Get rid of a global variable

bootstrap_data_checksum_version can just as easily be passed to where
it is used via function arguments.

Reviewed-by: Andres Freund <andres@anarazel.de>
Discussion: https://www.postgresql.org/message-id/flat/e0a62134-83da-4ba4-8cdb-ceb0111c95ce@eisentraut.org

src/backend/access/transam/xlog.c

@@ -105,8 +105,6 @@
 #include "utils/timestamp.h"
 #include "utils/varlena.h"
 
-extern uint32 bootstrap_data_checksum_version;
-
 /* timeline ID to be used when bootstrapping */
 #define BootstrapTimeLineID		1
 
@@ -683,7 +681,7 @@ static void ValidateXLOGDirectoryStructure(void);
 static void CleanupBackupHistory(void);
 static void UpdateMinRecoveryPoint(XLogRecPtr lsn, bool force);
 static bool PerformRecoveryXLogAction(void);
-static void InitControlFile(uint64 sysidentifier);
+static void InitControlFile(uint64 sysidentifier, uint32 data_checksum_version);
 static void WriteControlFile(void);
 static void ReadControlFile(void);
 static void UpdateControlFile(void);
@@ -4190,7 +4188,7 @@ CleanupBackupHistory(void)
  */
 
 static void
-InitControlFile(uint64 sysidentifier)
+InitControlFile(uint64 sysidentifier, uint32 data_checksum_version)
 {
 	char		mock_auth_nonce[MOCK_AUTH_NONCE_LEN];
 
@@ -4221,7 +4219,7 @@ InitControlFile(uint64 sysidentifier)
 	ControlFile->wal_level = wal_level;
 	ControlFile->wal_log_hints = wal_log_hints;
 	ControlFile->track_commit_timestamp = track_commit_timestamp;
-	ControlFile->data_checksum_version = bootstrap_data_checksum_version;
+	ControlFile->data_checksum_version = data_checksum_version;
 }
 
 static void
@@ -4997,7 +4995,7 @@ XLOGShmemInit(void)
  * and the initial XLOG segment.
  */
 void
-BootStrapXLOG(void)
+BootStrapXLOG(uint32 data_checksum_version)
 {
 	CheckPoint	checkPoint;
 	char	   *buffer;
@@ -5139,7 +5137,7 @@ BootStrapXLOG(void)
 	openLogFile = -1;
 
 	/* Now create pg_control */
-	InitControlFile(sysidentifier);
+	InitControlFile(sysidentifier, data_checksum_version);
 	ControlFile->time = checkPoint.time;
 	ControlFile->checkPoint = checkPoint.redo;
 	ControlFile->checkPointCopy = checkPoint;

src/backend/bootstrap/bootstrap.c

@@ -41,8 +41,6 @@
 #include "utils/rel.h"
 #include "utils/relmapper.h"
 
-uint32		bootstrap_data_checksum_version = 0;	/* No checksum */
-
 
 static void CheckerModeMain(void);
 static void bootstrap_signals(void);
@@ -202,6 +200,7 @@ BootstrapModeMain(int argc, char *argv[], bool check_only)
 	char	   *progname = argv[0];
 	int			flag;
 	char	   *userDoption = NULL;
+	uint32		bootstrap_data_checksum_version = 0;	/* No checksum */
 
 	Assert(!IsUnderPostmaster);
 
@@ -332,7 +331,7 @@ BootstrapModeMain(int argc, char *argv[], bool check_only)
 	BaseInit();
 
 	bootstrap_signals();
-	BootStrapXLOG();
+	BootStrapXLOG(bootstrap_data_checksum_version);
 
 	/*
 	 * To ensure that src/common/link-canary.c is linked into the backend, we

src/include/access/xlog.h

@@ -231,7 +231,7 @@ extern bool DataChecksumsEnabled(void);
 extern XLogRecPtr GetFakeLSNForUnloggedRel(void);
 extern Size XLOGShmemSize(void);
 extern void XLOGShmemInit(void);
-extern void BootStrapXLOG(void);
+extern void BootStrapXLOG(uint32 data_checksum_version);
 extern void InitializeWalConsistencyChecking(void);
 extern void LocalProcessControlFile(bool reset);
 extern WalLevel GetActiveWalLevelOnStandby(void);