Re: [tarantool-patches] Re: [PATCH v1 3/4] box: introduce bitmap_majority_test routine

[Kirill Shcherbatov <kshcherbatov@tarantool.org>]

Hi! Ok... Also changed the only place in following patch.

===============================
A new bitmap_size routine returns size of bitmap allocation
aligned by sizeof(unsigned long) words by count of bits to work
with. Memory chunk must be aligned as bit_set/bit_clear
functions use unsigned long words to setup bits.
We need bitmap_size to make an allocation for format:fields to
test compatibility of required fields bitmap with another one
that is built for parsed tuple on tuple_init_field_map.

Needed for #1012
---
 src/lib/bit/bit.h        | 13 +++++++++++++
 test/unit/CMakeLists.txt |  2 +-
 test/unit/bit.c          | 27 +++++++++++++++++++++++++++
 test/unit/bit.result     |  8 ++++++++
 4 files changed, 49 insertions(+), 1 deletion(-)

diff --git a/src/lib/bit/bit.h b/src/lib/bit/bit.h
index 370a0cc5d..04be818b2 100644
--- a/src/lib/bit/bit.h
+++ b/src/lib/bit/bit.h
@@ -238,6 +238,19 @@ bit_clear(void *data, size_t pos)
 	return prev;
 }
 
+/**
+ * Return sizeof(unsigned long)-words aligned size of bitmap by
+ * bit_count - count of bits to set. Size must be aligned, as
+ * bit_sit/bit_clear operations use unsigned long words to setup
+ * bit.
+ */
+static inline size_t
+bitmap_size(size_t bit_count)
+{
+	size_t word_count = DIV_ROUND_UP(bit_count, CHAR_BIT * sizeof(long));
+	return word_count * sizeof(long);
+}
+
 /**
  * @cond false
  * @brief Naive implementation of ctz.
diff --git a/test/unit/CMakeLists.txt b/test/unit/CMakeLists.txt
index 0025d3611..5b2f152e3 100644
--- a/test/unit/CMakeLists.txt
+++ b/test/unit/CMakeLists.txt
@@ -36,7 +36,7 @@ add_executable(rope.test rope.c)
 target_link_libraries(rope.test salad)
 add_executable(int96.test int96.cc)
 add_executable(bit.test bit.c bit.c)
-target_link_libraries(bit.test bit)
+target_link_libraries(bit.test bit unit)
 add_executable(bitset_basic.test bitset_basic.c)
 target_link_libraries(bitset_basic.test bitset)
 add_executable(bitset_iterator.test bitset_iterator.c)
diff --git a/test/unit/bit.c b/test/unit/bit.c
index beb89a7e4..67a7ccd63 100644
--- a/test/unit/bit.c
+++ b/test/unit/bit.c
@@ -206,6 +206,32 @@ test_bit_iter_empty(void)
 	footer();
 }
 
+static void
+test_bitmap(void)
+{
+	header();
+	plan(5);
+
+	size_t rc = bitmap_size(0);
+	is(rc, 0, "empty bitmap: have %zu expected %d", rc, 0);
+	rc = bitmap_size(1);
+	is(rc, sizeof(unsigned long), "1-item bitmap: have %zu expected %lu",
+	   rc, sizeof(unsigned long));
+	rc = bitmap_size(4);
+	is(rc, sizeof(unsigned long), "4-items bitmap: have %zu expected %lu",
+	   rc, sizeof(unsigned long));
+	rc = bitmap_size(CHAR_BIT * sizeof(unsigned long));
+	is(rc, sizeof(unsigned long), "%lu-items bitmap: have %zu expected %lu",
+	   CHAR_BIT * sizeof(unsigned long), rc, sizeof(unsigned long));
+	rc = bitmap_size(CHAR_BIT * sizeof(unsigned long) + 1);
+	is(rc, 2 * sizeof(unsigned long),
+	   "%lu-items bitmap: have %zu expected %lu",
+	   CHAR_BIT * sizeof(unsigned long) + 1, rc, 2 * sizeof(unsigned long));
+
+	check_plan();
+	footer();
+}
+
 int
 main(void)
 {
@@ -216,4 +242,5 @@ main(void)
 	test_index();
 	test_bit_iter();
 	test_bit_iter_empty();
+	test_bitmap();
 }
diff --git a/test/unit/bit.result b/test/unit/bit.result
index e2c5601f3..d99cfbf01 100644
--- a/test/unit/bit.result
+++ b/test/unit/bit.result
@@ -891,3 +891,11 @@ Clear: 0, 1, 2, 4, 5, 6, 7, 8, 10, 12, 13, 14, 15, 19, 20, 21, 23, 26, 28, 30, 3
 	*** test_bit_iter: done ***
 	*** test_bit_iter_empty ***
 	*** test_bit_iter_empty: done ***
+	*** test_bitmap ***
+1..5
+ok 1 - empty bitmap: have 0 expected 0
+ok 2 - 1-item bitmap: have 8 expected 8
+ok 3 - 4-items bitmap: have 8 expected 8
+ok 4 - 64-items bitmap: have 8 expected 8
+ok 5 - 65-items bitmap: have 16 expected 16
+	*** test_bitmap: done ***
-- 
2.19.2