bitmap: Add new functions.

These will be used in an upcoming commit.

Signed-off-by: Ben Pfaff <blp@nicira.com>
Acked-by: Jarno Rajahalme <jrajahalme@nicira.com>

diff --git a/lib/bitmap.c b/lib/bitmap.c
index 4b4e13e..7889aa1 100644 (file)
--- a/lib/bitmap.c
+++ b/lib/bitmap.c
@@ -109,3 +109,47 @@ bitmap_count1(const unsigned long int *bitmap, size_t n)
 
     return count;
 }
+
+/* "dst &= arg;" for n-bit dst and arg.  */
+void
+bitmap_and(unsigned long *dst, const unsigned long *arg, size_t n)
+{
+    size_t i;
+
+    for (i = 0; i < BITMAP_N_LONGS(n); i++) {
+        dst[i] &= arg[i];
+    }
+}
+
+/* "dst |= arg;" for n-bit dst and arg.  */
+void
+bitmap_or(unsigned long *dst, const unsigned long *arg, size_t n)
+{
+    size_t i;
+
+    for (i = 0; i < BITMAP_N_LONGS(n); i++) {
+        dst[i] |= arg[i];
+    }
+}
+
+/* "dst = ~dst;" for n-bit dst.  */
+void
+bitmap_not(unsigned long *dst, size_t n)
+{
+    size_t i;
+
+    for (i = 0; i < n / BITMAP_ULONG_BITS; i++) {
+        dst[i] = ~dst[i];
+    }
+    if (n % BITMAP_ULONG_BITS) {
+        dst[i] ^= (1u << (n % BITMAP_ULONG_BITS)) - 1;
+    }
+}
+
+/* Returns true if all of the 'n' bits in 'bitmap' are 0,
+ * false if at least one bit is a 1.*/
+bool
+bitmap_is_all_zeros(const unsigned long *bitmap, size_t n)
+{
+    return bitmap_scan(bitmap, true, 0, n) == n;
+}

diff --git a/lib/bitmap.h b/lib/bitmap.h
index afe6151..ace091f 100644 (file)
--- a/lib/bitmap.h
+++ b/lib/bitmap.h
@@ -104,6 +104,12 @@ size_t bitmap_scan(const unsigned long int *, bool target,
                    size_t start, size_t end);
 size_t bitmap_count1(const unsigned long *, size_t n);
 
+void bitmap_and(unsigned long *dst, const unsigned long *arg, size_t n);
+void bitmap_or(unsigned long *dst, const unsigned long *arg, size_t n);
+void bitmap_not(unsigned long *dst, size_t n);
+
+bool bitmap_is_all_zeros(const unsigned long *, size_t n);
+
 #define BITMAP_FOR_EACH_1(IDX, SIZE, BITMAP) \
     for ((IDX) = bitmap_scan(BITMAP, 1, 0, SIZE); (IDX) < (SIZE);    \
          (IDX) = bitmap_scan(BITMAP, 1, (IDX) + 1, SIZE))