Most of the unsigned DMAP types were missing and assignments were incorrect
between signed and unsigned types. Fix all of this, and add (preliminary)
support for the new types.
This code in daap_reply_songlist_generic() is redundant with code
in (new) dmap_add_field() and can be removed, with a tweak: we must
ensure the val integer is always 0 if not used to override a value in
the transcoding case.
lseek() returns an off_t and not an int, using an int to store and
test the return value means we'll error out when the position in the file
gets past INT_MAX.
The pairing hash actually uses standard MD5, so let's simplify the
code by using a standard MD5 implementation. Now that function is
readable and understandable by mere mortals.
Thanks to Jeff Sharkey for posting that simplified version.
eventfd has less overhead than a pipe, works as a counter and uses a
single fd. Use it on Linux if available (that should be pretty much
always given the glibc and kernel requirements).
512k might be a bit too much, as it can take time to read 512k from the
filesystem (and we're using a blocking read) or from the decoder. Going
down to 64k will make this more manageable and improve the response time
when streaming to multiple clients at the same time.
evbuffer_read() is really meant to read from sockets and not regular
files. It also looks like evbuffer_read() was causing issues with large
files, locking up a little below 2 GB for an unknown reason (couldn't
reproduce).
Try to be a bit more strict about integer types, use off_t or int64_t for
file size and file offsets.
Replace safe_ato*() by safe_atoi32() and safe_atoi64(), fix integer types
at call sites to match.
Hinting the OS about our behaviour shouldn't make a big difference in
performance but it will help the OS manage its disk cache and can reduce
memory pressure on small systems.
DAAP queries from Remote won't need HTTP authentication as they all
require a valid session-id; Remote can only obtain a valid session-id
if its pairing-guid is known to us (it did pair successfully with us).
Stock evhttp has no means to detect when an incoming connection gets
closed by the client; it will notice the connection has gone down only
when sending back a reply.
For DAAP update requests working as a push mechanism with an HTTP request
stalled by the server until there actually is an update available, we need
to be notified when a connection goes down so we can perform proper cleanup
and not retain memory.
Do so by extending the close detection mechanism used for outgoing connections
and the connection failure callback we already have in place for streaming.
Get rid of strlcpy() and its implementation entirely, it doesn't buy anything
over snprintf(). Use evutil_snprintf() so as to match the rest of the code.
