/* * __curmetadata_search_near -- * WT_CURSOR->search_near method for the metadata cursor type. */ static int __curmetadata_search_near(WT_CURSOR *cursor, int *exact) { WT_CURSOR *file_cursor; WT_CURSOR_METADATA *mdc; WT_DECL_RET; WT_SESSION_IMPL *session; mdc = (WT_CURSOR_METADATA *)cursor; file_cursor = mdc->file_cursor; CURSOR_API_CALL(cursor, session, search_near, ((WT_CURSOR_BTREE *)file_cursor)->btree); WT_MD_CURSOR_NEEDKEY(cursor); if (WT_KEY_IS_METADATA(&cursor->key)) { WT_ERR(__curmetadata_metadata_search(session, cursor)); *exact = 1; } else { WT_WITH_TXN_ISOLATION(session, WT_ISO_READ_UNCOMMITTED, ret = file_cursor->search_near(file_cursor, exact)); WT_ERR(ret); WT_ERR(__curmetadata_setkv(mdc, file_cursor)); } err: if (ret != 0) { F_CLR(mdc, WT_MDC_POSITIONED | WT_MDC_ONMETADATA); F_CLR(cursor, WT_CURSTD_KEY_EXT | WT_CURSTD_VALUE_EXT); } API_END_RET(session, ret); }
/* * __curmetadata_prev -- * WT_CURSOR->prev method for the metadata cursor type. */ static int __curmetadata_prev(WT_CURSOR *cursor) { WT_CURSOR *file_cursor; WT_CURSOR_METADATA *mdc; WT_DECL_RET; WT_SESSION_IMPL *session; mdc = (WT_CURSOR_METADATA *)cursor; file_cursor = mdc->file_cursor; CURSOR_API_CALL(cursor, session, prev, ((WT_CURSOR_BTREE *)file_cursor)->btree); if (F_ISSET(mdc, WT_MDC_ONMETADATA)) { ret = WT_NOTFOUND; goto err; } WT_WITH_TXN_ISOLATION(session, WT_ISO_READ_UNCOMMITTED, ret = file_cursor->prev(file_cursor)); if (ret == 0) WT_ERR(__curmetadata_setkv(mdc, file_cursor)); else if (ret == WT_NOTFOUND) WT_ERR(__curmetadata_metadata_search(session, cursor)); err: if (ret != 0) { F_CLR(mdc, WT_MDC_POSITIONED | WT_MDC_ONMETADATA); F_CLR(cursor, WT_CURSTD_KEY_EXT | WT_CURSTD_VALUE_EXT); } API_END_RET(session, ret); }
/* * __curmetadata_next -- * WT_CURSOR->next method for the metadata cursor type. */ static int __curmetadata_next(WT_CURSOR *cursor) { WT_CURSOR *file_cursor; WT_CURSOR_METADATA *mdc; WT_DECL_RET; WT_SESSION_IMPL *session; mdc = (WT_CURSOR_METADATA *)cursor; file_cursor = mdc->file_cursor; CURSOR_API_CALL(cursor, session, next, ((WT_CURSOR_BTREE *)file_cursor)->btree); if (!F_ISSET(mdc, WT_MDC_POSITIONED)) WT_ERR(__curmetadata_metadata_search(session, cursor)); else { /* * When applications open metadata cursors, they expect to see * all schema-level operations reflected in the results. Query * at read-uncommitted to avoid confusion caused by the current * transaction state. */ WT_WITH_TXN_ISOLATION(session, WT_ISO_READ_UNCOMMITTED, ret = file_cursor->next(mdc->file_cursor)); WT_ERR(ret); WT_ERR(__curmetadata_setkv(mdc, file_cursor)); } err: if (ret != 0) { F_CLR(mdc, WT_MDC_POSITIONED | WT_MDC_ONMETADATA); F_CLR(cursor, WT_CURSTD_KEY_EXT | WT_CURSTD_VALUE_EXT); } API_END_RET(session, ret); }
/* * __wt_schema_open_index -- * Open one or more indices for a table. */ int __wt_schema_open_index(WT_SESSION_IMPL *session, WT_TABLE *table, const char *idxname, size_t len, WT_INDEX **indexp) { WT_DECL_RET; WT_WITH_TXN_ISOLATION(session, WT_ISO_READ_UNCOMMITTED, ret = __schema_open_index(session, table, idxname, len, indexp)); return (ret); }
/* * __wt_schema_open_table -- * Open a named table. */ int __wt_schema_open_table(WT_SESSION_IMPL *session, const char *name, size_t namelen, bool ok_incomplete, WT_TABLE **tablep) { WT_DECL_RET; WT_WITH_TXN_ISOLATION(session, WT_ISO_READ_UNCOMMITTED, ret = __schema_open_table( session, name, namelen, ok_incomplete, tablep)); return (ret); }
/* * __wt_metadata_search -- * Return a copied row from the metadata. * The caller is responsible for freeing the allocated memory. */ int __wt_metadata_search(WT_SESSION_IMPL *session, const char *key, char **valuep) { WT_CURSOR *cursor; WT_DECL_RET; const char *value; *valuep = NULL; __wt_verbose(session, WT_VERB_METADATA, "Search: key: %s, tracking: %s, %s" "turtle", key, WT_META_TRACKING(session) ? "true" : "false", __metadata_turtle(key) ? "" : "not "); if (__metadata_turtle(key)) { /* * The returned value should only be set if ret is non-zero, but * Coverity is convinced otherwise. The code path is used enough * that Coverity complains a lot, add an error check to get some * peace and quiet. */ if ((ret = __wt_turtle_read(session, key, valuep)) != 0) __wt_free(session, *valuep); return (ret); } /* * All metadata reads are at read-uncommitted isolation. That's * because once a schema-level operation completes, subsequent * operations must see the current version of checkpoint metadata, or * they may try to read blocks that may have been freed from a file. * Metadata updates use non-transactional techniques (such as the * schema and metadata locks) to protect access to in-flight updates. */ WT_RET(__wt_metadata_cursor(session, &cursor)); cursor->set_key(cursor, key); WT_WITH_TXN_ISOLATION(session, WT_ISO_READ_UNCOMMITTED, ret = cursor->search(cursor)); WT_ERR(ret); WT_ERR(cursor->get_value(cursor, &value)); WT_ERR(__wt_strdup(session, value, valuep)); err: WT_TRET(__wt_metadata_cursor_release(session, &cursor)); if (ret != 0) __wt_free(session, *valuep); return (ret); }
/* * __wt_metadata_search -- * Return a copied row from the metadata. * The caller is responsible for freeing the allocated memory. */ int __wt_metadata_search(WT_SESSION_IMPL *session, const char *key, char **valuep) { WT_CURSOR *cursor; WT_DECL_RET; const char *value; *valuep = NULL; WT_RET(__wt_verbose(session, WT_VERB_METADATA, "Search: key: %s, tracking: %s, %s" "turtle", key, WT_META_TRACKING(session) ? "true" : "false", __metadata_turtle(key) ? "" : "not ")); if (__metadata_turtle(key)) return (__wt_turtle_read(session, key, valuep)); /* * All metadata reads are at read-uncommitted isolation. That's * because once a schema-level operation completes, subsequent * operations must see the current version of checkpoint metadata, or * they may try to read blocks that may have been freed from a file. * Metadata updates use non-transactional techniques (such as the * schema and metadata locks) to protect access to in-flight updates. */ WT_RET(__wt_metadata_cursor(session, &cursor)); cursor->set_key(cursor, key); WT_WITH_TXN_ISOLATION(session, WT_ISO_READ_UNCOMMITTED, ret = cursor->search(cursor)); WT_ERR(ret); WT_ERR(cursor->get_value(cursor, &value)); WT_ERR(__wt_strdup(session, value, valuep)); err: WT_TRET(__wt_metadata_cursor_release(session, &cursor)); return (ret); }