Coverity gets antsy that we were checking wsi->a.protocol for NULL earlier
then start using it... explicitly bail if it's NULL before we start using
it.
This patch adapts the recent change about serializing the number of
simultaneous tls handshakes allowed to 1, so you can set the number in the
context creation info, and the accounting for it is handled by counters
same as the overally tls restriction.
The name of the context info var to control it changes to simultaneous_ssl_handshake_restriction
which is now a count, the default 0 means no limit.
The count rejects tls connection attempts when the tls borrow is attempted,
and separately hands back the hs borrow from the tls borrow when the
connection attempt fails or succeeds.
Let's improve the details returned in CLIENT_CONNECTION_ERROR in string so
we can get more clues about the problem. Create dynamic strings that
classify at what step the error happened, and add dynamic info like the
errno.
This adds an indication of dns disposition to the conmon results,
and for http, if it gets that far a protocol-specific indication
of http response code.
lws_tls_restrict_borrow() returns error when tls restriction limit is
reached. However lws_ssl_close() still calls lws_tls_restrict_return()
to decrease simultaneous_ssl. Thus LWS accepts more than allowed ssl
links, making simultaneous_ssl_restriction useless.
Fix it by tracking lws_tls_restrict_borrow() return value and only
calling lws_tls_restrict_return() if lws_tls_restrict_borrow() is
successful.
Add -Wextra (with -Wno-unused-parameter) to unix builds in addition to
-Wall -Werror.
This can successfully build everything in Sai without warnings / errors.
This causes the blocking dns lookup to treat EAI_NONAME as immediately
fatal, this is usually caused by an assertive NXDOMAIN from the DNS server
or similar.
Not being able to reach the server should continue to retry.
In order to make the problem visible, it reports the situation using
CLIENT_CONNECTION_ERROR, even though it is still inside the outer client
creation call.
