transmission/libtransmission/ptrarray.c

251 lines
5.1 KiB
C

/*
* This file Copyright (C) 2008-2014 Mnemosyne LLC
*
* It may be used under the GNU GPL versions 2 or 3
* or any future license endorsed by Mnemosyne LLC.
*
*/
#include <string.h> /* memmove */
#include "ptrarray.h"
#include "tr-assert.h"
#include "utils.h"
#define FLOOR 32
tr_ptrArray const TR_PTR_ARRAY_INIT = TR_PTR_ARRAY_INIT_STATIC;
void tr_ptrArrayDestruct(tr_ptrArray* p, PtrArrayForeachFunc func)
{
TR_ASSERT(p != NULL);
TR_ASSERT(p->items != NULL || p->n_items == 0);
if (func != NULL)
{
tr_ptrArrayForeach(p, func);
}
tr_free(p->items);
}
void tr_ptrArrayForeach(tr_ptrArray* t, PtrArrayForeachFunc func)
{
TR_ASSERT(t != NULL);
TR_ASSERT(t->items != NULL || t->n_items == 0);
TR_ASSERT(func != NULL);
for (int i = 0; i < t->n_items; ++i)
{
func(t->items[i]);
}
}
void** tr_ptrArrayPeek(tr_ptrArray* t, int* size)
{
*size = t->n_items;
return t->items;
}
int tr_ptrArrayInsert(tr_ptrArray* t, void* ptr, int pos)
{
if (t->n_items >= t->n_alloc)
{
t->n_alloc = MAX(FLOOR, t->n_alloc * 2);
t->items = tr_renew(void*, t->items, t->n_alloc);
}
if (pos < 0 || pos > t->n_items)
{
pos = t->n_items;
}
else
{
memmove(t->items + pos + 1, t->items + pos, sizeof(void*) * (t->n_items - pos));
}
t->items[pos] = ptr;
t->n_items++;
return pos;
}
void* tr_ptrArrayPop(tr_ptrArray* t)
{
void* ret = NULL;
if (t->n_items != 0)
{
ret = t->items[--t->n_items];
}
return ret;
}
void tr_ptrArrayErase(tr_ptrArray* t, int begin, int end)
{
if (end < 0)
{
end = t->n_items;
}
TR_ASSERT(begin >= 0);
TR_ASSERT(begin < end);
TR_ASSERT(end <= t->n_items);
memmove(t->items + begin, t->items + end, sizeof(void*) * (t->n_items - end));
t->n_items -= end - begin;
}
/**
***
**/
int tr_ptrArrayLowerBound(tr_ptrArray const* t, void const* ptr, tr_voidptr_compare_func compare, bool* exact_match)
{
int pos = -1;
bool match = false;
if (t->n_items == 0)
{
pos = 0;
}
else
{
int first = 0;
int last = t->n_items - 1;
for (;;)
{
int const half = (last - first) / 2;
int const c = compare(t->items[first + half], ptr);
if (c < 0)
{
int const new_first = first + half + 1;
if (new_first > last)
{
pos = new_first;
break;
}
first = new_first;
}
else if (c > 0)
{
int const new_last = first + half - 1;
if (new_last < first)
{
pos = first;
break;
}
last = new_last;
}
else
{
match = true;
pos = first + half;
break;
}
}
}
if (exact_match != NULL)
{
*exact_match = match;
}
return pos;
}
#ifndef TR_ENABLE_ASSERTS
#define assertArrayIsSortedAndUnique(array, compare) /* no-op */
#define assertIndexIsSortedAndUnique(array, pos, compare) /* no-op */
#else
static void assertArrayIsSortedAndUnique(tr_ptrArray const* t, tr_voidptr_compare_func compare)
{
for (int i = 0; i < t->n_items - 2; ++i)
{
TR_ASSERT(compare(t->items[i], t->items[i + 1]) < 0);
}
}
static void assertIndexIsSortedAndUnique(tr_ptrArray const* t, int pos, tr_voidptr_compare_func compare)
{
if (pos > 0)
{
TR_ASSERT(compare(t->items[pos - 1], t->items[pos]) < 0);
}
if (pos + 1 < t->n_items)
{
TR_ASSERT(compare(t->items[pos], t->items[pos + 1]) < 0);
}
}
#endif
int tr_ptrArrayInsertSorted(tr_ptrArray* t, void* ptr, tr_voidptr_compare_func compare)
{
int pos;
int ret;
assertArrayIsSortedAndUnique(t, compare);
pos = tr_ptrArrayLowerBound(t, ptr, compare, NULL);
ret = tr_ptrArrayInsert(t, ptr, pos);
assertIndexIsSortedAndUnique(t, ret, compare);
return ret;
}
void* tr_ptrArrayFindSorted(tr_ptrArray* t, void const* ptr, tr_voidptr_compare_func compare)
{
bool match = false;
int const pos = tr_ptrArrayLowerBound(t, ptr, compare, &match);
return match ? t->items[pos] : NULL;
}
static void* tr_ptrArrayRemoveSortedValue(tr_ptrArray* t, void const* ptr, tr_voidptr_compare_func compare)
{
int pos;
bool match;
void* ret = NULL;
assertArrayIsSortedAndUnique(t, compare);
pos = tr_ptrArrayLowerBound(t, ptr, compare, &match);
if (match)
{
ret = t->items[pos];
TR_ASSERT(compare(ret, ptr) == 0);
tr_ptrArrayErase(t, pos, pos + 1);
}
TR_ASSERT(ret == NULL || compare(ret, ptr) == 0);
return ret;
}
void tr_ptrArrayRemoveSortedPointer(tr_ptrArray* t, void const* ptr, tr_voidptr_compare_func compare)
{
void* removed = tr_ptrArrayRemoveSortedValue(t, ptr, compare);
#ifndef TR_ENABLE_ASSERTS
(void)removed;
#else
TR_ASSERT(removed != NULL);
TR_ASSERT(removed == ptr);
TR_ASSERT(tr_ptrArrayFindSorted(t, ptr, compare) == NULL);
#endif
}