Some basic checks we make were placed early enough in generated
configure script when using autoconf 2.5X versions. Newer autoconf
versions expand these checks much further into the configure script,
rendering them useless. Using XC_CONFIGURE_PREAMBLE fixes placement
of early intended checks across all our autoconf supported versions.
Tested with:
buildconf: autoconf version 2.69
buildconf: autom4te version 2.69
buildconf: autoheader version 2.69
buildconf: automake version 1.13.1
buildconf: aclocal version 1.13.1
buildconf: libtool version 2.4
buildconf: GNU m4 version 1.4.16
Provide a 'traceable' AC_CONFIG_MACRO_DIR definition only when using
an autoconf version that does not provide it, instead of what we were
doing up to now of providing and overriding AC_CONFIG_MACRO_DIR for
all autoconf versions.
Take in account that POSIX standard Issue 7 drops h_errno support. Now, we also
consider getaddrinfo() to be thread-safe when (_POSIX_C_SOURCE >= 200809L) or
(_XOPEN_SOURCE >= 700) independently of whether h_errno exists or not.
Take in account that h_errno might be a modifiable lvalue not defined as
a C preprocessor macro.
Issue: When building a 32bit target with large file support HP-UX
<sys/socket.h> header file may simultaneously provide two different
sets of declarations for sendfile and sendpath functions, one with
static and another with external linkage. Given that we do not use
mentioned functions we really don't care which linkage is the
appropriate one, but on the other hand, the double declaration emmits
warnings when using the HP-UX compiler and errors when using modern
gcc versions resulting in fatal compilation errors.
Mentioned issue is now fixed as long as we don't use sendfile nor
sendpath functions.
I can see that recvfrom() in ares_process.c many times is called with
'udp_socket' == ARES_SOCKET_BAD. The code takes care not to call
recv/recvfrom with ARES_SOCKET_BAD in the outer-loop. So should the
inner-loop.
Currently it is unknown if there is any version of clang that
actually supports -Wstrict-aliasing. What is known is that there
are several that don't support it.
I need to do SOA queries, so here is a parser for them.
- ares_soa_reply: new struct
- ares_malloc_data/ares_free_soa: ARES_DATATYPE_SOA_REPLY
- ares_parse_soa_reply: actual function
The UDP and TCP port are stored in network byte order in the
ares_channeldata, but are passed in to ares_init_options() in host byte
order. Thus we must return them from ares_save_options() in host byte
order too, or a duplicated channel will convert them again, leading to a
nonfunctional channel and a mysterious connection refused error from
ares_gethostbyname(). This breaks ares_dup(), thus the curl easy API
when c-ares is used by curl, and thus all the curl easy API's users.
