When reading/writing block devices, Cygwin emulates Linux, providing
a byte-exact file position, albeit the underlying device drivers don't.
Unfortunately this only worked correctly for reading. The raw_write
method failed to revalidate the buffer after the read-modify-write
cycle in case len is not a multiple of the sector length. This in
turn resulted in lseek reporting a wrong file pointer.
Also, fix a condition for invalidating the buffer after writing from
a remaining read buffer.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Rounddown incoming addr on a page boundary. Without this, we may end
up with a fork error for private, anonymous maps. The reason is, we
use VirtualAlloc in this case which will potentially overcommit if
addr is not on a page boundary. This isn't taken into account in
bookkeeping, but fixup_mmaps_after_fork will eventually stumble over
this when trying to reproduce the copy-on-write pages: VirtualQuery
returns a region reaching beyond the supposedly allocated address
range and from there it goes downhill.
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
* change memcpy to internal _memcpy not setting the return value in %rax
* implement all memcpy-like functions as caller to _memcpy, setting %rax
to correct return value beforehand. This is possible because _memcpy
does not use %rax at all
Signed-off-by: Corinna Vinschen <corinna@vinschen.de>
Yaakov Selkowitz
Brian Inglis
Corinna Vinschen
Mark Geisert
Jon Turney