From ee2e73cd7b5a1de68c8316e916c4ef3a88302bed Mon Sep 17 00:00:00 2001
From: Lars-Dominik Braun <lars@6xq.net>
Date: Sun, 4 Aug 2013 18:53:43 +0200
Subject: piano: Generic linked lists
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Introduces generic linked list structure and functions (like append,
delete, …). Removes a lot of copy&pasted code and improves code
readability/reusability.

Heads up: This change breaks libpiano’s ABI.
---
 src/libpiano/list.c | 112 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 112 insertions(+)
 create mode 100644 src/libpiano/list.c

(limited to 'src/libpiano/list.c')

diff --git a/src/libpiano/list.c b/src/libpiano/list.c
new file mode 100644
index 0000000..2e83ab0
--- /dev/null
+++ b/src/libpiano/list.c
@@ -0,0 +1,112 @@
+/*
+Copyright (c) 2013
+	Lars-Dominik Braun <lars@6xq.net>
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+
+#include <assert.h>
+
+#include "piano.h"
+
+#define PianoListForeach(l) for (; (l) != NULL; (l) = (void *) (l)->next)
+
+/*	append element e to list l, return new list head
+ */
+void *PianoListAppend (PianoListHead_t * const l, PianoListHead_t * const e) {
+	assert (e != NULL);
+	assert (e->next == NULL);
+
+	if (l == NULL) {
+		return e;
+	} else {
+		PianoListHead_t *curr = l;
+		while (curr->next != NULL) {
+			curr = curr->next;
+		}
+		curr->next = e;
+		return l;
+	}
+}
+
+/*	prepend element e to list l, returning new list head
+ */
+void *PianoListPrepend (PianoListHead_t * const l, PianoListHead_t * const e) {
+	assert (e != NULL);
+	assert (e->next == NULL);
+
+	e->next = l;
+	return e;
+}
+
+/*	delete element e from list l, return new list head
+ */
+void *PianoListDelete (PianoListHead_t * const l, PianoListHead_t * const e) {
+	assert (l != NULL);
+	assert (e != NULL);
+
+	PianoListHead_t *first = l, *curr = l, *prev = NULL;
+	PianoListForeach (curr) {
+		if (curr == e) {
+			/* found it! */
+			if (prev != NULL) {
+				prev->next = curr->next;
+			} else {
+				/* no successor */
+				first = curr->next;
+			}
+			break;
+		}
+		prev = curr;
+	}
+
+	return first;
+}
+
+/*	get nth element of list
+ */
+void *PianoListGet (PianoListHead_t * const l, const size_t n) {
+	PianoListHead_t *curr = l;
+	size_t i = n;
+
+	PianoListForeach (curr) {
+		if (i == 0) {
+			return curr;
+		}
+		--i;
+	}
+
+	return NULL;
+}
+
+/*	count elements in list l
+ */
+size_t PianoListCount (const PianoListHead_t * const l) {
+	assert (l != NULL);
+
+	size_t count = 0;
+	const PianoListHead_t *curr = l;
+
+	PianoListForeach (curr) {
+		++count;
+	}
+
+	return count;
+}
+
-- 
cgit v1.2.3