From 7db6ffa2267a210cd7bbffa0c55f68656e396234 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Juan=20Manuel=20Tom=C3=A1s?= <jtomas1815@gmail.com>
Date: Fri, 24 Apr 2020 15:35:29 -0300
Subject: Fix deleting first page corrupting page pointer

---
 page.c  |  8 ++++++++
 point.c | 11 +++++------
 2 files changed, 13 insertions(+), 6 deletions(-)

diff --git a/page.c b/page.c
index 1244df4..864623e 100644
--- a/page.c
+++ b/page.c
@@ -46,6 +46,13 @@ void split_page(struct page *back) {
 	back->next = front;
 }
 
+void copy_page(struct page *dest, struct page *src) {
+	memcpy(dest->elements, src->elements, PAGE_SIZE);
+	dest->gap_start = src->gap_start;
+	dest->gap_end = src->gap_end;
+	dest->element_count = src->element_count;
+}
+
 void free_page(struct page *page) {
 	if (page->prev) {
 		page->prev->next = page->next;
@@ -53,6 +60,7 @@ void free_page(struct page *page) {
 	if (page->next) {
 		page->next->prev = page->prev;
 	}
+	free(page->elements);
 	free(page);
 }
 
diff --git a/point.c b/point.c
index 7977a4e..27d62be 100644
--- a/point.c
+++ b/point.c
@@ -35,8 +35,8 @@ void move_point_backward(struct point *point) {
 	if (point->index > 1) {
 		point->index--;
 	} else if (point->page->prev) {
-		point->index = point->page->prev->element_count;
 		point->page = point->page->prev;
+		point->index = point->page->element_count;
 	} else {
 		point->index = 0;
 	}
@@ -65,15 +65,14 @@ void insert_at_point(struct point *point, uint8_t c) {
 }
 
 void delete_at_point(struct point *point) {
-	if (point->page->element_count == 1) {
+	if (point->page->element_count == 1 && point->index == 1) {
 		if (point->page->prev) {
-			point->page = point->page->prev;
-			point->index = point->page->element_count;
+			move_point_backward(point);
 			free_page(point->page->next);
 		} else if (point->page->next) {
-			point->page = point->page->next;
+			copy_page(point->page, point->page->next);
+			free_page(point->page->next);
 			point->index = 0;
-			free_page(point->page->prev);
 		} else {
 			align_gap(point);
 			delete_at_gap(point->page);
-- 
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