imapc: Remove root_sep_lookup_failed cache The auth_failed_* should already be enough for this. This removal also fixes the storage error message to be auth_failed_reason when possible.

global: unsigned int:1 -> bool:1 perl -i -pe 's/unsigned int ([^,:;]+):1;/bool $1:1;/' **/*.[ch]

imapc: If root separator lookup fails, fail all further lookups. We already returned a potentially wrong separator (since there's no way to return error), so we don't want to continue and possibly make things worse.

imapc: Fixed escaping/unescaping mailbox names. This fixes accessing mailbox names with '%' (the escape_char). It also fixes local namespace separator being different from the remote separator.

imapc: Cache LIST replies for a while to be able to immediately ask for mailbox flags/existence. Besides giving better performance, this will fix bugs in some servers where LISTing a single mailbox doesn't necessarily return it. (In this case a mailbox named "in" wasn't returned, but I think Dovecot has had bugs related to this also.)

imapc: Reorganize code so that imapc_list works without imapc_storage. Most importantly fixes crashes when imapc_list is trying to lookup hierarchy separator before storage is created.

imapc: Code cleanup: Don't access imapc settings via storage.

imapc: If imapc isn't the inbox=yes namespace, do the login and initial LIST in background.

Reverted 269104a0821b (Build imapc and pop3c always as plugins.) This is no longer needed now that lib-ssl-iostream can be linked without linking openssl.

Build imapc and pop3c always as plugins. This avoids having to link openssl library to all binaries that use lib-storage. It appears that simply by linking with openssl causes each such process to use 100-200 kB of more memory. With 10k imap processes this is 1-2 GB of wasted memory. The imapc and pop3c are still registered as stubs, and their plugins are automatically loaded when needed.

imapc: Fixed mailbox_exists() to actually work. This fixes problems with subscribing to mailboxes.

imapc: Connect to server immediately at startup and lookup hierarchy separator. If connecting to server fails, this makes it fail earlier. Also we don't have to worry about what to do later if hierarchy separator lookup fails.

imapc: Initial support for local index files.

imapc: Mailbox listing code works now perfectly.

imapc: Code cleanups and fixes.

imapc: Added support for LIST/LSUB.