Re: TODO: Split out pg_resetxlog output into pre- and post-sections

*** a/doc/src/sgml/ref/pg_resetxlog.sgml
--- b/doc/src/sgml/ref/pg_resetxlog.sgml
***************
*** 180,185 **** PostgreSQL documentation
--- 180,189 ----
     <filename>pg_control</> and then exit without modifying anything.
     This is mainly a debugging tool, but can be useful as a sanity check
     before allowing <command>pg_resetxlog</command> to proceed for real.
+    It will print values in two sections. In first section it will print all original/guessed values
+    and in second section all values to be used after reset. In second section filename will be
+    always printed as segment number will be at-least one more than current. Also if any other parameter
+    is given using appropriate switch, then those new values will be also printed.
    </para>
  
    <para>
*** a/src/bin/pg_resetxlog/pg_resetxlog.c
--- b/src/bin/pg_resetxlog/pg_resetxlog.c
***************
*** 65,73 **** static XLogSegNo newXlogSegNo;	/* new XLOG segment # */
--- 65,83 ----
  static bool guessed = false;	/* T if we had to guess at any values */
  static const char *progname;
  
+ static uint32		set_xid_epoch = (uint32) -1;
+ static TransactionId set_xid = 0;
+ static Oid			set_oid = 0;
+ static MultiXactId set_mxid = 0;
+ static MultiXactOffset set_mxoff = (MultiXactOffset) -1;
+ static uint32		minXlogTli = 0;
+ static XLogSegNo	minXlogSegNo = 0;
+ static XLogSegNo currentXlogSegNo = 0;	/* current segment # from checkpoint */
+ 
  static bool ReadControlFile(void);
  static void GuessControlValues(void);
  static void PrintControlValues(bool guessed);
+ static void PrintNewControlValues(void);
  static void RewriteControlFile(void);
  static void FindEndOfXLOG(void);
  static void KillExistingXLOG(void);
***************
*** 82,95 **** main(int argc, char *argv[])
  	int			c;
  	bool		force = false;
  	bool		noupdate = false;
- 	uint32		set_xid_epoch = (uint32) -1;
- 	TransactionId set_xid = 0;
- 	Oid			set_oid = 0;
- 	MultiXactId set_mxid = 0;
  	MultiXactId set_oldestmxid = 0;
- 	MultiXactOffset set_mxoff = (MultiXactOffset) -1;
- 	uint32		minXlogTli = 0;
- 	XLogSegNo	minXlogSegNo = 0;
  	char	   *endptr;
  	char	   *endptr2;
  	char	   *DataDir;
--- 92,98 ----
***************
*** 302,307 **** main(int argc, char *argv[])
--- 305,317 ----
  	FindEndOfXLOG();
  
  	/*
+ 	 * Print current control file parameters, if had to guess anything and -f
+ 	 * was not given or -n is given.
+ 	 */
+ 	if ((guessed && !force) || noupdate)
+ 		PrintControlValues(guessed);
+ 
+ 	/*
  	 * Adjust fields if required by switches.  (Do this now so that printout,
  	 * if any, includes these values.)
  	 */
***************
*** 352,362 **** main(int argc, char *argv[])
  
  	/*
  	 * If we had to guess anything, and -f was not given, just print the
! 	 * guessed values and exit.  Also print if -n is given.
  	 */
  	if ((guessed && !force) || noupdate)
  	{
! 		PrintControlValues(guessed);
  		if (!noupdate)
  		{
  			printf(_("\nIf these values seem acceptable, use -f to force reset.\n"));
--- 362,372 ----
  
  	/*
  	 * If we had to guess anything, and -f was not given, just print the
! 	 * values to be reset and exit.  Also print value to be reset if -n is given.
  	 */
  	if ((guessed && !force) || noupdate)
  	{
! 		PrintNewControlValues();
  		if (!noupdate)
  		{
  			printf(_("\nIf these values seem acceptable, use -f to force reset.\n"));
***************
*** 561,567 **** PrintControlValues(bool guessed)
  	if (guessed)
  		printf(_("Guessed pg_control values:\n\n"));
  	else
! 		printf(_("pg_control values:\n\n"));
  
  	/*
  	 * Format system_identifier separately to keep platform-dependent format
--- 571,577 ----
  	if (guessed)
  		printf(_("Guessed pg_control values:\n\n"));
  	else
! 		printf(_("Current pg_control values:\n\n"));
  
  	/*
  	 * Format system_identifier separately to keep platform-dependent format
***************
*** 570,576 **** PrintControlValues(bool guessed)
  	snprintf(sysident_str, sizeof(sysident_str), UINT64_FORMAT,
  			 ControlFile.system_identifier);
  
! 	XLogFileName(fname, ControlFile.checkPointCopy.ThisTimeLineID, newXlogSegNo);
  
  	printf(_("First log segment after reset:        %s\n"),
  		   fname);
--- 580,586 ----
  	snprintf(sysident_str, sizeof(sysident_str), UINT64_FORMAT,
  			 ControlFile.system_identifier);
  
! 	XLogFileName(fname, ControlFile.checkPointCopy.ThisTimeLineID, currentXlogSegNo);
  
  	printf(_("First log segment after reset:        %s\n"),
  		   fname);
***************
*** 632,637 **** PrintControlValues(bool guessed)
--- 642,704 ----
  
  
  /*
+  * Print the values to be changed after pg_resetxlog.
+  *
+  * NB: this display should be just for those fields that are
+  * going to change after reset.
+  */
+ static void
+ PrintNewControlValues()
+ {
+ 	char		fname[MAXFNAMELEN];
+ 
+ 	/* This will be always printed in order to keep format same. */
+ 	printf(_("\n\nValues to be used after reset:\n\n"));
+ 
+ 	XLogFileName(fname, ControlFile.checkPointCopy.ThisTimeLineID, newXlogSegNo);
+ 	printf(_("First log segment after reset:        %s\n"), fname);
+ 
+ 	if (set_mxid != 0)
+ 	{
+ 		printf(_("NextMultiXactId:                      %u\n"),
+ 						ControlFile.checkPointCopy.nextMulti);
+ 		printf(_("OldestMultiXid:                       %u\n"),
+ 						ControlFile.checkPointCopy.oldestMulti);
+ 		printf(_("OldestMulti's DB: %u\n"),
+ 						ControlFile.checkPointCopy.oldestMultiDB);
+ 	}
+ 
+ 	if (set_mxoff != -1)
+ 	{
+ 		printf(_("NextMultiOffset:                      %u\n"),
+ 						ControlFile.checkPointCopy.nextMultiOffset);
+ 	}
+ 
+ 	if (set_oid != 0)
+ 	{
+ 		printf(_("NextOID:                              %u\n"),
+ 						ControlFile.checkPointCopy.nextOid);
+ 	}
+ 
+ 	if (set_xid != 0)
+ 	{
+ 		printf(_("NextXID:                              %u\n"),
+ 						ControlFile.checkPointCopy.nextXid);
+ 		printf(_("OldestXID:                            %u\n"),
+ 						ControlFile.checkPointCopy.oldestXid);
+ 		printf(_("OldestXID's DB:   %u\n"),
+ 						ControlFile.checkPointCopy.oldestXidDB);
+ 	}
+ 
+ 	if (set_xid_epoch != -1)
+ 	{
+ 		printf(_("NextXID Epoch:                        %u\n"),
+ 						ControlFile.checkPointCopy.nextXidEpoch);
+ 	}
+ }
+ 
+ 
+ /*
   * Write out the new pg_control file.
   */
  static void
***************
*** 753,758 **** FindEndOfXLOG(void)
--- 820,826 ----
  	 */
  	segs_per_xlogid = (UINT64CONST(0x0000000100000000) / ControlFile.xlog_seg_size);
  	newXlogSegNo = ControlFile.checkPointCopy.redo / ControlFile.xlog_seg_size;
+ 	currentXlogSegNo = newXlogSegNo;
  
  	/*
  	 * Scan the pg_xlog directory to find existing WAL segment files. We
***************
*** 1039,1045 **** usage(void)
  	printf(_("  -f               force update to be done\n"));
  	printf(_("  -l XLOGFILE      force minimum WAL starting location for new transaction log\n"));
  	printf(_("  -m MXID,MXID     set next and oldest multitransaction ID\n"));
! 	printf(_("  -n               no update, just show extracted control values (for testing)\n"));
  	printf(_("  -o OID           set next OID\n"));
  	printf(_("  -O OFFSET        set next multitransaction offset\n"));
  	printf(_("  -V, --version    output version information, then exit\n"));
--- 1107,1113 ----
  	printf(_("  -f               force update to be done\n"));
  	printf(_("  -l XLOGFILE      force minimum WAL starting location for new transaction log\n"));
  	printf(_("  -m MXID,MXID     set next and oldest multitransaction ID\n"));
! 	printf(_("  -n               no update, just show extracted control values (for testing) and to be reset values of parameters(if given)\n"));
  	printf(_("  -o OID           set next OID\n"));
  	printf(_("  -O OFFSET        set next multitransaction offset\n"));
  	printf(_("  -V, --version    output version information, then exit\n"));

*** a/doc/src/sgml/ref/pg_resetxlog.sgml
--- b/doc/src/sgml/ref/pg_resetxlog.sgml
***************
*** 180,185 **** PostgreSQL documentation
--- 180,188 ----
     <filename>pg_control</> and then exit without modifying anything.
     This is mainly a debugging tool, but can be useful as a sanity check
     before allowing <command>pg_resetxlog</command> to proceed for real.
+    It will print values in two sections. In first section it will print
+    all original/guessed values and in second section all values to be
+    used after reset.
    </para>
  
    <para>
*** a/src/bin/pg_resetxlog/pg_resetxlog.c
--- b/src/bin/pg_resetxlog/pg_resetxlog.c
***************
*** 65,73 **** static XLogSegNo newXlogSegNo;	/* new XLOG segment # */
--- 65,82 ----
  static bool guessed = false;	/* T if we had to guess at any values */
  static const char *progname;
  
+ static uint32 set_xid_epoch = (uint32) -1;
+ static TransactionId set_xid = 0;
+ static Oid	set_oid = 0;
+ static MultiXactId set_mxid = 0;
+ static MultiXactOffset set_mxoff = (MultiXactOffset) -1;
+ static uint32 minXlogTli = 0;
+ static XLogSegNo minXlogSegNo = 0;
+ 
  static bool ReadControlFile(void);
  static void GuessControlValues(void);
  static void PrintControlValues(bool guessed);
+ static void PrintNewControlValues(void);
  static void RewriteControlFile(void);
  static void FindEndOfXLOG(void);
  static void KillExistingXLOG(void);
***************
*** 82,95 **** main(int argc, char *argv[])
  	int			c;
  	bool		force = false;
  	bool		noupdate = false;
- 	uint32		set_xid_epoch = (uint32) -1;
- 	TransactionId set_xid = 0;
- 	Oid			set_oid = 0;
- 	MultiXactId set_mxid = 0;
  	MultiXactId set_oldestmxid = 0;
- 	MultiXactOffset set_mxoff = (MultiXactOffset) -1;
- 	uint32		minXlogTli = 0;
- 	XLogSegNo	minXlogSegNo = 0;
  	char	   *endptr;
  	char	   *endptr2;
  	char	   *DataDir;
--- 91,97 ----
***************
*** 302,307 **** main(int argc, char *argv[])
--- 304,316 ----
  	FindEndOfXLOG();
  
  	/*
+ 	 * Print current control file parameters, if had to guess anything and -f
+ 	 * was not given or -n is given.
+ 	 */
+ 	if ((guessed && !force) || noupdate)
+ 		PrintControlValues(guessed);
+ 
+ 	/*
  	 * Adjust fields if required by switches.  (Do this now so that printout,
  	 * if any, includes these values.)
  	 */
***************
*** 352,362 **** main(int argc, char *argv[])
  
  	/*
  	 * If we had to guess anything, and -f was not given, just print the
! 	 * guessed values and exit.  Also print if -n is given.
  	 */
  	if ((guessed && !force) || noupdate)
  	{
! 		PrintControlValues(guessed);
  		if (!noupdate)
  		{
  			printf(_("\nIf these values seem acceptable, use -f to force reset.\n"));
--- 361,372 ----
  
  	/*
  	 * If we had to guess anything, and -f was not given, just print the
! 	 * values to be reset and exit.  Also print value to be reset if -n is
! 	 * given.
  	 */
  	if ((guessed && !force) || noupdate)
  	{
! 		PrintNewControlValues();
  		if (!noupdate)
  		{
  			printf(_("\nIf these values seem acceptable, use -f to force reset.\n"));
***************
*** 556,567 **** static void
  PrintControlValues(bool guessed)
  {
  	char		sysident_str[32];
- 	char		fname[MAXFNAMELEN];
  
  	if (guessed)
  		printf(_("Guessed pg_control values:\n\n"));
  	else
! 		printf(_("pg_control values:\n\n"));
  
  	/*
  	 * Format system_identifier separately to keep platform-dependent format
--- 566,576 ----
  PrintControlValues(bool guessed)
  {
  	char		sysident_str[32];
  
  	if (guessed)
  		printf(_("Guessed pg_control values:\n\n"));
  	else
! 		printf(_("Current pg_control values:\n\n"));
  
  	/*
  	 * Format system_identifier separately to keep platform-dependent format
***************
*** 570,579 **** PrintControlValues(bool guessed)
  	snprintf(sysident_str, sizeof(sysident_str), UINT64_FORMAT,
  			 ControlFile.system_identifier);
  
- 	XLogFileName(fname, ControlFile.checkPointCopy.ThisTimeLineID, newXlogSegNo);
- 
- 	printf(_("First log segment after reset:        %s\n"),
- 		   fname);
  	printf(_("pg_control version number:            %u\n"),
  		   ControlFile.pg_control_version);
  	printf(_("Catalog version number:               %u\n"),
--- 579,584 ----
***************
*** 632,637 **** PrintControlValues(bool guessed)
--- 637,699 ----
  
  
  /*
+  * Print the values to be changed after pg_resetxlog.
+  *
+  * NB: this display should be just for those fields that are
+  * going to change after reset.
+  */
+ static void
+ PrintNewControlValues()
+ {
+ 	char		fname[MAXFNAMELEN];
+ 
+ 	/* This will be always printed in order to keep format same. */
+ 	printf(_("\n\nValues to be used after reset:\n\n"));
+ 
+ 	XLogFileName(fname, ControlFile.checkPointCopy.ThisTimeLineID, newXlogSegNo);
+ 	printf(_("First log segment after reset:        %s\n"), fname);
+ 
+ 	if (set_mxid != 0)
+ 	{
+ 		printf(_("NextMultiXactId:                      %u\n"),
+ 			   ControlFile.checkPointCopy.nextMulti);
+ 		printf(_("OldestMultiXid:                       %u\n"),
+ 			   ControlFile.checkPointCopy.oldestMulti);
+ 		printf(_("OldestMulti's DB:                     %u\n"),
+ 			   ControlFile.checkPointCopy.oldestMultiDB);
+ 	}
+ 
+ 	if (set_mxoff != -1)
+ 	{
+ 		printf(_("NextMultiOffset:                      %u\n"),
+ 			   ControlFile.checkPointCopy.nextMultiOffset);
+ 	}
+ 
+ 	if (set_oid != 0)
+ 	{
+ 		printf(_("NextOID:                              %u\n"),
+ 			   ControlFile.checkPointCopy.nextOid);
+ 	}
+ 
+ 	if (set_xid != 0)
+ 	{
+ 		printf(_("NextXID:                              %u\n"),
+ 			   ControlFile.checkPointCopy.nextXid);
+ 		printf(_("OldestXID:                            %u\n"),
+ 			   ControlFile.checkPointCopy.oldestXid);
+ 		printf(_("OldestXID's DB:                       %u\n"),
+ 			   ControlFile.checkPointCopy.oldestXidDB);
+ 	}
+ 
+ 	if (set_xid_epoch != -1)
+ 	{
+ 		printf(_("NextXID Epoch:                        %u\n"),
+ 			   ControlFile.checkPointCopy.nextXidEpoch);
+ 	}
+ }
+ 
+ 
+ /*
   * Write out the new pg_control file.
   */
  static void
***************
*** 1039,1045 **** usage(void)
  	printf(_("  -f               force update to be done\n"));
  	printf(_("  -l XLOGFILE      force minimum WAL starting location for new transaction log\n"));
  	printf(_("  -m MXID,MXID     set next and oldest multitransaction ID\n"));
! 	printf(_("  -n               no update, just show extracted control values (for testing)\n"));
  	printf(_("  -o OID           set next OID\n"));
  	printf(_("  -O OFFSET        set next multitransaction offset\n"));
  	printf(_("  -V, --version    output version information, then exit\n"));
--- 1101,1107 ----
  	printf(_("  -f               force update to be done\n"));
  	printf(_("  -l XLOGFILE      force minimum WAL starting location for new transaction log\n"));
  	printf(_("  -m MXID,MXID     set next and oldest multitransaction ID\n"));
! 	printf(_("  -n               no update, just show extracted and to be reset control values.\n"));
  	printf(_("  -o OID           set next OID\n"));
  	printf(_("  -O OFFSET        set next multitransaction offset\n"));
  	printf(_("  -V, --version    output version information, then exit\n"));

diff --git a/doc/src/sgml/ref/pg_resetxlog.sgml b/doc/src/sgml/ref/pg_resetxlog.sgml
index c680680..f7876d0 100644
--- a/doc/src/sgml/ref/pg_resetxlog.sgml
+++ b/doc/src/sgml/ref/pg_resetxlog.sgml
@@ -177,9 +177,10 @@ PostgreSQL documentation
   <para>
    The <option>-n</> (no operation) option instructs
    <command>pg_resetxlog</command> to print the values reconstructed from
-   <filename>pg_control</> and then exit without modifying anything.
-   This is mainly a debugging tool, but can be useful as a sanity check
-   before allowing <command>pg_resetxlog</command> to proceed for real.
+   <filename>pg_control</> and values to be used after reset and then exit
+   without modifying anything. This is mainly a debugging tool, but can be
+   useful as a sanity check before allowing <command>pg_resetxlog</command>
+   to proceed for real.
   </para>
 
   <para>
diff --git a/src/bin/pg_resetxlog/pg_resetxlog.c b/src/bin/pg_resetxlog/pg_resetxlog.c
index f1b5d6d..73faceb 100644
--- a/src/bin/pg_resetxlog/pg_resetxlog.c
+++ b/src/bin/pg_resetxlog/pg_resetxlog.c
@@ -64,10 +64,18 @@ static ControlFileData ControlFile;		/* pg_control values */
 static XLogSegNo newXlogSegNo;	/* new XLOG segment # */
 static bool guessed = false;	/* T if we had to guess at any values */
 static const char *progname;
+static uint32 set_xid_epoch = (uint32) -1;
+static TransactionId set_xid = 0;
+static Oid	set_oid = 0;
+static MultiXactId set_mxid = 0;
+static MultiXactOffset set_mxoff = (MultiXactOffset) -1;
+static uint32 minXlogTli = 0;
+static XLogSegNo minXlogSegNo = 0;
 
 static bool ReadControlFile(void);
 static void GuessControlValues(void);
 static void PrintControlValues(bool guessed);
+static void PrintNewControlValues(void);
 static void RewriteControlFile(void);
 static void FindEndOfXLOG(void);
 static void KillExistingXLOG(void);
@@ -82,14 +90,7 @@ main(int argc, char *argv[])
 	int			c;
 	bool		force = false;
 	bool		noupdate = false;
-	uint32		set_xid_epoch = (uint32) -1;
-	TransactionId set_xid = 0;
-	Oid			set_oid = 0;
-	MultiXactId set_mxid = 0;
 	MultiXactId set_oldestmxid = 0;
-	MultiXactOffset set_mxoff = (MultiXactOffset) -1;
-	uint32		minXlogTli = 0;
-	XLogSegNo	minXlogSegNo = 0;
 	char	   *endptr;
 	char	   *endptr2;
 	char	   *DataDir;
@@ -302,6 +303,13 @@ main(int argc, char *argv[])
 	FindEndOfXLOG();
 
 	/*
+	 * Print current control file parameters, if we had to guess anything and
+	 * -f was not given or -n is given.
+	 */
+	if ((guessed && !force) || noupdate)
+		PrintControlValues(guessed);
+
+	/*
 	 * Adjust fields if required by switches.  (Do this now so that printout,
 	 * if any, includes these values.)
 	 */
@@ -352,11 +360,12 @@ main(int argc, char *argv[])
 
 	/*
 	 * If we had to guess anything, and -f was not given, just print the
-	 * guessed values and exit.  Also print if -n is given.
+	 * values to be reset and exit.  Also print value to be reset if -n is
+	 * given.
 	 */
 	if ((guessed && !force) || noupdate)
 	{
-		PrintControlValues(guessed);
+		PrintNewControlValues();
 		if (!noupdate)
 		{
 			printf(_("\nIf these values seem acceptable, use -f to force reset.\n"));
@@ -556,12 +565,11 @@ static void
 PrintControlValues(bool guessed)
 {
 	char		sysident_str[32];
-	char		fname[MAXFNAMELEN];
 
 	if (guessed)
 		printf(_("Guessed pg_control values:\n\n"));
 	else
-		printf(_("pg_control values:\n\n"));
+		printf(_("Current pg_control values:\n\n"));
 
 	/*
 	 * Format system_identifier separately to keep platform-dependent format
@@ -570,10 +578,6 @@ PrintControlValues(bool guessed)
 	snprintf(sysident_str, sizeof(sysident_str), UINT64_FORMAT,
 			 ControlFile.system_identifier);
 
-	XLogFileName(fname, ControlFile.checkPointCopy.ThisTimeLineID, newXlogSegNo);
-
-	printf(_("First log segment after reset:        %s\n"),
-		   fname);
 	printf(_("pg_control version number:            %u\n"),
 		   ControlFile.pg_control_version);
 	printf(_("Catalog version number:               %u\n"),
@@ -632,6 +636,63 @@ PrintControlValues(bool guessed)
 
 
 /*
+ * Print the values to be changed after pg_resetxlog.
+ *
+ * NB: this display should be just for those fields that are
+ * going to change after reset.
+ */
+static void
+PrintNewControlValues()
+{
+	char		fname[MAXFNAMELEN];
+
+	/* This will be always printed in order to keep format same. */
+	printf(_("\n\nValues to be used after reset:\n\n"));
+
+	XLogFileName(fname, ControlFile.checkPointCopy.ThisTimeLineID, newXlogSegNo);
+	printf(_("First log segment after reset:        %s\n"), fname);
+
+	if (set_mxid != 0)
+	{
+		printf(_("NextMultiXactId:                      %u\n"),
+			   ControlFile.checkPointCopy.nextMulti);
+		printf(_("OldestMultiXid:                       %u\n"),
+			   ControlFile.checkPointCopy.oldestMulti);
+		printf(_("OldestMulti's DB:                     %u\n"),
+			   ControlFile.checkPointCopy.oldestMultiDB);
+	}
+
+	if (set_mxoff != -1)
+	{
+		printf(_("NextMultiOffset:                      %u\n"),
+			   ControlFile.checkPointCopy.nextMultiOffset);
+	}
+
+	if (set_oid != 0)
+	{
+		printf(_("NextOID:                              %u\n"),
+			   ControlFile.checkPointCopy.nextOid);
+	}
+
+	if (set_xid != 0)
+	{
+		printf(_("NextXID:                              %u\n"),
+			   ControlFile.checkPointCopy.nextXid);
+		printf(_("OldestXID:                            %u\n"),
+			   ControlFile.checkPointCopy.oldestXid);
+		printf(_("OldestXID's DB:                       %u\n"),
+			   ControlFile.checkPointCopy.oldestXidDB);
+	}
+
+	if (set_xid_epoch != -1)
+	{
+		printf(_("NextXID Epoch:                        %u\n"),
+			   ControlFile.checkPointCopy.nextXidEpoch);
+	}
+}
+
+
+/*
  * Write out the new pg_control file.
  */
 static void
@@ -1039,7 +1100,7 @@ usage(void)
 	printf(_("  -f               force update to be done\n"));
 	printf(_("  -l XLOGFILE      force minimum WAL starting location for new transaction log\n"));
 	printf(_("  -m MXID,MXID     set next and oldest multitransaction ID\n"));
-	printf(_("  -n               no update, just show extracted control values (for testing)\n"));
+	printf(_("  -n               no update, just show extracted and reset control values (for testing)\n"));
 	printf(_("  -o OID           set next OID\n"));
 	printf(_("  -O OFFSET        set next multitransaction offset\n"));
 	printf(_("  -V, --version    output version information, then exit\n"));