From 5eec94baacc074ff9dd64923792f0efb5e897957 Mon Sep 17 00:00:00 2001
From: Martchus <martchus@gmx.net>
Date: Sat, 9 Jun 2018 19:47:50 +0200
Subject: [PATCH] Make OpenSslRandomDevice usable with uniform_int_distribution

---
 CMakeLists.txt                |  5 ++--
 tests/opensslrandomdevice.cpp | 51 +++++++++++++++++++++++++++++++++++
 util/opensslrandomdevice.cpp  | 27 ++++++++-----------
 util/opensslrandomdevice.h    | 17 ++++++++++++
 4 files changed, 82 insertions(+), 18 deletions(-)
 create mode 100644 tests/opensslrandomdevice.cpp

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 0e96ee9..73e934f 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -25,6 +25,7 @@ set(TEST_HEADER_FILES
 set(TEST_SRC_FILES
     tests/cppunit.cpp
     tests/passwordfiletests.cpp
+    tests/opensslrandomdevice.cpp
 )
 
 set(DOC_FILES
@@ -39,8 +40,8 @@ set(META_APP_AUTHOR "Martchus")
 set(META_APP_URL "https://github.com/${META_APP_AUTHOR}/${META_PROJECT_NAME}")
 set(META_APP_DESCRIPTION "C++ library to read/write passwords from/to encrypted files")
 set(META_VERSION_MAJOR 3)
-set(META_VERSION_MINOR 1)
-set(META_VERSION_PATCH 4)
+set(META_VERSION_MINOR 2)
+set(META_VERSION_PATCH 0)
 set(META_PUBLIC_SHARED_LIB_DEPENDS c++utilities)
 set(META_PUBLIC_STATIC_LIB_DEPENDS c++utilities_static)
 
diff --git a/tests/opensslrandomdevice.cpp b/tests/opensslrandomdevice.cpp
new file mode 100644
index 0000000..a80cd51
--- /dev/null
+++ b/tests/opensslrandomdevice.cpp
@@ -0,0 +1,51 @@
+#include "../util/opensslrandomdevice.h"
+
+#include <c++utilities/tests/testutils.h>
+
+#include <cppunit/TestFixture.h>
+#include <cppunit/extensions/HelperMacros.h>
+
+#include <random>
+
+using namespace std;
+using namespace Util;
+using namespace TestUtilities::Literals;
+
+using namespace CPPUNIT_NS;
+
+/*!
+ * \brief The OpenSslRandomDeviceTests class tests the Util::OpenSslRandomDevice class.
+ */
+class OpenSslRandomDeviceTests : public TestFixture {
+    CPPUNIT_TEST_SUITE(OpenSslRandomDeviceTests);
+    CPPUNIT_TEST(testUsageWithStandardClasses);
+    CPPUNIT_TEST_SUITE_END();
+
+public:
+    void setUp();
+    void tearDown();
+
+    void testUsageWithStandardClasses();
+};
+
+CPPUNIT_TEST_SUITE_REGISTRATION(OpenSslRandomDeviceTests);
+
+void OpenSslRandomDeviceTests::setUp()
+{
+}
+
+void OpenSslRandomDeviceTests::tearDown()
+{
+}
+
+/*!
+ * \brief Tests using the OpenSslRandomDevice with std::uniform_int_distribution.
+ */
+void OpenSslRandomDeviceTests::testUsageWithStandardClasses()
+{
+    uniform_int_distribution<> dist(1, 10);
+    const Util::OpenSslRandomDevice random;
+    const auto val = dist(random);
+    CPPUNIT_ASSERT_GREATEREQUAL(1, val);
+    CPPUNIT_ASSERT_LESSEQUAL(10, val);
+}
diff --git a/util/opensslrandomdevice.cpp b/util/opensslrandomdevice.cpp
index e6d7e2b..77a2844 100644
--- a/util/opensslrandomdevice.cpp
+++ b/util/opensslrandomdevice.cpp
@@ -13,11 +13,6 @@ using namespace std;
 
 namespace Util {
 
-/*!
- * \namespace QtGui
- * \brief Contains all miscellaneous utility functions.
- */
-
 /*!
  * \class OpenSslRandomDevice
  * \brief Provides a random device using the OpenSSL function RAND_bytes().
@@ -38,18 +33,18 @@ uint32 OpenSslRandomDevice::operator()() const
     unsigned char buf[4];
     if (RAND_bytes(buf, sizeof(buf))) {
         return ConversionUtilities::LE::toUInt32(reinterpret_cast<char *>(buf));
-    } else {
-        string msg;
-        unsigned long errorCode = ERR_get_error();
-        while (errorCode != 0) {
-            if (!msg.empty()) {
-                msg += '\n';
-            }
-            msg += ERR_error_string(errorCode, 0);
-            errorCode = ERR_get_error();
-        }
-        throw Io::CryptoException(msg);
     }
+
+    // handle error case
+    string errorMsg;
+    while (unsigned long errorCode = ERR_get_error()) {
+        if (!errorMsg.empty()) {
+            errorMsg += '\n';
+        }
+        errorMsg += ERR_error_string(errorCode, nullptr);
+        errorCode = ERR_get_error();
+    }
+    throw Io::CryptoException(errorMsg);
 }
 
 /*!
diff --git a/util/opensslrandomdevice.h b/util/opensslrandomdevice.h
index afa8ebe..68deef0 100644
--- a/util/opensslrandomdevice.h
+++ b/util/opensslrandomdevice.h
@@ -5,14 +5,31 @@
 
 #include <c++utilities/conversion/types.h>
 
+#include <limits>
+
 namespace Util {
 
 class PASSWORD_FILE_EXPORT OpenSslRandomDevice {
 public:
+    using result_type = uint32;
+
     OpenSslRandomDevice();
     uint32 operator()() const;
     bool status() const;
+    static constexpr result_type min();
+    static constexpr result_type max();
 };
+
+constexpr OpenSslRandomDevice::result_type OpenSslRandomDevice::min()
+{
+    return std::numeric_limits<result_type>::min();
+}
+
+constexpr OpenSslRandomDevice::result_type OpenSslRandomDevice::max()
+{
+    return std::numeric_limits<result_type>::max();
+}
+
 } // namespace Util
 
 #endif // OPENSSLRANDOMDEVICE_H