Merge tag 'upstream/4.0.5+dfsg1' into samba_4.0_ivo

[abartlet/samba-debian.git] / lib / ccan / list / list.c

diff --git a/lib/ccan/list/list.c b/lib/ccan/list/list.c
new file mode 100644 (file)
index 0000000..380212a
--- /dev/null
+++ b/lib/ccan/list/list.c
@@ -0,0 +1,43 @@
+/* Licensed under LGPLv2.1+ - see LICENSE file for details */
+#include <stdio.h>
+#include <stdlib.h>
+#include "list.h"
+
+static void *corrupt(const char *abortstr,
+                    const struct ccan_list_node *head,
+                    const struct ccan_list_node *node,
+                    unsigned int count)
+{
+       if (abortstr) {
+               fprintf(stderr,
+                       "%s: prev corrupt in node %p (%u) of %p\n",
+                       abortstr, node, count, head);
+               abort();
+       }
+       return NULL;
+}
+
+struct ccan_list_node *ccan_list_check_node(const struct ccan_list_node *node,
+                                 const char *abortstr)
+{
+       const struct ccan_list_node *p, *n;
+       int count = 0;
+
+       for (p = node, n = node->next; n != node; p = n, n = n->next) {
+               count++;
+               if (n->prev != p)
+                       return corrupt(abortstr, node, n, count);
+       }
+       /* Check prev on head node. */
+       if (node->prev != p)
+               return corrupt(abortstr, node, node, 0);
+
+       return (struct ccan_list_node *)node;
+}
+
+struct ccan_list_head *ccan_list_check(const struct ccan_list_head *h, const char *abortstr)
+{
+       if (!ccan_list_check_node(&h->n, abortstr))
+               return NULL;
+       return (struct ccan_list_head *)h;
+}