#include "stdafx.h" enum { SQL_EVT_STMT_COUNT = 0, SQL_EVT_STMT_ADDEVENT, SQL_EVT_STMT_DELETE, SQL_EVT_STMT_EDIT, SQL_EVT_STMT_BLOBSIZE, SQL_EVT_STMT_GET, SQL_EVT_STMT_GETFLAGS, SQL_EVT_STMT_SETFLAGS, SQL_EVT_STMT_GETCONTACT, SQL_EVT_STMT_FINDFIRST, SQL_EVT_STMT_FINDFIRSTUNREAD, SQL_EVT_STMT_FINDLAST, SQL_EVT_STMT_GETIDBYSRVID, SQL_EVT_STMT_SETSRVID, SQL_EVT_STMT_ADDEVENT_SRT, SQL_EVT_STMT_DELETE_SRT, SQL_EVT_STMT_META_SPLIT, SQL_EVT_STMT_META_MERGE_SELECT, SQL_EVT_STMT_NUM }; //TODO: hide it inside cursor class static const char* normal_order_query = "select id from events_srt where contact_id = ? order by timestamp;"; static const char* reverse_order_query = "select id from events_srt where contact_id = ? order by timestamp desc, id desc;"; static const char *evt_stmts[SQL_EVT_STMT_NUM] = { "select count(1) from events where contact_id = ? limit 1;", "insert into events(contact_id, module, timestamp, type, flags, data) values (?, ?, ?, ?, ?, ?);", "delete from events where id = ?;", "update events set module = ?, timestamp = ?, type = ?, flags = ?, blob = ? where id = ?;", "select length(data) from events where id = ? limit 1;", "select module, timestamp, type, flags, length(data), data from events where id = ? limit 1;", "select flags from events where id = ? limit 1;", "update events set flags = ? where id = ?;", "select contact_id from events where id = ? limit 1;", normal_order_query, "select id, timestamp from events where contact_id = ? and (flags & ?) = 0 order by timestamp, id limit 1;", reverse_order_query, "select id, timestamp from events where module = ? and server_id = ? limit 1;", "update events set server_id = ? where id = ?;", "insert into events_srt(id, contact_id, timestamp) values (?, ?, ?);", "delete from events_srt where id = ?;", "delete from events_srt where contact_id = ?;", "select id, timestamp from events where contact_id = ?;", }; static sqlite3_stmt *evt_stmts_prep[SQL_EVT_STMT_NUM] = { 0 }; void CDbxSQLite::InitEvents() { for (size_t i = 0; i < SQL_EVT_STMT_NUM; i++) sqlite3_prepare_v3(m_db, evt_stmts[i], -1, SQLITE_PREPARE_PERSISTENT, &evt_stmts_prep[i], nullptr); sqlite3_stmt *stmt = nullptr; sqlite3_prepare_v2(m_db, "select distinct module from events;", -1, &stmt, nullptr); int rc = 0; while ((rc = sqlite3_step(stmt)) == SQLITE_ROW) { const char *module = (char*)sqlite3_column_text(stmt, 0); if (mir_strlen(module) > 0) m_modules.insert(mir_strdup(module)); } assert(rc == SQLITE_ROW || rc == SQLITE_DONE); sqlite3_finalize(stmt); } void CDbxSQLite::UninitEvents() { for (auto module : m_modules.rev_iter()) { m_modules.removeItem(&module); mir_free(module); } for (size_t i = 0; i < SQL_EVT_STMT_NUM; i++) sqlite3_finalize(evt_stmts_prep[i]); } LONG CDbxSQLite::GetEventCount(MCONTACT hContact) { DBCachedContact *cc = (hContact) ? m_cache->GetCachedContact(hContact) : &m_system; if (cc->HasCount()) return cc->m_count; mir_cslock lock(m_csDbAccess); if (cc->IsMeta()) { if (cc->nSubs == 0) { cc->m_count = 0; return 0; } CMStringA query = "select count(1) from events where contact_id in ("; for (int k = 0; k < cc->nSubs; k++) query.AppendFormat("%lu, ", cc->pSubs[k]); query.Delete(query.GetLength() - 2, 2); query.Append(") limit 1;"); sqlite3_stmt *stmt = nullptr; sqlite3_prepare_v2(m_db, query, -1, &stmt, nullptr); int rc = sqlite3_step(stmt); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); if (rc != SQLITE_ROW) { sqlite3_finalize(stmt); return 0; } cc->m_count = sqlite3_column_int64(stmt, 0); sqlite3_finalize(stmt); return cc->m_count; } sqlite3_stmt *stmt = evt_stmts_prep[SQL_EVT_STMT_COUNT]; sqlite3_bind_int64(stmt, 1, hContact); int rc = sqlite3_step(stmt); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); if (rc != SQLITE_ROW) { sqlite3_reset(stmt); return 0; } cc->m_count = sqlite3_column_int64(stmt, 0); sqlite3_reset(stmt); return cc->m_count; } MEVENT CDbxSQLite::AddEvent(MCONTACT hContact, const DBEVENTINFO *dbei) { if (dbei == nullptr) return 0; if (dbei->timestamp == 0) return 0; MCONTACT hNotifyContact = hContact; DBCachedContact *cc, *ccSub = nullptr; if (hContact != 0) { if ((cc = m_cache->GetCachedContact(hContact)) == nullptr) return 0; if (cc->IsSub()) { ccSub = cc; if ((cc = m_cache->GetCachedContact(cc->parentID)) == nullptr) return 0; // set default sub to the event's source if (!(dbei->flags & DBEF_SENT)) db_mc_setDefault(cc->contactID, hContact, false); if (db_mc_isEnabled()) hNotifyContact = cc->contactID; // and add an event to a metahistory } } else cc = &m_system; if (cc == nullptr) return 0; if (m_safetyMode) if (NotifyEventHooks(g_hevEventFiltered, hNotifyContact, (LPARAM)dbei)) return 0; MEVENT hDbEvent = 0; { mir_cslock lock(m_csDbAccess); sqlite3_stmt *stmt = evt_stmts_prep[SQL_EVT_STMT_ADDEVENT]; sqlite3_bind_int64(stmt, 1, hContact); sqlite3_bind_text(stmt, 2, dbei->szModule, (int)mir_strlen(dbei->szModule), nullptr); sqlite3_bind_int64(stmt, 3, dbei->timestamp); sqlite3_bind_int(stmt, 4, dbei->eventType); sqlite3_bind_int64(stmt, 5, dbei->flags); sqlite3_bind_blob(stmt, 6, dbei->pBlob, dbei->cbBlob, nullptr); int rc = sqlite3_step(stmt); assert(rc == SQLITE_DONE); sqlite3_reset(stmt); hDbEvent = sqlite3_last_insert_rowid(m_db); stmt = evt_stmts_prep[SQL_EVT_STMT_ADDEVENT_SRT]; sqlite3_bind_int64(stmt, 1, hDbEvent); sqlite3_bind_int64(stmt, 2, cc->contactID); sqlite3_bind_int64(stmt, 3, dbei->timestamp); rc = sqlite3_step(stmt); assert(rc == SQLITE_DONE); sqlite3_reset(stmt); cc->AddEvent(hDbEvent, dbei->timestamp, !dbei->markedRead()); if (ccSub != nullptr) { stmt = evt_stmts_prep[SQL_EVT_STMT_ADDEVENT_SRT]; sqlite3_bind_int64(stmt, 1, hDbEvent); sqlite3_bind_int64(stmt, 2, ccSub->contactID); sqlite3_bind_int64(stmt, 3, dbei->timestamp); rc = sqlite3_step(stmt); assert(rc == SQLITE_DONE); sqlite3_reset(stmt); //is this necessary ? ccSub->AddEvent(hDbEvent, dbei->timestamp, !dbei->markedRead()); } char *module = m_modules.find(dbei->szModule); if (module == nullptr) m_modules.insert(mir_strdup(dbei->szModule)); } if (m_safetyMode && !(dbei->flags & DBEF_TEMPORARY)) NotifyEventHooks(g_hevEventAdded, hNotifyContact, (LPARAM)hDbEvent); return hDbEvent; } BOOL CDbxSQLite::DeleteEvent(MEVENT hDbEvent) { if (hDbEvent == 0) return 1; MEVENT hContact = GetEventContact(hDbEvent); DBCachedContact *cc = (hContact) ? m_cache->GetCachedContact(hContact) : &m_system; if (cc == nullptr) return 1; { mir_cslock lock(m_csDbAccess); sqlite3_stmt *stmt = evt_stmts_prep[SQL_EVT_STMT_DELETE]; sqlite3_bind_int64(stmt, 1, hDbEvent); int rc = sqlite3_step(stmt); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); sqlite3_reset(stmt); if (rc != SQLITE_DONE) return 1; stmt = evt_stmts_prep[SQL_EVT_STMT_DELETE_SRT]; sqlite3_bind_int64(stmt, 1, hDbEvent); rc = sqlite3_step(stmt); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); sqlite3_reset(stmt); if (rc != SQLITE_DONE) return 1; cc->DeleteEvent(hDbEvent); if (cc->IsSub() && (cc = m_cache->GetCachedContact(cc->parentID))) cc->DeleteEvent(hDbEvent); } NotifyEventHooks(g_hevEventDeleted, hContact, hDbEvent); return 0; } BOOL CDbxSQLite::EditEvent(MCONTACT hContact, MEVENT hDbEvent, const DBEVENTINFO *dbei) { if (dbei == nullptr) return 1; if (dbei->timestamp == 0) return 1; DBCachedContact *cc = (hContact) ? m_cache->GetCachedContact(hContact) : &m_system; if (cc == nullptr) return 1; { mir_cslock lock(m_csDbAccess); sqlite3_stmt *stmt = evt_stmts_prep[SQL_EVT_STMT_EDIT]; sqlite3_bind_text(stmt, 1, dbei->szModule, (int)mir_strlen(dbei->szModule), nullptr); sqlite3_bind_int64(stmt, 2, dbei->timestamp); sqlite3_bind_int(stmt, 3, dbei->eventType); sqlite3_bind_int64(stmt, 4, dbei->flags); sqlite3_bind_blob(stmt, 5, dbei->pBlob, dbei->cbBlob, nullptr); sqlite3_bind_int64(stmt, 6, hDbEvent); int rc = sqlite3_step(stmt); assert(rc == SQLITE_DONE); sqlite3_reset(stmt); cc->EditEvent(hDbEvent, dbei->timestamp, !dbei->markedRead()); if (cc->IsSub() && (cc = m_cache->GetCachedContact(cc->parentID))) cc->EditEvent(hDbEvent, dbei->timestamp, !dbei->markedRead()); char *module = m_modules.find(dbei->szModule); if (module == nullptr) m_modules.insert(mir_strdup(dbei->szModule)); } NotifyEventHooks(g_hevEventEdited, hContact, (LPARAM)hDbEvent); return 0; } LONG CDbxSQLite::GetBlobSize(MEVENT hDbEvent) { if (hDbEvent == 0) return -1; mir_cslock lock(m_csDbAccess); sqlite3_stmt *stmt = evt_stmts_prep[SQL_EVT_STMT_BLOBSIZE]; sqlite3_bind_int(stmt, 1, hDbEvent); int rc = sqlite3_step(stmt); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); if (rc != SQLITE_ROW) { sqlite3_reset(stmt); return -1; } LONG res = sqlite3_column_int64(stmt, 0); sqlite3_reset(stmt); return res; } BOOL CDbxSQLite::GetEvent(MEVENT hDbEvent, DBEVENTINFO *dbei) { if (hDbEvent == 0) return 1; if (dbei == nullptr) return 1; if (dbei->cbBlob > 0 && dbei->pBlob == nullptr) { dbei->cbBlob = 0; return 1; } mir_cslock lock(m_csDbAccess); sqlite3_stmt *stmt = evt_stmts_prep[SQL_EVT_STMT_GET]; sqlite3_bind_int64(stmt, 1, hDbEvent); int rc = sqlite3_step(stmt); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); if (rc != SQLITE_ROW) { sqlite3_reset(stmt); return 1; } char *module = (char*)sqlite3_column_text(stmt, 0); dbei->szModule = m_modules.find(module); if (dbei->szModule == nullptr) return 1; dbei->timestamp = sqlite3_column_int64(stmt, 1); dbei->eventType = sqlite3_column_int(stmt, 2); dbei->flags = sqlite3_column_int64(stmt, 3); DWORD cbBlob = sqlite3_column_int64(stmt, 4); int bytesToCopy = (dbei->cbBlob < cbBlob) ? dbei->cbBlob : cbBlob; dbei->cbBlob = cbBlob; if (bytesToCopy && dbei->pBlob) { BYTE *data = (BYTE*)sqlite3_column_blob(stmt, 5); memcpy(dbei->pBlob, data, bytesToCopy); } sqlite3_reset(stmt); return 0; } BOOL CDbxSQLite::MarkEventRead(MCONTACT hContact, MEVENT hDbEvent) { if (hDbEvent == 0) return -1; DBCachedContact *cc = (hContact) ? m_cache->GetCachedContact(hContact) : &m_system; if (cc == nullptr) return -1; DWORD flags = 0; { mir_cslock lock(m_csDbAccess); sqlite3_stmt *stmt = evt_stmts_prep[SQL_EVT_STMT_GETFLAGS]; sqlite3_bind_int64(stmt, 1, hDbEvent); int rc = sqlite3_step(stmt); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); if (rc != SQLITE_ROW) { sqlite3_reset(stmt); return -1; } flags = sqlite3_column_int64(stmt, 0); sqlite3_reset(stmt); } if ((flags & DBEF_READ) == DBEF_READ) return flags; flags |= DBEF_READ; { mir_cslock lock(m_csDbAccess); sqlite3_stmt *stmt = evt_stmts_prep[SQL_EVT_STMT_SETFLAGS]; sqlite3_bind_int(stmt, 1, flags); sqlite3_bind_int64(stmt, 2, hDbEvent); int rc = sqlite3_step(stmt); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); sqlite3_reset(stmt); if (rc != SQLITE_DONE) return -1; cc->MarkRead(hDbEvent); if (cc->IsSub() && (cc = m_cache->GetCachedContact(cc->parentID))) cc->MarkRead(hDbEvent); } NotifyEventHooks(g_hevMarkedRead, hContact, (LPARAM)hDbEvent); return flags; } MCONTACT CDbxSQLite::GetEventContact(MEVENT hDbEvent) { if (hDbEvent == 0) return INVALID_CONTACT_ID; mir_cslock lock(m_csDbAccess); sqlite3_stmt *stmt = evt_stmts_prep[SQL_EVT_STMT_GETCONTACT]; sqlite3_bind_int64(stmt, 1, hDbEvent); int rc = sqlite3_step(stmt); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); if (rc != SQLITE_ROW) { sqlite3_reset(stmt); return INVALID_CONTACT_ID; } MCONTACT hContact = sqlite3_column_int64(stmt, 0); sqlite3_reset(stmt); return hContact; } MEVENT CDbxSQLite::FindFirstEvent(MCONTACT hContact) { DBCachedContact *cc = (hContact) ? m_cache->GetCachedContact(hContact) : &m_system; if (cc == nullptr) return 0; evt_cnt_fwd = hContact; mir_cslock lock(m_csDbAccess); if (evt_cur_fwd) { sqlite3_reset(evt_cur_fwd); } evt_cur_fwd = evt_stmts_prep[SQL_EVT_STMT_FINDFIRST]; sqlite3_bind_int64(evt_cur_fwd, 1, hContact); int rc = sqlite3_step(evt_cur_fwd); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); if (rc != SQLITE_ROW) { //empty response //reset sql cursor sqlite3_reset(evt_cur_fwd); evt_cur_fwd = 0; //reset current contact evt_cnt_fwd = 0; return 0; } return sqlite3_column_int64(evt_cur_fwd, 0); } MEVENT CDbxSQLite::FindFirstUnreadEvent(MCONTACT hContact) { DBCachedContact *cc = (hContact) ? m_cache->GetCachedContact(hContact) : &m_system; if (cc == nullptr) return 0; if (cc->m_unread) return cc->m_unread; mir_cslock lock(m_csDbAccess); if (cc->IsMeta()) { if (cc->nSubs == 0) { cc->m_unread = 0; cc->m_unreadTimestamp = 0; return 0; } CMStringA query(FORMAT, "select id from events where (flags & %d) = 0 and contact_id in (", DBEF_READ | DBEF_SENT); for (int k = 0; k < cc->nSubs; k++) query.AppendFormat("%lu, ", cc->pSubs[k]); query.Delete(query.GetLength() - 2, 2); query.Append(") order by timestamp, id limit 1;"); sqlite3_stmt *stmt; sqlite3_prepare_v2(m_db, query, -1, &stmt, nullptr); int rc = sqlite3_step(stmt); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); if (rc != SQLITE_ROW) { sqlite3_finalize(stmt); return 0; } cc->m_unread = sqlite3_column_int64(stmt, 0); cc->m_unreadTimestamp = sqlite3_column_int64(stmt, 1); sqlite3_finalize(stmt); return cc->m_unread; } sqlite3_stmt *stmt = evt_stmts_prep[SQL_EVT_STMT_FINDFIRSTUNREAD]; sqlite3_bind_int64(stmt, 1, hContact); sqlite3_bind_int(stmt, 2, DBEF_READ | DBEF_SENT); int rc = sqlite3_step(stmt); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); if (rc != SQLITE_ROW) { sqlite3_reset(stmt); return 0; } cc->m_unread = sqlite3_column_int64(stmt, 0); cc->m_unreadTimestamp = sqlite3_column_int64(stmt, 1); sqlite3_reset(stmt); return cc->m_unread; } MEVENT CDbxSQLite::FindLastEvent(MCONTACT hContact) { DBCachedContact *cc = (hContact) ? m_cache->GetCachedContact(hContact) : &m_system; if (cc == nullptr) return 0; evt_cnt_backwd = hContact; mir_cslock lock(m_csDbAccess); if (evt_cur_backwd) { sqlite3_reset(evt_cur_backwd); } evt_cur_backwd = evt_stmts_prep[SQL_EVT_STMT_FINDLAST]; sqlite3_bind_int64(evt_cur_backwd, 1, hContact); int rc = sqlite3_step(evt_cur_backwd); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); if (rc != SQLITE_ROW) { //empty response //reset sql cursor sqlite3_reset(evt_cur_backwd); evt_cur_backwd = 0; //reset current contact evt_cnt_backwd = 0; return 0; } return sqlite3_column_int64(evt_cur_backwd, 0); } MEVENT CDbxSQLite::FindNextEvent(MCONTACT hContact, MEVENT hDbEvent) { if (hDbEvent == 0) return 0; DBCachedContact *cc = m_cache->GetCachedContact(hContact); if (cc == nullptr) return 0; if (!evt_cur_fwd) { return 0; } if (hContact != evt_cnt_fwd) { return 0; } while (hDbEvent != sqlite3_column_int64(evt_cur_fwd, 0)) { int rc = sqlite3_step(evt_cur_fwd); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); if (rc == SQLITE_DONE) { //reset sql cursor sqlite3_reset(evt_cur_fwd); evt_cur_fwd = 0; //reset current contact evt_cnt_fwd = 0; return 0; } } int rc = sqlite3_step(evt_cur_fwd); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); if (rc != SQLITE_ROW) { //reset sql cursor sqlite3_reset(evt_cur_fwd); evt_cur_fwd = 0; //reset current contact evt_cnt_fwd = 0; return 0; } hDbEvent = sqlite3_column_int64(evt_cur_fwd, 0); return hDbEvent; } MEVENT CDbxSQLite::FindPrevEvent(MCONTACT hContact, MEVENT hDbEvent) { if (hDbEvent == 0) return 0; DBCachedContact *cc = m_cache->GetCachedContact(hContact); if (cc == nullptr) return 0; if (!evt_cur_backwd) { return 0; } if (hContact != evt_cnt_backwd) { return 0; } while (hDbEvent != sqlite3_column_int64(evt_cur_backwd, 0)) { int rc = sqlite3_step(evt_cur_backwd); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); if (rc == SQLITE_DONE) { //reset sql cursor sqlite3_reset(evt_cur_backwd); evt_cur_backwd = 0; //reset current contact evt_cnt_backwd = 0; return 0; } } int rc = sqlite3_step(evt_cur_backwd); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); if (rc != SQLITE_ROW) { //reset sql cursor sqlite3_reset(evt_cur_backwd); evt_cur_backwd = 0; //reset current contact evt_cnt_backwd = 0; return 0; } hDbEvent = sqlite3_column_int64(evt_cur_backwd, 0); return hDbEvent; } MEVENT CDbxSQLite::GetEventById(LPCSTR szModule, LPCSTR szId) { if (szModule == nullptr || szId == nullptr) return 0; mir_cslock lock(m_csDbAccess); sqlite3_stmt *stmt = evt_stmts_prep[SQL_EVT_STMT_GETIDBYSRVID]; sqlite3_bind_text(stmt, 1, szModule, (int)mir_strlen(szModule), nullptr); sqlite3_bind_text(stmt, 2, szId, (int)mir_strlen(szId), nullptr); int rc = sqlite3_step(stmt); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); if (rc != SQLITE_ROW) { sqlite3_reset(stmt); return 0; } MEVENT hDbEvent = sqlite3_column_int64(stmt, 0); sqlite3_reset(stmt); return hDbEvent; } BOOL CDbxSQLite::SetEventId(LPCSTR, MEVENT hDbEvent, LPCSTR szId) { if (hDbEvent == 0 || szId == nullptr) return 1; mir_cslock lock(m_csDbAccess); sqlite3_stmt *stmt = evt_stmts_prep[SQL_EVT_STMT_SETSRVID]; sqlite3_bind_text(stmt, 1, szId, (int)mir_strlen(szId), nullptr); sqlite3_bind_int64(stmt, 2, hDbEvent); int rc = sqlite3_step(stmt); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); sqlite3_reset(stmt); return (rc != SQLITE_DONE); } BOOL CDbxSQLite::MetaMergeHistory(DBCachedContact *ccMeta, DBCachedContact *ccSub) { //TODO: test this mir_cslock lock(m_csDbAccess); sqlite3_stmt *stmt = evt_stmts_prep[SQL_EVT_STMT_META_MERGE_SELECT]; sqlite3_bind_int64(stmt, 1, ccSub->contactID); int rc = sqlite3_step(stmt); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); while (rc == SQLITE_ROW) { sqlite3_stmt *stmt2 = evt_stmts_prep[SQL_EVT_STMT_ADDEVENT_SRT]; sqlite3_bind_int64(stmt2, 1, sqlite3_column_int64(stmt, 0)); sqlite3_bind_int64(stmt2, 2, ccMeta->contactID); sqlite3_bind_int64(stmt2, 3, sqlite3_column_int64(stmt, 1)); int rc2 = sqlite3_step(stmt2); assert(rc2 == SQLITE_ROW || rc == SQLITE_DONE); sqlite3_reset(stmt2); rc = sqlite3_step(stmt); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); } sqlite3_reset(stmt); return TRUE; } BOOL CDbxSQLite::MetaSplitHistory(DBCachedContact *ccMeta, DBCachedContact*) { mir_cslock lock(m_csDbAccess); sqlite3_stmt *stmt = evt_stmts_prep[SQL_EVT_STMT_META_SPLIT]; sqlite3_bind_int64(stmt, 1, ccMeta->contactID); int rc = sqlite3_step(stmt); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); sqlite3_reset(stmt); if (rc != SQLITE_DONE) return 1; return TRUE; } STDMETHODIMP_(DB::EventCursor*) CDbxSQLite::EventCursor(MCONTACT hContact, DBEVENTINFO& dbei) { return new CDbxSQLiteEventCursor(hContact, dbei, m_db); } STDMETHODIMP_(DB::EventCursor*) CDbxSQLite::EventCursorRev(MCONTACT hContact, DBEVENTINFO& dbei) { return new CDbxSQLiteEventCursor(hContact, dbei, m_db, true); } CDbxSQLiteEventCursor::CDbxSQLiteEventCursor(MCONTACT _1, DBEVENTINFO& _2, sqlite3* _db, bool reverse) : EventCursorBase(_1, _2), m_db(_db) { if (reverse) sqlite3_prepare_v2(m_db, reverse_order_query, -1, &cursor, nullptr); else sqlite3_prepare_v2(m_db, normal_order_query, -1, &cursor, nullptr); sqlite3_bind_int64(cursor, 1, hContact); } CDbxSQLiteEventCursor::~CDbxSQLiteEventCursor() { if (cursor) sqlite3_reset(cursor); } MEVENT CDbxSQLiteEventCursor::FetchNext() { if (!cursor) return 0; int rc = sqlite3_step(cursor); assert(rc == SQLITE_ROW || rc == SQLITE_DONE); if (rc != SQLITE_ROW) { //empty response //reset sql cursor sqlite3_reset(cursor); cursor = nullptr; return 0; } return sqlite3_column_int64(cursor, 0); }