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

third_party/harfbuzz-ng/src/hb-ot-layout-common-private.hh

+/*
+ * Copyright (C) 2007,2008,2009  Red Hat, Inc.
+ * 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.
+ *
+ * Red Hat Author(s): Behdad Esfahbod
+ * Google Author(s): Behdad Esfahbod
+ */
+
+#ifndef HB_OT_LAYOUT_COMMON_PRIVATE_HH
+#define HB_OT_LAYOUT_COMMON_PRIVATE_HH
+
+#include "hb-ot-layout-private.hh"
+
+#include "hb-open-type-private.hh"
+
+
+#define NO_CONTEXT              ((unsigned int) 0x110000)
+#define NOT_COVERED             ((unsigned int) 0x110000)
+#define MAX_NESTING_LEVEL       8
+
+HB_BEGIN_DECLS
+HB_END_DECLS
+
+
+/*
+ *
+ * OpenType Layout Common Table Formats
+ *
+ */
+
+
+/*
+ * Script, ScriptList, LangSys, Feature, FeatureList, Lookup, LookupList
+ */
+
+template <typename Type>
+struct Record
+{
+  inline int cmp (hb_tag_t a) const {
+    return tag.cmp (a);
+  }
+
+  inline bool sanitize (hb_sanitize_context_t *c, void *base) {
+    TRACE_SANITIZE ();
+    return c->check_struct (this)
+        && offset.sanitize (c, base);
+  }
+
+  Tag           tag;            /* 4-byte Tag identifier */
+  OffsetTo<Type>
+                offset;         /* Offset from beginning of object holding
+                                 * the Record */
+  public:
+  DEFINE_SIZE_STATIC (6);
+};
+
+template <typename Type>
+struct RecordArrayOf : SortedArrayOf<Record<Type> > {
+  inline const Tag& get_tag (unsigned int i) const
+  {
+    /* We cheat slightly and don't define separate Null objects
+     * for Record types.  Instead, we return the correct Null(Tag)
+     * here. */
+    if (unlikely (i >= this->len)) return Null(Tag);
+    return (*this)[i].tag;
+  }
+  inline unsigned int get_tags (unsigned int start_offset,
+                                unsigned int *record_count /* IN/OUT */,
+                                hb_tag_t     *record_tags /* OUT */) const
+  {
+    if (record_count) {
+      const Record<Type> *array = this->sub_array (start_offset, record_count);
+      unsigned int count = *record_count;
+      for (unsigned int i = 0; i < count; i++)
+        record_tags[i] = array[i].tag;
+    }
+    return this->len;
+  }
+  inline bool find_index (hb_tag_t tag, unsigned int *index) const
+  {
+    int i = this->search (tag);
+    if (i != -1) {
+        if (index) *index = i;
+        return true;
+    } else {
+      if (index) *index = Index::NOT_FOUND_INDEX;
+      return false;
+    }
+  }
+};
+
+template <typename Type>
+struct RecordListOf : RecordArrayOf<Type>
+{
+  inline const Type& operator [] (unsigned int i) const
+  { return this+RecordArrayOf<Type>::operator [](i).offset; }
+
+  inline bool sanitize (hb_sanitize_context_t *c) {
+    TRACE_SANITIZE ();
+    return RecordArrayOf<Type>::sanitize (c, this);
+  }
+};
+
+
+struct RangeRecord
+{
+  inline int cmp (hb_codepoint_t g) const {
+    hb_codepoint_t a = start, b = end;
+    return g < a ? -1 : g <= b ? 0 : +1 ;
+  }
+
+  inline bool sanitize (hb_sanitize_context_t *c) {
+    TRACE_SANITIZE ();
+    return c->check_struct (this);
+  }
+
+  GlyphID       start;          /* First GlyphID in the range */
+  GlyphID       end;            /* Last GlyphID in the range */
+  USHORT        value;          /* Value */
+  public:
+  DEFINE_SIZE_STATIC (6);
+};
+DEFINE_NULL_DATA (RangeRecord, "\000\001");
+
+
+struct IndexArray : ArrayOf<Index>
+{
+  inline unsigned int get_indexes (unsigned int start_offset,
+                                   unsigned int *_count /* IN/OUT */,
+                                   unsigned int *_indexes /* OUT */) const
+  {
+    if (_count) {
+      const USHORT *array = this->sub_array (start_offset, _count);
+      unsigned int count = *_count;
+      for (unsigned int i = 0; i < count; i++)
+        _indexes[i] = array[i];
+    }
+    return this->len;
+  }
+};
+
+
+struct Script;
+struct LangSys;
+struct Feature;
+
+
+struct LangSys
+{
+  inline unsigned int get_feature_count (void) const
+  { return featureIndex.len; }
+  inline hb_tag_t get_feature_index (unsigned int i) const
+  { return featureIndex[i]; }
+  inline unsigned int get_feature_indexes (unsigned int start_offset,
+                                           unsigned int *feature_count /* IN/OUT */,
+                                           unsigned int *feature_indexes /* OUT */) const
+  { return featureIndex.get_indexes (start_offset, feature_count, feature_indexes); }
+
+  inline bool has_required_feature (void) const { return reqFeatureIndex != 0xffff; }
+  inline unsigned int get_required_feature_index (void) const
+  {
+    if (reqFeatureIndex == 0xffff)
+      return Index::NOT_FOUND_INDEX;
+   return reqFeatureIndex;;
+  }
+
+  inline bool sanitize (hb_sanitize_context_t *c) {
+    TRACE_SANITIZE ();
+    return c->check_struct (this)
+        && featureIndex.sanitize (c);
+  }
+
+  Offset        lookupOrder;    /* = Null (reserved for an offset to a
+                                 * reordering table) */
+  USHORT        reqFeatureIndex;/* Index of a feature required for this
+                                 * language system--if no required features
+                                 * = 0xFFFF */
+  IndexArray    featureIndex;   /* Array of indices into the FeatureList */
+  public:
+  DEFINE_SIZE_ARRAY (6, featureIndex);
+};
+DEFINE_NULL_DATA (LangSys, "\0\0\xFF\xFF");
+
+
+struct Script
+{
+  inline unsigned int get_lang_sys_count (void) const
+  { return langSys.len; }
+  inline const Tag& get_lang_sys_tag (unsigned int i) const
+  { return langSys.get_tag (i); }
+  inline unsigned int get_lang_sys_tags (unsigned int start_offset,
+                                         unsigned int *lang_sys_count /* IN/OUT */,
+                                         hb_tag_t     *lang_sys_tags /* OUT */) const
+  { return langSys.get_tags (start_offset, lang_sys_count, lang_sys_tags); }
+  inline const LangSys& get_lang_sys (unsigned int i) const
+  {
+    if (i == Index::NOT_FOUND_INDEX) return get_default_lang_sys ();
+    return this+langSys[i].offset;
+  }
+  inline bool find_lang_sys_index (hb_tag_t tag, unsigned int *index) const
+  { return langSys.find_index (tag, index); }
+
+  inline bool has_default_lang_sys (void) const { return defaultLangSys != 0; }
+  inline const LangSys& get_default_lang_sys (void) const { return this+defaultLangSys; }
+
+  inline bool sanitize (hb_sanitize_context_t *c) {
+    TRACE_SANITIZE ();
+    return defaultLangSys.sanitize (c, this)
+        && langSys.sanitize (c, this);
+  }
+
+  private:
+  OffsetTo<LangSys>
+                defaultLangSys; /* Offset to DefaultLangSys table--from
+                                 * beginning of Script table--may be Null */
+  RecordArrayOf<LangSys>
+                langSys;        /* Array of LangSysRecords--listed
+                                 * alphabetically by LangSysTag */
+  public:
+  DEFINE_SIZE_ARRAY (4, langSys);
+};
+
+typedef RecordListOf<Script> ScriptList;
+
+
+struct Feature
+{
+  inline unsigned int get_lookup_count (void) const
+  { return lookupIndex.len; }
+  inline hb_tag_t get_lookup_index (unsigned int i) const
+  { return lookupIndex[i]; }
+  inline unsigned int get_lookup_indexes (unsigned int start_index,
+                                          unsigned int *lookup_count /* IN/OUT */,
+                                          unsigned int *lookup_tags /* OUT */) const
+  { return lookupIndex.get_indexes (start_index, lookup_count, lookup_tags); }
+
+  inline bool sanitize (hb_sanitize_context_t *c) {
+    TRACE_SANITIZE ();
+    return c->check_struct (this)
+        && lookupIndex.sanitize (c);
+  }
+
+  Offset        featureParams;  /* Offset to Feature Parameters table (if one
+                                 * has been defined for the feature), relative
+                                 * to the beginning of the Feature Table; = Null
+                                 * if not required */
+  IndexArray     lookupIndex;   /* Array of LookupList indices */
+  public:
+  DEFINE_SIZE_ARRAY (4, lookupIndex);
+};
+
+typedef RecordListOf<Feature> FeatureList;
+
+
+struct LookupFlag : USHORT
+{
+  enum {
+    RightToLeft         = 0x0001u,
+    IgnoreBaseGlyphs    = 0x0002u,
+    IgnoreLigatures     = 0x0004u,
+    IgnoreMarks         = 0x0008u,
+    IgnoreFlags         = 0x000Eu,
+    UseMarkFilteringSet = 0x0010u,
+    Reserved            = 0x00E0u,
+    MarkAttachmentType  = 0xFF00u
+  };
+  public:
+  DEFINE_SIZE_STATIC (2);
+};
+
+struct Lookup
+{
+  inline unsigned int get_subtable_count (void) const { return subTable.len; }
+
+  inline unsigned int get_type (void) const { return lookupType; }
+
+  /* lookup_props is a 32-bit integer where the lower 16-bit is LookupFlag and
+   * higher 16-bit is mark-filtering-set if the lookup uses one.
+   * Not to be confused with glyph_props which is very similar. */
+  inline uint32_t get_props (void) const
+  {
+    unsigned int flag = lookupFlag;
+    if (unlikely (flag & LookupFlag::UseMarkFilteringSet))
+    {
+      const USHORT &markFilteringSet = StructAfter<USHORT> (subTable);
+      flag += (markFilteringSet << 16);
+    }
+    return flag;
+  }
+
+  inline bool sanitize (hb_sanitize_context_t *c) {
+    TRACE_SANITIZE ();
+    /* Real sanitize of the subtables is done by GSUB/GPOS/... */
+    if (!(c->check_struct (this)
+       && subTable.sanitize (c))) return false;
+    if (unlikely (lookupFlag & LookupFlag::UseMarkFilteringSet))
+    {
+      USHORT &markFilteringSet = StructAfter<USHORT> (subTable);
+      if (!markFilteringSet.sanitize (c)) return false;
+    }
+    return true;
+  }
+
+  USHORT        lookupType;             /* Different enumerations for GSUB and GPOS */
+  USHORT        lookupFlag;             /* Lookup qualifiers */
+  ArrayOf<Offset>
+                subTable;               /* Array of SubTables */
+  USHORT        markFilteringSetX[VAR]; /* Index (base 0) into GDEF mark glyph sets
+                                         * structure. This field is only present if bit
+                                         * UseMarkFilteringSet of lookup flags is set. */
+  public:
+  DEFINE_SIZE_ARRAY2 (6, subTable, markFilteringSetX);
+};
+
+typedef OffsetListOf<Lookup> LookupList;
+
+
+/*
+ * Coverage Table
+ */
+
+struct CoverageFormat1
+{
+  friend struct Coverage;
+
+  private:
+  inline unsigned int get_coverage (hb_codepoint_t glyph_id) const
+  {
+    int i = glyphArray.search (glyph_id);
+    if (i != -1)
+        return i;
+    return NOT_COVERED;
+  }
+
+  inline bool sanitize (hb_sanitize_context_t *c) {
+    TRACE_SANITIZE ();
+    return glyphArray.sanitize (c);
+  }
+
+  private:
+  USHORT        coverageFormat; /* Format identifier--format = 1 */
+  SortedArrayOf<GlyphID>
+                glyphArray;     /* Array of GlyphIDs--in numerical order */
+  public:
+  DEFINE_SIZE_ARRAY (4, glyphArray);
+};
+
+struct CoverageFormat2
+{
+  friend struct Coverage;
+
+  private:
+  inline unsigned int get_coverage (hb_codepoint_t glyph_id) const
+  {
+    int i = rangeRecord.search (glyph_id);
+    if (i != -1) {
+      const RangeRecord &range = rangeRecord[i];
+      return (unsigned int) range.value + (glyph_id - range.start);
+    }
+    return NOT_COVERED;
+  }
+
+  inline bool sanitize (hb_sanitize_context_t *c) {
+    TRACE_SANITIZE ();
+    return rangeRecord.sanitize (c);
+  }
+
+  private:
+  USHORT        coverageFormat; /* Format identifier--format = 2 */
+  SortedArrayOf<RangeRecord>
+                rangeRecord;    /* Array of glyph ranges--ordered by
+                                 * Start GlyphID. rangeCount entries
+                                 * long */
+  public:
+  DEFINE_SIZE_ARRAY (4, rangeRecord);
+};
+
+struct Coverage
+{
+  inline unsigned int operator () (hb_codepoint_t glyph_id) const { return get_coverage (glyph_id); }
+
+  inline unsigned int get_coverage (hb_codepoint_t glyph_id) const
+  {
+    switch (u.format) {
+    case 1: return u.format1.get_coverage(glyph_id);
+    case 2: return u.format2.get_coverage(glyph_id);
+    default:return NOT_COVERED;
+    }
+  }
+
+  inline bool sanitize (hb_sanitize_context_t *c) {
+    TRACE_SANITIZE ();
+    if (!u.format.sanitize (c)) return false;
+    switch (u.format) {
+    case 1: return u.format1.sanitize (c);
+    case 2: return u.format2.sanitize (c);
+    default:return true;
+    }
+  }
+
+  private:
+  union {
+  USHORT                format;         /* Format identifier */
+  CoverageFormat1       format1;
+  CoverageFormat2       format2;
+  } u;
+  public:
+  DEFINE_SIZE_UNION (2, format);
+};
+
+
+/*
+ * Class Definition Table
+ */
+
+struct ClassDefFormat1
+{
+  friend struct ClassDef;
+
+  private:
+  inline unsigned int get_class (hb_codepoint_t glyph_id) const
+  {
+    if ((unsigned int) (glyph_id - startGlyph) < classValue.len)
+      return classValue[glyph_id - startGlyph];
+    return 0;
+  }
+
+  inline bool sanitize (hb_sanitize_context_t *c) {
+    TRACE_SANITIZE ();
+    return c->check_struct (this)
+        && classValue.sanitize (c);
+  }
+
+  USHORT        classFormat;            /* Format identifier--format = 1 */
+  GlyphID       startGlyph;             /* First GlyphID of the classValueArray */
+  ArrayOf<USHORT>
+                classValue;             /* Array of Class Values--one per GlyphID */
+  public:
+  DEFINE_SIZE_ARRAY (6, classValue);
+};
+
+struct ClassDefFormat2
+{
+  friend struct ClassDef;
+
+  private:
+  inline unsigned int get_class (hb_codepoint_t glyph_id) const
+  {
+    int i = rangeRecord.search (glyph_id);
+    if (i != -1)
+      return rangeRecord[i].value;
+    return 0;
+  }
+
+  inline bool sanitize (hb_sanitize_context_t *c) {
+    TRACE_SANITIZE ();
+    return rangeRecord.sanitize (c);
+  }
+
+  USHORT        classFormat;    /* Format identifier--format = 2 */
+  SortedArrayOf<RangeRecord>
+                rangeRecord;    /* Array of glyph ranges--ordered by
+                                 * Start GlyphID */
+  public:
+  DEFINE_SIZE_ARRAY (4, rangeRecord);
+};
+
+struct ClassDef
+{
+  inline unsigned int operator () (hb_codepoint_t glyph_id) const { return get_class (glyph_id); }
+
+  inline unsigned int get_class (hb_codepoint_t glyph_id) const
+  {
+    switch (u.format) {
+    case 1: return u.format1.get_class(glyph_id);
+    case 2: return u.format2.get_class(glyph_id);
+    default:return 0;
+    }
+  }
+
+  inline bool sanitize (hb_sanitize_context_t *c) {
+    TRACE_SANITIZE ();
+    if (!u.format.sanitize (c)) return false;
+    switch (u.format) {
+    case 1: return u.format1.sanitize (c);
+    case 2: return u.format2.sanitize (c);
+    default:return true;
+    }
+  }
+
+  private:
+  union {
+  USHORT                format;         /* Format identifier */
+  ClassDefFormat1       format1;
+  ClassDefFormat2       format2;
+  } u;
+  public:
+  DEFINE_SIZE_UNION (2, format);
+};
+
+
+/*
+ * Device Tables
+ */
+
+struct Device
+{
+
+  inline hb_position_t get_x_delta (hb_ot_layout_context_t *c) const
+  { return get_delta (c->font->x_ppem, c->font->x_scale); }
+
+  inline hb_position_t get_y_delta (hb_ot_layout_context_t *c) const
+  { return get_delta (c->font->y_ppem, c->font->y_scale); }
+
+  inline int get_delta (unsigned int ppem, unsigned int scale) const
+  {
+    if (!ppem) return 0;
+
+    int pixels = get_delta_pixels (ppem);
+
+    if (!pixels) return 0;
+
+    /* pixels is at most in the -8..7 range.  So 64-bit arithmetic is
+     * not really necessary here.  A simple cast to int may just work
+     * as well.  But since this code is not reached that often and
+     * for the sake of correctness, we do a 64bit operation. */
+    return pixels * (int64_t) scale / ppem;
+  }
+
+
+  inline int get_delta_pixels (unsigned int ppem_size) const
+  {
+    unsigned int f = deltaFormat;
+    if (unlikely (f < 1 || f > 3))
+      return 0;
+
+    if (ppem_size < startSize || ppem_size > endSize)
+      return 0;
+
+    unsigned int s = ppem_size - startSize;
+
+    unsigned int byte = deltaValue[s >> (4 - f)];
+    unsigned int bits = (byte >> (16 - (((s & ((1 << (4 - f)) - 1)) + 1) << f)));
+    unsigned int mask = (0xFFFF >> (16 - (1 << f)));
+
+    int delta = bits & mask;
+
+    if ((unsigned int) delta >= ((mask + 1) >> 1))
+      delta -= mask + 1;
+
+    return delta;
+  }
+
+  inline unsigned int get_size (void) const
+  {
+    unsigned int f = deltaFormat;
+    if (unlikely (f < 1 || f > 3 || startSize > endSize)) return 3 * USHORT::static_size;
+    return USHORT::static_size * (4 + ((endSize - startSize) >> (4 - f)));
+  }
+
+  inline bool sanitize (hb_sanitize_context_t *c) {
+    TRACE_SANITIZE ();
+    return c->check_struct (this)
+        && c->check_range (this, this->get_size ());
+  }
+
+  private:
+  USHORT        startSize;              /* Smallest size to correct--in ppem */
+  USHORT        endSize;                /* Largest size to correct--in ppem */
+  USHORT        deltaFormat;            /* Format of DeltaValue array data: 1, 2, or 3
+                                         * 1    Signed 2-bit value, 8 values per uint16
+                                         * 2    Signed 4-bit value, 4 values per uint16
+                                         * 3    Signed 8-bit value, 2 values per uint16
+                                         */
+  USHORT        deltaValue[VAR];        /* Array of compressed data */
+  public:
+  DEFINE_SIZE_ARRAY (6, deltaValue);
+};
+
+
+HB_BEGIN_DECLS
+HB_END_DECLS
+
+#endif /* HB_OT_LAYOUT_COMMON_PRIVATE_HH */