udr/client/FBTransaction.pas

(*
 *  Firebird Interface (fbintf). The fbintf components provide a set of
 *  Pascal language bindings for the Firebird API. Although predominantly
 *  a new development they include source code taken from IBX and may be
 *  considered a derived product. This software thus also includes the copyright
 *  notice and license conditions from IBX.
 *
 *  Except for those parts dervied from IBX, contents of this file are subject
 *  to the Initial Developer's Public License Version 1.0 (the "License"); you
 *  may not use this file except in compliance with the License. You may obtain a
 *  copy of the License here:
 *
 *    http://www.firebirdsql.org/index.php?op=doc&id=idpl
 *
 *  Software distributed under the License is distributed on an "AS
 *  IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
 *  implied. See the License for the specific language governing rights
 *  and limitations under the License.
 *
 *  The Initial Developer of the Original Code is Tony Whyman.
 *
 *  The Original Code is (C) 2016 Tony Whyman, MWA Software
 *  (http://www.mwasoftware.co.uk).
 *
 *  All Rights Reserved.
 *
 *  Contributor(s): ______________________________________.
 *
*)
{************************************************************************}
{                                                                        }
{       Borland Delphi Visual Component Library                          }
{       InterBase Express core components                                }
{                                                                        }
{       Copyright (c) 1998-2000 Inprise Corporation                      }
{                                                                        }
{    InterBase Express is based in part on the product                   }
{    Free IB Components, written by Gregory H. Deatz for                 }
{    Hoagland, Longo, Moran, Dunst & Doukas Company.                     }
{    Free IB Components is used under license.                           }
{                                                                        }
{    The contents of this file are subject to the InterBase              }
{    Public License Version 1.0 (the "License"); you may not             }
{    use this file except in compliance with the License. You            }
{    may obtain a copy of the License at http://www.Inprise.com/IPL.html }
{    Software distributed under the License is distributed on            }
{    an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either              }
{    express or implied. See the License for the specific language       }
{    governing rights and limitations under the License.                 }
{    The Original Code was created by InterBase Software Corporation     }
{       and its successors.                                              }
{    Portions created by Inprise Corporation are Copyright (C) Inprise   }
{       Corporation. All Rights Reserved.                                }
{    Contributor(s): Jeff Overcash                                       }
{                                                                        }
{    IBX For Lazarus (Firebird Express)                                  }
{    Contributor: Tony Whyman, MWA Software http://www.mwasoftware.co.uk }
{    Portions created by MWA Software are copyright McCallum Whyman      }
{    Associates Ltd 2011 - 2015                                                }
{                                                                        }
{************************************************************************}
unit FBTransaction;
{$IFDEF MSWINDOWS} 
{$DEFINE WINDOWS} 
{$ENDIF}

{$IFDEF FPC}
{$mode delphi}
{$interfaces COM}
{$ENDIF}

interface

uses
  Classes, SysUtils, IB, FBParamBlock, FBActivityMonitor, FBClientAPI;

type
  { TFBTransaction }

  TFBTransaction = class(TActivityReporter, IActivityMonitor,ITransaction)
  private
    FFirebirdAPI: TFBClientAPI;
    function GenerateTPB(sl: array of byte): ITPB;
  protected
    FTPB: ITPB;
    FSeqNo: integer;
    FDefaultCompletion: TTransactionAction;
    FAttachments: array of IAttachment; {Keep reference to attachment - ensures
                                          attachment cannot be freed before transaction}
    function GetActivityIntf(att: IAttachment): IActivityMonitor; virtual; abstract;
    procedure SetInterface(api: TFBClientAPI); virtual;
  public
    constructor Create(api: TFBClientAPI; Attachments: array of IAttachment; Params: array of byte; DefaultCompletion: TTransactionAction); overload;
    constructor Create(api: TFBClientAPI; Attachments: array of IAttachment; TPB: ITPB; DefaultCompletion: TTransactionAction); overload;
    constructor Create(api: TFBClientAPI; Attachment: IAttachment; Params: array of byte; DefaultCompletion: TTransactionAction); overload;
    constructor Create(api: TFBClientAPI; Attachment: IAttachment; TPB: ITPB; DefaultCompletion: TTransactionAction); overload;
    destructor Destroy; override;
    procedure DoDefaultTransactionEnd(Force: boolean);
    property FirebirdAPI: TFBClientAPI read FFirebirdAPI;

  public
    {ITransaction}
    function getTPB: ITPB;
    procedure PrepareForCommit;virtual; abstract;
    procedure Commit(Force: boolean=false);  virtual; abstract;
    procedure CommitRetaining;  virtual; abstract;
    function GetInTransaction: boolean; virtual; abstract;
    function GetAttachmentCount: integer;
    function GetAttachment(index: integer): IAttachment;
    procedure Rollback(Force: boolean=false);  virtual; abstract;
    procedure RollbackRetaining;  virtual; abstract;
    procedure Start(DefaultCompletion: TTransactionCompletion=taCommit); overload; virtual; abstract;
    procedure Start(TPB: ITPB; DefaultCompletion: TTransactionCompletion=taCommit); overload;

    property InTransaction: boolean read GetInTransaction;
    property TransactionSeqNo: integer read FSeqNo;
  end;

  {The transaction user interface is used to force an action on the end of the
   transaction.}

  ITransactionUser = interface
    ['{156fcdc9-a326-44b3-a82d-f23c6fb9f97c}']
    procedure TransactionEnding(aTransaction: ITransaction; Force: boolean);
  end;

  { TTPBItem }

  TTPBItem = class(TParamBlockItem,ITPBItem)
  public
    function getParamTypeName: AnsiString; override;
  end;

  { TTPB }

  TTPB = class (TCustomParamBlock<TTPBItem,ITPBItem>, ITPB)
  protected
    function LookupItemType(ParamTypeName: AnsiString): byte; override;
  public
    constructor Create(api: TFBClientAPI);
    function GetDPBParamTypeName(ParamType: byte): Ansistring;
  end;

implementation

uses FBMessages;

const
  isc_tpb_last_tpb_constant = isc_tpb_at_snapshot_number;

  TPBConstantNames: array[1..isc_tpb_last_tpb_constant] of string = (
    'consistency',
    'concurrency',
    'shared',
    'protected',
    'exclusive',
    'wait',
    'nowait',
    'read',
    'write',
    'lock_read',
    'lock_write',
    'verb_time',
    'commit_time',
    'ignore_limbo',
    'read_committed',
    'autocommit',
    'rec_version',
    'no_rec_version',
    'restart_requests',
    'no_auto_undo',
    'lock_timeout',
    'read_consistency',
    'at_snapshot_number'
  );

{ TFBTransaction }

function TFBTransaction.GenerateTPB(sl: array of byte): ITPB;
var
  i: Integer;
begin
  Result := TTPB.Create(FFirebirdAPI);
  for i := 0 to Length(sl) - 1 do
    Result.Add(sl[i]);
end;

procedure TFBTransaction.SetInterface(api: TFBClientAPI);
begin
  FFirebirdAPI := api;
end;

constructor TFBTransaction.Create(api: TFBClientAPI; Attachments: array of IAttachment;
  Params: array of byte; DefaultCompletion: TTransactionAction);
begin
  Create(api, Attachments,GenerateTPB(Params), DefaultCompletion);
end;

constructor TFBTransaction.Create(api: TFBClientAPI; Attachments: array of IAttachment; TPB: ITPB;
  DefaultCompletion: TTransactionAction);
var
  i: Integer;
begin
  inherited Create(nil);
  SetInterface(api);
  if Length(Attachments) = 0 then
    IBError(ibxeEmptyAttachmentsList,[nil]);

  {make sure all attachments use same Firebird API}
  for i := 0 to Length(Attachments) - 1 do
    if Attachments[i].getFirebirdAPI.GetFBLibrary.GetHandle <> FFirebirdAPI.GetFBLibrary.GetHandle then
      IBError(ibxeDifferentAPIs,[nil]);

  SetLength(FAttachments,Length(Attachments));
  for i := 0 to Length(Attachments) - 1 do
  begin
    AddMonitor(GetActivityIntf(Attachments[i]));
    FAttachments[i] := Attachments[i];
  end;
  FTPB := TPB;
  Start(DefaultCompletion);
end;

constructor TFBTransaction.Create(api: TFBClientAPI; Attachment: IAttachment;
  Params: array of byte; DefaultCompletion: TTransactionAction);
begin
  Create(api,Attachment,GenerateTPB(Params),DefaultCompletion);
end;

constructor TFBTransaction.Create(api: TFBClientAPI; Attachment: IAttachment; TPB: ITPB;
  DefaultCompletion: TTransactionAction);
begin
  inherited Create(nil);
  SetInterface(api);
  AddMonitor(GetActivityIntf(Attachment));
  SetLength(FAttachments,1);
  FAttachments[0] := Attachment;
  FTPB := TPB;
  Start(DefaultCompletion);
end;

destructor TFBTransaction.Destroy;
begin
  DoDefaultTransactionEnd(false);
  inherited Destroy;
end;

procedure TFBTransaction.DoDefaultTransactionEnd(Force: boolean);
var i: integer;
    intf: IUnknown;
    user: ITransactionUser;
begin
  if InTransaction then
  begin
    for i := 0 to InterfaceCount - 1 do
    begin
      intf := GetInterface(i);
      if (intf <> nil) and  (intf.QueryInterface(ITransactionUser,user) = S_OK) then
        user.TransactionEnding(self,Force);
    end;
    case FDefaultCompletion of
    taRollback:
      Rollback(Force);
    taCommit:
      Commit(Force);
    end;
  end;
end;

function TFBTransaction.getTPB: ITPB;
begin
  Result := FTPB;
end;

function TFBTransaction.GetAttachmentCount: integer;
begin
  Result := Length(FAttachments);
end;

function TFBTransaction.GetAttachment(index: integer): IAttachment;
begin
  if (index >= 0) and (index < Length(FAttachments)) then
    Result := FAttachments[index]
  else
    IBError(ibxeAttachmentListIndexError,[index]);
end;

procedure TFBTransaction.Start(TPB: ITPB; DefaultCompletion: TTransactionCompletion
  );
begin
  FTPB := TPB;
  Start(DefaultCompletion);
end;

{ TTPBItem }

function TTPBItem.getParamTypeName: AnsiString;
begin
  Result :=  TPBPrefix + TPBConstantNames[getParamType];
end;


{TTPB}

constructor TTPB.Create(api: TFBClientAPI);
begin
  inherited Create(api);
  FDataLength := 1;
  FBuffer^ := isc_tpb_version3;
end;

function TTPB.GetDPBParamTypeName(ParamType: byte): Ansistring;
begin
  if ParamType <= isc_tpb_last_tpb_constant then
    Result := TPBConstantNames[ParamType]
  else
    Result := '';
end;

function TTPB.LookupItemType(ParamTypeName: AnsiString): byte;
var i: byte;
begin
  Result := 0;
  ParamTypeName := LowerCase(ParamTypeName);
  if (Pos(TPBPrefix, ParamTypeName) = 1) then
    Delete(ParamTypeName, 1, Length(TPBPrefix));

  for i := 1 to isc_tpb_last_tpb_constant do
    if (ParamTypeName = TPBConstantNames[i]) then
    begin
      Result := i;
      break;
    end;
end;

end.

Revision:	315
Committed:	Thu Feb 25 11:56:36 2021 UTC (3 years, 8 months ago) by tony
Content type:	text/x-pascal
Original Path:	*ibx/trunk/fbintf/client/FBTransaction.pas*
File size:	11078 byte(s)
Log Message:	Updated for IBX 4 release
#	Content
1	(*
2	* Firebird Interface (fbintf). The fbintf components provide a set of
3	* Pascal language bindings for the Firebird API. Although predominantly
4	* a new development they include source code taken from IBX and may be
5	* considered a derived product. This software thus also includes the copyright
6	* notice and license conditions from IBX.
7	*
8	* Except for those parts dervied from IBX, contents of this file are subject
9	* to the Initial Developer's Public License Version 1.0 (the "License"); you
10	* may not use this file except in compliance with the License. You may obtain a
11	* copy of the License here:
12	*
13	* http://www.firebirdsql.org/index.php?op=doc&id=idpl
14	*
15	* Software distributed under the License is distributed on an "AS
16	* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
17	* implied. See the License for the specific language governing rights
18	* and limitations under the License.
19	*
20	* The Initial Developer of the Original Code is Tony Whyman.
21	*
22	* The Original Code is (C) 2016 Tony Whyman, MWA Software
23	* (http://www.mwasoftware.co.uk).
24	*
25	* All Rights Reserved.
26	*
27	* Contributor(s): ______________________________________.
28	*
29	*)
30	{************************************************************************}
31	{ }
32	{ Borland Delphi Visual Component Library }
33	{ InterBase Express core components }
34	{ }
35	{ Copyright (c) 1998-2000 Inprise Corporation }
36	{ }
37	{ InterBase Express is based in part on the product }
38	{ Free IB Components, written by Gregory H. Deatz for }
39	{ Hoagland, Longo, Moran, Dunst & Doukas Company. }
40	{ Free IB Components is used under license. }
41	{ }
42	{ The contents of this file are subject to the InterBase }
43	{ Public License Version 1.0 (the "License"); you may not }
44	{ use this file except in compliance with the License. You }
45	{ may obtain a copy of the License at http://www.Inprise.com/IPL.html }
46	{ Software distributed under the License is distributed on }
47	{ an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either }
48	{ express or implied. See the License for the specific language }
49	{ governing rights and limitations under the License. }
50	{ The Original Code was created by InterBase Software Corporation }
51	{ and its successors. }
52	{ Portions created by Inprise Corporation are Copyright (C) Inprise }
53	{ Corporation. All Rights Reserved. }
54	{ Contributor(s): Jeff Overcash }
55	{ }
56	{ IBX For Lazarus (Firebird Express) }
57	{ Contributor: Tony Whyman, MWA Software http://www.mwasoftware.co.uk }
58	{ Portions created by MWA Software are copyright McCallum Whyman }
59	{ Associates Ltd 2011 - 2015 }
60	{ }
61	{************************************************************************}
62	unit FBTransaction;
63	{$IFDEF MSWINDOWS}
64	{$DEFINE WINDOWS}
65	{$ENDIF}
66
67	{$IFDEF FPC}
68	{$mode delphi}
69	{$interfaces COM}
70	{$ENDIF}
71
72	interface
73
74	uses
75	Classes, SysUtils, IB, FBParamBlock, FBActivityMonitor, FBClientAPI;
76
77	type
78	{ TFBTransaction }
79
80	TFBTransaction = class(TActivityReporter, IActivityMonitor,ITransaction)
81	private
82	FFirebirdAPI: TFBClientAPI;
83	function GenerateTPB(sl: array of byte): ITPB;
84	protected
85	FTPB: ITPB;
86	FSeqNo: integer;
87	FDefaultCompletion: TTransactionAction;
88	FAttachments: array of IAttachment; {Keep reference to attachment - ensures
89	attachment cannot be freed before transaction}
90	function GetActivityIntf(att: IAttachment): IActivityMonitor; virtual; abstract;
91	procedure SetInterface(api: TFBClientAPI); virtual;
92	public
93	constructor Create(api: TFBClientAPI; Attachments: array of IAttachment; Params: array of byte; DefaultCompletion: TTransactionAction); overload;
94	constructor Create(api: TFBClientAPI; Attachments: array of IAttachment; TPB: ITPB; DefaultCompletion: TTransactionAction); overload;
95	constructor Create(api: TFBClientAPI; Attachment: IAttachment; Params: array of byte; DefaultCompletion: TTransactionAction); overload;
96	constructor Create(api: TFBClientAPI; Attachment: IAttachment; TPB: ITPB; DefaultCompletion: TTransactionAction); overload;
97	destructor Destroy; override;
98	procedure DoDefaultTransactionEnd(Force: boolean);
99	property FirebirdAPI: TFBClientAPI read FFirebirdAPI;
100
101	public
102	{ITransaction}
103	function getTPB: ITPB;
104	procedure PrepareForCommit;virtual; abstract;
105	procedure Commit(Force: boolean=false); virtual; abstract;
106	procedure CommitRetaining; virtual; abstract;
107	function GetInTransaction: boolean; virtual; abstract;
108	function GetAttachmentCount: integer;
109	function GetAttachment(index: integer): IAttachment;
110	procedure Rollback(Force: boolean=false); virtual; abstract;
111	procedure RollbackRetaining; virtual; abstract;
112	procedure Start(DefaultCompletion: TTransactionCompletion=taCommit); overload; virtual; abstract;
113	procedure Start(TPB: ITPB; DefaultCompletion: TTransactionCompletion=taCommit); overload;
114
115	property InTransaction: boolean read GetInTransaction;
116	property TransactionSeqNo: integer read FSeqNo;
117	end;
118
119	{The transaction user interface is used to force an action on the end of the
120	transaction.}
121
122	ITransactionUser = interface
123	['{156fcdc9-a326-44b3-a82d-f23c6fb9f97c}']
124	procedure TransactionEnding(aTransaction: ITransaction; Force: boolean);
125	end;
126
127	{ TTPBItem }
128
129	TTPBItem = class(TParamBlockItem,ITPBItem)
130	public
131	function getParamTypeName: AnsiString; override;
132	end;
133
134	{ TTPB }
135
136	TTPB = class (TCustomParamBlock<TTPBItem,ITPBItem>, ITPB)
137	protected
138	function LookupItemType(ParamTypeName: AnsiString): byte; override;
139	public
140	constructor Create(api: TFBClientAPI);
141	function GetDPBParamTypeName(ParamType: byte): Ansistring;
142	end;
143
144	implementation
145
146	uses FBMessages;
147
148	const
149	isc_tpb_last_tpb_constant = isc_tpb_at_snapshot_number;
150
151	TPBConstantNames: array[1..isc_tpb_last_tpb_constant] of string = (
152	'consistency',
153	'concurrency',
154	'shared',
155	'protected',
156	'exclusive',
157	'wait',
158	'nowait',
159	'read',
160	'write',
161	'lock_read',
162	'lock_write',
163	'verb_time',
164	'commit_time',
165	'ignore_limbo',
166	'read_committed',
167	'autocommit',
168	'rec_version',
169	'no_rec_version',
170	'restart_requests',
171	'no_auto_undo',
172	'lock_timeout',
173	'read_consistency',
174	'at_snapshot_number'
175	);
176
177	{ TFBTransaction }
178
179	function TFBTransaction.GenerateTPB(sl: array of byte): ITPB;
180	var
181	i: Integer;
182	begin
183	Result := TTPB.Create(FFirebirdAPI);
184	for i := 0 to Length(sl) - 1 do
185	Result.Add(sl[i]);
186	end;
187
188	procedure TFBTransaction.SetInterface(api: TFBClientAPI);
189	begin
190	FFirebirdAPI := api;
191	end;
192
193	constructor TFBTransaction.Create(api: TFBClientAPI; Attachments: array of IAttachment;
194	Params: array of byte; DefaultCompletion: TTransactionAction);
195	begin
196	Create(api, Attachments,GenerateTPB(Params), DefaultCompletion);
197	end;
198
199	constructor TFBTransaction.Create(api: TFBClientAPI; Attachments: array of IAttachment; TPB: ITPB;
200	DefaultCompletion: TTransactionAction);
201	var
202	i: Integer;
203	begin
204	inherited Create(nil);
205	SetInterface(api);
206	if Length(Attachments) = 0 then
207	IBError(ibxeEmptyAttachmentsList,[nil]);
208
209	{make sure all attachments use same Firebird API}
210	for i := 0 to Length(Attachments) - 1 do
211	if Attachments[i].getFirebirdAPI.GetFBLibrary.GetHandle <> FFirebirdAPI.GetFBLibrary.GetHandle then
212	IBError(ibxeDifferentAPIs,[nil]);
213
214	SetLength(FAttachments,Length(Attachments));
215	for i := 0 to Length(Attachments) - 1 do
216	begin
217	AddMonitor(GetActivityIntf(Attachments[i]));
218	FAttachments[i] := Attachments[i];
219	end;
220	FTPB := TPB;
221	Start(DefaultCompletion);
222	end;
223
224	constructor TFBTransaction.Create(api: TFBClientAPI; Attachment: IAttachment;
225	Params: array of byte; DefaultCompletion: TTransactionAction);
226	begin
227	Create(api,Attachment,GenerateTPB(Params),DefaultCompletion);
228	end;
229
230	constructor TFBTransaction.Create(api: TFBClientAPI; Attachment: IAttachment; TPB: ITPB;
231	DefaultCompletion: TTransactionAction);
232	begin
233	inherited Create(nil);
234	SetInterface(api);
235	AddMonitor(GetActivityIntf(Attachment));
236	SetLength(FAttachments,1);
237	FAttachments[0] := Attachment;
238	FTPB := TPB;
239	Start(DefaultCompletion);
240	end;
241
242	destructor TFBTransaction.Destroy;
243	begin
244	DoDefaultTransactionEnd(false);
245	inherited Destroy;
246	end;
247
248	procedure TFBTransaction.DoDefaultTransactionEnd(Force: boolean);
249	var i: integer;
250	intf: IUnknown;
251	user: ITransactionUser;
252	begin
253	if InTransaction then
254	begin
255	for i := 0 to InterfaceCount - 1 do
256	begin
257	intf := GetInterface(i);
258	if (intf <> nil) and (intf.QueryInterface(ITransactionUser,user) = S_OK) then
259	user.TransactionEnding(self,Force);
260	end;
261	case FDefaultCompletion of
262	taRollback:
263	Rollback(Force);
264	taCommit:
265	Commit(Force);
266	end;
267	end;
268	end;
269
270	function TFBTransaction.getTPB: ITPB;
271	begin
272	Result := FTPB;
273	end;
274
275	function TFBTransaction.GetAttachmentCount: integer;
276	begin
277	Result := Length(FAttachments);
278	end;
279
280	function TFBTransaction.GetAttachment(index: integer): IAttachment;
281	begin
282	if (index >= 0) and (index < Length(FAttachments)) then
283	Result := FAttachments[index]
284	else
285	IBError(ibxeAttachmentListIndexError,[index]);
286	end;
287
288	procedure TFBTransaction.Start(TPB: ITPB; DefaultCompletion: TTransactionCompletion
289	);
290	begin
291	FTPB := TPB;
292	Start(DefaultCompletion);
293	end;
294
295	{ TTPBItem }
296
297	function TTPBItem.getParamTypeName: AnsiString;
298	begin
299	Result := TPBPrefix + TPBConstantNames[getParamType];
300	end;
301
302
303	{TTPB}
304
305	constructor TTPB.Create(api: TFBClientAPI);
306	begin
307	inherited Create(api);
308	FDataLength := 1;
309	FBuffer^ := isc_tpb_version3;
310	end;
311
312	function TTPB.GetDPBParamTypeName(ParamType: byte): Ansistring;
313	begin
314	if ParamType <= isc_tpb_last_tpb_constant then
315	Result := TPBConstantNames[ParamType]
316	else
317	Result := '';
318	end;
319
320	function TTPB.LookupItemType(ParamTypeName: AnsiString): byte;
321	var i: byte;
322	begin
323	Result := 0;
324	ParamTypeName := LowerCase(ParamTypeName);
325	if (Pos(TPBPrefix, ParamTypeName) = 1) then
326	Delete(ParamTypeName, 1, Length(TPBPrefix));
327
328	for i := 1 to isc_tpb_last_tpb_constant do
329	if (ParamTypeName = TPBConstantNames[i]) then
330	begin
331	Result := i;
332	break;
333	end;
334	end;
335
336	end.
337