1 // Copyright (c) 2011 The LevelDB Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file. See the AUTHORS file for names of contributors.
11 #include "leveldb/cache.h"
12 #include "leveldb/comparator.h"
13 #include "leveldb/db.h"
14 #include "leveldb/env.h"
15 #include "leveldb/filter_policy.h"
16 #include "leveldb/iterator.h"
17 #include "leveldb/options.h"
18 #include "leveldb/status.h"
19 #include "leveldb/write_batch.h"
22 using leveldb::Comparator;
23 using leveldb::CompressionType;
26 using leveldb::FileLock;
27 using leveldb::FilterPolicy;
28 using leveldb::Iterator;
29 using leveldb::kMajorVersion;
30 using leveldb::kMinorVersion;
31 using leveldb::Logger;
32 using leveldb::NewBloomFilterPolicy;
33 using leveldb::NewLRUCache;
34 using leveldb::Options;
35 using leveldb::RandomAccessFile;
37 using leveldb::ReadOptions;
38 using leveldb::SequentialFile;
40 using leveldb::Snapshot;
41 using leveldb::Status;
42 using leveldb::WritableFile;
43 using leveldb::WriteBatch;
44 using leveldb::WriteOptions;
48 struct leveldb_t { DB* rep; };
49 struct leveldb_iterator_t { Iterator* rep; };
50 struct leveldb_writebatch_t { WriteBatch rep; };
51 struct leveldb_snapshot_t { const Snapshot* rep; };
52 struct leveldb_readoptions_t { ReadOptions rep; };
53 struct leveldb_writeoptions_t { WriteOptions rep; };
54 struct leveldb_options_t { Options rep; };
55 struct leveldb_cache_t { Cache* rep; };
56 struct leveldb_seqfile_t { SequentialFile* rep; };
57 struct leveldb_randomfile_t { RandomAccessFile* rep; };
58 struct leveldb_writablefile_t { WritableFile* rep; };
59 struct leveldb_logger_t { Logger* rep; };
60 struct leveldb_filelock_t { FileLock* rep; };
62 struct leveldb_comparator_t : public Comparator {
64 void (*destructor_)(void*);
67 const char* a, size_t alen,
68 const char* b, size_t blen);
69 const char* (*name_)(void*);
71 virtual ~leveldb_comparator_t() {
72 (*destructor_)(state_);
75 virtual int Compare(const Slice& a, const Slice& b) const {
76 return (*compare_)(state_, a.data(), a.size(), b.data(), b.size());
79 virtual const char* Name() const {
80 return (*name_)(state_);
83 // No-ops since the C binding does not support key shortening methods.
84 virtual void FindShortestSeparator(std::string*, const Slice&) const { }
85 virtual void FindShortSuccessor(std::string* key) const { }
88 struct leveldb_filterpolicy_t : public FilterPolicy {
90 void (*destructor_)(void*);
91 const char* (*name_)(void*);
94 const char* const* key_array, const size_t* key_length_array,
96 size_t* filter_length);
97 unsigned char (*key_match_)(
99 const char* key, size_t length,
100 const char* filter, size_t filter_length);
102 virtual ~leveldb_filterpolicy_t() {
103 (*destructor_)(state_);
106 virtual const char* Name() const {
107 return (*name_)(state_);
110 virtual void CreateFilter(const Slice* keys, int n, std::string* dst) const {
111 std::vector<const char*> key_pointers(n);
112 std::vector<size_t> key_sizes(n);
113 for (int i = 0; i < n; i++) {
114 key_pointers[i] = keys[i].data();
115 key_sizes[i] = keys[i].size();
118 char* filter = (*create_)(state_, &key_pointers[0], &key_sizes[0], n, &len);
119 dst->append(filter, len);
123 virtual bool KeyMayMatch(const Slice& key, const Slice& filter) const {
124 return (*key_match_)(state_, key.data(), key.size(),
125 filter.data(), filter.size());
129 struct leveldb_env_t {
134 static bool SaveError(char** errptr, const Status& s) {
135 assert(errptr != NULL);
138 } else if (*errptr == NULL) {
139 *errptr = strdup(s.ToString().c_str());
141 // TODO(sanjay): Merge with existing error?
143 *errptr = strdup(s.ToString().c_str());
148 static char* CopyString(const std::string& str) {
149 char* result = reinterpret_cast<char*>(malloc(sizeof(char) * str.size()));
150 memcpy(result, str.data(), sizeof(char) * str.size());
154 leveldb_t* leveldb_open(
155 const leveldb_options_t* options,
159 if (SaveError(errptr, DB::Open(options->rep, std::string(name), &db))) {
162 leveldb_t* result = new leveldb_t;
167 void leveldb_close(leveldb_t* db) {
174 const leveldb_writeoptions_t* options,
175 const char* key, size_t keylen,
176 const char* val, size_t vallen,
179 db->rep->Put(options->rep, Slice(key, keylen), Slice(val, vallen)));
184 const leveldb_writeoptions_t* options,
185 const char* key, size_t keylen,
187 SaveError(errptr, db->rep->Delete(options->rep, Slice(key, keylen)));
193 const leveldb_writeoptions_t* options,
194 leveldb_writebatch_t* batch,
196 SaveError(errptr, db->rep->Write(options->rep, &batch->rep));
201 const leveldb_readoptions_t* options,
202 const char* key, size_t keylen,
207 Status s = db->rep->Get(options->rep, Slice(key, keylen), &tmp);
209 *vallen = tmp.size();
210 result = CopyString(tmp);
213 if (!s.IsNotFound()) {
214 SaveError(errptr, s);
220 leveldb_iterator_t* leveldb_create_iterator(
222 const leveldb_readoptions_t* options) {
223 leveldb_iterator_t* result = new leveldb_iterator_t;
224 result->rep = db->rep->NewIterator(options->rep);
228 const leveldb_snapshot_t* leveldb_create_snapshot(
230 leveldb_snapshot_t* result = new leveldb_snapshot_t;
231 result->rep = db->rep->GetSnapshot();
235 void leveldb_release_snapshot(
237 const leveldb_snapshot_t* snapshot) {
238 db->rep->ReleaseSnapshot(snapshot->rep);
242 char* leveldb_property_value(
244 const char* propname) {
246 if (db->rep->GetProperty(Slice(propname), &tmp)) {
247 // We use strdup() since we expect human readable output.
248 return strdup(tmp.c_str());
254 void leveldb_approximate_sizes(
257 const char* const* range_start_key, const size_t* range_start_key_len,
258 const char* const* range_limit_key, const size_t* range_limit_key_len,
260 Range* ranges = new Range[num_ranges];
261 for (int i = 0; i < num_ranges; i++) {
262 ranges[i].start = Slice(range_start_key[i], range_start_key_len[i]);
263 ranges[i].limit = Slice(range_limit_key[i], range_limit_key_len[i]);
265 db->rep->GetApproximateSizes(ranges, num_ranges, sizes);
269 void leveldb_compact_range(
271 const char* start_key, size_t start_key_len,
272 const char* limit_key, size_t limit_key_len) {
274 db->rep->CompactRange(
275 // Pass NULL Slice if corresponding "const char*" is NULL
276 (start_key ? (a = Slice(start_key, start_key_len), &a) : NULL),
277 (limit_key ? (b = Slice(limit_key, limit_key_len), &b) : NULL));
280 void leveldb_destroy_db(
281 const leveldb_options_t* options,
284 SaveError(errptr, DestroyDB(name, options->rep));
287 void leveldb_repair_db(
288 const leveldb_options_t* options,
291 SaveError(errptr, RepairDB(name, options->rep));
294 void leveldb_iter_destroy(leveldb_iterator_t* iter) {
299 unsigned char leveldb_iter_valid(const leveldb_iterator_t* iter) {
300 return iter->rep->Valid();
303 void leveldb_iter_seek_to_first(leveldb_iterator_t* iter) {
304 iter->rep->SeekToFirst();
307 void leveldb_iter_seek_to_last(leveldb_iterator_t* iter) {
308 iter->rep->SeekToLast();
311 void leveldb_iter_seek(leveldb_iterator_t* iter, const char* k, size_t klen) {
312 iter->rep->Seek(Slice(k, klen));
315 void leveldb_iter_next(leveldb_iterator_t* iter) {
319 void leveldb_iter_prev(leveldb_iterator_t* iter) {
323 const char* leveldb_iter_key(const leveldb_iterator_t* iter, size_t* klen) {
324 Slice s = iter->rep->key();
329 const char* leveldb_iter_value(const leveldb_iterator_t* iter, size_t* vlen) {
330 Slice s = iter->rep->value();
335 void leveldb_iter_get_error(const leveldb_iterator_t* iter, char** errptr) {
336 SaveError(errptr, iter->rep->status());
339 leveldb_writebatch_t* leveldb_writebatch_create() {
340 return new leveldb_writebatch_t;
343 void leveldb_writebatch_destroy(leveldb_writebatch_t* b) {
347 void leveldb_writebatch_clear(leveldb_writebatch_t* b) {
351 void leveldb_writebatch_put(
352 leveldb_writebatch_t* b,
353 const char* key, size_t klen,
354 const char* val, size_t vlen) {
355 b->rep.Put(Slice(key, klen), Slice(val, vlen));
358 void leveldb_writebatch_delete(
359 leveldb_writebatch_t* b,
360 const char* key, size_t klen) {
361 b->rep.Delete(Slice(key, klen));
364 void leveldb_writebatch_iterate(
365 leveldb_writebatch_t* b,
367 void (*put)(void*, const char* k, size_t klen, const char* v, size_t vlen),
368 void (*deleted)(void*, const char* k, size_t klen)) {
369 class H : public WriteBatch::Handler {
372 void (*put_)(void*, const char* k, size_t klen, const char* v, size_t vlen);
373 void (*deleted_)(void*, const char* k, size_t klen);
374 virtual void Put(const Slice& key, const Slice& value) {
375 (*put_)(state_, key.data(), key.size(), value.data(), value.size());
377 virtual void Delete(const Slice& key) {
378 (*deleted_)(state_, key.data(), key.size());
382 handler.state_ = state;
384 handler.deleted_ = deleted;
385 b->rep.Iterate(&handler);
388 leveldb_options_t* leveldb_options_create() {
389 return new leveldb_options_t;
392 void leveldb_options_destroy(leveldb_options_t* options) {
396 void leveldb_options_set_comparator(
397 leveldb_options_t* opt,
398 leveldb_comparator_t* cmp) {
399 opt->rep.comparator = cmp;
402 void leveldb_options_set_filter_policy(
403 leveldb_options_t* opt,
404 leveldb_filterpolicy_t* policy) {
405 opt->rep.filter_policy = policy;
408 void leveldb_options_set_create_if_missing(
409 leveldb_options_t* opt, unsigned char v) {
410 opt->rep.create_if_missing = v;
413 void leveldb_options_set_error_if_exists(
414 leveldb_options_t* opt, unsigned char v) {
415 opt->rep.error_if_exists = v;
418 void leveldb_options_set_paranoid_checks(
419 leveldb_options_t* opt, unsigned char v) {
420 opt->rep.paranoid_checks = v;
423 void leveldb_options_set_env(leveldb_options_t* opt, leveldb_env_t* env) {
424 opt->rep.env = (env ? env->rep : NULL);
427 void leveldb_options_set_info_log(leveldb_options_t* opt, leveldb_logger_t* l) {
428 opt->rep.info_log = (l ? l->rep : NULL);
431 void leveldb_options_set_write_buffer_size(leveldb_options_t* opt, size_t s) {
432 opt->rep.write_buffer_size = s;
435 void leveldb_options_set_max_open_files(leveldb_options_t* opt, int n) {
436 opt->rep.max_open_files = n;
439 void leveldb_options_set_cache(leveldb_options_t* opt, leveldb_cache_t* c) {
440 opt->rep.block_cache = c->rep;
443 void leveldb_options_set_block_size(leveldb_options_t* opt, size_t s) {
444 opt->rep.block_size = s;
447 void leveldb_options_set_block_restart_interval(leveldb_options_t* opt, int n) {
448 opt->rep.block_restart_interval = n;
451 void leveldb_options_set_compression(leveldb_options_t* opt, int t) {
452 opt->rep.compression = static_cast<CompressionType>(t);
455 leveldb_comparator_t* leveldb_comparator_create(
457 void (*destructor)(void*),
460 const char* a, size_t alen,
461 const char* b, size_t blen),
462 const char* (*name)(void*)) {
463 leveldb_comparator_t* result = new leveldb_comparator_t;
464 result->state_ = state;
465 result->destructor_ = destructor;
466 result->compare_ = compare;
467 result->name_ = name;
471 void leveldb_comparator_destroy(leveldb_comparator_t* cmp) {
475 leveldb_filterpolicy_t* leveldb_filterpolicy_create(
477 void (*destructor)(void*),
478 char* (*create_filter)(
480 const char* const* key_array, const size_t* key_length_array,
482 size_t* filter_length),
483 unsigned char (*key_may_match)(
485 const char* key, size_t length,
486 const char* filter, size_t filter_length),
487 const char* (*name)(void*)) {
488 leveldb_filterpolicy_t* result = new leveldb_filterpolicy_t;
489 result->state_ = state;
490 result->destructor_ = destructor;
491 result->create_ = create_filter;
492 result->key_match_ = key_may_match;
493 result->name_ = name;
497 void leveldb_filterpolicy_destroy(leveldb_filterpolicy_t* filter) {
501 leveldb_filterpolicy_t* leveldb_filterpolicy_create_bloom(int bits_per_key) {
502 // Make a leveldb_filterpolicy_t, but override all of its methods so
503 // they delegate to a NewBloomFilterPolicy() instead of user
504 // supplied C functions.
505 struct Wrapper : public leveldb_filterpolicy_t {
506 const FilterPolicy* rep_;
507 ~Wrapper() { delete rep_; }
508 const char* Name() const { return rep_->Name(); }
509 void CreateFilter(const Slice* keys, int n, std::string* dst) const {
510 return rep_->CreateFilter(keys, n, dst);
512 bool KeyMayMatch(const Slice& key, const Slice& filter) const {
513 return rep_->KeyMayMatch(key, filter);
515 static void DoNothing(void*) { }
517 Wrapper* wrapper = new Wrapper;
518 wrapper->rep_ = NewBloomFilterPolicy(bits_per_key);
519 wrapper->state_ = NULL;
520 wrapper->destructor_ = &Wrapper::DoNothing;
524 leveldb_readoptions_t* leveldb_readoptions_create() {
525 return new leveldb_readoptions_t;
528 void leveldb_readoptions_destroy(leveldb_readoptions_t* opt) {
532 void leveldb_readoptions_set_verify_checksums(
533 leveldb_readoptions_t* opt,
535 opt->rep.verify_checksums = v;
538 void leveldb_readoptions_set_fill_cache(
539 leveldb_readoptions_t* opt, unsigned char v) {
540 opt->rep.fill_cache = v;
543 void leveldb_readoptions_set_snapshot(
544 leveldb_readoptions_t* opt,
545 const leveldb_snapshot_t* snap) {
546 opt->rep.snapshot = (snap ? snap->rep : NULL);
549 leveldb_writeoptions_t* leveldb_writeoptions_create() {
550 return new leveldb_writeoptions_t;
553 void leveldb_writeoptions_destroy(leveldb_writeoptions_t* opt) {
557 void leveldb_writeoptions_set_sync(
558 leveldb_writeoptions_t* opt, unsigned char v) {
562 leveldb_cache_t* leveldb_cache_create_lru(size_t capacity) {
563 leveldb_cache_t* c = new leveldb_cache_t;
564 c->rep = NewLRUCache(capacity);
568 void leveldb_cache_destroy(leveldb_cache_t* cache) {
573 leveldb_env_t* leveldb_create_default_env() {
574 leveldb_env_t* result = new leveldb_env_t;
575 result->rep = Env::Default();
576 result->is_default = true;
580 void leveldb_env_destroy(leveldb_env_t* env) {
581 if (!env->is_default) delete env->rep;
585 void leveldb_free(void* ptr) {
589 int leveldb_major_version() {
590 return kMajorVersion;
593 int leveldb_minor_version() {
594 return kMinorVersion;