pg_restore: fix incompatibility with old directory-format dumps.

tglsfdc · tglsfdc · commit 166b4f4560d6 · 2025-06-08T17:06:39.000-04:00
pg_restore failed to restore large objects (blobs) out of directory-format dumps made by versions before PG v12. That's because, due to a bug fixed in commit 548e509, those old versions put the wrong filename into the BLOBS TOC entry. Said bug was harmless before v17, because we ignored the incorrect filename field --- but commit a45c78e assumed it would be correct. Reported-by: Pavel Stehule <pavel.stehule@gmail.com> Author: Pavel Stehule <pavel.stehule@gmail.com> Reviewed-by: Tom Lane <tgl@sss.pgh.pa.us> Discussion: https://postgr.es/m/CAFj8pRCrZ=_e1Rv1N+6vDaH+6gf=9A2mE2J4RvnvKA1bLiXvXA@mail.gmail.com Backpatch-through: 17
diff --git a/src/bin/pg_dump/pg_backup_directory.c b/src/bin/pg_dump/pg_backup_directory.c
@@ -412,10 +412,15 @@ _LoadLOs(ArchiveHandle *AH, TocEntry *te)
 
 	/*
 	 * Note: before archive v16, there was always only one BLOBS TOC entry,
-	 * now there can be multiple.  We don't need to worry what version we are
-	 * reading though, because tctx->filename should be correct either way.
+	 * now there can be multiple.  Furthermore, although the actual filename
+	 * was always "blobs.toc" before v16, the value of tctx->filename did not
+	 * match that before commit 548e50976 fixed it.  For simplicity we assume
+	 * it must be "blobs.toc" in all archives before v16.
 	 */
-	setFilePath(AH, tocfname, tctx->filename);
+	if (AH->version < K_VERS_1_16)
+		setFilePath(AH, tocfname, "blobs.toc");
+	else
+		setFilePath(AH, tocfname, tctx->filename);
 
 	CFH = ctx->LOsTocFH = InitDiscoverCompressFileHandle(tocfname, PG_BINARY_R);
 
