Make UniqueNumberGenerator::AddKnownId() return a value
Make AddKnownId() return a value to indicate whether the ID was
known before, or has only been made known now.
This allows users of the class to RTC_DCHECK that no collisions
existed in their seed set, for instance.
This change is done for the following classes:
1. UniqueNumberGenerator
2. UniqueRandomIdGenerator
3. UniqueStringGenerator
Bug: None
Change-Id: I627d2821cb76aa333075e36575088d76dbeb3665
Reviewed-on: https://webrtc-review.googlesource.com/c/121780
Commit-Queue: Elad Alon <eladalon@webrtc.org>
Reviewed-by: Amit Hilbuch <amithi@webrtc.org>
Reviewed-by: Steve Anton <steveanton@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#26621}diff --git a/rtc_base/unique_id_generator.cc b/rtc_base/unique_id_generator.cc
index 62cd068..d41fa8d 100644
--- a/rtc_base/unique_id_generator.cc
+++ b/rtc_base/unique_id_generator.cc
@@ -26,8 +26,8 @@
UniqueRandomIdGenerator::~UniqueRandomIdGenerator() = default;
uint32_t UniqueRandomIdGenerator::GenerateId() {
+ RTC_CHECK_LT(known_ids_.size(), std::numeric_limits<uint32_t>::max() - 1);
while (true) {
- RTC_CHECK_LT(known_ids_.size(), std::numeric_limits<uint32_t>::max());
auto pair = known_ids_.insert(CreateRandomNonZeroId());
if (pair.second) {
return *pair.first;
@@ -35,8 +35,8 @@
}
}
-void UniqueRandomIdGenerator::AddKnownId(uint32_t value) {
- known_ids_.insert(value);
+bool UniqueRandomIdGenerator::AddKnownId(uint32_t value) {
+ return known_ids_.insert(value).second;
}
UniqueStringGenerator::UniqueStringGenerator() : unique_number_generator_() {}
@@ -52,13 +52,14 @@
return ToString(unique_number_generator_.GenerateNumber());
}
-void UniqueStringGenerator::AddKnownId(const std::string& value) {
+bool UniqueStringGenerator::AddKnownId(const std::string& value) {
absl::optional<uint32_t> int_value = StringToNumber<uint32_t>(value);
// The underlying generator works for uint32_t values, so if the provided
// value is not a uint32_t it will never be generated anyway.
if (int_value.has_value()) {
- unique_number_generator_.AddKnownId(int_value.value());
+ return unique_number_generator_.AddKnownId(int_value.value());
}
+ return false;
}
} // namespace rtc
diff --git a/rtc_base/unique_id_generator.h b/rtc_base/unique_id_generator.h
index 849daa97..836dc70 100644
--- a/rtc_base/unique_id_generator.h
+++ b/rtc_base/unique_id_generator.h
@@ -43,7 +43,8 @@
TIntegral operator()() { return GenerateNumber(); }
// Adds an id that this generator should no longer generate.
- void AddKnownId(TIntegral value);
+ // Return value indicates whether the ID was hitherto unknown.
+ bool AddKnownId(TIntegral value);
private:
static_assert(std::is_integral<TIntegral>::value, "Must be integral type.");
@@ -71,7 +72,8 @@
uint32_t operator()() { return GenerateId(); }
// Adds an id that this generator should no longer generate.
- void AddKnownId(uint32_t value);
+ // Return value indicates whether the ID was hitherto unknown.
+ bool AddKnownId(uint32_t value);
private:
std::set<uint32_t> known_ids_;
@@ -93,7 +95,8 @@
std::string operator()() { return GenerateString(); }
// Adds an id that this generator should no longer generate.
- void AddKnownId(const std::string& value);
+ // Return value indicates whether the ID was hitherto unknown.
+ bool AddKnownId(const std::string& value);
private:
// This implementation will be simple and will generate "0", "1", ...
@@ -123,8 +126,8 @@
}
template <typename TIntegral>
-void UniqueNumberGenerator<TIntegral>::AddKnownId(TIntegral value) {
- known_ids_.insert(value);
+bool UniqueNumberGenerator<TIntegral>::AddKnownId(TIntegral value) {
+ return known_ids_.insert(value).second;
}
} // namespace rtc
diff --git a/rtc_base/unique_id_generator_unittest.cc b/rtc_base/unique_id_generator_unittest.cc
index 1634d56..7ce192c 100644
--- a/rtc_base/unique_id_generator_unittest.cc
+++ b/rtc_base/unique_id_generator_unittest.cc
@@ -29,6 +29,7 @@
using test_types = ::testing::Types<UniqueNumberGenerator<uint8_t>,
UniqueNumberGenerator<uint16_t>,
UniqueNumberGenerator<uint32_t>,
+ UniqueNumberGenerator<int>,
UniqueRandomIdGenerator,
UniqueStringGenerator>;
@@ -107,4 +108,43 @@
EXPECT_THAT(intersection, IsEmpty());
}
+TYPED_TEST(UniqueIdGeneratorTest, AddKnownIdOnNewIdReturnsTrue) {
+ typedef TypeParam Generator;
+
+ rtc::InitRandom(0);
+ Generator generator1;
+ const typename Generator::value_type id = generator1();
+
+ rtc::InitRandom(0);
+ Generator generator2;
+ EXPECT_TRUE(generator2.AddKnownId(id));
+}
+
+TYPED_TEST(UniqueIdGeneratorTest, AddKnownIdCalledAgainForSameIdReturnsFalse) {
+ typedef TypeParam Generator;
+
+ rtc::InitRandom(0);
+ Generator generator1;
+ const typename Generator::value_type id = generator1();
+
+ rtc::InitRandom(0);
+ Generator generator2;
+ ASSERT_TRUE(generator2.AddKnownId(id));
+ EXPECT_FALSE(generator2.AddKnownId(id));
+}
+
+TYPED_TEST(UniqueIdGeneratorTest,
+ AddKnownIdOnIdProvidedAsKnownToCtorReturnsFalse) {
+ typedef TypeParam Generator;
+
+ rtc::InitRandom(0);
+ Generator generator1;
+ const typename Generator::value_type id = generator1();
+ std::vector<typename Generator::value_type> known_values = {id};
+
+ rtc::InitRandom(0);
+ Generator generator2(known_values);
+ EXPECT_FALSE(generator2.AddKnownId(id));
+}
+
} // namespace rtc
