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harfbuzz/src/hb-buffer.cc

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/*
* Copyright © 1998-2004 David Turner and Werner Lemberg
* Copyright © 2004,2007,2009,2010 Red Hat, Inc.
* Copyright © 2011,2012 Google, Inc.
*
* This is part of HarfBuzz, a text shaping library.
*
* Permission is hereby granted, without written agreement and without
* license or royalty fees, to use, copy, modify, and distribute this
* software and its documentation for any purpose, provided that the
* above copyright notice and the following two paragraphs appear in
* all copies of this software.
*
* IN NO EVENT SHALL THE COPYRIGHT HOLDER BE LIABLE TO ANY PARTY FOR
* DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
* ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN
* IF THE COPYRIGHT HOLDER HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
* DAMAGE.
*
* THE COPYRIGHT HOLDER SPECIFICALLY DISCLAIMS ANY WARRANTIES, INCLUDING,
* BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE PROVIDED HEREUNDER IS
* ON AN "AS IS" BASIS, AND THE COPYRIGHT HOLDER HAS NO OBLIGATION TO
* PROVIDE MAINTENANCE, SUPPORT, UPDATES, ENHANCEMENTS, OR MODIFICATIONS.
*
* Red Hat Author(s): Owen Taylor, Behdad Esfahbod
* Google Author(s): Behdad Esfahbod
*/
#include "hb-buffer.hh"
#include "hb-utf.hh"
/**
* SECTION: hb-buffer
* @title: hb-buffer
* @short_description: Input and output buffers
* @include: hb.h
*
* Buffers serve a dual role in HarfBuzz; before shaping, they hold
* the input characters that are passed to hb_shape(), and after
* shaping they hold the output glyphs.
**/
/**
* hb_segment_properties_equal:
* @a: first #hb_segment_properties_t to compare.
* @b: second #hb_segment_properties_t to compare.
*
* Checks the equality of two #hb_segment_properties_t's.
*
* Return value:
* %true if all properties of @a equal those of @b, %false otherwise.
*
* Since: 0.9.7
**/
hb_bool_t
hb_segment_properties_equal (const hb_segment_properties_t *a,
const hb_segment_properties_t *b)
{
return a->direction == b->direction &&
a->script == b->script &&
a->language == b->language &&
a->reserved1 == b->reserved1 &&
a->reserved2 == b->reserved2;
}
/**
* hb_segment_properties_hash:
* @p: #hb_segment_properties_t to hash.
*
* Creates a hash representing @p.
*
* Return value:
* A hash of @p.
*
* Since: 0.9.7
**/
unsigned int
hb_segment_properties_hash (const hb_segment_properties_t *p)
{
return ((unsigned int) p->direction * 31 +
(unsigned int) p->script) * 31 +
(intptr_t) (p->language);
}
/**
* hb_segment_properties_overlay:
* @p: #hb_segment_properties_t to fill in.
* @src: #hb_segment_properties_t to fill in from.
*
* Fills in missing fields of @p from @src in a considered manner.
*
* First, if @p does not have direction set, direction is copied from @src.
*
* Next, if @p and @src have the same direction (which can be unset), if @p
* does not have script set, script is copied from @src.
*
* Finally, if @p and @src have the same direction and script (which either
* can be unset), if @p does not have language set, language is copied from
* @src.
*
* Since: 3.3.0
**/
void
hb_segment_properties_overlay (hb_segment_properties_t *p,
const hb_segment_properties_t *src)
{
if (unlikely (!p || !src))
return;
if (!p->direction)
p->direction = src->direction;
if (p->direction != src->direction)
return;
if (!p->script)
p->script = src->script;
if (p->script != src->script)
return;
if (!p->language)
p->language = src->language;
}
/* Here is how the buffer works internally:
*
* There are two info pointers: info and out_info. They always have
* the same allocated size, but different lengths.
*
* As an optimization, both info and out_info may point to the
* same piece of memory, which is owned by info. This remains the
* case as long as out_len doesn't exceed i at any time.
* In that case, sync() is mostly no-op and the glyph operations
* operate mostly in-place.
*
* As soon as out_info gets longer than info, out_info is moved over
* to an alternate buffer (which we reuse the pos buffer for), and its
* current contents (out_len entries) are copied to the new place.
*
* This should all remain transparent to the user. sync() then
* switches info over to out_info and does housekeeping.
*/
/* Internal API */
bool
hb_buffer_t::enlarge (unsigned int size)
{
if (unlikely (!successful))
return false;
if (unlikely (size > max_len))
{
successful = false;
return false;
}
unsigned int new_allocated = allocated;
hb_glyph_position_t *new_pos = nullptr;
hb_glyph_info_t *new_info = nullptr;
bool separate_out = out_info != info;
if (unlikely (hb_unsigned_mul_overflows (size, sizeof (info[0]))))
goto done;
while (size >= new_allocated)
new_allocated += (new_allocated >> 1) + 32;
static_assert ((sizeof (info[0]) == sizeof (pos[0])), "");
if (unlikely (hb_unsigned_mul_overflows (new_allocated, sizeof (info[0]))))
goto done;
new_pos = (hb_glyph_position_t *) hb_realloc (pos, new_allocated * sizeof (pos[0]));
new_info = (hb_glyph_info_t *) hb_realloc (info, new_allocated * sizeof (info[0]));
done:
if (unlikely (!new_pos || !new_info))
successful = false;
if (likely (new_pos))
pos = new_pos;
if (likely (new_info))
info = new_info;
out_info = separate_out ? (hb_glyph_info_t *) pos : info;
if (likely (successful))
allocated = new_allocated;
return likely (successful);
}
bool
hb_buffer_t::make_room_for (unsigned int num_in,
unsigned int num_out)
{
if (unlikely (!ensure (out_len + num_out))) return false;
if (out_info == info &&
out_len + num_out > idx + num_in)
{
assert (have_output);
out_info = (hb_glyph_info_t *) pos;
memcpy (out_info, info, out_len * sizeof (out_info[0]));
}
return true;
}
bool
hb_buffer_t::shift_forward (unsigned int count)
{
assert (have_output);
if (unlikely (!ensure (len + count))) return false;
memmove (info + idx + count, info + idx, (len - idx) * sizeof (info[0]));
if (idx + count > len)
{
/* Under memory failure we might expose this area. At least
* clean it up. Oh well...
*
* Ideally, we should at least set Default_Ignorable bits on
* these, as well as consistent cluster values. But the former
* is layering violation... */
memset (info + len, 0, (idx + count - len) * sizeof (info[0]));
}
len += count;
idx += count;
return true;
}
hb_buffer_t::scratch_buffer_t *
hb_buffer_t::get_scratch_buffer (unsigned int *size)
{
have_output = false;
have_positions = false;
out_len = 0;
out_info = info;
assert ((uintptr_t) pos % sizeof (scratch_buffer_t) == 0);
*size = allocated * sizeof (pos[0]) / sizeof (scratch_buffer_t);
return (scratch_buffer_t *) (void *) pos;
}
/* HarfBuzz-Internal API */
void
hb_buffer_t::similar (const hb_buffer_t &src)
{
hb_unicode_funcs_destroy (unicode);
unicode = hb_unicode_funcs_reference (src.unicode);
flags = src.flags;
cluster_level = src.cluster_level;
replacement = src.invisible;
invisible = src.invisible;
not_found = src.not_found;
}
void
hb_buffer_t::reset ()
{
hb_unicode_funcs_destroy (unicode);
unicode = hb_unicode_funcs_reference (hb_unicode_funcs_get_default ());
flags = HB_BUFFER_FLAG_DEFAULT;
cluster_level = HB_BUFFER_CLUSTER_LEVEL_DEFAULT;
replacement = HB_BUFFER_REPLACEMENT_CODEPOINT_DEFAULT;
invisible = 0;
not_found = 0;
clear ();
}
void
hb_buffer_t::clear ()
{
content_type = HB_BUFFER_CONTENT_TYPE_INVALID;
hb_segment_properties_t default_props = HB_SEGMENT_PROPERTIES_DEFAULT;
props = default_props;
successful = true;
shaping_failed = false;
have_output = false;
have_positions = false;
idx = 0;
len = 0;
out_len = 0;
out_info = info;
memset (context, 0, sizeof context);
memset (context_len, 0, sizeof context_len);
deallocate_var_all ();
serial = 0;
scratch_flags = HB_BUFFER_SCRATCH_FLAG_DEFAULT;
}
void
hb_buffer_t::enter ()
{
deallocate_var_all ();
serial = 0;
shaping_failed = false;
scratch_flags = HB_BUFFER_SCRATCH_FLAG_DEFAULT;
if (likely (!hb_unsigned_mul_overflows (len, HB_BUFFER_MAX_LEN_FACTOR)))
{
max_len = hb_max (len * HB_BUFFER_MAX_LEN_FACTOR,
(unsigned) HB_BUFFER_MAX_LEN_MIN);
}
if (likely (!hb_unsigned_mul_overflows (len, HB_BUFFER_MAX_OPS_FACTOR)))
{
max_ops = hb_max (len * HB_BUFFER_MAX_OPS_FACTOR,
(unsigned) HB_BUFFER_MAX_OPS_MIN);
}
}
void
hb_buffer_t::leave ()
{
max_len = HB_BUFFER_MAX_LEN_DEFAULT;
max_ops = HB_BUFFER_MAX_OPS_DEFAULT;
deallocate_var_all ();
serial = 0;
// Intentionally not reseting shaping_failed, such that it can be inspected.
}
void
hb_buffer_t::add (hb_codepoint_t codepoint,
unsigned int cluster)
{
hb_glyph_info_t *glyph;
if (unlikely (!ensure (len + 1))) return;
glyph = &info[len];
memset (glyph, 0, sizeof (*glyph));
glyph->codepoint = codepoint;
glyph->mask = 0;
glyph->cluster = cluster;
len++;
}
void
hb_buffer_t::add_info (const hb_glyph_info_t &glyph_info)
{
if (unlikely (!ensure (len + 1))) return;
info[len] = glyph_info;
len++;
}
void
hb_buffer_t::clear_output ()
{
have_output = true;
have_positions = false;
idx = 0;
out_len = 0;
out_info = info;
}
void
hb_buffer_t::clear_positions ()
{
have_output = false;
have_positions = true;
out_len = 0;
out_info = info;
hb_memset (pos, 0, sizeof (pos[0]) * len);
}
void
hb_buffer_t::sync ()
{
assert (have_output);
assert (idx <= len);
if (unlikely (!successful || !next_glyphs (len - idx)))
goto reset;
if (out_info != info)
{
pos = (hb_glyph_position_t *) info;
info = out_info;
}
len = out_len;
reset:
have_output = false;
out_len = 0;
out_info = info;
idx = 0;
}
bool
hb_buffer_t::move_to (unsigned int i)
{
if (!have_output)
{
assert (i <= len);
idx = i;
return true;
}
if (unlikely (!successful))
return false;
assert (i <= out_len + (len - idx));
if (out_len < i)
{
unsigned int count = i - out_len;
if (unlikely (!make_room_for (count, count))) return false;
memmove (out_info + out_len, info + idx, count * sizeof (out_info[0]));
idx += count;
out_len += count;
}
else if (out_len > i)
{
/* Tricky part: rewinding... */
unsigned int count = out_len - i;
/* This will blow in our face if memory allocation fails later
* in this same lookup...
*
* We used to shift with extra 32 items.
* But that would leave empty slots in the buffer in case of allocation
* failures. See comments in shift_forward(). This can cause O(N^2)
* behavior more severely than adding 32 empty slots can... */
if (unlikely (idx < count && !shift_forward (count - idx))) return false;
assert (idx >= count);
idx -= count;
out_len -= count;
memmove (info + idx, out_info + out_len, count * sizeof (out_info[0]));
}
return true;
}
void
hb_buffer_t::set_masks (hb_mask_t value,
hb_mask_t mask,
unsigned int cluster_start,
unsigned int cluster_end)
{
hb_mask_t not_mask = ~mask;
value &= mask;
if (!mask)
return;
unsigned int count = len;
for (unsigned int i = 0; i < count; i++)
if (cluster_start <= info[i].cluster && info[i].cluster < cluster_end)
info[i].mask = (info[i].mask & not_mask) | value;
}
void
hb_buffer_t::merge_clusters_impl (unsigned int start,
unsigned int end)
{
if (cluster_level == HB_BUFFER_CLUSTER_LEVEL_CHARACTERS)
{
unsafe_to_break (start, end);
return;
}
unsigned int cluster = info[start].cluster;
for (unsigned int i = start + 1; i < end; i++)
cluster = hb_min (cluster, info[i].cluster);
/* Extend end */
while (end < len && info[end - 1].cluster == info[end].cluster)
end++;
/* Extend start */
while (idx < start && info[start - 1].cluster == info[start].cluster)
start--;
/* If we hit the start of buffer, continue in out-buffer. */
if (idx == start)
for (unsigned int i = out_len; i && out_info[i - 1].cluster == info[start].cluster; i--)
set_cluster (out_info[i - 1], cluster);
for (unsigned int i = start; i < end; i++)
set_cluster (info[i], cluster);
}
void
hb_buffer_t::merge_out_clusters (unsigned int start,
unsigned int end)
{
if (cluster_level == HB_BUFFER_CLUSTER_LEVEL_CHARACTERS)
return;
if (unlikely (end - start < 2))
return;
unsigned int cluster = out_info[start].cluster;
for (unsigned int i = start + 1; i < end; i++)
cluster = hb_min (cluster, out_info[i].cluster);
/* Extend start */
while (start && out_info[start - 1].cluster == out_info[start].cluster)
start--;
/* Extend end */
while (end < out_len && out_info[end - 1].cluster == out_info[end].cluster)
end++;
/* If we hit the end of out-buffer, continue in buffer. */
if (end == out_len)
for (unsigned int i = idx; i < len && info[i].cluster == out_info[end - 1].cluster; i++)
set_cluster (info[i], cluster);
for (unsigned int i = start; i < end; i++)
set_cluster (out_info[i], cluster);
}
void
hb_buffer_t::delete_glyph ()
{
/* The logic here is duplicated in hb_ot_hide_default_ignorables(). */
unsigned int cluster = info[idx].cluster;
if ((idx + 1 < len && cluster == info[idx + 1].cluster) ||
(out_len && cluster == out_info[out_len - 1].cluster))
{
/* Cluster survives; do nothing. */
goto done;
}
/* TODO We need to just merge one direction, with whichever is smaller. */
if (out_len)
{
/* Merge cluster backward. */
if (cluster < out_info[out_len - 1].cluster)
{
unsigned int mask = info[idx].mask;
unsigned int old_cluster = out_info[out_len - 1].cluster;
for (unsigned i = out_len; i && out_info[i - 1].cluster == old_cluster; i--)
set_cluster (out_info[i - 1], cluster, mask);
}
goto done;
}
if (idx + 1 < len)
{
/* Merge cluster forward. */
merge_clusters (idx, idx + 2);
goto done;
}
done:
skip_glyph ();
}
void
hb_buffer_t::guess_segment_properties ()
{
assert_unicode ();
/* If script is set to INVALID, guess from buffer contents */
if (props.script == HB_SCRIPT_INVALID) {
for (unsigned int i = 0; i < len; i++) {
hb_script_t script = unicode->script (info[i].codepoint);
if (likely (script != HB_SCRIPT_COMMON &&
script != HB_SCRIPT_INHERITED &&
script != HB_SCRIPT_UNKNOWN)) {
props.script = script;
break;
}
}
}
/* If direction is set to INVALID, guess from script */
if (props.direction == HB_DIRECTION_INVALID) {
props.direction = hb_script_get_horizontal_direction (props.script);
if (props.direction == HB_DIRECTION_INVALID)
props.direction = HB_DIRECTION_LTR;
}
/* If language is not set, use default language from locale */
if (props.language == HB_LANGUAGE_INVALID) {
/* TODO get_default_for_script? using $LANGUAGE */
props.language = hb_language_get_default ();
}
}
/* Public API */
DEFINE_NULL_INSTANCE (hb_buffer_t) =
{
HB_OBJECT_HEADER_STATIC,
const_cast<hb_unicode_funcs_t *> (&_hb_Null_hb_unicode_funcs_t),
HB_BUFFER_FLAG_DEFAULT,
HB_BUFFER_CLUSTER_LEVEL_DEFAULT,
HB_BUFFER_REPLACEMENT_CODEPOINT_DEFAULT,
0, /* invisible */
0, /* not_found */
HB_BUFFER_CONTENT_TYPE_INVALID,
HB_SEGMENT_PROPERTIES_DEFAULT,
false, /* successful */
true, /* shaping_failed */
false, /* have_output */
true /* have_positions */
/* Zero is good enough for everything else. */
};
/**
* hb_buffer_create:
*
* Creates a new #hb_buffer_t with all properties to defaults.
*
* Return value: (transfer full):
* A newly allocated #hb_buffer_t with a reference count of 1. The initial
* reference count should be released with hb_buffer_destroy() when you are done
* using the #hb_buffer_t. This function never returns %NULL. If memory cannot
* be allocated, a special #hb_buffer_t object will be returned on which
* hb_buffer_allocation_successful() returns %false.
*
* Since: 0.9.2
**/
hb_buffer_t *
hb_buffer_create ()
{
hb_buffer_t *buffer;
if (!(buffer = hb_object_create<hb_buffer_t> ()))
return hb_buffer_get_empty ();
buffer->max_len = HB_BUFFER_MAX_LEN_DEFAULT;
buffer->max_ops = HB_BUFFER_MAX_OPS_DEFAULT;
buffer->reset ();
return buffer;
}
/**
* hb_buffer_create_similar:
* @src: An #hb_buffer_t
*
* Creates a new #hb_buffer_t, similar to hb_buffer_create(). The only
* difference is that the buffer is configured similarly to @src.
*
* Return value: (transfer full):
* A newly allocated #hb_buffer_t, similar to hb_buffer_create().
*
* Since: 3.3.0
**/
hb_buffer_t *
hb_buffer_create_similar (const hb_buffer_t *src)
{
hb_buffer_t *buffer = hb_buffer_create ();
buffer->similar (*src);
return buffer;
}
/**
* hb_buffer_reset:
* @buffer: An #hb_buffer_t
*
* Resets the buffer to its initial status, as if it was just newly created
* with hb_buffer_create().
*
* Since: 0.9.2
**/
void
hb_buffer_reset (hb_buffer_t *buffer)
{
if (unlikely (hb_object_is_immutable (buffer)))
return;
buffer->reset ();
}
/**
* hb_buffer_get_empty:
*
* Fetches an empty #hb_buffer_t.
*
* Return value: (transfer full): The empty buffer
*
* Since: 0.9.2
**/
hb_buffer_t *
hb_buffer_get_empty ()
{
return const_cast<hb_buffer_t *> (&Null (hb_buffer_t));
}
/**
* hb_buffer_reference: (skip)
* @buffer: An #hb_buffer_t
*
* Increases the reference count on @buffer by one. This prevents @buffer from
* being destroyed until a matching call to hb_buffer_destroy() is made.
*
* Return value: (transfer full):
* The referenced #hb_buffer_t.
*
* Since: 0.9.2
**/
hb_buffer_t *
hb_buffer_reference (hb_buffer_t *buffer)
{
return hb_object_reference (buffer);
}
/**
* hb_buffer_destroy: (skip)
* @buffer: An #hb_buffer_t
*
* Deallocate the @buffer.
* Decreases the reference count on @buffer by one. If the result is zero, then
* @buffer and all associated resources are freed. See hb_buffer_reference().
*
* Since: 0.9.2
**/
void
hb_buffer_destroy (hb_buffer_t *buffer)
{
if (!hb_object_destroy (buffer)) return;
hb_unicode_funcs_destroy (buffer->unicode);
hb_free (buffer->info);
hb_free (buffer->pos);
#ifndef HB_NO_BUFFER_MESSAGE
if (buffer->message_destroy)
buffer->message_destroy (buffer->message_data);
#endif
hb_free (buffer);
}
/**
* hb_buffer_set_user_data: (skip)
* @buffer: An #hb_buffer_t
* @key: The user-data key
* @data: A pointer to the user data
* @destroy: (nullable): A callback to call when @data is not needed anymore
* @replace: Whether to replace an existing data with the same key
*
* Attaches a user-data key/data pair to the specified buffer.
*
* Return value: %true if success, %false otherwise
*
* Since: 0.9.2
**/
hb_bool_t
hb_buffer_set_user_data (hb_buffer_t *buffer,
hb_user_data_key_t *key,
void * data,
hb_destroy_func_t destroy,
hb_bool_t replace)
{
return hb_object_set_user_data (buffer, key, data, destroy, replace);
}
/**
* hb_buffer_get_user_data: (skip)
* @buffer: An #hb_buffer_t
* @key: The user-data key to query
*
* Fetches the user data associated with the specified key,
* attached to the specified buffer.
*
* Return value: (transfer none): A pointer to the user data
*
* Since: 0.9.2
**/
void *
hb_buffer_get_user_data (hb_buffer_t *buffer,
hb_user_data_key_t *key)
{
return hb_object_get_user_data (buffer, key);
}
/**
* hb_buffer_set_content_type:
* @buffer: An #hb_buffer_t
* @content_type: The type of buffer contents to set
*
* Sets the type of @buffer contents. Buffers are either empty, contain
* characters (before shaping), or contain glyphs (the result of shaping).
*
* Since: 0.9.5
**/
void
hb_buffer_set_content_type (hb_buffer_t *buffer,
hb_buffer_content_type_t content_type)
{
buffer->content_type = content_type;
}
/**
* hb_buffer_get_content_type:
* @buffer: An #hb_buffer_t
*
* Fetches the type of @buffer contents. Buffers are either empty, contain
* characters (before shaping), or contain glyphs (the result of shaping).
*
* Return value:
* The type of @buffer contents
*
* Since: 0.9.5
**/
hb_buffer_content_type_t
hb_buffer_get_content_type (const hb_buffer_t *buffer)
{
return buffer->content_type;
}
/**
* hb_buffer_set_unicode_funcs:
* @buffer: An #hb_buffer_t
* @unicode_funcs: The Unicode-functions structure
*
* Sets the Unicode-functions structure of a buffer to
* @unicode_funcs.
*
* Since: 0.9.2
**/
void
hb_buffer_set_unicode_funcs (hb_buffer_t *buffer,
hb_unicode_funcs_t *unicode_funcs)
{
if (unlikely (hb_object_is_immutable (buffer)))
return;
if (!unicode_funcs)
unicode_funcs = hb_unicode_funcs_get_default ();
hb_unicode_funcs_reference (unicode_funcs);
hb_unicode_funcs_destroy (buffer->unicode);
buffer->unicode = unicode_funcs;
}
/**
* hb_buffer_get_unicode_funcs:
* @buffer: An #hb_buffer_t
*
* Fetches the Unicode-functions structure of a buffer.
*
* Return value: The Unicode-functions structure
*
* Since: 0.9.2
**/
hb_unicode_funcs_t *
hb_buffer_get_unicode_funcs (const hb_buffer_t *buffer)
{
return buffer->unicode;
}
/**
* hb_buffer_set_direction:
* @buffer: An #hb_buffer_t
* @direction: the #hb_direction_t of the @buffer
*
* Set the text flow direction of the buffer. No shaping can happen without
* setting @buffer direction, and it controls the visual direction for the
* output glyphs; for RTL direction the glyphs will be reversed. Many layout
* features depend on the proper setting of the direction, for example,
* reversing RTL text before shaping, then shaping with LTR direction is not
* the same as keeping the text in logical order and shaping with RTL
* direction.
*
* Since: 0.9.2
**/
void
hb_buffer_set_direction (hb_buffer_t *buffer,
hb_direction_t direction)
{
if (unlikely (hb_object_is_immutable (buffer)))
return;
buffer->props.direction = direction;
}
/**
* hb_buffer_get_direction:
* @buffer: An #hb_buffer_t
*
* See hb_buffer_set_direction()
*
* Return value:
* The direction of the @buffer.
*
* Since: 0.9.2
**/
hb_direction_t
hb_buffer_get_direction (const hb_buffer_t *buffer)
{
return buffer->props.direction;
}
/**
* hb_buffer_set_script:
* @buffer: An #hb_buffer_t
* @script: An #hb_script_t to set.
*
* Sets the script of @buffer to @script.
*
* Script is crucial for choosing the proper shaping behaviour for scripts that
* require it (e.g. Arabic) and the which OpenType features defined in the font
* to be applied.
*
* You can pass one of the predefined #hb_script_t values, or use
* hb_script_from_string() or hb_script_from_iso15924_tag() to get the
* corresponding script from an ISO 15924 script tag.
*
* Since: 0.9.2
**/
void
hb_buffer_set_script (hb_buffer_t *buffer,
hb_script_t script)
{
if (unlikely (hb_object_is_immutable (buffer)))
return;
buffer->props.script = script;
}
/**
* hb_buffer_get_script:
* @buffer: An #hb_buffer_t
*
* Fetches the script of @buffer.
*
* Return value:
* The #hb_script_t of the @buffer
*
* Since: 0.9.2
**/
hb_script_t
hb_buffer_get_script (const hb_buffer_t *buffer)
{
return buffer->props.script;
}
/**
* hb_buffer_set_language:
* @buffer: An #hb_buffer_t
* @language: An hb_language_t to set
*
* Sets the language of @buffer to @language.
*
* Languages are crucial for selecting which OpenType feature to apply to the
* buffer which can result in applying language-specific behaviour. Languages
* are orthogonal to the scripts, and though they are related, they are
* different concepts and should not be confused with each other.
*
* Use hb_language_from_string() to convert from BCP 47 language tags to
* #hb_language_t.
*
* Since: 0.9.2
**/
void
hb_buffer_set_language (hb_buffer_t *buffer,
hb_language_t language)
{
if (unlikely (hb_object_is_immutable (buffer)))
return;
buffer->props.language = language;
}
/**
* hb_buffer_get_language:
* @buffer: An #hb_buffer_t
*
* See hb_buffer_set_language().
*
* Return value: (transfer none):
* The #hb_language_t of the buffer. Must not be freed by the caller.
*
* Since: 0.9.2
**/
hb_language_t
hb_buffer_get_language (const hb_buffer_t *buffer)
{
return buffer->props.language;
}
/**
* hb_buffer_set_segment_properties:
* @buffer: An #hb_buffer_t
* @props: An #hb_segment_properties_t to use
*
* Sets the segment properties of the buffer, a shortcut for calling
* hb_buffer_set_direction(), hb_buffer_set_script() and
* hb_buffer_set_language() individually.
*
* Since: 0.9.7
**/
void
hb_buffer_set_segment_properties (hb_buffer_t *buffer,
const hb_segment_properties_t *props)
{
if (unlikely (hb_object_is_immutable (buffer)))
return;
buffer->props = *props;
}
/**
* hb_buffer_get_segment_properties:
* @buffer: An #hb_buffer_t
* @props: (out): The output #hb_segment_properties_t
*
* Sets @props to the #hb_segment_properties_t of @buffer.
*
* Since: 0.9.7
**/
void
hb_buffer_get_segment_properties (const hb_buffer_t *buffer,
hb_segment_properties_t *props)
{
*props = buffer->props;
}
/**
* hb_buffer_set_flags:
* @buffer: An #hb_buffer_t
* @flags: The buffer flags to set
*
* Sets @buffer flags to @flags. See #hb_buffer_flags_t.
*
* Since: 0.9.7
**/
void
hb_buffer_set_flags (hb_buffer_t *buffer,
hb_buffer_flags_t flags)
{
if (unlikely (hb_object_is_immutable (buffer)))
return;
buffer->flags = flags;
}
/**
* hb_buffer_get_flags:
* @buffer: An #hb_buffer_t
*
* Fetches the #hb_buffer_flags_t of @buffer.
*
* Return value:
* The @buffer flags
*
* Since: 0.9.7
**/
hb_buffer_flags_t
hb_buffer_get_flags (const hb_buffer_t *buffer)
{
return buffer->flags;
}
/**
* hb_buffer_set_cluster_level:
* @buffer: An #hb_buffer_t
* @cluster_level: The cluster level to set on the buffer
*
* Sets the cluster level of a buffer. The #hb_buffer_cluster_level_t
* dictates one aspect of how HarfBuzz will treat non-base characters
* during shaping.
*
* Since: 0.9.42
**/
void
hb_buffer_set_cluster_level (hb_buffer_t *buffer,
hb_buffer_cluster_level_t cluster_level)
{
if (unlikely (hb_object_is_immutable (buffer)))
return;
buffer->cluster_level = cluster_level;
}
/**
* hb_buffer_get_cluster_level:
* @buffer: An #hb_buffer_t
*
* Fetches the cluster level of a buffer. The #hb_buffer_cluster_level_t
* dictates one aspect of how HarfBuzz will treat non-base characters
* during shaping.
*
* Return value: The cluster level of @buffer
*
* Since: 0.9.42
**/
hb_buffer_cluster_level_t
hb_buffer_get_cluster_level (const hb_buffer_t *buffer)
{
return buffer->cluster_level;
}
/**
* hb_buffer_set_replacement_codepoint:
* @buffer: An #hb_buffer_t
* @replacement: the replacement #hb_codepoint_t
*
* Sets the #hb_codepoint_t that replaces invalid entries for a given encoding
* when adding text to @buffer.
*
* Default is #HB_BUFFER_REPLACEMENT_CODEPOINT_DEFAULT.
*
* Since: 0.9.31
**/
void
hb_buffer_set_replacement_codepoint (hb_buffer_t *buffer,
hb_codepoint_t replacement)
{
if (unlikely (hb_object_is_immutable (buffer)))
return;
buffer->replacement = replacement;
}
/**
* hb_buffer_get_replacement_codepoint:
* @buffer: An #hb_buffer_t
*
* Fetches the #hb_codepoint_t that replaces invalid entries for a given encoding
* when adding text to @buffer.
*
* Return value:
* The @buffer replacement #hb_codepoint_t
*
* Since: 0.9.31
**/
hb_codepoint_t
hb_buffer_get_replacement_codepoint (const hb_buffer_t *buffer)
{
return buffer->replacement;
}
/**
* hb_buffer_set_invisible_glyph:
* @buffer: An #hb_buffer_t
* @invisible: the invisible #hb_codepoint_t
*
* Sets the #hb_codepoint_t that replaces invisible characters in
* the shaping result. If set to zero (default), the glyph for the
* U+0020 SPACE character is used. Otherwise, this value is used
* verbatim.
*
* Since: 2.0.0
**/
void
hb_buffer_set_invisible_glyph (hb_buffer_t *buffer,
hb_codepoint_t invisible)
{
if (unlikely (hb_object_is_immutable (buffer)))
return;
buffer->invisible = invisible;
}
/**
* hb_buffer_get_invisible_glyph:
* @buffer: An #hb_buffer_t
*
* See hb_buffer_set_invisible_glyph().
*
* Return value:
* The @buffer invisible #hb_codepoint_t
*
* Since: 2.0.0
**/
hb_codepoint_t
hb_buffer_get_invisible_glyph (const hb_buffer_t *buffer)
{
return buffer->invisible;
}
/**
* hb_buffer_set_not_found_glyph:
* @buffer: An #hb_buffer_t
* @not_found: the not-found #hb_codepoint_t
*
* Sets the #hb_codepoint_t that replaces characters not found in
* the font during shaping.
*
* The not-found glyph defaults to zero, sometimes knows as the
* ".notdef" glyph. This API allows for differentiating the two.
*
* Since: 3.1.0
**/
void
hb_buffer_set_not_found_glyph (hb_buffer_t *buffer,
hb_codepoint_t not_found)
{
if (unlikely (hb_object_is_immutable (buffer)))
return;
buffer->not_found = not_found;
}
/**
* hb_buffer_get_not_found_glyph:
* @buffer: An #hb_buffer_t
*
* See hb_buffer_set_not_found_glyph().
*
* Return value:
* The @buffer not-found #hb_codepoint_t
*
* Since: 3.1.0
**/
hb_codepoint_t
hb_buffer_get_not_found_glyph (const hb_buffer_t *buffer)
{
return buffer->not_found;
}
/**
* hb_buffer_clear_contents:
* @buffer: An #hb_buffer_t
*
* Similar to hb_buffer_reset(), but does not clear the Unicode functions and
* the replacement code point.
*
* Since: 0.9.11
**/
void
hb_buffer_clear_contents (hb_buffer_t *buffer)
{
if (unlikely (hb_object_is_immutable (buffer)))
return;
buffer->clear ();
}
/**
* hb_buffer_pre_allocate:
* @buffer: An #hb_buffer_t
* @size: Number of items to pre allocate.
*
* Pre allocates memory for @buffer to fit at least @size number of items.
*
* Return value:
* %true if @buffer memory allocation succeeded, %false otherwise
*
* Since: 0.9.2
**/
hb_bool_t
hb_buffer_pre_allocate (hb_buffer_t *buffer, unsigned int size)
{
return buffer->ensure (size);
}
/**
* hb_buffer_allocation_successful:
* @buffer: An #hb_buffer_t
*
* Check if allocating memory for the buffer succeeded.
*
* Return value:
* %true if @buffer memory allocation succeeded, %false otherwise.
*
* Since: 0.9.2
**/
hb_bool_t
hb_buffer_allocation_successful (hb_buffer_t *buffer)
{
return buffer->successful;
}
/**
* hb_buffer_add:
* @buffer: An #hb_buffer_t
* @codepoint: A Unicode code point.
* @cluster: The cluster value of @codepoint.
*
* Appends a character with the Unicode value of @codepoint to @buffer, and
* gives it the initial cluster value of @cluster. Clusters can be any thing
* the client wants, they are usually used to refer to the index of the
* character in the input text stream and are output in
* #hb_glyph_info_t.cluster field.
*
* This function does not check the validity of @codepoint, it is up to the
* caller to ensure it is a valid Unicode code point.
*
* Since: 0.9.7
**/
void
hb_buffer_add (hb_buffer_t *buffer,
hb_codepoint_t codepoint,
unsigned int cluster)
{
buffer->add (codepoint, cluster);
buffer->clear_context (1);
}
/**
* hb_buffer_set_length:
* @buffer: An #hb_buffer_t
* @length: The new length of @buffer
*
* Similar to hb_buffer_pre_allocate(), but clears any new items added at the
* end.
*
* Return value:
* %true if @buffer memory allocation succeeded, %false otherwise.
*
* Since: 0.9.2
**/
hb_bool_t
hb_buffer_set_length (hb_buffer_t *buffer,
unsigned int length)
{
if (unlikely (hb_object_is_immutable (buffer)))
return length == 0;
if (unlikely (!buffer->ensure (length)))
return false;
/* Wipe the new space */
if (length > buffer->len) {
memset (buffer->info + buffer->len, 0, sizeof (buffer->info[0]) * (length - buffer->len));
if (buffer->have_positions)
memset (buffer->pos + buffer->len, 0, sizeof (buffer->pos[0]) * (length - buffer->len));
}
buffer->len = length;
if (!length)
{
buffer->content_type = HB_BUFFER_CONTENT_TYPE_INVALID;
buffer->clear_context (0);
}
buffer->clear_context (1);
return true;
}
/**
* hb_buffer_get_length:
* @buffer: An #hb_buffer_t
*
* Returns the number of items in the buffer.
*
* Return value:
* The @buffer length.
* The value valid as long as buffer has not been modified.
*
* Since: 0.9.2
**/
unsigned int
hb_buffer_get_length (const hb_buffer_t *buffer)
{
return buffer->len;
}
/**
* hb_buffer_get_glyph_infos:
* @buffer: An #hb_buffer_t
* @length: (out): The output-array length.
*
* Returns @buffer glyph information array. Returned pointer
* is valid as long as @buffer contents are not modified.
*
* Return value: (transfer none) (array length=length):
* The @buffer glyph information array.
* The value valid as long as buffer has not been modified.
*
* Since: 0.9.2
**/
hb_glyph_info_t *
hb_buffer_get_glyph_infos (hb_buffer_t *buffer,
unsigned int *length)
{
if (length)
*length = buffer->len;
return (hb_glyph_info_t *) buffer->info;
}
/**
* hb_buffer_get_glyph_positions:
* @buffer: An #hb_buffer_t
* @length: (out): The output length
*
* Returns @buffer glyph position array. Returned pointer
* is valid as long as @buffer contents are not modified.
*
* If buffer did not have positions before, the positions will be
* initialized to zeros, unless this function is called from
* within a buffer message callback (see hb_buffer_set_message_func()),
* in which case %NULL is returned.
*
* Return value: (transfer none) (array length=length):
* The @buffer glyph position array.
* The value valid as long as buffer has not been modified.
*
* Since: 0.9.2
**/
hb_glyph_position_t *
hb_buffer_get_glyph_positions (hb_buffer_t *buffer,
unsigned int *length)
{
if (length)
*length = buffer->len;
if (!buffer->have_positions)
{
if (unlikely (buffer->message_depth))
return nullptr;
buffer->clear_positions ();
}
return (hb_glyph_position_t *) buffer->pos;
}
/**
* hb_buffer_has_positions:
* @buffer: an #hb_buffer_t.
*
* Returns whether @buffer has glyph position data.
* A buffer gains position data when hb_buffer_get_glyph_positions() is called on it,
* and cleared of position data when hb_buffer_clear_contents() is called.
*
* Return value:
* %true if the @buffer has position array, %false otherwise.
*
* Since: 2.7.3
**/
HB_EXTERN hb_bool_t
hb_buffer_has_positions (hb_buffer_t *buffer)
{
return buffer->have_positions;
}
/**
* hb_glyph_info_get_glyph_flags:
* @info: a #hb_glyph_info_t
*
* Returns glyph flags encoded within a #hb_glyph_info_t.
*
* Return value:
* The #hb_glyph_flags_t encoded within @info
*
* Since: 1.5.0
**/
hb_glyph_flags_t
(hb_glyph_info_get_glyph_flags) (const hb_glyph_info_t *info)
{
return hb_glyph_info_get_glyph_flags (info);
}
/**
* hb_buffer_reverse:
* @buffer: An #hb_buffer_t
*
* Reverses buffer contents.
*
* Since: 0.9.2
**/
void
hb_buffer_reverse (hb_buffer_t *buffer)
{
buffer->reverse ();
}
/**
* hb_buffer_reverse_range:
* @buffer: An #hb_buffer_t
* @start: start index
* @end: end index
*
* Reverses buffer contents between @start and @end.
*
* Since: 0.9.41
**/
void
hb_buffer_reverse_range (hb_buffer_t *buffer,
unsigned int start, unsigned int end)
{
buffer->reverse_range (start, end);
}
/**
* hb_buffer_reverse_clusters:
* @buffer: An #hb_buffer_t
*
* Reverses buffer clusters. That is, the buffer contents are
* reversed, then each cluster (consecutive items having the
* same cluster number) are reversed again.
*
* Since: 0.9.2
**/
void
hb_buffer_reverse_clusters (hb_buffer_t *buffer)
{
buffer->reverse_clusters ();
}
/**
* hb_buffer_guess_segment_properties:
* @buffer: An #hb_buffer_t
*
* Sets unset buffer segment properties based on buffer Unicode
* contents. If buffer is not empty, it must have content type
* #HB_BUFFER_CONTENT_TYPE_UNICODE.
*
* If buffer script is not set (ie. is #HB_SCRIPT_INVALID), it
* will be set to the Unicode script of the first character in
* the buffer that has a script other than #HB_SCRIPT_COMMON,
* #HB_SCRIPT_INHERITED, and #HB_SCRIPT_UNKNOWN.
*
* Next, if buffer direction is not set (ie. is #HB_DIRECTION_INVALID),
* it will be set to the natural horizontal direction of the
* buffer script as returned by hb_script_get_horizontal_direction().
* If hb_script_get_horizontal_direction() returns #HB_DIRECTION_INVALID,
* then #HB_DIRECTION_LTR is used.
*
* Finally, if buffer language is not set (ie. is #HB_LANGUAGE_INVALID),
* it will be set to the process's default language as returned by
* hb_language_get_default(). This may change in the future by
* taking buffer script into consideration when choosing a language.
* Note that hb_language_get_default() is NOT threadsafe the first time
* it is called. See documentation for that function for details.
*
* Since: 0.9.7
**/
void
hb_buffer_guess_segment_properties (hb_buffer_t *buffer)
{
buffer->guess_segment_properties ();
}
template <typename utf_t>
static inline void
hb_buffer_add_utf (hb_buffer_t *buffer,
const typename utf_t::codepoint_t *text,
int text_length,
unsigned int item_offset,
int item_length)
{
typedef typename utf_t::codepoint_t T;
const hb_codepoint_t replacement = buffer->replacement;
buffer->assert_unicode ();
if (unlikely (hb_object_is_immutable (buffer)))
return;
if (text_length == -1)
text_length = utf_t::strlen (text);
if (item_length == -1)
item_length = text_length - item_offset;
if (unlikely (item_length < 0 ||
item_length > INT_MAX / 8 ||
!buffer->ensure (buffer->len + item_length * sizeof (T) / 4)))
return;
/* If buffer is empty and pre-context provided, install it.
* This check is written this way, to make sure people can
* provide pre-context in one add_utf() call, then provide
* text in a follow-up call. See:
*
* https://bugzilla.mozilla.org/show_bug.cgi?id=801410#c13
*/
if (!buffer->len && item_offset > 0)
{
/* Add pre-context */
buffer->clear_context (0);
const T *prev = text + item_offset;
const T *start = text;
while (start < prev && buffer->context_len[0] < buffer->CONTEXT_LENGTH)
{
hb_codepoint_t u;
prev = utf_t::prev (prev, start, &u, replacement);
buffer->context[0][buffer->context_len[0]++] = u;
}
}
const T *next = text + item_offset;
const T *end = next + item_length;
while (next < end)
{
hb_codepoint_t u;
const T *old_next = next;
next = utf_t::next (next, end, &u, replacement);
buffer->add (u, old_next - (const T *) text);
}
/* Add post-context */
buffer->clear_context (1);
end = text + text_length;
while (next < end && buffer->context_len[1] < buffer->CONTEXT_LENGTH)
{
hb_codepoint_t u;
next = utf_t::next (next, end, &u, replacement);
buffer->context[1][buffer->context_len[1]++] = u;
}
buffer->content_type = HB_BUFFER_CONTENT_TYPE_UNICODE;
}
/**
* hb_buffer_add_utf8:
* @buffer: An #hb_buffer_t
* @text: (array length=text_length) (element-type uint8_t): An array of UTF-8
* characters to append.
* @text_length: The length of the @text, or -1 if it is %NULL terminated.
* @item_offset: The offset of the first character to add to the @buffer.
* @item_length: The number of characters to add to the @buffer, or -1 for the
* end of @text (assuming it is %NULL terminated).
*
* See hb_buffer_add_codepoints().
*
* Replaces invalid UTF-8 characters with the @buffer replacement code point,
* see hb_buffer_set_replacement_codepoint().
*
* Since: 0.9.2
**/
void
hb_buffer_add_utf8 (hb_buffer_t *buffer,
const char *text,
int text_length,
unsigned int item_offset,
int item_length)
{
hb_buffer_add_utf<hb_utf8_t> (buffer, (const uint8_t *) text, text_length, item_offset, item_length);
}
/**
* hb_buffer_add_utf16:
* @buffer: An #hb_buffer_t
* @text: (array length=text_length): An array of UTF-16 characters to append
* @text_length: The length of the @text, or -1 if it is %NULL terminated
* @item_offset: The offset of the first character to add to the @buffer
* @item_length: The number of characters to add to the @buffer, or -1 for the
* end of @text (assuming it is %NULL terminated)
*
* See hb_buffer_add_codepoints().
*
* Replaces invalid UTF-16 characters with the @buffer replacement code point,
* see hb_buffer_set_replacement_codepoint().
*
* Since: 0.9.2
**/
void
hb_buffer_add_utf16 (hb_buffer_t *buffer,
const uint16_t *text,
int text_length,
unsigned int item_offset,
int item_length)
{
hb_buffer_add_utf<hb_utf16_t> (buffer, text, text_length, item_offset, item_length);
}
/**
* hb_buffer_add_utf32:
* @buffer: An #hb_buffer_t
* @text: (array length=text_length): An array of UTF-32 characters to append
* @text_length: The length of the @text, or -1 if it is %NULL terminated
* @item_offset: The offset of the first character to add to the @buffer
* @item_length: The number of characters to add to the @buffer, or -1 for the
* end of @text (assuming it is %NULL terminated)
*
* See hb_buffer_add_codepoints().
*
* Replaces invalid UTF-32 characters with the @buffer replacement code point,
* see hb_buffer_set_replacement_codepoint().
*
* Since: 0.9.2
**/
void
hb_buffer_add_utf32 (hb_buffer_t *buffer,
const uint32_t *text,
int text_length,
unsigned int item_offset,
int item_length)
{
hb_buffer_add_utf<hb_utf32_t> (buffer, text, text_length, item_offset, item_length);
}
/**
* hb_buffer_add_latin1:
* @buffer: An #hb_buffer_t
* @text: (array length=text_length) (element-type uint8_t): an array of UTF-8
* characters to append
* @text_length: the length of the @text, or -1 if it is %NULL terminated
* @item_offset: the offset of the first character to add to the @buffer
* @item_length: the number of characters to add to the @buffer, or -1 for the
* end of @text (assuming it is %NULL terminated)
*
* Similar to hb_buffer_add_codepoints(), but allows only access to first 256
* Unicode code points that can fit in 8-bit strings.
*
* <note>Has nothing to do with non-Unicode Latin-1 encoding.</note>
*
* Since: 0.9.39
**/
void
hb_buffer_add_latin1 (hb_buffer_t *buffer,
const uint8_t *text,
int text_length,
unsigned int item_offset,
int item_length)
{
hb_buffer_add_utf<hb_latin1_t> (buffer, text, text_length, item_offset, item_length);
}
/**
* hb_buffer_add_codepoints:
* @buffer: a #hb_buffer_t to append characters to.
* @text: (array length=text_length): an array of Unicode code points to append.
* @text_length: the length of the @text, or -1 if it is %NULL terminated.
* @item_offset: the offset of the first code point to add to the @buffer.
* @item_length: the number of code points to add to the @buffer, or -1 for the
* end of @text (assuming it is %NULL terminated).
*
* Appends characters from @text array to @buffer. The @item_offset is the
* position of the first character from @text that will be appended, and
* @item_length is the number of character. When shaping part of a larger text
* (e.g. a run of text from a paragraph), instead of passing just the substring
* corresponding to the run, it is preferable to pass the whole
* paragraph and specify the run start and length as @item_offset and
* @item_length, respectively, to give HarfBuzz the full context to be able,
* for example, to do cross-run Arabic shaping or properly handle combining
* marks at stat of run.
*
* This function does not check the validity of @text, it is up to the caller
* to ensure it contains a valid Unicode code points.
*
* Since: 0.9.31
**/
void
hb_buffer_add_codepoints (hb_buffer_t *buffer,
const hb_codepoint_t *text,
int text_length,
unsigned int item_offset,
int item_length)
{
hb_buffer_add_utf<hb_utf32_novalidate_t> (buffer, text, text_length, item_offset, item_length);
}
/**
* hb_buffer_append:
* @buffer: An #hb_buffer_t
* @source: source #hb_buffer_t
* @start: start index into source buffer to copy. Use 0 to copy from start of buffer.
* @end: end index into source buffer to copy. Use @HB_FEATURE_GLOBAL_END to copy to end of buffer.
*
* Append (part of) contents of another buffer to this buffer.
*
* Since: 1.5.0
**/
HB_EXTERN void
hb_buffer_append (hb_buffer_t *buffer,
const hb_buffer_t *source,
unsigned int start,
unsigned int end)
{
assert (!buffer->have_output && !source->have_output);
assert (buffer->have_positions == source->have_positions ||
!buffer->len || !source->len);
assert (buffer->content_type == source->content_type ||
!buffer->len || !source->len);
if (end > source->len)
end = source->len;
if (start > end)
start = end;
if (start == end)
return;
if (buffer->len + (end - start) < buffer->len) /* Overflows. */
{
buffer->successful = false;
return;
}
unsigned int orig_len = buffer->len;
hb_buffer_set_length (buffer, buffer->len + (end - start));
if (unlikely (!buffer->successful))
return;
if (!orig_len)
buffer->content_type = source->content_type;
if (!buffer->have_positions && source->have_positions)
buffer->clear_positions ();
hb_segment_properties_overlay (&buffer->props, &source->props);
memcpy (buffer->info + orig_len, source->info + start, (end - start) * sizeof (buffer->info[0]));
if (buffer->have_positions)
memcpy (buffer->pos + orig_len, source->pos + start, (end - start) * sizeof (buffer->pos[0]));
if (source->content_type == HB_BUFFER_CONTENT_TYPE_UNICODE)
{
/* See similar logic in add_utf. */
/* pre-context */
if (!orig_len && start + source->context_len[0] > 0)
{
buffer->clear_context (0);
while (start > 0 && buffer->context_len[0] < buffer->CONTEXT_LENGTH)
buffer->context[0][buffer->context_len[0]++] = source->info[--start].codepoint;
for (auto i = 0u; i < source->context_len[0] && buffer->context_len[0] < buffer->CONTEXT_LENGTH; i++)
buffer->context[0][buffer->context_len[0]++] = source->context[0][i];
}
/* post-context */
buffer->clear_context (1);
while (end < source->len && buffer->context_len[1] < buffer->CONTEXT_LENGTH)
buffer->context[1][buffer->context_len[1]++] = source->info[end++].codepoint;
for (auto i = 0u; i < source->context_len[1] && buffer->context_len[1] < buffer->CONTEXT_LENGTH; i++)
buffer->context[1][buffer->context_len[1]++] = source->context[1][i];
}
}
static int
compare_info_codepoint (const hb_glyph_info_t *pa,
const hb_glyph_info_t *pb)
{
return (int) pb->codepoint - (int) pa->codepoint;
}
static inline void
normalize_glyphs_cluster (hb_buffer_t *buffer,
unsigned int start,
unsigned int end,
bool backward)
{
hb_glyph_position_t *pos = buffer->pos;
/* Total cluster advance */
hb_position_t total_x_advance = 0, total_y_advance = 0;
for (unsigned int i = start; i < end; i++)
{
total_x_advance += pos[i].x_advance;
total_y_advance += pos[i].y_advance;
}
hb_position_t x_advance = 0, y_advance = 0;
for (unsigned int i = start; i < end; i++)
{
pos[i].x_offset += x_advance;
pos[i].y_offset += y_advance;
x_advance += pos[i].x_advance;
y_advance += pos[i].y_advance;
pos[i].x_advance = 0;
pos[i].y_advance = 0;
}
if (backward)
{
/* Transfer all cluster advance to the last glyph. */
pos[end - 1].x_advance = total_x_advance;
pos[end - 1].y_advance = total_y_advance;
hb_stable_sort (buffer->info + start, end - start - 1, compare_info_codepoint, buffer->pos + start);
} else {
/* Transfer all cluster advance to the first glyph. */
pos[start].x_advance += total_x_advance;
pos[start].y_advance += total_y_advance;
for (unsigned int i = start + 1; i < end; i++) {
pos[i].x_offset -= total_x_advance;
pos[i].y_offset -= total_y_advance;
}
hb_stable_sort (buffer->info + start + 1, end - start - 1, compare_info_codepoint, buffer->pos + start + 1);
}
}
/**
* hb_buffer_normalize_glyphs:
* @buffer: An #hb_buffer_t
*
* Reorders a glyph buffer to have canonical in-cluster glyph order / position.
* The resulting clusters should behave identical to pre-reordering clusters.
*
* <note>This has nothing to do with Unicode normalization.</note>
*
* Since: 0.9.2
**/
void
hb_buffer_normalize_glyphs (hb_buffer_t *buffer)
{
assert (buffer->have_positions);
buffer->assert_glyphs ();
bool backward = HB_DIRECTION_IS_BACKWARD (buffer->props.direction);
foreach_cluster (buffer, start, end)
normalize_glyphs_cluster (buffer, start, end, backward);
}
void
hb_buffer_t::sort (unsigned int start, unsigned int end, int(*compar)(const hb_glyph_info_t *, const hb_glyph_info_t *))
{
assert (!have_positions);
for (unsigned int i = start + 1; i < end; i++)
{
unsigned int j = i;
while (j > start && compar (&info[j - 1], &info[i]) > 0)
j--;
if (i == j)
continue;
/* Move item i to occupy place for item j, shift what's in between. */
merge_clusters (j, i + 1);
{
hb_glyph_info_t t = info[i];
memmove (&info[j + 1], &info[j], (i - j) * sizeof (hb_glyph_info_t));
info[j] = t;
}
}
}
/*
* Comparing buffers.
*/
/**
* hb_buffer_diff:
* @buffer: a buffer.
* @reference: other buffer to compare to.
* @dottedcircle_glyph: glyph id of U+25CC DOTTED CIRCLE, or (hb_codepont_t) -1.
* @position_fuzz: allowed absolute difference in position values.
*
* If dottedcircle_glyph is (hb_codepoint_t) -1 then #HB_BUFFER_DIFF_FLAG_DOTTED_CIRCLE_PRESENT
* and #HB_BUFFER_DIFF_FLAG_NOTDEF_PRESENT are never returned. This should be used by most
* callers if just comparing two buffers is needed.
*
* Since: 1.5.0
**/
hb_buffer_diff_flags_t
hb_buffer_diff (hb_buffer_t *buffer,
hb_buffer_t *reference,
hb_codepoint_t dottedcircle_glyph,
unsigned int position_fuzz)
{
if (buffer->content_type != reference->content_type && buffer->len && reference->len)
return HB_BUFFER_DIFF_FLAG_CONTENT_TYPE_MISMATCH;
hb_buffer_diff_flags_t result = HB_BUFFER_DIFF_FLAG_EQUAL;
bool contains = dottedcircle_glyph != (hb_codepoint_t) -1;
unsigned int count = reference->len;
if (buffer->len != count)
{
/*
* we can't compare glyph-by-glyph, but we do want to know if there
* are .notdef or dottedcircle glyphs present in the reference buffer
*/
const hb_glyph_info_t *info = reference->info;
unsigned int i;
for (i = 0; i < count; i++)
{
if (contains && info[i].codepoint == dottedcircle_glyph)
result |= HB_BUFFER_DIFF_FLAG_DOTTED_CIRCLE_PRESENT;
if (contains && info[i].codepoint == 0)
result |= HB_BUFFER_DIFF_FLAG_NOTDEF_PRESENT;
}
result |= HB_BUFFER_DIFF_FLAG_LENGTH_MISMATCH;
return hb_buffer_diff_flags_t (result);
}
if (!count)
return hb_buffer_diff_flags_t (result);
const hb_glyph_info_t *buf_info = buffer->info;
const hb_glyph_info_t *ref_info = reference->info;
for (unsigned int i = 0; i < count; i++)
{
if (buf_info->codepoint != ref_info->codepoint)
result |= HB_BUFFER_DIFF_FLAG_CODEPOINT_MISMATCH;
if (buf_info->cluster != ref_info->cluster)
result |= HB_BUFFER_DIFF_FLAG_CLUSTER_MISMATCH;
if ((buf_info->mask & ~ref_info->mask & HB_GLYPH_FLAG_DEFINED))
result |= HB_BUFFER_DIFF_FLAG_GLYPH_FLAGS_MISMATCH;
if (contains && ref_info->codepoint == dottedcircle_glyph)
result |= HB_BUFFER_DIFF_FLAG_DOTTED_CIRCLE_PRESENT;
if (contains && ref_info->codepoint == 0)
result |= HB_BUFFER_DIFF_FLAG_NOTDEF_PRESENT;
buf_info++;
ref_info++;
}
if (buffer->content_type == HB_BUFFER_CONTENT_TYPE_GLYPHS)
{
assert (buffer->have_positions);
const hb_glyph_position_t *buf_pos = buffer->pos;
const hb_glyph_position_t *ref_pos = reference->pos;
for (unsigned int i = 0; i < count; i++)
{
if ((unsigned int) abs (buf_pos->x_advance - ref_pos->x_advance) > position_fuzz ||
(unsigned int) abs (buf_pos->y_advance - ref_pos->y_advance) > position_fuzz ||
(unsigned int) abs (buf_pos->x_offset - ref_pos->x_offset) > position_fuzz ||
(unsigned int) abs (buf_pos->y_offset - ref_pos->y_offset) > position_fuzz)
{
result |= HB_BUFFER_DIFF_FLAG_POSITION_MISMATCH;
break;
}
buf_pos++;
ref_pos++;
}
}
return result;
}
/*
* Debugging.
*/
#ifndef HB_NO_BUFFER_MESSAGE
/**
* hb_buffer_set_message_func:
* @buffer: An #hb_buffer_t
* @func: (closure user_data) (destroy destroy) (scope notified): Callback function
* @user_data: (nullable): Data to pass to @func
* @destroy: (nullable): The function to call when @user_data is not needed anymore
*
* Sets the implementation function for #hb_buffer_message_func_t.
*
* Since: 1.1.3
**/
void
hb_buffer_set_message_func (hb_buffer_t *buffer,
hb_buffer_message_func_t func,
void *user_data, hb_destroy_func_t destroy)
{
if (buffer->message_destroy)
buffer->message_destroy (buffer->message_data);
if (func) {
buffer->message_func = func;
buffer->message_data = user_data;
buffer->message_destroy = destroy;
} else {
buffer->message_func = nullptr;
buffer->message_data = nullptr;
buffer->message_destroy = nullptr;
}
}
bool
hb_buffer_t::message_impl (hb_font_t *font, const char *fmt, va_list ap)
{
char buf[100];
vsnprintf (buf, sizeof (buf), fmt, ap);
return (bool) this->message_func (this, font, buf, this->message_data);
}
#endif
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