X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=lib%2Fbitmap.c;h=4b4e13e56051051ba61c5e288a9503a325789212;hb=HEAD;hp=d607526d5f55be3234ac0be98fe8b324819c5674;hpb=e368cad8ecf6dbf272b2a3775b2e3e5e2dc6a5cf;p=sliver-openvswitch.git

diff --git a/lib/bitmap.c b/lib/bitmap.c
index d607526d5..4b4e13e56 100644
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008, 2009, 2011 Nicira, Inc.
+ * Copyright (c) 2008, 2009, 2011, 2014 Nicira, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -17,6 +17,7 @@
 #include <config.h>
 #include "bitmap.h"
 #include <string.h>
+#include "util.h"
 
 /* Allocates and returns a bitmap initialized to all-1-bits. */
 unsigned long *
@@ -24,6 +25,7 @@ bitmap_allocate1(size_t n_bits)
 {
     size_t n_bytes = bitmap_n_bytes(n_bits);
     size_t n_longs = bitmap_n_longs(n_bits);
+    size_t r_bits = n_bits % BITMAP_ULONG_BITS;
     unsigned long *bitmap;
 
     /* Allocate and initialize most of the bitmap. */
@@ -32,7 +34,9 @@ bitmap_allocate1(size_t n_bits)
 
     /* 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;
+    if (r_bits) {
+        bitmap[n_longs - 1] = (1UL << r_bits) - 1;
+    }
 
     return bitmap;
 }
@@ -74,18 +78,34 @@ bitmap_equal(const unsigned long *a, const unsigned long *b, size_t n)
 }
 
 /* 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. */
+ * Returns the bit offset of the lowest-numbered bit set to 'target', or 'end'
+ * if all of the bits are set to '!target'. */
 size_t
-bitmap_scan(const unsigned long int *bitmap, size_t start, size_t end)
+bitmap_scan(const unsigned long int *bitmap, bool target,
+            size_t start, size_t end)
 {
     /* XXX slow */
     size_t i;
 
     for (i = start; i < end; i++) {
-        if (bitmap_is_set(bitmap, i)) {
+        if (bitmap_is_set(bitmap, i) == target) {
             break;
         }
     }
     return i;
 }
+
+/* Returns the number of 1-bits in the 'n'-bit bitmap at 'bitmap'. */
+size_t
+bitmap_count1(const unsigned long int *bitmap, size_t n)
+{
+    size_t i;
+    size_t count = 0;
+
+    BUILD_ASSERT(ULONG_MAX <= UINT64_MAX);
+    for (i = 0; i < BITMAP_N_LONGS(n); i++) {
+        count += count_1bits(bitmap[i]);
+    }
+
+    return count;
+}