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{************************************************************************} |
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{ } |
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{ Borland Delphi Visual Component Library } |
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{ InterBase Express core components } |
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{ } |
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{ Copyright (c) 1998-2000 Inprise Corporation } |
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{ } |
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{ InterBase Express is based in part on the product } |
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{ Free IB Components, written by Gregory H. Deatz for } |
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{ Hoagland, Longo, Moran, Dunst & Doukas Company. } |
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{ Free IB Components is used under license. } |
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{ } |
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{ The contents of this file are subject to the InterBase } |
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{ Public License Version 1.0 (the "License"); you may not } |
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{ use this file except in compliance with the License. You } |
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{ may obtain a copy of the License at http://www.Inprise.com/IPL.html } |
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{ Software distributed under the License is distributed on } |
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{ an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either } |
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{ express or implied. See the License for the specific language } |
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{ governing rights and limitations under the License. } |
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{ The Original Code was created by InterBase Software Corporation } |
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{ and its successors. } |
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{ Portions created by Inprise Corporation are Copyright (C) Inprise } |
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{ Corporation. All Rights Reserved. } |
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{ Contributor(s): Jeff Overcash } |
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{ } |
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{ IBX For Lazarus (Firebird Express) } |
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{ Contributor: Tony Whyman, MWA Software http://www.mwasoftware.co.uk } |
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{ Portions created by MWA Software are copyright McCallum Whyman } |
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{ Associates Ltd 2011 } |
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{************************************************************************} |
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|
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unit IBBlob; |
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|
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{$Mode Delphi} |
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|
37 |
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interface |
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|
39 |
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uses |
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SysUtils, Classes, IBHeader, IBErrorCodes, IBExternals, DB, IB, IBDatabase; |
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|
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|
43 |
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const |
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DefaultBlobSegmentSize = 16 * 1024; |
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|
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type |
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{ TIBBlobStream } |
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TIBBlobStream = class(TStream) |
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private |
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FBase: TIBBase; |
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FBlobID: TISC_QUAD; |
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FBlobMaxSegmentSize: Int64; |
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FBlobNumSegments: Int64; |
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FBlobSize: Int64; |
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FBlobType: Short; { 0 = segmented, 1 = streamed } |
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FBuffer: PChar; |
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FBlobInitialized: Boolean; |
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FHandle: TISC_BLOB_HANDLE; |
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FMode: TBlobStreamMode; |
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FModified: Boolean; |
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FPosition: Int64; |
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protected |
63 |
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procedure CloseBlob; |
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procedure CreateBlob; |
65 |
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procedure EnsureBlobInitialized; |
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procedure GetBlobInfo; |
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function GetDatabase: TIBDatabase; |
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function GetDBHandle: PISC_DB_HANDLE; |
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function GetTransaction: TIBTransaction; |
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function GetTRHandle: PISC_TR_HANDLE; |
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procedure OpenBlob; |
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procedure SetBlobID(Value: TISC_QUAD); |
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procedure SetDatabase(Value: TIBDatabase); |
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procedure SetMode(Value: TBlobStreamMode); |
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procedure SetTransaction(Value: TIBTransaction); |
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public |
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constructor Create; |
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destructor Destroy; override; |
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function Call(ErrCode: ISC_STATUS; RaiseError: Boolean): ISC_STATUS; |
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procedure CheckReadable; |
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procedure CheckWritable; |
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procedure Finalize; |
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procedure LoadFromFile(Filename: string); |
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procedure LoadFromStream(Stream: TStream); |
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function Read(var Buffer; Count: Longint): Longint; override; |
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procedure SaveToFile(Filename: string); |
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procedure SaveToStream(Stream: TStream); |
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function Seek(const Offset: Int64; Origin: TSeekOrigin): Int64; override; |
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procedure SetSize(const NewSize: Int64); override; |
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procedure SetSize(NewSize: Longint); override; |
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procedure Truncate; |
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function Write(const Buffer; Count: Longint): Longint; override; |
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property Handle: TISC_BLOB_HANDLE read FHandle; |
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property BlobID: TISC_QUAD read FBlobID write SetBlobID; |
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property BlobMaxSegmentSize: Int64 read FBlobMaxSegmentSize; |
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property BlobNumSegments: Int64 read FBlobNumSegments; |
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property BlobSize: Int64 read FBlobSize; |
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property BlobType: Short read FBlobType; |
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property Database: TIBDatabase read GetDatabase write SetDatabase; |
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property DBHandle: PISC_DB_HANDLE read GetDBHandle; |
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property Mode: TBlobStreamMode read FMode write SetMode; |
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property Modified: Boolean read FModified; |
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property Transaction: TIBTransaction read GetTransaction write SetTransaction; |
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property TRHandle: PISC_TR_HANDLE read GetTRHandle; |
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end; |
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|
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procedure GetBlobInfo(hBlobHandle: PISC_BLOB_HANDLE; var NumSegments: Int64; var MaxSegmentSize, |
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TotalSize: Int64; var BlobType: Short); |
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procedure ReadBlob(hBlobHandle: PISC_BLOB_HANDLE; Buffer: PChar; BlobSize: Int64); |
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procedure WriteBlob(hBlobHandle: PISC_BLOB_HANDLE; Buffer: PChar; BlobSize: Int64); |
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|
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implementation |
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|
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uses IBIntf; |
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|
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procedure GetBlobInfo(hBlobHandle: PISC_BLOB_HANDLE; var NumSegments: Int64; var MaxSegmentSize, |
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TotalSize: Int64; var BlobType: Short); |
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var |
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items: array[0..3] of Char; |
120 |
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results: array[0..99] of Char; |
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i, item_length: Integer; |
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item: Integer; |
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begin |
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items[0] := Char(isc_info_blob_num_segments); |
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items[1] := Char(isc_info_blob_max_segment); |
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items[2] := Char(isc_info_blob_total_length); |
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items[3] := Char(isc_info_blob_type); |
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|
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if isc_blob_info(StatusVector, hBlobHandle, 4, @items[0], SizeOf(results), |
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@results[0]) > 0 then |
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IBDatabaseError; |
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|
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i := 0; |
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while (i < SizeOf(results)) and (results[i] <> Char(isc_info_end)) do |
135 |
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begin |
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item := Integer(results[i]); Inc(i); |
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item_length := isc_vax_integer(@results[i], 2); Inc(i, 2); |
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case item of |
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isc_info_blob_num_segments: |
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NumSegments := isc_portable_integer(@results[i], item_length); |
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isc_info_blob_max_segment: |
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MaxSegmentSize := isc_portable_integer(@results[i], item_length); |
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isc_info_blob_total_length: |
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TotalSize := isc_portable_integer(@results[i], item_length); |
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isc_info_blob_type: |
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BlobType := isc_portable_integer(@results[i], item_length); |
147 |
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end; |
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Inc(i, item_length); |
149 |
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end; |
150 |
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end; |
151 |
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|
152 |
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procedure ReadBlob(hBlobHandle: PISC_BLOB_HANDLE; Buffer: PChar; BlobSize: Int64); |
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var |
154 |
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CurPos: Int64; |
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BytesRead, SegLen: UShort; |
156 |
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LocalBuffer: PChar; |
157 |
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begin |
158 |
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CurPos := 0; |
159 |
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LocalBuffer := Buffer; |
160 |
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SegLen := UShort(DefaultBlobSegmentSize); |
161 |
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while (CurPos < BlobSize) do |
162 |
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begin |
163 |
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if (CurPos + SegLen > BlobSize) then |
164 |
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SegLen := BlobSize - CurPos; |
165 |
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if not ((isc_get_segment(StatusVector, hBlobHandle, @BytesRead, SegLen, |
166 |
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LocalBuffer) = 0) or |
167 |
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(StatusVectorArray[1] = isc_segment)) then |
168 |
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IBDatabaseError; |
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Inc(LocalBuffer, BytesRead); |
170 |
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Inc(CurPos, BytesRead); |
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BytesRead := 0; |
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end; |
173 |
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end; |
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|
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procedure WriteBlob(hBlobHandle: PISC_BLOB_HANDLE; Buffer: PChar; |
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BlobSize: Int64); |
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var |
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CurPos: Int64; |
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SegLen: Long; |
180 |
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begin |
181 |
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CurPos := 0; |
182 |
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SegLen := DefaultBlobSegmentSize; |
183 |
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while (CurPos < BlobSize) do |
184 |
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begin |
185 |
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if (CurPos + SegLen > BlobSize) then |
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SegLen := BlobSize - CurPos; |
187 |
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if isc_put_segment(StatusVector, hBlobHandle, SegLen, |
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PChar(@Buffer[CurPos])) > 0 then |
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IBDatabaseError; |
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Inc(CurPos, SegLen); |
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end; |
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end; |
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|
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|
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{ TIBBlobStream } |
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constructor TIBBlobStream.Create; |
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begin |
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inherited Create; |
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FBase := TIBBase.Create(Self); |
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FBuffer := nil; |
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FBlobSize := 0; |
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end; |
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|
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destructor TIBBlobStream.Destroy; |
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begin |
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if (FHandle <> nil) and |
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(Call(isc_close_blob(StatusVector, @FHandle), False) > 0) then |
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IBDataBaseError; |
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FBase.Free; |
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SetSize(0); |
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inherited Destroy; |
212 |
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end; |
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|
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function TIBBlobStream.Call(ErrCode: ISC_STATUS; RaiseError: Boolean): ISC_STATUS; |
215 |
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begin |
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result := 0; |
217 |
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if Transaction <> nil then |
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result := Transaction.Call(ErrCode, RaiseError) |
219 |
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else if RaiseError and (ErrCode > 0) then |
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IBDataBaseError; |
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end; |
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|
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procedure TIBBlobStream.CheckReadable; |
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begin |
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if FMode = bmWrite then IBError(ibxeBlobCannotBeRead, [nil]); |
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end; |
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|
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procedure TIBBlobStream.CheckWritable; |
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begin |
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if FMode = bmRead then IBError(ibxeBlobCannotBeWritten, [nil]); |
231 |
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end; |
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|
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procedure TIBBlobStream.CloseBlob; |
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begin |
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Finalize; |
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if (FHandle <> nil) and |
237 |
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(Call(isc_close_blob(StatusVector, @FHandle), False) > 0) then |
238 |
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IBDataBaseError; |
239 |
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end; |
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|
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procedure TIBBlobStream.CreateBlob; |
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begin |
243 |
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CheckWritable; |
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FBlobID.gds_quad_high := 0; |
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FBlobID.gds_quad_low := 0; |
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Truncate; |
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end; |
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|
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procedure TIBBlobStream.EnsureBlobInitialized; |
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begin |
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if not FBlobInitialized then |
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case FMode of |
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bmWrite: |
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CreateBlob; |
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bmReadWrite: begin |
256 |
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if (FBlobID.gds_quad_high = 0) and |
257 |
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(FBlobID.gds_quad_low = 0) then |
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CreateBlob |
259 |
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else |
260 |
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OpenBlob; |
261 |
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end; |
262 |
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else |
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OpenBlob; |
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end; |
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FBlobInitialized := True; |
266 |
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end; |
267 |
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|
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procedure TIBBlobStream.Finalize; |
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begin |
270 |
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if (not FBlobInitialized) or (FMode = bmRead) or (not FModified) then |
271 |
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exit; |
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{ need to start writing to a blob, create one } |
273 |
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Call(isc_create_blob2(StatusVector, DBHandle, TRHandle, @FHandle, @FBlobID, |
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0, nil), True); |
275 |
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IBBlob.WriteBlob(@FHandle, FBuffer, FBlobSize); |
276 |
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Call(isc_close_blob(StatusVector, @FHandle), True); |
277 |
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FModified := False; |
278 |
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end; |
279 |
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|
280 |
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procedure TIBBlobStream.GetBlobInfo; |
281 |
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var |
282 |
< |
iBlobSize: Int64; |
283 |
< |
begin |
284 |
< |
IBBlob.GetBlobInfo(@FHandle, FBlobNumSegments, FBlobMaxSegmentSize, |
285 |
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iBlobSize, FBlobType); |
286 |
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SetSize(iBlobSize); |
287 |
< |
end; |
288 |
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|
289 |
< |
function TIBBlobStream.GetDatabase: TIBDatabase; |
290 |
< |
begin |
291 |
< |
result := FBase.Database; |
292 |
< |
end; |
293 |
< |
|
294 |
< |
function TIBBlobStream.GetDBHandle: PISC_DB_HANDLE; |
295 |
< |
begin |
296 |
< |
result := FBase.DBHandle; |
297 |
< |
end; |
298 |
< |
|
299 |
< |
function TIBBlobStream.GetTransaction: TIBTransaction; |
300 |
< |
begin |
301 |
< |
result := FBase.Transaction; |
302 |
< |
end; |
303 |
< |
|
304 |
< |
function TIBBlobStream.GetTRHandle: PISC_TR_HANDLE; |
305 |
< |
begin |
306 |
< |
result := FBase.TRHandle; |
307 |
< |
end; |
308 |
< |
|
309 |
< |
procedure TIBBlobStream.LoadFromFile(Filename: string); |
310 |
< |
var |
311 |
< |
Stream: TStream; |
312 |
< |
begin |
313 |
< |
Stream := TFileStream.Create(FileName, fmOpenRead); |
314 |
< |
try |
315 |
< |
LoadFromStream(Stream); |
316 |
< |
finally |
317 |
< |
Stream.Free; |
318 |
< |
end; |
319 |
< |
end; |
320 |
< |
|
321 |
< |
procedure TIBBlobStream.LoadFromStream(Stream: TStream); |
322 |
< |
begin |
323 |
< |
CheckWritable; |
324 |
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EnsureBlobInitialized; |
325 |
< |
Stream.Position := 0; |
326 |
< |
SetSize(Stream.Size); |
327 |
< |
if FBlobSize <> 0 then |
328 |
< |
Stream.ReadBuffer(FBuffer^, FBlobSize); |
329 |
< |
FModified := True; |
330 |
< |
end; |
331 |
< |
|
332 |
< |
procedure TIBBlobStream.OpenBlob; |
333 |
< |
begin |
334 |
< |
CheckReadable; |
335 |
< |
Call(isc_open_blob2(StatusVector, DBHandle, TRHandle, @FHandle, |
336 |
< |
@FBlobID, 0, nil), True); |
337 |
< |
try |
338 |
< |
GetBlobInfo; |
339 |
< |
SetSize(FBlobSize); |
340 |
< |
IBBlob.ReadBlob(@FHandle, FBuffer, FBlobSize); |
341 |
< |
except |
342 |
< |
Call(isc_close_blob(StatusVector, @FHandle), False); |
343 |
< |
raise; |
344 |
< |
end; |
345 |
< |
Call(isc_close_blob(StatusVector, @FHandle), True); |
346 |
< |
end; |
347 |
< |
|
348 |
< |
function TIBBlobStream.Read(var Buffer; Count: Longint): Longint; |
349 |
< |
begin |
350 |
< |
CheckReadable; |
351 |
< |
EnsureBlobInitialized; |
352 |
< |
if (Count <= 0) then |
353 |
< |
begin |
354 |
< |
result := 0; |
355 |
< |
exit; |
356 |
< |
end; |
357 |
< |
if (FPosition + Count > FBlobSize) then |
358 |
< |
result := FBlobSize - FPosition |
359 |
< |
else |
360 |
< |
result := Count; |
361 |
< |
Move(FBuffer[FPosition], Buffer, result); |
362 |
< |
Inc(FPosition, Result); |
363 |
< |
end; |
364 |
< |
|
365 |
< |
procedure TIBBlobStream.SaveToFile(Filename: string); |
366 |
< |
var |
367 |
< |
Stream: TStream; |
368 |
< |
begin |
369 |
< |
Stream := TFileStream.Create(FileName, fmCreate); |
370 |
< |
try |
371 |
< |
SaveToStream(Stream); |
372 |
< |
finally |
373 |
< |
Stream.Free; |
374 |
< |
end; |
375 |
< |
end; |
376 |
< |
|
377 |
< |
procedure TIBBlobStream.SaveToStream(Stream: TStream); |
378 |
< |
begin |
379 |
< |
CheckReadable; |
380 |
< |
EnsureBlobInitialized; |
381 |
< |
if FBlobSize <> 0 then |
382 |
< |
begin |
383 |
< |
Seek(0, soFromBeginning); |
384 |
< |
Stream.WriteBuffer(FBuffer^, FBlobSize); |
385 |
< |
end; |
386 |
< |
end; |
387 |
< |
|
388 |
< |
function TIBBlobStream.Seek(const Offset: Int64; Origin: TSeekOrigin): Int64; |
389 |
< |
begin |
390 |
< |
EnsureBlobInitialized; |
391 |
< |
case Origin of |
392 |
< |
soBeginning : FPosition := Offset; |
393 |
< |
soCurrent : Inc(FPosition, Offset); |
394 |
< |
soEnd : FPosition := FBlobSize + Offset; |
395 |
< |
end; |
396 |
< |
result := FPosition; |
397 |
< |
end; |
398 |
< |
|
399 |
< |
procedure TIBBlobStream.SetBlobID(Value: TISC_QUAD); |
400 |
< |
begin |
401 |
< |
System.Move(Value, FBlobID, SizeOf(TISC_QUAD)); |
402 |
< |
FBlobInitialized := False; |
403 |
< |
end; |
404 |
< |
|
405 |
< |
procedure TIBBlobStream.SetDatabase(Value: TIBDatabase); |
406 |
< |
begin |
407 |
< |
FBase.Database := Value; |
408 |
< |
FBlobInitialized := False; |
409 |
< |
end; |
410 |
< |
|
411 |
< |
procedure TIBBlobStream.SetMode(Value: TBlobStreamMode); |
412 |
< |
begin |
413 |
< |
FMode := Value; |
414 |
< |
FBlobInitialized := False; |
415 |
< |
end; |
416 |
< |
|
417 |
< |
procedure TIBBlobStream.SetSize(const NewSize: Int64); |
418 |
< |
begin |
419 |
< |
if (NewSize <> FBlobSize) then |
420 |
< |
begin |
421 |
< |
ReallocMem(FBuffer, NewSize); |
422 |
< |
FBlobSize := NewSize; |
423 |
< |
if NewSize = 0 then |
424 |
< |
FBuffer := nil; |
425 |
< |
end; |
426 |
< |
end; |
427 |
< |
|
428 |
< |
procedure TIBBlobStream.SetSize(NewSize: Longint); |
429 |
< |
begin |
430 |
< |
SetSize(Int64(NewSize)); |
431 |
< |
end; |
432 |
< |
|
433 |
< |
procedure TIBBlobStream.SetTransaction(Value: TIBTransaction); |
434 |
< |
begin |
435 |
< |
FBase.Transaction := Value; |
436 |
< |
FBlobInitialized := False; |
437 |
< |
end; |
438 |
< |
|
439 |
< |
procedure TIBBlobStream.Truncate; |
440 |
< |
begin |
441 |
< |
SetSize(0); |
442 |
< |
end; |
443 |
< |
|
444 |
< |
function TIBBlobStream.Write(const Buffer; Count: Longint): Longint; |
445 |
< |
begin |
446 |
< |
CheckWritable; |
447 |
< |
EnsureBlobInitialized; |
448 |
< |
result := Count; |
449 |
< |
if Count <= 0 then |
450 |
< |
exit; |
451 |
< |
if (FPosition + Count > FBlobSize) then |
452 |
< |
SetSize(FPosition + Count); |
453 |
< |
Move(Buffer, FBuffer[FPosition], Count); |
454 |
< |
Inc(FPosition, Count); |
455 |
< |
FModified := True; |
456 |
< |
end; |
457 |
< |
|
458 |
< |
end. |
1 |
> |
{************************************************************************} |
2 |
> |
{ } |
3 |
> |
{ Borland Delphi Visual Component Library } |
4 |
> |
{ InterBase Express core components } |
5 |
> |
{ } |
6 |
> |
{ Copyright (c) 1998-2000 Inprise Corporation } |
7 |
> |
{ } |
8 |
> |
{ InterBase Express is based in part on the product } |
9 |
> |
{ Free IB Components, written by Gregory H. Deatz for } |
10 |
> |
{ Hoagland, Longo, Moran, Dunst & Doukas Company. } |
11 |
> |
{ Free IB Components is used under license. } |
12 |
> |
{ } |
13 |
> |
{ The contents of this file are subject to the InterBase } |
14 |
> |
{ Public License Version 1.0 (the "License"); you may not } |
15 |
> |
{ use this file except in compliance with the License. You } |
16 |
> |
{ may obtain a copy of the License at http://www.Inprise.com/IPL.html } |
17 |
> |
{ Software distributed under the License is distributed on } |
18 |
> |
{ an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND, either } |
19 |
> |
{ express or implied. See the License for the specific language } |
20 |
> |
{ governing rights and limitations under the License. } |
21 |
> |
{ The Original Code was created by InterBase Software Corporation } |
22 |
> |
{ and its successors. } |
23 |
> |
{ Portions created by Inprise Corporation are Copyright (C) Inprise } |
24 |
> |
{ Corporation. All Rights Reserved. } |
25 |
> |
{ Contributor(s): Jeff Overcash } |
26 |
> |
{ } |
27 |
> |
{ IBX For Lazarus (Firebird Express) } |
28 |
> |
{ Contributor: Tony Whyman, MWA Software http://www.mwasoftware.co.uk } |
29 |
> |
{ Portions created by MWA Software are copyright McCallum Whyman } |
30 |
> |
{ Associates Ltd 2011 } |
31 |
> |
{************************************************************************} |
32 |
> |
|
33 |
> |
unit IBBlob; |
34 |
> |
|
35 |
> |
{$mode Delphi} |
36 |
> |
|
37 |
> |
interface |
38 |
> |
|
39 |
> |
uses |
40 |
> |
SysUtils, Classes, DB, IB, IBDatabase; |
41 |
> |
|
42 |
> |
|
43 |
> |
const |
44 |
> |
DefaultBlobSegmentSize = 16 * 1024; |
45 |
> |
|
46 |
> |
type |
47 |
> |
TIBBlobStates = (bsUninitialised, bsDataPending, bsData, bsModified); |
48 |
> |
|
49 |
> |
{ TIBBlobStream } |
50 |
> |
TIBBlobStream = class(TStream) |
51 |
> |
private |
52 |
> |
FBase: TIBBase; |
53 |
> |
FBlob: IBlob; |
54 |
> |
FBlobMaxSegmentSize: Int64; |
55 |
> |
FBlobNumSegments: Int64; |
56 |
> |
FBlobSize: Int64; |
57 |
> |
FBlobType: TBlobType; |
58 |
> |
FBuffer: PChar; |
59 |
> |
FColumnName: string; |
60 |
> |
FMode: TBlobStreamMode; |
61 |
> |
FPosition: Int64; |
62 |
> |
FBlobState: TIBBlobStates; |
63 |
> |
FRelationName: string; |
64 |
> |
function GetBlobID: TISC_QUAD; |
65 |
> |
function GetModified: Boolean; |
66 |
> |
procedure CheckActive; |
67 |
> |
protected |
68 |
> |
procedure CloseBlob; |
69 |
> |
procedure EnsureBlobInitialized; |
70 |
> |
procedure EnsureLoaded; |
71 |
> |
procedure GetBlobInfo; |
72 |
> |
function GetSize: Int64; override; |
73 |
> |
function GetDatabase: TIBDatabase; |
74 |
> |
function GetTransaction: TIBTransaction; |
75 |
> |
procedure OpenBlob; |
76 |
> |
procedure SetBlobID(Value: TISC_QUAD); |
77 |
> |
procedure SetDatabase(Value: TIBDatabase); |
78 |
> |
procedure SetMode(Value: TBlobStreamMode); |
79 |
> |
procedure SetState(aValue: TIBBlobStates); |
80 |
> |
procedure SetTransaction(Value: TIBTransaction); |
81 |
> |
public |
82 |
> |
constructor Create; |
83 |
> |
destructor Destroy; override; |
84 |
> |
procedure CheckReadable; |
85 |
> |
procedure CheckWritable; |
86 |
> |
procedure Finalize; |
87 |
> |
procedure LoadFromFile(Filename: string); |
88 |
> |
procedure LoadFromStream(Stream: TStream); |
89 |
> |
function Read(var Buffer; Count: Longint): Longint; override; |
90 |
> |
procedure SaveToFile(Filename: string); |
91 |
> |
procedure SaveToStream(Stream: TStream); |
92 |
> |
function Seek(const Offset: Int64; Origin: TSeekOrigin): Int64; override; |
93 |
> |
procedure SetField(aField: TField); |
94 |
> |
procedure SetSize(const NewSize: Int64); override; |
95 |
> |
procedure SetSize(NewSize: Longint); override; |
96 |
> |
procedure Truncate; |
97 |
> |
function Write(const Buffer; Count: Longint): Longint; override; |
98 |
> |
property BlobID: TISC_QUAD read GetBlobID write SetBlobID; |
99 |
> |
property Blob: IBlob read FBlob; |
100 |
> |
property BlobMaxSegmentSize: Int64 read FBlobMaxSegmentSize; |
101 |
> |
property BlobNumSegments: Int64 read FBlobNumSegments; |
102 |
> |
property BlobSize: Int64 read GetSize; |
103 |
> |
property BlobType: TBlobType read FBlobType; |
104 |
> |
property Database: TIBDatabase read GetDatabase write SetDatabase; |
105 |
> |
property Mode: TBlobStreamMode read FMode write SetMode; |
106 |
> |
property Modified: Boolean read GetModified; |
107 |
> |
property Transaction: TIBTransaction read GetTransaction write SetTransaction; |
108 |
> |
property RelationName: string read FRelationName; |
109 |
> |
property ColumnName: string read FColumnName; |
110 |
> |
end; |
111 |
> |
|
112 |
> |
implementation |
113 |
> |
|
114 |
> |
uses FBMessages, IBCustomDataSet; |
115 |
> |
|
116 |
> |
{ TIBBlobStream } |
117 |
> |
constructor TIBBlobStream.Create; |
118 |
> |
begin |
119 |
> |
inherited Create; |
120 |
> |
FBase := TIBBase.Create(Self); |
121 |
> |
FBuffer := nil; |
122 |
> |
FBlobSize := 0; |
123 |
> |
FBlobState := bsUninitialised; |
124 |
> |
FBlob := nil; |
125 |
> |
end; |
126 |
> |
|
127 |
> |
destructor TIBBlobStream.Destroy; |
128 |
> |
begin |
129 |
> |
CloseBlob; |
130 |
> |
FBase.Free; |
131 |
> |
SetSize(0); |
132 |
> |
inherited Destroy; |
133 |
> |
end; |
134 |
> |
|
135 |
> |
procedure TIBBlobStream.CheckReadable; |
136 |
> |
begin |
137 |
> |
if FMode = bmWrite then IBError(ibxeBlobCannotBeRead, [nil]); |
138 |
> |
end; |
139 |
> |
|
140 |
> |
procedure TIBBlobStream.CheckWritable; |
141 |
> |
begin |
142 |
> |
if FMode = bmRead then IBError(ibxeBlobCannotBeWritten, [nil]); |
143 |
> |
end; |
144 |
> |
|
145 |
> |
function TIBBlobStream.GetModified: Boolean; |
146 |
> |
begin |
147 |
> |
Result := FBlobState = bsModified; |
148 |
> |
end; |
149 |
> |
|
150 |
> |
procedure TIBBlobStream.CheckActive; |
151 |
> |
begin |
152 |
> |
if Database = nil then |
153 |
> |
IBError(ibxeDatabaseNotAssigned,[nil]); |
154 |
> |
|
155 |
> |
if (Database.Attachment = nil) or |
156 |
> |
not Database.Attachment.IsConnected then |
157 |
> |
IBError(ibxeDatabaseClosed,[nil]); |
158 |
> |
|
159 |
> |
if Transaction = nil then |
160 |
> |
IBError(ibxeTransactionNotAssigned,[nil]); |
161 |
> |
|
162 |
> |
if (Transaction.TransactionIntf = nil) or |
163 |
> |
not Transaction.TransactionIntf.InTransaction then |
164 |
> |
IBError(ibxeNotInTransaction,[nil]); |
165 |
> |
end; |
166 |
> |
|
167 |
> |
function TIBBlobStream.GetBlobID: TISC_QUAD; |
168 |
> |
begin |
169 |
> |
if (FBlob = nil) or (FBlobSize = 0) then |
170 |
> |
begin |
171 |
> |
Result.gds_quad_high := 0; |
172 |
> |
Result.gds_quad_low := 0; |
173 |
> |
end |
174 |
> |
else |
175 |
> |
Result := FBlob.GetBlobID; |
176 |
> |
end; |
177 |
> |
|
178 |
> |
procedure TIBBlobStream.CloseBlob; |
179 |
> |
begin |
180 |
> |
Finalize; |
181 |
> |
FBlob := nil; |
182 |
> |
SetState(bsUninitialised); |
183 |
> |
end; |
184 |
> |
|
185 |
> |
procedure TIBBlobStream.EnsureBlobInitialized; |
186 |
> |
begin |
187 |
> |
if FBlobState <> bsUninitialised then Exit; |
188 |
> |
|
189 |
> |
if FMode = bmWrite then |
190 |
> |
SetState(bsData) |
191 |
> |
else |
192 |
> |
begin |
193 |
> |
CheckReadable; |
194 |
> |
if FBlob = nil then Exit; |
195 |
> |
try |
196 |
> |
GetBlobInfo; |
197 |
> |
{Defer reading in blob until read method called} |
198 |
> |
except |
199 |
> |
FBlob := nil; |
200 |
> |
raise; |
201 |
> |
end; |
202 |
> |
SetState(bsDataPending); |
203 |
> |
end; |
204 |
> |
end; |
205 |
> |
|
206 |
> |
procedure TIBBlobStream.EnsureLoaded; |
207 |
> |
begin |
208 |
> |
EnsureBlobInitialized; |
209 |
> |
if (FBlobState = bsDataPending) and (FBlob <> nil) then |
210 |
> |
begin |
211 |
> |
SetSize(FBlobSize); |
212 |
> |
FBlob.Read(FBuffer^, FBlobSize); |
213 |
> |
SetState(bsData); |
214 |
> |
end; |
215 |
> |
end; |
216 |
> |
|
217 |
> |
procedure TIBBlobStream.Finalize; |
218 |
> |
begin |
219 |
> |
if FBlobState <> bsModified then |
220 |
> |
exit; |
221 |
> |
CheckWritable; |
222 |
> |
if FBlobSize > 0 then |
223 |
> |
begin |
224 |
> |
{ need to start writing to a blob, create one } |
225 |
> |
FBlob := Database.Attachment.CreateBlob(Transaction.TransactionIntf,RelationName,ColumnName); |
226 |
> |
FBlob.Write(FBuffer^, FBlobSize); |
227 |
> |
FBlob.Close; |
228 |
> |
end; |
229 |
> |
SetState(bsData); |
230 |
> |
end; |
231 |
> |
|
232 |
> |
procedure TIBBlobStream.GetBlobInfo; |
233 |
> |
var |
234 |
> |
iBlobSize: Int64; |
235 |
> |
begin |
236 |
> |
if FBlob = nil then Exit; |
237 |
> |
|
238 |
> |
FBlob.GetInfo(FBlobNumSegments, FBlobMaxSegmentSize, iBlobSize, FBlobType); |
239 |
> |
SetSize(iBlobSize); |
240 |
> |
end; |
241 |
> |
|
242 |
> |
function TIBBlobStream.GetSize: Int64; |
243 |
> |
begin |
244 |
> |
EnsureBlobInitialized; |
245 |
> |
Result := FBlobSize; |
246 |
> |
end; |
247 |
> |
|
248 |
> |
function TIBBlobStream.GetDatabase: TIBDatabase; |
249 |
> |
begin |
250 |
> |
result := FBase.Database; |
251 |
> |
end; |
252 |
> |
|
253 |
> |
function TIBBlobStream.GetTransaction: TIBTransaction; |
254 |
> |
begin |
255 |
> |
result := FBase.Transaction; |
256 |
> |
end; |
257 |
> |
|
258 |
> |
procedure TIBBlobStream.LoadFromFile(Filename: string); |
259 |
> |
var |
260 |
> |
Stream: TStream; |
261 |
> |
begin |
262 |
> |
Stream := TFileStream.Create(FileName, fmOpenRead); |
263 |
> |
try |
264 |
> |
LoadFromStream(Stream); |
265 |
> |
finally |
266 |
> |
Stream.Free; |
267 |
> |
end; |
268 |
> |
end; |
269 |
> |
|
270 |
> |
procedure TIBBlobStream.LoadFromStream(Stream: TStream); |
271 |
> |
begin |
272 |
> |
CheckWritable; |
273 |
> |
EnsureBlobInitialized; |
274 |
> |
Stream.Position := 0; |
275 |
> |
SetSize(Stream.Size); |
276 |
> |
if FBlobSize <> 0 then |
277 |
> |
Stream.ReadBuffer(FBuffer^, FBlobSize); |
278 |
> |
SetState(bsModified); |
279 |
> |
end; |
280 |
> |
|
281 |
> |
procedure TIBBlobStream.OpenBlob; |
282 |
> |
begin |
283 |
> |
CheckReadable; |
284 |
> |
try |
285 |
> |
GetBlobInfo; |
286 |
> |
{Defer reading in blob until read method called} |
287 |
> |
except |
288 |
> |
FBlob.Close; |
289 |
> |
raise; |
290 |
> |
end; |
291 |
> |
SetState(bsDataPending); |
292 |
> |
end; |
293 |
> |
|
294 |
> |
function TIBBlobStream.Read(var Buffer; Count: Longint): Longint; |
295 |
> |
begin |
296 |
> |
CheckReadable; |
297 |
> |
EnsureLoaded; |
298 |
> |
if Count <= 0 then |
299 |
> |
begin |
300 |
> |
result := 0; |
301 |
> |
exit; |
302 |
> |
end; |
303 |
> |
if (FPosition + Count > FBlobSize) then |
304 |
> |
result := FBlobSize - FPosition |
305 |
> |
else |
306 |
> |
result := Count; |
307 |
> |
Move(FBuffer[FPosition], Buffer, result); |
308 |
> |
Inc(FPosition, Result); |
309 |
> |
end; |
310 |
> |
|
311 |
> |
procedure TIBBlobStream.SaveToFile(Filename: string); |
312 |
> |
var |
313 |
> |
Stream: TStream; |
314 |
> |
begin |
315 |
> |
Stream := TFileStream.Create(FileName, fmCreate); |
316 |
> |
try |
317 |
> |
SaveToStream(Stream); |
318 |
> |
finally |
319 |
> |
Stream.Free; |
320 |
> |
end; |
321 |
> |
end; |
322 |
> |
|
323 |
> |
procedure TIBBlobStream.SaveToStream(Stream: TStream); |
324 |
> |
begin |
325 |
> |
CheckReadable; |
326 |
> |
EnsureLoaded; |
327 |
> |
if FBlobSize <> 0 then |
328 |
> |
begin |
329 |
> |
Seek(0, soFromBeginning); |
330 |
> |
Stream.WriteBuffer(FBuffer^, FBlobSize); |
331 |
> |
end; |
332 |
> |
end; |
333 |
> |
|
334 |
> |
function TIBBlobStream.Seek(const Offset: Int64; Origin: TSeekOrigin): Int64; |
335 |
> |
begin |
336 |
> |
EnsureBlobInitialized; |
337 |
> |
case Origin of |
338 |
> |
soBeginning : FPosition := Offset; |
339 |
> |
soCurrent : Inc(FPosition, Offset); |
340 |
> |
soEnd : FPosition := FBlobSize + Offset; |
341 |
> |
end; |
342 |
> |
result := FPosition; |
343 |
> |
end; |
344 |
> |
|
345 |
> |
procedure TIBBlobStream.SetField(aField: TField); |
346 |
> |
begin |
347 |
> |
FRelationName := ''; |
348 |
> |
if aField.FieldDef <> nil then |
349 |
> |
FRelationName := (aField.FieldDef as TIBFieldDef).RelationName; |
350 |
> |
FColumnName := aField.FieldName;; |
351 |
> |
end; |
352 |
> |
|
353 |
> |
procedure TIBBlobStream.SetBlobID(Value: TISC_QUAD); |
354 |
> |
begin |
355 |
> |
CheckActive; |
356 |
> |
FBlob := nil; |
357 |
> |
if (Value.gds_quad_high = 0) and (Value.gds_quad_low = 0) then |
358 |
> |
Exit; |
359 |
> |
FBlob := Database.Attachment.OpenBlob(Transaction.TransactionIntf,RelationName,ColumnName,Value); |
360 |
> |
if FBlobState <> bsData then |
361 |
> |
SetState(bsUninitialised); |
362 |
> |
end; |
363 |
> |
|
364 |
> |
procedure TIBBlobStream.SetDatabase(Value: TIBDatabase); |
365 |
> |
begin |
366 |
> |
FBase.Database := Value; |
367 |
> |
SetState(bsUninitialised); |
368 |
> |
end; |
369 |
> |
|
370 |
> |
procedure TIBBlobStream.SetMode(Value: TBlobStreamMode); |
371 |
> |
begin |
372 |
> |
FMode := Value; |
373 |
> |
SetState(bsUninitialised); |
374 |
> |
end; |
375 |
> |
|
376 |
> |
procedure TIBBlobStream.SetState(aValue: TIBBlobStates); |
377 |
> |
begin |
378 |
> |
if FBlobState = aValue then Exit; |
379 |
> |
|
380 |
> |
if (FBlobState = bsDataPending) and (FBlob <> nil) then |
381 |
> |
FBlob.Close; |
382 |
> |
|
383 |
> |
FBlobState := aValue; |
384 |
> |
end; |
385 |
> |
|
386 |
> |
procedure TIBBlobStream.SetSize(const NewSize: Int64); |
387 |
> |
begin |
388 |
> |
if (NewSize <> FBlobSize) then |
389 |
> |
begin |
390 |
> |
ReallocMem(FBuffer, NewSize); |
391 |
> |
FBlobSize := NewSize; |
392 |
> |
if NewSize = 0 then |
393 |
> |
FBuffer := nil; |
394 |
> |
end; |
395 |
> |
end; |
396 |
> |
|
397 |
> |
procedure TIBBlobStream.SetSize(NewSize: Longint); |
398 |
> |
begin |
399 |
> |
SetSize(Int64(NewSize)); |
400 |
> |
end; |
401 |
> |
|
402 |
> |
procedure TIBBlobStream.SetTransaction(Value: TIBTransaction); |
403 |
> |
begin |
404 |
> |
FBase.Transaction := Value; |
405 |
> |
SetState(bsUninitialised); |
406 |
> |
end; |
407 |
> |
|
408 |
> |
procedure TIBBlobStream.Truncate; |
409 |
> |
begin |
410 |
> |
SetSize(0); |
411 |
> |
SetState(bsModified); |
412 |
> |
end; |
413 |
> |
|
414 |
> |
function TIBBlobStream.Write(const Buffer; Count: Longint): Longint; |
415 |
> |
begin |
416 |
> |
CheckWritable; |
417 |
> |
EnsureLoaded; {Could be an untruncated bmReadWrite Blob} |
418 |
> |
result := Count; |
419 |
> |
if Count <= 0 then |
420 |
> |
exit; |
421 |
> |
if (FPosition + Count > FBlobSize) then |
422 |
> |
SetSize(FPosition + Count); |
423 |
> |
Move(Buffer, FBuffer[FPosition], Count); |
424 |
> |
Inc(FPosition, Count); |
425 |
> |
SetState(bsModified); |
426 |
> |
end; |
427 |
> |
|
428 |
> |
end. |