From 6e31fc621ed71b8cfa52c584a5e2f2831326bea3 Mon Sep 17 00:00:00 2001
From: Con Kolivas <kernel@kolivas.org>
Date: Mon, 9 Mar 2015 11:46:24 +1100
Subject: [PATCH] Cache the chunk bytes value to avoid setting it on each
 read_header call

---
 lrzip_private.h |  1 +
 runzip.c        | 14 ++++++++------
 2 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/lrzip_private.h b/lrzip_private.h
index 32648f8..d5cad4c 100644
--- a/lrzip_private.h
+++ b/lrzip_private.h
@@ -444,6 +444,7 @@ struct rzip_control {
 	void (*log_cb)(void *data, unsigned int level, unsigned int line, const char *file, const char *func, const char *format, va_list);
 	void *log_data;
 
+	char chunk_bytes;
 	struct sliding_buffer sb;
 	void (*do_mcpy)(rzip_control *, unsigned char *, i64, i64);
 	void (*next_tag)(rzip_control *, struct rzip_state *, i64, tag *);
diff --git a/runzip.c b/runzip.c
index 20e54ea..0a0e630 100644
--- a/runzip.c
+++ b/runzip.c
@@ -1,5 +1,5 @@
 /*
-   Copyright (C) 2006-2012 Con Kolivas
+   Copyright (C) 2006-2015 Con Kolivas
    Copyright (C) 1998-2003 Andrew Tridgell
 
    This program is free software; you can redistribute it and/or modify
@@ -139,16 +139,12 @@ static i64 seekto_fdinend(rzip_control *control)
 
 static i64 read_header(rzip_control *control, void *ss, uchar *head)
 {
-	int chunk_bytes = 2;
 	bool err = false;
 
-	/* All chunks were unnecessarily encoded 8 bytes wide version 0.4x */
-	if (control->major_version == 0 && control->minor_version == 4)
-		chunk_bytes = 8;
 	*head = read_u8(control, ss, 0, &err);
 	if (err)
 		return -1;
-	return read_vchars(control, ss, 0, chunk_bytes);
+	return read_vchars(control, ss, 0, control->chunk_bytes);
 }
 
 static i64 unzip_literal(rzip_control *control, void *ss, i64 len, uint32 *cksum)
@@ -309,6 +305,12 @@ static i64 runzip_chunk(rzip_control *control, int fd_in, i64 expected_size, i64
 	if (unlikely(!ss))
 		failure_return(("Failed to open_stream_in in runzip_chunk\n"), -1);
 
+	/* All chunks were unnecessarily encoded 8 bytes wide version 0.4x */
+	if (control->major_version == 0 && control->minor_version == 4)
+		control->chunk_bytes = 8;
+	else
+		control->chunk_bytes = 2;
+
 	while ((len = read_header(control, ss, &head)) || head) {
 		i64 u;
 		if (unlikely(len == -1))