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-rw-r--r--Build/source/libs/harfbuzz/harfbuzz-src/src/hb-machinery.hh618
1 files changed, 4 insertions, 614 deletions
diff --git a/Build/source/libs/harfbuzz/harfbuzz-src/src/hb-machinery.hh b/Build/source/libs/harfbuzz/harfbuzz-src/src/hb-machinery.hh
index ffa423d2fe4..5a2087e4aa9 100644
--- a/Build/source/libs/harfbuzz/harfbuzz-src/src/hb-machinery.hh
+++ b/Build/source/libs/harfbuzz/harfbuzz-src/src/hb-machinery.hh
@@ -32,8 +32,9 @@
#include "hb.hh"
#include "hb-blob.hh"
-#include "hb-array.hh"
-#include "hb-vector.hh"
+#include "hb-dispatch.hh"
+#include "hb-sanitize.hh"
+#include "hb-serialize.hh"
/*
@@ -143,617 +144,6 @@ static inline Type& StructAfter(TObject &X)
DEFINE_SIZE_ARRAY(size, array)
-/*
- * Dispatch
- */
-
-template <typename Context, typename Return, unsigned int MaxDebugDepth>
-struct hb_dispatch_context_t
-{
- static constexpr unsigned max_debug_depth = MaxDebugDepth;
- typedef Return return_t;
- template <typename T, typename F>
- bool may_dispatch (const T *obj HB_UNUSED, const F *format HB_UNUSED) { return true; }
- static return_t no_dispatch_return_value () { return Context::default_return_value (); }
- static bool stop_sublookup_iteration (const return_t r HB_UNUSED) { return false; }
-};
-
-
-/*
- * Sanitize
- *
- *
- * === Introduction ===
- *
- * The sanitize machinery is at the core of our zero-cost font loading. We
- * mmap() font file into memory and create a blob out of it. Font subtables
- * are returned as a readonly sub-blob of the main font blob. These table
- * blobs are then sanitized before use, to ensure invalid memory access does
- * not happen. The toplevel sanitize API use is like, eg. to load the 'head'
- * table:
- *
- * hb_blob_t *head_blob = hb_sanitize_context_t ().reference_table<OT::head> (face);
- *
- * The blob then can be converted to a head table struct with:
- *
- * const head *head_table = head_blob->as<head> ();
- *
- * What the reference_table does is, to call hb_face_reference_table() to load
- * the table blob, sanitize it and return either the sanitized blob, or empty
- * blob if sanitization failed. The blob->as() function returns the null
- * object of its template type argument if the blob is empty. Otherwise, it
- * just casts the blob contents to the desired type.
- *
- * Sanitizing a blob of data with a type T works as follows (with minor
- * simplification):
- *
- * - Cast blob content to T*, call sanitize() method of it,
- * - If sanitize succeeded, return blob.
- * - Otherwise, if blob is not writable, try making it writable,
- * or copy if cannot be made writable in-place,
- * - Call sanitize() again. Return blob if sanitize succeeded.
- * - Return empty blob otherwise.
- *
- *
- * === The sanitize() contract ===
- *
- * The sanitize() method of each object type shall return true if it's safe to
- * call other methods of the object, and false otherwise.
- *
- * Note that what sanitize() checks for might align with what the specification
- * describes as valid table data, but does not have to be. In particular, we
- * do NOT want to be pedantic and concern ourselves with validity checks that
- * are irrelevant to our use of the table. On the contrary, we want to be
- * lenient with error handling and accept invalid data to the extent that it
- * does not impose extra burden on us.
- *
- * Based on the sanitize contract, one can see that what we check for depends
- * on how we use the data in other table methods. Ie. if other table methods
- * assume that offsets do NOT point out of the table data block, then that's
- * something sanitize() must check for (GSUB/GPOS/GDEF/etc work this way). On
- * the other hand, if other methods do such checks themselves, then sanitize()
- * does not have to bother with them (glyf/local work this way). The choice
- * depends on the table structure and sanitize() performance. For example, to
- * check glyf/loca offsets in sanitize() would cost O(num-glyphs). We try hard
- * to avoid such costs during font loading. By postponing such checks to the
- * actual glyph loading, we reduce the sanitize cost to O(1) and total runtime
- * cost to O(used-glyphs). As such, this is preferred.
- *
- * The same argument can be made re GSUB/GPOS/GDEF, but there, the table
- * structure is so complicated that by checking all offsets at sanitize() time,
- * we make the code much simpler in other methods, as offsets and referenced
- * objects do not need to be validated at each use site.
- */
-
-/* This limits sanitizing time on really broken fonts. */
-#ifndef HB_SANITIZE_MAX_EDITS
-#define HB_SANITIZE_MAX_EDITS 32
-#endif
-#ifndef HB_SANITIZE_MAX_OPS_FACTOR
-#define HB_SANITIZE_MAX_OPS_FACTOR 8
-#endif
-#ifndef HB_SANITIZE_MAX_OPS_MIN
-#define HB_SANITIZE_MAX_OPS_MIN 16384
-#endif
-#ifndef HB_SANITIZE_MAX_OPS_MAX
-#define HB_SANITIZE_MAX_OPS_MAX 0x3FFFFFFF
-#endif
-
-struct hb_sanitize_context_t :
- hb_dispatch_context_t<hb_sanitize_context_t, bool, HB_DEBUG_SANITIZE>
-{
- hb_sanitize_context_t () :
- debug_depth (0),
- start (nullptr), end (nullptr),
- max_ops (0),
- writable (false), edit_count (0),
- blob (nullptr),
- num_glyphs (65536),
- num_glyphs_set (false) {}
-
- const char *get_name () { return "SANITIZE"; }
- template <typename T, typename F>
- bool may_dispatch (const T *obj HB_UNUSED, const F *format)
- { return format->sanitize (this); }
- template <typename T>
- return_t dispatch (const T &obj) { return obj.sanitize (this); }
- static return_t default_return_value () { return true; }
- static return_t no_dispatch_return_value () { return false; }
- bool stop_sublookup_iteration (const return_t r) const { return !r; }
-
- void init (hb_blob_t *b)
- {
- this->blob = hb_blob_reference (b);
- this->writable = false;
- }
-
- void set_num_glyphs (unsigned int num_glyphs_)
- {
- num_glyphs = num_glyphs_;
- num_glyphs_set = true;
- }
- unsigned int get_num_glyphs () { return num_glyphs; }
-
- void set_max_ops (int max_ops_) { max_ops = max_ops_; }
-
- template <typename T>
- void set_object (const T *obj)
- {
- reset_object ();
-
- if (!obj) return;
-
- const char *obj_start = (const char *) obj;
- if (unlikely (obj_start < this->start || this->end <= obj_start))
- this->start = this->end = nullptr;
- else
- {
- this->start = obj_start;
- this->end = obj_start + MIN<uintptr_t> (this->end - obj_start, obj->get_size ());
- }
- }
-
- void reset_object ()
- {
- this->start = this->blob->data;
- this->end = this->start + this->blob->length;
- assert (this->start <= this->end); /* Must not overflow. */
- }
-
- void start_processing ()
- {
- reset_object ();
- this->max_ops = MAX ((unsigned int) (this->end - this->start) * HB_SANITIZE_MAX_OPS_FACTOR,
- (unsigned) HB_SANITIZE_MAX_OPS_MIN);
- this->edit_count = 0;
- this->debug_depth = 0;
-
- DEBUG_MSG_LEVEL (SANITIZE, start, 0, +1,
- "start [%p..%p] (%lu bytes)",
- this->start, this->end,
- (unsigned long) (this->end - this->start));
- }
-
- void end_processing ()
- {
- DEBUG_MSG_LEVEL (SANITIZE, this->start, 0, -1,
- "end [%p..%p] %u edit requests",
- this->start, this->end, this->edit_count);
-
- hb_blob_destroy (this->blob);
- this->blob = nullptr;
- this->start = this->end = nullptr;
- }
-
- bool check_range (const void *base,
- unsigned int len) const
- {
- const char *p = (const char *) base;
- bool ok = !len ||
- (this->start <= p &&
- p <= this->end &&
- (unsigned int) (this->end - p) >= len &&
- this->max_ops-- > 0);
-
- DEBUG_MSG_LEVEL (SANITIZE, p, this->debug_depth+1, 0,
- "check_range [%p..%p]"
- " (%d bytes) in [%p..%p] -> %s",
- p, p + len, len,
- this->start, this->end,
- ok ? "OK" : "OUT-OF-RANGE");
-
- return likely (ok);
- }
-
- template <typename T>
- bool check_range (const T *base,
- unsigned int a,
- unsigned int b) const
- {
- return !hb_unsigned_mul_overflows (a, b) &&
- this->check_range (base, a * b);
- }
-
- template <typename T>
- bool check_range (const T *base,
- unsigned int a,
- unsigned int b,
- unsigned int c) const
- {
- return !hb_unsigned_mul_overflows (a, b) &&
- this->check_range (base, a * b, c);
- }
-
- template <typename T>
- bool check_array (const T *base, unsigned int len) const
- {
- return this->check_range (base, len, hb_static_size (T));
- }
-
- template <typename T>
- bool check_array (const T *base,
- unsigned int a,
- unsigned int b) const
- {
- return this->check_range (base, a, b, hb_static_size (T));
- }
-
- template <typename Type>
- bool check_struct (const Type *obj) const
- { return likely (this->check_range (obj, obj->min_size)); }
-
- bool may_edit (const void *base, unsigned int len)
- {
- if (this->edit_count >= HB_SANITIZE_MAX_EDITS)
- return false;
-
- const char *p = (const char *) base;
- this->edit_count++;
-
- DEBUG_MSG_LEVEL (SANITIZE, p, this->debug_depth+1, 0,
- "may_edit(%u) [%p..%p] (%d bytes) in [%p..%p] -> %s",
- this->edit_count,
- p, p + len, len,
- this->start, this->end,
- this->writable ? "GRANTED" : "DENIED");
-
- return this->writable;
- }
-
- template <typename Type, typename ValueType>
- bool try_set (const Type *obj, const ValueType &v)
- {
- if (this->may_edit (obj, hb_static_size (Type)))
- {
- hb_assign (* const_cast<Type *> (obj), v);
- return true;
- }
- return false;
- }
-
- template <typename Type>
- hb_blob_t *sanitize_blob (hb_blob_t *blob)
- {
- bool sane;
-
- init (blob);
-
- retry:
- DEBUG_MSG_FUNC (SANITIZE, start, "start");
-
- start_processing ();
-
- if (unlikely (!start))
- {
- end_processing ();
- return blob;
- }
-
- Type *t = CastP<Type> (const_cast<char *> (start));
-
- sane = t->sanitize (this);
- if (sane)
- {
- if (edit_count)
- {
- DEBUG_MSG_FUNC (SANITIZE, start, "passed first round with %d edits; going for second round", edit_count);
-
- /* sanitize again to ensure no toe-stepping */
- edit_count = 0;
- sane = t->sanitize (this);
- if (edit_count) {
- DEBUG_MSG_FUNC (SANITIZE, start, "requested %d edits in second round; FAILLING", edit_count);
- sane = false;
- }
- }
- }
- else
- {
- if (edit_count && !writable) {
- start = hb_blob_get_data_writable (blob, nullptr);
- end = start + blob->length;
-
- if (start)
- {
- writable = true;
- /* ok, we made it writable by relocating. try again */
- DEBUG_MSG_FUNC (SANITIZE, start, "retry");
- goto retry;
- }
- }
- }
-
- end_processing ();
-
- DEBUG_MSG_FUNC (SANITIZE, start, sane ? "PASSED" : "FAILED");
- if (sane)
- {
- hb_blob_make_immutable (blob);
- return blob;
- }
- else
- {
- hb_blob_destroy (blob);
- return hb_blob_get_empty ();
- }
- }
-
- template <typename Type>
- hb_blob_t *reference_table (const hb_face_t *face, hb_tag_t tableTag = Type::tableTag)
- {
- if (!num_glyphs_set)
- set_num_glyphs (hb_face_get_glyph_count (face));
- return sanitize_blob<Type> (hb_face_reference_table (face, tableTag));
- }
-
- mutable unsigned int debug_depth;
- const char *start, *end;
- mutable int max_ops;
- private:
- bool writable;
- unsigned int edit_count;
- hb_blob_t *blob;
- unsigned int num_glyphs;
- bool num_glyphs_set;
-};
-
-struct hb_sanitize_with_object_t
-{
- template <typename T>
- hb_sanitize_with_object_t (hb_sanitize_context_t *c,
- const T& obj) : c (c)
- { c->set_object (obj); }
- ~hb_sanitize_with_object_t ()
- { c->reset_object (); }
-
- private:
- hb_sanitize_context_t *c;
-};
-
-
-/*
- * Serialize
- */
-
-struct hb_serialize_context_t
-{
- hb_serialize_context_t (void *start_, unsigned int size)
- {
- this->start = (char *) start_;
- this->end = this->start + size;
- reset ();
- }
-
- bool in_error () const { return !this->successful; }
-
- void reset ()
- {
- this->successful = true;
- this->head = this->start;
- this->debug_depth = 0;
- }
-
- bool propagate_error (bool e)
- { return this->successful = this->successful && e; }
- template <typename T> bool propagate_error (const T &obj)
- { return this->successful = this->successful && !obj.in_error (); }
- template <typename T> bool propagate_error (const T *obj)
- { return this->successful = this->successful && !obj->in_error (); }
- template <typename T1, typename T2> bool propagate_error (T1 &o1, T2 &o2)
- { return propagate_error (o1) && propagate_error (o2); }
- template <typename T1, typename T2> bool propagate_error (T1 *o1, T2 *o2)
- { return propagate_error (o1) && propagate_error (o2); }
- template <typename T1, typename T2, typename T3>
- bool propagate_error (T1 &o1, T2 &o2, T3 &o3)
- { return propagate_error (o1) && propagate_error (o2, o3); }
- template <typename T1, typename T2, typename T3>
- bool propagate_error (T1 *o1, T2 *o2, T3 *o3)
- { return propagate_error (o1) && propagate_error (o2, o3); }
-
- /* To be called around main operation. */
- template <typename Type>
- Type *start_serialize ()
- {
- DEBUG_MSG_LEVEL (SERIALIZE, this->start, 0, +1,
- "start [%p..%p] (%lu bytes)",
- this->start, this->end,
- (unsigned long) (this->end - this->start));
-
- return start_embed<Type> ();
- }
- void end_serialize ()
- {
- DEBUG_MSG_LEVEL (SERIALIZE, this->start, 0, -1,
- "end [%p..%p] serialized %d bytes; %s",
- this->start, this->end,
- (int) (this->head - this->start),
- this->successful ? "successful" : "UNSUCCESSFUL");
- }
-
- unsigned int length () const { return this->head - this->start; }
-
- void align (unsigned int alignment)
- {
- unsigned int l = length () % alignment;
- if (l)
- allocate_size<void> (alignment - l);
- }
-
- template <typename Type>
- Type *start_embed (const Type *_ HB_UNUSED = nullptr) const
- {
- Type *ret = reinterpret_cast<Type *> (this->head);
- return ret;
- }
-
- template <typename Type>
- Type *allocate_size (unsigned int size)
- {
- if (unlikely (!this->successful || this->end - this->head < ptrdiff_t (size))) {
- this->successful = false;
- return nullptr;
- }
- memset (this->head, 0, size);
- char *ret = this->head;
- this->head += size;
- return reinterpret_cast<Type *> (ret);
- }
-
- template <typename Type>
- Type *allocate_min ()
- {
- return this->allocate_size<Type> (Type::min_size);
- }
-
- template <typename Type>
- Type *embed (const Type &obj)
- {
- unsigned int size = obj.get_size ();
- Type *ret = this->allocate_size<Type> (size);
- if (unlikely (!ret)) return nullptr;
- memcpy (ret, &obj, size);
- return ret;
- }
- template <typename Type>
- hb_serialize_context_t &operator << (const Type &obj) { embed (obj); return *this; }
-
- template <typename Type>
- Type *extend_size (Type &obj, unsigned int size)
- {
- assert (this->start <= (char *) &obj);
- assert ((char *) &obj <= this->head);
- assert ((char *) &obj + size >= this->head);
- if (unlikely (!this->allocate_size<Type> (((char *) &obj) + size - this->head))) return nullptr;
- return reinterpret_cast<Type *> (&obj);
- }
-
- template <typename Type>
- Type *extend_min (Type &obj) { return extend_size (obj, obj.min_size); }
-
- template <typename Type>
- Type *extend (Type &obj) { return extend_size (obj, obj.get_size ()); }
-
- /* Output routines. */
- template <typename Type>
- Type *copy () const
- {
- assert (this->successful);
- unsigned int len = this->head - this->start;
- void *p = malloc (len);
- if (p)
- memcpy (p, this->start, len);
- return reinterpret_cast<Type *> (p);
- }
- hb_bytes_t copy_bytes () const
- {
- assert (this->successful);
- unsigned int len = this->head - this->start;
- void *p = malloc (len);
- if (p)
- memcpy (p, this->start, len);
- else
- return hb_bytes_t ();
- return hb_bytes_t ((char *) p, len);
- }
- hb_blob_t *copy_blob () const
- {
- assert (this->successful);
- return hb_blob_create (this->start,
- this->head - this->start,
- HB_MEMORY_MODE_DUPLICATE,
- nullptr, nullptr);
- }
-
- public:
- unsigned int debug_depth;
- char *start, *end, *head;
- bool successful;
-};
-
-
-
-/*
- * Big-endian integers.
- */
-
-template <typename Type, int Bytes> struct BEInt;
-
-template <typename Type>
-struct BEInt<Type, 1>
-{
- public:
- void set (Type V) { v = V; }
- operator Type () const { return v; }
- private: uint8_t v;
-};
-template <typename Type>
-struct BEInt<Type, 2>
-{
- public:
- void set (Type V)
- {
- v[0] = (V >> 8) & 0xFF;
- v[1] = (V ) & 0xFF;
- }
- operator Type () const
- {
-#if ((defined(__GNUC__) && __GNUC__ >= 5) || defined(__clang__)) && \
- defined(__BYTE_ORDER) && \
- (__BYTE_ORDER == __LITTLE_ENDIAN || __BYTE_ORDER == __BIG_ENDIAN)
- /* Spoon-feed the compiler a big-endian integer with alignment 1.
- * https://github.com/harfbuzz/harfbuzz/pull/1398 */
- struct __attribute__((packed)) packed_uint16_t { uint16_t v; };
-#if __BYTE_ORDER == __LITTLE_ENDIAN
- return __builtin_bswap16 (((packed_uint16_t *) this)->v);
-#else /* __BYTE_ORDER == __BIG_ENDIAN */
- return ((packed_uint16_t *) this)->v;
-#endif
-#endif
- return (v[0] << 8)
- + (v[1] );
- }
- private: uint8_t v[2];
-};
-template <typename Type>
-struct BEInt<Type, 3>
-{
- public:
- void set (Type V)
- {
- v[0] = (V >> 16) & 0xFF;
- v[1] = (V >> 8) & 0xFF;
- v[2] = (V ) & 0xFF;
- }
- operator Type () const
- {
- return (v[0] << 16)
- + (v[1] << 8)
- + (v[2] );
- }
- private: uint8_t v[3];
-};
-template <typename Type>
-struct BEInt<Type, 4>
-{
- public:
- typedef Type type;
- void set (Type V)
- {
- v[0] = (V >> 24) & 0xFF;
- v[1] = (V >> 16) & 0xFF;
- v[2] = (V >> 8) & 0xFF;
- v[3] = (V ) & 0xFF;
- }
- operator Type () const
- {
- return (v[0] << 24)
- + (v[1] << 16)
- + (v[2] << 8)
- + (v[3] );
- }
- private: uint8_t v[4];
-};
-
/*
* Lazy loaders.
@@ -816,7 +206,7 @@ struct hb_lazy_loader_t : hb_data_wrapper_t<Data, WheresData>
const Returned * operator -> () const { return get (); }
const Returned & operator * () const { return *get (); }
- explicit_operator bool () const
+ explicit operator bool () const
{ return get_stored () != Funcs::get_null (); }
template <typename C> operator const C * () const { return get (); }