liblist-c

commit d7590f411fed9f98cae458162c28568761b8fb95
parent f92b7a2e1ac819ed3291b834dbf1b6a008c2873d
Author: Louis Burda <quent.burda@gmail.com>
Date:   Wed,  2 Mar 2022 19:42:17 +0100

Simplified sorting interface

Diffstat:
M
include/list.h
 | 
8
++++----
A
include/test.h
 | 
0

M
src/list.c
 | 
23
+++++++++++------------
M
src/test.c
 | 
11
+++++++----

4 files changed, 22 insertions(+), 20 deletions(-)
diff --git a/include/list.h b/include/list.h
@@ -37,10 +37,10 @@ void list_clear(struct list *list);
 bool list_empty(struct list *list);
 size_t list_len(struct list *list);
 
-void list_insert_sorted(struct list *list, struct link *link,
-	int (*compare)(struct link *a, struct link *b));
-void list_sort(struct list *list,
-	int (*compare)(struct link *a, struct link *b));
+void list_insert_sorted(struct list *list, struct link *link, bool ascending,
+	bool (*in_order)(struct link *a, struct link *b));
+void list_sort(struct list *list, bool ascending,
+	bool (*in_order)(struct link *a, struct link *b));
 
 int list_index(struct list *list, struct link *link);
 
diff --git a/include/test.h b/include/test.h
diff --git a/src/list.c b/src/list.c
@@ -111,18 +111,18 @@ list_len(struct list *list)
 }
 
 void
-list_insert_sorted(struct list *list, struct link *insert,
-	int (*compare)(struct link *a, struct link *b))
+list_insert_sorted(struct list *list, struct link *insert, bool ascending,
+	bool (*in_order)(struct link *a, struct link *b))
 {
 	struct link *link;
 
-	ASSERT(list != NULL && insert != NULL && compare != NULL);
+	ASSERT(list != NULL && insert != NULL && in_order != NULL);
 
 	/* Simple Insertion Sort */
 	/* cmp(a,b) -> (a-b) */
 
 	for (LIST_ITER(list, link)) {
-		if (compare(link, insert) >= 0) {
+		if (ascending == in_order(insert, link)) {
 			link_prepend(link, insert);
 			return;
 		}
@@ -132,26 +132,25 @@ list_insert_sorted(struct list *list, struct link *insert,
 }
 
 void
-list_sort(struct list *list, int (*compare)(struct link *a, struct link *b))
+list_sort(struct list *list, bool ascending,
+	bool (*in_order)(struct link *a, struct link *b))
 {
 	struct link *link, *cmp, *next;
 
-	ASSERT(list != NULL && compare != NULL);
-
-	/* Simple Insertion Sort */
-	/* cmp(a,b) -> (a-b) */
+	ASSERT(list != NULL && in_order != NULL);
 
+	/* Insertion Sort */
 	link = list->head.next;
 	while (LIST_INNER(link)) {
 		next = link->next;
 		cmp = link->prev;
 		while (LIST_INNER(cmp)) {
-			if (compare(cmp, link) < 0) {
-				link_append(cmp, link_pop(link));
+			if (ascending == in_order(cmp, link))
 				break;
-			}
 			cmp = cmp->prev;
 		}
+		if (cmp != link->prev)
+			link_append(cmp, link_pop(link));
 		link = next;
 	}
 }
diff --git a/src/test.c b/src/test.c
@@ -10,7 +10,7 @@ struct arg {
 	struct link link;
 };
 
-int
+bool
 test_sort(struct link *link1, struct link *link2)
 {
 	struct arg *arg1, *arg2;
@@ -18,7 +18,7 @@ test_sort(struct link *link1, struct link *link2)
 	arg1 = LINK_UPCAST(link1, struct arg, link);
 	arg2 = LINK_UPCAST(link2, struct arg, link);
 
-	return strcmp(arg1->str, arg2->str);
+	return strcmp(arg1->str, arg2->str) <= 0;
 }
 
 int
@@ -31,7 +31,10 @@ main(int argc, const char **argv)
 
 	list_init(&list);
 
-	for (arg = argv; *arg; arg++) {
+	if (argc < 3)
+		return 1;
+
+	for (arg = &argv[2]; *arg; arg++) {
 		item = malloc(sizeof(struct arg));
 		if (!item) return 0;
 		item->str = *arg;
@@ -39,7 +42,7 @@ main(int argc, const char **argv)
 		list_push_back(&list, &item->link);
 	}
 
-	list_sort(&list, test_sort);
+	list_sort(&list, atoi(argv[1]), test_sort);
 
 	for (LIST_ITER(&list, iter)) {
 		item = LINK_UPCAST(iter, struct arg, link);