tests: Add unit tests for cg_build_path()

This commit adds unit tests for the internal function
cg_build_path().  While code coverage is not (yet) enabled,
I believe these tests provide full code coverage for the
aforementioned function and its sister function
cg_build_path_locked().

The following tests are in this commit:

BuildPathV1_ControllerMismatch() - Calls cg_build_path() with a
    controller that isn't in cg_mount_table[].  Expects a return
    value of NULL

BuildPathV1_ControllerMatch() - Calls cg_build_path() with a valid
    controller in cg_mount_table[]

BuildPathV1_ControllerMatchWithName() - Calls cg_build_path() with
    a valid controller and a cgroup name

BuildPathV1_ControllerMatchWithNs() - Calls cg_build_path() with a
    valid controller that has a namespace

BuildPathV1_ControllerMatchWithNameAndNs() - Calls cg_build_path()
    with a valid controller, a cgroup name, and the controller has
    a namespace

Signed-off-by: Tom Hromatka <tom.hromatka@oracle.com>
Signed-off-by: Dhaval Giani <dhaval.giani@oracle.com>

diff --git a/tests/gunit/001-path.cpp b/tests/gunit/001-path.cpp
new file mode 100644 (file)
index 0000000..a0e3c86
--- /dev/null
+++ b/tests/gunit/001-path.cpp
@@ -0,0 +1,175 @@
+/**
+ * libcgroup googletest for cg_build_path()
+ *
+ * Copyright (c) 2019 Oracle and/or its affiliates.  All rights reserved.
+ * Author: Tom Hromatka <tom.hromatka@oracle.com>
+ */
+
+/*
+ * This library is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This library is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
+ * for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this library; if not, see <http://www.gnu.org/licenses>.
+ */
+
+#include "gtest/gtest.h"
+
+#include "libcgroup-internal.h"
+
+class BuildPathV1Test : public ::testing::Test {
+       protected:
+
+       /**
+        * Setup this test case
+        *
+        * This test case calls cg_build_path() to generate various
+        * cgroup paths.  The SetUp() routine creates a simple mount
+        * table that can be used to verify cg_build_path() behavior.
+        *
+        * cg_mount_table for this test is as follows:
+        *      name            mount_point                     index
+        *      -----------------------------------------------------
+        *      controller0     /sys/fs/cgroup/controller0      0
+        *      controller1     /sys/fs/cgroup/controller1      1
+        *      controller2     /sys/fs/cgroup/controller2      2
+        *      controller3     /sys/fs/cgroup/controller3      3
+        *      controller4     /sys/fs/cgroup/controller4      4
+        *      controller5     /sys/fs/cgroup/controller5      5
+        *
+        * Note that controllers 1 and 5 are also given namespaces
+        */
+       void SetUp() override {
+               char NAMESPACE1[] = "ns1";
+               char NAMESPACE5[] = "ns5";
+               const int ENTRY_CNT = 6;
+               int i;
+
+               memset(&cg_mount_table, 0, sizeof(cg_mount_table));
+               memset(cg_namespace_table, 0,
+                       CG_CONTROLLER_MAX * sizeof(cg_namespace_table[0]));
+
+               // Populate the mount table
+               for (i = 0; i < ENTRY_CNT; i++) {
+                       snprintf(cg_mount_table[i].name, FILENAME_MAX,
+                                "controller%d", i);
+                       cg_mount_table[i].index = i;
+
+                       snprintf(cg_mount_table[i].mount.path, FILENAME_MAX,
+                                "/sys/fs/cgroup/%s", cg_mount_table[i].name);
+                       cg_mount_table[i].mount.next = NULL;
+               }
+
+               // Give a couple of the entries a namespace as well
+               cg_namespace_table[1] = NAMESPACE1;
+               cg_namespace_table[5] = NAMESPACE5;
+       }
+};
+
+/**
+ * No matching controller test
+ * @param BuildPathV1Test googletest test case name
+ * @param BuildPathV1_ControllerMismatch test name
+ *
+ * This test will walk through the entire controller mount table
+ * and fail to find a match.
+ * https://github.com/libcgroup/libcgroup/blob/62f76650db84c0a25f76ece3a79d9d16a1e9f931/src/api.c#L1300
+ */
+TEST_F(BuildPathV1Test, BuildPathV1_ControllerMismatch)
+{
+       char *name = NULL;
+       char path[FILENAME_MAX];
+       /* type intentionally _does not_ match any controllers */
+       char type[] = "FOO";
+       char *out;
+
+       out = cg_build_path(name, path, type);
+       ASSERT_STREQ(out, NULL);
+}
+
+/**
+ * Matching controller test
+ * @param BuildPathV1Test googletest test case name
+ * @param BuildPathV1_ControllerMatch test name
+ *
+ * This test finds a matching controller in the mount table.  Both the
+ * namespace and the cgroup name are NULL.
+ */
+TEST_F(BuildPathV1Test, BuildPathV1_ControllerMatch)
+{
+       char *name = NULL;
+       char path[FILENAME_MAX];
+       char type[] = "controller0";
+       char *out;
+
+       out = cg_build_path(name, path, type);
+       ASSERT_STREQ(out, "/sys/fs/cgroup/controller0/");
+}
+
+/**
+ * Matching controller test with a cgroup name
+ * @param BuildPathV1Test googletest test case name
+ * @param BuildPathV1_ControllerMatchWithName test name
+ *
+ * This test finds a matching controller in the mount table.  The
+ * namespace is NULL, but a valid cgroup name is provided.  This
+ * exercises the `if (name)` statement
+ * https://github.com/libcgroup/libcgroup/blob/62f76650db84c0a25f76ece3a79d9d16a1e9f931/src/api.c#L1289
+ */
+TEST_F(BuildPathV1Test, BuildPathV1_ControllerMatchWithName)
+{
+       char name[] = "TomsCgroup1";
+       char path[FILENAME_MAX];
+       char type[] = "controller3";
+       char *out;
+
+       out = cg_build_path(name, path, type);
+       ASSERT_STREQ(out, "/sys/fs/cgroup/controller3/TomsCgroup1/");
+}
+
+/**
+ * Matching controller test with a namespace
+ * @param BuildPathV1Test googletest test case name
+ * @param BuildPathV1_ControllerMatchWithNs test name
+ *
+ * This test finds a matching controller in the mount table.  The
+ * namespace is valid, but the cgroup name is NULL.  This exercises
+ * exercises the `if (cg_namespace_table[i])` statement
+ * https://github.com/libcgroup/libcgroup/blob/62f76650db84c0a25f76ece3a79d9d16a1e9f931/src/api.c#L1278
+ */
+TEST_F(BuildPathV1Test, BuildPathV1_ControllerMatchWithNs)
+{
+       char *name = NULL;
+       char path[FILENAME_MAX];
+       char type[] = "controller1";
+       char *out;
+
+       out = cg_build_path(name, path, type);
+       ASSERT_STREQ(out, "/sys/fs/cgroup/controller1/ns1/");
+}
+
+/**
+ * Matching controller test with a namespace and a cgroup name
+ * @param BuildPathV1Test googletest test case name
+ * @param BuildPathV1_ControllerMatchWithNameAndNs test name
+ *
+ * This test finds a matching controller in the mount table.  Both the
+ * namespace and the cgroup name are valid.  This exercises both if
+ * statements in cg_build_path_locked().
+ */
+TEST_F(BuildPathV1Test, BuildPathV1_ControllerMatchWithNameAndNs)
+{
+       char name[] = "TomsCgroup2";
+       char path[FILENAME_MAX];
+       char type[] = "controller5";
+       char *out;
+
+       out = cg_build_path(name, path, type);
+       ASSERT_STREQ(out, "/sys/fs/cgroup/controller5/ns5/TomsCgroup2/");
+}

diff --git a/tests/gunit/Makefile.am b/tests/gunit/Makefile.am
index 3ffeac320b9eaff895111a7986c62d87963be9e8..8bc014c0fd5e0005c5bc56eb49cb9042b9dfdb5f 100644 (file)
--- a/tests/gunit/Makefile.am
+++ b/tests/gunit/Makefile.am
@@ -35,4 +35,5 @@ check_LTLIBRARIES = libgtest.la
 check_PROGRAMS = gtest
 TESTS = gtest
 
-gtest_SOURCES = gtest.cpp
+gtest_SOURCES = gtest.cpp \
+               001-path.cpp