/* * 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 ^ (unsigned int) p->script ^ (intptr_t) (p->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, swap_buffers() is 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. swap_buffers() then * switches info and out_info. */ /* 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 *) realloc (pos, new_allocated * sizeof (pos[0])); new_info = (hb_glyph_info_t *) 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::reset () { hb_unicode_funcs_destroy (unicode); unicode = hb_unicode_funcs_reference (hb_unicode_funcs_get_default ()); flags = HB_BUFFER_FLAG_DEFAULT; replacement = HB_BUFFER_REPLACEMENT_CODEPOINT_DEFAULT; invisible = 0; clear (); } void hb_buffer_t::clear () { hb_segment_properties_t default_props = HB_SEGMENT_PROPERTIES_DEFAULT; props = default_props; scratch_flags = HB_BUFFER_SCRATCH_FLAG_DEFAULT; content_type = HB_BUFFER_CONTENT_TYPE_INVALID; successful = true; have_output = false; have_positions = false; idx = 0; len = 0; out_len = 0; out_info = info; serial = 0; memset (context, 0, sizeof context); memset (context_len, 0, sizeof context_len); deallocate_var_all (); } 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::remove_output () { have_output = false; have_positions = false; out_len = 0; out_info = info; } void hb_buffer_t::clear_output () { have_output = true; have_positions = false; 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::swap_buffers () { if (unlikely (!successful)) return; assert (idx <= len); if (unlikely (!next_glyphs (len - idx))) return; assert (have_output); have_output = false; if (out_info != info) { hb_glyph_info_t *tmp; tmp = info; info = out_info; out_info = tmp; pos = (hb_glyph_position_t *) out_info; } unsigned int tmp; tmp = len; len = out_len; out_len = tmp; 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, instead of the 0 below. * But that would leave empty slots in the buffer in case of allocation * failures. Setting to zero for now to avoid other problems (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 + 0))) 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::reverse_range (unsigned int start, unsigned int end) { if (end - start < 2) return; hb_array_t (info, len).reverse (start, end); if (have_positions) { hb_array_t (pos, len).reverse (start, end); } } void hb_buffer_t::reverse () { if (unlikely (!len)) return; reverse_range (0, len); } void hb_buffer_t::reverse_clusters () { unsigned int i, start, count, last_cluster; if (unlikely (!len)) return; reverse (); count = len; start = 0; last_cluster = info[0].cluster; for (i = 1; i < count; i++) { if (last_cluster != info[i].cluster) { reverse_range (start, i); start = i; last_cluster = info[i].cluster; } } reverse_range (start, i); } 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) { /* Cluster survives; do nothing. */ goto done; } 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::unsafe_to_break_impl (unsigned int start, unsigned int end) { unsigned int cluster = UINT_MAX; cluster = _unsafe_to_break_find_min_cluster (info, start, end, cluster); _unsafe_to_break_set_mask (info, start, end, cluster); } void hb_buffer_t::unsafe_to_break_from_outbuffer (unsigned int start, unsigned int end) { if (!have_output) { unsafe_to_break_impl (start, end); return; } assert (start <= out_len); assert (idx <= end); unsigned int cluster = UINT_MAX; cluster = _unsafe_to_break_find_min_cluster (out_info, start, out_len, cluster); cluster = _unsafe_to_break_find_min_cluster (info, idx, end, cluster); _unsafe_to_break_set_mask (out_info, start, out_len, cluster); _unsafe_to_break_set_mask (info, idx, end, cluster); } 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_Null_hb_unicode_funcs_t), HB_BUFFER_FLAG_DEFAULT, HB_BUFFER_CLUSTER_LEVEL_DEFAULT, HB_BUFFER_REPLACEMENT_CODEPOINT_DEFAULT, 0, /* invisible */ HB_BUFFER_SCRATCH_FLAG_DEFAULT, HB_BUFFER_MAX_LEN_DEFAULT, HB_BUFFER_MAX_OPS_DEFAULT, HB_BUFFER_CONTENT_TYPE_INVALID, HB_SEGMENT_PROPERTIES_DEFAULT, false, /* successful */ true, /* have_output */ true /* have_positions */ /* Zero is good enough for everything else. */ }; /** * hb_buffer_create: (Xconstructor) * * 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 ())) 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_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 (&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); free (buffer->info); free (buffer->pos); #ifndef HB_NO_BUFFER_MESSAGE if (buffer->message_destroy) buffer->message_destroy (buffer->message_data); #endif 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 (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 (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 (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 (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 (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 (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 (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 (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 (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 (hb_buffer_t *buffer) { return buffer->invisible; } /** * 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_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 (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. * * 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 (!buffer->have_positions) buffer->clear_positions (); if (length) *length = buffer->len; 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 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 (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 (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 (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. * * Has nothing to do with non-Unicode Latin-1 encoding. * * 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 (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 (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, 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 (); 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])); } 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. * * This has nothing to do with Unicode normalization. * * 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