Make UDP sockets non-blocking. I've confirmed that at least on Linux 2.4 a
read event can come back from poll() on a valid SOCK_DGRAM socket but
recv(2) will still block. This patch doesn't ignore EAGAIN in
read_udp_packets(), though maybe it should. (This patch was edited by Daniel
Stenberg and a new configure test was added (imported from curl's configure)
to properly detect what non-blocking socket approach to use.)
Basically in loops like handle_errors(), 'query->next' was assigned a local
variable and then query was referenced after the memory was freed by
next_server(). I've changed that so next_server() and end_query() returns the
next query. So callers should use this ret-value.
The next problem was that 'server->tcp_buffer_pos' had a random value at entry
to 1st recv() (luckily causing Winsock to return ENOBUFS).
I've also added a ares_writev() for Windows to streamline the code
a bit more.
check for ssize_t to make it possible to use that when receiving the send()
error code. This is necessary to prevent compiler warnings on some systems.
- Made configure create config.h, and all source files now include setup.h that
might include the proper config.h (or a handicrafted alternative).
- Switched to 'ares_socket_t' type for sockets in ares, since Windows don't
use 'int' for that.
- automake-ified and libool-ified c-ares. Now it builds libcares as a shared
lib on most platforms if wanted. (This bloated the size of the release
archive with another 200K!)
- Makefile.am now uses Makefile.inc for the c sources, h headers and man
pages, to make it easier for other makefiles to use the exact same set of
files.
- Adjusted 'maketgz' to use the new automake magic when building distribution
archives.
