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
#	User	Rev	Content
1	tony	45	(*
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	tony	56	{$IFDEF MSWINDOWS}
64			{$DEFINE WINDOWS}
65			{$ENDIF}
66	tony	45
67			{$IFDEF FPC}
68	tony	56	{$mode delphi}
69	tony	45	{$interfaces COM}
70			{$ENDIF}
71
72			interface
73
74			uses
75	tony	263	Classes, SysUtils, IB, FBParamBlock, FBActivityMonitor, FBClientAPI;
76	tony	45
77			type
78			{ TFBTransaction }
79
80			TFBTransaction = class(TActivityReporter, IActivityMonitor,ITransaction)
81			private
82	tony	263	FFirebirdAPI: TFBClientAPI;
83	tony	45	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	tony	263	procedure SetInterface(api: TFBClientAPI); virtual;
92	tony	45	public
93	tony	263	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	tony	45	destructor Destroy; override;
98			procedure DoDefaultTransactionEnd(Force: boolean);
99	tony	263	property FirebirdAPI: TFBClientAPI read FFirebirdAPI;
100	tony	45
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	tony	315	{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	tony	45	implementation
145
146	tony	315	uses FBMessages;
147	tony	45
148	tony	315	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	tony	45	{ TFBTransaction }
178
179			function TFBTransaction.GenerateTPB(sl: array of byte): ITPB;
180			var
181			i: Integer;
182			begin
183	tony	263	Result := TTPB.Create(FFirebirdAPI);
184	tony	45	for i := 0 to Length(sl) - 1 do
185			Result.Add(sl[i]);
186			end;
187
188	tony	263	procedure TFBTransaction.SetInterface(api: TFBClientAPI);
189			begin
190			FFirebirdAPI := api;
191			end;
192
193			constructor TFBTransaction.Create(api: TFBClientAPI; Attachments: array of IAttachment;
194	tony	45	Params: array of byte; DefaultCompletion: TTransactionAction);
195			begin
196	tony	263	Create(api, Attachments,GenerateTPB(Params), DefaultCompletion);
197	tony	45	end;
198
199	tony	263	constructor TFBTransaction.Create(api: TFBClientAPI; Attachments: array of IAttachment; TPB: ITPB;
200	tony	45	DefaultCompletion: TTransactionAction);
201			var
202			i: Integer;
203			begin
204			inherited Create(nil);
205	tony	263	SetInterface(api);
206	tony	45	if Length(Attachments) = 0 then
207			IBError(ibxeEmptyAttachmentsList,[nil]);
208
209	tony	263	{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	tony	45	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	tony	263	constructor TFBTransaction.Create(api: TFBClientAPI; Attachment: IAttachment;
225	tony	45	Params: array of byte; DefaultCompletion: TTransactionAction);
226			begin
227	tony	263	Create(api,Attachment,GenerateTPB(Params),DefaultCompletion);
228	tony	45	end;
229
230	tony	263	constructor TFBTransaction.Create(api: TFBClientAPI; Attachment: IAttachment; TPB: ITPB;
231	tony	45	DefaultCompletion: TTransactionAction);
232			begin
233			inherited Create(nil);
234	tony	263	SetInterface(api);
235	tony	45	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	tony	315	intf: IUnknown;
251			user: ITransactionUser;
252	tony	45	begin
253			if InTransaction then
254			begin
255			for i := 0 to InterfaceCount - 1 do
256			begin
257			intf := GetInterface(i);
258	tony	315	if (intf <> nil) and (intf.QueryInterface(ITransactionUser,user) = S_OK) then
259			user.TransactionEnding(self,Force);
260	tony	45	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	tony	315	{ 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	tony	45	end.
337