X-Git-Url: http://pileus.org/git/?p=wmpus;a=blobdiff_plain;f=util.c;h=30df76c28a39d2e25320226545be0bfc8253904b;hp=24100f2243d6576d8481109a17a43c614d4a7c1a;hb=HEAD;hpb=5dd54ab27b27c888741e5700aad89226009eb449

diff --git a/util.c b/util.c
index 24100f2..30df76c 100644
--- a/util.c
+++ b/util.c
@@ -1,9 +1,25 @@
+/*
+ * Copyright (c) 2011, Andy Spencer <andy753421@gmail.com>
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+ * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+ */
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <stdarg.h>
 
 #include "util.h"
 
+/* Doubly linked lists */
 list_t *list_insert(list_t *next, void *data)
 {
 	list_t *node = new0(list_t);
@@ -15,10 +31,22 @@ list_t *list_insert(list_t *next, void *data)
 	return node;
 }
 
+void list_insert_after(list_t *prev, void *data)
+{
+	// prev must be valid,
+	// as we cannot return the original list head
+	list_t *node = new0(list_t);
+	node->data = data;
+	node->prev = prev;
+	node->next = prev->next;
+	prev->next = node;
+	if (node->next) node->next->prev = node;
+}
+
 list_t *list_append(list_t *head, void *data)
 {
 	list_t *last = head;
-	while (last->next)
+	while (last && last->next)
 		last = last->next;
 	list_t *node = new0(list_t);
 	node->data = data;
@@ -27,12 +55,14 @@ list_t *list_append(list_t *head, void *data)
 	return last ? head : node;
 }
 
-list_t *list_remove(list_t *head, list_t *node)
+list_t *list_remove(list_t *head, list_t *node, int freedata)
 {
 	list_t *next = node->next;
 	list_t *prev = node->prev;
 	if (next) next->prev = prev;
 	if (prev) prev->next = next;
+	if (freedata)
+		free(node->data);
 	free(node);
 	return head == node ? next : head;
 }
@@ -45,7 +75,64 @@ int list_length(list_t *node)
 	return len;
 }
 
+list_t *list_last(list_t *list)
+{
+	while (list && list->next)
+		list = list->next;
+	return list;
+}
+
+list_t *list_find(list_t *list, void *data)
+{
+	for (list_t *cur = list; cur; cur = cur->next)
+		if (cur->data == data)
+			return cur;
+	return NULL;
+}
+
+list_t *list_sort(list_t *list, int rev, int (*func)(void *a, void*b))
+{
+	if (list == NULL || list->next == NULL)
+		return list;
+
+	/* Split list */
+	list_t *sides[2] = {NULL, NULL};
+	for (int i = 0; list; i=(i+1)%2) {
+		list_t *head = list;
+		list = list->next;
+		head->next = sides[i];
+		sides[i]   = head;
+	}
+
+	/* Sort sides */
+	sides[0] = list_sort(sides[0], !rev, func);
+	sides[1] = list_sort(sides[1], !rev, func);
+
+	/* Merge sides */
+	while (sides[0] || sides[1]) {
+		int i = sides[0] == NULL ? 1 :
+		        sides[1] == NULL ? 0 :
+			func(sides[0]->data,
+			     sides[1]->data) > 0 ? !!rev : !rev;
+		list_t *head = sides[i];
+		sides[i] = sides[i]->next;
+		head->next = list;
+		head->prev = NULL;
+		if (list)
+			list->prev = head;
+		list = head;
+	}
+	return list;
+}
+
 /* Misc */
+int str2num(char *str, int def)
+{
+	char *end = NULL;
+	int num = strtol(str, &end, 10);
+	return end && *end == '\0' ? num : def;
+}
+
 int error(char *fmt, ...)
 {
 	va_list ap;