harfbuzz: check in harfbuzz-ng, add gyp define to use it

third_party/harfbuzz-ng/src/hb-ot-shape-complex-arabic.cc

+/*
+ * Copyright (C) 2010  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.
+ *
+ * Google Author(s): Behdad Esfahbod
+ */
+
+#include "hb-ot-shape-complex-private.hh"
+
+HB_BEGIN_DECLS
+
+
+/* buffer var allocations */
+#define arabic_shaping_action() var2.u32 /* arabic shaping action */
+
+
+/*
+ * Bits used in the joining tables
+ */
+enum {
+  JOINING_TYPE_U                = 0,
+  JOINING_TYPE_R                = 1,
+  JOINING_TYPE_D                = 2,
+  JOINING_TYPE_C                = JOINING_TYPE_D,
+  JOINING_GROUP_ALAPH           = 3,
+  JOINING_GROUP_DALATH_RISH     = 4,
+  NUM_STATE_MACHINE_COLS        = 5,
+
+  /* We deliberately don't have a JOINING_TYPE_L since that's unused in Unicode. */
+
+  JOINING_TYPE_T = 6,
+  JOINING_TYPE_X = 7  /* means: use general-category to choose between U or T. */
+};
+
+/*
+ * Joining types:
+ */
+
+#include "hb-ot-shape-complex-arabic-table.h"
+
+static unsigned int get_joining_type (hb_codepoint_t u, hb_category_t gen_cat)
+{
+  /* TODO Macroize the magic bit operations */
+
+  if (likely (JOINING_TABLE_FIRST <= u && u <= JOINING_TABLE_LAST)) {
+    unsigned int j_type = joining_table[u - JOINING_TABLE_FIRST];
+    if (likely (j_type != JOINING_TYPE_X))
+      return j_type;
+  }
+
+  /* Mongolian joining data is not in ArabicJoining.txt yet */
+  if (unlikely (0x1800 <= u && u <= 0x18AF))
+  {
+    /* All letters, SIBE SYLLABLE BOUNDARY MARKER, and NIRUGU are D */
+    if (gen_cat == HB_CATEGORY_OTHER_LETTER || u == 0x1807 || u == 0x180A)
+      return JOINING_TYPE_D;
+  }
+
+  if (unlikely ((u & ~(0x200C^0x200D)) == 0x200C)) {
+    return u == 0x200C ? JOINING_TYPE_U : JOINING_TYPE_C;
+  }
+
+  return ((1<<gen_cat) & ((1<<HB_CATEGORY_NON_SPACING_MARK)|(1<<HB_CATEGORY_ENCLOSING_MARK)|(1<<HB_CATEGORY_FORMAT))) ?
+         JOINING_TYPE_T : JOINING_TYPE_U;
+}
+
+
+
+static const hb_tag_t arabic_syriac_features[] =
+{
+  HB_TAG('i','n','i','t'),
+  HB_TAG('m','e','d','i'),
+  HB_TAG('f','i','n','a'),
+  HB_TAG('i','s','o','l'),
+  /* Syriac */
+  HB_TAG('m','e','d','2'),
+  HB_TAG('f','i','n','2'),
+  HB_TAG('f','i','n','3'),
+  HB_TAG_NONE
+};
+
+
+/* Same order as the feature array */
+enum {
+  INIT,
+  MEDI,
+  FINA,
+  ISOL,
+
+  /* Syriac */
+  MED2,
+  FIN2,
+  FIN3,
+
+  NONE,
+
+  COMMON_NUM_FEATURES = 4,
+  SYRIAC_NUM_FEATURES = 7,
+  TOTAL_NUM_FEATURES = NONE
+};
+
+static const struct arabic_state_table_entry {
+        uint8_t prev_action;
+        uint8_t curr_action;
+        uint8_t next_state;
+        uint8_t padding;
+} arabic_state_table[][NUM_STATE_MACHINE_COLS] =
+{
+  /*   jt_U,          jt_R,          jt_D,          jg_ALAPH,      jg_DALATH_RISH */
+
+  /* State 0: prev was U, not willing to join. */
+  { {NONE,NONE,0}, {NONE,ISOL,1}, {NONE,ISOL,2}, {NONE,ISOL,1}, {NONE,ISOL,6}, },
+
+  /* State 1: prev was R or ISOL/ALAPH, not willing to join. */
+  { {NONE,NONE,0}, {NONE,ISOL,1}, {NONE,ISOL,2}, {NONE,FIN2,5}, {NONE,ISOL,6}, },
+
+  /* State 2: prev was D/ISOL, willing to join. */
+  { {NONE,NONE,0}, {INIT,FINA,1}, {INIT,FINA,3}, {INIT,FINA,4}, {INIT,FINA,6}, },
+
+  /* State 3: prev was D/FINA, willing to join. */
+  { {NONE,NONE,0}, {MEDI,FINA,1}, {MEDI,FINA,3}, {MEDI,FINA,4}, {MEDI,FINA,6}, },
+
+  /* State 4: prev was FINA ALAPH, not willing to join. */
+  { {NONE,NONE,0}, {MED2,ISOL,1}, {MED2,ISOL,2}, {MED2,FIN2,5}, {MED2,ISOL,6}, },
+
+  /* State 5: prev was FIN2/FIN3 ALAPH, not willing to join. */
+  { {NONE,NONE,0}, {ISOL,ISOL,1}, {ISOL,ISOL,2}, {ISOL,FIN2,5}, {ISOL,ISOL,6}, },
+
+  /* State 6: prev was DALATH/RISH, not willing to join. */
+  { {NONE,NONE,0}, {NONE,ISOL,1}, {NONE,ISOL,2}, {NONE,FIN3,5}, {NONE,ISOL,6}, }
+};
+
+
+
+void
+_hb_ot_shape_complex_collect_features_arabic    (hb_ot_shape_plan_t *plan, const hb_segment_properties_t  *props)
+{
+  unsigned int num_features = props->script == HB_SCRIPT_SYRIAC ? SYRIAC_NUM_FEATURES : COMMON_NUM_FEATURES;
+  for (unsigned int i = 0; i < num_features; i++)
+    plan->map.add_bool_feature (arabic_syriac_features[i], false);
+}
+
+void
+_hb_ot_shape_complex_setup_masks_arabic (hb_ot_shape_context_t *c)
+{
+  unsigned int count = c->buffer->len;
+  unsigned int prev = 0, state = 0;
+
+  for (unsigned int i = 0; i < count; i++)
+  {
+    unsigned int this_type = get_joining_type (c->buffer->info[i].codepoint, (hb_category_t) c->buffer->info[i].general_category());
+
+    if (unlikely (this_type == JOINING_TYPE_T)) {
+      c->buffer->info[i].arabic_shaping_action() = NONE;
+      continue;
+    }
+
+    const arabic_state_table_entry *entry = &arabic_state_table[state][this_type];
+
+    if (entry->prev_action != NONE)
+      c->buffer->info[prev].arabic_shaping_action() = entry->prev_action;
+
+    c->buffer->info[i].arabic_shaping_action() = entry->curr_action;
+
+    prev = i;
+    state = entry->next_state;
+  }
+
+  hb_mask_t mask_array[TOTAL_NUM_FEATURES + 1] = {0};
+  unsigned int num_masks = c->buffer->props.script == HB_SCRIPT_SYRIAC ? SYRIAC_NUM_FEATURES : COMMON_NUM_FEATURES;
+  for (unsigned int i = 0; i < num_masks; i++)
+    mask_array[i] = c->plan->map.get_1_mask (arabic_syriac_features[i]);
+
+  for (unsigned int i = 0; i < count; i++)
+    c->buffer->info[i].mask |= mask_array[c->buffer->info[i].arabic_shaping_action()];
+}
+
+
+HB_END_DECLS