Subject: Re: [PATCH 1/2] archive-tar: write extended headers for file sizes >= 8GB

From: René Scharfe <[email-masked]>
Date: Tue, 21 Jun 2016 22:57:43 +0200

Am 21.06.2016 um 22:42 schrieb René Scharfe:
> The value 120 is magic; we need it to pass the tests.  That's
> because prepare_header() is used for building extended header
> records as well and we don't create extended headers for extended
> headers (not sure if that would work anyway), so they simply
> vanish when they're over the limit as their size field is set to
> zero.

So how about something like this to make sure extended headers are
only written for regular files and not for other extended headers?
---
 archive-tar.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/archive-tar.c b/archive-tar.c
index ed562d4..f53e61c 100644
--- a/archive-tar.c
+++ b/archive-tar.c
@@ -199,7 +199,7 @@ static void prepare_header(struct archiver_args *args,
 {
 	xsnprintf(header->mode, sizeof(header->mode), "%07o", mode & 07777);
 	xsnprintf(header->size, sizeof(header->size), "%011lo",
-		  S_ISREG(mode) ? ustar_size(size) : 0);
+		  S_ISREG(mode) ? size : 0);
 	xsnprintf(header->mtime, sizeof(header->mtime), "%011lo",
 		  ustar_mtime(args->time));
 
@@ -240,7 +240,7 @@ static int write_tar_entry(struct archiver_args *args,
 	struct ustar_header header;
 	struct strbuf ext_header = STRBUF_INIT;
 	unsigned int old_mode = mode;
-	unsigned long size;
+	unsigned long size, size_in_header;
 	void *buffer;
 	int err = 0;
 
@@ -299,12 +299,14 @@ static int write_tar_entry(struct archiver_args *args,
 			memcpy(header.linkname, buffer, size);
 	}
 
-	if (S_ISREG(mode) && ustar_size(size) != size)
+	size_in_header = S_ISREG(mode) ? ustar_size(size) : size;
+	if (size_in_header != size)
 		strbuf_append_ext_header_uint(&ext_header, "size", size);
+
 	if (ustar_mtime(args->time) != args->time)
 		strbuf_append_ext_header_uint(&ext_header, "mtime", args->time);
 
-	prepare_header(args, &header, mode, size);
+	prepare_header(args, &header, mode, size_in_header);
 
 	if (ext_header.len > 0) {
 		err = write_extended_header(args, sha1, ext_header.buf,
-- 
2.9.0