[1704] Add proper testcases for the file based locker

src/lib/util/tests/Makefile.am

@@ -7,6 +7,7 @@ AM_CPPFLAGS += -DTEST_DATA_BUILDDIR=\"$(abs_builddir)\"
 # used to bind a UNIX domain socket so we can minimize the risk of exceeding
 # the limit of file name path size.
 AM_CPPFLAGS += -DTEST_DATA_TOPBUILDDIR=\"$(abs_top_builddir)\"
+AM_CPPFLAGS += -DTOP_SRCDIR=\"${abs_top_srcdir}\"
 AM_CXXFLAGS = $(B10_CXXFLAGS)
 
 if USE_STATIC_LINK
@@ -28,6 +29,7 @@ run_unittests_SOURCES += filename_unittest.cc
 run_unittests_SOURCES += hex_unittest.cc
 run_unittests_SOURCES += io_utilities_unittest.cc
 run_unittests_SOURCES += lru_list_unittest.cc
+run_unittests_SOURCES += interprocess_sync_file_unittest.cc
 run_unittests_SOURCES += qid_gen_unittest.cc
 run_unittests_SOURCES += random_number_generator_unittest.cc
 run_unittests_SOURCES += sha1_unittest.cc

src/lib/util/tests/interprocess_sync_file_unittest.cc

@@ -0,0 +1,161 @@
+// Copyright (C) 2012  Internet Systems Consortium, Inc. ("ISC")
+//
+// Permission to use, copy, modify, and/or distribute this software for any
+// purpose with or without fee is hereby granted, provided that the above
+// copyright notice and this permission notice appear in all copies.
+//
+// THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+// REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+// AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+// INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+// LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+// OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+// PERFORMANCE OF THIS SOFTWARE.
+
+#include "util/interprocess_sync_file.h"
+#include <gtest/gtest.h>
+
+using namespace std;
+
+namespace isc {
+namespace util {
+
+class InterprocessSyncFileTest : public ::testing::Test {
+protected:
+    InterprocessSyncFileTest() {}
+};
+
+TEST_F(InterprocessSyncFileTest, TestLock) {
+  InterprocessSync *sync = new InterprocessSyncFile("test");
+  InterprocessSyncLocker *locker = sync->getLocker();
+
+  EXPECT_TRUE(locker->lock());
+
+  int fds[2];
+
+  // Here, we check that a lock has been taken by forking and
+  // checking from the child that a lock exists. This has to be
+  // done from a separate process as we test by trying to lock the
+  // range again on the lock file. The lock attempt would pass if
+  // done from the same process for the granted range. The lock
+  // attempt must fail to pass our check.
+
+  bool was_locked(false);
+
+  pipe(fds);
+
+  if (fork() == 0) {
+      unsigned char locked = 0;
+      // Child writes to pipe
+      close(fds[0]);
+
+      InterprocessSync *sync2 = new InterprocessSyncFile("test");
+      InterprocessSyncLocker *locker2 = sync2->getLocker();
+
+      if (!locker2->tryLock()) {
+          locked = 1;
+      }
+
+      delete locker2;
+      delete sync2;
+
+      write(fds[1], &locked, sizeof locked);
+      close(fds[1]);
+      exit(0);
+  } else {
+      unsigned char locked = 0;
+      // Parent reads from pipe
+      close(fds[1]);
+
+      // Read status and set flag
+      read(fds[0], &locked, sizeof locked);
+      if (locked == 1) {
+        was_locked = true;
+      } else {
+        was_locked = false;
+      }
+
+      close(fds[0]);
+  }
+
+  EXPECT_TRUE(was_locked);
+  EXPECT_TRUE(locker->unlock());
+
+  delete locker;
+  delete sync;
+}
+
+TEST_F(InterprocessSyncFileTest, TestMultipleFilesDirect) {
+  InterprocessSync *sync = new InterprocessSyncFile("test1");
+  InterprocessSyncLocker *locker = sync->getLocker();
+
+  EXPECT_TRUE(locker->lock());
+
+  InterprocessSync *sync2 = new InterprocessSyncFile("test2");
+  InterprocessSyncLocker *locker2 = sync2->getLocker();
+  EXPECT_TRUE(locker2->lock());
+  EXPECT_TRUE(locker2->unlock());
+  delete sync2;
+  delete locker2;
+
+  EXPECT_TRUE(locker->unlock());
+
+  delete locker;
+  delete sync;
+}
+
+TEST_F(InterprocessSyncFileTest, TestMultipleFilesForked) {
+  InterprocessSync *sync = new InterprocessSyncFile("test");
+  InterprocessSyncLocker *locker = sync->getLocker();
+
+  EXPECT_TRUE(locker->lock());
+
+  int fds[2];
+
+  bool was_not_locked(true);
+
+  pipe(fds);
+
+  if (fork() == 0) {
+      unsigned char locked = 0xff;
+      // Child writes to pipe
+      close(fds[0]);
+
+      InterprocessSync *sync2 = new InterprocessSyncFile("test2");
+      InterprocessSyncLocker *locker2 = sync2->getLocker();
+
+      if (locker2->tryLock()) {
+          locked = 0;
+      }
+
+      delete locker2;
+      delete sync2;
+
+      write(fds[1], &locked, sizeof locked);
+      close(fds[1]);
+      exit(0);
+  } else {
+      unsigned char locked = 0xff;
+      // Parent reads from pipe
+      close(fds[1]);
+
+      // Read status and set flag
+      read(fds[0], &locked, sizeof locked);
+      if (locked == 0) {
+        was_not_locked = true;
+      } else {
+        was_not_locked = false;
+      }
+
+      close(fds[0]);
+  }
+
+  EXPECT_TRUE(was_not_locked);
+  EXPECT_TRUE(locker->unlock());
+
+  delete locker;
+  delete sync;
+}
+
+} // namespace util
+} // namespace isc

src/lib/util/tests/run_unittests.cc

@@ -14,10 +14,12 @@
 
 #include <gtest/gtest.h>
 #include <util/unittests/run_all.h>
+#include <stdlib.h>
 
 int
 main(int argc, char* argv[]) {
     ::testing::InitGoogleTest(&argc, argv);
 
+    setenv("B10_FROM_SOURCE", TOP_SRCDIR, 1);
     return (isc::util::unittests::run_all());
 }