flags: Add raft_flags methods.

flags will be used to track node capabilities.

Signed-off-by: Mathieu Borderé <[email protected]>

Makefile.am

@@ -21,6 +21,7 @@ libraft_la_SOURCES = \
   src/election.c \
   src/entry.c \
   src/err.c \
+  src/flags.c \
   src/heap.c \
   src/lifecycle.c \
   src/log.c \
@@ -65,13 +66,15 @@ test_unit_core_SOURCES = \
   src/compress.c \
   src/configuration.c \
   src/err.c \
+  src/flags.c \
   src/heap.c \
   src/log.c \
   test/unit/main_core.c \
   test/unit/test_byte.c \
   test/unit/test_compress.c \
   test/unit/test_configuration.c \
   test/unit/test_err.c \
+  test/unit/test_flags.c \
   test/unit/test_log.c \
   test/unit/test_queue.c
 test_unit_core_CFLAGS = $(AM_CFLAGS) -Wno-conversion

include/raft.h

@@ -79,6 +79,11 @@ typedef unsigned long long raft_index;
  */
 typedef unsigned long long raft_time;
 
+/**
+ * Hold the features a raft node is capable of.
+ */
+typedef uint64_t raft_flags;
+
 /**
  * A data buffer.
  */

src/flags.c

@@ -0,0 +1,16 @@
+#include "flags.h"
+
+inline raft_flags flagsSet(raft_flags in, raft_flags flags)
+{
+    return in | flags;
+}
+
+inline raft_flags flagsClear(raft_flags in, raft_flags flags)
+{
+    return in & (~flags);
+}
+
+inline bool flagsIsSet(raft_flags in, raft_flags flag)
+{
+    return (bool)(in & flag);
+}

src/flags.h

@@ -0,0 +1,20 @@
+#ifndef FLAGS_H_
+#define FLAGS_H_
+
+#include "../include/raft.h"
+
+#define RAFT_DEFAULT_FEATURE_FLAGS (0)
+
+/* Adds the flags @flags to @in and returns the new flags. Multiple flags should
+ * be combined using the `|` operator. */
+raft_flags flagsSet(raft_flags in, raft_flags flags);
+
+/* Clears the flags @flags from @in and returns the new flags. Multiple flags
+ * should be combined using the `|` operator. */
+raft_flags flagsClear(raft_flags in, raft_flags flags);
+
+/* Returns `true` if the single flag @flag is set in @in, otherwise returns
+ * `false`. */
+bool flagsIsSet(raft_flags in, raft_flags flag);
+
+#endif /* FLAGS_H */

test/unit/test_flags.c

@@ -0,0 +1,97 @@
+#include "../../src/flags.h"
+#include "../lib/runner.h"
+
+/******************************************************************************
+ *
+ * flags
+ *
+ *****************************************************************************/
+
+SUITE(flags)
+
+TEST(flags, empty, NULL, NULL, 0, NULL)
+{
+    raft_flags flags = 0;
+    for (int i = 0; i < 64; i++) {
+        munit_assert_false(flagsIsSet(flags, ((raft_flags)1) << i));
+    }
+    return MUNIT_OK;
+}
+
+TEST(flags, setClear, NULL, NULL, 0, NULL)
+{
+    raft_flags flags = 0;
+    raft_flags flag = 0;
+    for (int i = 0; i < 64; i++) {
+        flag = ((raft_flags)1) << i;
+        flags = flagsSet(flags, flag);
+        munit_assert_true(flagsIsSet(flags, flag));
+        flags = flagsClear(flags, flag);
+        munit_assert_false(flagsIsSet(flags, flag));
+        munit_assert_true(flags == 0);
+    }
+    return MUNIT_OK;
+}
+
+TEST(flags, setMultipleClearMultiple, NULL, NULL, 0, NULL)
+{
+    raft_flags in = 0;
+    raft_flags out;
+    raft_flags flags = (raft_flags)(1 | 1 << 4 | 1 << 13 | (raft_flags)1 << 40 |
+                                    (raft_flags)1 << 63);
+    out = flagsSet(in, flags);
+    /* clang-format off */
+    int positions[64] = {
+        1, 0, 0, 0, 1, 0, 0, 0, // 0th and 4th
+        0, 0, 0, 0, 0, 1, 0, 0, // 13th
+        0, 0, 0, 0, 0, 0, 0, 0,
+        0, 0, 0, 0, 0, 0, 0, 0,
+        0, 0, 0, 0, 0, 0, 0, 0,
+        1, 0, 0, 0, 0, 0, 0, 0, // 40th
+        0, 0, 0, 0, 0, 0, 0, 0,
+        0, 0, 0, 0, 0, 0, 0, 1, // 63th
+    };
+    /* clang-format on */
+    for (unsigned i = 0; i < 64; i++) {
+        if (positions[i]) {
+            munit_assert_true(flagsIsSet(out, (raft_flags)1 << i));
+        } else {
+            munit_assert_false(flagsIsSet(out, (raft_flags)1 << i));
+        }
+    }
+    out = flagsClear(out, flags);
+    munit_assert_true(out == 0);
+    return MUNIT_OK;
+}
+
+TEST(flags, setMultipleClearSingle, NULL, NULL, 0, NULL)
+{
+    raft_flags in = 0;
+    raft_flags out;
+    raft_flags flags = (raft_flags)(1 << 3 | 1 << 5 | 1 << 18 |
+                                    (raft_flags)1 << 32 | (raft_flags)1 << 35);
+    out = flagsSet(in, flags);
+    /* clang-format off */
+    int positions[64] = {
+        0, 0, 0, 1, 0, 1, 0, 0, // 3rd and 5th
+        0, 0, 0, 0, 0, 0, 0, 0,
+        0, 0, 1, 0, 0, 0, 0, 0, // 18th
+        0, 0, 0, 0, 0, 0, 0, 0,
+        1, 0, 0, 1, 0, 0, 0, 0, // 32rd 35th
+        0, 0, 0, 0, 0, 0, 0, 0,
+        0, 0, 0, 0, 0, 0, 0, 0,
+        0, 0, 0, 0, 0, 0, 0, 0,
+    };
+    /* clang-format on */
+    for (unsigned i = 0; i < 64; i++) {
+        if (positions[i]) {
+            munit_assert_true(flagsIsSet(out, (raft_flags)1 << i));
+        } else {
+            munit_assert_false(flagsIsSet(out, (raft_flags)1 << i));
+        }
+    }
+    out = flagsClear(out, (raft_flags)1 << 32);
+    munit_assert_true(
+        out == (raft_flags)(1 << 3 | 1 << 5 | 1 << 18 | (raft_flags)1 << 35));
+    return MUNIT_OK;
+}