1 files changed, 124 insertions, 0 deletions
diff --git a/qpid/extras/dispatch/src/bitmask.c b/qpid/extras/dispatch/src/bitmask.c
new file mode 100644
index 0000000000..88ba69dde1
--- /dev/null
+++ b/qpid/extras/dispatch/src/bitmask.c
@@ -0,0 +1,124 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ * 
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ * 
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+#include <qpid/dispatch/bitmask.h>
+#include <qpid/dispatch/alloc.h>
+#include <assert.h>
+
+#define DX_BITMASK_LONGS 16
+#define DX_BITMASK_BITS  (DX_BITMASK_LONGS * 64)
+
+struct dx_bitmask_t {
+    uint64_t array[DX_BITMASK_LONGS];
+    int      first_set;
+};
+
+ALLOC_DECLARE(dx_bitmask_t);
+ALLOC_DEFINE(dx_bitmask_t);
+
+#define MASK_INDEX(num)  (num / 64)
+#define MASK_ONEHOT(num) (((uint64_t) 1) << (num % 64))
+#define FIRST_NONE    -1
+#define FIRST_UNKNOWN -2
+
+
+int dx_bitmask_width()
+{
+    return DX_BITMASK_BITS;
+}
+
+
+dx_bitmask_t *dx_bitmask(int initial)
+{
+    dx_bitmask_t *b = new_dx_bitmask_t();
+    if (initial)
+        dx_bitmask_set_all(b);
+    else
+        dx_bitmask_clear_all(b);
+    return b;
+}
+
+
+void dx_bitmask_free(dx_bitmask_t *b)
+{
+    free_dx_bitmask_t(b);
+}
+
+
+void dx_bitmask_set_all(dx_bitmask_t *b)
+{
+    for (int i = 0; i < DX_BITMASK_LONGS; i++)
+        b->array[i] = 0xFFFFFFFFFFFFFFFF;
+    b->first_set = 0;
+}
+
+
+void dx_bitmask_clear_all(dx_bitmask_t *b)
+{
+    for (int i = 0; i < DX_BITMASK_LONGS; i++)
+        b->array[i] = 0;
+    b->first_set = FIRST_NONE;
+}
+
+
+void dx_bitmask_set_bit(dx_bitmask_t *b, int bitnum)
+{
+    assert(bitnum < DX_BITMASK_BITS);
+    b->array[MASK_INDEX(bitnum)] |= MASK_ONEHOT(bitnum);
+    if (b->first_set > bitnum || b->first_set < 0)
+        b->first_set = bitnum;
+}
+
+
+void dx_bitmask_clear_bit(dx_bitmask_t *b, int bitnum)
+{
+    assert(bitnum < DX_BITMASK_BITS);
+    b->array[MASK_INDEX(bitnum)] &= ~(MASK_ONEHOT(bitnum));
+    if (b->first_set == bitnum)
+        b->first_set = FIRST_UNKNOWN;
+}
+
+
+int dx_bitmask_value(dx_bitmask_t *b, int bitnum)
+{
+    return (b->array[MASK_INDEX(bitnum)] & MASK_ONEHOT(bitnum)) ? 1 : 0;
+}
+
+
+int dx_bitmask_first_set(dx_bitmask_t *b, int *bitnum)
+{
+    if (b->first_set == FIRST_UNKNOWN) {
+        b->first_set = FIRST_NONE;
+        for (int i = 0; i < DX_BITMASK_LONGS; i++)
+            if (b->array[i]) {
+                for (int j = 0; j < 64; j++)
+                    if ((((uint64_t) 1) << j) & b->array[i]) {
+                        b->first_set = i * 64 + j;
+                        break;
+                    }
+                break;
+            }
+    }
+
+    if (b->first_set == FIRST_NONE)
+        return 0;
+    *bitnum = b->first_set;
+    return 1;
+}
+