HarfBuzz: Update to version 4.4.1

1 files changed, 216 insertions, 0 deletions

diff --git a/thirdparty/harfbuzz/src/OT/glyf/SimpleGlyph.hh b/thirdparty/harfbuzz/src/OT/glyf/SimpleGlyph.hh
new file mode 100644
index 0000000000..6df978cf13
--- /dev/null
+++ b/thirdparty/harfbuzz/src/OT/glyf/SimpleGlyph.hh
@@ -0,0 +1,216 @@
+#ifndef OT_GLYF_SIMPLEGLYPH_HH
+#define OT_GLYF_SIMPLEGLYPH_HH
+
+
+#include "../../hb-open-type.hh"
+
+
+namespace OT {
+namespace glyf_impl {
+
+
+struct SimpleGlyph
+{
+  enum simple_glyph_flag_t
+  {
+    FLAG_ON_CURVE       = 0x01,
+    FLAG_X_SHORT        = 0x02,
+    FLAG_Y_SHORT        = 0x04,
+    FLAG_REPEAT         = 0x08,
+    FLAG_X_SAME         = 0x10,
+    FLAG_Y_SAME         = 0x20,
+    FLAG_OVERLAP_SIMPLE = 0x40,
+    FLAG_RESERVED2      = 0x80
+  };
+
+  const GlyphHeader &header;
+  hb_bytes_t bytes;
+  SimpleGlyph (const GlyphHeader &header_, hb_bytes_t bytes_) :
+    header (header_), bytes (bytes_) {}
+
+  unsigned int instruction_len_offset () const
+  { return GlyphHeader::static_size + 2 * header.numberOfContours; }
+
+  unsigned int length (unsigned int instruction_len) const
+  { return instruction_len_offset () + 2 + instruction_len; }
+
+  unsigned int instructions_length () const
+  {
+    unsigned int instruction_length_offset = instruction_len_offset ();
+    if (unlikely (instruction_length_offset + 2 > bytes.length)) return 0;
+
+    const HBUINT16 &instructionLength = StructAtOffset<HBUINT16> (&bytes, instruction_length_offset);
+    /* Out of bounds of the current glyph */
+    if (unlikely (length (instructionLength) > bytes.length)) return 0;
+    return instructionLength;
+  }
+
+  const hb_bytes_t trim_padding () const
+  {
+    /* based on FontTools _g_l_y_f.py::trim */
+    const uint8_t *glyph = (uint8_t*) bytes.arrayZ;
+    const uint8_t *glyph_end = glyph + bytes.length;
+    /* simple glyph w/contours, possibly trimmable */
+    glyph += instruction_len_offset ();
+
+    if (unlikely (glyph + 2 >= glyph_end)) return hb_bytes_t ();
+    unsigned int num_coordinates = StructAtOffset<HBUINT16> (glyph - 2, 0) + 1;
+    unsigned int num_instructions = StructAtOffset<HBUINT16> (glyph, 0);
+
+    glyph += 2 + num_instructions;
+
+    unsigned int coord_bytes = 0;
+    unsigned int coords_with_flags = 0;
+    while (glyph < glyph_end)
+    {
+      uint8_t flag = *glyph;
+      glyph++;
+
+      unsigned int repeat = 1;
+      if (flag & FLAG_REPEAT)
+      {
+	if (unlikely (glyph >= glyph_end)) return hb_bytes_t ();
+	repeat = *glyph + 1;
+	glyph++;
+      }
+
+      unsigned int xBytes, yBytes;
+      xBytes = yBytes = 0;
+      if (flag & FLAG_X_SHORT) xBytes = 1;
+      else if ((flag & FLAG_X_SAME) == 0) xBytes = 2;
+
+      if (flag & FLAG_Y_SHORT) yBytes = 1;
+      else if ((flag & FLAG_Y_SAME) == 0) yBytes = 2;
+
+      coord_bytes += (xBytes + yBytes) * repeat;
+      coords_with_flags += repeat;
+      if (coords_with_flags >= num_coordinates) break;
+    }
+
+    if (unlikely (coords_with_flags != num_coordinates)) return hb_bytes_t ();
+    return bytes.sub_array (0, bytes.length + coord_bytes - (glyph_end - glyph));
+  }
+
+  /* zero instruction length */
+  void drop_hints ()
+  {
+    GlyphHeader &glyph_header = const_cast<GlyphHeader &> (header);
+    (HBUINT16 &) StructAtOffset<HBUINT16> (&glyph_header, instruction_len_offset ()) = 0;
+  }
+
+  void drop_hints_bytes (hb_bytes_t &dest_start, hb_bytes_t &dest_end) const
+  {
+    unsigned int instructions_len = instructions_length ();
+    unsigned int glyph_length = length (instructions_len);
+    dest_start = bytes.sub_array (0, glyph_length - instructions_len);
+    dest_end = bytes.sub_array (glyph_length, bytes.length - glyph_length);
+  }
+
+  void set_overlaps_flag ()
+  {
+    if (unlikely (!header.numberOfContours)) return;
+
+    unsigned flags_offset = length (instructions_length ());
+    if (unlikely (flags_offset + 1 > bytes.length)) return;
+
+    HBUINT8 &first_flag = (HBUINT8 &) StructAtOffset<HBUINT16> (&bytes, flags_offset);
+    first_flag = (uint8_t) first_flag | FLAG_OVERLAP_SIMPLE;
+  }
+
+  static bool read_flags (const HBUINT8 *&p /* IN/OUT */,
+			  contour_point_vector_t &points_ /* IN/OUT */,
+			  const HBUINT8 *end)
+  {
+    unsigned count = points_.length;
+    for (unsigned int i = 0; i < count;)
+    {
+      if (unlikely (p + 1 > end)) return false;
+      uint8_t flag = *p++;
+      points_.arrayZ[i++].flag = flag;
+      if (flag & FLAG_REPEAT)
+      {
+	if (unlikely (p + 1 > end)) return false;
+	unsigned int repeat_count = *p++;
+	unsigned stop = hb_min (i + repeat_count, count);
+	for (; i < stop;)
+	  points_.arrayZ[i++].flag = flag;
+      }
+    }
+    return true;
+  }
+
+  static bool read_points (const HBUINT8 *&p /* IN/OUT */,
+			   contour_point_vector_t &points_ /* IN/OUT */,
+			   const HBUINT8 *end,
+			   float contour_point_t::*m,
+			   const simple_glyph_flag_t short_flag,
+			   const simple_glyph_flag_t same_flag)
+  {
+    int v = 0;
+
+    unsigned count = points_.length;
+    for (unsigned i = 0; i < count; i++)
+    {
+      unsigned flag = points_[i].flag;
+      if (flag & short_flag)
+      {
+	if (unlikely (p + 1 > end)) return false;
+	if (flag & same_flag)
+	  v += *p++;
+	else
+	  v -= *p++;
+      }
+      else
+      {
+	if (!(flag & same_flag))
+	{
+	  if (unlikely (p + HBINT16::static_size > end)) return false;
+	  v += *(const HBINT16 *) p;
+	  p += HBINT16::static_size;
+	}
+      }
+      points_.arrayZ[i].*m = v;
+    }
+    return true;
+  }
+
+  bool get_contour_points (contour_point_vector_t &points_ /* OUT */,
+			   bool phantom_only = false) const
+  {
+    const HBUINT16 *endPtsOfContours = &StructAfter<HBUINT16> (header);
+    int num_contours = header.numberOfContours;
+    assert (num_contours);
+    /* One extra item at the end, for the instruction-count below. */
+    if (unlikely (!bytes.check_range (&endPtsOfContours[num_contours]))) return false;
+    unsigned int num_points = endPtsOfContours[num_contours - 1] + 1;
+
+    points_.alloc (num_points + 4); // Allocate for phantom points, to avoid a possible copy
+    if (!points_.resize (num_points)) return false;
+    if (phantom_only) return true;
+
+    for (int i = 0; i < num_contours; i++)
+      points_[endPtsOfContours[i]].is_end_point = true;
+
+    /* Skip instructions */
+    const HBUINT8 *p = &StructAtOffset<HBUINT8> (&endPtsOfContours[num_contours + 1],
+						 endPtsOfContours[num_contours]);
+
+    if (unlikely ((const char *) p < bytes.arrayZ)) return false; /* Unlikely overflow */
+    const HBUINT8 *end = (const HBUINT8 *) (bytes.arrayZ + bytes.length);
+    if (unlikely (p >= end)) return false;
+
+    /* Read x & y coordinates */
+    return read_flags (p, points_, end)
+        && read_points (p, points_, end, &contour_point_t::x,
+			FLAG_X_SHORT, FLAG_X_SAME)
+	&& read_points (p, points_, end, &contour_point_t::y,
+			FLAG_Y_SHORT, FLAG_Y_SAME);
+  }
+};
+
+
+} /* namespace glyf_impl */
+} /* namespace OT */
+
+
+#endif /* OT_GLYF_SIMPLEGLYPH_HH */