/*
* PROGRAM: Object oriented API samples.
* MODULE: 07.blob.cpp
* DESCRIPTION: A sample of loading data into blob and reading.
* Run second time (when database already exists) to see
* how FbException is caught and handled by this code.
*
* Example for the following interfaces:
* IAttachment - use of open and create blob methods
* IBlob - interface to work with blobs
*
* The 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 at
* http://www.ibphoenix.com/main.nfs?a=ibphoenix&page=ibp_idpl.
*
* Software distributed under the License is distributed AS IS,
* 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 Alexander Peshkoff
* for the Firebird Open Source RDBMS project.
*
* Copyright (c) 2016 Alexander Peshkoff <peshkoff@mail.ru>
* and all contributors signed below.
*
* All Rights Reserved.
* Contributor(s): ______________________________________.
*/
#include "ifaceExamples.h"
#include <firebird/Message.h>
static IMaster* master = fb_get_master_interface();
static const char* testData[] = {
"This is test data",
"that is inserted during example execution",
"into blobs_table",
NULL
};
static void errPrint(IStatus* status)
{
char buf[256];
master->getUtilInterface()->formatStatus(buf, sizeof(buf), status);
fprintf(stderr, "%s\n", buf);
}
static void drop(IAttachment** att)
{
// With CheckStatusWrapper passed as status interface noting is thrown on error
// You should check status yourself
CheckStatusWrapper status(master->getStatus());
// drop database (will close interface)
(*att)->dropDatabase(&status);
if (status.getState() & IStatus::STATE_ERRORS)
{
errPrint(&status);
fprintf(stderr, "*** Drop database failed - do it manually before next run ***\n");
}
else
*att = NULL;
// cleanup
status.dispose();
}
int main()
{
int rc = 0;
// set default password if none specified in environment
setenv("ISC_USER", "sysdba", 0);
setenv("ISC_PASSWORD", "masterkey", 0);
// With ThrowStatusWrapper passed as status interface FbException will be thrown on error
ThrowStatusWrapper status(master->getStatus());
// Declare pointers to required interfaces
IProvider* prov = master->getDispatcher();
IAttachment* att = NULL;
ITransaction* tra = NULL;
IBlob* blob = NULL;
try
{
// create database
att = prov->createDatabase(&status, "blob_07.fdb", 0, NULL);
tra = att->startTransaction(&status, 0, NULL);
// create table
att->execute(&status, tra, 0, "create table blobs_table (b blob sub_type text)", SAMPLES_DIALECT,
NULL, NULL, NULL, NULL);
tra->commitRetaining(&status);
// Message for data exchange
FB_MESSAGE(Msg, ThrowStatusWrapper,
(FB_BLOB, b)
) message(&status, master);
message.clear();
// create blob
blob = att->createBlob(&status, tra, &message->b, 0, NULL);
// populate blob with data
for (const char** seg = testData; *seg; ++seg)
blob->putSegment(&status, strlen(*seg), *seg);
blob->close(&status);
blob = NULL;
// insert blob into the table
att->execute(&status, tra, 0, "insert into blobs_table(b) values(?)", SAMPLES_DIALECT,
message.getMetadata(), message.getData(), NULL, NULL);
tra->commitRetaining(&status);
printf("Test blob inserted into blobs_table\n...\n");
// Read blob from table
message.clear();
att->execute(&status, tra, 0, "select first(1) b from blobs_table", SAMPLES_DIALECT,
NULL, NULL, message.getMetadata(), message.getData());
blob = att->openBlob(&status, tra, &message->b, 0, NULL);
// Read segments from blob
// Use very small segment buffer to show read of incomplete segment
printf("Read inserted blob from blobs_table\n...\n");
int bufOver = 0;
for(bool eof = false; !eof; )
{
const char* lineFeed = "\n";
char buf[32];
unsigned l = 0;
switch (blob->getSegment(&status, sizeof(buf) - 1, buf, &l))
{
case IStatus::RESULT_OK:
break;
case IStatus::RESULT_SEGMENT:
lineFeed = "";
bufOver++;
break;
default:
eof = true;
continue;
}
buf[l] = 0;
printf("%s%s", buf, lineFeed);
}
printf("\nSegment not fit in buffer counter = %d\n\n", bufOver);
// cleanup
blob->close(&status);
blob = NULL;
tra->commit(&status);
tra = NULL;
// uncomment next line to play with errors during drop database
// printf("Attach with any client to blob_07.fdb to prevent it being dropped and press enter"); getchar();
// drop database
drop(&att);
}
catch (const FbException& error)
{
// handle error
rc = 1;
errPrint(error.getStatus());
if (att)
drop(&att);
}
// release interfaces after error caught
if (blob)
blob->release();
if (tra)
tra->release();
if (att)
att->release();
status.dispose();
prov->release();
return rc;
}