Initial checkin.
git-svn-id: http://leveldb.googlecode.com/svn/trunk@2 62dab493-f737-651d-591e-8d6aee1b9529
diff --git a/util/arena.cc b/util/arena.cc
new file mode 100644
index 0000000..4bf6e36
--- /dev/null
+++ b/util/arena.cc
@@ -0,0 +1,68 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "util/arena.h"
+#include <assert.h>
+
+namespace leveldb {
+
+static const int kBlockSize = 4096;
+
+Arena::Arena() {
+ blocks_memory_ = 0;
+ alloc_ptr_ = NULL; // First allocation will allocate a block
+ alloc_bytes_remaining_ = 0;
+}
+
+Arena::~Arena() {
+ for (int i = 0; i < blocks_.size(); i++) {
+ delete[] blocks_[i];
+ }
+}
+
+char* Arena::AllocateFallback(size_t bytes) {
+ if (bytes > kBlockSize / 4) {
+ // Object is more than a quarter of our block size. Allocate it separately
+ // to avoid wasting too much space in leftover bytes.
+ char* result = AllocateNewBlock(bytes);
+ return result;
+ }
+
+ // We waste the remaining space in the current block.
+ alloc_ptr_ = AllocateNewBlock(kBlockSize);
+ alloc_bytes_remaining_ = kBlockSize;
+
+ char* result = alloc_ptr_;
+ alloc_ptr_ += bytes;
+ alloc_bytes_remaining_ -= bytes;
+ return result;
+}
+
+char* Arena::AllocateAligned(size_t bytes) {
+ const int align = sizeof(void*); // We'll align to pointer size
+ assert((align & (align-1)) == 0); // Pointer size should be a power of 2
+ size_t current_mod = reinterpret_cast<uintptr_t>(alloc_ptr_) & (align-1);
+ size_t slop = (current_mod == 0 ? 0 : align - current_mod);
+ size_t needed = bytes + slop;
+ char* result;
+ if (needed <= alloc_bytes_remaining_) {
+ result = alloc_ptr_ + slop;
+ alloc_ptr_ += needed;
+ alloc_bytes_remaining_ -= needed;
+ } else {
+ // AllocateFallback always returned aligned memory
+ result = AllocateFallback(bytes);
+ }
+ assert((reinterpret_cast<uintptr_t>(result) & (align-1)) == 0);
+ return result;
+}
+
+char* Arena::AllocateNewBlock(size_t block_bytes) {
+ char* result = new char[block_bytes];
+ blocks_memory_ += block_bytes;
+ blocks_.push_back(result);
+ return result;
+}
+
+}
diff --git a/util/arena.h b/util/arena.h
new file mode 100644
index 0000000..fcb5d5b
--- /dev/null
+++ b/util/arena.h
@@ -0,0 +1,68 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#ifndef STORAGE_LEVELDB_UTIL_ARENA_H_
+#define STORAGE_LEVELDB_UTIL_ARENA_H_
+
+#include <cstddef>
+#include <vector>
+#include <assert.h>
+#include <stdint.h>
+
+namespace leveldb {
+
+class Arena {
+ public:
+ Arena();
+ ~Arena();
+
+ // Return a pointer to a newly allocated memory block of "bytes" bytes.
+ char* Allocate(size_t bytes);
+
+ // Allocate memory with the normal alignment guarantees provided by malloc
+ char* AllocateAligned(size_t bytes);
+
+ // Returns an estimate of the total memory usage of data allocated
+ // by the arena (including space allocated but not yet used for user
+ // allocations).
+ size_t MemoryUsage() const {
+ return blocks_memory_ + blocks_.capacity() * sizeof(char*);
+ }
+
+ private:
+ char* AllocateFallback(size_t bytes);
+ char* AllocateNewBlock(size_t block_bytes);
+
+ // Allocation state
+ char* alloc_ptr_;
+ size_t alloc_bytes_remaining_;
+
+ // Array of new[] allocated memory blocks
+ std::vector<char*> blocks_;
+
+ // Bytes of memory in blocks allocated so far
+ size_t blocks_memory_;
+
+ // No copying allowed
+ Arena(const Arena&);
+ void operator=(const Arena&);
+};
+
+inline char* Arena::Allocate(size_t bytes) {
+ // The semantics of what to return are a bit messy if we allow
+ // 0-byte allocations, so we disallow them here (we don't need
+ // them for our internal use).
+ assert(bytes > 0);
+ if (bytes <= alloc_bytes_remaining_) {
+ char* result = alloc_ptr_;
+ alloc_ptr_ += bytes;
+ alloc_bytes_remaining_ -= bytes;
+ return result;
+ }
+ return AllocateFallback(bytes);
+}
+
+}
+
+#endif // STORAGE_LEVELDB_UTIL_ARENA_H_
diff --git a/util/arena_test.cc b/util/arena_test.cc
new file mode 100644
index 0000000..c33b552
--- /dev/null
+++ b/util/arena_test.cc
@@ -0,0 +1,68 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "util/arena.h"
+
+#include "util/random.h"
+#include "util/testharness.h"
+
+namespace leveldb {
+
+class ArenaTest { };
+
+TEST(ArenaTest, Empty) {
+ Arena arena;
+}
+
+TEST(ArenaTest, Simple) {
+ std::vector<std::pair<size_t, char*> > allocated;
+ Arena arena;
+ const int N = 100000;
+ size_t bytes = 0;
+ Random rnd(301);
+ for (int i = 0; i < N; i++) {
+ size_t s;
+ if (i % (N / 10) == 0) {
+ s = i;
+ } else {
+ s = rnd.OneIn(4000) ? rnd.Uniform(6000) :
+ (rnd.OneIn(10) ? rnd.Uniform(100) : rnd.Uniform(20));
+ }
+ if (s == 0) {
+ // Our arena disallows size 0 allocations.
+ s = 1;
+ }
+ char* r;
+ if (rnd.OneIn(10)) {
+ r = arena.AllocateAligned(s);
+ } else {
+ r = arena.Allocate(s);
+ }
+
+ for (int b = 0; b < s; b++) {
+ // Fill the "i"th allocation with a known bit pattern
+ r[b] = i % 256;
+ }
+ bytes += s;
+ allocated.push_back(std::make_pair(s, r));
+ ASSERT_GE(arena.MemoryUsage(), bytes);
+ if (i > N/10) {
+ ASSERT_LE(arena.MemoryUsage(), bytes * 1.10);
+ }
+ }
+ for (int i = 0; i < allocated.size(); i++) {
+ size_t num_bytes = allocated[i].first;
+ const char* p = allocated[i].second;
+ for (int b = 0; b < num_bytes; b++) {
+ // Check the "i"th allocation for the known bit pattern
+ ASSERT_EQ(int(p[b]) & 0xff, i % 256);
+ }
+ }
+}
+
+}
+
+int main(int argc, char** argv) {
+ return leveldb::test::RunAllTests();
+}
diff --git a/util/cache.cc b/util/cache.cc
new file mode 100644
index 0000000..958de66
--- /dev/null
+++ b/util/cache.cc
@@ -0,0 +1,253 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#if defined(LEVELDB_PLATFORM_POSIX) || defined(LEVELDB_PLATFORM_ANDROID)
+#include <unordered_set>
+#elif defined(LEVELDB_PLATFORM_CHROMIUM)
+#include "base/hash_tables.h"
+#else
+#include <hash_set> // TODO(sanjay): Switch to unordered_set when possible.
+#endif
+
+#include <assert.h>
+
+#include "include/cache.h"
+#include "port/port.h"
+#include "util/hash.h"
+#include "util/mutexlock.h"
+
+namespace leveldb {
+
+Cache::~Cache() {
+}
+
+namespace {
+
+// LRU cache implementation
+
+// An entry is a variable length heap-allocated structure. Entries
+// are kept in a circular doubly linked list ordered by access time.
+struct LRUHandle {
+ void* value;
+ void (*deleter)(const Slice&, void* value);
+ LRUHandle* next;
+ LRUHandle* prev;
+ size_t charge; // TODO(opt): Only allow uint32_t?
+ size_t key_length;
+ size_t refs; // TODO(opt): Pack with "key_length"?
+ char key_data[1]; // Beginning of key
+
+ Slice key() const {
+ // For cheaper lookups, we allow a temporary Handle object
+ // to store a pointer to a key in "value".
+ if (next == this) {
+ return *(reinterpret_cast<Slice*>(value));
+ } else {
+ return Slice(key_data, key_length);
+ }
+ }
+};
+
+// Pick a platform specific hash_set instantiation
+#if defined(LEVELDB_PLATFORM_CHROMIUM) && defined(OS_WIN)
+ // Microsoft's hash_set deviates from the standard. See
+ // http://msdn.microsoft.com/en-us/library/1t4xas78(v=vs.80).aspx
+ // for details. Basically the 2 param () operator is a less than and
+ // the 1 param () operator is a hash function.
+ struct HandleHashCompare : public stdext::hash_compare<LRUHandle*> {
+ size_t operator() (LRUHandle* h) const {
+ Slice k = h->key();
+ return Hash(k.data(), k.size(), 0);
+ }
+ bool operator() (LRUHandle* a, LRUHandle* b) const {
+ return a->key().compare(b->key()) < 0;
+ }
+ };
+ typedef base::hash_set<LRUHandle*, HandleHashCompare> HandleTable;
+#else
+ struct HandleHash {
+ inline size_t operator()(LRUHandle* h) const {
+ Slice k = h->key();
+ return Hash(k.data(), k.size(), 0);
+ }
+ };
+
+ struct HandleEq {
+ inline bool operator()(LRUHandle* a, LRUHandle* b) const {
+ return a->key() == b->key();
+ }
+ };
+# if defined(LEVELDB_PLATFORM_CHROMIUM)
+ typedef base::hash_set<LRUHandle*, HandleHash, HandleEq> HandleTable;
+# elif defined(LEVELDB_PLATFORM_POSIX) || defined(LEVELDB_PLATFORM_ANDROID)
+ typedef std::unordered_set<LRUHandle*, HandleHash, HandleEq> HandleTable;
+# else
+ typedef __gnu_cxx::hash_set<LRUHandle*, HandleHash, HandleEq> HandleTable;
+# endif
+#endif
+
+class LRUCache : public Cache {
+ public:
+ explicit LRUCache(size_t capacity);
+ virtual ~LRUCache();
+
+ virtual Handle* Insert(const Slice& key, void* value, size_t charge,
+ void (*deleter)(const Slice& key, void* value));
+ virtual Handle* Lookup(const Slice& key);
+ virtual void Release(Handle* handle);
+ virtual void* Value(Handle* handle);
+ virtual void Erase(const Slice& key);
+ virtual uint64_t NewId();
+
+ private:
+ void LRU_Remove(LRUHandle* e);
+ void LRU_Append(LRUHandle* e);
+ void Unref(LRUHandle* e);
+
+ // Constructor parameters
+ const size_t capacity_;
+
+ // mutex_ protects the following state.
+ port::Mutex mutex_;
+ size_t usage_;
+ uint64_t last_id_;
+
+ // Dummy head of LRU list.
+ // lru.prev is newest entry, lru.next is oldest entry.
+ LRUHandle lru_;
+
+ HandleTable table_;
+};
+
+LRUCache::LRUCache(size_t capacity)
+ : capacity_(capacity),
+ usage_(0),
+ last_id_(0) {
+ // Make empty circular linked list
+ lru_.next = &lru_;
+ lru_.prev = &lru_;
+}
+
+LRUCache::~LRUCache() {
+ table_.clear();
+ for (LRUHandle* e = lru_.next; e != &lru_; ) {
+ LRUHandle* next = e->next;
+ assert(e->refs == 1); // Error if caller has an unreleased handle
+ Unref(e);
+ e = next;
+ }
+}
+
+void LRUCache::Unref(LRUHandle* e) {
+ assert(e->refs > 0);
+ e->refs--;
+ if (e->refs <= 0) {
+ usage_ -= e->charge;
+ (*e->deleter)(e->key(), e->value);
+ free(e);
+ }
+}
+
+void LRUCache::LRU_Remove(LRUHandle* e) {
+ e->next->prev = e->prev;
+ e->prev->next = e->next;
+}
+
+void LRUCache::LRU_Append(LRUHandle* e) {
+ // Make "e" newest entry by inserting just before lru_
+ e->next = &lru_;
+ e->prev = lru_.prev;
+ e->prev->next = e;
+ e->next->prev = e;
+}
+
+Cache::Handle* LRUCache::Lookup(const Slice& key) {
+ MutexLock l(&mutex_);
+
+ LRUHandle dummy;
+ dummy.next = &dummy;
+ dummy.value = const_cast<Slice*>(&key);
+ HandleTable::iterator iter = table_.find(&dummy);
+ if (iter == table_.end()) {
+ return NULL;
+ } else {
+ LRUHandle* e = const_cast<LRUHandle*>(*iter);
+ e->refs++;
+ LRU_Remove(e);
+ LRU_Append(e);
+ return reinterpret_cast<Handle*>(e);
+ }
+}
+
+void* LRUCache::Value(Handle* handle) {
+ return reinterpret_cast<LRUHandle*>(handle)->value;
+}
+
+void LRUCache::Release(Handle* handle) {
+ MutexLock l(&mutex_);
+ Unref(reinterpret_cast<LRUHandle*>(handle));
+}
+
+Cache::Handle* LRUCache::Insert(const Slice& key, void* value, size_t charge,
+ void (*deleter)(const Slice& key, void* value)) {
+ MutexLock l(&mutex_);
+
+ LRUHandle* e = reinterpret_cast<LRUHandle*>(
+ malloc(sizeof(LRUHandle)-1 + key.size()));
+ e->value = value;
+ e->deleter = deleter;
+ e->charge = charge;
+ e->key_length = key.size();
+ e->refs = 2; // One from LRUCache, one for the returned handle
+ memcpy(e->key_data, key.data(), key.size());
+ LRU_Append(e);
+ usage_ += charge;
+
+ std::pair<HandleTable::iterator,bool> p = table_.insert(e);
+ if (!p.second) {
+ // Kill existing entry
+ LRUHandle* old = const_cast<LRUHandle*>(*(p.first));
+ LRU_Remove(old);
+ table_.erase(p.first);
+ table_.insert(e);
+ Unref(old);
+ }
+
+ while (usage_ > capacity_ && lru_.next != &lru_) {
+ LRUHandle* old = lru_.next;
+ LRU_Remove(old);
+ table_.erase(old);
+ Unref(old);
+ }
+
+ return reinterpret_cast<Handle*>(e);
+}
+
+void LRUCache::Erase(const Slice& key) {
+ MutexLock l(&mutex_);
+
+ LRUHandle dummy;
+ dummy.next = &dummy;
+ dummy.value = const_cast<Slice*>(&key);
+ HandleTable::iterator iter = table_.find(&dummy);
+ if (iter != table_.end()) {
+ LRUHandle* e = const_cast<LRUHandle*>(*iter);
+ LRU_Remove(e);
+ table_.erase(iter);
+ Unref(e);
+ }
+}
+
+uint64_t LRUCache::NewId() {
+ MutexLock l(&mutex_);
+ return ++(last_id_);
+}
+
+} // end anonymous namespace
+
+Cache* NewLRUCache(size_t capacity) {
+ return new LRUCache(capacity);
+}
+
+}
diff --git a/util/cache_test.cc b/util/cache_test.cc
new file mode 100644
index 0000000..05de5d9
--- /dev/null
+++ b/util/cache_test.cc
@@ -0,0 +1,169 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "include/cache.h"
+
+#include <vector>
+#include "util/coding.h"
+#include "util/testharness.h"
+
+namespace leveldb {
+
+// Conversions between numeric keys/values and the types expected by Cache.
+static std::string EncodeKey(int k) {
+ std::string result;
+ PutFixed32(&result, k);
+ return result;
+}
+static int DecodeKey(const Slice& k) {
+ assert(k.size() == 4);
+ return DecodeFixed32(k.data());
+}
+static void* EncodeValue(uintptr_t v) { return reinterpret_cast<void*>(v); }
+static int DecodeValue(void* v) { return reinterpret_cast<uintptr_t>(v); }
+
+class CacheTest {
+ public:
+ static CacheTest* current_;
+
+ static void Deleter(const Slice& key, void* v) {
+ current_->deleted_keys_.push_back(DecodeKey(key));
+ current_->deleted_values_.push_back(DecodeValue(v));
+ }
+
+ static const int kCacheSize = 100;
+ std::vector<int> deleted_keys_;
+ std::vector<int> deleted_values_;
+ Cache* cache_;
+
+ CacheTest() : cache_(NewLRUCache(kCacheSize)) {
+ current_ = this;
+ }
+
+ ~CacheTest() {
+ delete cache_;
+ }
+
+ int Lookup(int key) {
+ Cache::Handle* handle = cache_->Lookup(EncodeKey(key));
+ const int r = (handle == NULL) ? -1 : DecodeValue(cache_->Value(handle));
+ if (handle != NULL) {
+ cache_->Release(handle);
+ }
+ return r;
+ }
+
+ void Insert(int key, int value, int charge = 1) {
+ cache_->Release(cache_->Insert(EncodeKey(key), EncodeValue(value), charge,
+ &CacheTest::Deleter));
+ }
+
+ void Erase(int key) {
+ cache_->Erase(EncodeKey(key));
+ }
+};
+CacheTest* CacheTest::current_;
+
+TEST(CacheTest, HitAndMiss) {
+ ASSERT_EQ(-1, Lookup(100));
+
+ Insert(100, 101);
+ ASSERT_EQ(101, Lookup(100));
+ ASSERT_EQ(-1, Lookup(200));
+ ASSERT_EQ(-1, Lookup(300));
+
+ Insert(200, 201);
+ ASSERT_EQ(101, Lookup(100));
+ ASSERT_EQ(201, Lookup(200));
+ ASSERT_EQ(-1, Lookup(300));
+
+ Insert(100, 102);
+ ASSERT_EQ(102, Lookup(100));
+ ASSERT_EQ(201, Lookup(200));
+ ASSERT_EQ(-1, Lookup(300));
+
+ ASSERT_EQ(1, deleted_keys_.size());
+ ASSERT_EQ(100, deleted_keys_[0]);
+ ASSERT_EQ(101, deleted_values_[0]);
+}
+
+TEST(CacheTest, Erase) {
+ Erase(200);
+ ASSERT_EQ(0, deleted_keys_.size());
+
+ Insert(100, 101);
+ Insert(200, 201);
+ Erase(100);
+ ASSERT_EQ(-1, Lookup(100));
+ ASSERT_EQ(201, Lookup(200));
+ ASSERT_EQ(1, deleted_keys_.size());
+ ASSERT_EQ(100, deleted_keys_[0]);
+ ASSERT_EQ(101, deleted_values_[0]);
+
+ Erase(100);
+ ASSERT_EQ(-1, Lookup(100));
+ ASSERT_EQ(201, Lookup(200));
+ ASSERT_EQ(1, deleted_keys_.size());
+}
+
+TEST(CacheTest, EntriesArePinned) {
+ Insert(100, 101);
+ Cache::Handle* h1 = cache_->Lookup(EncodeKey(100));
+ ASSERT_EQ(101, DecodeValue(cache_->Value(h1)));
+
+ Insert(100, 102);
+ Cache::Handle* h2 = cache_->Lookup(EncodeKey(100));
+ ASSERT_EQ(102, DecodeValue(cache_->Value(h2)));
+ ASSERT_EQ(0, deleted_keys_.size());
+
+ cache_->Release(h1);
+ ASSERT_EQ(1, deleted_keys_.size());
+ ASSERT_EQ(100, deleted_keys_[0]);
+ ASSERT_EQ(101, deleted_values_[0]);
+
+ Erase(100);
+ ASSERT_EQ(-1, Lookup(100));
+ ASSERT_EQ(1, deleted_keys_.size());
+
+ cache_->Release(h2);
+ ASSERT_EQ(2, deleted_keys_.size());
+ ASSERT_EQ(100, deleted_keys_[1]);
+ ASSERT_EQ(102, deleted_values_[1]);
+}
+
+TEST(CacheTest, EvictionPolicy) {
+ Insert(100, 101);
+ Insert(200, 201);
+
+ // Frequently used entry must be kept around
+ for (int i = 0; i < kCacheSize; i++) {
+ Insert(1000+i, 2000+i);
+ ASSERT_EQ(2000+i, Lookup(1000+i));
+ ASSERT_EQ(101, Lookup(100));
+ }
+ ASSERT_EQ(101, Lookup(100));
+ ASSERT_EQ(2, deleted_keys_.size());
+ ASSERT_EQ(200, deleted_keys_[0]);
+ ASSERT_EQ(201, deleted_values_[0]);
+}
+
+TEST(CacheTest, HeavyEntry) {
+ Insert(100, 101);
+ Insert(200, 201, kCacheSize);
+ ASSERT_EQ(1, deleted_keys_.size());
+ ASSERT_EQ(100, deleted_keys_[0]);
+ ASSERT_EQ(101, deleted_values_[0]);
+}
+
+TEST(CacheTest, NewId) {
+ uint64_t a = cache_->NewId();
+ uint64_t b = cache_->NewId();
+ ASSERT_NE(a, b);
+}
+
+}
+
+int main(int argc, char** argv) {
+ return leveldb::test::RunAllTests();
+}
diff --git a/util/coding.cc b/util/coding.cc
new file mode 100644
index 0000000..680e2ad
--- /dev/null
+++ b/util/coding.cc
@@ -0,0 +1,194 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "util/coding.h"
+
+namespace leveldb {
+
+void EncodeFixed32(char* buf, uint32_t value) {
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+ memcpy(buf, &value, sizeof(value));
+#else
+ buf[0] = value & 0xff;
+ buf[1] = (value >> 8) & 0xff;
+ buf[2] = (value >> 16) & 0xff;
+ buf[3] = (value >> 24) & 0xff;
+#endif
+}
+
+void EncodeFixed64(char* buf, uint64_t value) {
+#if __BYTE_ORDER == __LITTLE_ENDIAN
+ memcpy(buf, &value, sizeof(value));
+#else
+ buf[0] = value & 0xff;
+ buf[1] = (value >> 8) & 0xff;
+ buf[2] = (value >> 16) & 0xff;
+ buf[3] = (value >> 24) & 0xff;
+ buf[4] = (value >> 32) & 0xff;
+ buf[5] = (value >> 40) & 0xff;
+ buf[6] = (value >> 48) & 0xff;
+ buf[7] = (value >> 56) & 0xff;
+#endif
+}
+
+void PutFixed32(std::string* dst, uint32_t value) {
+ char buf[sizeof(value)];
+ EncodeFixed32(buf, value);
+ dst->append(buf, sizeof(buf));
+}
+
+void PutFixed64(std::string* dst, uint64_t value) {
+ char buf[sizeof(value)];
+ EncodeFixed64(buf, value);
+ dst->append(buf, sizeof(buf));
+}
+
+char* EncodeVarint32(char* dst, uint32_t v) {
+ // Operate on characters as unsigneds
+ unsigned char* ptr = reinterpret_cast<unsigned char*>(dst);
+ static const int B = 128;
+ if (v < (1<<7)) {
+ *(ptr++) = v;
+ } else if (v < (1<<14)) {
+ *(ptr++) = v | B;
+ *(ptr++) = v>>7;
+ } else if (v < (1<<21)) {
+ *(ptr++) = v | B;
+ *(ptr++) = (v>>7) | B;
+ *(ptr++) = v>>14;
+ } else if (v < (1<<28)) {
+ *(ptr++) = v | B;
+ *(ptr++) = (v>>7) | B;
+ *(ptr++) = (v>>14) | B;
+ *(ptr++) = v>>21;
+ } else {
+ *(ptr++) = v | B;
+ *(ptr++) = (v>>7) | B;
+ *(ptr++) = (v>>14) | B;
+ *(ptr++) = (v>>21) | B;
+ *(ptr++) = v>>28;
+ }
+ return reinterpret_cast<char*>(ptr);
+}
+
+void PutVarint32(std::string* dst, uint32_t v) {
+ char buf[5];
+ char* ptr = EncodeVarint32(buf, v);
+ dst->append(buf, ptr - buf);
+}
+
+char* EncodeVarint64(char* dst, uint64_t v) {
+ static const int B = 128;
+ unsigned char* ptr = reinterpret_cast<unsigned char*>(dst);
+ while (v >= B) {
+ *(ptr++) = (v & (B-1)) | B;
+ v >>= 7;
+ }
+ *(ptr++) = v;
+ return reinterpret_cast<char*>(ptr);
+}
+
+void PutVarint64(std::string* dst, uint64_t v) {
+ char buf[10];
+ char* ptr = EncodeVarint64(buf, v);
+ dst->append(buf, ptr - buf);
+}
+
+void PutLengthPrefixedSlice(std::string* dst, const Slice& value) {
+ PutVarint32(dst, value.size());
+ dst->append(value.data(), value.size());
+}
+
+int VarintLength(uint64_t v) {
+ int len = 1;
+ while (v >= 128) {
+ v >>= 7;
+ len++;
+ }
+ return len;
+}
+
+const char* GetVarint32PtrFallback(const char* p,
+ const char* limit,
+ uint32_t* value) {
+ uint32_t result = 0;
+ for (uint32_t shift = 0; shift <= 28 && p < limit; shift += 7) {
+ uint32_t byte = *(reinterpret_cast<const unsigned char*>(p));
+ p++;
+ if (byte & 128) {
+ // More bytes are present
+ result |= ((byte & 127) << shift);
+ } else {
+ result |= (byte << shift);
+ *value = result;
+ return reinterpret_cast<const char*>(p);
+ }
+ }
+ return NULL;
+}
+
+bool GetVarint32(Slice* input, uint32_t* value) {
+ const char* p = input->data();
+ const char* limit = p + input->size();
+ const char* q = GetVarint32Ptr(p, limit, value);
+ if (q == NULL) {
+ return false;
+ } else {
+ *input = Slice(q, limit - q);
+ return true;
+ }
+}
+
+const char* GetVarint64Ptr(const char* p, const char* limit, uint64_t* value) {
+ uint64_t result = 0;
+ for (uint32_t shift = 0; shift <= 63 && p < limit; shift += 7) {
+ uint64_t byte = *(reinterpret_cast<const unsigned char*>(p));
+ p++;
+ if (byte & 128) {
+ // More bytes are present
+ result |= ((byte & 127) << shift);
+ } else {
+ result |= (byte << shift);
+ *value = result;
+ return reinterpret_cast<const char*>(p);
+ }
+ }
+ return NULL;
+}
+
+bool GetVarint64(Slice* input, uint64_t* value) {
+ const char* p = input->data();
+ const char* limit = p + input->size();
+ const char* q = GetVarint64Ptr(p, limit, value);
+ if (q == NULL) {
+ return false;
+ } else {
+ *input = Slice(q, limit - q);
+ return true;
+ }
+}
+
+const char* GetLengthPrefixedSlice(const char* p, const char* limit,
+ Slice* result) {
+ uint32_t len;
+ p = GetVarint32Ptr(p, limit, &len);
+ if (p == NULL) return NULL;
+ if (p + len > limit) return NULL;
+ *result = Slice(p, len);
+ return p + len;
+}
+
+bool GetLengthPrefixedSlice(Slice* input, Slice* result) {
+ uint32_t len;
+ if (GetVarint32(input, &len) &&
+ input->size() >= len) {
+ *result = Slice(input->data(), len);
+ input->remove_prefix(len);
+ return true;
+ } else {
+ return false;
+ }
+}
+
+}
diff --git a/util/coding.h b/util/coding.h
new file mode 100644
index 0000000..a42e714
--- /dev/null
+++ b/util/coding.h
@@ -0,0 +1,104 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+//
+// Endian-neutral encoding:
+// * Fixed-length numbers are encoded with least-significant byte first
+// * In addition we support variable length "varint" encoding
+// * Strings are encoded prefixed by their length in varint format
+
+#ifndef STORAGE_LEVELDB_UTIL_CODING_H_
+#define STORAGE_LEVELDB_UTIL_CODING_H_
+
+#include <stdint.h>
+#include <string.h>
+#include <string>
+#include "include/slice.h"
+#include "port/port.h"
+
+namespace leveldb {
+
+// Standard Put... routines append to a string
+extern void PutFixed32(std::string* dst, uint32_t value);
+extern void PutFixed64(std::string* dst, uint64_t value);
+extern void PutVarint32(std::string* dst, uint32_t value);
+extern void PutVarint64(std::string* dst, uint64_t value);
+extern void PutLengthPrefixedSlice(std::string* dst, const Slice& value);
+
+// Standard Get... routines parse a value from the beginning of a Slice
+// and advance the slice past the parsed value.
+extern bool GetVarint32(Slice* input, uint32_t* value);
+extern bool GetVarint64(Slice* input, uint64_t* value);
+extern bool GetLengthPrefixedSlice(Slice* input, Slice* result);
+
+// Pointer-based variants of GetVarint... These either store a value
+// in *v and return a pointer just past the parsed value, or return
+// NULL on error. These routines only look at bytes in the range
+// [p..limit-1]
+extern const char* GetVarint32Ptr(const char* p,const char* limit, uint32_t* v);
+extern const char* GetVarint64Ptr(const char* p,const char* limit, uint64_t* v);
+
+// Returns the length of the varint32 or varint64 encoding of "v"
+extern int VarintLength(uint64_t v);
+
+// Lower-level versions of Put... that write directly into a character buffer
+// REQUIRES: dst has enough space for the value being written
+extern void EncodeFixed32(char* dst, uint32_t value);
+extern void EncodeFixed64(char* dst, uint64_t value);
+
+// Lower-level versions of Put... that write directly into a character buffer
+// and return a pointer just past the last byte written.
+// REQUIRES: dst has enough space for the value being written
+extern char* EncodeVarint32(char* dst, uint32_t value);
+extern char* EncodeVarint64(char* dst, uint64_t value);
+
+// Lower-level versions of Get... that read directly from a character buffer
+// without any bounds checking.
+
+inline uint32_t DecodeFixed32(const char* ptr) {
+ if (port::kLittleEndian) {
+ // Load the raw bytes
+ uint32_t result;
+ memcpy(&result, ptr, sizeof(result)); // gcc optimizes this to a plain load
+ return result;
+ } else {
+ return ((static_cast<uint32_t>(ptr[0]))
+ | (static_cast<uint32_t>(ptr[1]) << 8)
+ | (static_cast<uint32_t>(ptr[2]) << 16)
+ | (static_cast<uint32_t>(ptr[3]) << 24));
+ }
+}
+
+inline uint64_t DecodeFixed64(const char* ptr) {
+ if (port::kLittleEndian) {
+ // Load the raw bytes
+ uint64_t result;
+ memcpy(&result, ptr, sizeof(result)); // gcc optimizes this to a plain load
+ return result;
+ } else {
+ uint64_t lo = DecodeFixed32(ptr);
+ uint64_t hi = DecodeFixed32(ptr + 4);
+ return (hi << 32) | lo;
+ }
+}
+
+// Internal routine for use by fallback path of GetVarint32Ptr
+extern const char* GetVarint32PtrFallback(const char* p,
+ const char* limit,
+ uint32_t* value);
+inline const char* GetVarint32Ptr(const char* p,
+ const char* limit,
+ uint32_t* value) {
+ if (p < limit) {
+ uint32_t result = *(reinterpret_cast<const unsigned char*>(p));
+ if ((result & 128) == 0) {
+ *value = result;
+ return p + 1;
+ }
+ }
+ return GetVarint32PtrFallback(p, limit, value);
+}
+
+}
+
+#endif // STORAGE_LEVELDB_UTIL_CODING_H_
diff --git a/util/coding_test.cc b/util/coding_test.cc
new file mode 100644
index 0000000..a8dba04
--- /dev/null
+++ b/util/coding_test.cc
@@ -0,0 +1,173 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "util/coding.h"
+
+#include "util/testharness.h"
+
+namespace leveldb {
+
+class Coding { };
+
+TEST(Coding, Fixed32) {
+ std::string s;
+ for (uint32_t v = 0; v < 100000; v++) {
+ PutFixed32(&s, v);
+ }
+
+ const char* p = s.data();
+ for (uint32_t v = 0; v < 100000; v++) {
+ uint32_t actual = DecodeFixed32(p);
+ ASSERT_EQ(v, actual);
+ p += sizeof(uint32_t);
+ }
+}
+
+TEST(Coding, Fixed64) {
+ std::string s;
+ for (int power = 0; power <= 63; power++) {
+ uint64_t v = static_cast<uint64_t>(1) << power;
+ PutFixed64(&s, v - 1);
+ PutFixed64(&s, v + 0);
+ PutFixed64(&s, v + 1);
+ }
+
+ const char* p = s.data();
+ for (int power = 0; power <= 63; power++) {
+ uint64_t v = static_cast<uint64_t>(1) << power;
+ uint64_t actual;
+ actual = DecodeFixed64(p);
+ ASSERT_EQ(v-1, actual);
+ p += sizeof(uint64_t);
+
+ actual = DecodeFixed64(p);
+ ASSERT_EQ(v+0, actual);
+ p += sizeof(uint64_t);
+
+ actual = DecodeFixed64(p);
+ ASSERT_EQ(v+1, actual);
+ p += sizeof(uint64_t);
+ }
+}
+
+TEST(Coding, Varint32) {
+ std::string s;
+ for (uint32_t i = 0; i < (32 * 32); i++) {
+ uint32_t v = (i / 32) << (i % 32);
+ PutVarint32(&s, v);
+ }
+
+ const char* p = s.data();
+ const char* limit = p + s.size();
+ for (uint32_t i = 0; i < (32 * 32); i++) {
+ uint32_t expected = (i / 32) << (i % 32);
+ uint32_t actual;
+ const char* start = p;
+ p = GetVarint32Ptr(p, limit, &actual);
+ ASSERT_TRUE(p != NULL);
+ ASSERT_EQ(expected, actual);
+ ASSERT_EQ(VarintLength(actual), p - start);
+ }
+ ASSERT_EQ(p, s.data() + s.size());
+}
+
+TEST(Coding, Varint64) {
+ // Construct the list of values to check
+ std::vector<uint64_t> values;
+ // Some special values
+ values.push_back(0);
+ values.push_back(100);
+ values.push_back(~static_cast<uint64_t>(0));
+ values.push_back(~static_cast<uint64_t>(0) - 1);
+ for (uint32_t k = 0; k < 64; k++) {
+ // Test values near powers of two
+ const uint64_t power = 1ull << k;
+ values.push_back(power);
+ values.push_back(power-1);
+ values.push_back(power+1);
+ };
+
+ std::string s;
+ for (int i = 0; i < values.size(); i++) {
+ PutVarint64(&s, values[i]);
+ }
+
+ const char* p = s.data();
+ const char* limit = p + s.size();
+ for (int i = 0; i < values.size(); i++) {
+ ASSERT_TRUE(p < limit);
+ uint64_t actual;
+ const char* start = p;
+ p = GetVarint64Ptr(p, limit, &actual);
+ ASSERT_TRUE(p != NULL);
+ ASSERT_EQ(values[i], actual);
+ ASSERT_EQ(VarintLength(actual), p - start);
+ }
+ ASSERT_EQ(p, limit);
+
+}
+
+TEST(Coding, Varint32Overflow) {
+ uint32_t result;
+ std::string input("\x81\x82\x83\x84\x85\x11");
+ ASSERT_TRUE(GetVarint32Ptr(input.data(), input.data() + input.size(), &result)
+ == NULL);
+}
+
+TEST(Coding, Varint32Truncation) {
+ uint32_t large_value = (1u << 31) + 100;
+ std::string s;
+ PutVarint32(&s, large_value);
+ uint32_t result;
+ for (int len = 0; len < s.size() - 1; len++) {
+ ASSERT_TRUE(GetVarint32Ptr(s.data(), s.data() + len, &result) == NULL);
+ }
+ ASSERT_TRUE(GetVarint32Ptr(s.data(), s.data() + s.size(), &result) != NULL);
+ ASSERT_EQ(large_value, result);
+}
+
+TEST(Coding, Varint64Overflow) {
+ uint64_t result;
+ std::string input("\x81\x82\x83\x84\x85\x81\x82\x83\x84\x85\x11");
+ ASSERT_TRUE(GetVarint64Ptr(input.data(), input.data() + input.size(), &result)
+ == NULL);
+}
+
+TEST(Coding, Varint64Truncation) {
+ uint64_t large_value = (1ull << 63) + 100ull;
+ std::string s;
+ PutVarint64(&s, large_value);
+ uint64_t result;
+ for (int len = 0; len < s.size() - 1; len++) {
+ ASSERT_TRUE(GetVarint64Ptr(s.data(), s.data() + len, &result) == NULL);
+ }
+ ASSERT_TRUE(GetVarint64Ptr(s.data(), s.data() + s.size(), &result) != NULL);
+ ASSERT_EQ(large_value, result);
+}
+
+TEST(Coding, Strings) {
+ std::string s;
+ PutLengthPrefixedSlice(&s, Slice(""));
+ PutLengthPrefixedSlice(&s, Slice("foo"));
+ PutLengthPrefixedSlice(&s, Slice("bar"));
+ PutLengthPrefixedSlice(&s, Slice(std::string(200, 'x')));
+
+ Slice input(s);
+ Slice v;
+ ASSERT_TRUE(GetLengthPrefixedSlice(&input, &v));
+ ASSERT_EQ("", v.ToString());
+ ASSERT_TRUE(GetLengthPrefixedSlice(&input, &v));
+ ASSERT_EQ("foo", v.ToString());
+ ASSERT_TRUE(GetLengthPrefixedSlice(&input, &v));
+ ASSERT_EQ("bar", v.ToString());
+ ASSERT_TRUE(GetLengthPrefixedSlice(&input, &v));
+ ASSERT_EQ(std::string(200, 'x'), v.ToString());
+ ASSERT_EQ("", input.ToString());
+}
+
+}
+
+int main(int argc, char** argv) {
+ return leveldb::test::RunAllTests();
+}
diff --git a/util/comparator.cc b/util/comparator.cc
new file mode 100644
index 0000000..dca3b4d
--- /dev/null
+++ b/util/comparator.cc
@@ -0,0 +1,72 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include <stdint.h>
+#include "include/comparator.h"
+#include "include/slice.h"
+#include "util/logging.h"
+
+namespace leveldb {
+
+Comparator::~Comparator() { }
+
+namespace {
+class BytewiseComparatorImpl : public Comparator {
+ public:
+ BytewiseComparatorImpl() { }
+
+ virtual const char* Name() const {
+ return "leveldb.BytewiseComparator";
+ }
+
+ virtual int Compare(const Slice& a, const Slice& b) const {
+ return a.compare(b);
+ }
+
+ virtual void FindShortestSeparator(
+ std::string* start,
+ const Slice& limit) const {
+ // Find length of common prefix
+ size_t min_length = std::min(start->size(), limit.size());
+ size_t diff_index = 0;
+ while ((diff_index < min_length) &&
+ ((*start)[diff_index] == limit[diff_index])) {
+ diff_index++;
+ }
+
+ if (diff_index >= min_length) {
+ // Do not shorten if one string is a prefix of the other
+ } else {
+ uint8_t diff_byte = static_cast<uint8_t>((*start)[diff_index]);
+ if (diff_byte < static_cast<uint8_t>(0xff) &&
+ diff_byte + 1 < static_cast<uint8_t>(limit[diff_index])) {
+ (*start)[diff_index]++;
+ start->resize(diff_index + 1);
+ assert(Compare(*start, limit) < 0);
+ }
+ }
+ }
+
+ virtual void FindShortSuccessor(std::string* key) const {
+ // Find first character that can be incremented
+ size_t n = key->size();
+ for (int i = 0; i < n; i++) {
+ const uint8_t byte = (*key)[i];
+ if (byte != static_cast<uint8_t>(0xff)) {
+ (*key)[i] = byte + 1;
+ key->resize(i+1);
+ return;
+ }
+ }
+ // *key is a run of 0xffs. Leave it alone.
+ }
+};
+}
+static const BytewiseComparatorImpl bytewise;
+
+const Comparator* BytewiseComparator() {
+ return &bytewise;
+}
+
+}
diff --git a/util/crc32c.cc b/util/crc32c.cc
new file mode 100644
index 0000000..28c2401
--- /dev/null
+++ b/util/crc32c.cc
@@ -0,0 +1,332 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+//
+// A portable implementation of crc32c, optimized to handle
+// four bytes at a time.
+
+#include "util/crc32c.h"
+
+#include <stdint.h>
+#include "util/coding.h"
+
+namespace leveldb {
+namespace crc32c {
+
+static const uint32_t table0_[256] = {
+ 0x00000000, 0xf26b8303, 0xe13b70f7, 0x1350f3f4,
+ 0xc79a971f, 0x35f1141c, 0x26a1e7e8, 0xd4ca64eb,
+ 0x8ad958cf, 0x78b2dbcc, 0x6be22838, 0x9989ab3b,
+ 0x4d43cfd0, 0xbf284cd3, 0xac78bf27, 0x5e133c24,
+ 0x105ec76f, 0xe235446c, 0xf165b798, 0x030e349b,
+ 0xd7c45070, 0x25afd373, 0x36ff2087, 0xc494a384,
+ 0x9a879fa0, 0x68ec1ca3, 0x7bbcef57, 0x89d76c54,
+ 0x5d1d08bf, 0xaf768bbc, 0xbc267848, 0x4e4dfb4b,
+ 0x20bd8ede, 0xd2d60ddd, 0xc186fe29, 0x33ed7d2a,
+ 0xe72719c1, 0x154c9ac2, 0x061c6936, 0xf477ea35,
+ 0xaa64d611, 0x580f5512, 0x4b5fa6e6, 0xb93425e5,
+ 0x6dfe410e, 0x9f95c20d, 0x8cc531f9, 0x7eaeb2fa,
+ 0x30e349b1, 0xc288cab2, 0xd1d83946, 0x23b3ba45,
+ 0xf779deae, 0x05125dad, 0x1642ae59, 0xe4292d5a,
+ 0xba3a117e, 0x4851927d, 0x5b016189, 0xa96ae28a,
+ 0x7da08661, 0x8fcb0562, 0x9c9bf696, 0x6ef07595,
+ 0x417b1dbc, 0xb3109ebf, 0xa0406d4b, 0x522bee48,
+ 0x86e18aa3, 0x748a09a0, 0x67dafa54, 0x95b17957,
+ 0xcba24573, 0x39c9c670, 0x2a993584, 0xd8f2b687,
+ 0x0c38d26c, 0xfe53516f, 0xed03a29b, 0x1f682198,
+ 0x5125dad3, 0xa34e59d0, 0xb01eaa24, 0x42752927,
+ 0x96bf4dcc, 0x64d4cecf, 0x77843d3b, 0x85efbe38,
+ 0xdbfc821c, 0x2997011f, 0x3ac7f2eb, 0xc8ac71e8,
+ 0x1c661503, 0xee0d9600, 0xfd5d65f4, 0x0f36e6f7,
+ 0x61c69362, 0x93ad1061, 0x80fde395, 0x72966096,
+ 0xa65c047d, 0x5437877e, 0x4767748a, 0xb50cf789,
+ 0xeb1fcbad, 0x197448ae, 0x0a24bb5a, 0xf84f3859,
+ 0x2c855cb2, 0xdeeedfb1, 0xcdbe2c45, 0x3fd5af46,
+ 0x7198540d, 0x83f3d70e, 0x90a324fa, 0x62c8a7f9,
+ 0xb602c312, 0x44694011, 0x5739b3e5, 0xa55230e6,
+ 0xfb410cc2, 0x092a8fc1, 0x1a7a7c35, 0xe811ff36,
+ 0x3cdb9bdd, 0xceb018de, 0xdde0eb2a, 0x2f8b6829,
+ 0x82f63b78, 0x709db87b, 0x63cd4b8f, 0x91a6c88c,
+ 0x456cac67, 0xb7072f64, 0xa457dc90, 0x563c5f93,
+ 0x082f63b7, 0xfa44e0b4, 0xe9141340, 0x1b7f9043,
+ 0xcfb5f4a8, 0x3dde77ab, 0x2e8e845f, 0xdce5075c,
+ 0x92a8fc17, 0x60c37f14, 0x73938ce0, 0x81f80fe3,
+ 0x55326b08, 0xa759e80b, 0xb4091bff, 0x466298fc,
+ 0x1871a4d8, 0xea1a27db, 0xf94ad42f, 0x0b21572c,
+ 0xdfeb33c7, 0x2d80b0c4, 0x3ed04330, 0xccbbc033,
+ 0xa24bb5a6, 0x502036a5, 0x4370c551, 0xb11b4652,
+ 0x65d122b9, 0x97baa1ba, 0x84ea524e, 0x7681d14d,
+ 0x2892ed69, 0xdaf96e6a, 0xc9a99d9e, 0x3bc21e9d,
+ 0xef087a76, 0x1d63f975, 0x0e330a81, 0xfc588982,
+ 0xb21572c9, 0x407ef1ca, 0x532e023e, 0xa145813d,
+ 0x758fe5d6, 0x87e466d5, 0x94b49521, 0x66df1622,
+ 0x38cc2a06, 0xcaa7a905, 0xd9f75af1, 0x2b9cd9f2,
+ 0xff56bd19, 0x0d3d3e1a, 0x1e6dcdee, 0xec064eed,
+ 0xc38d26c4, 0x31e6a5c7, 0x22b65633, 0xd0ddd530,
+ 0x0417b1db, 0xf67c32d8, 0xe52cc12c, 0x1747422f,
+ 0x49547e0b, 0xbb3ffd08, 0xa86f0efc, 0x5a048dff,
+ 0x8ecee914, 0x7ca56a17, 0x6ff599e3, 0x9d9e1ae0,
+ 0xd3d3e1ab, 0x21b862a8, 0x32e8915c, 0xc083125f,
+ 0x144976b4, 0xe622f5b7, 0xf5720643, 0x07198540,
+ 0x590ab964, 0xab613a67, 0xb831c993, 0x4a5a4a90,
+ 0x9e902e7b, 0x6cfbad78, 0x7fab5e8c, 0x8dc0dd8f,
+ 0xe330a81a, 0x115b2b19, 0x020bd8ed, 0xf0605bee,
+ 0x24aa3f05, 0xd6c1bc06, 0xc5914ff2, 0x37faccf1,
+ 0x69e9f0d5, 0x9b8273d6, 0x88d28022, 0x7ab90321,
+ 0xae7367ca, 0x5c18e4c9, 0x4f48173d, 0xbd23943e,
+ 0xf36e6f75, 0x0105ec76, 0x12551f82, 0xe03e9c81,
+ 0x34f4f86a, 0xc69f7b69, 0xd5cf889d, 0x27a40b9e,
+ 0x79b737ba, 0x8bdcb4b9, 0x988c474d, 0x6ae7c44e,
+ 0xbe2da0a5, 0x4c4623a6, 0x5f16d052, 0xad7d5351
+};
+static const uint32_t table1_[256] = {
+ 0x00000000, 0x13a29877, 0x274530ee, 0x34e7a899,
+ 0x4e8a61dc, 0x5d28f9ab, 0x69cf5132, 0x7a6dc945,
+ 0x9d14c3b8, 0x8eb65bcf, 0xba51f356, 0xa9f36b21,
+ 0xd39ea264, 0xc03c3a13, 0xf4db928a, 0xe7790afd,
+ 0x3fc5f181, 0x2c6769f6, 0x1880c16f, 0x0b225918,
+ 0x714f905d, 0x62ed082a, 0x560aa0b3, 0x45a838c4,
+ 0xa2d13239, 0xb173aa4e, 0x859402d7, 0x96369aa0,
+ 0xec5b53e5, 0xfff9cb92, 0xcb1e630b, 0xd8bcfb7c,
+ 0x7f8be302, 0x6c297b75, 0x58ced3ec, 0x4b6c4b9b,
+ 0x310182de, 0x22a31aa9, 0x1644b230, 0x05e62a47,
+ 0xe29f20ba, 0xf13db8cd, 0xc5da1054, 0xd6788823,
+ 0xac154166, 0xbfb7d911, 0x8b507188, 0x98f2e9ff,
+ 0x404e1283, 0x53ec8af4, 0x670b226d, 0x74a9ba1a,
+ 0x0ec4735f, 0x1d66eb28, 0x298143b1, 0x3a23dbc6,
+ 0xdd5ad13b, 0xcef8494c, 0xfa1fe1d5, 0xe9bd79a2,
+ 0x93d0b0e7, 0x80722890, 0xb4958009, 0xa737187e,
+ 0xff17c604, 0xecb55e73, 0xd852f6ea, 0xcbf06e9d,
+ 0xb19da7d8, 0xa23f3faf, 0x96d89736, 0x857a0f41,
+ 0x620305bc, 0x71a19dcb, 0x45463552, 0x56e4ad25,
+ 0x2c896460, 0x3f2bfc17, 0x0bcc548e, 0x186eccf9,
+ 0xc0d23785, 0xd370aff2, 0xe797076b, 0xf4359f1c,
+ 0x8e585659, 0x9dface2e, 0xa91d66b7, 0xbabffec0,
+ 0x5dc6f43d, 0x4e646c4a, 0x7a83c4d3, 0x69215ca4,
+ 0x134c95e1, 0x00ee0d96, 0x3409a50f, 0x27ab3d78,
+ 0x809c2506, 0x933ebd71, 0xa7d915e8, 0xb47b8d9f,
+ 0xce1644da, 0xddb4dcad, 0xe9537434, 0xfaf1ec43,
+ 0x1d88e6be, 0x0e2a7ec9, 0x3acdd650, 0x296f4e27,
+ 0x53028762, 0x40a01f15, 0x7447b78c, 0x67e52ffb,
+ 0xbf59d487, 0xacfb4cf0, 0x981ce469, 0x8bbe7c1e,
+ 0xf1d3b55b, 0xe2712d2c, 0xd69685b5, 0xc5341dc2,
+ 0x224d173f, 0x31ef8f48, 0x050827d1, 0x16aabfa6,
+ 0x6cc776e3, 0x7f65ee94, 0x4b82460d, 0x5820de7a,
+ 0xfbc3faf9, 0xe861628e, 0xdc86ca17, 0xcf245260,
+ 0xb5499b25, 0xa6eb0352, 0x920cabcb, 0x81ae33bc,
+ 0x66d73941, 0x7575a136, 0x419209af, 0x523091d8,
+ 0x285d589d, 0x3bffc0ea, 0x0f186873, 0x1cbaf004,
+ 0xc4060b78, 0xd7a4930f, 0xe3433b96, 0xf0e1a3e1,
+ 0x8a8c6aa4, 0x992ef2d3, 0xadc95a4a, 0xbe6bc23d,
+ 0x5912c8c0, 0x4ab050b7, 0x7e57f82e, 0x6df56059,
+ 0x1798a91c, 0x043a316b, 0x30dd99f2, 0x237f0185,
+ 0x844819fb, 0x97ea818c, 0xa30d2915, 0xb0afb162,
+ 0xcac27827, 0xd960e050, 0xed8748c9, 0xfe25d0be,
+ 0x195cda43, 0x0afe4234, 0x3e19eaad, 0x2dbb72da,
+ 0x57d6bb9f, 0x447423e8, 0x70938b71, 0x63311306,
+ 0xbb8de87a, 0xa82f700d, 0x9cc8d894, 0x8f6a40e3,
+ 0xf50789a6, 0xe6a511d1, 0xd242b948, 0xc1e0213f,
+ 0x26992bc2, 0x353bb3b5, 0x01dc1b2c, 0x127e835b,
+ 0x68134a1e, 0x7bb1d269, 0x4f567af0, 0x5cf4e287,
+ 0x04d43cfd, 0x1776a48a, 0x23910c13, 0x30339464,
+ 0x4a5e5d21, 0x59fcc556, 0x6d1b6dcf, 0x7eb9f5b8,
+ 0x99c0ff45, 0x8a626732, 0xbe85cfab, 0xad2757dc,
+ 0xd74a9e99, 0xc4e806ee, 0xf00fae77, 0xe3ad3600,
+ 0x3b11cd7c, 0x28b3550b, 0x1c54fd92, 0x0ff665e5,
+ 0x759baca0, 0x663934d7, 0x52de9c4e, 0x417c0439,
+ 0xa6050ec4, 0xb5a796b3, 0x81403e2a, 0x92e2a65d,
+ 0xe88f6f18, 0xfb2df76f, 0xcfca5ff6, 0xdc68c781,
+ 0x7b5fdfff, 0x68fd4788, 0x5c1aef11, 0x4fb87766,
+ 0x35d5be23, 0x26772654, 0x12908ecd, 0x013216ba,
+ 0xe64b1c47, 0xf5e98430, 0xc10e2ca9, 0xd2acb4de,
+ 0xa8c17d9b, 0xbb63e5ec, 0x8f844d75, 0x9c26d502,
+ 0x449a2e7e, 0x5738b609, 0x63df1e90, 0x707d86e7,
+ 0x0a104fa2, 0x19b2d7d5, 0x2d557f4c, 0x3ef7e73b,
+ 0xd98eedc6, 0xca2c75b1, 0xfecbdd28, 0xed69455f,
+ 0x97048c1a, 0x84a6146d, 0xb041bcf4, 0xa3e32483
+};
+static const uint32_t table2_[256] = {
+ 0x00000000, 0xa541927e, 0x4f6f520d, 0xea2ec073,
+ 0x9edea41a, 0x3b9f3664, 0xd1b1f617, 0x74f06469,
+ 0x38513ec5, 0x9d10acbb, 0x773e6cc8, 0xd27ffeb6,
+ 0xa68f9adf, 0x03ce08a1, 0xe9e0c8d2, 0x4ca15aac,
+ 0x70a27d8a, 0xd5e3eff4, 0x3fcd2f87, 0x9a8cbdf9,
+ 0xee7cd990, 0x4b3d4bee, 0xa1138b9d, 0x045219e3,
+ 0x48f3434f, 0xedb2d131, 0x079c1142, 0xa2dd833c,
+ 0xd62de755, 0x736c752b, 0x9942b558, 0x3c032726,
+ 0xe144fb14, 0x4405696a, 0xae2ba919, 0x0b6a3b67,
+ 0x7f9a5f0e, 0xdadbcd70, 0x30f50d03, 0x95b49f7d,
+ 0xd915c5d1, 0x7c5457af, 0x967a97dc, 0x333b05a2,
+ 0x47cb61cb, 0xe28af3b5, 0x08a433c6, 0xade5a1b8,
+ 0x91e6869e, 0x34a714e0, 0xde89d493, 0x7bc846ed,
+ 0x0f382284, 0xaa79b0fa, 0x40577089, 0xe516e2f7,
+ 0xa9b7b85b, 0x0cf62a25, 0xe6d8ea56, 0x43997828,
+ 0x37691c41, 0x92288e3f, 0x78064e4c, 0xdd47dc32,
+ 0xc76580d9, 0x622412a7, 0x880ad2d4, 0x2d4b40aa,
+ 0x59bb24c3, 0xfcfab6bd, 0x16d476ce, 0xb395e4b0,
+ 0xff34be1c, 0x5a752c62, 0xb05bec11, 0x151a7e6f,
+ 0x61ea1a06, 0xc4ab8878, 0x2e85480b, 0x8bc4da75,
+ 0xb7c7fd53, 0x12866f2d, 0xf8a8af5e, 0x5de93d20,
+ 0x29195949, 0x8c58cb37, 0x66760b44, 0xc337993a,
+ 0x8f96c396, 0x2ad751e8, 0xc0f9919b, 0x65b803e5,
+ 0x1148678c, 0xb409f5f2, 0x5e273581, 0xfb66a7ff,
+ 0x26217bcd, 0x8360e9b3, 0x694e29c0, 0xcc0fbbbe,
+ 0xb8ffdfd7, 0x1dbe4da9, 0xf7908dda, 0x52d11fa4,
+ 0x1e704508, 0xbb31d776, 0x511f1705, 0xf45e857b,
+ 0x80aee112, 0x25ef736c, 0xcfc1b31f, 0x6a802161,
+ 0x56830647, 0xf3c29439, 0x19ec544a, 0xbcadc634,
+ 0xc85da25d, 0x6d1c3023, 0x8732f050, 0x2273622e,
+ 0x6ed23882, 0xcb93aafc, 0x21bd6a8f, 0x84fcf8f1,
+ 0xf00c9c98, 0x554d0ee6, 0xbf63ce95, 0x1a225ceb,
+ 0x8b277743, 0x2e66e53d, 0xc448254e, 0x6109b730,
+ 0x15f9d359, 0xb0b84127, 0x5a968154, 0xffd7132a,
+ 0xb3764986, 0x1637dbf8, 0xfc191b8b, 0x595889f5,
+ 0x2da8ed9c, 0x88e97fe2, 0x62c7bf91, 0xc7862def,
+ 0xfb850ac9, 0x5ec498b7, 0xb4ea58c4, 0x11abcaba,
+ 0x655baed3, 0xc01a3cad, 0x2a34fcde, 0x8f756ea0,
+ 0xc3d4340c, 0x6695a672, 0x8cbb6601, 0x29faf47f,
+ 0x5d0a9016, 0xf84b0268, 0x1265c21b, 0xb7245065,
+ 0x6a638c57, 0xcf221e29, 0x250cde5a, 0x804d4c24,
+ 0xf4bd284d, 0x51fcba33, 0xbbd27a40, 0x1e93e83e,
+ 0x5232b292, 0xf77320ec, 0x1d5de09f, 0xb81c72e1,
+ 0xccec1688, 0x69ad84f6, 0x83834485, 0x26c2d6fb,
+ 0x1ac1f1dd, 0xbf8063a3, 0x55aea3d0, 0xf0ef31ae,
+ 0x841f55c7, 0x215ec7b9, 0xcb7007ca, 0x6e3195b4,
+ 0x2290cf18, 0x87d15d66, 0x6dff9d15, 0xc8be0f6b,
+ 0xbc4e6b02, 0x190ff97c, 0xf321390f, 0x5660ab71,
+ 0x4c42f79a, 0xe90365e4, 0x032da597, 0xa66c37e9,
+ 0xd29c5380, 0x77ddc1fe, 0x9df3018d, 0x38b293f3,
+ 0x7413c95f, 0xd1525b21, 0x3b7c9b52, 0x9e3d092c,
+ 0xeacd6d45, 0x4f8cff3b, 0xa5a23f48, 0x00e3ad36,
+ 0x3ce08a10, 0x99a1186e, 0x738fd81d, 0xd6ce4a63,
+ 0xa23e2e0a, 0x077fbc74, 0xed517c07, 0x4810ee79,
+ 0x04b1b4d5, 0xa1f026ab, 0x4bdee6d8, 0xee9f74a6,
+ 0x9a6f10cf, 0x3f2e82b1, 0xd50042c2, 0x7041d0bc,
+ 0xad060c8e, 0x08479ef0, 0xe2695e83, 0x4728ccfd,
+ 0x33d8a894, 0x96993aea, 0x7cb7fa99, 0xd9f668e7,
+ 0x9557324b, 0x3016a035, 0xda386046, 0x7f79f238,
+ 0x0b899651, 0xaec8042f, 0x44e6c45c, 0xe1a75622,
+ 0xdda47104, 0x78e5e37a, 0x92cb2309, 0x378ab177,
+ 0x437ad51e, 0xe63b4760, 0x0c158713, 0xa954156d,
+ 0xe5f54fc1, 0x40b4ddbf, 0xaa9a1dcc, 0x0fdb8fb2,
+ 0x7b2bebdb, 0xde6a79a5, 0x3444b9d6, 0x91052ba8
+};
+static const uint32_t table3_[256] = {
+ 0x00000000, 0xdd45aab8, 0xbf672381, 0x62228939,
+ 0x7b2231f3, 0xa6679b4b, 0xc4451272, 0x1900b8ca,
+ 0xf64463e6, 0x2b01c95e, 0x49234067, 0x9466eadf,
+ 0x8d665215, 0x5023f8ad, 0x32017194, 0xef44db2c,
+ 0xe964b13d, 0x34211b85, 0x560392bc, 0x8b463804,
+ 0x924680ce, 0x4f032a76, 0x2d21a34f, 0xf06409f7,
+ 0x1f20d2db, 0xc2657863, 0xa047f15a, 0x7d025be2,
+ 0x6402e328, 0xb9474990, 0xdb65c0a9, 0x06206a11,
+ 0xd725148b, 0x0a60be33, 0x6842370a, 0xb5079db2,
+ 0xac072578, 0x71428fc0, 0x136006f9, 0xce25ac41,
+ 0x2161776d, 0xfc24ddd5, 0x9e0654ec, 0x4343fe54,
+ 0x5a43469e, 0x8706ec26, 0xe524651f, 0x3861cfa7,
+ 0x3e41a5b6, 0xe3040f0e, 0x81268637, 0x5c632c8f,
+ 0x45639445, 0x98263efd, 0xfa04b7c4, 0x27411d7c,
+ 0xc805c650, 0x15406ce8, 0x7762e5d1, 0xaa274f69,
+ 0xb327f7a3, 0x6e625d1b, 0x0c40d422, 0xd1057e9a,
+ 0xaba65fe7, 0x76e3f55f, 0x14c17c66, 0xc984d6de,
+ 0xd0846e14, 0x0dc1c4ac, 0x6fe34d95, 0xb2a6e72d,
+ 0x5de23c01, 0x80a796b9, 0xe2851f80, 0x3fc0b538,
+ 0x26c00df2, 0xfb85a74a, 0x99a72e73, 0x44e284cb,
+ 0x42c2eeda, 0x9f874462, 0xfda5cd5b, 0x20e067e3,
+ 0x39e0df29, 0xe4a57591, 0x8687fca8, 0x5bc25610,
+ 0xb4868d3c, 0x69c32784, 0x0be1aebd, 0xd6a40405,
+ 0xcfa4bccf, 0x12e11677, 0x70c39f4e, 0xad8635f6,
+ 0x7c834b6c, 0xa1c6e1d4, 0xc3e468ed, 0x1ea1c255,
+ 0x07a17a9f, 0xdae4d027, 0xb8c6591e, 0x6583f3a6,
+ 0x8ac7288a, 0x57828232, 0x35a00b0b, 0xe8e5a1b3,
+ 0xf1e51979, 0x2ca0b3c1, 0x4e823af8, 0x93c79040,
+ 0x95e7fa51, 0x48a250e9, 0x2a80d9d0, 0xf7c57368,
+ 0xeec5cba2, 0x3380611a, 0x51a2e823, 0x8ce7429b,
+ 0x63a399b7, 0xbee6330f, 0xdcc4ba36, 0x0181108e,
+ 0x1881a844, 0xc5c402fc, 0xa7e68bc5, 0x7aa3217d,
+ 0x52a0c93f, 0x8fe56387, 0xedc7eabe, 0x30824006,
+ 0x2982f8cc, 0xf4c75274, 0x96e5db4d, 0x4ba071f5,
+ 0xa4e4aad9, 0x79a10061, 0x1b838958, 0xc6c623e0,
+ 0xdfc69b2a, 0x02833192, 0x60a1b8ab, 0xbde41213,
+ 0xbbc47802, 0x6681d2ba, 0x04a35b83, 0xd9e6f13b,
+ 0xc0e649f1, 0x1da3e349, 0x7f816a70, 0xa2c4c0c8,
+ 0x4d801be4, 0x90c5b15c, 0xf2e73865, 0x2fa292dd,
+ 0x36a22a17, 0xebe780af, 0x89c50996, 0x5480a32e,
+ 0x8585ddb4, 0x58c0770c, 0x3ae2fe35, 0xe7a7548d,
+ 0xfea7ec47, 0x23e246ff, 0x41c0cfc6, 0x9c85657e,
+ 0x73c1be52, 0xae8414ea, 0xcca69dd3, 0x11e3376b,
+ 0x08e38fa1, 0xd5a62519, 0xb784ac20, 0x6ac10698,
+ 0x6ce16c89, 0xb1a4c631, 0xd3864f08, 0x0ec3e5b0,
+ 0x17c35d7a, 0xca86f7c2, 0xa8a47efb, 0x75e1d443,
+ 0x9aa50f6f, 0x47e0a5d7, 0x25c22cee, 0xf8878656,
+ 0xe1873e9c, 0x3cc29424, 0x5ee01d1d, 0x83a5b7a5,
+ 0xf90696d8, 0x24433c60, 0x4661b559, 0x9b241fe1,
+ 0x8224a72b, 0x5f610d93, 0x3d4384aa, 0xe0062e12,
+ 0x0f42f53e, 0xd2075f86, 0xb025d6bf, 0x6d607c07,
+ 0x7460c4cd, 0xa9256e75, 0xcb07e74c, 0x16424df4,
+ 0x106227e5, 0xcd278d5d, 0xaf050464, 0x7240aedc,
+ 0x6b401616, 0xb605bcae, 0xd4273597, 0x09629f2f,
+ 0xe6264403, 0x3b63eebb, 0x59416782, 0x8404cd3a,
+ 0x9d0475f0, 0x4041df48, 0x22635671, 0xff26fcc9,
+ 0x2e238253, 0xf36628eb, 0x9144a1d2, 0x4c010b6a,
+ 0x5501b3a0, 0x88441918, 0xea669021, 0x37233a99,
+ 0xd867e1b5, 0x05224b0d, 0x6700c234, 0xba45688c,
+ 0xa345d046, 0x7e007afe, 0x1c22f3c7, 0xc167597f,
+ 0xc747336e, 0x1a0299d6, 0x782010ef, 0xa565ba57,
+ 0xbc65029d, 0x6120a825, 0x0302211c, 0xde478ba4,
+ 0x31035088, 0xec46fa30, 0x8e647309, 0x5321d9b1,
+ 0x4a21617b, 0x9764cbc3, 0xf54642fa, 0x2803e842
+};
+
+// Used to fetch a naturally-aligned 32-bit word in little endian byte-order
+static inline uint32_t LE_LOAD32(const uint8_t *p) {
+ return DecodeFixed32(reinterpret_cast<const char*>(p));
+}
+
+uint32_t Extend(uint32_t crc, const char* buf, size_t size) {
+ const uint8_t *p = reinterpret_cast<const uint8_t *>(buf);
+ const uint8_t *e = p + size;
+ uint32_t l = crc ^ 0xffffffffu;
+
+#define STEP1 do { \
+ int c = (l & 0xff) ^ *p++; \
+ l = table0_[c] ^ (l >> 8); \
+} while (0)
+#define STEP4 do { \
+ uint32_t c = l ^ LE_LOAD32(p); \
+ p += 4; \
+ l = table3_[c & 0xff] ^ \
+ table2_[(c >> 8) & 0xff] ^ \
+ table1_[(c >> 16) & 0xff] ^ \
+ table0_[c >> 24]; \
+} while (0)
+
+ // Point x at first 4-byte aligned byte in string. This might be
+ // just past the end of the string.
+ const uintptr_t pval = reinterpret_cast<uintptr_t>(p);
+ const uint8_t* x = reinterpret_cast<const uint8_t*>(((pval + 3) >> 2) << 2);
+ if (x <= e) {
+ // Process bytes until finished or p is 4-byte aligned
+ while (p != x) {
+ STEP1;
+ }
+ }
+ // Process bytes 16 at a time
+ while ((e-p) >= 16) {
+ STEP4; STEP4; STEP4; STEP4;
+ }
+ // Process bytes 4 at a time
+ while ((e-p) >= 4) {
+ STEP4;
+ }
+ // Process the last few bytes
+ while (p != e) {
+ STEP1;
+ }
+#undef STEP4
+#undef STEP1
+ return l ^ 0xffffffffu;
+}
+
+}
+}
diff --git a/util/crc32c.h b/util/crc32c.h
new file mode 100644
index 0000000..938d8ff
--- /dev/null
+++ b/util/crc32c.h
@@ -0,0 +1,45 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#ifndef STORAGE_LEVELDB_UTIL_CRC32C_H_
+#define STORAGE_LEVELDB_UTIL_CRC32C_H_
+
+#include <stddef.h>
+#include <stdint.h>
+
+namespace leveldb {
+namespace crc32c {
+
+// Return the crc32c of concat(A, data[0,n-1]) where init_crc is the
+// crc32c of some string A. Extend() is often used to maintain the
+// crc32c of a stream of data.
+extern uint32_t Extend(uint32_t init_crc, const char* data, size_t n);
+
+// Return the crc32c of data[0,n-1]
+inline uint32_t Value(const char* data, size_t n) {
+ return Extend(0, data, n);
+}
+
+static const uint32_t kMaskDelta = 0xa282ead8ul;
+
+// Return a masked representation of crc.
+//
+// Motivation: it is problematic to compute the CRC of a string that
+// contains embedded CRCs. Therefore we recommend that CRCs stored
+// somewhere (e.g., in files) should be masked before being stored.
+inline uint32_t Mask(uint32_t crc) {
+ // Rotate right by 15 bits and add a constant.
+ return ((crc >> 15) | (crc << 17)) + kMaskDelta;
+}
+
+// Return the crc whose masked representation is masked_crc.
+inline uint32_t Unmask(uint32_t masked_crc) {
+ uint32_t rot = masked_crc - kMaskDelta;
+ return ((rot >> 17) | (rot << 15));
+}
+
+}
+}
+
+#endif // STORAGE_LEVELDB_UTIL_CRC32C_H_
diff --git a/util/crc32c_test.cc b/util/crc32c_test.cc
new file mode 100644
index 0000000..a7fc758
--- /dev/null
+++ b/util/crc32c_test.cc
@@ -0,0 +1,86 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "util/crc32c.h"
+#include "util/testharness.h"
+
+namespace leveldb {
+namespace crc32c {
+
+class CRC { };
+
+TEST(CRC, StandardResults) {
+ // From rfc3720 section B.4.
+ char buf[32];
+
+ memset(buf, 0, sizeof(buf));
+ ASSERT_EQ(0x8a9136aa, Value(buf, sizeof(buf)));
+
+ memset(buf, 0xff, sizeof(buf));
+ ASSERT_EQ(0x62a8ab43, Value(buf, sizeof(buf)));
+
+ for (int i = 0; i < 32; i++) {
+ buf[i] = i;
+ }
+ ASSERT_EQ(0x46dd794e, Value(buf, sizeof(buf)));
+
+ for (int i = 0; i < 32; i++) {
+ buf[i] = 31 - i;
+ }
+ ASSERT_EQ(0x113fdb5c, Value(buf, sizeof(buf)));
+
+ unsigned char data[48] = {
+ 0x01, 0xc0, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00,
+ 0x14, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x04, 0x00,
+ 0x00, 0x00, 0x00, 0x14,
+ 0x00, 0x00, 0x00, 0x18,
+ 0x28, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00,
+ 0x02, 0x00, 0x00, 0x00,
+ 0x00, 0x00, 0x00, 0x00,
+ };
+ ASSERT_EQ(0xd9963a56, Value(reinterpret_cast<char*>(data), sizeof(data)));
+}
+
+TEST(CRC, Values) {
+ ASSERT_NE(Value("a", 1), Value("foo", 3));
+}
+
+TEST(CRC, Extend) {
+ ASSERT_EQ(Value("hello world", 11),
+ Extend(Value("hello ", 6), "world", 5));
+}
+
+TEST(CRC, Mask) {
+ uint32_t crc = Value("foo", 3);
+ ASSERT_NE(crc, Mask(crc));
+ ASSERT_NE(crc, Mask(Mask(crc)));
+ ASSERT_EQ(crc, Unmask(Mask(crc)));
+ ASSERT_EQ(crc, Unmask(Unmask(Mask(Mask(crc)))));
+}
+
+TEST(CRC, Benchmark) {
+ std::string data(1048576 * 100, 'x');
+ double start = Env::Default()->NowMicros() * 1e-6;
+ static const int kIters = 10;
+ uint32_t crc = 0;
+ for (int i = 0; i < kIters; i++) {
+ crc |= Value(data.data(), data.size());
+ }
+ double finish = Env::Default()->NowMicros() * 1e-6;
+ double mb = (static_cast<long long int>(data.size()) * kIters) / 1048576.0;
+ fprintf(stderr, "CRC %0.0f MB: %.3f secs; %.1f MB/s, crc=0x%08x\n",
+ mb, (finish - start), mb / (finish - start), crc);
+}
+
+}
+}
+
+int main(int argc, char** argv) {
+ return leveldb::test::RunAllTests();
+}
diff --git a/util/env.cc b/util/env.cc
new file mode 100644
index 0000000..3c2ca89
--- /dev/null
+++ b/util/env.cc
@@ -0,0 +1,77 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "include/env.h"
+
+namespace leveldb {
+
+Env::~Env() {
+}
+
+SequentialFile::~SequentialFile() {
+}
+
+RandomAccessFile::~RandomAccessFile() {
+}
+
+WritableFile::~WritableFile() {
+}
+
+FileLock::~FileLock() {
+}
+
+void Log(Env* env, WritableFile* info_log, const char* format, ...) {
+ va_list ap;
+ va_start(ap, format);
+ env->Logv(info_log, format, ap);
+ va_end(ap);
+}
+
+Status WriteStringToFile(Env* env, const Slice& data,
+ const std::string& fname) {
+ WritableFile* file;
+ Status s = env->NewWritableFile(fname, &file);
+ if (!s.ok()) {
+ return s;
+ }
+ s = file->Append(data);
+ if (s.ok()) {
+ s = file->Close();
+ }
+ delete file; // Will auto-close if we did not close above
+ if (!s.ok()) {
+ env->DeleteFile(fname);
+ }
+ return s;
+}
+
+Status ReadFileToString(Env* env, const std::string& fname, std::string* data) {
+ data->clear();
+ SequentialFile* file;
+ Status s = env->NewSequentialFile(fname, &file);
+ if (!s.ok()) {
+ return s;
+ }
+ static const int kBufferSize = 8192;
+ char* space = new char[kBufferSize];
+ while (true) {
+ Slice fragment;
+ s = file->Read(kBufferSize, &fragment, space);
+ if (!s.ok()) {
+ break;
+ }
+ data->append(fragment.data(), fragment.size());
+ if (fragment.empty()) {
+ break;
+ }
+ }
+ delete[] space;
+ delete file;
+ return s;
+}
+
+EnvWrapper::~EnvWrapper() {
+}
+
+}
diff --git a/util/env_chromium.cc b/util/env_chromium.cc
new file mode 100644
index 0000000..e39ac71
--- /dev/null
+++ b/util/env_chromium.cc
@@ -0,0 +1,608 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include <deque>
+#include <errno.h>
+#include <stdio.h>
+#include "base/at_exit.h"
+#include "base/file_path.h"
+#include "base/file_util.h"
+#include "base/lazy_instance.h"
+#include "base/message_loop.h"
+#include "base/platform_file.h"
+#include "base/process_util.h"
+#include "base/ref_counted.h"
+#include "base/synchronization/lock.h"
+#include "base/sys_info.h"
+#include "base/task.h"
+#include "base/threading/platform_thread.h"
+#include "base/threading/thread.h"
+#include "base/utf_string_conversions.h"
+#include "include/env.h"
+#include "include/slice.h"
+#include "port/port.h"
+#include "util/logging.h"
+
+#if defined(OS_WIN)
+#include <io.h>
+#include "base/win/win_util.h"
+#endif
+
+#if defined(OS_MACOSX) || defined(OS_WIN)
+// The following are glibc-specific
+extern "C" {
+size_t fread_unlocked(void *ptr, size_t size, size_t n, FILE *file) {
+ return fread(ptr, size, n, file);
+}
+
+size_t fwrite_unlocked(const void *ptr, size_t size, size_t n, FILE *file) {
+ return fwrite(ptr, size, n, file);
+}
+
+int fflush_unlocked(FILE *file) {
+ return fflush(file);
+}
+
+int fdatasync(int fildes) {
+#if defined(OS_WIN)
+ return _commit(fildes);
+#else
+ return fsync(fildes);
+#endif
+}
+}
+#endif
+
+namespace leveldb {
+
+namespace {
+
+class Thread;
+
+::FilePath CreateFilePath(const std::string& file_path) {
+#if defined(OS_WIN)
+ return FilePath(UTF8ToUTF16(file_path));
+#else
+ return FilePath(file_path);
+#endif
+}
+
+std::string FilePathToString(const ::FilePath& file_path) {
+#if defined(OS_WIN)
+ return UTF16ToUTF8(file_path.value());
+#else
+ return file_path.value();
+#endif
+}
+
+// TODO(jorlow): This should be moved into Chromium's base.
+const char* PlatformFileErrorString(const ::base::PlatformFileError& error) {
+ switch (error) {
+ case ::base::PLATFORM_FILE_ERROR_FAILED:
+ return "Opening file failed.";
+ case ::base::PLATFORM_FILE_ERROR_IN_USE:
+ return "File currently in use.";
+ case ::base::PLATFORM_FILE_ERROR_EXISTS:
+ return "File already exists.";
+ case ::base::PLATFORM_FILE_ERROR_NOT_FOUND:
+ return "File not found.";
+ case ::base::PLATFORM_FILE_ERROR_ACCESS_DENIED:
+ return "Access denied.";
+ case ::base::PLATFORM_FILE_ERROR_TOO_MANY_OPENED:
+ return "Too many files open.";
+ case ::base::PLATFORM_FILE_ERROR_NO_MEMORY:
+ return "Out of memory.";
+ case ::base::PLATFORM_FILE_ERROR_NO_SPACE:
+ return "No space left on drive.";
+ case ::base::PLATFORM_FILE_ERROR_NOT_A_DIRECTORY:
+ return "Not a directory.";
+ case ::base::PLATFORM_FILE_ERROR_INVALID_OPERATION:
+ return "Invalid operation.";
+ case ::base::PLATFORM_FILE_ERROR_SECURITY:
+ return "Security error.";
+ case ::base::PLATFORM_FILE_ERROR_ABORT:
+ return "File operation aborted.";
+ case ::base::PLATFORM_FILE_ERROR_NOT_A_FILE:
+ return "The supplied path was not a file.";
+ case ::base::PLATFORM_FILE_ERROR_NOT_EMPTY:
+ return "The file was not empty.";
+ }
+ NOTIMPLEMENTED();
+ return "Unknown error.";
+}
+
+class ChromiumSequentialFile: public SequentialFile {
+ private:
+ std::string filename_;
+ FILE* file_;
+
+ public:
+ ChromiumSequentialFile(const std::string& fname, FILE* f)
+ : filename_(fname), file_(f) { }
+ virtual ~ChromiumSequentialFile() { fclose(file_); }
+
+ virtual Status Read(size_t n, Slice* result, char* scratch) {
+ Status s;
+ size_t r = fread_unlocked(scratch, 1, n, file_);
+ *result = Slice(scratch, r);
+ if (r < n) {
+ if (feof(file_)) {
+ // We leave status as ok if we hit the end of the file
+ } else {
+ // A partial read with an error: return a non-ok status
+ s = Status::IOError(filename_, strerror(errno));
+ }
+ }
+ return s;
+ }
+};
+
+class ChromiumRandomAccessFile: public RandomAccessFile {
+ private:
+ std::string filename_;
+ uint64_t size_;
+ ::base::PlatformFile file_;
+
+ public:
+ ChromiumRandomAccessFile(const std::string& fname, uint64_t size,
+ ::base::PlatformFile file)
+ : filename_(fname), size_(size), file_(file) { }
+ virtual ~ChromiumRandomAccessFile() { ::base::ClosePlatformFile(file_); }
+
+ virtual uint64_t Size() const { return size_; }
+
+ virtual Status Read(uint64_t offset, size_t n, Slice* result,
+ char* scratch) const {
+ Status s;
+ int r = ::base::ReadPlatformFile(file_, offset, scratch, n);
+ *result = Slice(scratch, (r < 0) ? 0 : r);
+ if (r < 0) {
+ // An error: return a non-ok status
+ s = Status::IOError(filename_, "Could not preform read");
+ }
+ return s;
+ }
+};
+
+class ChromiumWritableFile : public WritableFile {
+ private:
+ std::string filename_;
+ FILE* file_;
+
+ public:
+ ChromiumWritableFile(const std::string& fname, FILE* f)
+ : filename_(fname), file_(f) { }
+
+ ~ChromiumWritableFile() {
+ if (file_ != NULL) {
+ // Ignoring any potential errors
+ fclose(file_);
+ }
+ }
+
+ virtual Status Append(const Slice& data) {
+ size_t r = fwrite_unlocked(data.data(), 1, data.size(), file_);
+ Status result;
+ if (r != data.size()) {
+ result = Status::IOError(filename_, strerror(errno));
+ }
+ return result;
+ }
+
+ virtual Status Close() {
+ Status result;
+ if (fclose(file_) != 0) {
+ result = Status::IOError(filename_, strerror(errno));
+ }
+ file_ = NULL;
+ return result;
+ }
+
+ virtual Status Flush() {
+ Status result;
+ if (fflush_unlocked(file_) != 0) {
+ result = Status::IOError(filename_, strerror(errno));
+ }
+ return result;
+ }
+
+ virtual Status Sync() {
+ Status result;
+ if ((fflush_unlocked(file_) != 0) ||
+ (fdatasync(fileno(file_)) != 0)) {
+ result = Status::IOError(filename_, strerror(errno));
+ }
+ return result;
+ }
+};
+
+class ChromiumFileLock : public FileLock {
+ public:
+ ::base::PlatformFile file_;
+};
+
+class ChromiumEnv : public Env {
+ public:
+ ChromiumEnv();
+ virtual ~ChromiumEnv() {
+ fprintf(stderr, "Destroying Env::Default()\n");
+ exit(1);
+ }
+
+ virtual Status NewSequentialFile(const std::string& fname,
+ SequentialFile** result) {
+ FILE* f = fopen(fname.c_str(), "rb");
+ if (f == NULL) {
+ *result = NULL;
+ return Status::IOError(fname, strerror(errno));
+ } else {
+ *result = new ChromiumSequentialFile(fname, f);
+ return Status::OK();
+ }
+ }
+
+ virtual Status NewRandomAccessFile(const std::string& fname,
+ RandomAccessFile** result) {
+ int flags = ::base::PLATFORM_FILE_READ | ::base::PLATFORM_FILE_OPEN;
+ bool created;
+ ::base::PlatformFileError error_code;
+ ::base::PlatformFile file = ::base::CreatePlatformFile(
+ CreateFilePath(fname), flags, &created, &error_code);
+ if (error_code != ::base::PLATFORM_FILE_OK) {
+ *result = NULL;
+ return Status::IOError(fname, PlatformFileErrorString(error_code));
+ }
+ ::base::PlatformFileInfo info;
+ if (!::base::GetPlatformFileInfo(file, &info)) {
+ *result = NULL;
+ ::base::ClosePlatformFile(file);
+ return Status::IOError(fname, PlatformFileErrorString(error_code));
+ }
+ *result = new ChromiumRandomAccessFile(fname, info.size, file);
+ return Status::OK();
+ }
+
+ virtual Status NewWritableFile(const std::string& fname,
+ WritableFile** result) {
+ *result = NULL;
+ FILE* f = fopen(fname.c_str(), "wb");
+ if (f == NULL) {
+ return Status::IOError(fname, strerror(errno));
+ } else {
+ *result = new ChromiumWritableFile(fname, f);
+ return Status::OK();
+ }
+ }
+
+ virtual bool FileExists(const std::string& fname) {
+ return ::file_util::PathExists(CreateFilePath(fname));
+ }
+
+ virtual Status GetChildren(const std::string& dir,
+ std::vector<std::string>* result) {
+ result->clear();
+ ::file_util::FileEnumerator iter(
+ CreateFilePath(dir), false, ::file_util::FileEnumerator::FILES);
+ ::FilePath current = iter.Next();
+ while (!current.empty()) {
+ result->push_back(FilePathToString(current.BaseName()));
+ current = iter.Next();
+ }
+ // TODO(jorlow): Unfortunately, the FileEnumerator swallows errors, so
+ // we'll always return OK. Maybe manually check for error
+ // conditions like the file not existing?
+ return Status::OK();
+ }
+
+ virtual Status DeleteFile(const std::string& fname) {
+ Status result;
+ // TODO(jorlow): Should we assert this is a file?
+ if (!::file_util::Delete(CreateFilePath(fname), false)) {
+ result = Status::IOError(fname, "Could not delete file.");
+ }
+ return result;
+ };
+
+ virtual Status CreateDir(const std::string& name) {
+ Status result;
+ if (!::file_util::CreateDirectory(CreateFilePath(name))) {
+ result = Status::IOError(name, "Could not create directory.");
+ }
+ return result;
+ };
+
+ virtual Status DeleteDir(const std::string& name) {
+ Status result;
+ // TODO(jorlow): Should we assert this is a directory?
+ if (!::file_util::Delete(CreateFilePath(name), false)) {
+ result = Status::IOError(name, "Could not delete directory.");
+ }
+ return result;
+ };
+
+ virtual Status GetFileSize(const std::string& fname, uint64_t* size) {
+ Status s;
+ int64 signed_size;
+ if (!::file_util::GetFileSize(CreateFilePath(fname), &signed_size)) {
+ *size = 0;
+ s = Status::IOError(fname, "Could not determine file size.");
+ } else {
+ *size = static_cast<uint64_t>(signed_size);
+ }
+ return s;
+ }
+
+ virtual Status RenameFile(const std::string& src, const std::string& dst) {
+ Status result;
+ if (!::file_util::ReplaceFile(CreateFilePath(src), CreateFilePath(dst))) {
+ result = Status::IOError(src, "Could not rename file.");
+ }
+ return result;
+ }
+
+ virtual Status LockFile(const std::string& fname, FileLock** lock) {
+ *lock = NULL;
+ Status result;
+ int flags = ::base::PLATFORM_FILE_OPEN_ALWAYS |
+ ::base::PLATFORM_FILE_READ |
+ ::base::PLATFORM_FILE_WRITE |
+ ::base::PLATFORM_FILE_EXCLUSIVE_READ |
+ ::base::PLATFORM_FILE_EXCLUSIVE_WRITE;
+ bool created;
+ ::base::PlatformFileError error_code;
+ ::base::PlatformFile file = ::base::CreatePlatformFile(
+ CreateFilePath(fname), flags, &created, &error_code);
+ if (error_code != ::base::PLATFORM_FILE_OK) {
+ result = Status::IOError(fname, PlatformFileErrorString(error_code));
+ } else {
+ ChromiumFileLock* my_lock = new ChromiumFileLock;
+ my_lock->file_ = file;
+ *lock = my_lock;
+ }
+ return result;
+ }
+
+ virtual Status UnlockFile(FileLock* lock) {
+ ChromiumFileLock* my_lock = reinterpret_cast<ChromiumFileLock*>(lock);
+ Status result;
+ if (!::base::ClosePlatformFile(my_lock->file_)) {
+ result = Status::IOError("Could not close lock file.");
+ }
+ delete my_lock;
+ return result;
+ }
+
+ virtual void Schedule(void (*function)(void*), void* arg);
+
+ virtual void StartThread(void (*function)(void* arg), void* arg);
+
+ virtual std::string UserIdentifier() {
+#if defined(OS_WIN)
+ std::wstring user_sid;
+ bool ret = ::base::win::GetUserSidString(&user_sid);
+ DCHECK(ret);
+ return UTF16ToUTF8(user_sid);
+#else
+ char buf[100];
+ snprintf(buf, sizeof(buf), "%d", int(geteuid()));
+ return buf;
+#endif
+ }
+
+ virtual Status GetTestDirectory(std::string* path) {
+ if (test_directory_.empty()) {
+ if (!::file_util::CreateNewTempDirectory("leveldb-", &test_directory_)) {
+ return Status::IOError("Could not create temp directory.");
+ }
+ }
+ *path = FilePathToString(test_directory_);
+ return Status::OK();
+ }
+
+ virtual void Logv(WritableFile* info_log, const char* format, va_list ap) {
+ // TODO(jorlow): We may want to just use Chromium's built in logging.
+
+ uint64_t thread_id = 0;
+ // Coppied from base/logging.cc.
+#if defined(OS_WIN)
+ thread_id = GetCurrentThreadId();
+#elif defined(OS_MACOSX)
+ thread_id = mach_thread_self();
+#elif defined(OS_LINUX)
+ thread_id = syscall(__NR_gettid);
+#elif defined(OS_FREEBSD) || defined(OS_NACL)
+ // TODO(BSD): find a better thread ID
+ pthread_t tid = pthread_self();
+ memcpy(&thread_id, &tid, min(sizeof(r), sizeof(tid)));
+#endif
+
+ // We try twice: the first time with a fixed-size stack allocated buffer,
+ // and the second time with a much larger dynamically allocated buffer.
+ char buffer[500];
+ for (int iter = 0; iter < 2; iter++) {
+ char* base;
+ int bufsize;
+ if (iter == 0) {
+ bufsize = sizeof(buffer);
+ base = buffer;
+ } else {
+ bufsize = 30000;
+ base = new char[bufsize];
+ }
+ char* p = base;
+ char* limit = base + bufsize;
+
+ ::base::Time::Exploded t;
+ ::base::Time::Now().LocalExplode(&t);
+ p += snprintf(p, limit - p,
+ "%04d/%02d/%02d-%02d:%02d:%02d.%06d %llx ",
+ t.year,
+ t.month,
+ t.day_of_month,
+ t.hour,
+ t.minute,
+ t.second,
+ static_cast<int>(t.millisecond) * 1000,
+ static_cast<long long unsigned int>(thread_id));
+
+ // Print the message
+ if (p < limit) {
+ va_list backup_ap;
+ va_copy(backup_ap, ap);
+ p += vsnprintf(p, limit - p, format, backup_ap);
+ va_end(backup_ap);
+ }
+
+ // Truncate to available space if necessary
+ if (p >= limit) {
+ if (iter == 0) {
+ continue; // Try again with larger buffer
+ } else {
+ p = limit - 1;
+ }
+ }
+
+ // Add newline if necessary
+ if (p == base || p[-1] != '\n') {
+ *p++ = '\n';
+ }
+
+ assert(p <= limit);
+ info_log->Append(Slice(base, p - base));
+ info_log->Flush();
+ if (base != buffer) {
+ delete[] base;
+ }
+ break;
+ }
+ }
+
+ virtual int AppendLocalTimeToBuffer(char* buffer, size_t size) {
+ ::base::Time::Exploded t;
+ ::base::Time::Now().LocalExplode(&t);
+ return snprintf(buffer, size,
+ "%04d/%02d/%02d-%02d:%02d:%02d.%06d",
+ t.year,
+ t.month,
+ t.day_of_month,
+ t.hour,
+ t.minute,
+ t.second,
+ static_cast<int>(t.millisecond) * 1000);
+ }
+
+ virtual uint64_t NowMicros() {
+ return ::base::TimeTicks::HighResNow().ToInternalValue();
+ }
+
+ virtual void SleepForMicroseconds(int micros) {
+ // Round up to the next millisecond.
+ ::base::PlatformThread::Sleep((micros + 999) / 1000);
+ }
+
+ private:
+ // BGThread() is the body of the background thread
+ void BGThread();
+ static void BGThreadWrapper(void* arg) {
+ reinterpret_cast<ChromiumEnv*>(arg)->BGThread();
+ }
+
+ FilePath test_directory_;
+
+ size_t page_size_;
+ ::base::Lock mu_;
+ ::base::ConditionVariable bgsignal_;
+ bool started_bgthread_;
+
+ // Entry per Schedule() call
+ struct BGItem { void* arg; void (*function)(void*); };
+ typedef std::deque<BGItem> BGQueue;
+ BGQueue queue_;
+};
+
+ChromiumEnv::ChromiumEnv()
+ : page_size_(::base::SysInfo::VMAllocationGranularity()),
+ bgsignal_(&mu_),
+ started_bgthread_(false) {
+#if defined(OS_MACOSX)
+ ::base::EnableTerminationOnHeapCorruption();
+ ::base::EnableTerminationOnOutOfMemory();
+#endif // OS_MACOSX
+}
+
+class Thread : public ::base::PlatformThread::Delegate {
+ public:
+ Thread(void (*function)(void* arg), void* arg)
+ : function_(function), arg_(arg) {
+ ::base::PlatformThreadHandle handle;
+ bool success = ::base::PlatformThread::Create(0, this, &handle);
+ DCHECK(success);
+ }
+ virtual ~Thread() {}
+ virtual void ThreadMain() {
+ (*function_)(arg_);
+ delete this;
+ }
+
+ private:
+ void (*function_)(void* arg);
+ void* arg_;
+};
+
+void ChromiumEnv::Schedule(void (*function)(void*), void* arg) {
+ mu_.Acquire();
+
+ // Start background thread if necessary
+ if (!started_bgthread_) {
+ started_bgthread_ = true;
+ StartThread(&ChromiumEnv::BGThreadWrapper, this);
+ }
+
+ // If the queue is currently empty, the background thread may currently be
+ // waiting.
+ if (queue_.empty()) {
+ bgsignal_.Signal();
+ }
+
+ // Add to priority queue
+ queue_.push_back(BGItem());
+ queue_.back().function = function;
+ queue_.back().arg = arg;
+
+ mu_.Release();
+}
+
+void ChromiumEnv::BGThread() {
+ while (true) {
+ // Wait until there is an item that is ready to run
+ mu_.Acquire();
+ while (queue_.empty()) {
+ bgsignal_.Wait();
+ }
+
+ void (*function)(void*) = queue_.front().function;
+ void* arg = queue_.front().arg;
+ queue_.pop_front();
+
+ mu_.Release();
+ (*function)(arg);
+ }
+}
+
+void ChromiumEnv::StartThread(void (*function)(void* arg), void* arg) {
+ new Thread(function, arg); // Will self-delete.
+}
+
+// TODO(jorlow): This won't co-exist with Chrome. Need to find a better way.
+::base::AtExitManager exit_manager;
+
+::base::LazyInstance<ChromiumEnv> default_env(::base::LINKER_INITIALIZED);
+
+}
+
+Env* Env::Default() {
+ return default_env.Pointer();
+}
+
+}
diff --git a/util/env_posix.cc b/util/env_posix.cc
new file mode 100644
index 0000000..b662f9c
--- /dev/null
+++ b/util/env_posix.cc
@@ -0,0 +1,609 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include <deque>
+#include <dirent.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <pthread.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/mman.h>
+#include <sys/stat.h>
+#include <sys/time.h>
+#include <sys/types.h>
+#include <time.h>
+#include <unistd.h>
+#if defined(LEVELDB_PLATFORM_ANDROID)
+#include <sys/stat.h>
+#endif
+#include "include/env.h"
+#include "include/slice.h"
+#include "port/port.h"
+#include "util/logging.h"
+
+namespace leveldb {
+
+namespace {
+
+class PosixSequentialFile: public SequentialFile {
+ private:
+ std::string filename_;
+ FILE* file_;
+
+ public:
+ PosixSequentialFile(const std::string& fname, FILE* f)
+ : filename_(fname), file_(f) { }
+ virtual ~PosixSequentialFile() { fclose(file_); }
+
+ virtual Status Read(size_t n, Slice* result, char* scratch) {
+ Status s;
+ size_t r = fread_unlocked(scratch, 1, n, file_);
+ *result = Slice(scratch, r);
+ if (r < n) {
+ if (feof(file_)) {
+ // We leave status as ok if we hit the end of the file
+ } else {
+ // A partial read with an error: return a non-ok status
+ s = Status::IOError(filename_, strerror(errno));
+ }
+ }
+ return s;
+ }
+};
+
+class PosixRandomAccessFile: public RandomAccessFile {
+ private:
+ std::string filename_;
+ uint64_t size_;
+ int fd_;
+
+ public:
+ PosixRandomAccessFile(const std::string& fname, uint64_t size, int fd)
+ : filename_(fname), size_(size), fd_(fd) { }
+ virtual ~PosixRandomAccessFile() { close(fd_); }
+
+ virtual uint64_t Size() const { return size_; }
+
+ virtual Status Read(uint64_t offset, size_t n, Slice* result,
+ char* scratch) const {
+ Status s;
+ ssize_t r = pread(fd_, scratch, n, static_cast<off_t>(offset));
+ *result = Slice(scratch, (r < 0) ? 0 : r);
+ if (r < 0) {
+ // An error: return a non-ok status
+ s = Status::IOError(filename_, strerror(errno));
+ }
+ return s;
+ }
+};
+
+// We preallocate up to an extra megabyte and use memcpy to append new
+// data to the file. This is safe since we either properly close the
+// file before reading from it, or for log files, the reading code
+// knows enough to skip zero suffixes.
+class PosixMmapFile : public WritableFile {
+ private:
+ std::string filename_;
+ int fd_;
+ size_t page_size_;
+ size_t map_size_; // How much extra memory to map at a time
+ char* base_; // The mapped region
+ char* limit_; // Limit of the mapped region
+ char* dst_; // Where to write next (in range [base_,limit_])
+ char* last_sync_; // Where have we synced up to
+ uint64_t file_offset_; // Offset of base_ in file
+
+ // Have we done an munmap of unsynced data?
+ bool pending_sync_;
+
+ // Roundup x to a multiple of y
+ static size_t Roundup(size_t x, size_t y) {
+ return ((x + y - 1) / y) * y;
+ }
+
+ size_t TruncateToPageBoundary(size_t s) {
+ s -= (s & (page_size_ - 1));
+ assert((s % page_size_) == 0);
+ return s;
+ }
+
+ void UnmapCurrentRegion() {
+ if (base_ != NULL) {
+ if (last_sync_ < limit_) {
+ // Defer syncing this data until next Sync() call, if any
+ pending_sync_ = true;
+ }
+ munmap(base_, limit_ - base_);
+ file_offset_ += limit_ - base_;
+ base_ = NULL;
+ limit_ = NULL;
+ last_sync_ = NULL;
+ dst_ = NULL;
+
+ // Increase the amount we map the next time, but capped at 1MB
+ if (map_size_ < (1<<20)) {
+ map_size_ *= 2;
+ }
+ }
+ }
+
+ bool MapNewRegion() {
+ assert(base_ == NULL);
+ if (ftruncate(fd_, file_offset_ + map_size_) < 0) {
+ return false;
+ }
+ void* ptr = mmap(NULL, map_size_, PROT_READ | PROT_WRITE, MAP_SHARED,
+ fd_, file_offset_);
+ if (ptr == MAP_FAILED) {
+ return false;
+ }
+ base_ = reinterpret_cast<char*>(ptr);
+ limit_ = base_ + map_size_;
+ dst_ = base_;
+ last_sync_ = base_;
+ return true;
+ }
+
+ public:
+ PosixMmapFile(const std::string& fname, int fd, size_t page_size)
+ : filename_(fname),
+ fd_(fd),
+ page_size_(page_size),
+ map_size_(Roundup(65536, page_size)),
+ base_(NULL),
+ limit_(NULL),
+ dst_(NULL),
+ last_sync_(NULL),
+ file_offset_(0),
+ pending_sync_(false) {
+ assert((page_size & (page_size - 1)) == 0);
+ }
+
+
+ ~PosixMmapFile() {
+ if (fd_ >= 0) {
+ PosixMmapFile::Close();
+ }
+ }
+
+ virtual Status Append(const Slice& data) {
+ const char* src = data.data();
+ size_t left = data.size();
+ while (left > 0) {
+ assert(base_ <= dst_);
+ assert(dst_ <= limit_);
+ size_t avail = limit_ - dst_;
+ if (avail == 0) {
+ UnmapCurrentRegion();
+ MapNewRegion();
+ }
+
+ size_t n = (left <= avail) ? left : avail;
+ memcpy(dst_, src, n);
+ dst_ += n;
+ src += n;
+ left -= n;
+ }
+ return Status::OK();
+ }
+
+ virtual Status Close() {
+ Status s;
+ size_t unused = limit_ - dst_;
+ UnmapCurrentRegion();
+ if (unused > 0) {
+ // Trim the extra space at the end of the file
+ if (ftruncate(fd_, file_offset_ - unused) < 0) {
+ s = Status::IOError(filename_, strerror(errno));
+ }
+ }
+
+ if (close(fd_) < 0) {
+ if (s.ok()) {
+ s = Status::IOError(filename_, strerror(errno));
+ }
+ }
+
+ fd_ = -1;
+ base_ = NULL;
+ limit_ = NULL;
+ return s;
+ }
+
+ virtual Status Flush() {
+ return Status::OK();
+ }
+
+ virtual Status Sync() {
+ Status s;
+
+ if (pending_sync_) {
+ // Some unmapped data was not synced
+ pending_sync_ = false;
+ if (fdatasync(fd_) < 0) {
+ s = Status::IOError(filename_, strerror(errno));
+ }
+ }
+
+ if (dst_ > last_sync_) {
+ // Find the beginnings of the pages that contain the first and last
+ // bytes to be synced.
+ size_t p1 = TruncateToPageBoundary(last_sync_ - base_);
+ size_t p2 = TruncateToPageBoundary(dst_ - base_ - 1);
+ last_sync_ = dst_;
+ if (msync(base_ + p1, p2 - p1 + page_size_, MS_SYNC) < 0) {
+ s = Status::IOError(filename_, strerror(errno));
+ }
+ }
+
+ return s;
+ }
+};
+
+static int LockOrUnlock(int fd, bool lock) {
+ errno = 0;
+ struct flock f;
+ memset(&f, 0, sizeof(f));
+ f.l_type = (lock ? F_WRLCK : F_UNLCK);
+ f.l_whence = SEEK_SET;
+ f.l_start = 0;
+ f.l_len = 0; // Lock/unlock entire file
+ return fcntl(fd, F_SETLK, &f);
+}
+
+class PosixFileLock : public FileLock {
+ public:
+ int fd_;
+};
+
+class PosixEnv : public Env {
+ public:
+ PosixEnv();
+ virtual ~PosixEnv() {
+ fprintf(stderr, "Destroying Env::Default()\n");
+ exit(1);
+ }
+
+ virtual Status NewSequentialFile(const std::string& fname,
+ SequentialFile** result) {
+ FILE* f = fopen(fname.c_str(), "r");
+ if (f == NULL) {
+ *result = NULL;
+ return Status::IOError(fname, strerror(errno));
+ } else {
+ *result = new PosixSequentialFile(fname, f);
+ return Status::OK();
+ }
+ }
+
+ virtual Status NewRandomAccessFile(const std::string& fname,
+ RandomAccessFile** result) {
+ int fd = open(fname.c_str(), O_RDONLY);
+ if (fd < 0) {
+ *result = NULL;
+ return Status::IOError(fname, strerror(errno));
+ }
+ struct stat sbuf;
+ if (fstat(fd, &sbuf) != 0) {
+ *result = NULL;
+ Status s = Status::IOError(fname, strerror(errno));
+ close(fd);
+ return s;
+ }
+ *result = new PosixRandomAccessFile(fname, sbuf.st_size, fd);
+ return Status::OK();
+ }
+
+ virtual Status NewWritableFile(const std::string& fname,
+ WritableFile** result) {
+ Status s;
+ const int fd = open(fname.c_str(), O_CREAT | O_RDWR | O_TRUNC, 0644);
+ if (fd < 0) {
+ *result = NULL;
+ s = Status::IOError(fname, strerror(errno));
+ } else {
+ *result = new PosixMmapFile(fname, fd, page_size_);
+ }
+ return s;
+ }
+
+ virtual bool FileExists(const std::string& fname) {
+ return access(fname.c_str(), F_OK) == 0;
+ }
+
+ virtual Status GetChildren(const std::string& dir,
+ std::vector<std::string>* result) {
+ result->clear();
+ DIR* d = opendir(dir.c_str());
+ if (d == NULL) {
+ return Status::IOError(dir, strerror(errno));
+ }
+ struct dirent* entry;
+ while ((entry = readdir(d)) != NULL) {
+ result->push_back(entry->d_name);
+ }
+ closedir(d);
+ return Status::OK();
+ }
+
+ virtual Status DeleteFile(const std::string& fname) {
+ Status result;
+ if (unlink(fname.c_str()) != 0) {
+ result = Status::IOError(fname, strerror(errno));
+ }
+ return result;
+ };
+
+ virtual Status CreateDir(const std::string& name) {
+ Status result;
+ if (mkdir(name.c_str(), 0755) != 0) {
+ result = Status::IOError(name, strerror(errno));
+ }
+ return result;
+ };
+
+ virtual Status DeleteDir(const std::string& name) {
+ Status result;
+ if (rmdir(name.c_str()) != 0) {
+ result = Status::IOError(name, strerror(errno));
+ }
+ return result;
+ };
+
+ virtual Status GetFileSize(const std::string& fname, uint64_t* size) {
+ Status s;
+ struct stat sbuf;
+ if (stat(fname.c_str(), &sbuf) != 0) {
+ *size = 0;
+ s = Status::IOError(fname, strerror(errno));
+ } else {
+ *size = sbuf.st_size;
+ }
+ return s;
+ }
+
+ virtual Status RenameFile(const std::string& src, const std::string& target) {
+ Status result;
+ if (rename(src.c_str(), target.c_str()) != 0) {
+ result = Status::IOError(src, strerror(errno));
+ }
+ return result;
+ }
+
+ virtual Status LockFile(const std::string& fname, FileLock** lock) {
+ *lock = NULL;
+ Status result;
+ int fd = open(fname.c_str(), O_RDWR | O_CREAT, 0644);
+ if (fd < 0) {
+ result = Status::IOError(fname, strerror(errno));
+ } else if (LockOrUnlock(fd, true) == -1) {
+ result = Status::IOError("lock " + fname, strerror(errno));
+ close(fd);
+ } else {
+ PosixFileLock* my_lock = new PosixFileLock;
+ my_lock->fd_ = fd;
+ *lock = my_lock;
+ }
+ return result;
+ }
+
+ virtual Status UnlockFile(FileLock* lock) {
+ PosixFileLock* my_lock = reinterpret_cast<PosixFileLock*>(lock);
+ Status result;
+ if (LockOrUnlock(my_lock->fd_, false) == -1) {
+ result = Status::IOError(strerror(errno));
+ }
+ close(my_lock->fd_);
+ delete my_lock;
+ return result;
+ }
+
+ virtual void Schedule(void (*function)(void*), void* arg);
+
+ virtual void StartThread(void (*function)(void* arg), void* arg);
+
+ virtual Status GetTestDirectory(std::string* result) {
+ const char* env = getenv("TEST_TMPDIR");
+ if (env && env[0] != '\0') {
+ *result = env;
+ } else {
+ char buf[100];
+ snprintf(buf, sizeof(buf), "/tmp/leveldbtest-%d", int(geteuid()));
+ *result = buf;
+ }
+ // Directory may already exist
+ CreateDir(*result);
+ return Status::OK();
+ }
+
+ virtual void Logv(WritableFile* info_log, const char* format, va_list ap) {
+ pthread_t tid = pthread_self();
+ uint64_t thread_id = 0;
+ memcpy(&thread_id, &tid, min(sizeof(thread_id), sizeof(tid)));
+
+ // We try twice: the first time with a fixed-size stack allocated buffer,
+ // and the second time with a much larger dynamically allocated buffer.
+ char buffer[500];
+ for (int iter = 0; iter < 2; iter++) {
+ char* base;
+ int bufsize;
+ if (iter == 0) {
+ bufsize = sizeof(buffer);
+ base = buffer;
+ } else {
+ bufsize = 30000;
+ base = new char[bufsize];
+ }
+ char* p = base;
+ char* limit = base + bufsize;
+
+ struct timeval now_tv;
+ gettimeofday(&now_tv, NULL);
+ const time_t seconds = now_tv.tv_sec;
+ struct tm t;
+ localtime_r(&seconds, &t);
+ p += snprintf(p, limit - p,
+ "%04d/%02d/%02d-%02d:%02d:%02d.%06d %llx ",
+ t.tm_year + 1900,
+ t.tm_mon + 1,
+ t.tm_mday,
+ t.tm_hour,
+ t.tm_min,
+ t.tm_sec,
+ static_cast<int>(now_tv.tv_usec),
+ static_cast<long long unsigned int>(thread_id));
+
+ // Print the message
+ if (p < limit) {
+ va_list backup_ap;
+ va_copy(backup_ap, ap);
+ p += vsnprintf(p, limit - p, format, backup_ap);
+ va_end(backup_ap);
+ }
+
+ // Truncate to available space if necessary
+ if (p >= limit) {
+ if (iter == 0) {
+ continue; // Try again with larger buffer
+ } else {
+ p = limit - 1;
+ }
+ }
+
+ // Add newline if necessary
+ if (p == base || p[-1] != '\n') {
+ *p++ = '\n';
+ }
+
+ assert(p <= limit);
+ info_log->Append(Slice(base, p - base));
+ info_log->Flush();
+ if (base != buffer) {
+ delete[] base;
+ }
+ break;
+ }
+ }
+
+ virtual uint64_t NowMicros() {
+ struct timeval tv;
+ gettimeofday(&tv, NULL);
+ return static_cast<uint64_t>(tv.tv_sec) * 1000000 + tv.tv_usec;
+ }
+
+ virtual void SleepForMicroseconds(int micros) {
+ usleep(micros);
+ }
+
+ private:
+ void PthreadCall(const char* label, int result) {
+ if (result != 0) {
+ fprintf(stderr, "pthread %s: %s\n", label, strerror(result));
+ exit(1);
+ }
+ }
+
+ // BGThread() is the body of the background thread
+ void BGThread();
+ static void* BGThreadWrapper(void* arg) {
+ reinterpret_cast<PosixEnv*>(arg)->BGThread();
+ return NULL;
+ }
+
+ size_t page_size_;
+ pthread_mutex_t mu_;
+ pthread_cond_t bgsignal_;
+ pthread_t bgthread_;
+ bool started_bgthread_;
+
+ // Entry per Schedule() call
+ struct BGItem { void* arg; void (*function)(void*); };
+ typedef std::deque<BGItem> BGQueue;
+ BGQueue queue_;
+};
+
+PosixEnv::PosixEnv() : page_size_(getpagesize()),
+ started_bgthread_(false) {
+ PthreadCall("mutex_init", pthread_mutex_init(&mu_, NULL));
+ PthreadCall("cvar_init", pthread_cond_init(&bgsignal_, NULL));
+}
+
+void PosixEnv::Schedule(void (*function)(void*), void* arg) {
+ PthreadCall("lock", pthread_mutex_lock(&mu_));
+
+ // Start background thread if necessary
+ if (!started_bgthread_) {
+ started_bgthread_ = true;
+ PthreadCall(
+ "create thread",
+ pthread_create(&bgthread_, NULL, &PosixEnv::BGThreadWrapper, this));
+ }
+
+ // If the queue is currently empty, the background thread may currently be
+ // waiting.
+ if (queue_.empty()) {
+ PthreadCall("signal", pthread_cond_signal(&bgsignal_));
+ }
+
+ // Add to priority queue
+ queue_.push_back(BGItem());
+ queue_.back().function = function;
+ queue_.back().arg = arg;
+
+ PthreadCall("unlock", pthread_mutex_unlock(&mu_));
+}
+
+void PosixEnv::BGThread() {
+ while (true) {
+ // Wait until there is an item that is ready to run
+ PthreadCall("lock", pthread_mutex_lock(&mu_));
+ while (queue_.empty()) {
+ PthreadCall("wait", pthread_cond_wait(&bgsignal_, &mu_));
+ }
+
+ void (*function)(void*) = queue_.front().function;
+ void* arg = queue_.front().arg;
+ queue_.pop_front();
+
+ PthreadCall("unlock", pthread_mutex_unlock(&mu_));
+ (*function)(arg);
+ }
+}
+
+namespace {
+struct StartThreadState {
+ void (*user_function)(void*);
+ void* arg;
+};
+}
+static void* StartThreadWrapper(void* arg) {
+ StartThreadState* state = reinterpret_cast<StartThreadState*>(arg);
+ state->user_function(state->arg);
+ delete state;
+ return NULL;
+}
+
+void PosixEnv::StartThread(void (*function)(void* arg), void* arg) {
+ pthread_t t;
+ StartThreadState* state = new StartThreadState;
+ state->user_function = function;
+ state->arg = arg;
+ PthreadCall("start thread",
+ pthread_create(&t, NULL, &StartThreadWrapper, state));
+}
+
+}
+
+static pthread_once_t once = PTHREAD_ONCE_INIT;
+static Env* default_env;
+static void InitDefaultEnv() { default_env = new PosixEnv; }
+
+Env* Env::Default() {
+ pthread_once(&once, InitDefaultEnv);
+ return default_env;
+}
+
+}
diff --git a/util/env_test.cc b/util/env_test.cc
new file mode 100644
index 0000000..4d17564
--- /dev/null
+++ b/util/env_test.cc
@@ -0,0 +1,102 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "include/env.h"
+
+#include "port/port.h"
+#include "util/testharness.h"
+
+namespace leveldb {
+
+static const int kDelayMicros = 100000;
+
+class EnvPosixTest {
+ private:
+ port::Mutex mu_;
+ std::string events_;
+
+ public:
+ Env* env_;
+ EnvPosixTest() : env_(Env::Default()) { }
+};
+
+static void SetBool(void* ptr) {
+ *(reinterpret_cast<bool*>(ptr)) = true;
+}
+
+TEST(EnvPosixTest, RunImmediately) {
+ bool called = false;
+ env_->Schedule(&SetBool, &called);
+ Env::Default()->SleepForMicroseconds(kDelayMicros);
+ ASSERT_TRUE(called);
+}
+
+TEST(EnvPosixTest, RunMany) {
+ int last_id = 0;
+
+ struct CB {
+ int* last_id_ptr; // Pointer to shared slot
+ int id; // Order# for the execution of this callback
+
+ CB(int* p, int i) : last_id_ptr(p), id(i) { }
+
+ static void Run(void* v) {
+ CB* cb = reinterpret_cast<CB*>(v);
+ ASSERT_EQ(cb->id-1, *cb->last_id_ptr);
+ *cb->last_id_ptr = cb->id;
+ }
+ };
+
+ // Schedule in different order than start time
+ CB cb1(&last_id, 1);
+ CB cb2(&last_id, 2);
+ CB cb3(&last_id, 3);
+ CB cb4(&last_id, 4);
+ env_->Schedule(&CB::Run, &cb1);
+ env_->Schedule(&CB::Run, &cb2);
+ env_->Schedule(&CB::Run, &cb3);
+ env_->Schedule(&CB::Run, &cb4);
+
+ Env::Default()->SleepForMicroseconds(kDelayMicros);
+ ASSERT_EQ(4, last_id);
+}
+
+struct State {
+ port::Mutex mu;
+ int val;
+ int num_running;
+};
+
+static void ThreadBody(void* arg) {
+ State* s = reinterpret_cast<State*>(arg);
+ s->mu.Lock();
+ s->val += 1;
+ s->num_running -= 1;
+ s->mu.Unlock();
+}
+
+TEST(EnvPosixTest, StartThread) {
+ State state;
+ state.val = 0;
+ state.num_running = 3;
+ for (int i = 0; i < 3; i++) {
+ env_->StartThread(&ThreadBody, &state);
+ }
+ while (true) {
+ state.mu.Lock();
+ int num = state.num_running;
+ state.mu.Unlock();
+ if (num == 0) {
+ break;
+ }
+ Env::Default()->SleepForMicroseconds(kDelayMicros);
+ }
+ ASSERT_EQ(state.val, 3);
+}
+
+}
+
+int main(int argc, char** argv) {
+ return leveldb::test::RunAllTests();
+}
diff --git a/util/hash.cc b/util/hash.cc
new file mode 100644
index 0000000..d19afd1
--- /dev/null
+++ b/util/hash.cc
@@ -0,0 +1,45 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include <string.h>
+#include "util/coding.h"
+#include "util/hash.h"
+
+namespace leveldb {
+
+uint32_t Hash(const char* data, size_t n, uint32_t seed) {
+ // Similar to murmur hash
+ const uint32_t m = 0xc6a4a793;
+ const uint32_t r = 24;
+ const char* limit = data + n;
+ uint32_t h = seed ^ (n * m);
+
+ // Pick up four bytes at a time
+ while (data + 4 <= limit) {
+ uint32_t w = DecodeFixed32(data);
+ data += 4;
+ h += w;
+ h *= m;
+ h ^= (h >> 16);
+ }
+
+ // Pick up remaining bytes
+ switch (limit - data) {
+ case 3:
+ h += data[2] << 16;
+ // fall through
+ case 2:
+ h += data[1] << 8;
+ // fall through
+ case 1:
+ h += data[0];
+ h *= m;
+ h ^= (h >> r);
+ break;
+ }
+ return h;
+}
+
+
+}
diff --git a/util/hash.h b/util/hash.h
new file mode 100644
index 0000000..8889d56
--- /dev/null
+++ b/util/hash.h
@@ -0,0 +1,19 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+//
+// Simple hash function used for internal data structures
+
+#ifndef STORAGE_LEVELDB_UTIL_HASH_H_
+#define STORAGE_LEVELDB_UTIL_HASH_H_
+
+#include <stddef.h>
+#include <stdint.h>
+
+namespace leveldb {
+
+extern uint32_t Hash(const char* data, size_t n, uint32_t seed);
+
+}
+
+#endif // STORAGE_LEVELDB_UTIL_HASH_H_
diff --git a/util/histogram.cc b/util/histogram.cc
new file mode 100644
index 0000000..c5178ef
--- /dev/null
+++ b/util/histogram.cc
@@ -0,0 +1,128 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include <math.h>
+#include <stdio.h>
+#include "port/port.h"
+#include "util/histogram.h"
+
+namespace leveldb {
+
+const double Histogram::kBucketLimit[kNumBuckets] = {
+ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16, 18, 20, 25, 30, 35, 40, 45,
+ 50, 60, 70, 80, 90, 100, 120, 140, 160, 180, 200, 250, 300, 350, 400, 450,
+ 500, 600, 700, 800, 900, 1000, 1200, 1400, 1600, 1800, 2000, 2500, 3000,
+ 3500, 4000, 4500, 5000, 6000, 7000, 8000, 9000, 10000, 12000, 14000,
+ 16000, 18000, 20000, 25000, 30000, 35000, 40000, 45000, 50000, 60000,
+ 70000, 80000, 90000, 100000, 120000, 140000, 160000, 180000, 200000,
+ 250000, 300000, 350000, 400000, 450000, 500000, 600000, 700000, 800000,
+ 900000, 1000000, 1200000, 1400000, 1600000, 1800000, 2000000, 2500000,
+ 3000000, 3500000, 4000000, 4500000, 5000000, 6000000, 7000000, 8000000,
+ 9000000, 10000000, 12000000, 14000000, 16000000, 18000000, 20000000,
+ 25000000, 30000000, 35000000, 40000000, 45000000, 50000000, 60000000,
+ 70000000, 80000000, 90000000, 100000000, 120000000, 140000000, 160000000,
+ 180000000, 200000000, 250000000, 300000000, 350000000, 400000000,
+ 450000000, 500000000, 600000000, 700000000, 800000000, 900000000,
+ 1000000000, 1200000000, 1400000000, 1600000000, 1800000000, 2000000000,
+ 2500000000.0, 3000000000.0, 3500000000.0, 4000000000.0, 4500000000.0,
+ 5000000000.0, 6000000000.0, 7000000000.0, 8000000000.0, 9000000000.0,
+ 1e200,
+};
+
+void Histogram::Clear() {
+ min_ = kBucketLimit[kNumBuckets-1];
+ max_ = 0;
+ num_ = 0;
+ sum_ = 0;
+ sum_squares_ = 0;
+ for (int i = 0; i < kNumBuckets; i++) {
+ buckets_[i] = 0;
+ }
+}
+
+void Histogram::Add(double value) {
+ // Linear search is fast enough for our usage in db_bench
+ int b = 0;
+ while (b < kNumBuckets - 1 && kBucketLimit[b] <= value) {
+ b++;
+ }
+ buckets_[b] += 1.0;
+ if (min_ > value) min_ = value;
+ if (max_ < value) max_ = value;
+ num_++;
+ sum_ += value;
+ sum_squares_ += (value * value);
+}
+
+double Histogram::Median() const {
+ return Percentile(50.0);
+}
+
+double Histogram::Percentile(double p) const {
+ double threshold = num_ * (p / 100.0);
+ double sum = 0;
+ for (int b = 0; b < kNumBuckets; b++) {
+ sum += buckets_[b];
+ if (sum >= threshold) {
+ // Scale linearly within this bucket
+ double left_point = (b == 0) ? 0 : kBucketLimit[b-1];
+ double right_point = kBucketLimit[b];
+ double left_sum = sum - buckets_[b];
+ double right_sum = sum;
+ double pos = (threshold - left_sum) / (right_sum - left_sum);
+ double r = left_point + (right_point - left_point) * pos;
+ if (r < min_) r = min_;
+ if (r > max_) r = max_;
+ return r;
+ }
+ }
+ return max_;
+}
+
+double Histogram::Average() const {
+ if (num_ == 0.0) return 0;
+ return sum_ / num_;
+}
+
+double Histogram::StandardDeviation() const {
+ if (num_ == 0.0) return 0;
+ double variance = (sum_squares_ * num_ - sum_ * sum_) / (num_ * num_);
+ return sqrt(variance);
+}
+
+std::string Histogram::ToString() const {
+ std::string r;
+ char buf[200];
+ snprintf(buf, sizeof(buf),
+ "Count: %.0f Average: %.4f StdDev: %.2f\n",
+ num_, Average(), StandardDeviation());
+ r.append(buf);
+ snprintf(buf, sizeof(buf),
+ "Min: %.4f Median: %.4f Max: %.4f\n",
+ (num_ == 0.0 ? 0.0 : min_), Median(), max_);
+ r.append(buf);
+ r.append("------------------------------------------------------\n");
+ const double mult = 100.0 / num_;
+ double sum = 0;
+ for (int b = 0; b < kNumBuckets; b++) {
+ if (buckets_[b] <= 0.0) continue;
+ sum += buckets_[b];
+ snprintf(buf, sizeof(buf),
+ "[ %7.0f, %7.0f ) %7.0f %7.3f%% %7.3f%% ",
+ ((b == 0) ? 0.0 : kBucketLimit[b-1]), // left
+ kBucketLimit[b], // right
+ buckets_[b], // count
+ mult * buckets_[b], // percentage
+ mult * sum); // cumulative percentage
+ r.append(buf);
+
+ // Add hash marks based on percentage; 20 marks for 100%.
+ int marks = static_cast<int>(20*(buckets_[b] / num_) + 0.5);
+ r.append(marks, '#');
+ r.push_back('\n');
+ }
+ return r;
+}
+
+}
diff --git a/util/histogram.h b/util/histogram.h
new file mode 100644
index 0000000..f72f122
--- /dev/null
+++ b/util/histogram.h
@@ -0,0 +1,41 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#ifndef STORAGE_LEVELDB_UTIL_HISTOGRAM_H_
+#define STORAGE_LEVELDB_UTIL_HISTOGRAM_H_
+
+#include <string>
+
+namespace leveldb {
+
+class Histogram {
+ public:
+ Histogram() { }
+ ~Histogram() { }
+
+ void Clear();
+ void Add(double value);
+
+ std::string ToString() const;
+
+ private:
+ double min_;
+ double max_;
+ double num_;
+ double sum_;
+ double sum_squares_;
+
+ enum { kNumBuckets = 154 };
+ static const double kBucketLimit[kNumBuckets];
+ double buckets_[kNumBuckets];
+
+ double Median() const;
+ double Percentile(double p) const;
+ double Average() const;
+ double StandardDeviation() const;
+};
+
+}
+
+#endif // STORAGE_LEVELDB_UTIL_HISTOGRAM_H_
diff --git a/util/logging.cc b/util/logging.cc
new file mode 100644
index 0000000..6b7c410
--- /dev/null
+++ b/util/logging.cc
@@ -0,0 +1,81 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "util/logging.h"
+
+#include <errno.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include "include/env.h"
+#include "include/slice.h"
+
+namespace leveldb {
+
+void AppendNumberTo(std::string* str, uint64_t num) {
+ char buf[30];
+ snprintf(buf, sizeof(buf), "%llu", (unsigned long long) num);
+ str->append(buf);
+}
+
+void AppendEscapedStringTo(std::string* str, const Slice& value) {
+ for (int i = 0; i < value.size(); i++) {
+ char c = value[i];
+ if (c >= ' ' && c <= '~') {
+ str->push_back(c);
+ } else {
+ char buf[10];
+ snprintf(buf, sizeof(buf), "\\x%02x",
+ static_cast<unsigned int>(c) & 0xff);
+ str->append(buf);
+ }
+ }
+}
+
+std::string NumberToString(uint64_t num) {
+ std::string r;
+ AppendNumberTo(&r, num);
+ return r;
+}
+
+std::string EscapeString(const Slice& value) {
+ std::string r;
+ AppendEscapedStringTo(&r, value);
+ return r;
+}
+
+bool ConsumeChar(Slice* in, char c) {
+ if (!in->empty() && (*in)[0] == c) {
+ in->remove_prefix(1);
+ return true;
+ } else {
+ return false;
+ }
+}
+
+bool ConsumeDecimalNumber(Slice* in, uint64_t* val) {
+ uint64_t v = 0;
+ int digits = 0;
+ while (!in->empty()) {
+ char c = (*in)[0];
+ if (c >= '0' && c <= '9') {
+ ++digits;
+ const int delta = (c - '0');
+ static const uint64_t kMaxUint64 = ~static_cast<uint64_t>(0);
+ if (v > kMaxUint64/10 ||
+ (v == kMaxUint64/10 && delta > kMaxUint64%10)) {
+ // Overflow
+ return false;
+ }
+ v = (v * 10) + delta;
+ in->remove_prefix(1);
+ } else {
+ break;
+ }
+ }
+ *val = v;
+ return (digits > 0);
+}
+
+}
diff --git a/util/logging.h b/util/logging.h
new file mode 100644
index 0000000..1cd0a4b
--- /dev/null
+++ b/util/logging.h
@@ -0,0 +1,47 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+//
+// Must not be included from any .h files to avoid polluting the namespace
+// with macros.
+
+#ifndef STORAGE_LEVELDB_UTIL_LOGGING_H_
+#define STORAGE_LEVELDB_UTIL_LOGGING_H_
+
+#include <stdio.h>
+#include <stdint.h>
+#include <string>
+#include "port/port.h"
+
+namespace leveldb {
+
+class Slice;
+class WritableFile;
+
+// Append a human-readable printout of "num" to *str
+extern void AppendNumberTo(std::string* str, uint64_t num);
+
+// Append a human-readable printout of "value" to *str.
+// Escapes any non-printable characters found in "value".
+extern void AppendEscapedStringTo(std::string* str, const Slice& value);
+
+// Return a human-readable printout of "num"
+extern std::string NumberToString(uint64_t num);
+
+// Return a human-readable version of "value".
+// Escapes any non-printable characters found in "value".
+extern std::string EscapeString(const Slice& value);
+
+// If *in starts with "c", advances *in past the first character and
+// returns true. Otherwise, returns false.
+extern bool ConsumeChar(Slice* in, char c);
+
+// Parse a human-readable number from "*in" into *value. On success,
+// advances "*in" past the consumed number and sets "*val" to the
+// numeric value. Otherwise, returns false and leaves *in in an
+// unspecified state.
+extern bool ConsumeDecimalNumber(Slice* in, uint64_t* val);
+
+}
+
+#endif // STORAGE_LEVELDB_UTIL_LOGGING_H_
diff --git a/util/mutexlock.h b/util/mutexlock.h
new file mode 100644
index 0000000..05fe279
--- /dev/null
+++ b/util/mutexlock.h
@@ -0,0 +1,39 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#ifndef STORAGE_LEVELDB_UTIL_MUTEXLOCK_H_
+#define STORAGE_LEVELDB_UTIL_MUTEXLOCK_H_
+
+#include "port/port.h"
+
+namespace leveldb {
+
+// Helper class that locks a mutex on construction and unlocks the mutex when
+// the destructor of the MutexLock object is invoked.
+//
+// Typical usage:
+//
+// void MyClass::MyMethod() {
+// MutexLock l(&mu_); // mu_ is an instance variable
+// ... some complex code, possibly with multiple return paths ...
+// }
+
+class MutexLock {
+ public:
+ explicit MutexLock(port::Mutex *mu) : mu_(mu) {
+ this->mu_->Lock();
+ }
+ ~MutexLock() { this->mu_->Unlock(); }
+
+ private:
+ port::Mutex *const mu_;
+ // No copying allowed
+ MutexLock(const MutexLock&);
+ void operator=(const MutexLock&);
+};
+
+}
+
+
+#endif // STORAGE_LEVELDB_UTIL_MUTEXLOCK_H_
diff --git a/util/options.cc b/util/options.cc
new file mode 100644
index 0000000..b792bb1
--- /dev/null
+++ b/util/options.cc
@@ -0,0 +1,29 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "include/options.h"
+
+#include "include/comparator.h"
+#include "include/env.h"
+
+namespace leveldb {
+
+Options::Options()
+ : comparator(BytewiseComparator()),
+ create_if_missing(false),
+ error_if_exists(false),
+ paranoid_checks(false),
+ env(Env::Default()),
+ info_log(NULL),
+ write_buffer_size(1<<20),
+ max_open_files(1000),
+ large_value_threshold(65536),
+ block_cache(NULL),
+ block_size(8192),
+ block_restart_interval(16),
+ compression(kLightweightCompression) {
+}
+
+
+}
diff --git a/util/random.h b/util/random.h
new file mode 100644
index 0000000..2d458e8
--- /dev/null
+++ b/util/random.h
@@ -0,0 +1,59 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#ifndef STORAGE_LEVELDB_UTIL_RANDOM_H_
+#define STORAGE_LEVELDB_UTIL_RANDOM_H_
+
+#include <stdint.h>
+
+namespace leveldb {
+
+// A very simple random number generator. Not especially good at
+// generating truly random bits, but good enough for our needs in this
+// package.
+class Random {
+ private:
+ uint32_t seed_;
+ public:
+ explicit Random(uint32_t s) : seed_(s & 0x7fffffffu) { }
+ uint32_t Next() {
+ static const uint32_t M = 2147483647L; // 2^31-1
+ static const uint64_t A = 16807; // bits 14, 8, 7, 5, 2, 1, 0
+ // We are computing
+ // seed_ = (seed_ * A) % M, where M = 2^31-1
+ //
+ // seed_ must not be zero or M, or else all subsequent computed values
+ // will be zero or M respectively. For all other values, seed_ will end
+ // up cycling through every number in [1,M-1]
+ uint64_t product = seed_ * A;
+
+ // Compute (product % M) using the fact that ((x << 31) % M) == x.
+ seed_ = (product >> 31) + (product & M);
+ // The first reduction may overflow by 1 bit, so we may need to
+ // repeat. mod == M is not possible; using > allows the faster
+ // sign-bit-based test.
+ if (seed_ > M) {
+ seed_ -= M;
+ }
+ return seed_;
+ }
+ // Returns a uniformly distributed value in the range [0..n-1]
+ // REQUIRES: n > 0
+ uint32_t Uniform(int n) { return Next() % n; }
+
+ // Randomly returns true ~"1/n" of the time, and false otherwise.
+ // REQUIRES: n > 0
+ bool OneIn(int n) { return (Next() % n) == 0; }
+
+ // Skewed: pick "base" uniformly from range [0,max_log] and then
+ // return "base" random bits. The effect is to pick a number in the
+ // range [0,2^max_log-1] with exponential bias towards smaller numbers.
+ uint32_t Skewed(int max_log) {
+ return Uniform(1 << Uniform(max_log + 1));
+ }
+};
+
+}
+
+#endif // STORAGE_LEVELDB_UTIL_RANDOM_H_
diff --git a/util/status.cc b/util/status.cc
new file mode 100644
index 0000000..2ed799d
--- /dev/null
+++ b/util/status.cc
@@ -0,0 +1,59 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include <stdio.h>
+#include "port/port.h"
+#include "include/status.h"
+
+namespace leveldb {
+
+Status::Status(Code code, const Slice& msg, const Slice& msg2) {
+ assert(code != kOk);
+ state_ = new State(make_pair(code, std::string(msg.data(), msg.size())));
+ if (!msg2.empty()) {
+ state_->second.append(": ");
+ state_->second.append(msg2.data(), msg2.size());
+ }
+}
+
+std::string Status::ToString() const {
+ if (state_ == NULL) {
+ return "OK";
+ } else {
+ char tmp[30];
+ const char* type;
+ switch (state_->first) {
+ case kOk:
+ type = "OK";
+ break;
+ case kNotFound:
+ type = "NotFound";
+ break;
+ case kCorruption:
+ type = "Corruption: ";
+ break;
+ case kNotSupported:
+ type = "Not implemented: ";
+ break;
+ case kInvalidArgument:
+ type = "Invalid argument: ";
+ break;
+ case kIOError:
+ type = "IO error: ";
+ break;
+ default:
+ snprintf(tmp, sizeof(tmp), "Unknown code(%d): ",
+ static_cast<int>(state_->first));
+ type = tmp;
+ break;
+ }
+ std::string result(type);
+ if (!state_->second.empty()) {
+ result.append(state_->second);
+ }
+ return result;
+ }
+}
+
+}
diff --git a/util/testharness.cc b/util/testharness.cc
new file mode 100644
index 0000000..b686ac3
--- /dev/null
+++ b/util/testharness.cc
@@ -0,0 +1,65 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "util/testharness.h"
+
+#include <sys/stat.h>
+#include <sys/types.h>
+
+namespace leveldb {
+namespace test {
+
+namespace {
+struct Test {
+ const char* base;
+ const char* name;
+ void (*func)();
+};
+std::vector<Test>* tests;
+}
+
+bool RegisterTest(const char* base, const char* name, void (*func)()) {
+ if (tests == NULL) {
+ tests = new std::vector<Test>;
+ }
+ Test t;
+ t.base = base;
+ t.name = name;
+ t.func = func;
+ tests->push_back(t);
+ return true;
+}
+
+int RunAllTests() {
+ int num = 0;
+ if (tests != NULL) {
+ for (int i = 0; i < tests->size(); i++) {
+ const Test& t = (*tests)[i];
+ fprintf(stderr, "==== Test %s.%s\n", t.base, t.name);
+ (*t.func)();
+ ++num;
+ }
+ }
+ fprintf(stderr, "==== PASSED %d tests\n", num);
+ return 0;
+}
+
+std::string TmpDir() {
+ std::string dir;
+ Status s = Env::Default()->GetTestDirectory(&dir);
+ ASSERT_TRUE(s.ok()) << s.ToString();
+ return dir;
+}
+
+int RandomSeed() {
+ const char* env = getenv("TEST_RANDOM_SEED");
+ int result = (env != NULL ? atoi(env) : 301);
+ if (result <= 0) {
+ result = 301;
+ }
+ return result;
+}
+
+}
+}
diff --git a/util/testharness.h b/util/testharness.h
new file mode 100644
index 0000000..93309dc
--- /dev/null
+++ b/util/testharness.h
@@ -0,0 +1,129 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#ifndef STORAGE_LEVELDB_UTIL_TESTHARNESS_H_
+#define STORAGE_LEVELDB_UTIL_TESTHARNESS_H_
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <sstream>
+#include "include/env.h"
+#include "include/slice.h"
+#include "util/random.h"
+
+namespace leveldb {
+namespace test {
+
+// Run all tests registered by the TEST() macro.
+// Returns 0 if all tests pass.
+// Dies or returns a non-zero value if some test fails.
+extern int RunAllTests();
+
+// Return the directory to use for temporary storage.
+extern std::string TmpDir();
+
+// Return a randomization seed for this run. Typically returns the
+// same number on repeated invocations of this binary, but automated
+// runs may be able to vary the seed.
+extern int RandomSeed();
+
+// An instance of Tester is allocated to hold temporary state during
+// the execution of an assertion.
+class Tester {
+ private:
+ bool ok_;
+ const char* fname_;
+ int line_;
+ std::stringstream ss_;
+
+ public:
+ Tester(const char* f, int l)
+ : ok_(true), fname_(f), line_(l) {
+ }
+
+ ~Tester() {
+ if (!ok_) {
+ fprintf(stderr, "%s:%d:%s\n", fname_, line_, ss_.str().c_str());
+ exit(1);
+ }
+ }
+
+ Tester& Is(bool b, const char* msg) {
+ if (!b) {
+ ss_ << " Assertion failure " << msg;
+ ok_ = false;
+ }
+ return *this;
+ }
+
+ Tester& IsOk(const Status& s) {
+ if (!s.ok()) {
+ ss_ << " " << s.ToString();
+ ok_ = false;
+ }
+ return *this;
+ }
+
+#define BINARY_OP(name,op) \
+ template <class X, class Y> \
+ Tester& name(const X& x, const Y& y) { \
+ if (! (x op y)) { \
+ ss_ << " failed: " << x << (" " #op " ") << y; \
+ ok_ = false; \
+ } \
+ return *this; \
+ }
+
+ BINARY_OP(IsEq, ==)
+ BINARY_OP(IsNe, !=)
+ BINARY_OP(IsGe, >=)
+ BINARY_OP(IsGt, >)
+ BINARY_OP(IsLe, <=)
+ BINARY_OP(IsLt, <)
+#undef BINARY_OP
+
+ // Attach the specified value to the error message if an error has occurred
+ template <class V>
+ Tester& operator<<(const V& value) {
+ if (!ok_) {
+ ss_ << " " << value;
+ }
+ return *this;
+ }
+};
+
+#define ASSERT_TRUE(c) ::leveldb::test::Tester(__FILE__, __LINE__).Is((c), #c)
+#define ASSERT_OK(s) ::leveldb::test::Tester(__FILE__, __LINE__).IsOk((s))
+#define ASSERT_EQ(a,b) ::leveldb::test::Tester(__FILE__, __LINE__).IsEq((a),(b))
+#define ASSERT_NE(a,b) ::leveldb::test::Tester(__FILE__, __LINE__).IsNe((a),(b))
+#define ASSERT_GE(a,b) ::leveldb::test::Tester(__FILE__, __LINE__).IsGe((a),(b))
+#define ASSERT_GT(a,b) ::leveldb::test::Tester(__FILE__, __LINE__).IsGt((a),(b))
+#define ASSERT_LE(a,b) ::leveldb::test::Tester(__FILE__, __LINE__).IsLe((a),(b))
+#define ASSERT_LT(a,b) ::leveldb::test::Tester(__FILE__, __LINE__).IsLt((a),(b))
+
+#define TCONCAT(a,b) TCONCAT1(a,b)
+#define TCONCAT1(a,b) a##b
+
+#define TEST(base,name) \
+class TCONCAT(_Test_,name) : public base { \
+ public: \
+ void _Run(); \
+ static void _RunIt() { \
+ TCONCAT(_Test_,name) t; \
+ t._Run(); \
+ } \
+}; \
+bool TCONCAT(_Test_ignored_,name) = \
+ ::leveldb::test::RegisterTest(#base, #name, &TCONCAT(_Test_,name)::_RunIt); \
+void TCONCAT(_Test_,name)::_Run()
+
+// Register the specified test. Typically not used directly, but
+// invoked via the macro expansion of TEST.
+extern bool RegisterTest(const char* base, const char* name, void (*func)());
+
+
+}
+}
+
+#endif // STORAGE_LEVELDB_UTIL_TESTHARNESS_H_
diff --git a/util/testutil.cc b/util/testutil.cc
new file mode 100644
index 0000000..8d6cf3c
--- /dev/null
+++ b/util/testutil.cc
@@ -0,0 +1,51 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#include "util/testutil.h"
+
+#include "util/random.h"
+
+namespace leveldb {
+namespace test {
+
+Slice RandomString(Random* rnd, int len, std::string* dst) {
+ dst->resize(len);
+ for (int i = 0; i < len; i++) {
+ (*dst)[i] = static_cast<char>(' ' + rnd->Uniform(95)); // ' ' .. '~'
+ }
+ return Slice(*dst);
+}
+
+std::string RandomKey(Random* rnd, int len) {
+ // Make sure to generate a wide variety of characters so we
+ // test the boundary conditions for short-key optimizations.
+ static const char kTestChars[] = {
+ '\0', '\1', 'a', 'b', 'c', 'd', 'e', '\xfd', '\xfe', '\xff'
+ };
+ std::string result;
+ for (int i = 0; i < len; i++) {
+ result += kTestChars[rnd->Uniform(sizeof(kTestChars))];
+ }
+ return result;
+}
+
+
+extern Slice CompressibleString(Random* rnd, double compressed_fraction,
+ int len, std::string* dst) {
+ int raw = static_cast<int>(len * compressed_fraction);
+ if (raw < 1) raw = 1;
+ std::string raw_data;
+ RandomString(rnd, raw, &raw_data);
+
+ // Duplicate the random data until we have filled "len" bytes
+ dst->clear();
+ while (dst->size() < len) {
+ dst->append(raw_data);
+ }
+ dst->resize(len);
+ return Slice(*dst);
+}
+
+}
+}
diff --git a/util/testutil.h b/util/testutil.h
new file mode 100644
index 0000000..0e8a177
--- /dev/null
+++ b/util/testutil.h
@@ -0,0 +1,53 @@
+// Copyright (c) 2011 The LevelDB Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file. See the AUTHORS file for names of contributors.
+
+#ifndef STORAGE_LEVELDB_UTIL_TESTUTIL_H_
+#define STORAGE_LEVELDB_UTIL_TESTUTIL_H_
+
+#include "include/env.h"
+#include "include/slice.h"
+#include "util/random.h"
+
+namespace leveldb {
+namespace test {
+
+// Store in *dst a random string of length "len" and return a Slice that
+// references the generated data.
+extern Slice RandomString(Random* rnd, int len, std::string* dst);
+
+// Return a random key with the specified length that may contain interesting
+// characters (e.g. \x00, \xff, etc.).
+extern std::string RandomKey(Random* rnd, int len);
+
+// Store in *dst a string of length "len" that will compress to
+// "N*compressed_fraction" bytes and return a Slice that references
+// the generated data.
+extern Slice CompressibleString(Random* rnd, double compressed_fraction,
+ int len, std::string* dst);
+
+// A wrapper that allows injection of errors.
+class ErrorEnv : public EnvWrapper {
+ public:
+ bool writable_file_error_;
+ int num_writable_file_errors_;
+
+ ErrorEnv() : EnvWrapper(Env::Default()),
+ writable_file_error_(false),
+ num_writable_file_errors_(0) { }
+
+ virtual Status NewWritableFile(const std::string& fname,
+ WritableFile** result) {
+ if (writable_file_error_) {
+ ++num_writable_file_errors_;
+ *result = NULL;
+ return Status::IOError(fname, "fake error");
+ }
+ return target()->NewWritableFile(fname, result);
+ }
+};
+
+}
+}
+
+#endif // STORAGE_LEVELDB_UTIL_TESTUTIL_H_