v6-0001-Extact-common-functions-from-pg_basebackup-into-s.patch

From 9f8883341075d44ab699b468e3cc8bf200deb72d Mon Sep 17 00:00:00 2001
From: Paul Guo <paulguo@gmail.com>
Date: Thu, 18 Apr 2019 18:55:09 +0800
Subject: [PATCH v6 1/3] Extact common functions from pg_basebackup into
 separate files for pg_rewind use.

---
 src/bin/pg_basebackup/pg_basebackup.c | 162 +------------------------
 src/bin/pg_rewind/libpq_fetch.c       |   3 +-
 src/bin/pg_rewind/pg_rewind.c         |   9 ++
 src/bin/pg_rewind/pg_rewind.h         |   3 +
 src/fe_utils/Makefile                 |   2 +-
 src/fe_utils/recovery_gen.c           | 165 ++++++++++++++++++++++++++
 src/include/fe_utils/recovery_gen.h   |  25 ++++
 7 files changed, 207 insertions(+), 162 deletions(-)
 create mode 100644 src/fe_utils/recovery_gen.c
 create mode 100644 src/include/fe_utils/recovery_gen.h

diff --git a/src/bin/pg_basebackup/pg_basebackup.c b/src/bin/pg_basebackup/pg_basebackup.c
index 7986872f10..55ef13926d 100644
--- a/src/bin/pg_basebackup/pg_basebackup.c
+++ b/src/bin/pg_basebackup/pg_basebackup.c
@@ -31,6 +31,7 @@
 #include "common/file_utils.h"
 #include "common/logging.h"
 #include "common/string.h"
+#include "fe_utils/recovery_gen.h"
 #include "fe_utils/string_utils.h"
 #include "getopt_long.h"
 #include "libpq-fe.h"
@@ -67,11 +68,6 @@ typedef struct TablespaceList
  */
 #define MINIMUM_VERSION_FOR_TEMP_SLOTS 100000
 
-/*
- * recovery.conf is integrated into postgresql.conf from version 12.
- */
-#define MINIMUM_VERSION_FOR_RECOVERY_GUC 120000
-
 /*
  * Different ways to include WAL
  */
@@ -147,8 +143,6 @@ static void progress_report(int tablespacenum, const char *filename, bool force)
 
 static void ReceiveTarFile(PGconn *conn, PGresult *res, int rownum);
 static void ReceiveAndUnpackTarFile(PGconn *conn, PGresult *res, int rownum);
-static void GenerateRecoveryConf(PGconn *conn);
-static void WriteRecoveryConf(void);
 static void BaseBackup(void);
 
 static bool reached_end_position(XLogRecPtr segendpos, uint32 timeline,
@@ -1629,7 +1623,7 @@ ReceiveAndUnpackTarFile(PGconn *conn, PGresult *res, int rownum)
 		PQfreemem(copybuf);
 
 	if (basetablespace && writerecoveryconf)
-		WriteRecoveryConf();
+		WriteRecoveryConfig(conn, basedir, recoveryconfcontents);
 
 	/*
 	 * No data is synced here, everything is done for all tablespaces at the
@@ -1637,156 +1631,6 @@ ReceiveAndUnpackTarFile(PGconn *conn, PGresult *res, int rownum)
 	 */
 }
 
-/*
- * Escape a string so that it can be used as a value in a key-value pair
- * a configuration file.
- */
-static char *
-escape_quotes(const char *src)
-{
-	char	   *result = escape_single_quotes_ascii(src);
-
-	if (!result)
-	{
-		pg_log_error("out of memory");
-		exit(1);
-	}
-	return result;
-}
-
-/*
- * Create a configuration file in memory using a PQExpBuffer
- */
-static void
-GenerateRecoveryConf(PGconn *conn)
-{
-	PQconninfoOption *connOptions;
-	PQconninfoOption *option;
-	PQExpBufferData conninfo_buf;
-	char	   *escaped;
-
-	recoveryconfcontents = createPQExpBuffer();
-	if (!recoveryconfcontents)
-	{
-		pg_log_error("out of memory");
-		exit(1);
-	}
-
-	/*
-	 * In PostgreSQL 12 and newer versions, standby_mode is gone, replaced by
-	 * standby.signal to trigger a standby state at recovery.
-	 */
-	if (PQserverVersion(conn) < MINIMUM_VERSION_FOR_RECOVERY_GUC)
-		appendPQExpBufferStr(recoveryconfcontents, "standby_mode = 'on'\n");
-
-	connOptions = PQconninfo(conn);
-	if (connOptions == NULL)
-	{
-		pg_log_error("out of memory");
-		exit(1);
-	}
-
-	initPQExpBuffer(&conninfo_buf);
-	for (option = connOptions; option && option->keyword; option++)
-	{
-		/* Omit empty settings and those libpqwalreceiver overrides. */
-		if (strcmp(option->keyword, "replication") == 0 ||
-			strcmp(option->keyword, "dbname") == 0 ||
-			strcmp(option->keyword, "fallback_application_name") == 0 ||
-			(option->val == NULL) ||
-			(option->val != NULL && option->val[0] == '\0'))
-			continue;
-
-		/* Separate key-value pairs with spaces */
-		if (conninfo_buf.len != 0)
-			appendPQExpBufferChar(&conninfo_buf, ' ');
-
-		/*
-		 * Write "keyword=value" pieces, the value string is escaped and/or
-		 * quoted if necessary.
-		 */
-		appendPQExpBuffer(&conninfo_buf, "%s=", option->keyword);
-		appendConnStrVal(&conninfo_buf, option->val);
-	}
-
-	/*
-	 * Escape the connection string, so that it can be put in the config file.
-	 * Note that this is different from the escaping of individual connection
-	 * options above!
-	 */
-	escaped = escape_quotes(conninfo_buf.data);
-	appendPQExpBuffer(recoveryconfcontents, "primary_conninfo = '%s'\n", escaped);
-	free(escaped);
-
-	if (replication_slot)
-	{
-		/* unescaped: ReplicationSlotValidateName allows [a-z0-9_] only */
-		appendPQExpBuffer(recoveryconfcontents, "primary_slot_name = '%s'\n",
-						  replication_slot);
-	}
-
-	if (PQExpBufferBroken(recoveryconfcontents) ||
-		PQExpBufferDataBroken(conninfo_buf))
-	{
-		pg_log_error("out of memory");
-		exit(1);
-	}
-
-	termPQExpBuffer(&conninfo_buf);
-
-	PQconninfoFree(connOptions);
-}
-
-
-/*
- * Write the configuration file into the directory specified in basedir,
- * with the contents already collected in memory appended.  Then write
- * the signal file into the basedir.  If the server does not support
- * recovery parameters as GUCs, the signal file is not necessary, and
- * configuration is written to recovery.conf.
- */
-static void
-WriteRecoveryConf(void)
-{
-	char		filename[MAXPGPATH];
-	FILE	   *cf;
-	bool		is_recovery_guc_supported = true;
-
-	if (PQserverVersion(conn) < MINIMUM_VERSION_FOR_RECOVERY_GUC)
-		is_recovery_guc_supported = false;
-
-	snprintf(filename, MAXPGPATH, "%s/%s", basedir,
-			 is_recovery_guc_supported ? "postgresql.auto.conf" : "recovery.conf");
-
-	cf = fopen(filename, is_recovery_guc_supported ? "a" : "w");
-	if (cf == NULL)
-	{
-		pg_log_error("could not open file \"%s\": %m", filename);
-		exit(1);
-	}
-
-	if (fwrite(recoveryconfcontents->data, recoveryconfcontents->len, 1, cf) != 1)
-	{
-		pg_log_error("could not write to file \"%s\": %m", filename);
-		exit(1);
-	}
-
-	fclose(cf);
-
-	if (is_recovery_guc_supported)
-	{
-		snprintf(filename, MAXPGPATH, "%s/%s", basedir, "standby.signal");
-		cf = fopen(filename, "w");
-		if (cf == NULL)
-		{
-			pg_log_error("could not create file \"%s\": %m", filename);
-			exit(1);
-		}
-
-		fclose(cf);
-	}
-}
-
 
 static void
 BaseBackup(void)
@@ -1843,7 +1687,7 @@ BaseBackup(void)
 	 * Build contents of configuration file if requested
 	 */
 	if (writerecoveryconf)
-		GenerateRecoveryConf(conn);
+		recoveryconfcontents = GenerateRecoveryConfig(conn, replication_slot);
 
 	/*
 	 * Run IDENTIFY_SYSTEM so we can get the timeline
diff --git a/src/bin/pg_rewind/libpq_fetch.c b/src/bin/pg_rewind/libpq_fetch.c
index 002776f696..f4ebf7d842 100644
--- a/src/bin/pg_rewind/libpq_fetch.c
+++ b/src/bin/pg_rewind/libpq_fetch.c
@@ -20,12 +20,11 @@
 #include "file_ops.h"
 #include "filemap.h"
 
-#include "libpq-fe.h"
 #include "catalog/pg_type_d.h"
 #include "fe_utils/connect.h"
 #include "port/pg_bswap.h"
 
-static PGconn *conn = NULL;
+PGconn *conn = NULL;
 
 /*
  * Files are fetched max CHUNKSIZE bytes at a time.
diff --git a/src/bin/pg_rewind/pg_rewind.c b/src/bin/pg_rewind/pg_rewind.c
index 15e3eab550..c3903c5753 100644
--- a/src/bin/pg_rewind/pg_rewind.c
+++ b/src/bin/pg_rewind/pg_rewind.c
@@ -85,6 +85,12 @@ usage(const char *progname)
 	printf(_("\nReport bugs to <pgsql-bugs@lists.postgresql.org>.\n"));
 }
 
+static void
+disconnect_atexit(void)
+{
+	if (conn != NULL)
+		PQfinish(conn);
+}
 
 int
 main(int argc, char **argv)
@@ -231,7 +237,10 @@ main(int argc, char **argv)
 
 	/* Connect to remote server */
 	if (connstr_source)
+	{
 		libpqConnect(connstr_source);
+		atexit(disconnect_atexit);
+	}
 
 	/*
 	 * Ok, we have all the options and we're ready to start. Read in all the
diff --git a/src/bin/pg_rewind/pg_rewind.h b/src/bin/pg_rewind/pg_rewind.h
index 1125c7e60f..d23c855107 100644
--- a/src/bin/pg_rewind/pg_rewind.h
+++ b/src/bin/pg_rewind/pg_rewind.h
@@ -19,6 +19,8 @@
 
 #include "common/logging.h"
 
+#include "libpq-fe.h"
+
 /* Configuration options */
 extern char *datadir_target;
 extern char *datadir_source;
@@ -26,6 +28,7 @@ extern char *connstr_source;
 extern bool showprogress;
 extern bool dry_run;
 extern int	WalSegSz;
+extern PGconn *conn;
 
 /* Target history */
 extern TimeLineHistoryEntry *targetHistory;
diff --git a/src/fe_utils/Makefile b/src/fe_utils/Makefile
index 7d73800323..ae0f6c884b 100644
--- a/src/fe_utils/Makefile
+++ b/src/fe_utils/Makefile
@@ -19,7 +19,7 @@ include $(top_builddir)/src/Makefile.global
 
 override CPPFLAGS := -DFRONTEND -I$(libpq_srcdir) $(CPPFLAGS)
 
-OBJS = mbprint.o print.o psqlscan.o simple_list.o string_utils.o conditional.o
+OBJS = mbprint.o print.o psqlscan.o simple_list.o string_utils.o conditional.o recovery_gen.o
 
 all: libpgfeutils.a
 
diff --git a/src/fe_utils/recovery_gen.c b/src/fe_utils/recovery_gen.c
new file mode 100644
index 0000000000..4e0f6a154a
--- /dev/null
+++ b/src/fe_utils/recovery_gen.c
@@ -0,0 +1,165 @@
+/*-------------------------------------------------------------------------
+ *
+ * recovery_gen.c - general code that is used in both pg_basebackup and pg_rewind.
+ *
+ * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#include "postgres_fe.h"
+#include "common/logging.h"
+#include "fe_utils/string_utils.h"
+#include "fe_utils/recovery_gen.h"
+
+/*
+ * Escape a string so that it can be used as a value in a key-value pair
+ * a configuration file.
+ */
+static char *
+escape_quotes(const char *src)
+{
+	char	   *result = escape_single_quotes_ascii(src);
+
+	if (!result)
+	{
+		pg_log_error("out of memory");
+		exit(1);
+	}
+	return result;
+}
+
+/*
+ * Create recovery configuration contents using a PQExpBuffer
+ */
+PQExpBuffer
+GenerateRecoveryConfig(PGconn *pgconn, char *pg_replication_slot)
+{
+	PQconninfoOption *connOptions;
+	PQconninfoOption *option;
+	PQExpBufferData   conninfo_buf;
+	char			 *escaped;
+	PQExpBuffer		  contents;
+
+	contents = createPQExpBuffer();
+	if (!contents)
+	{
+		pg_log_error("out of memory");
+		exit(1);
+	}
+
+	/*
+	 * In PostgreSQL 12 and newer versions, standby_mode is gone, replaced by
+	 * standby.signal to trigger a standby state at recovery.
+	 */
+	if (pgconn && PQserverVersion(pgconn) < MINIMUM_VERSION_FOR_RECOVERY_GUC)
+		appendPQExpBufferStr(contents, "standby_mode = 'on'\n");
+
+	connOptions = PQconninfo(pgconn);
+	if (connOptions == NULL)
+	{
+		pg_log_error("out of memory");
+		exit(1);
+	}
+
+	initPQExpBuffer(&conninfo_buf);
+	for (option = connOptions; option && option->keyword; option++)
+	{
+		/* Omit empty settings and those libpqwalreceiver overrides. */
+		if (strcmp(option->keyword, "replication") == 0 ||
+			strcmp(option->keyword, "dbname") == 0 ||
+			strcmp(option->keyword, "fallback_application_name") == 0 ||
+			(option->val == NULL) ||
+			(option->val != NULL && option->val[0] == '\0'))
+			continue;
+
+		/* Separate key-value pairs with spaces */
+		if (conninfo_buf.len != 0)
+			appendPQExpBufferChar(&conninfo_buf, ' ');
+
+		/*
+		 * Write "keyword=value" pieces, the value string is escaped and/or
+		 * quoted if necessary.
+		 */
+		appendPQExpBuffer(&conninfo_buf, "%s=", option->keyword);
+		appendConnStrVal(&conninfo_buf, option->val);
+	}
+
+	/*
+	 * Escape the connection string, so that it can be put in the config file.
+	 * Note that this is different from the escaping of individual connection
+	 * options above!
+	 */
+	escaped = escape_quotes(conninfo_buf.data);
+	appendPQExpBuffer(contents, "primary_conninfo = '%s'\n", escaped);
+	free(escaped);
+
+	if (pg_replication_slot)
+	{
+		/* unescaped: ReplicationSlotValidateName allows [a-z0-9_] only */
+		appendPQExpBuffer(contents, "primary_slot_name = '%s'\n",
+						  pg_replication_slot);
+	}
+
+	if (PQExpBufferBroken(contents) ||
+		PQExpBufferDataBroken(conninfo_buf))
+	{
+		pg_log_error("out of memory");
+		exit(1);
+	}
+
+	termPQExpBuffer(&conninfo_buf);
+
+	PQconninfoFree(connOptions);
+
+	return contents;
+}
+
+/*
+ * Write the configuration file in the directory specified in target_dir,
+ * with the contents already collected in memory appended.  Then write
+ * the signal file into the target_dir.  If the server does not support
+ * recovery parameters as GUCs, the signal file is not necessary, and
+ * configuration is written to recovery.conf.
+ */
+void
+WriteRecoveryConfig(PGconn *pgconn, char *target_dir, PQExpBuffer contents)
+{
+	char		filename[MAXPGPATH];
+	FILE	   *cf;
+	bool		is_recovery_guc_supported = true;
+
+	if (pgconn && PQserverVersion(pgconn) < MINIMUM_VERSION_FOR_RECOVERY_GUC)
+		is_recovery_guc_supported = false;
+
+	snprintf(filename, MAXPGPATH, "%s/%s", target_dir,
+			 is_recovery_guc_supported ? "postgresql.auto.conf" : "recovery.conf");
+
+	cf = fopen(filename, is_recovery_guc_supported ? "a" : "w");
+	if (cf == NULL)
+	{
+		pg_log_error("could not open file \"%s\": %m", filename);
+		exit(1);
+	}
+
+	if (fwrite(contents->data, contents->len, 1, cf) != 1)
+	{
+		pg_log_error("could not write to file \"%s\": %m", filename);
+		exit(1);
+	}
+
+	fclose(cf);
+
+	if (is_recovery_guc_supported)
+	{
+		snprintf(filename, MAXPGPATH, "%s/%s", target_dir, "standby.signal");
+		cf = fopen(filename, "w");
+		if (cf == NULL)
+		{
+			pg_log_error("could not create file \"%s\": %m", filename);
+			exit(1);
+		}
+
+		fclose(cf);
+	}
+}
diff --git a/src/include/fe_utils/recovery_gen.h b/src/include/fe_utils/recovery_gen.h
new file mode 100644
index 0000000000..7a79bf110b
--- /dev/null
+++ b/src/include/fe_utils/recovery_gen.h
@@ -0,0 +1,25 @@
+/*-------------------------------------------------------------------------
+ *
+ * recovery_gen.h - general code that is used in both pg_basebackup and pg_rewind.
+ *
+ * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
+ *
+ *-------------------------------------------------------------------------
+ */
+
+#ifndef RECOVERY_GEN_H
+#define RECOVERY_GEN_H
+
+#include "libpq-fe.h"
+#include "pqexpbuffer.h"
+
+extern PQExpBuffer GenerateRecoveryConfig(PGconn *pgconn, char *pg_replication_slot);
+extern void WriteRecoveryConfig(PGconn *pgconn, char *target_dir, PQExpBuffer contents);
+
+/*
+ * recovery.conf is integrated into postgresql.conf from version 12.
+ */
+#define MINIMUM_VERSION_FOR_RECOVERY_GUC 120000
+
+
+#endif							/* RECOVERY_GEN_H */
-- 
2.17.2