--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/harfbuzz/src/hb-ms-feature-ranges.hh	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,229 @@
+/*
+ * Copyright © 2011,2012,2013  Google, Inc.
+ * Copyright © 2021  Khaled Hosny
+ *
+ *  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
+ */
+
+#ifndef HB_MS_FEATURE_RANGES_HH
+#define HB_MS_FEATURE_RANGES_HH
+
+#include "hb.hh"
+
+typedef struct hb_ms_feature_t {
+  uint32_t tag_le;
+  uint32_t value;
+} hb_ms_feature_t;
+
+typedef struct hb_ms_features_t {
+  hb_ms_feature_t *features;
+  uint32_t         num_features;
+} hb_ms_features_t;
+
+struct hb_ms_active_feature_t {
+  hb_ms_feature_t fea;
+  unsigned int order;
+
+  HB_INTERNAL static int cmp (const void *pa, const void *pb) {
+    const auto *a = (const hb_ms_active_feature_t *) pa;
+    const auto *b = (const hb_ms_active_feature_t *) pb;
+    return a->fea.tag_le < b->fea.tag_le ? -1 : a->fea.tag_le > b->fea.tag_le ? 1 :
+	   a->order < b->order ? -1 : a->order > b->order ? 1 :
+	   a->fea.value < b->fea.value ? -1 : a->fea.value > b->fea.value ? 1 :
+	   0;
+  }
+  bool operator== (const hb_ms_active_feature_t& f) const
+  { return cmp (this, &f) == 0; }
+};
+
+struct hb_ms_feature_event_t {
+  unsigned int index;
+  bool start;
+  hb_ms_active_feature_t feature;
+
+  HB_INTERNAL static int cmp (const void *pa, const void *pb)
+  {
+    const auto *a = (const hb_ms_feature_event_t *) pa;
+    const auto *b = (const hb_ms_feature_event_t *) pb;
+    return a->index < b->index ? -1 : a->index > b->index ? 1 :
+	   a->start < b->start ? -1 : a->start > b->start ? 1 :
+	   hb_ms_active_feature_t::cmp (&a->feature, &b->feature);
+  }
+};
+
+struct hb_ms_range_record_t {
+  hb_ms_features_t features;
+  unsigned int index_first; /* == start */
+  unsigned int index_last;  /* == end - 1 */
+};
+
+static inline bool
+hb_ms_setup_features (const hb_feature_t                *features,
+		      unsigned int                       num_features,
+		      hb_vector_t<hb_ms_feature_t>      &feature_records, /* OUT */
+		      hb_vector_t<hb_ms_range_record_t> &range_records /* OUT */)
+{
+  feature_records.shrink(0);
+  range_records.shrink(0);
+
+  /* Sort features by start/end events. */
+  hb_vector_t<hb_ms_feature_event_t> feature_events;
+  for (unsigned int i = 0; i < num_features; i++)
+  {
+    hb_ms_active_feature_t feature;
+    feature.fea.tag_le = hb_uint32_swap (features[i].tag);
+    feature.fea.value = features[i].value;
+    feature.order = i;
+
+    hb_ms_feature_event_t *event;
+
+    event = feature_events.push ();
+    event->index = features[i].start;
+    event->start = true;
+    event->feature = feature;
+
+    event = feature_events.push ();
+    event->index = features[i].end;
+    event->start = false;
+    event->feature = feature;
+  }
+  feature_events.qsort ();
+  /* Add a strategic final event. */
+  {
+    hb_ms_active_feature_t feature;
+    feature.fea.tag_le = 0;
+    feature.fea.value = 0;
+    feature.order = num_features + 1;
+
+    auto *event = feature_events.push ();
+    event->index = 0; /* This value does magic. */
+    event->start = false;
+    event->feature = feature;
+  }
+
+  /* Scan events and save features for each range. */
+  hb_vector_t<hb_ms_active_feature_t> active_features;
+  unsigned int last_index = 0;
+  for (unsigned int i = 0; i < feature_events.length; i++)
+  {
+    auto *event = &feature_events[i];
+
+    if (event->index != last_index)
+    {
+      /* Save a snapshot of active features and the range. */
+      auto *range = range_records.push ();
+      auto offset = feature_records.length;
+
+      active_features.qsort ();
+      for (unsigned int j = 0; j < active_features.length; j++)
+      {
+        if (!j || active_features[j].fea.tag_le != feature_records[feature_records.length - 1].tag_le)
+        {
+          feature_records.push (active_features[j].fea);
+        }
+        else
+        {
+          /* Overrides value for existing feature. */
+          feature_records[feature_records.length - 1].value = active_features[j].fea.value;
+        }
+      }
+
+      /* Will convert to pointer after all is ready, since feature_records.array
+       * may move as we grow it. */
+      range->features.features = reinterpret_cast<hb_ms_feature_t *> (offset);
+      range->features.num_features = feature_records.length - offset;
+      range->index_first = last_index;
+      range->index_last  = event->index - 1;
+
+      last_index = event->index;
+    }
+
+    if (event->start)
+    {
+      active_features.push (event->feature);
+    }
+    else
+    {
+      auto *feature = active_features.lsearch (event->feature);
+      if (feature)
+        active_features.remove_ordered (feature - active_features.arrayZ);
+    }
+  }
+
+  if (!range_records.length) /* No active feature found. */
+    num_features = 0;
+
+  /* Fixup the pointers. */
+  for (unsigned int i = 0; i < range_records.length; i++)
+  {
+    auto *range = &range_records[i];
+    range->features.features = (hb_ms_feature_t *) feature_records + reinterpret_cast<uintptr_t> (range->features.features);
+  }
+
+  return !!num_features;
+}
+
+static inline void
+hb_ms_make_feature_ranges (hb_vector_t<hb_ms_feature_t>      &feature_records,
+			   hb_vector_t<hb_ms_range_record_t> &range_records,
+			   unsigned int                       chars_offset,
+			   unsigned int                       chars_len,
+			   uint16_t                          *log_clusters,
+			   hb_vector_t<hb_ms_features_t*>    &range_features, /* OUT */
+			   hb_vector_t<uint32_t>             &range_counts /* OUT */)
+{
+  range_features.shrink (0);
+  range_counts.shrink (0);
+
+  auto *last_range = &range_records[0];
+  for (unsigned int i = chars_offset; i < chars_len; i++)
+  {
+    auto *range = last_range;
+    while (log_clusters[i] < range->index_first)
+      range--;
+    while (log_clusters[i] > range->index_last)
+      range++;
+    if (!range_features.length ||
+        &range->features != range_features[range_features.length - 1])
+    {
+      auto **features = range_features.push ();
+      auto *c = range_counts.push ();
+      if (unlikely (!features || !c))
+      {
+        range_features.shrink (0);
+        range_counts.shrink (0);
+        break;
+      }
+      *features = &range->features;
+      *c = 1;
+    }
+    else
+    {
+      range_counts[range_counts.length - 1]++;
+    }
+
+    last_range = range;
+  }
+}
+
+#endif /* HB_MS_FEATURE_RANGES_HH */