harfbuzz/src/hb-vector.hh

471 lines
12 KiB
C++

/*
* Copyright © 2017,2018 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.
*
* Google Author(s): Behdad Esfahbod
*/
#ifndef HB_VECTOR_HH
#define HB_VECTOR_HH
#include "hb.hh"
#include "hb-array.hh"
#include "hb-meta.hh"
#include "hb-null.hh"
template <typename Type,
bool sorted=false>
struct hb_vector_t
{
typedef Type item_t;
static constexpr unsigned item_size = hb_static_size (Type);
using array_t = typename std::conditional<sorted, hb_sorted_array_t<Type>, hb_array_t<Type>>::type;
using c_array_t = typename std::conditional<sorted, hb_sorted_array_t<const Type>, hb_array_t<const Type>>::type;
hb_vector_t () = default;
hb_vector_t (std::initializer_list<Type> lst) : hb_vector_t ()
{
alloc (lst.size ());
for (auto&& item : lst)
push (item);
}
template <typename Iterable,
hb_requires (hb_is_iterable (Iterable))>
hb_vector_t (const Iterable &o) : hb_vector_t ()
{
auto iter = hb_iter (o);
if (iter.is_random_access_iterator)
alloc (hb_len (iter));
hb_copy (iter, *this);
}
hb_vector_t (const hb_vector_t &o) : hb_vector_t ()
{
alloc (o.length);
if (unlikely (in_error ())) return;
copy_vector (o);
}
hb_vector_t (hb_vector_t &&o)
{
allocated = o.allocated;
length = o.length;
arrayZ = o.arrayZ;
o.init ();
}
~hb_vector_t () { fini (); }
public:
int allocated = 0; /* == -1 means allocation failed. */
unsigned int length = 0;
public:
Type *arrayZ = nullptr;
void init ()
{
allocated = length = 0;
arrayZ = nullptr;
}
void init0 ()
{
}
void fini ()
{
shrink_vector (0);
hb_free (arrayZ);
init ();
}
void reset ()
{
if (unlikely (in_error ()))
/* Big Hack! We don't know the true allocated size before
* an allocation failure happened. But we know it was at
* least as big as length. Restore it to that and continue
* as if error did not happen. */
allocated = length;
resize (0);
}
friend void swap (hb_vector_t& a, hb_vector_t& b)
{
hb_swap (a.allocated, b.allocated);
hb_swap (a.length, b.length);
hb_swap (a.arrayZ, b.arrayZ);
}
hb_vector_t& operator = (const hb_vector_t &o)
{
reset ();
alloc (o.length);
if (unlikely (in_error ())) return *this;
copy_vector (o);
return *this;
}
hb_vector_t& operator = (hb_vector_t &&o)
{
hb_swap (*this, o);
return *this;
}
hb_bytes_t as_bytes () const
{ return hb_bytes_t ((const char *) arrayZ, get_size ()); }
bool operator == (const hb_vector_t &o) const { return as_array () == o.as_array (); }
bool operator != (const hb_vector_t &o) const { return !(*this == o); }
uint32_t hash () const { return as_array ().hash (); }
Type& operator [] (int i_)
{
unsigned int i = (unsigned int) i_;
if (unlikely (i >= length))
return Crap (Type);
return arrayZ[i];
}
const Type& operator [] (int i_) const
{
unsigned int i = (unsigned int) i_;
if (unlikely (i >= length))
return Null (Type);
return arrayZ[i];
}
Type& tail () { return (*this)[length - 1]; }
const Type& tail () const { return (*this)[length - 1]; }
explicit operator bool () const { return length; }
unsigned get_size () const { return length * item_size; }
/* Sink interface. */
template <typename T>
hb_vector_t& operator << (T&& v) { push (std::forward<T> (v)); return *this; }
array_t as_array () { return hb_array (arrayZ, length); }
c_array_t as_array () const { return hb_array (arrayZ, length); }
/* Iterator. */
typedef c_array_t iter_t;
typedef array_t writer_t;
iter_t iter () const { return as_array (); }
writer_t writer () { return as_array (); }
operator iter_t () const { return iter (); }
operator writer_t () { return writer (); }
/* Faster range-based for loop. */
Type *begin () const { return arrayZ; }
Type *end () const { return arrayZ + length; }
hb_sorted_array_t<Type> as_sorted_array ()
{ return hb_sorted_array (arrayZ, length); }
hb_sorted_array_t<const Type> as_sorted_array () const
{ return hb_sorted_array (arrayZ, length); }
template <typename T> explicit operator T * () { return arrayZ; }
template <typename T> explicit operator const T * () const { return arrayZ; }
Type * operator + (unsigned int i) { return arrayZ + i; }
const Type * operator + (unsigned int i) const { return arrayZ + i; }
Type *push ()
{
if (unlikely (!resize (length + 1)))
return &Crap (Type);
return std::addressof (arrayZ[length - 1]);
}
template <typename T,
typename T2 = Type,
hb_enable_if (!std::is_copy_constructible<T2>::value &&
std::is_copy_assignable<T>::value)>
Type *push (T&& v)
{
Type *p = push ();
if (p == &Crap (Type))
// If push failed to allocate then don't copy v, since this may cause
// the created copy to leak memory since we won't have stored a
// reference to it.
return p;
*p = std::forward<T> (v);
return p;
}
template <typename T,
typename T2 = Type,
hb_enable_if (std::is_copy_constructible<T2>::value)>
Type *push (T&& v)
{
if (unlikely (!alloc (length + 1)))
// If push failed to allocate then don't copy v, since this may cause
// the created copy to leak memory since we won't have stored a
// reference to it.
return &Crap (Type);
/* Emplace. */
length++;
Type *p = std::addressof (arrayZ[length - 1]);
return new (p) Type (std::forward<T> (v));
}
bool in_error () const { return allocated < 0; }
template <typename T = Type,
hb_enable_if (hb_is_trivially_copy_assignable(T))>
Type *
realloc_vector (unsigned new_allocated)
{
return (Type *) hb_realloc (arrayZ, new_allocated * sizeof (Type));
}
template <typename T = Type,
hb_enable_if (!hb_is_trivially_copy_assignable(T))>
Type *
realloc_vector (unsigned new_allocated)
{
Type *new_array = (Type *) hb_malloc (new_allocated * sizeof (Type));
if (likely (new_array))
{
for (unsigned i = 0; i < length; i++)
{
new (std::addressof (new_array[i])) Type ();
new_array[i] = std::move (arrayZ[i]);
arrayZ[i].~Type ();
}
hb_free (arrayZ);
}
return new_array;
}
template <typename T = Type,
hb_enable_if (hb_is_trivially_constructible(T))>
void
grow_vector (unsigned size)
{
memset (arrayZ + length, 0, (size - length) * sizeof (*arrayZ));
length = size;
}
template <typename T = Type,
hb_enable_if (!hb_is_trivially_constructible(T))>
void
grow_vector (unsigned size)
{
while (length < size)
{
length++;
new (std::addressof (arrayZ[length - 1])) Type ();
}
}
template <typename T = Type,
hb_enable_if (hb_is_trivially_copyable (T))>
void
copy_vector (const hb_vector_t &other)
{
length = other.length;
#ifndef HB_OPTIMIZE_SIZE
if (sizeof (T) >= sizeof (long long))
/* This runs faster because of alignment. */
for (unsigned i = 0; i < length; i++)
arrayZ[i] = other.arrayZ[i];
else
#endif
hb_memcpy ((void *) arrayZ, (const void *) other.arrayZ, length * item_size);
}
template <typename T = Type,
hb_enable_if (!hb_is_trivially_copyable (T) &&
std::is_copy_constructible<T>::value)>
void
copy_vector (const hb_vector_t &other)
{
length = 0;
while (length < other.length)
{
length++;
new (std::addressof (arrayZ[length - 1])) Type (other.arrayZ[length - 1]);
}
}
template <typename T = Type,
hb_enable_if (!hb_is_trivially_copyable (T) &&
!std::is_copy_constructible<T>::value &&
std::is_default_constructible<T>::value &&
std::is_copy_assignable<T>::value)>
void
copy_vector (const hb_vector_t &other)
{
length = 0;
while (length < other.length)
{
length++;
new (std::addressof (arrayZ[length - 1])) Type ();
arrayZ[length - 1] = other.arrayZ[length - 1];
}
}
void
shrink_vector (unsigned size)
{
while ((unsigned) length > size)
{
arrayZ[(unsigned) length - 1].~Type ();
length--;
}
}
void
shift_down_vector (unsigned i)
{
for (; i < length; i++)
arrayZ[i - 1] = std::move (arrayZ[i]);
}
/* Allocate for size but don't adjust length. */
bool alloc (unsigned int size)
{
if (unlikely (in_error ()))
return false;
if (likely (size <= (unsigned) allocated))
return true;
/* Reallocate */
unsigned int new_allocated = allocated;
while (size >= new_allocated)
new_allocated += (new_allocated >> 1) + 8;
Type *new_array = nullptr;
bool overflows =
(int) in_error () ||
(new_allocated < (unsigned) allocated) ||
hb_unsigned_mul_overflows (new_allocated, sizeof (Type));
if (likely (!overflows))
new_array = realloc_vector (new_allocated);
if (unlikely (!new_array))
{
allocated = -1;
return false;
}
arrayZ = new_array;
allocated = new_allocated;
return true;
}
bool resize (int size_, bool initialize = true)
{
unsigned int size = size_ < 0 ? 0u : (unsigned int) size_;
if (!alloc (size))
return false;
if (size > length)
{
if (initialize)
grow_vector (size);
}
else if (size < length)
{
if (initialize)
shrink_vector (size);
}
length = size;
return true;
}
Type pop ()
{
if (!length) return Null (Type);
Type v {std::move (arrayZ[length - 1])};
arrayZ[length - 1].~Type ();
length--;
return v;
}
void remove_ordered (unsigned int i)
{
if (unlikely (i >= length))
return;
shift_down_vector (i + 1);
arrayZ[length - 1].~Type ();
length--;
}
template <bool Sorted = sorted,
hb_enable_if (!Sorted)>
void remove_unordered (unsigned int i)
{
if (unlikely (i >= length))
return;
if (i != length - 1)
arrayZ[i] = std::move (arrayZ[length - 1]);
arrayZ[length - 1].~Type ();
length--;
}
void shrink (int size_)
{
unsigned int size = size_ < 0 ? 0u : (unsigned int) size_;
if (size >= length)
return;
shrink_vector (size);
}
/* Sorting API. */
void qsort (int (*cmp)(const void*, const void*) = Type::cmp)
{ as_array ().qsort (cmp); }
/* Unsorted search API. */
template <typename T>
Type *lsearch (const T &x, Type *not_found = nullptr)
{ return as_array ().lsearch (x, not_found); }
template <typename T>
const Type *lsearch (const T &x, const Type *not_found = nullptr) const
{ return as_array ().lsearch (x, not_found); }
template <typename T>
bool lfind (const T &x, unsigned *pos = nullptr) const
{ return as_array ().lfind (x, pos); }
/* Sorted search API. */
template <typename T,
bool Sorted=sorted, hb_enable_if (Sorted)>
Type *bsearch (const T &x, Type *not_found = nullptr)
{ return as_array ().bsearch (x, not_found); }
template <typename T,
bool Sorted=sorted, hb_enable_if (Sorted)>
const Type *bsearch (const T &x, const Type *not_found = nullptr) const
{ return as_array ().bsearch (x, not_found); }
template <typename T,
bool Sorted=sorted, hb_enable_if (Sorted)>
bool bfind (const T &x, unsigned int *i = nullptr,
hb_not_found_t not_found = HB_NOT_FOUND_DONT_STORE,
unsigned int to_store = (unsigned int) -1) const
{ return as_array ().bfind (x, i, not_found, to_store); }
};
template <typename Type>
using hb_sorted_vector_t = hb_vector_t<Type, true>;
#endif /* HB_VECTOR_HH */