From fe68b9a3f7a335bb0ee0d9bd5f07a121416f337d Mon Sep 17 00:00:00 2001
From: Con Kolivas <kernel@kolivas.org>
Date: Sat, 12 Mar 2011 11:17:11 +1100
Subject: [PATCH] Institute writing and reading of 0.6 file format for
 compress/decompress.

---
 lrzip.c         | 17 ++++++++++-------
 lrzip_private.h |  3 ++-
 stream.c        | 23 +++++++++++++++++++++--
 3 files changed, 33 insertions(+), 10 deletions(-)

diff --git a/lrzip.c b/lrzip.c
index a6ad4a0..a1ee5a8 100644
--- a/lrzip.c
+++ b/lrzip.c
@@ -46,7 +46,7 @@ void write_magic(rzip_control *control, int fd_in, int fd_out)
 {
 	struct timeval tv;
 	struct stat st;
-	char magic[40];
+	char magic[39];
 	int i;
 
 	memset(magic, 0, sizeof(magic));
@@ -92,12 +92,13 @@ void write_magic(rzip_control *control, int fd_in, int fd_out)
 
 void read_magic(rzip_control *control, int fd_in, i64 *expected_size)
 {
-	char magic[40];
+	char magic[39];
 	uint32_t v;
 	int md5, i;
 
-	memset(magic, 0, 40);
-	if (unlikely(read(fd_in, magic, sizeof(magic)) != sizeof(magic)))
+	memset(magic, 0, sizeof(magic));
+	/* Initially read only <v0.6x header */
+	if (unlikely(read(fd_in, magic, 24) != 24))
 		fatal("Failed to read magic header\n");
 
 	*expected_size = 0;
@@ -117,6 +118,8 @@ void read_magic(rzip_control *control, int fd_in, i64 *expected_size)
 	} else {
 		memcpy(expected_size, &magic[6], 8);
 		if (control->major_version == 0 && control->minor_version > 5) {
+			if (unlikely(read(fd_in, magic + 24, 15) != 15))
+				fatal("Failed to read magic header\n");
 			if (magic[22] == 1)
 				control->encrypt = 1;
 			memcpy(&control->secs, &magic[23], 8);
@@ -635,7 +638,7 @@ void compress_file(rzip_control *control)
 					 * Spares a compiler warning
 					 */
 	int fd_in, fd_out;
-	char header[24];
+	char header[39];
 
 	memset(header, 0, sizeof(header));
 
@@ -708,13 +711,13 @@ void compress_file(rzip_control *control)
 
 	preserve_perms(control, fd_in, fd_out);
 
-	/* write zeroes to 24 bytes at beginning of file */
+	/* Write zeroes to header at beginning of file */
 	if (unlikely(write(fd_out, header, sizeof(header)) != sizeof(header)))
 		fatal("Cannot write file header\n");
 
 	rzip_fd(control, fd_in, fd_out);
 
-	/* write magic at end b/c lzma does not tell us properties until it is done */
+	/* Wwrite magic at end b/c lzma does not tell us properties until it is done */
 	write_magic(control, fd_in, fd_out);
 
 	if (STDOUT)
diff --git a/lrzip_private.h b/lrzip_private.h
index bff5b2f..8fd9762 100644
--- a/lrzip_private.h
+++ b/lrzip_private.h
@@ -180,7 +180,7 @@ struct rzip_control {
 	int encrypt;
 	i64 secs;
 	i64 usecs;
-	int eof;
+	unsigned char eof;
 	md5_ctx ctx;
 	i64 md5_read; // How far into the file the md5 has done so far
 };
@@ -206,6 +206,7 @@ struct stream_info {
 	i64 initial_pos;
 	i64 total_read;
 	i64 ram_alloced;
+	i64 size;
 	long thread_no;
 	long next_thread;
 	int chunks;
diff --git a/stream.c b/stream.c
index 2fc7cad..c07e177 100644
--- a/stream.c
+++ b/stream.c
@@ -818,7 +818,7 @@ void *open_stream_out(rzip_control *control, int f, unsigned int n, i64 chunk_li
 	if (unlikely(!sinfo))
 		return NULL;
 
-	sinfo->bufsize = limit = chunk_limit;
+	sinfo->bufsize = sinfo->size = limit = chunk_limit;
 
 	sinfo->chunk_bytes = cbytes;
 	sinfo->num_streams = n;
@@ -917,7 +917,6 @@ void *open_stream_in(rzip_control *control, int f, int n)
 
 	sinfo->num_streams = n;
 	sinfo->fd = f;
-	sinfo->initial_pos = lseek(f, 0, SEEK_CUR);
 
 	sinfo->s = calloc(sizeof(struct stream), n);
 	if (unlikely(!sinfo->s)) {
@@ -928,6 +927,21 @@ void *open_stream_in(rzip_control *control, int f, int n)
 	sinfo->s[0].total_threads = 1;
 	sinfo->s[1].total_threads = total_threads - 1;
 
+	if (control->major_version == 0 && control->minor_version > 5) {
+		/* Read in flag that tells us if there are more chunks after
+		 * this */
+		if (unlikely(read_u8(f, &control->eof))) {
+			print_err("Failed to read eof flag in open_stream_in\n");
+			goto failed;
+		}
+		/* Read in the expected chunk size */
+		if (unlikely(read_i64(f, &sinfo->size))) {
+			print_err("Failed to read in chunk size in open_stream_in\n");
+			goto failed;
+		}
+	}
+	sinfo->initial_pos = lseek(f, 0, SEEK_CUR);
+
 	for (i = 0; i < n; i++) {
 		uchar c;
 		i64 v1, v2;
@@ -1060,6 +1074,11 @@ retry:
 		/* Write chunk bytes of this block */
 		write_u8(ctis->fd, ctis->chunk_bytes);
 
+		/* Write whether this is the last chunk, followed by the size
+		 * of this chunk */
+		write_u8(ctis->fd, control->eof);
+		write_i64(ctis->fd, ctis->size);
+
 		/* First chunk of this stream, write headers */
 		ctis->initial_pos = lseek(ctis->fd, 0, SEEK_CUR);