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Diffstat (limited to 'gfx/harfbuzz/src/hb-buffer.cc')
-rw-r--r-- | gfx/harfbuzz/src/hb-buffer.cc | 2222 |
1 files changed, 2222 insertions, 0 deletions
diff --git a/gfx/harfbuzz/src/hb-buffer.cc b/gfx/harfbuzz/src/hb-buffer.cc new file mode 100644 index 0000000000..934c6c2129 --- /dev/null +++ b/gfx/harfbuzz/src/hb-buffer.cc @@ -0,0 +1,2222 @@ +/* + * 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. + * + * The input buffer is a sequence of Unicode codepoints, with + * associated attributes such as direction and script. The output + * buffer is a sequence of glyphs, with associated attributes such + * as position and cluster. + **/ + + +/** + * 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; + + unsigned new_bytes; + if (unlikely (hb_unsigned_mul_overflows (new_allocated, sizeof (info[0]), &new_bytes))) + goto done; + + static_assert (sizeof (info[0]) == sizeof (pos[0]), ""); + new_pos = (hb_glyph_position_t *) hb_realloc (pos, new_bytes); + new_info = (hb_glyph_info_t *) hb_realloc (info, new_bytes); + +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; + hb_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... */ + hb_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.replacement; + 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; + + hb_memset (context, 0, sizeof context); + hb_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; + unsigned mul; + if (likely (!hb_unsigned_mul_overflows (len, HB_BUFFER_MAX_LEN_FACTOR, &mul))) + { + max_len = hb_max (mul, (unsigned) HB_BUFFER_MAX_LEN_MIN); + } + if (likely (!hb_unsigned_mul_overflows (len, HB_BUFFER_MAX_OPS_FACTOR, &mul))) + { + max_ops = hb_max (mul, (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]; + + hb_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); +} + +bool +hb_buffer_t::sync () +{ + bool ret = false; + + 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; + ret = true; + +reset: + have_output = false; + out_len = 0; + out_info = info; + idx = 0; + + return ret; +} + +int +hb_buffer_t::sync_so_far () +{ + bool had_output = have_output; + unsigned out_i = out_len; + unsigned i = idx; + unsigned old_idx = idx; + + if (sync ()) + idx = out_i; + else + idx = i; + + if (had_output) + { + have_output = true; + out_len = idx; + } + + assert (idx <= len); + + return idx - old_idx; +} + +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) +{ + if (!mask) + return; + + hb_mask_t not_mask = ~mask; + value &= mask; + + 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 */ + if (cluster != info[end - 1].cluster) + while (end < len && info[end - 1].cluster == info[end].cluster) + end++; + + /* Extend start */ + if (cluster != info[start].cluster) + 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 && info[start].cluster != cluster) + 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; + } + + 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::delete_glyphs_inplace (bool (*filter) (const hb_glyph_info_t *info)) +{ + /* Merge clusters and delete filtered glyphs. + * NOTE! We can't use out-buffer as we have positioning data. */ + unsigned int j = 0; + unsigned int count = len; + for (unsigned int i = 0; i < count; i++) + { + if (filter (&info[i])) + { + /* Merge clusters. + * Same logic as delete_glyph(), but for in-place removal. */ + + unsigned int cluster = info[i].cluster; + if (i + 1 < count && cluster == info[i + 1].cluster) + continue; /* Cluster survives; do nothing. */ + + if (j) + { + /* Merge cluster backward. */ + if (cluster < info[j - 1].cluster) + { + unsigned int mask = info[i].mask; + unsigned int old_cluster = info[j - 1].cluster; + for (unsigned k = j; k && info[k - 1].cluster == old_cluster; k--) + set_cluster (info[k - 1], cluster, mask); + } + continue; + } + + if (i + 1 < count) + merge_clusters (i, i + 2); /* Merge cluster forward. */ + + continue; + } + + if (j != i) + { + info[j] = info[i]; + pos[j] = pos[i]; + } + j++; + } + len = j; +} + +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 (const 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). + * + * You rarely need to call this function, since a number of other + * functions transition the content type for you. Namely: + * + * - A newly created buffer starts with content type + * %HB_BUFFER_CONTENT_TYPE_INVALID. Calling hb_buffer_reset(), + * hb_buffer_clear_contents(), as well as calling hb_buffer_set_length() + * with an argument of zero all set the buffer content type to invalid + * as well. + * + * - Calling hb_buffer_add_utf8(), hb_buffer_add_utf16(), + * hb_buffer_add_utf32(), hb_buffer_add_codepoints() and + * hb_buffer_add_latin1() expect that buffer is either empty and + * have a content type of invalid, or that buffer content type is + * %HB_BUFFER_CONTENT_TYPE_UNICODE, and they also set the content + * type to Unicode if they added anything to an empty buffer. + * + * - Finally hb_shape() and hb_shape_full() expect that the buffer + * is either empty and have content type of invalid, or that buffer + * content type is %HB_BUFFER_CONTENT_TYPE_UNICODE, and upon + * success they set the buffer content type to + * %HB_BUFFER_CONTENT_TYPE_GLYPHS. + * + * The above transitions are designed such that one can use a buffer + * in a loop of "reset : add-text : shape" without needing to ever + * modify the content type manually. + * + * 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 known 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) { + hb_memset (buffer->info + buffer->len, 0, sizeof (buffer->info[0]) * (length - buffer->len)); + if (buffer->have_positions) + hb_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 scalar values. In contrast, + * hb_buffer_add_utf32() can be used that takes similar input but performs + * sanity-check on the input. + * + * 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); + + hb_memcpy (buffer->info + orig_len, source->info + start, (end - start) * sizeof (buffer->info[0])); + if (buffer->have_positions) + hb_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_codepoint_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 (unlikely (hb_object_is_immutable (buffer))) + { + if (destroy) + destroy (user_data); + return; + } + + 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) +{ + assert (!have_output || (out_info == info && out_len == idx)); + + message_depth++; + + char buf[100]; + vsnprintf (buf, sizeof (buf), fmt, ap); + bool ret = (bool) this->message_func (this, font, buf, this->message_data); + + message_depth--; + + return ret; +} +#endif |