void
DropBlobIfExists(ArchiveHandle *AH, Oid oid)
{
/*
* If we are not restoring to a direct database connection, we have to
* guess about how to detect whether the blob exists. Assume new-style.
*/
if (AH->connection == NULL ||
PQserverVersion(AH->connection) >= 90000)
{
ahprintf(AH,
"SELECT pg_catalog.lo_unlink(oid) "
"FROM pg_catalog.pg_largeobject_metadata "
"WHERE oid = '%u';\n",
oid);
}
else
{
/* Restoring to pre-9.0 server, so do it the old way */
ahprintf(AH,
"SELECT CASE WHEN EXISTS("
"SELECT 1 FROM pg_catalog.pg_largeobject WHERE loid = '%u'"
") THEN pg_catalog.lo_unlink('%u') END;\n",
oid, oid);
}
}
static void
_PrintExtraToc(ArchiveHandle *AH, TocEntry *te)
{
lclTocEntry *ctx = (lclTocEntry *) te->formatData;
ahprintf(AH, "-- File: %s\n", ctx->filename);
}
/*
* Called by the archiver when the dumper calls EndBlob.
*
* Optional.
*/
static void
_EndBlob(ArchiveHandle *AH, TocEntry *te, Oid oid)
{
AH->WriteDataPtr = _WriteData;
ahprintf(AH, "SELECT lo_close(0);\n\n");
}
/*
* Called by the archiver when the dumper calls StartBlob.
*
* Mandatory.
*
* Must save the passed OID for retrieval at restore-time.
*/
static void
_StartBlob(ArchiveHandle *AH, TocEntry *te, Oid oid)
{
if (oid == 0)
die_horribly(AH, NULL, "invalid OID for large object\n");
ahprintf(AH, "SELECT lo_open(lo_create(%u), %d);\n", oid, INV_WRITE);
AH->WriteDataPtr = _WriteBlobData;
}
/*
* Called by the archiver when the dumper calls StartBlob.
*
* Mandatory.
*
* Must save the passed OID for retrieval at restore-time.
*/
static void
_StartBlob(ArchiveHandle *AH, TocEntry *te, Oid oid)
{
bool old_blob_style = (AH->version < K_VERS_1_12);
if (oid == 0)
die_horribly(AH, NULL, "invalid OID for large object\n");
/* With an old archive we must do drop and create logic here */
if (old_blob_style && AH->ropt->dropSchema)
DropBlobIfExists(AH, oid);
if (old_blob_style)
ahprintf(AH, "SELECT pg_catalog.lo_open(pg_catalog.lo_create('%u'), %d);\n",
oid, INV_WRITE);
else
ahprintf(AH, "SELECT pg_catalog.lo_open('%u', %d);\n",
oid, INV_WRITE);
AH->WriteDataPtr = _WriteBlobData;
}
/*
* Called by dumper via archiver from within a data dump routine
* We substitute this for _WriteData while emitting a BLOB
*/
static size_t
_WriteBlobData(ArchiveHandle *AH, const void *data, size_t dLen)
{
if (dLen > 0)
{
PQExpBuffer buf = createPQExpBuffer();
appendByteaLiteralAHX(buf,
(const unsigned char *) data,
dLen,
AH);
ahprintf(AH, "SELECT pg_catalog.lowrite(0, %s);\n", buf->data);
destroyPQExpBuffer(buf);
}
return dLen;
}
static void
_EndData(ArchiveHandle *AH, TocEntry *te)
{
ahprintf(AH, "\n\n");
}
/*
* Called by the archiver when finishing saving all BLOB DATA.
*
* Optional.
*/
static void
_EndBlobs(ArchiveHandle *AH, TocEntry *te)
{
ahprintf(AH, "COMMIT;\n\n");
}
/*
* Called by the archiver when starting to save all BLOB DATA (not schema).
* This routine should save whatever format-specific information is needed
* to read the BLOBs back into memory.
*
* It is called just prior to the dumper's DataDumper routine.
*
* Optional, but strongly recommended.
*/
static void
_StartBlobs(ArchiveHandle *AH, TocEntry *te)
{
ahprintf(AH, "BEGIN;\n\n");
}
