X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lib%2Fbitmap.c;h=d607526d5f55be3234ac0be98fe8b324819c5674;hb=e892d5ffb5749c0534fecd903e3e6a76819f1346;hp=cab7e6d261e833add569b6d20edb355febfa870e;hpb=064af42167bf4fc9aaea2702d80ce08074b889c0;p=sliver-openvswitch.git

diff --git a/lib/bitmap.c b/lib/bitmap.c
index cab7e6d26..d607526d5 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -1,23 +1,42 @@
 /*
- * Copyright (c) 2008 Nicira Networks.
+ * Copyright (c) 2008, 2009, 2011 Nicira, Inc.
  *
- * 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.
+ * Licensed 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:
  *
- * 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
- * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ *     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 <config.h>
 #include "bitmap.h"
 #include <string.h>
 
+/* Allocates and returns a bitmap initialized to all-1-bits. */
+unsigned long *
+bitmap_allocate1(size_t n_bits)
+{
+    size_t n_bytes = bitmap_n_bytes(n_bits);
+    size_t n_longs = bitmap_n_longs(n_bits);
+    unsigned long *bitmap;
+
+    /* Allocate and initialize most of the bitmap. */
+    bitmap = xmalloc(n_bytes);
+    memset(bitmap, 0xff, n_bytes);
+
+    /* Ensure that the last "unsigned long" in the bitmap only has as many
+     * 1-bits as there actually should be. */
+    bitmap[n_longs - 1] = (1UL << (n_bits % BITMAP_ULONG_BITS)) - 1;
+
+    return bitmap;
+}
+
 /* Sets 'count' consecutive bits in 'bitmap', starting at bit offset 'start',
  * to 'value'. */
 void
@@ -53,3 +72,20 @@ bitmap_equal(const unsigned long *a, const unsigned long *b, size_t n)
     }
     return true;
 }
+
+/* Scans 'bitmap' from bit offset 'start' to 'end', excluding 'end' itself.
+ * Returns the bit offset of the lowest-numbered bit set to 1, or 'end' if
+ * all of the bits are set to 0. */
+size_t
+bitmap_scan(const unsigned long int *bitmap, size_t start, size_t end)
+{
+    /* XXX slow */
+    size_t i;
+
+    for (i = start; i < end; i++) {
+        if (bitmap_is_set(bitmap, i)) {
+            break;
+        }
+    }
+    return i;
+}