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.
9 #include "leveldb/cache.h"
10 #include "leveldb/comparator.h"
11 #include "leveldb/db.h"
12 #include "leveldb/env.h"
13 #include "leveldb/filter_policy.h"
14 #include "leveldb/iterator.h"
15 #include "leveldb/options.h"
16 #include "leveldb/status.h"
17 #include "leveldb/write_batch.h"
20 using leveldb::Comparator;
21 using leveldb::CompressionType;
24 using leveldb::FileLock;
25 using leveldb::FilterPolicy;
26 using leveldb::Iterator;
27 using leveldb::kMajorVersion;
28 using leveldb::kMinorVersion;
29 using leveldb::Logger;
30 using leveldb::NewBloomFilterPolicy;
31 using leveldb::NewLRUCache;
32 using leveldb::Options;
33 using leveldb::RandomAccessFile;
35 using leveldb::ReadOptions;
36 using leveldb::SequentialFile;
38 using leveldb::Snapshot;
39 using leveldb::Status;
40 using leveldb::WritableFile;
41 using leveldb::WriteBatch;
42 using leveldb::WriteOptions;
46 struct leveldb_t { DB* rep; };
47 struct leveldb_iterator_t { Iterator* rep; };
48 struct leveldb_writebatch_t { WriteBatch rep; };
49 struct leveldb_snapshot_t { const Snapshot* rep; };
50 struct leveldb_readoptions_t { ReadOptions rep; };
51 struct leveldb_writeoptions_t { WriteOptions rep; };
52 struct leveldb_options_t { Options rep; };
53 struct leveldb_cache_t { Cache* rep; };
54 struct leveldb_seqfile_t { SequentialFile* rep; };
55 struct leveldb_randomfile_t { RandomAccessFile* rep; };
56 struct leveldb_writablefile_t { WritableFile* rep; };
57 struct leveldb_logger_t { Logger* rep; };
58 struct leveldb_filelock_t { FileLock* rep; };
60 struct leveldb_comparator_t : public Comparator {
62 void (*destructor_)(void*);
65 const char* a, size_t alen,
66 const char* b, size_t blen);
67 const char* (*name_)(void*);
69 virtual ~leveldb_comparator_t() {
70 (*destructor_)(state_);
73 virtual int Compare(const Slice& a, const Slice& b) const {
74 return (*compare_)(state_, a.data(), a.size(), b.data(), b.size());
77 virtual const char* Name() const {
78 return (*name_)(state_);
81 // No-ops since the C binding does not support key shortening methods.
82 virtual void FindShortestSeparator(std::string*, const Slice&) const { }
83 virtual void FindShortSuccessor(std::string* key) const { }
86 struct leveldb_filterpolicy_t : public FilterPolicy {
88 void (*destructor_)(void*);
89 const char* (*name_)(void*);
92 const char* const* key_array, const size_t* key_length_array,
94 size_t* filter_length);
95 unsigned char (*key_match_)(
97 const char* key, size_t length,
98 const char* filter, size_t filter_length);
100 virtual ~leveldb_filterpolicy_t() {
101 (*destructor_)(state_);
104 virtual const char* Name() const {
105 return (*name_)(state_);
108 virtual void CreateFilter(const Slice* keys, int n, std::string* dst) const {
109 std::vector<const char*> key_pointers(n);
110 std::vector<size_t> key_sizes(n);
111 for (int i = 0; i < n; i++) {
112 key_pointers[i] = keys[i].data();
113 key_sizes[i] = keys[i].size();
116 char* filter = (*create_)(state_, &key_pointers[0], &key_sizes[0], n, &len);
117 dst->append(filter, len);
121 virtual bool KeyMayMatch(const Slice& key, const Slice& filter) const {
122 return (*key_match_)(state_, key.data(), key.size(),
123 filter.data(), filter.size());
127 struct leveldb_env_t {
132 static bool SaveError(char** errptr, const Status& s) {
133 assert(errptr != NULL);
136 } else if (*errptr == NULL) {
137 *errptr = strdup(s.ToString().c_str());
139 // TODO(sanjay): Merge with existing error?
141 *errptr = strdup(s.ToString().c_str());
146 static char* CopyString(const std::string& str) {
147 char* result = reinterpret_cast<char*>(malloc(sizeof(char) * str.size()));
148 memcpy(result, str.data(), sizeof(char) * str.size());
152 leveldb_t* leveldb_open(
153 const leveldb_options_t* options,
157 if (SaveError(errptr, DB::Open(options->rep, std::string(name), &db))) {
160 leveldb_t* result = new leveldb_t;
165 void leveldb_close(leveldb_t* db) {
172 const leveldb_writeoptions_t* options,
173 const char* key, size_t keylen,
174 const char* val, size_t vallen,
177 db->rep->Put(options->rep, Slice(key, keylen), Slice(val, vallen)));
182 const leveldb_writeoptions_t* options,
183 const char* key, size_t keylen,
185 SaveError(errptr, db->rep->Delete(options->rep, Slice(key, keylen)));
191 const leveldb_writeoptions_t* options,
192 leveldb_writebatch_t* batch,
194 SaveError(errptr, db->rep->Write(options->rep, &batch->rep));
199 const leveldb_readoptions_t* options,
200 const char* key, size_t keylen,
205 Status s = db->rep->Get(options->rep, Slice(key, keylen), &tmp);
207 *vallen = tmp.size();
208 result = CopyString(tmp);
211 if (!s.IsNotFound()) {
212 SaveError(errptr, s);
218 leveldb_iterator_t* leveldb_create_iterator(
220 const leveldb_readoptions_t* options) {
221 leveldb_iterator_t* result = new leveldb_iterator_t;
222 result->rep = db->rep->NewIterator(options->rep);
226 const leveldb_snapshot_t* leveldb_create_snapshot(
228 leveldb_snapshot_t* result = new leveldb_snapshot_t;
229 result->rep = db->rep->GetSnapshot();
233 void leveldb_release_snapshot(
235 const leveldb_snapshot_t* snapshot) {
236 db->rep->ReleaseSnapshot(snapshot->rep);
240 char* leveldb_property_value(
242 const char* propname) {
244 if (db->rep->GetProperty(Slice(propname), &tmp)) {
245 // We use strdup() since we expect human readable output.
246 return strdup(tmp.c_str());
252 void leveldb_approximate_sizes(
255 const char* const* range_start_key, const size_t* range_start_key_len,
256 const char* const* range_limit_key, const size_t* range_limit_key_len,
258 Range* ranges = new Range[num_ranges];
259 for (int i = 0; i < num_ranges; i++) {
260 ranges[i].start = Slice(range_start_key[i], range_start_key_len[i]);
261 ranges[i].limit = Slice(range_limit_key[i], range_limit_key_len[i]);
263 db->rep->GetApproximateSizes(ranges, num_ranges, sizes);
267 void leveldb_compact_range(
269 const char* start_key, size_t start_key_len,
270 const char* limit_key, size_t limit_key_len) {
272 db->rep->CompactRange(
273 // Pass NULL Slice if corresponding "const char*" is NULL
274 (start_key ? (a = Slice(start_key, start_key_len), &a) : NULL),
275 (limit_key ? (b = Slice(limit_key, limit_key_len), &b) : NULL));
278 void leveldb_destroy_db(
279 const leveldb_options_t* options,
282 SaveError(errptr, DestroyDB(name, options->rep));
285 void leveldb_repair_db(
286 const leveldb_options_t* options,
289 SaveError(errptr, RepairDB(name, options->rep));
292 void leveldb_iter_destroy(leveldb_iterator_t* iter) {
297 unsigned char leveldb_iter_valid(const leveldb_iterator_t* iter) {
298 return iter->rep->Valid();
301 void leveldb_iter_seek_to_first(leveldb_iterator_t* iter) {
302 iter->rep->SeekToFirst();
305 void leveldb_iter_seek_to_last(leveldb_iterator_t* iter) {
306 iter->rep->SeekToLast();
309 void leveldb_iter_seek(leveldb_iterator_t* iter, const char* k, size_t klen) {
310 iter->rep->Seek(Slice(k, klen));
313 void leveldb_iter_next(leveldb_iterator_t* iter) {
317 void leveldb_iter_prev(leveldb_iterator_t* iter) {
321 const char* leveldb_iter_key(const leveldb_iterator_t* iter, size_t* klen) {
322 Slice s = iter->rep->key();
327 const char* leveldb_iter_value(const leveldb_iterator_t* iter, size_t* vlen) {
328 Slice s = iter->rep->value();
333 void leveldb_iter_get_error(const leveldb_iterator_t* iter, char** errptr) {
334 SaveError(errptr, iter->rep->status());
337 leveldb_writebatch_t* leveldb_writebatch_create() {
338 return new leveldb_writebatch_t;
341 void leveldb_writebatch_destroy(leveldb_writebatch_t* b) {
345 void leveldb_writebatch_clear(leveldb_writebatch_t* b) {
349 void leveldb_writebatch_put(
350 leveldb_writebatch_t* b,
351 const char* key, size_t klen,
352 const char* val, size_t vlen) {
353 b->rep.Put(Slice(key, klen), Slice(val, vlen));
356 void leveldb_writebatch_delete(
357 leveldb_writebatch_t* b,
358 const char* key, size_t klen) {
359 b->rep.Delete(Slice(key, klen));
362 void leveldb_writebatch_iterate(
363 leveldb_writebatch_t* b,
365 void (*put)(void*, const char* k, size_t klen, const char* v, size_t vlen),
366 void (*deleted)(void*, const char* k, size_t klen)) {
367 class H : public WriteBatch::Handler {
370 void (*put_)(void*, const char* k, size_t klen, const char* v, size_t vlen);
371 void (*deleted_)(void*, const char* k, size_t klen);
372 virtual void Put(const Slice& key, const Slice& value) {
373 (*put_)(state_, key.data(), key.size(), value.data(), value.size());
375 virtual void Delete(const Slice& key) {
376 (*deleted_)(state_, key.data(), key.size());
380 handler.state_ = state;
382 handler.deleted_ = deleted;
383 b->rep.Iterate(&handler);
386 leveldb_options_t* leveldb_options_create() {
387 return new leveldb_options_t;
390 void leveldb_options_destroy(leveldb_options_t* options) {
394 void leveldb_options_set_comparator(
395 leveldb_options_t* opt,
396 leveldb_comparator_t* cmp) {
397 opt->rep.comparator = cmp;
400 void leveldb_options_set_filter_policy(
401 leveldb_options_t* opt,
402 leveldb_filterpolicy_t* policy) {
403 opt->rep.filter_policy = policy;
406 void leveldb_options_set_create_if_missing(
407 leveldb_options_t* opt, unsigned char v) {
408 opt->rep.create_if_missing = v;
411 void leveldb_options_set_error_if_exists(
412 leveldb_options_t* opt, unsigned char v) {
413 opt->rep.error_if_exists = v;
416 void leveldb_options_set_paranoid_checks(
417 leveldb_options_t* opt, unsigned char v) {
418 opt->rep.paranoid_checks = v;
421 void leveldb_options_set_env(leveldb_options_t* opt, leveldb_env_t* env) {
422 opt->rep.env = (env ? env->rep : NULL);
425 void leveldb_options_set_info_log(leveldb_options_t* opt, leveldb_logger_t* l) {
426 opt->rep.info_log = (l ? l->rep : NULL);
429 void leveldb_options_set_write_buffer_size(leveldb_options_t* opt, size_t s) {
430 opt->rep.write_buffer_size = s;
433 void leveldb_options_set_max_open_files(leveldb_options_t* opt, int n) {
434 opt->rep.max_open_files = n;
437 void leveldb_options_set_cache(leveldb_options_t* opt, leveldb_cache_t* c) {
438 opt->rep.block_cache = c->rep;
441 void leveldb_options_set_block_size(leveldb_options_t* opt, size_t s) {
442 opt->rep.block_size = s;
445 void leveldb_options_set_block_restart_interval(leveldb_options_t* opt, int n) {
446 opt->rep.block_restart_interval = n;
449 void leveldb_options_set_compression(leveldb_options_t* opt, int t) {
450 opt->rep.compression = static_cast<CompressionType>(t);
453 leveldb_comparator_t* leveldb_comparator_create(
455 void (*destructor)(void*),
458 const char* a, size_t alen,
459 const char* b, size_t blen),
460 const char* (*name)(void*)) {
461 leveldb_comparator_t* result = new leveldb_comparator_t;
462 result->state_ = state;
463 result->destructor_ = destructor;
464 result->compare_ = compare;
465 result->name_ = name;
469 void leveldb_comparator_destroy(leveldb_comparator_t* cmp) {
473 leveldb_filterpolicy_t* leveldb_filterpolicy_create(
475 void (*destructor)(void*),
476 char* (*create_filter)(
478 const char* const* key_array, const size_t* key_length_array,
480 size_t* filter_length),
481 unsigned char (*key_may_match)(
483 const char* key, size_t length,
484 const char* filter, size_t filter_length),
485 const char* (*name)(void*)) {
486 leveldb_filterpolicy_t* result = new leveldb_filterpolicy_t;
487 result->state_ = state;
488 result->destructor_ = destructor;
489 result->create_ = create_filter;
490 result->key_match_ = key_may_match;
491 result->name_ = name;
495 void leveldb_filterpolicy_destroy(leveldb_filterpolicy_t* filter) {
499 leveldb_filterpolicy_t* leveldb_filterpolicy_create_bloom(int bits_per_key) {
500 // Make a leveldb_filterpolicy_t, but override all of its methods so
501 // they delegate to a NewBloomFilterPolicy() instead of user
502 // supplied C functions.
503 struct Wrapper : public leveldb_filterpolicy_t {
504 const FilterPolicy* rep_;
505 ~Wrapper() { delete rep_; }
506 const char* Name() const { return rep_->Name(); }
507 void CreateFilter(const Slice* keys, int n, std::string* dst) const {
508 return rep_->CreateFilter(keys, n, dst);
510 bool KeyMayMatch(const Slice& key, const Slice& filter) const {
511 return rep_->KeyMayMatch(key, filter);
513 static void DoNothing(void*) { }
515 Wrapper* wrapper = new Wrapper;
516 wrapper->rep_ = NewBloomFilterPolicy(bits_per_key);
517 wrapper->state_ = NULL;
518 wrapper->destructor_ = &Wrapper::DoNothing;
522 leveldb_readoptions_t* leveldb_readoptions_create() {
523 return new leveldb_readoptions_t;
526 void leveldb_readoptions_destroy(leveldb_readoptions_t* opt) {
530 void leveldb_readoptions_set_verify_checksums(
531 leveldb_readoptions_t* opt,
533 opt->rep.verify_checksums = v;
536 void leveldb_readoptions_set_fill_cache(
537 leveldb_readoptions_t* opt, unsigned char v) {
538 opt->rep.fill_cache = v;
541 void leveldb_readoptions_set_snapshot(
542 leveldb_readoptions_t* opt,
543 const leveldb_snapshot_t* snap) {
544 opt->rep.snapshot = (snap ? snap->rep : NULL);
547 leveldb_writeoptions_t* leveldb_writeoptions_create() {
548 return new leveldb_writeoptions_t;
551 void leveldb_writeoptions_destroy(leveldb_writeoptions_t* opt) {
555 void leveldb_writeoptions_set_sync(
556 leveldb_writeoptions_t* opt, unsigned char v) {
560 leveldb_cache_t* leveldb_cache_create_lru(size_t capacity) {
561 leveldb_cache_t* c = new leveldb_cache_t;
562 c->rep = NewLRUCache(capacity);
566 void leveldb_cache_destroy(leveldb_cache_t* cache) {
571 leveldb_env_t* leveldb_create_default_env() {
572 leveldb_env_t* result = new leveldb_env_t;
573 result->rep = Env::Default();
574 result->is_default = true;
578 void leveldb_env_destroy(leveldb_env_t* env) {
579 if (!env->is_default) delete env->rep;
583 void leveldb_free(void* ptr) {
587 int leveldb_major_version() {
588 return kMajorVersion;
591 int leveldb_minor_version() {
592 return kMinorVersion;