X-Git-Url: http://git.ozlabs.org/?p=ccan;a=blobdiff_plain;f=ccan%2Ftake%2Ftake.c;fp=ccan%2Ftake%2Ftake.c;h=73e5c29d206fcf5a5cf23e7b6f8d4836a3d06fc4;hp=0000000000000000000000000000000000000000;hb=c8a55bb39404772d459f0153f07db7ecc91ecfd0;hpb=84b29c907c7608a024f65c4ef6803a1f5bb80ccd

diff --git a/ccan/take/take.c b/ccan/take/take.c
new file mode 100644
index 00000000..73e5c29d
--- /dev/null
+++ b/ccan/take/take.c
@@ -0,0 +1,86 @@
+/* CC0 (Public domain) - see LICENSE file for details */
+#include <ccan/take/take.h>
+#include <ccan/likely/likely.h>
+#include <stdlib.h>
+#include <string.h>
+
+static const void **takenarr;
+static size_t max_taken, num_taken;
+static size_t allocfail;
+static void (*allocfailfn)(const void *p);
+
+void *take_(const void *p)
+{
+	if (unlikely(num_taken == max_taken)) {
+		const void **new;
+
+		new = realloc(takenarr, sizeof(*takenarr) * (max_taken+1));
+		if (unlikely(!new)) {
+			if (allocfailfn) {
+				allocfail++;
+				allocfailfn(p);
+				return NULL;
+			}
+			/* Otherwise we leak p. */
+			return (void *)p;
+		}
+		takenarr = new;
+		max_taken++;
+	}
+	takenarr[num_taken++] = p;
+	return (void *)p;
+}
+
+static size_t find_taken(const void *p)
+{
+	size_t i;
+
+	for (i = 0; i < num_taken; i++) {
+		if (takenarr[i] == p)
+			return i+1;
+	}
+	return 0;
+}
+
+bool taken(const void *p)
+{
+	size_t i;
+
+	if (!p && unlikely(allocfail)) {
+		allocfail--;
+		return true;
+	}
+
+	i = find_taken(p);
+	if (!i)
+		return false;
+
+	memmove(&takenarr[i-1], &takenarr[i],
+		(--num_taken - (i - 1))*sizeof(takenarr[0]));
+	return true;
+}
+
+bool is_taken(const void *p)
+{
+	if (!p && unlikely(allocfail))
+		return true;
+
+	return find_taken(p) > 0;
+}
+
+bool taken_any(void)
+{
+	return num_taken != 0;
+}
+
+void take_cleanup(void)
+{
+	max_taken = num_taken = 0;
+	free(takenarr);
+	takenarr = NULL;
+}
+
+void take_allocfail(void (*fn)(const void *p))
+{
+	allocfailfn = fn;
+}