From 90f446f9b04ab820a99b9408e68c01dc6b57056c Mon Sep 17 00:00:00 2001

From: rpm-build <rpm-build>

Date: Mon, 28 Jul 2014 08:10:10 +0200

Subject: [PATCH 2/9] vfat-like FS & sparse (still downstream)

Fix extracting sparse files to a file system like vfat, when

ftruncate may fail to grow the size of a file.  Still downstram,

(do we need this now? ftruncate & vfat works is now OK).

Resolves: #179507

Upstream bugreport:

http://lists.gnu.org/archive/html/bug-tar/2006-02/msg00000.html

---

 src/system.c | 19 ++++++++++++++++++-

 1 file changed, 18 insertions(+), 1 deletion(-)

diff --git a/src/system.c b/src/system.c

index 9414233..37e9a3e 100644

--- a/src/system.c

+++ b/src/system.c

@@ -243,8 +243,25 @@ sys_compare_links (struct stat *link_data, struct stat *stat_data)

 int

 sys_truncate (int fd)

 {

+  struct stat st;

   off_t pos = lseek (fd, (off_t) 0, SEEK_CUR);

-  return pos < 0 ? -1 : ftruncate (fd, pos);

+

+  if ( pos < 0) 

+    return -1;

+

+  if ( ftruncate(fd, pos) && errno == EPERM ) {

+    /* wrapper around ftruncate:

+     * ftruncate may fail to grow the size of a file with some OS and filesystem

+     * combinations. Linux and vfat/fat is one example. If this is the case do

+     * a write to grow the file to the desired length.

+     */

+    if( (fstat( fd, &st ) == -1) || 

+        (st.st_size >= pos)  ||

+        (lseek( fd, pos - 1, SEEK_SET) == (off_t)-1) ||

+        (write( fd, "\0", 1) == -1) )

+	return -1;

+  }

+  return 0;

 }

 /* Return nonzero if NAME is the name of a regular file, or if the file

-- 

1.9.3