* Serialize
*/
+enum hb_serialize_error_t {
+ HB_SERIALIZE_ERROR_NONE = 0x00000000u,
+ HB_SERIALIZE_ERROR_OTHER = 0x00000001u,
+ HB_SERIALIZE_ERROR_OFFSET_OVERFLOW = 0x00000002u,
+ HB_SERIALIZE_ERROR_OUT_OF_ROOM = 0x00000004u,
+ HB_SERIALIZE_ERROR_INT_OVERFLOW = 0x00000008u,
+ HB_SERIALIZE_ERROR_ARRAY_OVERFLOW = 0x00000010u
+};
+HB_MARK_AS_FLAG_T (hb_serialize_error_t);
+
struct hb_serialize_context_t
{
typedef unsigned objidx_t;
Absolute /* Absolute: from the start of the serialize buffer. */
};
+
+
struct object_t
{
- void fini () { links.fini (); }
+ void fini () {
+ real_links.fini ();
+ virtual_links.fini ();
+ }
bool operator == (const object_t &o) const
{
+ // Virtual links aren't considered for equality since they don't affect the functionality
+ // of the object.
return (tail - head == o.tail - o.head)
- && (links.length == o.links.length)
+ && (real_links.length == o.real_links.length)
&& 0 == hb_memcmp (head, o.head, tail - head)
- && links.as_bytes () == o.links.as_bytes ();
+ && real_links.as_bytes () == o.real_links.as_bytes ();
}
uint32_t hash () const
{
+ // Virtual links aren't considered for equality since they don't affect the functionality
+ // of the object.
return hb_bytes_t (head, tail - head).hash () ^
- links.as_bytes ().hash ();
+ real_links.as_bytes ().hash ();
}
struct link_t
{
- bool is_wide: 1;
+ unsigned width: 3;
bool is_signed: 1;
unsigned whence: 2;
unsigned position: 28;
char *head;
char *tail;
- hb_vector_t<link_t> links;
+ hb_vector_t<link_t> real_links;
+ hb_vector_t<link_t> virtual_links;
object_t *next;
+
+ auto all_links () const HB_AUTO_RETURN
+ (( hb_concat (this->real_links, this->virtual_links) ));
+ auto all_links_writer () HB_AUTO_RETURN
+ (( hb_concat (this->real_links.writer (), this->virtual_links.writer ()) ));
};
struct snapshot_t
char *head;
char *tail;
object_t *current; // Just for sanity check
- unsigned num_links;
+ unsigned num_real_links;
+ unsigned num_virtual_links;
+ hb_serialize_error_t errors;
};
snapshot_t snapshot ()
- { return snapshot_t { head, tail, current, current->links.length }; }
+ { return snapshot_t {
+ head, tail, current, current->real_links.length, current->virtual_links.length, errors }; }
hb_serialize_context_t (void *start_, unsigned int size) :
start ((char *) start_),
object_pool.fini ();
}
- bool in_error () const { return !this->successful; }
+ bool in_error () const { return bool (errors); }
+
+ bool successful () const { return !bool (errors); }
+
+ HB_NODISCARD bool ran_out_of_room () const { return errors & HB_SERIALIZE_ERROR_OUT_OF_ROOM; }
+ HB_NODISCARD bool offset_overflow () const { return errors & HB_SERIALIZE_ERROR_OFFSET_OVERFLOW; }
+ HB_NODISCARD bool only_offset_overflow () const { return errors == HB_SERIALIZE_ERROR_OFFSET_OVERFLOW; }
+ HB_NODISCARD bool only_overflow () const
+ {
+ return errors == HB_SERIALIZE_ERROR_OFFSET_OVERFLOW
+ || errors == HB_SERIALIZE_ERROR_INT_OVERFLOW
+ || errors == HB_SERIALIZE_ERROR_ARRAY_OVERFLOW;
+ }
+
+ void reset (void *start_, unsigned int size)
+ {
+ start = (char*) start_;
+ end = start + size;
+ reset ();
+ current = nullptr;
+ }
void reset ()
{
- this->successful = true;
- this->ran_out_of_room = false;
+ this->errors = HB_SERIALIZE_ERROR_NONE;
this->head = this->start;
this->tail = this->end;
this->debug_depth = 0;
fini ();
this->packed.push (nullptr);
+ this->packed_map.init ();
}
- bool check_success (bool success)
- { return this->successful && (success || (err_other_error (), false)); }
+ bool check_success (bool success,
+ hb_serialize_error_t err_type = HB_SERIALIZE_ERROR_OTHER)
+ {
+ return successful ()
+ && (success || err (err_type));
+ }
template <typename T1, typename T2>
- bool check_equal (T1 &&v1, T2 &&v2)
- { return check_success ((long long) v1 == (long long) v2); }
+ bool check_equal (T1 &&v1, T2 &&v2, hb_serialize_error_t err_type)
+ {
+ if ((long long) v1 != (long long) v2)
+ {
+ return err (err_type);
+ }
+ return true;
+ }
template <typename T1, typename T2>
- bool check_assign (T1 &v1, T2 &&v2)
- { return check_equal (v1 = v2, v2); }
+ bool check_assign (T1 &v1, T2 &&v2, hb_serialize_error_t err_type)
+ { return check_equal (v1 = v2, v2, err_type); }
template <typename T> bool propagate_error (T &&obj)
{ return check_success (!hb_deref (obj).in_error ()); }
template <typename T1, typename... Ts> bool propagate_error (T1 &&o1, Ts&&... os)
- { return propagate_error (hb_forward<T1> (o1)) &&
- propagate_error (hb_forward<Ts> (os)...); }
+ { return propagate_error (std::forward<T1> (o1)) &&
+ propagate_error (std::forward<Ts> (os)...); }
/* To be called around main operation. */
template <typename Type>
"end [%p..%p] serialized %u bytes; %s",
this->start, this->end,
(unsigned) (this->head - this->start),
- this->successful ? "successful" : "UNSUCCESSFUL");
+ successful () ? "successful" : "UNSUCCESSFUL");
propagate_error (packed, packed_map);
if (unlikely (!current)) return;
+ if (unlikely (in_error()))
+ {
+ // Offset overflows that occur before link resolution cannot be handled
+ // by repacking, so set a more general error.
+ if (offset_overflow ()) err (HB_SERIALIZE_ERROR_OTHER);
+ return;
+ }
+
assert (!current->next);
/* Only "pack" if there exist other objects... Otherwise, don't bother.
template <typename Type = void>
Type *push ()
{
+ if (unlikely (in_error ())) return start_embed<Type> ();
+
object_t *obj = object_pool.alloc ();
if (unlikely (!obj))
check_success (false);
{
object_t *obj = current;
if (unlikely (!obj)) return;
+ if (unlikely (in_error())) return;
+
current = current->next;
revert (obj->head, obj->tail);
obj->fini ();
- object_pool.free (obj);
+ object_pool.release (obj);
}
- /* Set share to false when an object is unlikely sharable with others
+ /* Set share to false when an object is unlikely shareable with others
* so not worth an attempt, or a contiguous table is serialized as
* multiple consecutive objects in the reverse order so can't be shared.
*/
{
object_t *obj = current;
if (unlikely (!obj)) return 0;
+ if (unlikely (in_error())) return 0;
+
current = current->next;
obj->tail = head;
obj->next = nullptr;
if (!len)
{
- assert (!obj->links.length);
+ assert (!obj->real_links.length);
+ assert (!obj->virtual_links.length);
return 0;
}
objidx = packed_map.get (obj);
if (objidx)
{
+ merge_virtual_links (obj, objidx);
obj->fini ();
return objidx;
}
packed.push (obj);
- if (unlikely (packed.in_error ()))
+ if (unlikely (!propagate_error (packed)))
+ {
+ /* Obj wasn't successfully added to packed, so clean it up otherwise its
+ * links will be leaked. When we use constructor/destructors properly, we
+ * can remove these. */
+ obj->fini ();
return 0;
+ }
objidx = packed.length - 1;
if (share) packed_map.set (obj, objidx);
+ propagate_error (packed_map);
return objidx;
}
void revert (snapshot_t snap)
{
+ // Overflows that happened after the snapshot will be erased by the revert.
+ if (unlikely (in_error () && !only_overflow ())) return;
assert (snap.current == current);
- current->links.shrink (snap.num_links);
+ current->real_links.shrink (snap.num_real_links);
+ current->virtual_links.shrink (snap.num_virtual_links);
+ errors = snap.errors;
revert (snap.head, snap.tail);
}
+
void revert (char *snap_head,
char *snap_tail)
{
+ if (unlikely (in_error ())) return;
assert (snap_head <= head);
assert (tail <= snap_tail);
head = snap_head;
void discard_stale_objects ()
{
+ if (unlikely (in_error ())) return;
while (packed.length > 1 &&
packed.tail ()->head < tail)
{
assert (packed.tail ()->head == tail);
}
+ // Adds a virtual link from the current object to objidx. A virtual link is not associated with
+ // an actual offset field. They are solely used to enforce ordering constraints between objects.
+ // Adding a virtual link from object a to object b will ensure that object b is always packed after
+ // object a in the final serialized order.
+ //
+ // This is useful in certain situations where there needs to be a specific ordering in the
+ // final serialization. Such as when platform bugs require certain orderings, or to provide
+ // guidance to the repacker for better offset overflow resolution.
+ void add_virtual_link (objidx_t objidx)
+ {
+ if (unlikely (in_error ())) return;
+
+ if (!objidx)
+ return;
+
+ assert (current);
+
+ auto& link = *current->virtual_links.push ();
+ if (current->virtual_links.in_error ())
+ err (HB_SERIALIZE_ERROR_OTHER);
+
+ link.width = 0;
+ link.objidx = objidx;
+ link.is_signed = 0;
+ link.whence = 0;
+ link.position = 0;
+ link.bias = 0;
+ }
+
template <typename T>
void add_link (T &ofs, objidx_t objidx,
whence_t whence = Head,
unsigned bias = 0)
{
- static_assert (sizeof (T) == 2 || sizeof (T) == 4, "");
+ if (unlikely (in_error ())) return;
if (!objidx)
return;
assert (current);
assert (current->head <= (const char *) &ofs);
- auto& link = *current->links.push ();
+ auto& link = *current->real_links.push ();
+ if (current->real_links.in_error ())
+ err (HB_SERIALIZE_ERROR_OTHER);
- link.is_wide = sizeof (T) == 4;
- link.is_signed = hb_is_signed (hb_unwrap_type (T));
+ link.width = sizeof (T);
+ link.objidx = objidx;
+ if (unlikely (!sizeof (T)))
+ {
+ // This link is not associated with an actual offset and exists merely to enforce
+ // an ordering constraint.
+ link.is_signed = 0;
+ link.whence = 0;
+ link.position = 0;
+ link.bias = 0;
+ return;
+ }
+
+ link.is_signed = std::is_signed<hb_unwrap_type (T)>::value;
link.whence = (unsigned) whence;
link.position = (const char *) &ofs - current->head;
link.bias = bias;
- link.objidx = objidx;
}
unsigned to_bias (const void *base) const
{
+ if (unlikely (in_error ())) return 0;
if (!base) return 0;
assert (current);
assert (current->head <= (const char *) base);
assert (packed.length > 1);
for (const object_t* parent : ++hb_iter (packed))
- for (const object_t::link_t &link : parent->links)
+ for (const object_t::link_t &link : parent->real_links)
{
const object_t* child = packed[link.objidx];
- if (unlikely (!child)) { err_other_error(); return; }
+ if (unlikely (!child)) { err (HB_SERIALIZE_ERROR_OTHER); return; }
unsigned offset = 0;
switch ((whence_t) link.whence) {
case Head: offset = child->head - parent->head; break;
offset -= link.bias;
if (link.is_signed)
{
- if (link.is_wide)
+ assert (link.width == 2 || link.width == 4);
+ if (link.width == 4)
assign_offset<int32_t> (parent, link, offset);
else
assign_offset<int16_t> (parent, link, offset);
}
else
{
- if (link.is_wide)
+ assert (link.width == 2 || link.width == 3 || link.width == 4);
+ if (link.width == 4)
assign_offset<uint32_t> (parent, link, offset);
+ else if (link.width == 3)
+ assign_offset<uint32_t, 3> (parent, link, offset);
else
assign_offset<uint16_t> (parent, link, offset);
}
}
}
- unsigned int length () const { return this->head - current->head; }
+ unsigned int length () const
+ {
+ if (unlikely (!current)) return 0;
+ return this->head - current->head;
+ }
void align (unsigned int alignment)
{
{ return reinterpret_cast<Type *> (this->head); }
template <typename Type>
Type *start_embed (const Type &obj) const
- { return start_embed (hb_addressof (obj)); }
+ { return start_embed (std::addressof (obj)); }
- /* Following two functions exist to allow setting breakpoint on. */
- void err_ran_out_of_room () { this->ran_out_of_room = true; }
- void err_other_error () { this->successful = false; }
+ bool err (hb_serialize_error_t err_type)
+ {
+ return !bool ((errors = (errors | err_type)));
+ }
template <typename Type>
- Type *allocate_size (unsigned int size)
+ Type *allocate_size (size_t size)
{
- if (unlikely (!this->successful)) return nullptr;
+ if (unlikely (in_error ())) return nullptr;
- if (this->tail - this->head < ptrdiff_t (size))
+ if (unlikely (size > INT_MAX || this->tail - this->head < ptrdiff_t (size)))
{
- err_ran_out_of_room ();
- this->successful = false;
+ err (HB_SERIALIZE_ERROR_OUT_OF_ROOM);
return nullptr;
}
- memset (this->head, 0, size);
+ hb_memset (this->head, 0, size);
char *ret = this->head;
this->head += size;
return reinterpret_cast<Type *> (ret);
}
template <typename Type>
Type *embed (const Type &obj)
- { return embed (hb_addressof (obj)); }
+ { return embed (std::addressof (obj)); }
template <typename Type, typename ...Ts> auto
_copy (const Type &src, hb_priority<1>, Ts&&... ds) HB_RETURN
- (Type *, src.copy (this, hb_forward<Ts> (ds)...))
+ (Type *, src.copy (this, std::forward<Ts> (ds)...))
template <typename Type> auto
_copy (const Type &src, hb_priority<0>) -> decltype (&(hb_declval<Type> () = src))
* instead of memcpy(). */
template <typename Type, typename ...Ts>
Type *copy (const Type &src, Ts&&... ds)
- { return _copy (src, hb_prioritize, hb_forward<Ts> (ds)...); }
+ { return _copy (src, hb_prioritize, std::forward<Ts> (ds)...); }
template <typename Type, typename ...Ts>
Type *copy (const Type *src, Ts&&... ds)
- { return copy (*src, hb_forward<Ts> (ds)...); }
+ { return copy (*src, std::forward<Ts> (ds)...); }
template<typename Iterator,
hb_requires (hb_is_iterator (Iterator)),
typename ...Ts>
void copy_all (Iterator it, Ts&&... ds)
- { for (decltype (*it) _ : it) copy (_, hb_forward<Ts> (ds)...); }
+ { for (decltype (*it) _ : it) copy (_, std::forward<Ts> (ds)...); }
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)
+ Type *extend_size (Type *obj, size_t size)
{
+ if (unlikely (in_error ())) return nullptr;
+
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;
+ assert ((size_t) (this->head - (char *) obj) <= size);
+ if (unlikely (((char *) obj + size < (char *) obj) ||
+ !this->allocate_size<Type> (((char *) obj) + size - this->head))) return nullptr;
return reinterpret_cast<Type *> (obj);
}
template <typename Type>
- Type *extend_size (Type &obj, unsigned int size)
- { return extend_size (hb_addressof (obj), size); }
+ Type *extend_size (Type &obj, size_t size)
+ { return extend_size (std::addressof (obj), size); }
template <typename Type>
Type *extend_min (Type *obj) { return extend_size (obj, obj->min_size); }
template <typename Type>
- Type *extend_min (Type &obj) { return extend_min (hb_addressof (obj)); }
+ Type *extend_min (Type &obj) { return extend_min (std::addressof (obj)); }
template <typename Type, typename ...Ts>
Type *extend (Type *obj, Ts&&... ds)
- { return extend_size (obj, obj->get_size (hb_forward<Ts> (ds)...)); }
+ { return extend_size (obj, obj->get_size (std::forward<Ts> (ds)...)); }
template <typename Type, typename ...Ts>
Type *extend (Type &obj, Ts&&... ds)
- { return extend (hb_addressof (obj), hb_forward<Ts> (ds)...); }
+ { return extend (std::addressof (obj), std::forward<Ts> (ds)...); }
/* Output routines. */
hb_bytes_t copy_bytes () const
{
- assert (this->successful);
+ assert (successful ());
/* Copy both items from head side and tail side... */
unsigned int len = (this->head - this->start)
+ (this->end - this->tail);
- char *p = (char *) malloc (len);
+ // If len is zero don't hb_malloc as the memory won't get properly
+ // cleaned up later.
+ if (!len) return hb_bytes_t ();
+
+ char *p = (char *) hb_malloc (len);
if (unlikely (!p)) return hb_bytes_t ();
memcpy (p, this->start, this->head - this->start);
hb_bytes_t b = copy_bytes ();
return hb_blob_create (b.arrayZ, b.length,
HB_MEMORY_MODE_WRITABLE,
- (char *) b.arrayZ, free);
+ (char *) b.arrayZ, hb_free);
}
+ const hb_vector_t<object_t *>& object_graph() const
+ { return packed; }
+
private:
- template <typename T>
+ template <typename T, unsigned Size = sizeof (T)>
void assign_offset (const object_t* parent, const object_t::link_t &link, unsigned offset)
{
- auto &off = * ((BEInt<T, sizeof (T)> *) (parent->head + link.position));
+ auto &off = * ((BEInt<T, Size> *) (parent->head + link.position));
assert (0 == off);
- check_assign (off, offset);
+ check_assign (off, offset, HB_SERIALIZE_ERROR_OFFSET_OVERFLOW);
}
public: /* TODO Make private. */
char *start, *head, *tail, *end;
unsigned int debug_depth;
- bool successful;
- bool ran_out_of_room;
+ hb_serialize_error_t errors;
private:
+ void merge_virtual_links (const object_t* from, objidx_t to_idx) {
+ object_t* to = packed[to_idx];
+ for (const auto& l : from->virtual_links) {
+ to->virtual_links.push (l);
+ }
+ }
+
/* Object memory pool. */
hb_pool_t<object_t> object_pool;
hb_vector_t<object_t *> packed;
/* Map view of packed objects. */
- hb_hashmap_t<const object_t *, objidx_t, nullptr, 0> packed_map;
+ hb_hashmap_t<const object_t *, objidx_t,
+ const object_t *, objidx_t,
+ nullptr, 0> packed_map;
};
-
#endif /* HB_SERIALIZE_HH */
projects / platform / upstream / harfbuzz.git / blobdiff