util: New function bitwise_one().

It's the obvious counterpart to bitwise_zero().

Signed-off-by: Ben Pfaff <blp@nicira.com>

2 files changed, 45 insertions, 1 deletions

diff --git a/tests/library.at b/tests/library.at
index ca5f29ca..dce69dea 100644
--- a/tests/library.at
+++ b/tests/library.at
@@ -100,7 +100,8 @@ nibble   0   1   2   3   4   5   6   7   8   9  10  11  12  13  14  15
 ])
 AT_CLEANUP
 
-AT_SETUP([test log_2_floor])
+AT_SETUP([test utility functions])
+AT_KEYWORDS([util])
 AT_CHECK([test-util])
 AT_CLEANUP
 
diff --git a/tests/test-util.c b/tests/test-util.c
index 82d08610..ed98295b 100644
--- a/tests/test-util.c
+++ b/tests/test-util.c
@@ -143,6 +143,47 @@ check_bitwise_zero(void)
     }
 }
 
+static void
+check_bitwise_one(void)
+{
+    unsigned int n_loops;
+    int dst_ofs;
+    int n_bits;
+
+    n_loops = 0;
+    for (n_bits = 0; n_bits <= 64; n_bits++) {
+        for (dst_ofs = 0; dst_ofs < 64 - n_bits; dst_ofs++) {
+            ovs_be64 dst = htonll(random_uint64());
+            ovs_be64 orig_dst = dst;
+            ovs_be64 expect;
+
+            if (n_bits == 64) {
+                expect = htonll(UINT64_MAX);
+            } else {
+                uint64_t mask = (UINT64_C(1) << n_bits) - 1;
+                expect = orig_dst | htonll(mask << dst_ofs);
+            }
+
+            bitwise_one(&dst, sizeof dst, dst_ofs, n_bits);
+            if (expect != dst) {
+                fprintf(stderr,"bitwise_one(0x%016"PRIx64",8,%d, %d) "
+                        "yielded 0x%016"PRIx64" "
+                        "instead of the expected 0x%016"PRIx64"\n",
+                        ntohll(orig_dst), dst_ofs,
+                        n_bits,
+                        ntohll(dst), ntohll(expect));
+                abort();
+            }
+
+            n_loops++;
+        }
+    }
+
+    if (n_loops != 64 * (64 + 1) / 2) {
+        abort();
+    }
+}
+
 int
 main(void)
 {
@@ -170,5 +211,7 @@ main(void)
 
     check_bitwise_zero();
 
+    check_bitwise_one();
+
     return 0;
 }