Several documentation callbacks (doc/0 and mod_doc/0) are implemented
and `ejabberdctl man` command is added to generate a man page. Note
that the command requires a2x to be installed (which is a part of
asciidoc package).
When module's options were updated (e.g. by reloading ejabberd.yml)
and, later, the module's process crashed, gen_mod supervisor
restarts the process with outdated options. This is now fixed.
The header consisted of too many unrelated stuff and macros misuse.
Some stuff is moved into scram.hrl and type_compat.hrl.
All macros have been replaced with the corresponding function calls.
TODO: probably type_compat.hrl is not even needed anymore since
we support only Erlang >= OTP 17.5
Due to historical reasons, ejabberd loads the whole file/data
into the memory when serving an HTTP request. This is now improved:
1) For GET requests ejabberd uses sendfile(2) if the underlying
connection is HTTP and falls back to read/write loop with 64kb
buffer for HTTPS connections. This type of requests are handled
by mod_http_fileserver, mod_http_upload, ejabberd_captcha, etc
2) POST requests are now limited to 20Mb and are fully downloaded
into the memory for further processing (by ejabberd_web_admin,
mod_bosh, etc)
3) PUT requests (e.g. for mod_http_upload) are handled by read/write
loop with 64kb buffer
The callback is supposed to provide known options and their default
values, as long as the documentation. Passing default values into
get_mod functions is now deprecated: all defaults should be provided
by the Mod:mod_options/1 callback.
The changes are very similar to those from previous commit:
* Now there is no need to pass validating function in
gen_mod:get_opt() and gen_mod:get_module_opt() functions,
because the modules' configuration keeps already validated values.
* New functions gen_mod:get_opt/2 and gen_mod:get_module_opt/3 are
introduced.
* Functions gen_mod:get_opt/4 and get_module_opt/5 are deprecated.
If the functions are still called, the "function" argument is
simply ignored.
* Validating callback Mod:listen_opt_type/1 is introduced to validate
listening options at startup.
