Clean up pg_basebackup libpq usage

sfrost · sfrost · commit 2f397a08de49 · 2013-07-15T11:27:20.000-04:00
When using libpq, it's generally preferrable to just use the strings
which are in the PQ structures instead of copying them out, so do
that instead in BaseBackup(), eliminating the strcpy()'s used there.

Also, in ReceiveAndUnpackTarFile(), check the string length for the
directory returned by the server for the tablespace path.
diff --git a/src/bin/pg_basebackup/pg_basebackup.c b/src/bin/pg_basebackup/pg_basebackup.c
@@ -509,7 +509,15 @@ ReceiveAndUnpackTarFile(PGconn *conn, PGresult *res, int rownum)
 	if (PQgetisnull(res, rownum, 0))
 		strcpy(current_path, basedir);
 	else
+	{
+		if (PQgetlength(res, rownum, 1) >= MAXPGPATH)
+		{
+			fprintf(stderr, _("%s: received invalid directory (too long): %s"),
+					progname, PQgetvalue(res, rownum, 1));
+			disconnect_and_exit(1);
+		}
 		strcpy(current_path, PQgetvalue(res, rownum, 1));
+	}
 
 	/*
 	 * Make sure we're unpacking into an empty directory
@@ -814,8 +822,6 @@ BaseBackup(void)
 	char		current_path[MAXPGPATH];
 	char		escaped_label[MAXPGPATH];
 	int			i;
-	char		xlogstart[64];
-	char		xlogend[64];
 	int			minServerMajor,
 				maxServerMajor;
 	int			serverMajor;
@@ -877,11 +883,9 @@ BaseBackup(void)
 				progname);
 		disconnect_and_exit(1);
 	}
-	strcpy(xlogstart, PQgetvalue(res, 0, 0));
 	if (verbose && includewal)
-		fprintf(stderr, "xlog start point: %s\n", xlogstart);
+		fprintf(stderr, "xlog start point: %s\n", PQgetvalue(res, 0, 0));
 	PQclear(res);
-	MemSet(xlogend, 0, sizeof(xlogend));
 
 	/*
 	 * Get the header
@@ -962,9 +966,8 @@ BaseBackup(void)
 				progname);
 		disconnect_and_exit(1);
 	}
-	strcpy(xlogend, PQgetvalue(res, 0, 0));
 	if (verbose && includewal)
-		fprintf(stderr, "xlog end point: %s\n", xlogend);
+		fprintf(stderr, "xlog end point: %s\n", PQgetvalue(res, 0, 0));
 	PQclear(res);
 
 	res = PQgetResult(conn);
