Allow zero-valued InstanceHandle_t [12942]

include/fastdds/rtps/common/InstanceHandle.h

@@ -19,6 +19,8 @@
 #ifndef _FASTDDS_RTPS_INSTANCEHANDLE_H_
 #define _FASTDDS_RTPS_INSTANCEHANDLE_H_
 
+#include <array>
+
 #include <fastrtps/fastrtps_dll.h>
 #include <fastdds/rtps/common/Types.h>
 #include <fastdds/rtps/common/Guid.h>
@@ -27,101 +29,164 @@ namespace eprosima {
 namespace fastrtps {
 namespace rtps {
 
+using KeyHash_t = std::array<octet, 16>;
+
+struct RTPS_DllAPI InstanceHandleValue_t
+{
+    /**
+     * Write access indexing operator.
+     *
+     * Provides a reference to the byte value at position @c i.
+     *
+     * @param [in] i index of the byte to return.
+     *
+     * @post Method has_been_set() returns @c true.
+     *
+     * @remark Do not use this method to check if this value has been set.
+     *         Use method has_been_set() instead.
+     */
+    octet& operator [] (
+            size_t i) noexcept
+    {
+        has_been_set_ = true;
+        return value_[i];
+    }
+
+    /**
+     * Read access indexing operator.
+     *
+     * Provides the byte value at position @c i.
+     *
+     * @param [in] i index of the byte to return.
+     *
+     * @remark Do not use this method to check if this value has been set.
+     *         Use method has_been_set() instead.
+     */
+    octet operator [] (
+            size_t i) const noexcept
+    {
+        return value_[i];
+    }
+
+    /**
+     * Write access pointer cast operator.
+     *
+     * Provides a pointer to the start of the raw data.
+     *
+     * @post Method has_been_set() returns @c true.
+     *
+     * @remark Do not use this method to check if this value has been set.
+     *         Use method has_been_set() instead.
+     */
+    operator octet* () noexcept
+    {
+        has_been_set_ = true;
+        return value_.data();
+    }
+
+    /**
+     * Read access pointer cast operator.
+     *
+     * Provides a pointer to the start of the raw data.
+     *
+     * @remark Do not use this method to check if this value has been set.
+     *         Use method has_been_set() instead.
+     */
+    operator const octet* () const noexcept
+    {
+        return value_.data();
+    }
+
+    /**
+     * Return whether any of the write access operators of this value has been used.
+     */
+    bool has_been_set() const noexcept
+    {
+        return has_been_set_;
+    }
+
+    /**
+     * Equality comparison operator.
+     */
+    bool operator == (
+            const InstanceHandleValue_t& other) const noexcept
+    {
+        return (has_been_set_ == other.has_been_set_) && (value_ == other.value_);
+    }
+
+    /**
+     * Less than comparisor operator.
+     */
+    bool operator < (
+            const InstanceHandleValue_t& other) const noexcept
+    {
+        if (has_been_set_)
+        {
+            return other.has_been_set_ && value_ < other.value_;
+        }
+
+        return other.has_been_set_;
+    }
+
+private:
+
+    //! Hash value
+    KeyHash_t value_ {};
+    //! Flag indicating if value_ has been modified since the creation of this object
+    bool has_been_set_ = false;
+};
+
 /**
  * Struct InstanceHandle_t, used to contain the key for WITH_KEY topics.
  * @ingroup COMMON_MODULE
  */
 struct RTPS_DllAPI InstanceHandle_t
 {
     //!Value
-    octet value[16];
-    InstanceHandle_t()
-    {
-        for (uint8_t i = 0; i < 16; i++)
-        {
-            value[i] = 0;
-        }
-    }
+    InstanceHandleValue_t value;
+
+    InstanceHandle_t() noexcept = default;
 
     InstanceHandle_t(
-            const InstanceHandle_t& ihandle)
-    {
-        for (uint8_t i = 0; i < 16; i++)
-        {
-            value[i] = ihandle.value[i];
-        }
-    }
+            const InstanceHandle_t& ihandle) noexcept = default;
 
     InstanceHandle_t(
-            const GUID_t& guid)
+            const GUID_t& guid) noexcept
     {
-        for (uint8_t i = 0; i < 16; ++i)
-        {
-            if (i < 12)
-            {
-                value[i] = guid.guidPrefix.value[i];
-            }
-            else
-            {
-                value[i] = guid.entityId.value[i - 12];
-            }
-        }
+        *this = guid;
     }
 
     /**
      * Assignment operator
      * @param ihandle Instance handle to copy the data from
      */
     InstanceHandle_t& operator =(
-            const InstanceHandle_t& ihandle)
-    {
-
-        for (uint8_t i = 0; i < 16; i++)
-        {
-            value[i] = ihandle.value[i];
-        }
-        return *this;
-    }
+            const InstanceHandle_t& ihandle) noexcept = default;
 
     /**
      * Assignment operator
      * @param guid GUID to copy the data from
      */
     InstanceHandle_t& operator =(
-            const GUID_t& guid)
+            const GUID_t& guid) noexcept
     {
-        for (uint8_t i = 0; i < 16; i++)
-        {
-            if (i < 12)
-            {
-                value[i] = guid.guidPrefix.value[i];
-            }
-            else
-            {
-                value[i] = guid.entityId.value[i - 12];
-            }
-        }
+        octet* dst = value;
+        memcpy(dst, guid.guidPrefix.value, 12);
+        memcpy(&dst[12], guid.entityId.value, 4);
         return *this;
     }
 
     /**
      * Know if the instance handle is defined
      * @return True if the values are not zero.
      */
-    bool isDefined() const
+    bool isDefined() const noexcept
     {
-        for (uint8_t i = 0; i < 16; ++i)
-        {
-            if (value[i] != 0)
-            {
-                return true;
-            }
-        }
-        return false;
+        return value.has_been_set();
     }
 
     // TODO Review this conversion once InstanceHandle_t is implemented as DDS standard defines
-    explicit operator const GUID_t&() const
+    explicit operator const GUID_t&() const noexcept
     {
         return *reinterpret_cast<const GUID_t*>(this);
     }
@@ -140,21 +205,14 @@ const InstanceHandle_t c_InstanceHandle_Unknown;
  */
 inline bool operator ==(
         const InstanceHandle_t& ihandle1,
-        const InstanceHandle_t& ihandle2)
+        const InstanceHandle_t& ihandle2) noexcept
 {
-    for (uint8_t i = 0; i < 16; ++i)
-    {
-        if (ihandle1.value[i] != ihandle2.value[i])
-        {
-            return false;
-        }
-    }
-    return true;
+    return ihandle1.value == ihandle2.value;
 }
 
 inline bool operator !=(
         const InstanceHandle_t& ihandle1,
-        const InstanceHandle_t& ihandle2)
+        const InstanceHandle_t& ihandle2) noexcept
 {
     return !(ihandle1 == ihandle2);
 }
@@ -168,20 +226,11 @@ inline bool operator !=(
  */
 inline void iHandle2GUID(
         GUID_t& guid,
-        const InstanceHandle_t& ihandle)
+        const InstanceHandle_t& ihandle) noexcept
 {
-    for (uint8_t i = 0; i < 16; ++i)
-    {
-        if (i < 12)
-        {
-            guid.guidPrefix.value[i] = ihandle.value[i];
-        }
-        else
-        {
-            guid.entityId.value[i - 12] = ihandle.value[i];
-        }
-    }
-    return;
+    const octet* value = ihandle.value;
+    memcpy(guid.guidPrefix.value, value, 12);
+    memcpy(guid.entityId.value, &value[12], 4);
 }
 
 /**
@@ -190,28 +239,18 @@ inline void iHandle2GUID(
  * @return GUID_t
  */
 inline GUID_t iHandle2GUID(
-        const InstanceHandle_t& ihandle)
+        const InstanceHandle_t& ihandle) noexcept
 {
     GUID_t guid;
-    for (uint8_t i = 0; i < 16; ++i)
-    {
-        if (i < 12)
-        {
-            guid.guidPrefix.value[i] = ihandle.value[i];
-        }
-        else
-        {
-            guid.entityId.value[i - 12] = ihandle.value[i];
-        }
-    }
+    iHandle2GUID(guid, ihandle);
     return guid;
 }
 
 inline bool operator <(
         const InstanceHandle_t& h1,
-        const InstanceHandle_t& h2)
+        const InstanceHandle_t& h2) noexcept
 {
-    return memcmp(h1.value, h2.value, 16) < 0;
+    return h1.value < h2.value;
 }
 
 #ifndef DOXYGEN_SHOULD_SKIP_THIS_PUBLIC

test/unittest/dds/subscriber/DataReaderTests.cpp

@@ -151,7 +151,7 @@ class DataReaderTests : public ::testing::Test
     {
         FooType data;
 
-        data.index(1);
+        data.index(0);
         type_.get_key(&data, &handle_ok_);
 
         data.index(2);
@@ -512,7 +512,7 @@ class DataReaderTests : public ::testing::Test
 
         // Send data
         DataType data;
-        data.index(1);
+        data.index(0);
         EXPECT_EQ(ReturnCode_t::RETCODE_OK, data_writer_->write(&data, HANDLE_NIL));
 
         // Wait for data to arrive and check OK should be returned
@@ -883,7 +883,7 @@ TEST_F(DataReaderTests, return_loan)
     EXPECT_EQ(ok_code, reader2->enable());
 
     FooType data;
-    data.index(1);
+    data.index(0);
 
     // Send a bunch of samples
     for (int32_t i = 0; i < num_samples; ++i)
@@ -1030,7 +1030,7 @@ TEST_F(DataReaderTests, resource_limits)
     create_entities(nullptr, reader_qos, SUBSCRIBER_QOS_DEFAULT, writer_qos);
 
     FooType data;
-    data.index(1);
+    data.index(0);
 
     // Send a bunch of samples
     for (int32_t i = 0; i < num_samples; ++i)
@@ -1232,7 +1232,7 @@ TEST_F(DataReaderTests, read_unread)
     create_entities(nullptr, reader_qos, SUBSCRIBER_QOS_DEFAULT, writer_qos);
 
     FooType data;
-    data.index(1);
+    data.index(0);
     data.message()[1] = '\0';
 
     // Send a bunch of samples
@@ -1527,7 +1527,7 @@ TEST_F(DataReaderTests, Deserialization_errors)
     create_entities(nullptr, reader_qos, SUBSCRIBER_QOS_DEFAULT, writer_qos);
 
     FooType data;
-    data.index(1);
+    data.index(0);
     data.message()[1] = '\0';
 
     // Check deserialization errors without loans
@@ -1780,7 +1780,7 @@ TEST_F(DataReaderTests, check_key_history_wholesomeness_on_unmatch)
     FooType sample;
     std::array<char, 256> msg = {"checking robustness"};
 
-    sample.index(1);
+    sample.index(0);
     sample.message(msg);
 
     ASSERT_TRUE(data_writer_->write(&sample));
@@ -2053,7 +2053,7 @@ TEST_F(DataReaderTests, read_samples_with_future_changes)
     std::this_thread::sleep_for(std::chrono::milliseconds(100)); // Wait discovery
 
     FooType data;
-    data.index(1);
+    data.index(0);
     data.message()[0] = '\0';
     data.message()[1] = '\0';