Add pg_upgrade to /contrib; will be in 9.0 beta2.

Add documentation.

Supports migration from PG 8.3 and 8.4.

contrib/pg_upgrade/server.c

@@ -0,0 +1,316 @@
+/*
+ *	server.c
+ *
+ *	database server functions
+ */
+
+#include "pg_upgrade.h"
+
+#define POSTMASTER_UPTIME 20
+
+#define STARTUP_WARNING_TRIES 2
+
+
+static pgpid_t get_postmaster_pid(migratorContext *ctx, const char *datadir);
+static bool test_server_conn(migratorContext *ctx, int timeout,
+				 Cluster whichCluster);
+
+
+/*
+ * connectToServer()
+ *
+ *	Connects to the desired database on the designated server.
+ *	If the connection attempt fails, this function logs an error
+ *	message and calls exit_nicely() to kill the program.
+ */
+PGconn *
+connectToServer(migratorContext *ctx, const char *db_name,
+				Cluster whichCluster)
+{
+	char		connectString[MAXPGPATH];
+	unsigned short port = (whichCluster == CLUSTER_OLD) ?
+	ctx->old.port : ctx->new.port;
+	PGconn	   *conn;
+
+	snprintf(connectString, sizeof(connectString),
+			 "dbname = '%s' user = '%s' port = %d", db_name, ctx->user, port);
+
+	conn = PQconnectdb(connectString);
+
+	if (conn == NULL || PQstatus(conn) != CONNECTION_OK)
+	{
+		pg_log(ctx, PG_REPORT, "Connection to database failed: %s\n",
+			   PQerrorMessage(conn));
+
+		if (conn)
+			PQfinish(conn);
+
+		exit_nicely(ctx, true);
+	}
+
+	return conn;
+}
+
+
+/*
+ * executeQueryOrDie()
+ *
+ *	Formats a query string from the given arguments and executes the
+ *	resulting query.  If the query fails, this function logs an error
+ *	message and calls exit_nicely() to kill the program.
+ */
+PGresult *
+executeQueryOrDie(migratorContext *ctx, PGconn *conn, const char *fmt,...)
+{
+	static char command[8192];
+	va_list		args;
+	PGresult   *result;
+	ExecStatusType status;
+
+	va_start(args, fmt);
+	vsnprintf(command, sizeof(command), fmt, args);
+	va_end(args);
+
+	pg_log(ctx, PG_DEBUG, "executing: %s\n", command);
+	result = PQexec(conn, command);
+	status = PQresultStatus(result);
+
+	if ((status != PGRES_TUPLES_OK) && (status != PGRES_COMMAND_OK))
+	{
+		pg_log(ctx, PG_REPORT, "DB command failed\n%s\n%s\n", command,
+			   PQerrorMessage(conn));
+		PQclear(result);
+		PQfinish(conn);
+		exit_nicely(ctx, true);
+		return NULL;			/* Never get here, but keeps compiler happy */
+	}
+	else
+		return result;
+}
+
+
+/*
+ * get_postmaster_pid()
+ *
+ * Returns the pid of the postmaster running on datadir. pid is retrieved
+ * from the postmaster.pid file
+ */
+static pgpid_t
+get_postmaster_pid(migratorContext *ctx, const char *datadir)
+{
+	FILE	   *pidf;
+	long		pid;
+	char		pid_file[MAXPGPATH];
+
+	snprintf(pid_file, sizeof(pid_file), "%s/postmaster.pid", datadir);
+	pidf = fopen(pid_file, "r");
+
+	if (pidf == NULL)
+		return (pgpid_t) 0;
+
+	if (fscanf(pidf, "%ld", &pid) != 1)
+	{
+		fclose(pidf);
+		pg_log(ctx, PG_FATAL, "%s: invalid data in PID file \"%s\"\n",
+			   ctx->progname, pid_file);
+	}
+
+	fclose(pidf);
+
+	return (pgpid_t) pid;
+}
+
+
+/*
+ * get_major_server_version()
+ *
+ * gets the version (in unsigned int form) for the given "datadir". Assumes
+ * that datadir is an absolute path to a valid pgdata directory. The version
+ * is retrieved by reading the PG_VERSION file.
+ */
+uint32
+get_major_server_version(migratorContext *ctx, char **verstr, Cluster whichCluster)
+{
+	const char *datadir = whichCluster == CLUSTER_OLD ?
+	ctx->old.pgdata : ctx->new.pgdata;
+	FILE	   *version_fd;
+	char		ver_file[MAXPGPATH];
+	int			integer_version = 0;
+	int			fractional_version = 0;
+
+	*verstr = pg_malloc(ctx, 64);
+
+	snprintf(ver_file, sizeof(ver_file), "%s/PG_VERSION", datadir);
+	if ((version_fd = fopen(ver_file, "r")) == NULL)
+		return 0;
+
+	if (fscanf(version_fd, "%63s", *verstr) == 0 ||
+		sscanf(*verstr, "%d.%d", &integer_version, &fractional_version) != 2)
+	{
+		pg_log(ctx, PG_FATAL, "could not get version from %s\n", datadir);
+		fclose(version_fd);
+		return 0;
+	}
+
+	return (100 * integer_version + fractional_version) * 100;
+}
+
+
+void
+start_postmaster(migratorContext *ctx, Cluster whichCluster, bool quiet)
+{
+	char		cmd[MAXPGPATH];
+	const char *bindir;
+	const char *datadir;
+	unsigned short port;
+
+	if (whichCluster == CLUSTER_OLD)
+	{
+		bindir = ctx->old.bindir;
+		datadir = ctx->old.pgdata;
+		port = ctx->old.port;
+	}
+	else
+	{
+		bindir = ctx->new.bindir;
+		datadir = ctx->new.pgdata;
+		port = ctx->new.port;
+	}
+
+	/* use -l for Win32 */
+	sprintf(cmd, SYSTEMQUOTE "\"%s/pg_ctl\" -l \"%s\" -D \"%s\" "
+	"-o \"-p %d -c autovacuum=off -c autovacuum_freeze_max_age=2000000000\" "
+			"start >> \"%s\" 2>&1" SYSTEMQUOTE,
+			bindir, ctx->logfile, datadir, port, ctx->logfile);
+	exec_prog(ctx, true, "%s", cmd);
+
+	/* wait for the server to start properly */
+
+	if (test_server_conn(ctx, POSTMASTER_UPTIME, whichCluster) == false)
+		pg_log(ctx, PG_FATAL, " Unable to start %s postmaster with the command: %s\nPerhaps pg_hba.conf was not set to \"trust\".",
+			   CLUSTERNAME(whichCluster), cmd);
+
+	if ((ctx->postmasterPID = get_postmaster_pid(ctx, datadir)) == 0)
+		pg_log(ctx, PG_FATAL, " Unable to get postmaster pid\n");
+	ctx->running_cluster = whichCluster;
+}
+
+
+void
+stop_postmaster(migratorContext *ctx, bool fast, bool quiet)
+{
+	const char *bindir;
+	const char *datadir;
+
+	if (ctx->running_cluster == CLUSTER_OLD)
+	{
+		bindir = ctx->old.bindir;
+		datadir = ctx->old.pgdata;
+	}
+	else if (ctx->running_cluster == CLUSTER_NEW)
+	{
+		bindir = ctx->new.bindir;
+		datadir = ctx->new.pgdata;
+	}
+	else
+		return;					/* no cluster running */
+
+	/* use -l for Win32 */
+	exec_prog(ctx, fast ? false : true,
+			  SYSTEMQUOTE "\"%s/pg_ctl\" -l \"%s\" -D \"%s\" %s stop >> \"%s\" 2>&1" SYSTEMQUOTE,
+		 bindir, ctx->logfile, datadir, fast ? "-m fast" : "", ctx->logfile);
+
+	ctx->postmasterPID = 0;
+	ctx->running_cluster = NONE;
+}
+
+
+/*
+ * test_server_conn()
+ *
+ * tests whether postmaster is running or not by trying to connect
+ * to it. If connection is unsuccessfull we do a sleep of 1 sec and then
+ * try the connection again. This process continues "timeout" times.
+ *
+ * Returns true if the connection attempt was successfull, false otherwise.
+ */
+static bool
+test_server_conn(migratorContext *ctx, int timeout, Cluster whichCluster)
+{
+	PGconn	   *conn = NULL;
+	char		con_opts[MAX_STRING];
+	int			tries;
+	unsigned short port = (whichCluster == CLUSTER_OLD) ?
+	ctx->old.port : ctx->new.port;
+	bool		ret = false;
+
+	snprintf(con_opts, sizeof(con_opts),
+			 "dbname = 'template1' user = '%s' port = %d ", ctx->user, port);
+
+	for (tries = 0; tries < timeout; tries++)
+	{
+		sleep(1);
+		if ((conn = PQconnectdb(con_opts)) != NULL &&
+			PQstatus(conn) == CONNECTION_OK)
+		{
+			PQfinish(conn);
+			ret = true;
+			break;
+		}
+
+		if (tries == STARTUP_WARNING_TRIES)
+			prep_status(ctx, "Trying to start %s server ",
+						CLUSTERNAME(whichCluster));
+		else if (tries > STARTUP_WARNING_TRIES)
+			pg_log(ctx, PG_REPORT, ".");
+	}
+
+	if (tries > STARTUP_WARNING_TRIES)
+		check_ok(ctx);
+
+	return ret;
+}
+
+
+/*
+ * check_for_libpq_envvars()
+ *
+ * tests whether any libpq environment variables are set.
+ * Since pg_upgrade connects to both the old and the new server,
+ * it is potentially dangerous to have any of these set.
+ *
+ * If any are found, will log them and cancel.
+ */
+void
+check_for_libpq_envvars(migratorContext *ctx)
+{
+	PQconninfoOption *option;
+	PQconninfoOption *start;
+	bool		found = false;
+
+	/* Get valid libpq env vars from the PQconndefaults function */
+
+	start = option = PQconndefaults();
+
+	while (option->keyword != NULL)
+	{
+		const char *value;
+
+		if (option->envvar && (value = getenv(option->envvar)) && strlen(value) > 0)
+		{
+			found = true;
+
+			pg_log(ctx, PG_WARNING,
+				   "libpq env var %-20s is currently set to: %s\n", option->envvar, value);
+		}
+
+		option++;
+	}
+
+	/* Free the memory that libpq allocated on our behalf */
+	PQconninfoFree(start);
+
+	if (found)
+		pg_log(ctx, PG_FATAL,
+			   "libpq env vars have been found and listed above, please unset them for pg_upgrade\n");
+}