extmod/modbtree.c - lite/micropython - Linaro Git Browser

 /*
  * This file is part of the MicroPython project, http://micropython.org/
  *
  * The MIT License (MIT)
  *
  * Copyright (c) 2016 Paul Sokolovsky
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in
  * all copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  * THE SOFTWARE.
  */

 #include <stdio.h>
 #include <string.h>
 #include <errno.h> // for declaration of global errno variable
 #include <fcntl.h>

 #include "py/runtime.h"
 #include "py/stream.h"

 #if MICROPY_PY_BTREE

 #include <db.h>
 #include <../../btree/btree.h>

 typedef struct _mp_obj_btree_t {
     mp_obj_base_t base;
     DB *db;
     mp_obj_t start_key;
     mp_obj_t end_key;
     #define FLAG_END_KEY_INCL 1
     #define FLAG_DESC 2
     #define FLAG_ITER_TYPE_MASK 0xc0
     #define FLAG_ITER_KEYS   0x40
     #define FLAG_ITER_VALUES 0x80
     #define FLAG_ITER_ITEMS  0xc0
     byte flags;
     byte next_flags;
 } mp_obj_btree_t;

 #if !MICROPY_ENABLE_DYNRUNTIME
 STATIC const mp_obj_type_t btree_type;
 #endif

 #define CHECK_ERROR(res) \
     if (res == RET_ERROR) { \
         mp_raise_OSError(errno); \
     }

 void __dbpanic(DB *db) {
     mp_printf(&mp_plat_print, "__dbpanic(%p)\n", db);
 }

 STATIC mp_obj_btree_t *btree_new(DB *db) {
     mp_obj_btree_t *o = m_new_obj(mp_obj_btree_t);
     o->base.type = &btree_type;
     o->db = db;
     o->start_key = mp_const_none;
     o->end_key = mp_const_none;
     o->next_flags = 0;
     return o;
 }

 STATIC void btree_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
     (void)kind;
     mp_obj_btree_t *self = MP_OBJ_TO_PTR(self_in);
     mp_printf(print, "<btree %p>", self->db);
 }

 STATIC mp_obj_t btree_flush(mp_obj_t self_in) {
     mp_obj_btree_t *self = MP_OBJ_TO_PTR(self_in);
     return MP_OBJ_NEW_SMALL_INT(__bt_sync(self->db, 0));
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(btree_flush_obj, btree_flush);

 STATIC mp_obj_t btree_close(mp_obj_t self_in) {
     mp_obj_btree_t *self = MP_OBJ_TO_PTR(self_in);
     return MP_OBJ_NEW_SMALL_INT(__bt_close(self->db));
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_1(btree_close_obj, btree_close);

 STATIC mp_obj_t btree_put(size_t n_args, const mp_obj_t *args) {
     (void)n_args;
     mp_obj_btree_t *self = MP_OBJ_TO_PTR(args[0]);
     DBT key, val;
     key.data = (void *)mp_obj_str_get_data(args[1], &key.size);
     val.data = (void *)mp_obj_str_get_data(args[2], &val.size);
     return MP_OBJ_NEW_SMALL_INT(__bt_put(self->db, &key, &val, 0));
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(btree_put_obj, 3, 4, btree_put);

 STATIC mp_obj_t btree_get(size_t n_args, const mp_obj_t *args) {
     mp_obj_btree_t *self = MP_OBJ_TO_PTR(args[0]);
     DBT key, val;
     key.data = (void *)mp_obj_str_get_data(args[1], &key.size);
     int res = __bt_get(self->db, &key, &val, 0);
     if (res == RET_SPECIAL) {
         if (n_args > 2) {
             return args[2];
         } else {
             return mp_const_none;
         }
     }
     CHECK_ERROR(res);
     return mp_obj_new_bytes(val.data, val.size);
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(btree_get_obj, 2, 3, btree_get);

 STATIC mp_obj_t btree_seq(size_t n_args, const mp_obj_t *args) {
     mp_obj_btree_t *self = MP_OBJ_TO_PTR(args[0]);
     int flags = MP_OBJ_SMALL_INT_VALUE(args[1]);
     DBT key, val;
     if (n_args > 2) {
         key.data = (void *)mp_obj_str_get_data(args[2], &key.size);
     }

     int res = __bt_seq(self->db, &key, &val, flags);
     CHECK_ERROR(res);
     if (res == RET_SPECIAL) {
         return mp_const_none;
     }

     mp_obj_t pair_o = mp_obj_new_tuple(2, NULL);
     mp_obj_tuple_t *pair = MP_OBJ_TO_PTR(pair_o);
     pair->items[0] = mp_obj_new_bytes(key.data, key.size);
     pair->items[1] = mp_obj_new_bytes(val.data, val.size);
     return pair_o;
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(btree_seq_obj, 2, 4, btree_seq);

 STATIC mp_obj_t btree_init_iter(size_t n_args, const mp_obj_t *args, byte type) {
     mp_obj_btree_t *self = MP_OBJ_TO_PTR(args[0]);
     self->next_flags = type;
     self->start_key = mp_const_none;
     self->end_key = mp_const_none;
     if (n_args > 1) {
         self->start_key = args[1];
         if (n_args > 2) {
             self->end_key = args[2];
             if (n_args > 3) {
                 self->next_flags = type | MP_OBJ_SMALL_INT_VALUE(args[3]);
             }
         }
     }
     return args[0];
 }

 STATIC mp_obj_t btree_keys(size_t n_args, const mp_obj_t *args) {
     return btree_init_iter(n_args, args, FLAG_ITER_KEYS);
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(btree_keys_obj, 1, 4, btree_keys);

 STATIC mp_obj_t btree_values(size_t n_args, const mp_obj_t *args) {
     return btree_init_iter(n_args, args, FLAG_ITER_VALUES);
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(btree_values_obj, 1, 4, btree_values);

 STATIC mp_obj_t btree_items(size_t n_args, const mp_obj_t *args) {
     return btree_init_iter(n_args, args, FLAG_ITER_ITEMS);
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(btree_items_obj, 1, 4, btree_items);

 STATIC mp_obj_t btree_getiter(mp_obj_t self_in, mp_obj_iter_buf_t *iter_buf) {
     (void)iter_buf;
     mp_obj_btree_t *self = MP_OBJ_TO_PTR(self_in);
     if (self->next_flags != 0) {
         // If we're called immediately after keys(), values(), or items(),
         // use their setup for iteration.
         self->flags = self->next_flags;
         self->next_flags = 0;
     } else {
         // Otherwise, iterate over all keys.
         self->flags = FLAG_ITER_KEYS;
         self->start_key = mp_const_none;
         self->end_key = mp_const_none;
     }

     return self_in;
 }

 STATIC mp_obj_t btree_iternext(mp_obj_t self_in) {
     mp_obj_btree_t *self = MP_OBJ_TO_PTR(self_in);
     DBT key, val;
     int res;
     bool desc = self->flags & FLAG_DESC;
     if (self->start_key != MP_OBJ_NULL) {
         int flags = R_FIRST;
         if (self->start_key != mp_const_none) {
             key.data = (void *)mp_obj_str_get_data(self->start_key, &key.size);
             flags = R_CURSOR;
         } else if (desc) {
             flags = R_LAST;
         }
         res = __bt_seq(self->db, &key, &val, flags);
         self->start_key = MP_OBJ_NULL;
     } else {
         res = __bt_seq(self->db, &key, &val, desc ? R_PREV : R_NEXT);
     }

     if (res == RET_SPECIAL) {
         return MP_OBJ_STOP_ITERATION;
     }
     CHECK_ERROR(res);

     if (self->end_key != mp_const_none) {
         DBT end_key;
         end_key.data = (void *)mp_obj_str_get_data(self->end_key, &end_key.size);
         BTREE *t = self->db->internal;
         int cmp = t->bt_cmp(&key, &end_key);
         if (desc) {
             cmp = -cmp;
         }
         if (self->flags & FLAG_END_KEY_INCL) {
             cmp--;
         }
         if (cmp >= 0) {
             self->end_key = MP_OBJ_NULL;
             return MP_OBJ_STOP_ITERATION;
         }
     }

     switch (self->flags & FLAG_ITER_TYPE_MASK) {
         case FLAG_ITER_KEYS:
             return mp_obj_new_bytes(key.data, key.size);
         case FLAG_ITER_VALUES:
             return mp_obj_new_bytes(val.data, val.size);
         default: {
             mp_obj_t pair_o = mp_obj_new_tuple(2, NULL);
             mp_obj_tuple_t *pair = MP_OBJ_TO_PTR(pair_o);
             pair->items[0] = mp_obj_new_bytes(key.data, key.size);
             pair->items[1] = mp_obj_new_bytes(val.data, val.size);
             return pair_o;
         }
     }
 }

 STATIC mp_obj_t btree_subscr(mp_obj_t self_in, mp_obj_t index, mp_obj_t value) {
     mp_obj_btree_t *self = MP_OBJ_TO_PTR(self_in);
     if (value == MP_OBJ_NULL) {
         // delete
         DBT key;
         key.data = (void *)mp_obj_str_get_data(index, &key.size);
         int res = __bt_delete(self->db, &key, 0);
         if (res == RET_SPECIAL) {
             mp_raise_type(&mp_type_KeyError);
         }
         CHECK_ERROR(res);
         return mp_const_none;
     } else if (value == MP_OBJ_SENTINEL) {
         // load
         DBT key, val;
         key.data = (void *)mp_obj_str_get_data(index, &key.size);
         int res = __bt_get(self->db, &key, &val, 0);
         if (res == RET_SPECIAL) {
             mp_raise_type(&mp_type_KeyError);
         }
         CHECK_ERROR(res);
         return mp_obj_new_bytes(val.data, val.size);
     } else {
         // store
         DBT key, val;
         key.data = (void *)mp_obj_str_get_data(index, &key.size);
         val.data = (void *)mp_obj_str_get_data(value, &val.size);
         int res = __bt_put(self->db, &key, &val, 0);
         CHECK_ERROR(res);
         return mp_const_none;
     }
 }

 STATIC mp_obj_t btree_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
     mp_obj_btree_t *self = MP_OBJ_TO_PTR(lhs_in);
     switch (op) {
         case MP_BINARY_OP_CONTAINS: {
             DBT key, val;
             key.data = (void *)mp_obj_str_get_data(rhs_in, &key.size);
             int res = __bt_get(self->db, &key, &val, 0);
             CHECK_ERROR(res);
             return mp_obj_new_bool(res != RET_SPECIAL);
         }
         default:
             // op not supported
             return MP_OBJ_NULL;
     }
 }

 #if !MICROPY_ENABLE_DYNRUNTIME
 STATIC const mp_rom_map_elem_t btree_locals_dict_table[] = {
     { MP_ROM_QSTR(MP_QSTR_close), MP_ROM_PTR(&btree_close_obj) },
     { MP_ROM_QSTR(MP_QSTR_flush), MP_ROM_PTR(&btree_flush_obj) },
     { MP_ROM_QSTR(MP_QSTR_get), MP_ROM_PTR(&btree_get_obj) },
     { MP_ROM_QSTR(MP_QSTR_put), MP_ROM_PTR(&btree_put_obj) },
     { MP_ROM_QSTR(MP_QSTR_seq), MP_ROM_PTR(&btree_seq_obj) },
     { MP_ROM_QSTR(MP_QSTR_keys), MP_ROM_PTR(&btree_keys_obj) },
     { MP_ROM_QSTR(MP_QSTR_values), MP_ROM_PTR(&btree_values_obj) },
     { MP_ROM_QSTR(MP_QSTR_items), MP_ROM_PTR(&btree_items_obj) },
 };

 STATIC MP_DEFINE_CONST_DICT(btree_locals_dict, btree_locals_dict_table);

 STATIC const mp_obj_type_t btree_type = {
     { &mp_type_type },
     // Save on qstr's, reuse same as for module
     .name = MP_QSTR_btree,
     .print = btree_print,
     .getiter = btree_getiter,
     .iternext = btree_iternext,
     .binary_op = btree_binary_op,
     .subscr = btree_subscr,
     .locals_dict = (void *)&btree_locals_dict,
 };
 #endif

 STATIC const FILEVTABLE btree_stream_fvtable = {
     mp_stream_posix_read,
     mp_stream_posix_write,
     mp_stream_posix_lseek,
     mp_stream_posix_fsync
 };

 #if !MICROPY_ENABLE_DYNRUNTIME
 STATIC mp_obj_t mod_btree_open(size_t n_args, const mp_obj_t *pos_args, mp_map_t *kw_args) {
     static const mp_arg_t allowed_args[] = {
         { MP_QSTR_flags, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
         { MP_QSTR_cachesize, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
         { MP_QSTR_pagesize, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
         { MP_QSTR_minkeypage, MP_ARG_KW_ONLY | MP_ARG_INT, {.u_int = 0} },
     };

     // Make sure we got a stream object
     mp_get_stream_raise(pos_args[0], MP_STREAM_OP_READ | MP_STREAM_OP_WRITE | MP_STREAM_OP_IOCTL);

     struct {
         mp_arg_val_t flags;
         mp_arg_val_t cachesize;
         mp_arg_val_t pagesize;
         mp_arg_val_t minkeypage;
     } args;
     mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args,
         MP_ARRAY_SIZE(allowed_args), allowed_args, (mp_arg_val_t *)&args);
     BTREEINFO openinfo = {0};
     openinfo.flags = args.flags.u_int;
     openinfo.cachesize = args.cachesize.u_int;
     openinfo.psize = args.pagesize.u_int;
     openinfo.minkeypage = args.minkeypage.u_int;

     DB *db = __bt_open(MP_OBJ_TO_PTR(pos_args[0]), &btree_stream_fvtable, &openinfo, /*dflags*/ 0);
     if (db == NULL) {
         mp_raise_OSError(errno);
     }
     return MP_OBJ_FROM_PTR(btree_new(db));
 }
 STATIC MP_DEFINE_CONST_FUN_OBJ_KW(mod_btree_open_obj, 1, mod_btree_open);

 STATIC const mp_rom_map_elem_t mp_module_btree_globals_table[] = {
     { MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_btree) },
     { MP_ROM_QSTR(MP_QSTR_open), MP_ROM_PTR(&mod_btree_open_obj) },
     { MP_ROM_QSTR(MP_QSTR_INCL), MP_ROM_INT(FLAG_END_KEY_INCL) },
     { MP_ROM_QSTR(MP_QSTR_DESC), MP_ROM_INT(FLAG_DESC) },
 };

 STATIC MP_DEFINE_CONST_DICT(mp_module_btree_globals, mp_module_btree_globals_table);

 const mp_obj_module_t mp_module_btree = {
     .base = { &mp_type_module },
     .globals = (mp_obj_dict_t *)&mp_module_btree_globals,
 };
 #endif

 #endif // MICROPY_PY_BTREE
	/*
	* This file is part of the MicroPython project, http://micropython.org/
	*
	* The MIT License (MIT)
	*
	* Copyright (c) 2016 Paul Sokolovsky
	*
	* Permission is hereby granted, free of charge, to any person obtaining a copy
	* of this software and associated documentation files (the "Software"), to deal
	* in the Software without restriction, including without limitation the rights
	* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	* copies of the Software, and to permit persons to whom the Software is
	* furnished to do so, subject to the following conditions:
	*
	* The above copyright notice and this permission notice shall be included in
	* all copies or substantial portions of the Software.
	*
	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
	* THE SOFTWARE.
	*/

	#include <stdio.h>
	#include <string.h>
	#include <errno.h> // for declaration of global errno variable
	#include <fcntl.h>

	#include "py/runtime.h"
	#include "py/stream.h"

	#if MICROPY_PY_BTREE

	#include <db.h>
	#include <../../btree/btree.h>

	typedef struct _mp_obj_btree_t {
	mp_obj_base_t base;
	DB *db;
	mp_obj_t start_key;
	mp_obj_t end_key;
	#define FLAG_END_KEY_INCL 1
	#define FLAG_DESC 2
	#define FLAG_ITER_TYPE_MASK 0xc0
	#define FLAG_ITER_KEYS 0x40
	#define FLAG_ITER_VALUES 0x80
	#define FLAG_ITER_ITEMS 0xc0
	byte flags;
	byte next_flags;
	} mp_obj_btree_t;

	#if !MICROPY_ENABLE_DYNRUNTIME
	STATIC const mp_obj_type_t btree_type;
	#endif

	#define CHECK_ERROR(res) \
	if (res == RET_ERROR) { \
	mp_raise_OSError(errno); \
	}

	void __dbpanic(DB *db) {
	mp_printf(&mp_plat_print, "__dbpanic(%p)\n", db);
	}

	STATIC mp_obj_btree_t btree_new(DB db) {
	mp_obj_btree_t *o = m_new_obj(mp_obj_btree_t);
	o->base.type = &btree_type;
	o->db = db;
	o->start_key = mp_const_none;
	o->end_key = mp_const_none;
	o->next_flags = 0;
	return o;
	}

	STATIC void btree_print(const mp_print_t *print, mp_obj_t self_in, mp_print_kind_t kind) {
	(void)kind;
	mp_obj_btree_t *self = MP_OBJ_TO_PTR(self_in);
	mp_printf(print, "<btree %p>", self->db);
	}

	STATIC mp_obj_t btree_flush(mp_obj_t self_in) {
	mp_obj_btree_t *self = MP_OBJ_TO_PTR(self_in);
	return MP_OBJ_NEW_SMALL_INT(__bt_sync(self->db, 0));
	}
	STATIC MP_DEFINE_CONST_FUN_OBJ_1(btree_flush_obj, btree_flush);

	STATIC mp_obj_t btree_close(mp_obj_t self_in) {
	mp_obj_btree_t *self = MP_OBJ_TO_PTR(self_in);
	return MP_OBJ_NEW_SMALL_INT(__bt_close(self->db));
	}
	STATIC MP_DEFINE_CONST_FUN_OBJ_1(btree_close_obj, btree_close);

	STATIC mp_obj_t btree_put(size_t n_args, const mp_obj_t *args) {
	(void)n_args;
	mp_obj_btree_t *self = MP_OBJ_TO_PTR(args[0]);
	DBT key, val;
	key.data = (void *)mp_obj_str_get_data(args[1], &key.size);
	val.data = (void *)mp_obj_str_get_data(args[2], &val.size);
	return MP_OBJ_NEW_SMALL_INT(__bt_put(self->db, &key, &val, 0));
	}
	STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(btree_put_obj, 3, 4, btree_put);

	STATIC mp_obj_t btree_get(size_t n_args, const mp_obj_t *args) {
	mp_obj_btree_t *self = MP_OBJ_TO_PTR(args[0]);
	DBT key, val;
	key.data = (void *)mp_obj_str_get_data(args[1], &key.size);
	int res = __bt_get(self->db, &key, &val, 0);
	if (res == RET_SPECIAL) {
	if (n_args > 2) {
	return args[2];
	} else {
	return mp_const_none;
	}
	}
	CHECK_ERROR(res);
	return mp_obj_new_bytes(val.data, val.size);
	}
	STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(btree_get_obj, 2, 3, btree_get);

	STATIC mp_obj_t btree_seq(size_t n_args, const mp_obj_t *args) {
	mp_obj_btree_t *self = MP_OBJ_TO_PTR(args[0]);
	int flags = MP_OBJ_SMALL_INT_VALUE(args[1]);
	DBT key, val;
	if (n_args > 2) {
	key.data = (void *)mp_obj_str_get_data(args[2], &key.size);
	}

	int res = __bt_seq(self->db, &key, &val, flags);
	CHECK_ERROR(res);
	if (res == RET_SPECIAL) {
	return mp_const_none;
	}

	mp_obj_t pair_o = mp_obj_new_tuple(2, NULL);
	mp_obj_tuple_t *pair = MP_OBJ_TO_PTR(pair_o);
	pair->items[0] = mp_obj_new_bytes(key.data, key.size);
	pair->items[1] = mp_obj_new_bytes(val.data, val.size);
	return pair_o;
	}
	STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(btree_seq_obj, 2, 4, btree_seq);

	STATIC mp_obj_t btree_init_iter(size_t n_args, const mp_obj_t *args, byte type) {
	mp_obj_btree_t *self = MP_OBJ_TO_PTR(args[0]);
	self->next_flags = type;
	self->start_key = mp_const_none;
	self->end_key = mp_const_none;
	if (n_args > 1) {
	self->start_key = args[1];
	if (n_args > 2) {
	self->end_key = args[2];
	if (n_args > 3) {
	self->next_flags = type \| MP_OBJ_SMALL_INT_VALUE(args[3]);
	}
	}
	}
	return args[0];
	}

	STATIC mp_obj_t btree_keys(size_t n_args, const mp_obj_t *args) {
	return btree_init_iter(n_args, args, FLAG_ITER_KEYS);
	}
	STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(btree_keys_obj, 1, 4, btree_keys);

	STATIC mp_obj_t btree_values(size_t n_args, const mp_obj_t *args) {
	return btree_init_iter(n_args, args, FLAG_ITER_VALUES);
	}
	STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(btree_values_obj, 1, 4, btree_values);

	STATIC mp_obj_t btree_items(size_t n_args, const mp_obj_t *args) {
	return btree_init_iter(n_args, args, FLAG_ITER_ITEMS);
	}
	STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(btree_items_obj, 1, 4, btree_items);

	STATIC mp_obj_t btree_getiter(mp_obj_t self_in, mp_obj_iter_buf_t *iter_buf) {
	(void)iter_buf;
	mp_obj_btree_t *self = MP_OBJ_TO_PTR(self_in);
	if (self->next_flags != 0) {
	// If we're called immediately after keys(), values(), or items(),
	// use their setup for iteration.
	self->flags = self->next_flags;
	self->next_flags = 0;
	} else {
	// Otherwise, iterate over all keys.
	self->flags = FLAG_ITER_KEYS;
	self->start_key = mp_const_none;
	self->end_key = mp_const_none;
	}

	return self_in;
	}

	STATIC mp_obj_t btree_iternext(mp_obj_t self_in) {
	mp_obj_btree_t *self = MP_OBJ_TO_PTR(self_in);
	DBT key, val;
	int res;
	bool desc = self->flags & FLAG_DESC;
	if (self->start_key != MP_OBJ_NULL) {
	int flags = R_FIRST;
	if (self->start_key != mp_const_none) {
	key.data = (void *)mp_obj_str_get_data(self->start_key, &key.size);
	flags = R_CURSOR;
	} else if (desc) {
	flags = R_LAST;
	}
	res = __bt_seq(self->db, &key, &val, flags);
	self->start_key = MP_OBJ_NULL;
	} else {
	res = __bt_seq(self->db, &key, &val, desc ? R_PREV : R_NEXT);
	}

	if (res == RET_SPECIAL) {
	return MP_OBJ_STOP_ITERATION;
	}
	CHECK_ERROR(res);

	if (self->end_key != mp_const_none) {
	DBT end_key;
	end_key.data = (void *)mp_obj_str_get_data(self->end_key, &end_key.size);
	BTREE *t = self->db->internal;
	int cmp = t->bt_cmp(&key, &end_key);
	if (desc) {
	cmp = -cmp;
	}
	if (self->flags & FLAG_END_KEY_INCL) {
	cmp--;
	}
	if (cmp >= 0) {
	self->end_key = MP_OBJ_NULL;
	return MP_OBJ_STOP_ITERATION;
	}
	}

	switch (self->flags & FLAG_ITER_TYPE_MASK) {
	case FLAG_ITER_KEYS:
	return mp_obj_new_bytes(key.data, key.size);
	case FLAG_ITER_VALUES:
	return mp_obj_new_bytes(val.data, val.size);
	default: {
	mp_obj_t pair_o = mp_obj_new_tuple(2, NULL);
	mp_obj_tuple_t *pair = MP_OBJ_TO_PTR(pair_o);
	pair->items[0] = mp_obj_new_bytes(key.data, key.size);
	pair->items[1] = mp_obj_new_bytes(val.data, val.size);
	return pair_o;
	}
	}
	}

	STATIC mp_obj_t btree_subscr(mp_obj_t self_in, mp_obj_t index, mp_obj_t value) {
	mp_obj_btree_t *self = MP_OBJ_TO_PTR(self_in);
	if (value == MP_OBJ_NULL) {
	// delete
	DBT key;
	key.data = (void *)mp_obj_str_get_data(index, &key.size);
	int res = __bt_delete(self->db, &key, 0);
	if (res == RET_SPECIAL) {
	mp_raise_type(&mp_type_KeyError);
	}
	CHECK_ERROR(res);
	return mp_const_none;
	} else if (value == MP_OBJ_SENTINEL) {
	// load
	DBT key, val;
	key.data = (void *)mp_obj_str_get_data(index, &key.size);
	int res = __bt_get(self->db, &key, &val, 0);
	if (res == RET_SPECIAL) {
	mp_raise_type(&mp_type_KeyError);
	}
	CHECK_ERROR(res);
	return mp_obj_new_bytes(val.data, val.size);
	} else {
	// store
	DBT key, val;
	key.data = (void *)mp_obj_str_get_data(index, &key.size);
	val.data = (void *)mp_obj_str_get_data(value, &val.size);
	int res = __bt_put(self->db, &key, &val, 0);
	CHECK_ERROR(res);
	return mp_const_none;
	}
	}

	STATIC mp_obj_t btree_binary_op(mp_binary_op_t op, mp_obj_t lhs_in, mp_obj_t rhs_in) {
	mp_obj_btree_t *self = MP_OBJ_TO_PTR(lhs_in);
	switch (op) {
	case MP_BINARY_OP_CONTAINS: {
	DBT key, val;
	key.data = (void *)mp_obj_str_get_data(rhs_in, &key.size);
	int res = __bt_get(self->db, &key, &val, 0);
	CHECK_ERROR(res);
	return mp_obj_new_bool(res != RET_SPECIAL);
	}
	default:
	// op not supported
	return MP_OBJ_NULL;
	}
	}

	#if !MICROPY_ENABLE_DYNRUNTIME
	STATIC const mp_rom_map_elem_t btree_locals_dict_table[] = {
	{ MP_ROM_QSTR(MP_QSTR_close), MP_ROM_PTR(&btree_close_obj) },
	{ MP_ROM_QSTR(MP_QSTR_flush), MP_ROM_PTR(&btree_flush_obj) },
	{ MP_ROM_QSTR(MP_QSTR_get), MP_ROM_PTR(&btree_get_obj) },
	{ MP_ROM_QSTR(MP_QSTR_put), MP_ROM_PTR(&btree_put_obj) },
	{ MP_ROM_QSTR(MP_QSTR_seq), MP_ROM_PTR(&btree_seq_obj) },
	{ MP_ROM_QSTR(MP_QSTR_keys), MP_ROM_PTR(&btree_keys_obj) },
	{ MP_ROM_QSTR(MP_QSTR_values), MP_ROM_PTR(&btree_values_obj) },
	{ MP_ROM_QSTR(MP_QSTR_items), MP_ROM_PTR(&btree_items_obj) },
	};

	STATIC MP_DEFINE_CONST_DICT(btree_locals_dict, btree_locals_dict_table);

	STATIC const mp_obj_type_t btree_type = {
	{ &mp_type_type },
	// Save on qstr's, reuse same as for module
	.name = MP_QSTR_btree,
	.print = btree_print,
	.getiter = btree_getiter,
	.iternext = btree_iternext,
	.binary_op = btree_binary_op,
	.subscr = btree_subscr,
	.locals_dict = (void *)&btree_locals_dict,
	};
	#endif

	STATIC const FILEVTABLE btree_stream_fvtable = {
	mp_stream_posix_read,
	mp_stream_posix_write,
	mp_stream_posix_lseek,
	mp_stream_posix_fsync
	};

	#if !MICROPY_ENABLE_DYNRUNTIME
	STATIC mp_obj_t mod_btree_open(size_t n_args, const mp_obj_t pos_args, mp_map_t kw_args) {
	static const mp_arg_t allowed_args[] = {
	{ MP_QSTR_flags, MP_ARG_KW_ONLY \| MP_ARG_INT, {.u_int = 0} },
	{ MP_QSTR_cachesize, MP_ARG_KW_ONLY \| MP_ARG_INT, {.u_int = 0} },
	{ MP_QSTR_pagesize, MP_ARG_KW_ONLY \| MP_ARG_INT, {.u_int = 0} },
	{ MP_QSTR_minkeypage, MP_ARG_KW_ONLY \| MP_ARG_INT, {.u_int = 0} },
	};

	// Make sure we got a stream object
	mp_get_stream_raise(pos_args[0], MP_STREAM_OP_READ \| MP_STREAM_OP_WRITE \| MP_STREAM_OP_IOCTL);

	struct {
	mp_arg_val_t flags;
	mp_arg_val_t cachesize;
	mp_arg_val_t pagesize;
	mp_arg_val_t minkeypage;
	} args;
	mp_arg_parse_all(n_args - 1, pos_args + 1, kw_args,
	MP_ARRAY_SIZE(allowed_args), allowed_args, (mp_arg_val_t *)&args);
	BTREEINFO openinfo = {0};
	openinfo.flags = args.flags.u_int;
	openinfo.cachesize = args.cachesize.u_int;
	openinfo.psize = args.pagesize.u_int;
	openinfo.minkeypage = args.minkeypage.u_int;

	DB db = __bt_open(MP_OBJ_TO_PTR(pos_args[0]), &btree_stream_fvtable, &openinfo, /dflags*/ 0);
	if (db == NULL) {
	mp_raise_OSError(errno);
	}
	return MP_OBJ_FROM_PTR(btree_new(db));
	}
	STATIC MP_DEFINE_CONST_FUN_OBJ_KW(mod_btree_open_obj, 1, mod_btree_open);

	STATIC const mp_rom_map_elem_t mp_module_btree_globals_table[] = {
	{ MP_ROM_QSTR(MP_QSTR___name__), MP_ROM_QSTR(MP_QSTR_btree) },
	{ MP_ROM_QSTR(MP_QSTR_open), MP_ROM_PTR(&mod_btree_open_obj) },
	{ MP_ROM_QSTR(MP_QSTR_INCL), MP_ROM_INT(FLAG_END_KEY_INCL) },
	{ MP_ROM_QSTR(MP_QSTR_DESC), MP_ROM_INT(FLAG_DESC) },
	};

	STATIC MP_DEFINE_CONST_DICT(mp_module_btree_globals, mp_module_btree_globals_table);

	const mp_obj_module_t mp_module_btree = {
	.base = { &mp_type_module },
	.globals = (mp_obj_dict_t *)&mp_module_btree_globals,
	};
	#endif

	#endif // MICROPY_PY_BTREE