[ThreadSafety] Extending lock model with lock_quard.

Reviewed By: jberdine

Differential Revision: D5217177

fbshipit-source-id: b7992a0

infer/src/checkers/ThreadSafety.ml

@@ -83,8 +83,9 @@ module TransferFunctions (CFG : ProcCfg.S) = struct
     | _ -> false
 
   let get_lock_model =
-    let is_std_mutex_lock =
-      let matcher = QualifiedCppName.Match.of_fuzzy_qual_names ["std::mutex::lock"] in
+    let is_cpp_lock =
+      let matcher = QualifiedCppName.Match.of_fuzzy_qual_names [
+          "std::mutex::lock"; "std::lock_guard::lock_guard"] in
       fun pname ->
         QualifiedCppName.Match.match_qualifiers matcher (Typ.Procname.get_qualifiers pname)
     and is_std_mutex_unlock =
@@ -123,7 +124,7 @@ module TransferFunctions (CFG : ProcCfg.S) = struct
             | _ ->
                 NoEffect
           end
-    | (Typ.Procname.ObjC_Cpp _ as pname) when is_std_mutex_lock pname ->
+    | (Typ.Procname.ObjC_Cpp _ as pname) when is_cpp_lock pname ->
         Lock
     | (Typ.Procname.ObjC_Cpp _ as pname) when is_std_mutex_unlock pname ->
         Unlock

infer/tests/codetoanalyze/cpp/threadsafety/issues.exp

@@ -3,3 +3,8 @@ codetoanalyze/cpp/threadsafety/basics.cpp, basics::Basic_get3, 0, THREAD_SAFETY_
 codetoanalyze/cpp/threadsafety/basics.cpp, basics::Basic_get4, 0, THREAD_SAFETY_VIOLATION, [<Beginning of read trace>,access to `suspiciously_read`,<Beginning of write trace>,access to `suspiciously_read`]
 codetoanalyze/cpp/threadsafety/basics_with_mutex.cpp, basics::BasicsWithHeader_get1, 0, THREAD_SAFETY_VIOLATION, [<Beginning of read trace>,access to `field_1`,<Beginning of write trace>,access to `field_1`]
 codetoanalyze/cpp/threadsafety/basics_with_mutex.cpp, basics::BasicsWithHeader_get2, 0, THREAD_SAFETY_VIOLATION, [<Beginning of read trace>,access to `field_2`,<Beginning of write trace>,access to `field_2`]
+codetoanalyze/cpp/threadsafety/lock_guard.cpp, basics::LockGuard_get2, 3, THREAD_SAFETY_VIOLATION, [<Beginning of read trace>,access to `suspiciously_written`,<Beginning of write trace>,access to `suspiciously_written`]
+codetoanalyze/cpp/threadsafety/lock_guard.cpp, basics::LockGuard_get3, 0, THREAD_SAFETY_VIOLATION, [<Beginning of read trace>,access to `not_guarded`,<Beginning of write trace>,access to `not_guarded`]
+codetoanalyze/cpp/threadsafety/lock_guard.cpp, basics::LockGuard_get4, 0, THREAD_SAFETY_VIOLATION, [<Beginning of read trace>,access to `suspiciously_read`,<Beginning of write trace>,access to `suspiciously_read`]
+codetoanalyze/cpp/threadsafety/lock_guard_with_scope.cpp, basics::LockGuardWithScope_get3, 0, THREAD_SAFETY_VIOLATION, [<Beginning of read trace>,access to `not_guarded`,<Beginning of write trace>,access to `not_guarded`]
+codetoanalyze/cpp/threadsafety/lock_guard_with_scope.cpp, basics::LockGuardWithScope_get4, 0, THREAD_SAFETY_VIOLATION, [<Beginning of read trace>,access to `suspiciously_read`,<Beginning of write trace>,access to `suspiciously_read`]

infer/tests/codetoanalyze/cpp/threadsafety/lock_guard.cpp

@@ -0,0 +1,51 @@
+/*
+ * Copyright (c) 2017 - present Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+#include <mutex>
+
+namespace basics {
+
+class LockGuard {
+ public:
+  LockGuard() {}
+
+  void set(int new_value) {
+    not_guarded = new_value;
+    suspiciously_written = new_value;
+    std::lock_guard<std::mutex> lock(mutex_);
+    well_guarded = new_value;
+    suspiciously_read = new_value;
+  }
+
+  int get1() {
+    int result;
+    std::lock_guard<std::mutex> lock(mutex_);
+    result = well_guarded;
+    return result;
+  }
+
+  int get2() {
+    int result;
+    std::lock_guard<std::mutex> lock(mutex_);
+    result = suspiciously_written;
+    return result;
+  }
+
+  int get3() { return not_guarded; }
+
+  int get4() { return suspiciously_read; }
+
+ private:
+  int well_guarded;
+  int suspiciously_read;
+  int suspiciously_written;
+  int not_guarded;
+  std::mutex mutex_;
+};
+}

infer/tests/codetoanalyze/cpp/threadsafety/lock_guard_with_scope.cpp

@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 2017 - present Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+#include <mutex>
+
+namespace basics {
+
+class LockGuardWithScope {
+ public:
+  LockGuardWithScope() {}
+
+  void set(int new_value) {
+    {
+      std::lock_guard<std::mutex> lock(mutex_);
+      well_guarded = new_value;
+      suspiciously_read = new_value;
+    }
+
+    // FIXME: missing unlocks in destructors make the following accesses
+    // to be treated as protected
+    not_guarded = new_value;
+    suspiciously_written = new_value;
+  }
+
+  int get1() {
+    int result;
+    std::lock_guard<std::mutex> lock(mutex_);
+    result = well_guarded;
+    return result;
+  }
+
+  int get2() {
+    int result;
+    std::lock_guard<std::mutex> lock(mutex_);
+    // FIXME: It does not report due to missing unlocks in destructors
+    result = suspiciously_written;
+    return result;
+  }
+
+  // FIXME: It reports due to missing unlocks in destructors
+  int get3() { return not_guarded; }
+
+  int get4() { return suspiciously_read; }
+
+ private:
+  int well_guarded;
+  int suspiciously_read;
+  int suspiciously_written;
+  int not_guarded;
+  std::mutex mutex_;
+};
+}