Moved the blocking state machine to the disconnect functions so that the
logout / quit functions are only responsible for sending the actual
command needed to logout or quit.
Additionally removed the hard return on failure.
Some state changes would be performed after a failure test that
performed a hard return, whilst others would be performed within a test
for success. Updated the code, for consistency, so all instances are
performed within a success test.
Removed this pointer to a downloaded bytes counter because it was set in
smtp_init() to point to the same variable the transfer functions keep
the count in (k->bytecount), effectively making the code in transfer.c
"*k->bytecountp = k->bytecount" a no-op.
Removed user and passwd from the SMTP struct as these cannot be set on
a per-request basis and are leftover from legacy FTP code.
Changed some comments still using FTP terminology.
... since they're not used by the easy interface really, I wanted to
remove the association. Also, I unified the pingpong statemachine driver
into a single function with a 'wait' argument: Curl_pp_statemach.
Reworked the pp->endofresp() function so that the conndata, line and
line length are passed down to it just as with Curl_client_write()
rather than each implementation of the function having to query
these values.
Additionally changed the int return type to bool as this is more
representative of the function's usage.
Corrected the order of the upgrade_tls() functions and moved the handler
upgrade and getsock() functions out from the middle of the state related
functions.
Added honoring of the tls_supported flag when starting a TLS upgrade
rather than unconditionally attempting it. If the use_ssl flag is set
to CURLUSESSL_TRY and the server doesn't support TLS upgrades then the
connection will continue to authenticate. If this flag is set to
CURLUSESSL_ALL then the connection will complete with a failure as it
did previously.
Follow up fix to commit 62bd217464 to cater for servers that don't
respond with a 250 in their EHLO responses. Additionally updated the
SMTP tests to respond with a 250 response code as per RFC5321.
Fixed a small issue where smtp_endofresp() would look for capabilities
in the description part of a failure response. In theory a server
shouldn't respond with SIZE or AUTH in an EHLO command's failure
response but if it did then capabilities would be unnecessarily set
before eventually failing.
Changed the SMTP_AUTH_PASSWD state constant to SMTP_AUTH_LOGIN_PASSWD to
better describe the state as the second part of an AUTH LOGIN command,
as well as for consistency with the imap and pop3 modules.
Minor code tidy up to add comments similar to those used in the pop3
and imap end of resp functions, in order to assist anyone reading the
code and highlight the similarities between each of these protocols.
smtp_state_upgrade_tls() would attempt to incorrectly complete the
upgrade to smtps and start the EHLO command if
Curl_ssl_connect_nonblocking() returned a failure code and if ssldone
was set to TRUE. This would only happen when a non-blocking API hadn't
been provided by the SSL implementation and curlssl_connect() was
called underneath.
