This adds support for allow-deny kind of rules with the matchfile API.

See: #2119

ban and allow file support has been moved into a generic implementation
that can be re-used by later code such as proxy matching or other
blacklisting.
See: #1959

When unset no default is used but the feature is disabled.
(The Shoutcast listen socket is not opened at all.)

Thanks to Jeremiah Rogers for pointing out.

This fixes a bug that could cause the global listener count of Icecast to
be negative. This was caused due to wrong handling of errors in the
format_prepare_headers function.

Fixes: #2199

Thanks a lot to Simeon Völkel (0xBD4E031CDB4043C9) for reporting
and investigating the bug.

This fixes some possible segfaults that could happen if the header
(re)allocation fails.

Also adjust formatting a bit, kill some trailing spaces.

Fixes: #2198

If there is a single "-" or it is only accompanied by whitespace, then
it wouldn't get escaped as it was detected as as a number. This would
produce invalid JSON.
This makes the numbers part ignore such and thus ensures it gets escaped
as text.

There might be other corner cases related to number parsing, this should be investigated.

https://github.com/doekman/xml2json-xslt/pull/20

 Some numeric values would not get formatted to valid JSON. This
 incorporates the suggestions from issue #15.

Also fixed whitespace of original patch.
Additional fix for related issue will follow.

This (hopefully) corrects the usage of realloc() as free().
This patch is part of the series based on Denis Denisov's input.

This let util_url_escape() handle NULL passed as parameter.
In case the parameter is NULL it will also return NULL.

This patch also does some cleanup of the code such as migration
away from int and thus avoiding future failtures.

This is a re-apply of 3baa4e46
as git refuses to cherry-pick.

This is a first commit to correct minor problmes reported by
Denis Denisov. There is likely another commit to correct some more
such problems.

Thank you Denis Denisov.

This cleans the libcurl usage up a bit. It moves common code used
to interact with libcurl into a single new file curl.[ch].

Notes:
* It does not alter any features nor fixes any bugs.
* Thew REVIEW about strdup(self->url) in event_url.c as been processed.
  According to the manpage for curl_easy_setopt()/CURLOPT_URL
  there is no need for us to copy.
* URL Auth as well as URL triggers have sent ICECAST_VERSION_STRING
  as User-Agent:, this has be corrected to what is set in the config
  file.
* As curl.c is now a single point for setting parameters all the TLS
  parameters should be reviewed and set (based on config).

Please test!

The parent element for <event> was renamed from <kartoffelsalat>
to <event-bindings> as discussed on the mailinglist and on IRC.

This patch adds support for history for ICY based streams.
Of cause this has the same limits for metedata as ICY has.

See: #766

This adds a <max-history> config option to the <mount> section.
Default is a history size of 4.

See: #766

The playlist truncation (may_tracks) was off by one.
This fixes the problem.

This allows to store a history of played songs along the source
object and report it as part of the status XML.

Additional work needs to be done to make this configurable.
Also format_mp3.c needs work to support this.

A generic song changed handler should be implemented to handle this
in a nice way.
That one should also be the point to call logging_playlist().

See: #766

This adds the operation mode "strict". It does not yet have
any specific features and alias the "normal" mode.
This change is mostly to make the setting of "strict" valid
so it can be used already.

As we do not support any SSL version but TLS this renames
all TLS related config options. Docs still need to be updated.
Close still uses 'ssl' internally e.g. for variable names.
This should be changed on a later patch.

 * Reworded many log messages for better understanding.
 * Adjusted some version targets as we won't have a 2.4.2 release.
 * Added some FIXME comments

Fix variable alignment if necessary.