
|
|
HB_GlyphItem glyph;
|
|
|
|
error = hb_buffer_ensure( buffer, buffer->in_length + 1 );
|
|
if ( error )
|
|
return error;
|
|
|
|
glyph = &buffer->in_string[buffer->in_length];
|
|
glyph->gindex = glyph_index;
|
|
glyph->properties = properties;
|
|
glyph->cluster = cluster;
|
|
glyph->component = 0;
|
|
glyph->ligID = 0;
|
|
glyph->gproperties = HB_GLYPH_PROPERTIES_UNKNOWN;
|
|
|
|
buffer->in_length++;
|
|
|
|
return HB_Err_Ok;
|
|
}
|
|
|
|
/* HarfBuzz-Internal API */
|
|
|
|
HB_INTERNAL void
|
|
_hb_buffer_clear_output( HB_Buffer buffer )
|
|
{
|
|
buffer->out_length = 0;
|
|
buffer->out_pos = 0;
|
|
buffer->out_string = buffer->in_string;
|
|
buffer->separate_out = FALSE;
|
|
}
|
|
|
|
HB_INTERNAL HB_Error
|
|
_hb_buffer_clear_positions( HB_Buffer buffer )
|
|
{
|
|
if ( !buffer->positions )
|
|
{
|
|
HB_Error error;
|
|
|
|
if ( ALLOC_ARRAY( buffer->positions, buffer->allocated, HB_PositionRec ) )
|
|
return error;
|
|
}
|
|
|
|
memset (buffer->positions, 0, sizeof (buffer->positions[0]) * buffer->in_length);
|
|
|
|
return HB_Err_Ok;
|
|
}
|
|
|
|
HB_INTERNAL void
|
|
_hb_buffer_swap( HB_Buffer buffer )
|
|
{
|
|
HB_GlyphItem tmp_string;
|
|
int tmp_length;
|
|
int tmp_pos;
|
|
|
|
if ( buffer->separate_out )
|
|
{
|
|
tmp_string = buffer->in_string;
|
|
buffer->in_string = buffer->out_string;
|
|
buffer->out_string = tmp_string;
|
|
buffer->alt_string = buffer->out_string;
|
|
}
|
|
|
|
tmp_length = buffer->in_length;
|
|
buffer->in_length = buffer->out_length;
|
|
buffer->out_length = tmp_length;
|
|
|
|
tmp_pos = buffer->in_pos;
|
|
buffer->in_pos = buffer->out_pos;
|
|
buffer->out_pos = tmp_pos;
|
|
}
|
|
|
|
/* The following function copies `num_out' elements from `glyph_data'
|
|
to `buffer->out_string', advancing the in array pointer in the structure
|
|
by `num_in' elements, and the out array pointer by `num_out' elements.
|
|
Finally, it sets the `length' field of `out' equal to
|
|
`pos' of the `out' structure.
|
|
|
|
If `component' is 0xFFFF, the component value from buffer->in_pos
|
|
will copied `num_out' times, otherwise `component' itself will
|
|
be used to fill the `component' fields.
|
|
|
|
If `ligID' is 0xFFFF, the ligID value from buffer->in_pos
|
|
will copied `num_out' times, otherwise `ligID' itself will
|
|
be used to fill the `ligID' fields.
|
|
|
|
The properties for all replacement glyphs are taken
|
|
from the glyph at position `buffer->in_pos'.
|
|
|
|
The cluster value for the glyph at position buffer->in_pos is used
|
|
for all replacement glyphs */
|
|
HB_INTERNAL HB_Error
|
|
_hb_buffer_add_output_glyphs( HB_Buffer buffer,
|
|
HB_UShort num_in,
|
|
HB_UShort num_out,
|
|
HB_UShort *glyph_data,
|
|
HB_UShort component,
|
|
HB_UShort ligID )
|
|
{
|
|
HB_Error error;
|
|
HB_UShort i;
|
|
HB_UInt properties;
|
|
HB_UInt cluster;
|
|
|
|
error = hb_buffer_ensure( buffer, buffer->out_pos + num_out );
|
|
if ( error )
|
|
return error;
|
|
|
|
if ( !buffer->separate_out )
|
|
{
|
|
error = hb_buffer_duplicate_out_buffer( buffer );
|
|
if ( error )
|
|
return error;
|
|
}
|
|
|
|
properties = buffer->in_string[buffer->in_pos].properties;
|
|
cluster = buffer->in_string[buffer->in_pos].cluster;
|
|
if ( component == 0xFFFF )
|
|
component = buffer->in_string[buffer->in_pos].component;
|
|
if ( ligID == 0xFFFF )
|
|
ligID = buffer->in_string[buffer->in_pos].ligID;
|
|
|
|
for ( i = 0; i < num_out; i++ )
|
|
{
|
|
HB_GlyphItem item = &buffer->out_string[buffer->out_pos + i];
|
|
|
|
item->gindex = glyph_data[i];
|
|
item->properties = properties;
|
|
item->cluster = cluster;
|
|
item->component = component;
|
|
item->ligID = ligID;
|
|
item->gproperties = HB_GLYPH_PROPERTIES_UNKNOWN;
|
|
}
|
|
|
|
buffer->in_pos += num_in;
|
|
buffer->out_pos += num_out;
|
|
|
|
buffer->out_length = buffer->out_pos;
|
|
|
|
return HB_Err_Ok;
|
|
}
|
|
|
|
HB_INTERNAL HB_Error
|
|
_hb_buffer_add_output_glyph( HB_Buffer buffer,
|
|
HB_UInt glyph_index,
|
|
HB_UShort component,
|
|
HB_UShort ligID )
|
|
{
|
|
HB_UShort glyph_data = glyph_index;
|
|
|
|
return _hb_buffer_add_output_glyphs ( buffer, 1, 1,
|
|
&glyph_data, component, ligID );
|
|
}
|
|
|
|
HB_INTERNAL HB_Error
|
|
_hb_buffer_copy_output_glyph ( HB_Buffer buffer )
|
|
{
|
|
HB_Error error;
|
|
|
|
error = hb_buffer_ensure( buffer, buffer->out_pos + 1 );
|
|
if ( error )
|
|
return error;
|
|
|
|
if ( buffer->separate_out )
|
|
{
|
|
buffer->out_string[buffer->out_pos] = buffer->in_string[buffer->in_pos];
|
|
}
|
|
|
|
buffer->in_pos++;
|
|
buffer->out_pos++;
|
|
buffer->out_length = buffer->out_pos;
|
|
|
|
return HB_Err_Ok;
|
|
}
|
|
|
|
HB_INTERNAL HB_Error
|
|
_hb_buffer_replace_output_glyph( HB_Buffer buffer,
|
|
HB_UInt glyph_index,
|
|
HB_Bool inplace )
|
|
{
|
|
|
|
HB_Error error;
|
|
|
|
if ( inplace )
|
|
{
|
|
error = _hb_buffer_copy_output_glyph ( buffer );
|
|
if ( error )
|
|
return error;
|
|
|
|
buffer->out_string[buffer->out_pos-1].gindex = glyph_index;
|
|
}
|
|
else
|
|
{
|
|
return _hb_buffer_add_output_glyph( buffer, glyph_index, 0xFFFF, 0xFFFF );
|
|
}
|
|
|
|
return HB_Err_Ok;
|
|
}
|
|
|
|
HB_INTERNAL HB_UShort
|
|
_hb_buffer_allocate_ligid( HB_Buffer buffer )
|
|
{
|
|
buffer->max_ligID++;
|
|
if (HB_UNLIKELY (buffer->max_ligID == 0))
|
|
buffer->max_ligID++;
|
|
|
|
return buffer->max_ligID;
|
|
}
|