1

switch to raw ptr, clean moved objects, destructor

This commit is contained in:
2022-07-20 22:03:05 +02:00
parent 2ed5aba8c3
commit b2dfa72f3b

View File

@ -6,9 +6,9 @@
// ArrayList instead, without additional effort. // ArrayList instead, without additional effort.
#include "user/lib/List.h" #include "user/lib/List.h"
#include "user/lib/Logger.h"
#include "user/lib/mem/UniquePointer.h" #include "user/lib/mem/UniquePointer.h"
#include <cstddef> #include <cstddef>
#include <type_traits>
#include <utility> #include <utility>
// I put most of the implementation in the header because the templating makes it cumbersome to split // I put most of the implementation in the header because the templating makes it cumbersome to split
@ -23,16 +23,13 @@ private:
static constexpr const std::size_t default_cap = 10; // Arbitrary but very small because this isn't a real OS :( static constexpr const std::size_t default_cap = 10; // Arbitrary but very small because this isn't a real OS :(
static constexpr const std::size_t min_cap = 5; // Slots to allocate extra when array full static constexpr const std::size_t min_cap = 5; // Slots to allocate extra when array full
bse::unique_ptr<Type[]> buf; // Heap allocated as size needs to change during runtime Type* buf = nullptr; // Heap allocated as size needs to change during runtime
// Can't use Array for the same reason so we use a C Style array // Can't use Array for the same reason so we use a C Style array
// NOTE: I wouldn't normally use smart pointers for low level datastructures
// but here it doesn't hurt as the unique_ptr basically has no overhead
// (And it saved 2 deletes ¯\_(ツ)_/¯)
std::size_t buf_pos = 0; std::size_t buf_pos = 0;
std::size_t buf_cap = 0; std::size_t buf_cap = 0;
void init() { void init() {
buf = bse::make_unique<Type[]>(ArrayList::default_cap); buf = new Type[ArrayList::default_cap];
buf_cap = ArrayList::default_cap; buf_cap = ArrayList::default_cap;
} }
@ -43,7 +40,7 @@ private:
// Enlarges the buffer if we run out of space // Enlarges the buffer if we run out of space
std::size_t expand() { std::size_t expand() {
// Init if necessary // Init if necessary
if (!buf) { if (buf == nullptr) {
init(); init();
return buf_cap; // Dont have to realloc after init return buf_cap; // Dont have to realloc after init
} }
@ -53,15 +50,17 @@ private:
std::size_t new_cap = buf_cap + min_cap; std::size_t new_cap = buf_cap + min_cap;
// Alloc new array // Alloc new array
bse::unique_ptr<Type[]> new_buf = bse::make_unique<Type[]>(new_cap); Type* new_buf = new Type[new_cap];
// Swap current elements to new array // Swap current elements to new array
for (std::size_t i = 0; i < size(); ++i) { for (std::size_t i = 0; i < size(); ++i) {
new_buf[i] = std::move(buf[i]); // Should I have just used a regular pointer? new_buf[i] = std::move(buf[i]);
buf[i].~Type();
} }
// Move new array to buf, deleting the old array // Move new array to buf, deleting the old array
buf = std::move(new_buf); delete[] buf;
buf = new_buf;
buf_cap = new_cap; buf_cap = new_cap;
} }
@ -92,6 +91,7 @@ private:
// pos = 4 pos = 5 // pos = 4 pos = 5
for (std::size_t idx = size(); idx > i; --idx) { // idx > i so idx - 1 is never < 0 for (std::size_t idx = size(); idx > i; --idx) { // idx > i so idx - 1 is never < 0
buf[idx] = std::move(buf[idx - 1]); buf[idx] = std::move(buf[idx - 1]);
buf[idx - 1].~Type();
} }
// Only change pos if elements were copied // Only change pos if elements were copied
@ -118,13 +118,19 @@ private:
// pos = 3 pos = 2 // pos = 3 pos = 2
for (std::size_t idx = i; idx < size(); ++idx) { // idx < pos so idx + 1 is never outside of size limit for (std::size_t idx = i; idx < size(); ++idx) { // idx < pos so idx + 1 is never outside of size limit
buf[idx] = std::move(buf[idx + 1]); buf[idx] = std::move(buf[idx + 1]);
buf[idx + 1].~Type();
} }
return size(); return size();
} }
public: public:
~ArrayList() = default; // Buffer deletes itself (I hope) ~ArrayList() {
for (std::size_t i; i < size(); ++i) {
buf[i].~Type();
}
delete[] buf;
}
Iterator begin() override { Iterator begin() override {
return Iterator(&buf[0]); return Iterator(&buf[0]);
@ -135,6 +141,7 @@ public:
} }
// Returns new pos // Returns new pos
// NOTE: Insert copies
std::size_t insert_at(Type e, std::size_t i) override { std::size_t insert_at(Type e, std::size_t i) override {
if (i > size()) { if (i > size()) {
// Error: Space between elements // Error: Space between elements
@ -146,8 +153,12 @@ public:
return insert_last(std::forward<Type>(e)); return insert_last(std::forward<Type>(e));
} }
if constexpr (std::is_copy_assignable_v<Type>) {
copy_right(i); // Changes pos copy_right(i); // Changes pos
buf[i] = e; buf[i] = e;
} else {
return -1;
}
return size(); return size();
} }
@ -157,21 +168,35 @@ public:
} }
std::size_t insert_last(Type e) override { std::size_t insert_last(Type e) override {
expand(); if (!buf) {
init();
}
if constexpr (std::is_copy_assignable_v<Type>) {
buf[size()] = e; buf[size()] = e;
++buf_pos; ++buf_pos;
expand();
} else {
return -1;
}
return size(); return size();
} }
// Returns removed element // Returns removed element
// NOTE: Remove moves
std::optional<Type> remove_at(std::size_t i) override { std::optional<Type> remove_at(std::size_t i) override {
if (i >= size()) { if (i >= size()) {
// ERROR: No element here // ERROR: No element here
return std::nullopt; return std::nullopt;
} }
// Move moves the data if possible, copies otherwise
// It does not destroy the original object, an intact
// invariant is left so we have to destruct the old object
Type e = std::move(buf[i]); Type e = std::move(buf[i]);
buf[i].~Type(); // Cleanup the leftovers from the move
copy_left(i); copy_left(i);
return e; return e;
} }
@ -204,9 +229,14 @@ public:
return std::nullopt; return std::nullopt;
} }
// TODO: assignable or constructable?
if constexpr (std::is_copy_assignable_v<Type>) {
return buf[i]; return buf[i];
} }
return std::nullopt;
}
std::optional<Type> first() const override { std::optional<Type> first() const override {
return get(0); return get(0);
} }
@ -225,7 +255,7 @@ public:
void print(OutStream& out) const override { void print(OutStream& out) const override {
// Our stream cannot print all types so enable this only for debugging purposes (only int) // Our stream cannot print all types so enable this only for debugging purposes (only int)
if constexpr (std::is_same<Type, int>::value) { if constexpr (std::is_same_v<Type, int>) {
if (empty()) { if (empty()) {
out << "Print List (0 elements)" << endl; out << "Print List (0 elements)" << endl;
return; return;