mirror of
https://code.videolan.org/videolan/vlc
synced 2024-09-04 09:11:33 +02:00
![Alexandre Janniaux](/assets/img/avatar_default.png)
Include stddef.h to define size_t, as it is used later in the header. Signed-off-by: Rémi Denis-Courmont <remi@remlab.net>
642 lines
18 KiB
C
642 lines
18 KiB
C
/******************************************************************************
|
|
* vlc_vector.h
|
|
******************************************************************************
|
|
* Copyright (C) 2018 VLC authors and VideoLAN
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify it
|
|
* under the terms of the GNU Lesser General Public License as published by
|
|
* the Free Software Foundation; either version 2.1 of the License, or
|
|
* (at your option) any later version.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public License
|
|
* along with this program; if not, write to the Free Software Foundation,
|
|
* Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
|
|
*****************************************************************************/
|
|
#ifndef VLC_VECTOR_H
|
|
#define VLC_VECTOR_H
|
|
|
|
#include <stdbool.h>
|
|
#include <stddef.h>
|
|
|
|
/**
|
|
* \defgroup vector Vector
|
|
* \ingroup cext
|
|
* @{
|
|
* \file
|
|
* This provides convenience helpers for vectors.
|
|
*/
|
|
|
|
/**
|
|
* Vector struct body.
|
|
*
|
|
* A vector is a dynamic array, managed by the vlc_vector_* helpers.
|
|
*
|
|
* It is generic over the type of its items, so it is implemented as macros.
|
|
*
|
|
* To use a vector, a new type must be defined:
|
|
*
|
|
* \code
|
|
* struct vec_int VLC_VECTOR(int);
|
|
* \endcode
|
|
*
|
|
* The struct may be anonymous:
|
|
*
|
|
* \code
|
|
* struct VLC_VECTOR(const char *) names;
|
|
* \endcode
|
|
*
|
|
* It is convenient to define a typedef to an anonymous structure:
|
|
*
|
|
* \code
|
|
* typedef struct VLC_VECTOR(int) vec_int_t;
|
|
* \endcode
|
|
*
|
|
* Vector size is accessible via `vec.size`, and items are intended to be
|
|
* accessed directly, via `vec.data[i]`.
|
|
*
|
|
* Functions and macros having name ending with '_' are private.
|
|
*/
|
|
#define VLC_VECTOR(type) \
|
|
{ \
|
|
size_t cap; \
|
|
size_t size; \
|
|
type *data; \
|
|
}
|
|
|
|
/**
|
|
* Static initializer for a vector.
|
|
*/
|
|
#define VLC_VECTOR_INITIALIZER { 0, 0, NULL }
|
|
|
|
/**
|
|
* Initialize an empty vector.
|
|
*/
|
|
#define vlc_vector_init(pv) (void) \
|
|
( \
|
|
/* cannot be implemened as do-while(0), called from vlc_vector_clear() */ \
|
|
(pv)->cap = 0, \
|
|
(pv)->size = 0, \
|
|
(pv)->data = NULL \
|
|
)
|
|
|
|
/**
|
|
* Destroy a vector.
|
|
*
|
|
* The vector may not be used anymore unless vlc_vector_init() is called.
|
|
*/
|
|
#define vlc_vector_destroy(pv) \
|
|
free((pv)->data)
|
|
|
|
/**
|
|
* Clear a vector.
|
|
*
|
|
* Remove all items from the vector.
|
|
*/
|
|
#define vlc_vector_clear(pv) \
|
|
( \
|
|
/* cannot be implemened as do-while(0), called from vlc_vector_resize_() */ \
|
|
vlc_vector_destroy(pv), \
|
|
vlc_vector_init(pv) \
|
|
)
|
|
|
|
/**
|
|
* The minimal allocation size, in number of items.
|
|
*
|
|
* Private.
|
|
*/
|
|
#define VLC_VECTOR_MINCAP_ ((size_t) 10)
|
|
|
|
static inline size_t
|
|
vlc_vector_min_(size_t a, size_t b)
|
|
{
|
|
return a < b ? a : b;
|
|
}
|
|
|
|
static inline size_t
|
|
vlc_vector_max_(size_t a, size_t b)
|
|
{
|
|
return a > b ? a : b;
|
|
}
|
|
|
|
static inline size_t
|
|
vlc_vector_between_(size_t x, size_t min, size_t max)
|
|
{
|
|
return vlc_vector_max_(min, vlc_vector_min_(max, x));
|
|
}
|
|
|
|
static inline size_t
|
|
vlc_vector_enforce_size_t_(size_t value)
|
|
{
|
|
return value;
|
|
}
|
|
|
|
#define VLC_VECTOR_FAILFLAG_ (~(((size_t) -1) >> 1)) /* only the MSB */
|
|
|
|
/**
|
|
* Realloc data and update vector fields.
|
|
*
|
|
* On reallocation success, return the reallocated array and update the vector
|
|
* capacity and size.
|
|
*
|
|
* On reallocation failure, return `ptr`, keep `*psize` untouched, and set the
|
|
* failflag in `*pcap` to indicate allocation failure (to be consumed by
|
|
* `vlc_vector_test_and_reset_failflag_()`).
|
|
*
|
|
* This weird behavior allows to simultaneously:
|
|
* - not require compiler extensions like "statement expressions"
|
|
* - keep the vector data, size and capacity unchanged on reallocation failure
|
|
* - not require output variables other than vector fields from the caller
|
|
* - not violate the strict aliasing rules
|
|
* - report the reallocation status (success or failure)
|
|
*
|
|
* Private.
|
|
*
|
|
* \param ptr the current data to realloc
|
|
* \param count the requested capacity, in number of items
|
|
* \param size the size of one item
|
|
* \param pcap a pointer to the `cap` field of the vector [IN/OUT]
|
|
* \param psize a pointer to the `size` field of the vector [IN/OUT]
|
|
* \return the reallocated array, or `ptr` if reallocation failed
|
|
*/
|
|
static inline void *
|
|
vlc_vector_reallocdata_(void *ptr, size_t count, size_t size,
|
|
size_t *restrict pcap, size_t *restrict psize)
|
|
{
|
|
void *n = vlc_reallocarray(ptr, count, size);
|
|
if (!n)
|
|
{
|
|
/* this vector implementation guarantees that the capacity may not
|
|
* exceed SIZE_MAX/2 (to prevent overflows), so we can use the MSB to
|
|
* report allocation failure */
|
|
*pcap |= VLC_VECTOR_FAILFLAG_;
|
|
return ptr;
|
|
}
|
|
*pcap = count;
|
|
*psize = vlc_vector_min_(*psize, count);
|
|
return n;
|
|
}
|
|
|
|
/**
|
|
* Test and reset the fail flag.
|
|
*
|
|
* \retval true if the flag was set
|
|
* \retval false if the flag was not set
|
|
*/
|
|
static inline bool
|
|
vlc_vector_test_and_reset_failflag_(size_t *pcap)
|
|
{
|
|
if (*pcap & VLC_VECTOR_FAILFLAG_)
|
|
{
|
|
*pcap &= ~VLC_VECTOR_FAILFLAG_;
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
/**
|
|
* Realloc the underlying array to `newcap`.
|
|
*
|
|
* Private.
|
|
*
|
|
* \param pv a pointer to the vector
|
|
* \param newcap (size_t) the requested size
|
|
* \retval true if no allocation failed
|
|
* \retval false on allocation failure (the vector is left untouched)
|
|
*/
|
|
#define vlc_vector_realloc_(pv, newcap) \
|
|
( \
|
|
(pv)->data = vlc_vector_reallocdata_((pv)->data, newcap, \
|
|
sizeof(*(pv)->data), \
|
|
&(pv)->cap, &(pv)->size), \
|
|
!vlc_vector_test_and_reset_failflag_(&(pv)->cap) \
|
|
)
|
|
|
|
/**
|
|
* Resize the vector to `newcap` exactly.
|
|
*
|
|
* If `newcap` is 0, the vector is cleared.
|
|
*
|
|
* Private.
|
|
*
|
|
* \param pv a pointer to the vector
|
|
* \param newcap (size_t) the requested capacity
|
|
* \retval true if no allocation failed
|
|
* \retval false on allocation failure (the vector is left untouched)
|
|
*/
|
|
#define vlc_vector_resize_(pv, newcap) \
|
|
( \
|
|
(pv)->cap == (newcap) /* nothing to do */ || \
|
|
( \
|
|
(newcap) > 0 ? vlc_vector_realloc_(pv, newcap) \
|
|
: (vlc_vector_clear(pv), true) \
|
|
) \
|
|
)
|
|
|
|
static inline size_t
|
|
vlc_vector_growsize_(size_t value)
|
|
{
|
|
/* integer multiplication by 1.5 */
|
|
return value + (value >> 1);
|
|
}
|
|
|
|
/* SIZE_MAX/2 to fit in ssize_t, and so that cap*1.5 does not overflow. */
|
|
#define vlc_vector_max_cap_(pv) (SIZE_MAX / 2 / sizeof(*(pv)->data))
|
|
|
|
/**
|
|
* Increase the capacity of the vector to at least `mincap`.
|
|
*
|
|
* \param pv a pointer to the vector
|
|
* \param mincap (size_t) the requested capacity
|
|
* \retval true if no allocation failed
|
|
* \retval false on allocation failure (the vector is left untouched)
|
|
*/
|
|
#define vlc_vector_reserve(pv, mincap) \
|
|
/* avoid to allocate tiny arrays (< VLC_VECTOR_MINCAP_) */ \
|
|
vlc_vector_reserve_internal_(pv, \
|
|
vlc_vector_max_(mincap, VLC_VECTOR_MINCAP_))
|
|
|
|
#define vlc_vector_reserve_internal_(pv, mincap) \
|
|
( \
|
|
(mincap) <= (pv)->cap /* nothing to do */ || \
|
|
( \
|
|
(mincap) <= vlc_vector_max_cap_(pv) /* not too big */ && \
|
|
vlc_vector_realloc_(pv, \
|
|
/* multiply by 1.5, force between [mincap, maxcap] */ \
|
|
vlc_vector_between_(vlc_vector_growsize_((pv)->cap), \
|
|
mincap, \
|
|
vlc_vector_max_cap_(pv))) \
|
|
) \
|
|
)
|
|
|
|
/**
|
|
* Resize the vector so that its capacity equals its actual size.
|
|
*
|
|
* \param pv a pointer to the vector
|
|
*/
|
|
#define vlc_vector_shrink_to_fit(pv) \
|
|
(void) /* decreasing the size may not fail */ \
|
|
vlc_vector_resize_(pv, (pv)->size)
|
|
|
|
/**
|
|
* Resize the vector down automatically.
|
|
*
|
|
* Shrink only when necessary (in practice when cap > (size+5)*1.5)
|
|
*
|
|
* \param pv a pointer to the vector
|
|
*/
|
|
#define vlc_vector_autoshrink(pv) (void) \
|
|
( \
|
|
(pv)->cap <= VLC_VECTOR_MINCAP_ /* do not shrink to tiny length */ || \
|
|
(pv)->cap < vlc_vector_growsize_((pv)->size+5) /* no need to shrink */ || \
|
|
vlc_vector_resize_(pv, vlc_vector_max_((pv)->size+5, VLC_VECTOR_MINCAP_)) \
|
|
)
|
|
|
|
#define vlc_vector_check_same_ptr_type_(a, b) \
|
|
(void) ((a) == (b)) /* warn on type mismatch */
|
|
|
|
/**
|
|
* Push an item at the end of the vector.
|
|
*
|
|
* The amortized complexity is O(1).
|
|
*
|
|
* \param pv a pointer to the vector
|
|
* \param item the item to append
|
|
* \retval true if no allocation failed
|
|
* \retval false on allocation failure (the vector is left untouched)
|
|
*/
|
|
#define vlc_vector_push(pv, item) \
|
|
( \
|
|
vlc_vector_reserve(pv, (pv)->size + 1) && \
|
|
( \
|
|
(pv)->data[(pv)->size++] = (item), \
|
|
true \
|
|
) \
|
|
)
|
|
|
|
/**
|
|
* Append `count` items at the end of the vector.
|
|
*
|
|
* \param pv a pointer to the vector
|
|
* \param items the items array to append
|
|
* \param count the number of items in the array
|
|
* \retval true if no allocation failed
|
|
* \retval false on allocation failure (the vector is left untouched)
|
|
*/
|
|
#define vlc_vector_push_all(pv, items, count) \
|
|
vlc_vector_push_all_internal_(pv, items, vlc_vector_enforce_size_t_(count))
|
|
|
|
#define vlc_vector_push_all_internal_(pv, items, count) \
|
|
( \
|
|
vlc_vector_check_same_ptr_type_((pv)->data, items), \
|
|
vlc_vector_reserve(pv, (pv)->size + (count)) && \
|
|
( \
|
|
memcpy(&(pv)->data[(pv)->size], items, (count) * sizeof(*(pv)->data)), \
|
|
(pv)->size += (count), \
|
|
true \
|
|
) \
|
|
)
|
|
|
|
/**
|
|
* Insert an hole of size `count` to the given index.
|
|
*
|
|
* The items in range [index; size-1] will be moved. The items in the hole are
|
|
* left uninitialized.
|
|
*
|
|
* \param pv a pointer to the vector
|
|
* \param index the index where the hole is to be inserted
|
|
* \param count the number of items in the hole
|
|
* \retval true if no allocation failed
|
|
* \retval false on allocation failure (the vector is left untouched)
|
|
*/
|
|
#define vlc_vector_insert_hole(pv, index, count) \
|
|
vlc_vector_insert_hole_internal_(pv, vlc_vector_enforce_size_t_(index), \
|
|
vlc_vector_enforce_size_t_(count))
|
|
|
|
#define vlc_vector_insert_hole_internal_(pv, index, count) \
|
|
( \
|
|
vlc_vector_reserve(pv, (pv)->size + (count)) && \
|
|
( \
|
|
(index) == (pv)->size || \
|
|
( \
|
|
memmove(&(pv)->data[(index) + (count)], \
|
|
&(pv)->data[index], \
|
|
((pv)->size - (index)) * sizeof(*(pv)->data)), \
|
|
true \
|
|
) \
|
|
) && \
|
|
( \
|
|
(pv)->size += (count), \
|
|
true \
|
|
) \
|
|
)
|
|
|
|
/**
|
|
* Insert an item at the given index.
|
|
*
|
|
* The items in range [index; size-1] will be moved.
|
|
*
|
|
* \param pv a pointer to the vector
|
|
* \param index the index where the item is to be inserted
|
|
* \param item the item to append
|
|
* \retval true if no allocation failed
|
|
* \retval false on allocation failure (the vector is left untouched)
|
|
*/
|
|
#define vlc_vector_insert(pv, index, item) \
|
|
( \
|
|
vlc_vector_insert_hole(pv, index, 1) && \
|
|
( \
|
|
(pv)->data[index] = (item), \
|
|
true \
|
|
) \
|
|
)
|
|
|
|
/**
|
|
* Insert `count` items at the given index.
|
|
*
|
|
* The items in range [index; size-1] will be moved.
|
|
*
|
|
* \param pv a pointer to the vector
|
|
* \param index the index where the items are to be inserted
|
|
* \param items the items array to append
|
|
* \param count the number of items in the array
|
|
* \retval true if no allocation failed
|
|
* \retval false on allocation failure (the vector is left untouched)
|
|
*/
|
|
#define vlc_vector_insert_all(pv, index, items, count) \
|
|
( \
|
|
vlc_vector_check_same_ptr_type_((pv)->data, items), \
|
|
vlc_vector_insert_hole(pv, index, count) && \
|
|
( \
|
|
memcpy(&(pv)->data[index], items, (count) * sizeof(*(pv)->data)), \
|
|
true \
|
|
) \
|
|
)
|
|
|
|
/** Reverse a char array in place. */
|
|
static inline void
|
|
vlc_vector_reverse_array_(char *array, size_t len)
|
|
{
|
|
for (size_t i = 0; i < len / 2; ++i)
|
|
{
|
|
char c = array[i];
|
|
array[i] = array[len - i - 1];
|
|
array[len - i - 1] = c;
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Right-rotate a (char) array in place.
|
|
*
|
|
* For example, left-rotating a char array containing {1, 2, 3, 4, 5, 6} with
|
|
* distance 4 will result in {5, 6, 1, 2, 3, 4}.
|
|
*
|
|
* Private.
|
|
*/
|
|
static inline void
|
|
vlc_vector_rotate_array_left_(char *array, size_t len, size_t distance)
|
|
{
|
|
vlc_vector_reverse_array_(array, distance);
|
|
vlc_vector_reverse_array_(&array[distance], len - distance);
|
|
vlc_vector_reverse_array_(array, len);
|
|
}
|
|
|
|
/**
|
|
* Right-rotate a (char) array in place.
|
|
*
|
|
* For example, left-rotating a char array containing {1, 2, 3, 4, 5, 6} with
|
|
* distance 2 will result in {5, 6, 1, 2, 3, 4}.
|
|
*
|
|
* Private.
|
|
*/
|
|
static inline void
|
|
vlc_vector_rotate_array_right_(char *array, size_t len, size_t distance)
|
|
{
|
|
vlc_vector_rotate_array_left_(array, len, len - distance);
|
|
}
|
|
|
|
/**
|
|
* Move items in a (char) array in place.
|
|
*
|
|
* Move slice [index, count] to target.
|
|
*/
|
|
static inline void
|
|
vlc_vector_move_(char *array, size_t index, size_t count, size_t target)
|
|
{
|
|
if (index < target)
|
|
vlc_vector_rotate_array_left_(&array[index], target - index + count,
|
|
count);
|
|
else
|
|
vlc_vector_rotate_array_right_(&array[target], index - target + count,
|
|
count);
|
|
}
|
|
|
|
/**
|
|
* Move a slice of items to a given target index.
|
|
*
|
|
* The items in range [index; count] will be moved so that the *new* position
|
|
* of the first item is `target`.
|
|
*
|
|
* \param pv a pointer to the vector
|
|
* \param index the index of the first item to move
|
|
* \param count the number of items to move
|
|
* \param target the new index of the moved slice
|
|
*/
|
|
#define vlc_vector_move_slice(pv, index, count, target) \
|
|
vlc_vector_move_slice_internal_(pv, \
|
|
vlc_vector_enforce_size_t_(index), \
|
|
vlc_vector_enforce_size_t_(count), \
|
|
vlc_vector_enforce_size_t_(target))
|
|
|
|
#define vlc_vector_move_slice_internal_(pv, index, count, target) \
|
|
vlc_vector_move_((char *) (pv)->data, \
|
|
(index) * sizeof((pv)->data[0]), \
|
|
(count) * sizeof((pv)->data[0]), \
|
|
(target) * sizeof((pv)->data[0]))
|
|
|
|
/**
|
|
* Move an item to a given target index.
|
|
*
|
|
* The items will be moved so that its *new* position is `target`.
|
|
*
|
|
* \param pv a pointer to the vector
|
|
* \param index the index of the item to move
|
|
* \param target the new index of the moved item
|
|
*/
|
|
#define vlc_vector_move(pv, index, target) \
|
|
vlc_vector_move_slice(pv, index, 1, target)
|
|
|
|
/**
|
|
* Remove a slice of items, without shrinking the array.
|
|
*
|
|
* If you have no good reason to use the _noshrink() version, use
|
|
* vlc_vector_remove_slice() instead.
|
|
*
|
|
* The items in range [index+count; size-1] will be moved.
|
|
*
|
|
* \param pv a pointer to the vector
|
|
* \param index the index of the first item to remove
|
|
* \param count the number of items to remove
|
|
*/
|
|
#define vlc_vector_remove_slice_noshrink(pv, index, count) \
|
|
vlc_vector_remove_slice_noshrink_internal_(pv, \
|
|
vlc_vector_enforce_size_t_(index), \
|
|
vlc_vector_enforce_size_t_(count))
|
|
|
|
#define vlc_vector_remove_slice_noshrink_internal_(pv, index, count) \
|
|
do { \
|
|
if ((index) + (count) < (pv)->size) \
|
|
memmove(&(pv)->data[index], \
|
|
&(pv)->data[(index) + (count)], \
|
|
((pv)->size - (index) - (count)) * sizeof(*(pv)->data)); \
|
|
(pv)->size -= (count); \
|
|
} while (0)
|
|
|
|
/**
|
|
* Remove a slice of items.
|
|
*
|
|
* The items in range [index+count; size-1] will be moved.
|
|
*
|
|
* \param pv a pointer to the vector
|
|
* \param index the index of the first item to remove
|
|
* \param count the number of items to remove
|
|
*/
|
|
#define vlc_vector_remove_slice(pv, index, count) \
|
|
do { \
|
|
vlc_vector_remove_slice_noshrink(pv, index, count); \
|
|
vlc_vector_autoshrink(pv); \
|
|
} while (0)
|
|
|
|
/**
|
|
* Remove an item, without shrinking the array.
|
|
*
|
|
* If you have no good reason to use the _noshrink() version, use
|
|
* vlc_vector_remove() instead.
|
|
*
|
|
* The items in range [index+1; size-1] will be moved.
|
|
*
|
|
* \param pv a pointer to the vector
|
|
* \param index the index of item to remove
|
|
*/
|
|
#define vlc_vector_remove_noshrink(pv, index) \
|
|
vlc_vector_remove_slice_noshrink(pv, index, 1)
|
|
|
|
/**
|
|
* Remove an item.
|
|
*
|
|
* The items in range [index+1; size-1] will be moved.
|
|
*
|
|
* \param pv a pointer to the vector
|
|
* \param index the index of item to remove
|
|
*/
|
|
#define vlc_vector_remove(pv, index) \
|
|
do { \
|
|
vlc_vector_remove_noshrink(pv, index); \
|
|
vlc_vector_autoshrink(pv); \
|
|
} while (0)
|
|
|
|
/**
|
|
* Remove an item.
|
|
*
|
|
* The removed item is replaced by the last item of the vector.
|
|
*
|
|
* This does not preserve ordering, but is O(1). This is useful when the order
|
|
* of items is not meaningful.
|
|
*
|
|
* \param pv a pointer to the vector
|
|
* \param index the index of item to remove
|
|
*/
|
|
#define vlc_vector_swap_remove(pv, index) \
|
|
(pv)->data[index] = (pv)->data[--(pv)->size]
|
|
|
|
/**
|
|
* Return the index of an item.
|
|
*
|
|
* Iterate over all items to find a given item.
|
|
*
|
|
* Use only for vectors of primitive types or pointers.
|
|
*
|
|
* The result is written to `*(pidx)`:
|
|
* - the index of the item if it is found;
|
|
* - -1 if it is not found.
|
|
*
|
|
* \param pv a pointer to the vector
|
|
* \param item the item to find (compared with ==)
|
|
* \param a pointer to the result (ssize_t *) [OUT]
|
|
*/
|
|
#define vlc_vector_index_of(pv, item, pidx) \
|
|
do { \
|
|
ssize_t *out = pidx; /* warning/error on type mismatch */ \
|
|
size_t vlc_vector_find_idx_; \
|
|
for (vlc_vector_find_idx_ = 0; \
|
|
vlc_vector_find_idx_ < (pv)->size; \
|
|
++vlc_vector_find_idx_) \
|
|
if ((pv)->data[vlc_vector_find_idx_] == (item)) \
|
|
break; \
|
|
*out = vlc_vector_find_idx_ == (pv)->size ? -1 : \
|
|
(ssize_t) vlc_vector_find_idx_; \
|
|
} while (0)
|
|
|
|
/**
|
|
* For-each loop.
|
|
*
|
|
* Use only for vectors of primitive types or pointers (every struct would be
|
|
* copied for a vector of structs).
|
|
*
|
|
* \param item the iteration variable [OUT]
|
|
* \param pv a pointer to the vector [OUT]
|
|
*/
|
|
#define vlc_vector_foreach(item, pv) \
|
|
for (size_t vlc_vector_idx_##item = 0; \
|
|
vlc_vector_idx_##item < (pv)->size && \
|
|
((item) = (pv)->data[vlc_vector_idx_##item], true); \
|
|
++vlc_vector_idx_##item)
|
|
|
|
/** @} */
|
|
|
|
#endif
|