Split out recovery confing-writing code from pg_basebackup

... into a new file, fe_utils/recovery_gen.c.

This can later be used by pg_rewind.

Authors: Paul Guo, Jimmy Yih, Ashwin Agrawal.  A few tweaks by Álvaro Herrera
Reviewed-by: Michaël Paquier
Discussion: https://postgr.es/m/CAEET0ZEffUkXc48pg2iqARQgGRYDiiVxDu+yYek_bTwJF+q=Uw@mail.gmail.com

1 files changed, 3 insertions, 159 deletions

diff --git a/src/bin/pg_basebackup/pg_basebackup.c b/src/bin/pg_basebackup/pg_basebackup.c
index 7986872f106..55ef13926da 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"
@@ -68,11 +69,6 @@ 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
  */
 typedef enum
@@ -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