static int
kvs_session_verify(WT_DATA_SOURCE *wtds,
WT_SESSION *session, const char *uri, WT_CONFIG_ARG *config)
{
DATA_SOURCE *ds;
DB *db;
WT_EXTENSION_API *wt_api;
int ret = 0;
const char *name;
(void)config; /* Unused parameters */
ds = (DATA_SOURCE *)wtds;
wt_api = ds->wt_api;
/* Get the object name */
if ((ret = uri2name(wt_api, session, uri, &name)) != 0)
return (ret);
if ((ret = single_thread(wtds, session, &ds->rwlock)) != 0)
return (ret);
if ((ret = db_create(&db, ds->dbenv, 0)) != 0)
ESET(wt_api,
session, WT_ERROR, "db_create: %s", db_strerror(ret));
else if ((ret = db->verify(db, name, NULL, NULL, 0)) != 0)
ESET(wt_api, session, WT_ERROR,
"Db.verify: %s: %s", uri, db_strerror(ret));
/* db handle is dead */
ETRET(unlock(wt_api, session, &ds->rwlock));
return (ret);
}
/*
* wiredtiger_extension_terminate --
* Shutdown the KVS connector code.
*/
int
wiredtiger_extension_terminate(WT_CONNECTION *connection)
{
DATA_SOURCE *p;
int ret, tret;
(void)connection; /* Unused parameters */
ret = writelock(NULL, &global_lock);
/* Start a flush on any open objects. */
for (p = data_source_head; p != NULL; p = p->next)
if ((tret = kvs_commit(p->kvs)) != 0)
ESET(NULL, WT_ERROR,
"kvs_commit: %s: %s", p->uri, kvs_strerror(tret));
/* Complain if any of the objects are in use. */
for (p = data_source_head; p != NULL; p = p->next)
if (p->open_cursors != 0)
ESET(NULL, WT_ERROR,
"%s: has open cursors during close", p->uri);
/* Close and discard the remaining objects. */
while ((p = data_source_head) != NULL) {
if ((tret = kvs_close(p->kvs)) != 0)
ESET(NULL, WT_ERROR,
"kvs_close: %s: %s", p->uri, kvs_strerror(tret));
data_source_head = p->next;
free(p->uri);
ETRET(lock_destroy(NULL, &p->lock));
free(p);
}
ETRET(unlock(NULL, &global_lock));
ETRET(lock_destroy(NULL, &global_lock));
wt_ext = NULL;
return (ret);
}
/*
* drop_data_source --
* Drop a data source from our list, closing any underlying KVS handle.
*/
static int
drop_data_source(WT_SESSION *session, const char *uri)
{
DATA_SOURCE *p, **ref;
int ret;
if ((ret = writelock(session, &global_lock)) != 0)
return (ret);
/* Search our list of objects for a match. */
for (ref = &data_source_head; (p = *ref) != NULL; p = p->next)
if (strcmp(p->uri, uri) == 0)
break;
/*
* If we don't find the URI in our object list, we're done.
* If the object is in use (it has open cursors), we can't drop it.
* Otherwise, drop it.
*/
if (p == NULL || p->open_cursors != 0) {
if (p != NULL)
ret = EBUSY;
} else {
if ((ret = kvs_close(p->kvs)) != 0)
ESET(session, WT_ERROR,
"kvs_close: %s: %s", uri, kvs_strerror(ret));
*ref = p->next;
free(p->uri);
ETRET(lock_destroy(session, &p->lock));
free(p);
}
ETRET(unlock(session, &global_lock));
return (ret);
}
/*
* kvs_recno_alloc --
* Allocate a new record number.
*/
static INLINE int
kvs_recno_alloc(WT_CURSOR *wt_cursor)
{
struct kvs_record *r;
CURSOR *cursor;
WT_SESSION *session;
int ret;
cursor = (CURSOR *)wt_cursor;
session = cursor->session;
r = &cursor->record;
/* Lock the data-source. */
if ((ret = writelock(session, &cursor->data_source->lock)) != 0)
return (ret);
/*
* If not yet tracking the maximum record number, read the last record
* from the object and figure it out.
*
* XXX
* There is still a race here. If another thread of control performs a
* WT_CURSOR::insert of an explicit record number (that is, the other
* cursor isn't configured for "append"), we could race. If we figure
* out the last record in the data-source is 37, then the other thread
* explicitly writes record 37, things will go badly. I don't want to
* lock the data-source on every update, so I'm leaving this until we
* write the transactional code, because that's going to change all of
* the locking in here.
*/
if (cursor->data_source->append_recno == 0) {
if ((ret = kvs_last(cursor->data_source->kvs,
&cursor->record, (unsigned long)0, (unsigned long)0)) != 0)
goto err;
if ((ret = wt_ext->struct_unpack(wt_ext, session,
r->key, sizeof(r->key),
"r", &cursor->data_source->append_recno)) != 0)
goto err;
}
wt_cursor->recno = ++cursor->data_source->append_recno;
err: ETRET(unlock(session, &cursor->data_source->lock));
return (ret);
}
/*
* kvs_session_truncate --
* WT_SESSION::truncate method.
*/
static int
kvs_session_truncate(WT_DATA_SOURCE *dsrc,
WT_SESSION *session, const char *uri, WT_CONFIG_ARG *config)
{
DATA_SOURCE *p;
int ret, tret;
(void)dsrc; /* Unused parameters */
/*
* Truncate should work even if the object is not yet opened: if we
* don't find it, open it. We loop because we could theoretically
* race with other threads creating/deleting the object.
*/
for (;;) {
if ((ret = writelock(session, &global_lock)) != 0)
return (ret);
/* Search our list of objects for a match. */
for (p = data_source_head; p != NULL; p = p->next)
if (strcmp(p->uri, uri) == 0)
break;
/* If we don't find the object, open it. */
if (p == NULL) {
if ((ret = unlock(session, &global_lock)) != 0)
return (ret);
if ((ret = open_data_source(session, uri, config)) != 0)
return (ret);
continue;
}
if (p->open_cursors == 0) {
if ((tret = kvs_truncate(p->kvs)) != 0)
ESET(NULL, WT_ERROR,
"kvs_truncate: %s: %s",
p->uri, kvs_strerror(tret));
} else
ret = EBUSY;
ETRET(unlock(session, &global_lock));
return (ret);
}
/* NOTREACHED */
}
static int
kvs_terminate(WT_DATA_SOURCE *wtds, WT_SESSION *session)
{
DB_ENV *dbenv;
DATA_SOURCE *ds;
WT_EXTENSION_API *wt_api;
int ret = 0;
ds = (DATA_SOURCE *)wtds;
wt_api = ds->wt_api;
dbenv = ds->dbenv;
if (dbenv != NULL && (ret = dbenv->close(dbenv, 0)) != 0)
ESET(wt_api,
session, WT_ERROR, "DbEnv.close: %s", db_strerror(ret));
ETRET(lock_destroy(wt_api, session, &ds->rwlock));
return (ret);
}
static int
kvs_session_truncate(WT_DATA_SOURCE *wtds,
WT_SESSION *session, const char *uri, WT_CONFIG_ARG *config)
{
DATA_SOURCE *ds;
DB *db;
WT_EXTENSION_API *wt_api;
int tret, ret = 0;
const char *name;
(void)config; /* Unused parameters */
ds = (DATA_SOURCE *)wtds;
wt_api = ds->wt_api;
/* Get the object name */
if ((ret = uri2name(wt_api, session, uri, &name)) != 0)
return (ret);
if ((ret = single_thread(wtds, session, &ds->rwlock)) != 0)
return (ret);
if ((ret = db_create(&db, ds->dbenv, 0)) != 0)
ESET(wt_api,
session, WT_ERROR, "db_create: %s", db_strerror(ret));
else {
if ((ret = db->open(db,
NULL, name, NULL, DB_UNKNOWN, DB_TRUNCATE, 0)) != 0)
ESET(wt_api, session, WT_ERROR,
"Db.open: %s", db_strerror(ret));
if ((tret = db->close(db, 0)) != 0)
ESET(wt_api, session, WT_ERROR,
"Db.close: %s", db_strerror(tret));
}
ETRET(unlock(wt_api, session, &ds->rwlock));
return (ret);
}
static int
kvs_session_open_cursor(WT_DATA_SOURCE *wtds, WT_SESSION *session,
const char *uri, WT_CONFIG_ARG *config, WT_CURSOR **new_cursor)
{
CURSOR_SOURCE *cursor;
DATA_SOURCE *ds;
DB *db;
WT_CONFIG_ITEM v;
WT_EXTENSION_API *wt_api;
int locked, ret;
const char *name;
ds = (DATA_SOURCE *)wtds;
wt_api = ds->wt_api;
locked = 0;
/* Get the object name */
if ((ret = uri2name(wt_api, session, uri, &name)) != 0)
return (ret);
/* Allocate the cursor */
if ((cursor = calloc(1, sizeof(CURSOR_SOURCE))) == NULL)
return (os_errno());
cursor->ds = (DATA_SOURCE *)wtds;
cursor->wt_api = wt_api;
/* Parse configuration */
if ((ret = wt_api->config_get(
wt_api, session, config, "append", &v)) != 0) {
ESET(wt_api, session, ret,
"append configuration: %s",
wt_api->strerror(wt_api, session, ret));
goto err;
}
cursor->config_append = v.val != 0;
if ((ret = wt_api->config_get(
wt_api, session, config, "overwrite", &v)) != 0) {
ESET(wt_api, session, ret,
"overwrite configuration: %s",
wt_api->strerror(wt_api, session, ret));
goto err;
}
cursor->config_overwrite = v.val != 0;
if ((ret = wt_api->config_get(
wt_api, session, config, "key_format", &v)) != 0) {
ESET(wt_api, session, ret,
"key_format configuration: %s",
wt_api->strerror(wt_api, session, ret));
goto err;
}
cursor->config_recno = v.len == 1 && v.str[0] == 'r';
if ((ret = wt_api->config_get(
wt_api, session, config, "value_format", &v)) != 0) {
ESET(wt_api, session, ret,
"value_format configuration: %s",
wt_api->strerror(wt_api, session, ret));
goto err;
}
cursor->config_bitfield =
v.len == 2 && isdigit((u_char)v.str[0]) && v.str[1] == 't';
if ((ret = writelock(wt_api, session, &ds->rwlock)) != 0)
goto err;
locked = 1;
/* Open the Berkeley DB cursor */
if ((ret = db_create(&cursor->db, ds->dbenv, 0)) != 0) {
ESET(wt_api,
session, WT_ERROR, "db_create: %s", db_strerror(ret));
goto err;
}
db = cursor->db;
if ((ret = db->open(db, NULL, name, NULL,
cursor->config_recno ? DB_RECNO : DB_BTREE, DB_CREATE, 0)) != 0) {
ESET(wt_api,
session, WT_ERROR, "Db.open: %s", db_strerror(ret));
goto err;
}
if ((ret = db->cursor(db, NULL, &cursor->dbc, 0)) != 0) {
ESET(wt_api,
session, WT_ERROR, "Db.cursor: %s", db_strerror(ret));
goto err;
}
/* Initialize the methods */
cursor->wtcursor.next = kvs_cursor_next;
cursor->wtcursor.prev = kvs_cursor_prev;
cursor->wtcursor.reset = kvs_cursor_reset;
cursor->wtcursor.search = kvs_cursor_search;
cursor->wtcursor.search_near = kvs_cursor_search_near;
cursor->wtcursor.insert = kvs_cursor_insert;
cursor->wtcursor.update = kvs_cursor_update;
cursor->wtcursor.remove = kvs_cursor_remove;
cursor->wtcursor.close = kvs_cursor_close;
*new_cursor = (WT_CURSOR *)cursor;
++ds->open_cursors;
if (0) {
err: free(cursor);
}
if (locked)
ETRET(unlock(wt_api, session, &ds->rwlock));
return (ret);
}
/*
* open_data_source --
* Open a new data source and insert it into the list.
*/
static int
open_data_source(WT_SESSION *session, const char *uri, WT_CONFIG_ARG *config)
{
struct kvs_config kvs_config;
DATA_SOURCE *data_source, *p;
int ds_lockinit, flags, locked, ret;
char **devices, *emsg;
devices = NULL;
emsg = NULL;
ds_lockinit = locked = ret = 0;
/*
* The first time we open a cursor on an object, allocate an underlying
* data source object.
*/
if ((data_source =
(DATA_SOURCE *)calloc(1, sizeof(DATA_SOURCE))) == NULL)
return (os_errno());
if ((data_source->uri = strdup(uri)) == NULL)
goto err;
if ((ret = lock_init(session, &data_source->lock)) != 0)
goto err;
ds_lockinit = 1;
/* Read the configuration. */
if ((ret = kvs_config_read(
session, config, &devices, &kvs_config, &flags)) != 0)
goto err;
/* We require a list of devices underlying the URI. */
if (devices[0] == NULL) {
ESET(
session, EINVAL, "WT_SESSION.create: no devices specified");
goto err;
}
/*
* kvs_open isn't re-entrant: lock things down while we make sure we
* don't have more than a single handle at a time.
*/
if ((ret = writelock(session, &global_lock)) != 0)
goto err;
locked = 1;
/*
* Check for a match: if we find one, we raced, but we return success,
* someone else did the work.
*/
for (p = data_source_head; p != NULL; p = p->next)
if (strcmp(p->uri, uri) == 0)
goto err;
/* Open the KVS handle. */
if ((data_source->kvs =
kvs_open(devices, &kvs_config, flags)) == NULL) {
emsg = kvs_create_path_string(devices);
ESET(session, WT_ERROR,
"WT_SESSION.create: kvs_open: %s: %s",
emsg == NULL ? devices[0] : emsg, kvs_strerror(os_errno()));
goto err;
}
/* Insert the new entry at the head of the list. */
data_source->next = data_source_head;
data_source_head = data_source;
data_source = NULL;
err: if (locked)
ETRET(unlock(session, &global_lock));
if (data_source != NULL) {
if (data_source->uri != NULL)
free(data_source->uri);
if (ds_lockinit)
ETRET(lock_destroy(session, &data_source->lock));
free(data_source);
}
free(devices);
free(emsg);
return (ret);
}
