Author: gsim
Date: Thu Jul 19 03:59:58 2007
New Revision: 557570
URL: http://svn.apache.org/viewvc?view=rev&rev=557570
Log:
Added difference operator to the sequence number
Modified:
incubator/qpid/trunk/qpid/cpp/src/qpid/framing/SequenceNumber.cpp
incubator/qpid/trunk/qpid/cpp/src/qpid/framing/SequenceNumber.h
incubator/qpid/trunk/qpid/cpp/src/tests/SequenceNumberTest.cpp
Modified: incubator/qpid/trunk/qpid/cpp/src/qpid/framing/SequenceNumber.cpp
URL:
http://svn.apache.org/viewvc/incubator/qpid/trunk/qpid/cpp/src/qpid/framing/SequenceNumber.cpp?view=diff&rev=557570&r1=557569&r2=557570
==============================================================================
--- incubator/qpid/trunk/qpid/cpp/src/qpid/framing/SequenceNumber.cpp (original)
+++ incubator/qpid/trunk/qpid/cpp/src/qpid/framing/SequenceNumber.cpp Thu Jul
19 03:59:58 2007
@@ -60,3 +60,14 @@
{
return other < *this;
}
+
+namespace qpid {
+namespace framing {
+
+int32_t operator-(const SequenceNumber& a, const SequenceNumber& b)
+{
+ int32_t result = a.value - b.value;
+ return result;
+}
+
+}}
Modified: incubator/qpid/trunk/qpid/cpp/src/qpid/framing/SequenceNumber.h
URL:
http://svn.apache.org/viewvc/incubator/qpid/trunk/qpid/cpp/src/qpid/framing/SequenceNumber.h?view=diff&rev=557570&r1=557569&r2=557570
==============================================================================
--- incubator/qpid/trunk/qpid/cpp/src/qpid/framing/SequenceNumber.h (original)
+++ incubator/qpid/trunk/qpid/cpp/src/qpid/framing/SequenceNumber.h Thu Jul 19
03:59:58 2007
@@ -32,6 +32,7 @@
class SequenceNumber
{
int32_t value;
+
public:
SequenceNumber();
SequenceNumber(uint32_t v);
@@ -43,6 +44,8 @@
bool operator<(const SequenceNumber& other) const;
bool operator>(const SequenceNumber& other) const;
uint32_t getValue() const { return (uint32_t) value; }
+
+ friend int32_t operator-(const SequenceNumber& a, const SequenceNumber& b);
};
}} // namespace qpid::framing
Modified: incubator/qpid/trunk/qpid/cpp/src/tests/SequenceNumberTest.cpp
URL:
http://svn.apache.org/viewvc/incubator/qpid/trunk/qpid/cpp/src/tests/SequenceNumberTest.cpp?view=diff&rev=557570&r1=557569&r2=557570
==============================================================================
--- incubator/qpid/trunk/qpid/cpp/src/tests/SequenceNumberTest.cpp (original)
+++ incubator/qpid/trunk/qpid/cpp/src/tests/SequenceNumberTest.cpp Thu Jul 19
03:59:58 2007
@@ -31,6 +31,9 @@
CPPUNIT_TEST(testIncrementPostfix);
CPPUNIT_TEST(testIncrementPrefix);
CPPUNIT_TEST(testWrapAround);
+ CPPUNIT_TEST(testDifference);
+ CPPUNIT_TEST(testDifferenceWithWrapAround1);
+ CPPUNIT_TEST(testDifferenceWithWrapAround2);
CPPUNIT_TEST_SUITE_END();
public:
@@ -83,23 +86,84 @@
const uint32_t max = 0xFFFFFFFF;
SequenceNumber a(max - 10);
SequenceNumber b(max - 5);
+ checkComparison(a, b, 5);
+ const uint32_t max_signed = 0x7FFFFFFF;
+ SequenceNumber c(max_signed - 10);
+ SequenceNumber d(max_signed - 5);
+ checkComparison(c, d, 5);
+ }
+
+ void checkComparison(SequenceNumber& a, SequenceNumber& b, int gap)
+ {
//increment until b wraps around
- for (int i = 0; i < 6; i++) {
+ for (int i = 0; i < (gap + 2); i++) {
CPPUNIT_ASSERT(++a < ++b);//test prefix
}
- //verify we have wrapped around
- CPPUNIT_ASSERT(a.getValue() > b.getValue());
//keep incrementing until a also wraps around
- for (int i = 0; i < 6; i++) {
+ for (int i = 0; i < (gap + 2); i++) {
CPPUNIT_ASSERT(a++ < b++);//test postfix
}
//let a 'catch up'
- for (int i = 0; i < 5; i++) {
+ for (int i = 0; i < gap; i++) {
a++;
}
CPPUNIT_ASSERT(a == b);
CPPUNIT_ASSERT(++a > b);
+ }
+
+ void testDifference()
+ {
+ SequenceNumber a;
+ SequenceNumber b;
+
+ for (int i = 0; i < 10; i++, ++a) {
+ CPPUNIT_ASSERT_EQUAL(i, a - b);
+ CPPUNIT_ASSERT_EQUAL(-i, b - a);
+ }
+
+ b = a;
+
+ for (int i = 0; i < 10; i++, ++b) {
+ CPPUNIT_ASSERT_EQUAL(-i, a - b);
+ CPPUNIT_ASSERT_EQUAL(i, b - a);
+ }
+ }
+
+ void testDifferenceWithWrapAround1()
+ {
+ const uint32_t max = 0xFFFFFFFF;
+ SequenceNumber a(max - 5);
+ SequenceNumber b(max - 10);
+ checkDifference(a, b, 5);
+ }
+
+ void testDifferenceWithWrapAround2()
+ {
+ const uint32_t max_signed = 0x7FFFFFFF;
+ SequenceNumber c(max_signed - 5);
+ SequenceNumber d(max_signed - 10);
+ checkDifference(c, d, 5);
+ }
+
+ void checkDifference(SequenceNumber& a, SequenceNumber& b, int gap)
+ {
+ CPPUNIT_ASSERT_EQUAL(gap, a - b);
+ CPPUNIT_ASSERT_EQUAL(-gap, b - a);
+
+ //increment until b wraps around
+ for (int i = 0; i < (gap + 2); i++, ++a, ++b) {
+ CPPUNIT_ASSERT_EQUAL(gap, a - b);
+ }
+ //keep incrementing until a also wraps around
+ for (int i = 0; i < (gap + 2); i++, ++a, ++b) {
+ CPPUNIT_ASSERT_EQUAL(gap, a - b);
+ }
+ //let b catch up and overtake
+ for (int i = 0; i < (gap*2); i++, ++b) {
+ CPPUNIT_ASSERT_EQUAL(gap - i, a - b);
+ CPPUNIT_ASSERT_EQUAL(i - gap, b - a);
+ }
}
};
