blob: 23b551648d25ed016fcec55ec15f16e23bcc0475 [file] [log] [blame]
// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "spdy/core/hpack/hpack_header_table.h"
#include <algorithm>
#include <cstdint>
#include <set>
#include <string>
#include <vector>
#include "common/platform/api/quiche_test.h"
#include "spdy/core/hpack/hpack_constants.h"
#include "spdy/core/hpack/hpack_entry.h"
#include "spdy/core/hpack/hpack_static_table.h"
namespace spdy {
using std::distance;
namespace test {
class HpackHeaderTablePeer {
public:
explicit HpackHeaderTablePeer(HpackHeaderTable* table) : table_(table) {}
const HpackHeaderTable::DynamicEntryTable& dynamic_entries() {
return table_->dynamic_entries_;
}
const HpackHeaderTable::StaticEntryTable& static_entries() {
return table_->static_entries_;
}
const HpackEntry* GetFirstStaticEntry() {
return &table_->static_entries_.front();
}
const HpackEntry* GetLastStaticEntry() {
return &table_->static_entries_.back();
}
std::vector<HpackEntry*> EvictionSet(absl::string_view name,
absl::string_view value) {
HpackHeaderTable::DynamicEntryTable::iterator begin, end;
table_->EvictionSet(name, value, &begin, &end);
std::vector<HpackEntry*> result;
for (; begin != end; ++begin) {
result.push_back(&(*begin));
}
return result;
}
size_t dynamic_table_insertions() {
return table_->dynamic_table_insertions_;
}
size_t EvictionCountForEntry(absl::string_view name,
absl::string_view value) {
return table_->EvictionCountForEntry(name, value);
}
size_t EvictionCountToReclaim(size_t reclaim_size) {
return table_->EvictionCountToReclaim(reclaim_size);
}
void Evict(size_t count) { return table_->Evict(count); }
private:
HpackHeaderTable* table_;
};
} // namespace test
namespace {
class HpackHeaderTableTest : public QuicheTest {
protected:
typedef std::vector<HpackEntry> HpackEntryVector;
HpackHeaderTableTest() : table_(), peer_(&table_) {}
// Returns an entry whose Size() is equal to the given one.
static HpackEntry MakeEntryOfSize(uint32_t size) {
EXPECT_GE(size, kHpackEntrySizeOverhead);
std::string name((size - kHpackEntrySizeOverhead) / 2, 'n');
std::string value(size - kHpackEntrySizeOverhead - name.size(), 'v');
HpackEntry entry(name, value);
EXPECT_EQ(size, entry.Size());
return entry;
}
// Returns a vector of entries whose total size is equal to the given
// one.
static HpackEntryVector MakeEntriesOfTotalSize(uint32_t total_size) {
EXPECT_GE(total_size, kHpackEntrySizeOverhead);
uint32_t entry_size = kHpackEntrySizeOverhead;
uint32_t remaining_size = total_size;
HpackEntryVector entries;
while (remaining_size > 0) {
EXPECT_LE(entry_size, remaining_size);
entries.push_back(MakeEntryOfSize(entry_size));
remaining_size -= entry_size;
entry_size = std::min(remaining_size, entry_size + 32);
}
return entries;
}
// Adds the given vector of entries to the given header table,
// expecting no eviction to happen.
void AddEntriesExpectNoEviction(const HpackEntryVector& entries) {
for (auto it = entries.begin(); it != entries.end(); ++it) {
HpackHeaderTable::DynamicEntryTable::iterator begin, end;
table_.EvictionSet(it->name(), it->value(), &begin, &end);
EXPECT_EQ(0, distance(begin, end));
const HpackEntry* entry = table_.TryAddEntry(it->name(), it->value());
EXPECT_NE(entry, static_cast<HpackEntry*>(nullptr));
}
}
HpackHeaderTable table_;
test::HpackHeaderTablePeer peer_;
};
TEST_F(HpackHeaderTableTest, StaticTableInitialization) {
EXPECT_EQ(0u, table_.size());
EXPECT_EQ(kDefaultHeaderTableSizeSetting, table_.max_size());
EXPECT_EQ(kDefaultHeaderTableSizeSetting, table_.settings_size_bound());
EXPECT_EQ(0u, peer_.dynamic_entries().size());
EXPECT_EQ(0u, peer_.dynamic_table_insertions());
// Static entries have been populated and inserted into the table & index.
const HpackHeaderTable::StaticEntryTable& static_entries =
peer_.static_entries();
EXPECT_EQ(kStaticTableSize, static_entries.size());
// HPACK indexing scheme is 1-based.
size_t index = 1;
for (const HpackEntry& entry : static_entries) {
EXPECT_EQ(index, table_.GetByNameAndValue(entry.name(), entry.value()));
index++;
}
}
TEST_F(HpackHeaderTableTest, BasicDynamicEntryInsertionAndEviction) {
EXPECT_EQ(kStaticTableSize, peer_.static_entries().size());
const HpackEntry* first_static_entry = peer_.GetFirstStaticEntry();
const HpackEntry* last_static_entry = peer_.GetLastStaticEntry();
const HpackEntry* entry = table_.TryAddEntry("header-key", "Header Value");
EXPECT_EQ("header-key", entry->name());
EXPECT_EQ("Header Value", entry->value());
// Table counts were updated appropriately.
EXPECT_EQ(entry->Size(), table_.size());
EXPECT_EQ(1u, peer_.dynamic_entries().size());
EXPECT_EQ(kStaticTableSize, peer_.static_entries().size());
EXPECT_EQ(62u, table_.GetByNameAndValue("header-key", "Header Value"));
// Index of static entries does not change.
EXPECT_EQ(first_static_entry, peer_.GetFirstStaticEntry());
EXPECT_EQ(last_static_entry, peer_.GetLastStaticEntry());
// Evict |entry|. Table counts are again updated appropriately.
peer_.Evict(1);
EXPECT_EQ(0u, table_.size());
EXPECT_EQ(0u, peer_.dynamic_entries().size());
EXPECT_EQ(kStaticTableSize, peer_.static_entries().size());
// Index of static entries does not change.
EXPECT_EQ(first_static_entry, peer_.GetFirstStaticEntry());
EXPECT_EQ(last_static_entry, peer_.GetLastStaticEntry());
}
TEST_F(HpackHeaderTableTest, EntryIndexing) {
const HpackEntry* first_static_entry = peer_.GetFirstStaticEntry();
const HpackEntry* last_static_entry = peer_.GetLastStaticEntry();
// Static entries are queryable by name & value.
EXPECT_EQ(1u, table_.GetByName(first_static_entry->name()));
EXPECT_EQ(1u, table_.GetByNameAndValue(first_static_entry->name(),
first_static_entry->value()));
// Create a mix of entries which duplicate names, and names & values of both
// dynamic and static entries.
table_.TryAddEntry(first_static_entry->name(), first_static_entry->value());
table_.TryAddEntry(first_static_entry->name(), "Value Four");
table_.TryAddEntry("key-1", "Value One");
table_.TryAddEntry("key-2", "Value Three");
table_.TryAddEntry("key-1", "Value Two");
table_.TryAddEntry("key-2", "Value Three");
table_.TryAddEntry("key-2", "Value Four");
// The following entry is identical to the one at index 68. The smaller index
// is returned by GetByNameAndValue().
EXPECT_EQ(1u, table_.GetByNameAndValue(first_static_entry->name(),
first_static_entry->value()));
EXPECT_EQ(67u,
table_.GetByNameAndValue(first_static_entry->name(), "Value Four"));
EXPECT_EQ(66u, table_.GetByNameAndValue("key-1", "Value One"));
EXPECT_EQ(64u, table_.GetByNameAndValue("key-1", "Value Two"));
// The following entry is identical to the one at index 65. The smaller index
// is returned by GetByNameAndValue().
EXPECT_EQ(63u, table_.GetByNameAndValue("key-2", "Value Three"));
EXPECT_EQ(62u, table_.GetByNameAndValue("key-2", "Value Four"));
// Index of static entries does not change.
EXPECT_EQ(first_static_entry, peer_.GetFirstStaticEntry());
EXPECT_EQ(last_static_entry, peer_.GetLastStaticEntry());
// Querying by name returns the most recently added matching entry.
EXPECT_EQ(64u, table_.GetByName("key-1"));
EXPECT_EQ(62u, table_.GetByName("key-2"));
EXPECT_EQ(1u, table_.GetByName(first_static_entry->name()));
EXPECT_EQ(kHpackEntryNotFound, table_.GetByName("not-present"));
// Querying by name & value returns the lowest-index matching entry among
// static entries, and the highest-index one among dynamic entries.
EXPECT_EQ(66u, table_.GetByNameAndValue("key-1", "Value One"));
EXPECT_EQ(64u, table_.GetByNameAndValue("key-1", "Value Two"));
EXPECT_EQ(63u, table_.GetByNameAndValue("key-2", "Value Three"));
EXPECT_EQ(62u, table_.GetByNameAndValue("key-2", "Value Four"));
EXPECT_EQ(1u, table_.GetByNameAndValue(first_static_entry->name(),
first_static_entry->value()));
EXPECT_EQ(67u,
table_.GetByNameAndValue(first_static_entry->name(), "Value Four"));
EXPECT_EQ(kHpackEntryNotFound,
table_.GetByNameAndValue("key-1", "Not Present"));
EXPECT_EQ(kHpackEntryNotFound,
table_.GetByNameAndValue("not-present", "Value One"));
// Evict |entry1|. Queries for its name & value now return the static entry.
// |entry2| remains queryable.
peer_.Evict(1);
EXPECT_EQ(1u, table_.GetByNameAndValue(first_static_entry->name(),
first_static_entry->value()));
EXPECT_EQ(67u,
table_.GetByNameAndValue(first_static_entry->name(), "Value Four"));
// Evict |entry2|. Queries by its name & value are not found.
peer_.Evict(1);
EXPECT_EQ(kHpackEntryNotFound,
table_.GetByNameAndValue(first_static_entry->name(), "Value Four"));
// Index of static entries does not change.
EXPECT_EQ(first_static_entry, peer_.GetFirstStaticEntry());
EXPECT_EQ(last_static_entry, peer_.GetLastStaticEntry());
}
TEST_F(HpackHeaderTableTest, SetSizes) {
std::string key = "key", value = "value";
const HpackEntry* entry1 = table_.TryAddEntry(key, value);
const HpackEntry* entry2 = table_.TryAddEntry(key, value);
const HpackEntry* entry3 = table_.TryAddEntry(key, value);
// Set exactly large enough. No Evictions.
size_t max_size = entry1->Size() + entry2->Size() + entry3->Size();
table_.SetMaxSize(max_size);
EXPECT_EQ(3u, peer_.dynamic_entries().size());
// Set just too small. One eviction.
max_size = entry1->Size() + entry2->Size() + entry3->Size() - 1;
table_.SetMaxSize(max_size);
EXPECT_EQ(2u, peer_.dynamic_entries().size());
// Changing SETTINGS_HEADER_TABLE_SIZE.
EXPECT_EQ(kDefaultHeaderTableSizeSetting, table_.settings_size_bound());
// In production, the size passed to SetSettingsHeaderTableSize is never
// larger than table_.settings_size_bound().
table_.SetSettingsHeaderTableSize(kDefaultHeaderTableSizeSetting * 3 + 1);
EXPECT_EQ(kDefaultHeaderTableSizeSetting * 3 + 1, table_.max_size());
// SETTINGS_HEADER_TABLE_SIZE upper-bounds |table_.max_size()|,
// and will force evictions.
max_size = entry3->Size() - 1;
table_.SetSettingsHeaderTableSize(max_size);
EXPECT_EQ(max_size, table_.max_size());
EXPECT_EQ(max_size, table_.settings_size_bound());
EXPECT_EQ(0u, peer_.dynamic_entries().size());
}
TEST_F(HpackHeaderTableTest, EvictionCountForEntry) {
std::string key = "key", value = "value";
const HpackEntry* entry1 = table_.TryAddEntry(key, value);
const HpackEntry* entry2 = table_.TryAddEntry(key, value);
size_t entry3_size = HpackEntry::Size(key, value);
// Just enough capacity for third entry.
table_.SetMaxSize(entry1->Size() + entry2->Size() + entry3_size);
EXPECT_EQ(0u, peer_.EvictionCountForEntry(key, value));
EXPECT_EQ(1u, peer_.EvictionCountForEntry(key, value + "x"));
// No extra capacity. Third entry would force evictions.
table_.SetMaxSize(entry1->Size() + entry2->Size());
EXPECT_EQ(1u, peer_.EvictionCountForEntry(key, value));
EXPECT_EQ(2u, peer_.EvictionCountForEntry(key, value + "x"));
}
TEST_F(HpackHeaderTableTest, EvictionCountToReclaim) {
std::string key = "key", value = "value";
const HpackEntry* entry1 = table_.TryAddEntry(key, value);
const HpackEntry* entry2 = table_.TryAddEntry(key, value);
EXPECT_EQ(1u, peer_.EvictionCountToReclaim(1));
EXPECT_EQ(1u, peer_.EvictionCountToReclaim(entry1->Size()));
EXPECT_EQ(2u, peer_.EvictionCountToReclaim(entry1->Size() + 1));
EXPECT_EQ(2u, peer_.EvictionCountToReclaim(entry1->Size() + entry2->Size()));
}
// Fill a header table with entries. Make sure the entries are in
// reverse order in the header table.
TEST_F(HpackHeaderTableTest, TryAddEntryBasic) {
EXPECT_EQ(0u, table_.size());
EXPECT_EQ(table_.settings_size_bound(), table_.max_size());
HpackEntryVector entries = MakeEntriesOfTotalSize(table_.max_size());
// Most of the checks are in AddEntriesExpectNoEviction().
AddEntriesExpectNoEviction(entries);
EXPECT_EQ(table_.max_size(), table_.size());
EXPECT_EQ(table_.settings_size_bound(), table_.size());
}
// Fill a header table with entries, and then ramp the table's max
// size down to evict an entry one at a time. Make sure the eviction
// happens as expected.
TEST_F(HpackHeaderTableTest, SetMaxSize) {
HpackEntryVector entries =
MakeEntriesOfTotalSize(kDefaultHeaderTableSizeSetting / 2);
AddEntriesExpectNoEviction(entries);
for (auto it = entries.begin(); it != entries.end(); ++it) {
size_t expected_count = distance(it, entries.end());
EXPECT_EQ(expected_count, peer_.dynamic_entries().size());
table_.SetMaxSize(table_.size() + 1);
EXPECT_EQ(expected_count, peer_.dynamic_entries().size());
table_.SetMaxSize(table_.size());
EXPECT_EQ(expected_count, peer_.dynamic_entries().size());
--expected_count;
table_.SetMaxSize(table_.size() - 1);
EXPECT_EQ(expected_count, peer_.dynamic_entries().size());
}
EXPECT_EQ(0u, table_.size());
}
// Fill a header table with entries, and then add an entry just big
// enough to cause eviction of all but one entry. Make sure the
// eviction happens as expected and the long entry is inserted into
// the table.
TEST_F(HpackHeaderTableTest, TryAddEntryEviction) {
HpackEntryVector entries = MakeEntriesOfTotalSize(table_.max_size());
AddEntriesExpectNoEviction(entries);
// The first entry in the dynamic table.
const HpackEntry* survivor_entry = &peer_.dynamic_entries().front();
HpackEntry long_entry =
MakeEntryOfSize(table_.max_size() - survivor_entry->Size());
// All dynamic entries but the first are to be evicted.
EXPECT_EQ(peer_.dynamic_entries().size() - 1,
peer_.EvictionSet(long_entry.name(), long_entry.value()).size());
table_.TryAddEntry(long_entry.name(), long_entry.value());
EXPECT_EQ(2u, peer_.dynamic_entries().size());
EXPECT_EQ(63u, table_.GetByNameAndValue(survivor_entry->name(),
survivor_entry->value()));
EXPECT_EQ(62u,
table_.GetByNameAndValue(long_entry.name(), long_entry.value()));
}
// Fill a header table with entries, and then add an entry bigger than
// the entire table. Make sure no entry remains in the table.
TEST_F(HpackHeaderTableTest, TryAddTooLargeEntry) {
HpackEntryVector entries = MakeEntriesOfTotalSize(table_.max_size());
AddEntriesExpectNoEviction(entries);
const HpackEntry long_entry = MakeEntryOfSize(table_.max_size() + 1);
// All entries are to be evicted.
EXPECT_EQ(peer_.dynamic_entries().size(),
peer_.EvictionSet(long_entry.name(), long_entry.value()).size());
const HpackEntry* new_entry =
table_.TryAddEntry(long_entry.name(), long_entry.value());
EXPECT_EQ(new_entry, static_cast<HpackEntry*>(nullptr));
EXPECT_EQ(0u, peer_.dynamic_entries().size());
}
} // namespace
} // namespace spdy