freepascal.compiler/fcl/db/sqldb/mysql/mysql4conn.pas

unit mysql4conn;

{$mode objfpc}{$H+}

{$Define LinkDynamically}

interface

uses
  Classes, SysUtils,sqldb,db,
{$IfDef LinkDynamically}
  mysql4dyn,mysql4_comdyn;
{$Else}
  mysql4,mysql4_com;
{$EndIf}

Type
  TMySQLTransaction = Class(TSQLHandle)
  protected
  end;

  TMySQLCursor = Class(TSQLHandle)
  protected
    FQMySQL : PMySQL;
    FRes: PMYSQL_RES;                   { Record pointer }
    FNeedData : Boolean;
    FStatement : String;
    Row : TMYSQL_ROW;
    RowsAffected : Int64;
    LastInsertID : Int64;
  end;

  TMySQLConnection = class (TSQLConnection)
  private
    FDialect: integer;
    FHostInfo: String;
    FServerInfo: String;
    FMySQL : PMySQL;
    function GetClientInfo: string;
    function GetServerStatus: String;
    procedure ConnectMySQL(var HMySQL : PMySQL;H,U,P : pchar);
  protected
    function StrToStatementType(s : string) : TStatementType; override;
    Procedure ConnectToServer; virtual;
    Procedure SelectDatabase; virtual;
    function MySQLDataType(AType: enum_field_types; ASize: Integer; var NewType: TFieldType; var NewSize: Integer): Boolean;
    function MySQLWriteData(AType: enum_field_types; ASize: Integer; Source, Dest: PChar): Integer;
    // SQLConnection methods
    procedure DoInternalConnect; override;
    procedure DoInternalDisconnect; override;
    function GetHandle : pointer; override;

    Function AllocateCursorHandle : TSQLHandle; override;
    Function AllocateTransactionHandle : TSQLHandle; override;

    procedure FreeStatement(cursor : TSQLHandle); override;
    procedure PrepareStatement(cursor: TSQLHandle;ATransaction : TSQLTransaction;buf : string); override;
    procedure FreeFldBuffers(cursor : TSQLHandle); override;
    procedure Execute(cursor: TSQLHandle;atransaction:tSQLtransaction); override;
    procedure AddFieldDefs(cursor: TSQLHandle; FieldDefs : TfieldDefs); override;
    function Fetch(cursor : TSQLHandle) : boolean; override;
    function LoadField(cursor : TSQLHandle;FieldDef : TfieldDef;buffer : pointer) : boolean; override;
    function GetTransactionHandle(trans : TSQLHandle): pointer; override;
    function Commit(trans : TSQLHandle) : boolean; override;
    function RollBack(trans : TSQLHandle) : boolean; override;
    function StartdbTransaction(trans : TSQLHandle) : boolean; override;
    procedure CommitRetaining(trans : TSQLHandle); override;
    procedure RollBackRetaining(trans : TSQLHandle); override;
    procedure UpdateIndexDefs(var IndexDefs : TIndexDefs;TableName : string); override;

  Public
    Property ServerInfo : String Read FServerInfo;
    Property HostInfo : String Read FHostInfo;
    property ClientInfo: string read GetClientInfo;
    property ServerStatus : String read GetServerStatus;
  published
    property Dialect  : integer read FDialect write FDialect;
    property DatabaseName;
    property HostName;
    property KeepConnection;
    property LoginPrompt;
    property Params;
    property OnLogin;
  end;

  EMySQLError = Class(Exception);

implementation

uses dbconst;

{ TMySQLConnection }

Resourcestring
  SErrServerConnectFailed = 'Server connect failed.';
  SErrDatabaseSelectFailed = 'failed to select database: %s';
  SErrDatabaseCreate = 'Failed to create database: %s';
  SErrDatabaseDrop = 'Failed to drop database: %s';
  SErrNoData = 'No data for record';
  SErrExecuting = 'Error executing query: %s';
  SErrFetchingdata = 'Error fetching row data: %s';
  SErrGettingResult = 'Error getting result set: %s';
  SErrNoQueryResult = 'No result from query.';
  
Procedure MySQlError(R : PMySQL;Msg: String;Comp : TComponent);

Var
  MySQLMsg : String;

begin
 If (R<>Nil) then
   begin
   MySQLMsg:=Strpas(mysql_error(R));
   DatabaseErrorFmt(Msg,[MySQLMsg],Comp);
   end
 else
   DatabaseError(Msg,Comp);
end;

function TMySQLConnection.StrToStatementType(s : string) : TStatementType;

begin
  S:=Lowercase(s);
  if s = 'show' then exit(stSelect);
  result := inherited StrToStatementType(s);
end;


function TMySQLConnection.GetClientInfo: string;

begin
{$IfDef LinkDynamically}
  // To make it possible to call this if there's no connection yet
  InitialiseMysql4;
{$EndIf}
  Result:=strpas(mysql_get_client_info());
{$IfDef LinkDynamically}
  ReleaseMysql4;
{$EndIf}

end;

function TMySQLConnection.GetServerStatus: String;
begin
  CheckConnected;
  Result := mysql_stat(FMYSQL);
end;

procedure TMySQLConnection.ConnectMySQL(var HMySQL : PMySQL;H,U,P : pchar);

begin
  if (HMySQL=Nil) then
    New(HMySQL);
  mysql_init(HMySQL);
  HMySQL:=mysql_real_connect(HMySQL,PChar(H),PChar(U),Pchar(P),Nil,0,Nil,0);
  If (HMySQL=Nil) then
    MySQlError(Nil,SErrServerConnectFailed,Self);
end;

procedure TMySQLConnection.ConnectToServer;

Var
  H,U,P : String;

begin
  H:=HostName;
  U:=UserName;
  P:=Password;
  ConnectMySQL(FMySQL,pchar(H),pchar(U),pchar(P));
  FServerInfo := strpas(mysql_get_server_info(FMYSQL));
  FHostInfo := strpas(mysql_get_host_info(FMYSQL));
end;

procedure TMySQLConnection.SelectDatabase;
begin
  if mysql_select_db(FMySQL,pchar(DatabaseName))<>0 then
    MySQLError(FMySQL,SErrDatabaseSelectFailed,Self);
end;

procedure TMySQLConnection.DoInternalConnect;
begin
{$IfDef LinkDynamically}
  InitialiseMysql4;
{$EndIf}
  inherited DoInternalConnect;
  ConnectToServer;
  SelectDatabase;
end;

procedure TMySQLConnection.DoInternalDisconnect;
begin
  inherited DoInternalDisconnect;
  mysql_close(FMySQL);
  FMySQL:=Nil;
{$IfDef LinkDynamically}
  ReleaseMysql4;
{$EndIf}

end;

function TMySQLConnection.GetHandle: pointer;
begin
  Result:=FMySQL;
end;

function TMySQLConnection.AllocateCursorHandle: TSQLHandle;
begin
  Result:=TMySQLCursor.Create;
end;

function TMySQLConnection.AllocateTransactionHandle: TSQLHandle;
begin
  Result:=TMySQLTransaction.Create;
end;

procedure TMySQLConnection.FreeStatement(cursor: TSQLHandle);

Var
  C : TMySQLCursor;

begin
  C:=Cursor as TMysqlCursor;
  if c.StatementType=stSelect then
    c.FNeedData:=False;
  If (C.FRes<>Nil) then
    begin
    C.FRes:=Nil;
    end;
  if (c.FQMySQL <> Nil) then
    begin
    mysql_close(c.FQMySQL);
    c.FQMySQL:=Nil;
    end;
end;

procedure TMySQLConnection.PrepareStatement(cursor: TSQLHandle;
  ATransaction: TSQLTransaction; buf: string);
begin
  With Cursor as TMysqlCursor do
    begin
    FStatement:=Buf;
    if StatementType=stSelect then
      FNeedData:=True;
    ConnectMySQL(FQMySQL,FMySQL^.host,FMySQL^.user,FMySQL^.passwd);
    if mysql_select_db(FQMySQL,pchar(DatabaseName))<>0 then
      MySQLError(FQMySQL,SErrDatabaseSelectFailed,Self);
    end
end;

procedure TMySQLConnection.FreeFldBuffers(cursor: TSQLHandle);

Var
  C : TMySQLCursor;
  
begin
  C:=Cursor as TMysqlCursor;
  If (C.FRes<>Nil) then
    begin
    Mysql_free_result(C.FRes);
    C.FRes:=Nil;
    end;
end;

procedure TMySQLConnection.Execute(cursor: TSQLHandle;
  atransaction: tSQLtransaction);
  
Var
  C : TMySQLCursor;

begin
  C:=Cursor as TMysqlCursor;
  If (C.FRes=Nil) then
    begin
    if mysql_query(c.FQMySQL,Pchar(C.FStatement))<>0 then
      MySQLError(c.FQMYSQL,Format(SErrExecuting,[StrPas(mysql_error(c.FQMySQL))]),Self)
    else
      begin
      C.RowsAffected := mysql_affected_rows(c.FQMYSQL);
      C.LastInsertID := mysql_insert_id(c.FQMYSQL);
      if C.FNeedData then
        C.FRes:=mysql_use_result(c.FQMySQL);
      end;
    end;
end;

function TMySQLConnection.MySQLDataType(AType: enum_field_types; ASize: Integer;
   var NewType: TFieldType; var NewSize: Integer): Boolean;
begin
  Result := True;
  case AType of
    FIELD_TYPE_TINY, FIELD_TYPE_SHORT, FIELD_TYPE_LONG, FIELD_TYPE_LONGLONG,
    FIELD_TYPE_INT24:
      begin
      NewType := ftInteger;
      NewSize := 0;
      end;
    FIELD_TYPE_DECIMAL, FIELD_TYPE_FLOAT, FIELD_TYPE_DOUBLE:
      begin
      NewType := ftFloat;
      NewSize := 0;
      end;
    FIELD_TYPE_TIMESTAMP, FIELD_TYPE_DATETIME:
      begin
      NewType := ftDateTime;
      NewSize := 0;
      end;
    FIELD_TYPE_DATE:
      begin
      NewType := ftDate;
      NewSize := 0;
      end;
    FIELD_TYPE_TIME:
      begin
      NewType := ftTime;
      NewSize := 0;
      end;
    FIELD_TYPE_VAR_STRING, FIELD_TYPE_STRING, FIELD_TYPE_ENUM, FIELD_TYPE_SET:
      begin
      NewType := ftString;
      NewSize := ASize;
      end;
  else
    Result := False;
  end;
end;

procedure TMySQLConnection.AddFieldDefs(cursor: TSQLHandle;
  FieldDefs: TfieldDefs);
  
var
  C : TMySQLCursor;
  I, FC: Integer;
  field: PMYSQL_FIELD;
  DFT: TFieldType;
  DFS: Integer;

begin
//  Writeln('MySQL: Adding fielddefs');
  C:=(Cursor as TMySQLCursor);
  If (C.FRes=Nil) then
    begin
//    Writeln('res is nil');
    MySQLError(c.FQMySQL,SErrNoQueryResult,Self);
    end;
//  Writeln('MySQL: have result');
  FC:=mysql_num_fields(C.FRes);
  For I:= 0 to FC-1 do
    begin
    field := mysql_fetch_field_direct(C.FRES, I);
//    Writeln('MySQL: creating fielddef ',I+1);

    if MySQLDataType(field^.ftype, field^.length, DFT, DFS) then
      TFieldDef.Create(FieldDefs, field^.name, DFT, DFS, False, I+1);
    end;
//  Writeln('MySQL: Finished adding fielddefs');
end;

function TMySQLConnection.Fetch(cursor: TSQLHandle): boolean;

Var
  C : TMySQLCursor;

begin
  C:=Cursor as TMySQLCursor;
  C.Row:=MySQL_Fetch_row(C.FRes);
  Result:=(C.Row<>Nil);
end;

function TMySQLConnection.LoadField(cursor : TSQLHandle;
  FieldDef : TfieldDef;buffer : pointer) : boolean;

var
  I, FC, CT: Integer;
  field: PMYSQL_FIELD;
  row : TMYSQL_ROW;
  C : TMySQLCursor;

begin
//  Writeln('LoadFieldsFromBuffer');
  C:=Cursor as TMySQLCursor;
  if C.Row=nil then
     begin
  //   Writeln('LoadFieldsFromBuffer: row=nil');
     MySQLError(c.FQMySQL,SErrFetchingData,Self);
     end;
  Row:=C.Row;
  FC := mysql_num_fields(C.FRES);

  for I := 0 to FC-1 do
    begin
    field := mysql_fetch_field_direct(C.FRES, I);
    if field^.name=FieldDef.name then break;
    Inc(Row);
    end;

  CT := MySQLWriteData(field^.ftype, field^.length, Row^, Buffer);
  result := true;
end;

function InternalStrToFloat(S: string): Extended;

var
  I: Integer;
  Tmp: string;

begin
  Tmp := '';
  for I := 1 to Length(S) do
    begin
    if not (S[I] in ['0'..'9', '+', '-', 'E', 'e']) then
      Tmp := Tmp + DecimalSeparator
    else
      Tmp := Tmp + S[I];
    end;
  Result := StrToFloat(Tmp);
end;

function InternalStrToDate(S: string): TDateTime;

var
  EY, EM, ED: Word;

begin
  EY := StrToInt(Copy(S,1,4));
  EM := StrToInt(Copy(S,6,2));
  ED := StrToInt(Copy(S,9,2));
  if (EY = 0) or (EM = 0) or (ED = 0) then
    Result:=0
  else
    Result:=EncodeDate(EY, EM, ED);
end;

function InternalStrToDateTime(S: string): TDateTime;

var
  EY, EM, ED: Word;
  EH, EN, ES: Word;

begin
  EY := StrToInt(Copy(S, 1, 4));
  EM := StrToInt(Copy(S, 6, 2));
  ED := StrToInt(Copy(S, 9, 2));
  EH := StrToInt(Copy(S, 11, 2));
  EN := StrToInt(Copy(S, 14, 2));
  ES := StrToInt(Copy(S, 17, 2));
  if (EY = 0) or (EM = 0) or (ED = 0) then
    Result := 0
  else
    Result := EncodeDate(EY, EM, ED);
  Result := Result + EncodeTime(EH, EN, ES, 0);
end;

function InternalStrToTime(S: string): TDateTime;

var
  EH, EM, ES: Word;

begin
  EH := StrToInt(Copy(S, 1, 2));
  EM := StrToInt(Copy(S, 4, 2));
  ES := StrToInt(Copy(S, 7, 2));
  Result := EncodeTime(EH, EM, ES, 0);
end;

function InternalStrToTimeStamp(S: string): TDateTime;

var
  EY, EM, ED: Word;
  EH, EN, ES: Word;

begin
  EY := StrToInt(Copy(S, 1, 4));
  EM := StrToInt(Copy(S, 5, 2));
  ED := StrToInt(Copy(S, 7, 2));
  EH := StrToInt(Copy(S, 9, 2));
  EN := StrToInt(Copy(S, 11, 2));
  ES := StrToInt(Copy(S, 13, 2));
  if (EY = 0) or (EM = 0) or (ED = 0) then
    Result := 0
  else
    Result := EncodeDate(EY, EM, ED);
  Result := Result + EncodeTime(EH, EN, ES, 0);;
end;

function TMySQLConnection.MySQLWriteData(AType: enum_field_types;ASize: Integer; Source, Dest: PChar): Integer;

var
  VI: Integer;
  VF: Double;
  VD: TDateTime;
  Src : String;

begin
  Result := 0;
  If (Source<>Nil) Then
    Src:=StrPas(Source)
  else
    Src:='';
  case AType of
    FIELD_TYPE_TINY, FIELD_TYPE_SHORT, FIELD_TYPE_LONG, FIELD_TYPE_LONGLONG,
    FIELD_TYPE_INT24:
      begin
      Result:=SizeOf(Integer);
      if (Src<>'') then
        VI := StrToInt(Src)
      else
        VI := 0;
      Move(VI, Dest^, Result);
      end;
    FIELD_TYPE_DECIMAL, FIELD_TYPE_FLOAT, FIELD_TYPE_DOUBLE:
      begin
      Result := SizeOf(Double);
      if Src <> '' then
        VF := InternalStrToFloat(Src)
      else
        VF := 0;
      Move(VF, Dest^, Result);
      end;
    FIELD_TYPE_TIMESTAMP:
      begin
      Result := SizeOf(TDateTime);
      if Src <> '' then
        VD := InternalStrToTimeStamp(Src)
      else
        VD := 0;
      Move(VD, Dest^, Result);
      end;
    FIELD_TYPE_DATETIME:
      begin
      Result := SizeOf(TDateTime);
      if Src <> '' then
        VD := InternalStrToDateTime(Src)
      else
        VD := 0;
      Move(VD, Dest^, Result);
      end;
    FIELD_TYPE_DATE:
      begin
      Result := SizeOf(TDateTime);
      if Src <> '' then
        VD := InternalStrToDate(Src)
      else
        VD := 0;
      Move(VD, Dest^, Result);
      end;
    FIELD_TYPE_TIME:
      begin
      Result := SizeOf(TDateTime);
      if Src <> '' then
        VD := InternalStrToTime(Src)
      else
        VD := 0;
      Move(VD, Dest^, Result);
      end;
    FIELD_TYPE_VAR_STRING, FIELD_TYPE_STRING, FIELD_TYPE_ENUM, FIELD_TYPE_SET:
      begin
      Result := ASize;
{      Write('Moving string of size ',asize,' : ');
      P:=Source;
      If (P<>nil) then
        While P[0]<>#0 do
          begin
          Write(p[0]);
          inc(p);
          end;
      Writeln;
}      if Src<> '' then
        Move(Source^, Dest^, Result)
      else
        Dest^ := #0;
      end;
  end;
end;

procedure TMySQLConnection.UpdateIndexDefs(var IndexDefs : TIndexDefs;TableName : string);

var qry : TSQLQuery;

begin
  if not assigned(Transaction) then
    DatabaseError(SErrConnTransactionnSet);

  qry := tsqlquery.Create(nil);
  qry.transaction := Transaction;
  qry.database := Self;
  with qry do
    begin
    ReadOnly := True;
    sql.clear;
    sql.add('show index from ' +  TableName);
    open;
    end;

  while not qry.eof do with IndexDefs.AddIndexDef do
    begin
    Name := trim(qry.fieldbyname('Key_name').asstring);
    Fields := trim(qry.fieldbyname('Column_name').asstring);
    If Name = 'PRIMARY' then options := options + [ixPrimary];
    If qry.fieldbyname('Non_unique').asinteger = 0 then options := options + [ixUnique];
    qry.next;
{    while (name = qry.fields[0].asstring) and (not qry.eof) do
      begin
      Fields := Fields + ';' + trim(qry.Fields[2].asstring);
      qry.next;
      end;}
    end;
  qry.close;
  qry.free;
end;


function TMySQLConnection.GetTransactionHandle(trans: TSQLHandle): pointer;
begin
  Result:=Nil;
end;

function TMySQLConnection.Commit(trans: TSQLHandle): boolean;
begin
  // Do nothing.
end;

function TMySQLConnection.RollBack(trans: TSQLHandle): boolean;
begin
  // Do nothing
end;

function TMySQLConnection.StartdbTransaction(trans: TSQLHandle): boolean;
begin
  // Do nothing
end;

procedure TMySQLConnection.CommitRetaining(trans: TSQLHandle);
begin
  // Do nothing
end;

procedure TMySQLConnection.RollBackRetaining(trans: TSQLHandle);
begin
  // Do nothing
end;

end.