Bug#314334: apt: APT doesn't work on filesystems without shared writable mmap(), like JFFS2.

[Matt Zimmerman <mdz@debian.org>]

severity 314334 wishlist
thanks

On Wed, Jun 15, 2005 at 01:14:13PM -0600, Matthew S. Wood wrote:
> Package: apt
> Version: 0.5.28.6
> Severity: important
> Tags: patch
> 
> APT doesn't work on filesystems which don't support shared writable mmap.
> This is significant for hand-held devices which use NAND flash as a data
> store.  These devices typically use a filesystem like JFFS2, which lacks
> shared writable mmap support.
> 
> The attached patch optionally implements [at compile time] support for
> mmap() emulation within APT.  In order for this support to properly
> function, a modification to the FileFd class was required.  This
> modification makes the FileFd class keep a cache of open files, such that
> if two contexts both hold the same file descriptor, the file descriptor
> isn't closed until both FileFd destructors are called.

Thanks for the patch. 

I am hesitant to complicate the code in this way in order to implement such
a workaround, though (especially with preprocessor macros).  I expect it
would be more gracefully implemented as a derived class.  What do you think?

-- 
 - mdz