Clean up some residual confusion between OIDs and RelFileNumbers.

Commit b0a55e4329 missed a few places
where we are referring to the number used as a part of the relation
filename as an "OID". We now want to call that a "RelFileNumber".

Some of these places actually made it sound like the OID in question
is pg_class.oid rather than pg_class.relfilenode, which is especially
good to clean up.

Dilip Kumar with some editing by me.

src/backend/commands/dbcommands.c

@@ -254,7 +254,7 @@ ScanSourceDatabasePgClass(Oid tbid, Oid dbid, char *srcpath)
 	BlockNumber nblocks;
 	BlockNumber blkno;
 	Buffer		buf;
-	Oid			relfilenumber;
+	RelFileNumber relfilenumber;
 	Page		page;
 	List	   *rlocatorlist = NIL;
 	LockRelId	relid;
@@ -401,7 +401,7 @@ ScanSourceDatabasePgClassTuple(HeapTupleData *tuple, Oid tbid, Oid dbid,
 {
 	CreateDBRelInfo *relinfo;
 	Form_pg_class classForm;
-	Oid			relfilenumber = InvalidRelFileNumber;
+	RelFileNumber relfilenumber = InvalidRelFileNumber;
 
 	classForm = (Form_pg_class) GETSTRUCT(tuple);
 

src/backend/replication/basebackup.c

@@ -1172,7 +1172,8 @@ sendDir(bbsink *sink, const char *path, int basepathlen, bool sizeonly,
 		int			excludeIdx;
 		bool		excludeFound;
 		ForkNumber	relForkNum; /* Type of fork if file is a relation */
-		int			relOidChars;	/* Chars in filename that are the rel oid */
+		int			relnumchars;	/* Chars in filename that are the
+									 * relnumber */
 
 		/* Skip special stuff */
 		if (strcmp(de->d_name, ".") == 0 || strcmp(de->d_name, "..") == 0)
@@ -1222,23 +1223,24 @@ sendDir(bbsink *sink, const char *path, int basepathlen, bool sizeonly,
 
 		/* Exclude all forks for unlogged tables except the init fork */
 		if (isDbDir &&
-			parse_filename_for_nontemp_relation(de->d_name, &relOidChars,
+			parse_filename_for_nontemp_relation(de->d_name, &relnumchars,
 												&relForkNum))
 		{
 			/* Never exclude init forks */
 			if (relForkNum != INIT_FORKNUM)
 			{
 				char		initForkFile[MAXPGPATH];
-				char		relOid[OIDCHARS + 1];
+				char		relNumber[OIDCHARS + 1];
 
 				/*
 				 * If any other type of fork, check if there is an init fork
-				 * with the same OID. If so, the file can be excluded.
+				 * with the same RelFileNumber. If so, the file can be
+				 * excluded.
 				 */
-				memcpy(relOid, de->d_name, relOidChars);
+				memcpy(relNumber, de->d_name, relnumchars);
-				relOid[relOidChars] = '\0';
+				relNumber[relnumchars] = '\0';
 				snprintf(initForkFile, sizeof(initForkFile), "%s/%s_init",
-						 path, relOid);
+						 path, relNumber);
 
 				if (lstat(initForkFile, &statbuf) == 0)
 				{

src/backend/storage/file/reinit.c

@@ -195,11 +195,11 @@ ResetUnloggedRelationsInDbspaceDir(const char *dbspacedirname, int op)
 		while ((de = ReadDir(dbspace_dir, dbspacedirname)) != NULL)
 		{
 			ForkNumber	forkNum;
-			int			oidchars;
+			int			relnumchars;
 			unlogged_relation_entry ent;
 
 			/* Skip anything that doesn't look like a relation data file. */
-			if (!parse_filename_for_nontemp_relation(de->d_name, &oidchars,
+			if (!parse_filename_for_nontemp_relation(de->d_name, &relnumchars,
 													 &forkNum))
 				continue;
 
@@ -235,11 +235,11 @@ ResetUnloggedRelationsInDbspaceDir(const char *dbspacedirname, int op)
 		while ((de = ReadDir(dbspace_dir, dbspacedirname)) != NULL)
 		{
 			ForkNumber	forkNum;
-			int			oidchars;
+			int			relnumchars;
 			unlogged_relation_entry ent;
 
 			/* Skip anything that doesn't look like a relation data file. */
-			if (!parse_filename_for_nontemp_relation(de->d_name, &oidchars,
+			if (!parse_filename_for_nontemp_relation(de->d_name, &relnumchars,
 													 &forkNum))
 				continue;
 
@@ -285,13 +285,13 @@ ResetUnloggedRelationsInDbspaceDir(const char *dbspacedirname, int op)
 		while ((de = ReadDir(dbspace_dir, dbspacedirname)) != NULL)
 		{
 			ForkNumber	forkNum;
-			int			oidchars;
+			int			relnumchars;
-			char		oidbuf[OIDCHARS + 1];
+			char		relnumbuf[OIDCHARS + 1];
 			char		srcpath[MAXPGPATH * 2];
 			char		dstpath[MAXPGPATH];
 
 			/* Skip anything that doesn't look like a relation data file. */
-			if (!parse_filename_for_nontemp_relation(de->d_name, &oidchars,
+			if (!parse_filename_for_nontemp_relation(de->d_name, &relnumchars,
 													 &forkNum))
 				continue;
 
@@ -304,10 +304,10 @@ ResetUnloggedRelationsInDbspaceDir(const char *dbspacedirname, int op)
 					 dbspacedirname, de->d_name);
 
 			/* Construct destination pathname. */
-			memcpy(oidbuf, de->d_name, oidchars);
+			memcpy(relnumbuf, de->d_name, relnumchars);
-			oidbuf[oidchars] = '\0';
+			relnumbuf[relnumchars] = '\0';
 			snprintf(dstpath, sizeof(dstpath), "%s/%s%s",
-					 dbspacedirname, oidbuf, de->d_name + oidchars + 1 +
+					 dbspacedirname, relnumbuf, de->d_name + relnumchars + 1 +
 					 strlen(forkNames[INIT_FORKNUM]));
 
 			/* OK, we're ready to perform the actual copy. */
@@ -328,12 +328,12 @@ ResetUnloggedRelationsInDbspaceDir(const char *dbspacedirname, int op)
 		while ((de = ReadDir(dbspace_dir, dbspacedirname)) != NULL)
 		{
 			ForkNumber	forkNum;
-			int			oidchars;
+			int			relnumchars;
-			char		oidbuf[OIDCHARS + 1];
+			char		relnumbuf[OIDCHARS + 1];
 			char		mainpath[MAXPGPATH];
 
 			/* Skip anything that doesn't look like a relation data file. */
-			if (!parse_filename_for_nontemp_relation(de->d_name, &oidchars,
+			if (!parse_filename_for_nontemp_relation(de->d_name, &relnumchars,
 													 &forkNum))
 				continue;
 
@@ -342,10 +342,10 @@ ResetUnloggedRelationsInDbspaceDir(const char *dbspacedirname, int op)
 				continue;
 
 			/* Construct main fork pathname. */
-			memcpy(oidbuf, de->d_name, oidchars);
+			memcpy(relnumbuf, de->d_name, relnumchars);
-			oidbuf[oidchars] = '\0';
+			relnumbuf[relnumchars] = '\0';
 			snprintf(mainpath, sizeof(mainpath), "%s/%s%s",
-					 dbspacedirname, oidbuf, de->d_name + oidchars + 1 +
+					 dbspacedirname, relnumbuf, de->d_name + relnumchars + 1 +
 					 strlen(forkNames[INIT_FORKNUM]));
 
 			fsync_fname(mainpath, false);
@@ -372,13 +372,13 @@ ResetUnloggedRelationsInDbspaceDir(const char *dbspacedirname, int op)
  * for a non-temporary relation and false otherwise.
  *
  * NB: If this function returns true, the caller is entitled to assume that
- * *oidchars has been set to the a value no more than OIDCHARS, and thus
+ * *relnumchars has been set to a value no more than OIDCHARS, and thus
- * that a buffer of OIDCHARS+1 characters is sufficient to hold the OID
+ * that a buffer of OIDCHARS+1 characters is sufficient to hold the
- * portion of the filename.  This is critical to protect against a possible
+ * RelFileNumber portion of the filename.  This is critical to protect against
- * buffer overrun.
+ * a possible buffer overrun.
  */
 bool
-parse_filename_for_nontemp_relation(const char *name, int *oidchars,
+parse_filename_for_nontemp_relation(const char *name, int *relnumchars,
 									ForkNumber *fork)
 {
 	int			pos;
@@ -388,7 +388,7 @@ parse_filename_for_nontemp_relation(const char *name, int *oidchars,
 		;
 	if (pos == 0 || pos > OIDCHARS)
 		return false;
-	*oidchars = pos;
+	*relnumchars = pos;
 
 	/* Check for a fork name. */
 	if (name[pos] != '_')

src/include/storage/reinit.h

@@ -20,7 +20,8 @@
 
 extern void ResetUnloggedRelations(int op);
 extern bool parse_filename_for_nontemp_relation(const char *name,
-												int *oidchars, ForkNumber *fork);
+												int *relnumchars,
+												ForkNumber *fork);
 
 #define UNLOGGED_RELATION_CLEANUP		0x0001
 #define UNLOGGED_RELATION_INIT			0x0002