From 98280238383dc390207827d09dc92e0459229134 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Juan=20Manuel=20Tom=C3=A1s?= Date: Sun, 24 May 2020 05:35:00 -0300 Subject: Rewrite in c++ --- point.cpp | 112 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 112 insertions(+) create mode 100644 point.cpp (limited to 'point.cpp') diff --git a/point.cpp b/point.cpp new file mode 100644 index 0000000..e31f5de --- /dev/null +++ b/point.cpp @@ -0,0 +1,112 @@ +#include +#include + +struct Point { + Page *page; + uint16_t index; + + Point() : page(nullptr), index(0) {} + Point(Page *page) : page(page), index(0) {} + Point(const Point& p) : page(p.page), index(p.index) {} + + uint16_t index_to_offset() { + if (index < page->gap_start) { + return index; + } else { + return index + (page->gap_end - page->gap_start); + } + } + + bool operator==(Point p) { + return page == p.page && index == p.index; + } + + uint8_t element() { + if (index == page->element_count) { + return !page->next ? 0 : page->next->elements[0]; + } else { + return page->elements[index_to_offset()]; + } + } + + void operator++(int) { + if (index < page->element_count) { + index++; + } else if (page->next) { + index = 1; + page = page->next; + } + } + + void operator--(int) { + if (index > 1) { + index--; + } else if (page->prev) { + page = page->prev; + index = page->element_count; + } else { + index = 0; + } + } + + uint64_t seek(uint8_t c, uint64_t limit) { + uint64_t travel_distance = 0; + while (element() && element() != c && travel_distance < limit) { + (*this)++; + travel_distance++; + } + return travel_distance; + } + + uint64_t rseek(uint8_t c, uint64_t limit) { + uint64_t travel_distance = 0; + while (index != 0 && element() != c && travel_distance < limit) { + (*this)--; + travel_distance++; + } + return travel_distance; + } + + void align_gap() { + while (page->gap_end < index_to_offset()) { + (*page)++; + } + while (page->gap_end > index_to_offset()) { + (*page)--; + } + } + + void push(uint8_t c) { + if (page->gap_start == page->gap_end) { + page->split(); + if (index >= PAGE_SIZE / 2) { + page = page->next; + index -= PAGE_SIZE / 2; + } + } + align_gap(); + page->push(c); + (*this)++; + } + + void pop() { + if (page->element_count == 1 && index == 1) { + if (page->prev) { + (*this)--; + delete page->next; + } else if (page->next) { + page->next->copy_to(page); + delete page->next; + index = 0; + } else { + page->pop(); + index = 0; + } + } else if (index > 0) { + align_gap(); + page->pop(); + (*this)--; + } + } + +}; -- cgit v1.2.3