X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=lib%2Futil.c;h=2402ac6e5a53de28e4702ebdaa347ea81587246c;hb=b86545a659a7146006e229d035f874106303f261;hp=811902afb99bd3f2274fdedbd194db9585b59e42;hpb=ddc4f8e27f231b35df0c73a16bacc17396fb00f3;p=openvswitch

diff --git a/lib/util.c b/lib/util.c
index 811902af..2402ac6e 100644
--- a/lib/util.c
+++ b/lib/util.c
@@ -296,7 +296,7 @@ set_program_name__(const char *argv0, const char *date, const char *time)
     program_name = slash ? slash + 1 : argv0;
 
     free(program_version);
-    program_version = xasprintf("%s (Open vSwitch) "VERSION BUILDNR"\n"
+    program_version = xasprintf("%s (Open vSwitch) "VERSION"\n"
                                 "Compiled %s %s\n",
                                 program_name, date, time);
 }
@@ -803,6 +803,54 @@ bitwise_copy(const void *src_, unsigned int src_len, unsigned int src_ofs,
     }
 }
 
+/* Zeros the 'n_bits' bits starting from bit 'dst_ofs' in 'dst'.  'dst' is
+ * 'dst_len' bytes long.
+ *
+ * If you consider all of 'dst' to be a single unsigned integer in network byte
+ * order, then bit N is the bit with value 2**N.  That is, bit 0 is the bit
+ * with value 1 in dst[dst_len - 1], bit 1 is the bit with value 2, bit 2 is
+ * the bit with value 4, ..., bit 8 is the bit with value 1 in dst[dst_len -
+ * 2], and so on.
+ *
+ * Required invariant:
+ *   dst_ofs + n_bits <= dst_len * 8
+ */
+void
+bitwise_zero(void *dst_, unsigned int dst_len, unsigned dst_ofs,
+             unsigned int n_bits)
+{
+    uint8_t *dst = dst_;
+
+    if (!n_bits) {
+        return;
+    }
+
+    dst += dst_len - (dst_ofs / 8 + 1);
+    dst_ofs %= 8;
+
+    if (dst_ofs) {
+        unsigned int chunk = MIN(n_bits, 8 - dst_ofs);
+
+        *dst &= ~(((1 << chunk) - 1) << dst_ofs);
+
+        n_bits -= chunk;
+        if (!n_bits) {
+            return;
+        }
+
+        dst--;
+    }
+
+    while (n_bits >= 8) {
+        *dst-- = 0;
+        n_bits -= 8;
+    }
+
+    if (n_bits) {
+        *dst &= ~((1 << n_bits) - 1);
+    }
+}
+
 /* Copies the 'n_bits' low-order bits of 'value' into the 'n_bits' bits
  * starting at bit 'dst_ofs' in 'dst', which is 'dst_len' bytes long.
  *