LevelDB C API 整理分类

// 结构体列表
typedef struct leveldb_t leveldb_t; // 数据库
typedef struct leveldb_cache_t leveldb_cache_t; // 缓存
typedef struct leveldb_comparator_t leveldb_comparator_t; // 比较器
typedef struct leveldb_env_t leveldb_env_t; // 环境
typedef struct leveldb_filelock_t leveldb_filelock_t; // 文件锁
typedef struct leveldb_filterpolicy_t leveldb_filterpolicy_t; // 过滤器
typedef struct leveldb_iterator_t leveldb_iterator_t; // 迭代器
typedef struct leveldb_logger_t leveldb_logger_t; // 日志
typedef struct leveldb_options_t leveldb_options_t; // 选项
typedef struct leveldb_randomfile_t leveldb_randomfile_t; //
typedef struct leveldb_readoptions_t leveldb_readoptions_t; // 读选项
typedef struct leveldb_seqfile_t leveldb_seqfile_t; //
typedef struct leveldb_snapshot_t leveldb_snapshot_t; // 快照
typedef struct leveldb_writablefile_t leveldb_writablefile_t; //
typedef struct leveldb_writebatch_t leveldb_writebatch_t; // 批写入
typedef struct leveldb_writeoptions_t leveldb_writeoptions_t; // 写选项

// 函数列表

/************************************************************ 数据库API *********************************************************************/
// 打开数据库
extern leveldb_t* leveldb_open( const leveldb_options_t* options,const char* name,char** errptr);
// 关闭数据库
extern void leveldb_close(leveldb_t* db);
// 添加k-v
extern void leveldb_put(leveldb_t* db,const leveldb_writeoptions_t* options, const char* key, size_t keylen,const char* val, size_t vallen,char** errptr);
// 删除k-v
extern void leveldb_delete(leveldb_t* db,const leveldb_writeoptions_t* options,const char* key, size_t keylen,char** errptr);
// 原子性写入
extern void leveldb_write(leveldb_t* db,const leveldb_writeoptions_t* options,leveldb_writebatch_t* batch,char** errptr);
// 获取k-v
extern char* leveldb_get(leveldb_t* db,const leveldb_readoptions_t* options,const char* key, size_t keylen,size_t* vallen,char** errptr);
// 获取属性值
extern char* leveldb_property_value(leveldb_t* db,const char* propname);
// 获取数据库大概的大小
extern void leveldb_approximate_sizes(leveldb_t* db,int num_ranges,const char* const* range_start_key, const size_t* range_start_key_len,const char* const* range_limit_key, const size_t* range_limit_key_len,uint64_t* sizes);
// 范围压缩
extern void leveldb_compact_range(leveldb_t* db,const char* start_key, size_t start_key_len,const char* limit_key, size_t limit_key_len);
// 销毁数据库
extern void leveldb_destroy_db(const leveldb_options_t* options,const char* name,char** errptr);
// 修复数据库
extern void leveldb_repair_db(const leveldb_options_t* options,const char* name,char** errptr);
//
extern void leveldb_free(void* ptr);

/************************************************************ 迭代器API *********************************************************************/
// 创建迭代器
extern leveldb_iterator_t* leveldb_create_iterator(leveldb_t* db,const leveldb_readoptions_t* options);
extern void leveldb_iter_destroy(leveldb_iterator_t*);
extern unsigned char leveldb_iter_valid(const leveldb_iterator_t*);
extern void leveldb_iter_seek_to_first(leveldb_iterator_t*);
extern void leveldb_iter_seek_to_last(leveldb_iterator_t*);
extern void leveldb_iter_seek(leveldb_iterator_t*, const char* k, size_t klen);
extern void leveldb_iter_next(leveldb_iterator_t*);
extern void leveldb_iter_prev(leveldb_iterator_t*);
extern const char* leveldb_iter_key(const leveldb_iterator_t*, size_t* klen);
extern const char* leveldb_iter_value(const leveldb_iterator_t*, size_t* vlen);
extern void leveldb_iter_get_error(const leveldb_iterator_t*, char** errptr);

/************************************************************ 批量写入API *******************************************************************/
//
extern leveldb_writebatch_t* leveldb_writebatch_create();
extern void leveldb_writebatch_destroy(leveldb_writebatch_t*);
extern void leveldb_writebatch_clear(leveldb_writebatch_t*);
extern void leveldb_writebatch_put(leveldb_writebatch_t*,const char* key, size_t klen,const char* val, size_t vlen);
extern void leveldb_writebatch_delete(leveldb_writebatch_t*,const char* key, size_t klen);
extern void leveldb_writebatch_iterate(leveldb_writebatch_t*,void* state,void (*put)(void*, const char* k, size_t klen, const char* v, size_t vlen),void (*deleted)(void*, const char* k, size_t klen));

/************************************************************** 选项器API *********************************************************************/
//
extern leveldb_options_t* leveldb_options_create();
extern void leveldb_options_destroy(leveldb_options_t*);
extern void leveldb_options_set_comparator(leveldb_options_t*,leveldb_comparator_t*);
extern void leveldb_options_set_filter_policy(leveldb_options_t*,leveldb_filterpolicy_t*);
extern void leveldb_options_set_create_if_missing(leveldb_options_t*, unsigned char);
extern void leveldb_options_set_error_if_exists(leveldb_options_t*, unsigned char);
extern void leveldb_options_set_paranoid_checks(leveldb_options_t*, unsigned char);
extern void leveldb_options_set_env(leveldb_options_t*, leveldb_env_t*);
extern void leveldb_options_set_info_log(leveldb_options_t*, leveldb_logger_t*);
extern void leveldb_options_set_write_buffer_size(leveldb_options_t*, size_t);
extern void leveldb_options_set_max_open_files(leveldb_options_t*, int);
extern void leveldb_options_set_cache(leveldb_options_t*, leveldb_cache_t*);
extern void leveldb_options_set_block_size(leveldb_options_t*, size_t);
extern void leveldb_options_set_block_restart_interval(leveldb_options_t*, int);

enum {
leveldb_no_compression = 0,
leveldb_snappy_compression = 1
};
extern void leveldb_options_set_compression(leveldb_options_t*, int);

/************************************************************** 比较器API *********************************************************************/
//
extern leveldb_comparator_t* leveldb_comparator_create(
void* state,
void (*destructor)(void*),
int (*compare)(
void*,
const char* a, size_t alen,
const char* b, size_t blen),
const char* (*name)(void*));
extern void leveldb_comparator_destroy(leveldb_comparator_t*);

/************************************************************** 过滤器API *********************************************************************/
//
extern leveldb_filterpolicy_t* leveldb_filterpolicy_create(
void* state,
void (*destructor)(void*),
char* (*create_filter)(
void*,
const char* const* key_array, const size_t* key_length_array,
int num_keys,
size_t* filter_length),
unsigned char (*key_may_match)(
void*,
const char* key, size_t length,
const char* filter, size_t filter_length),
const char* (*name)(void*));
extern void leveldb_filterpolicy_destroy(leveldb_filterpolicy_t*);

extern leveldb_filterpolicy_t* leveldb_filterpolicy_create_bloom(int bits_per_key);

/************************************************************** 读选项API *********************************************************************/
//
extern leveldb_readoptions_t* leveldb_readoptions_create();
extern void leveldb_readoptions_destroy(leveldb_readoptions_t*);
extern void leveldb_readoptions_set_verify_checksums(leveldb_readoptions_t*,unsigned char);
extern void leveldb_readoptions_set_fill_cache(leveldb_readoptions_t*, unsigned char);
extern void leveldb_readoptions_set_snapshot(leveldb_readoptions_t*,const leveldb_snapshot_t*);

/************************************************************** 写选项API *********************************************************************/
// 创建写入选项变量
extern leveldb_writeoptions_t* leveldb_writeoptions_create();
// 销毁
extern void leveldb_writeoptions_destroy(leveldb_writeoptions_t*);
// 设置写入选项是否异步方式写入
extern void leveldb_writeoptions_set_sync(leveldb_writeoptions_t*, unsigned char);

/**************************************************************** 缓存API *********************************************************************/
// 安居lru算法创建缓存
extern leveldb_cache_t* leveldb_cache_create_lru(size_t capacity);
// 销毁缓存
extern void leveldb_cache_destroy(leveldb_cache_t* cache);

/************************************************************ 环境API **********************************************************************/
// 创建默认环境变量
extern leveldb_env_t* leveldb_create_default_env();
// 销毁环境变量
extern void leveldb_env_destroy(leveldb_env_t*);

/************************************************************ 快照API **********************************************************************/
// 创建快照
extern const leveldb_snapshot_t* leveldb_create_snapshot(leveldb_t* db);
// 将快照和数据库关联
extern void leveldb_release_snapshot(leveldb_t* db,const leveldb_snapshot_t* snapshot);

/************************************************************ 工具API **********************************************************************/
// 获取主版本好
extern int leveldb_major_version();
// 获取子版本号
extern int leveldb_minor_version();