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# unbound-adblock 0.6 Release Notes / Changelog 
# Copyright 2018-2021 Jordan Geoghegan <jordan@geoghegan.ca>
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The unbound-adblock v0.6 release features a number of usability, efficiency and performance improvements.

Release Notes:

# Significant efficiency and performance improvements accross the board:

- Improvements to URL Fetching:
	* Add support for aria2c HTTP/FTP fetch utility.
	* Add support for HTTP compression when using aria2c, curl or wget for fetching block lists.
	* We now opportunistically make use of the best available URL fetch utility, with overrides enabled via long options.
	* aria2c, curl and wget are now fed URLs over a pipe, which eliminates issues with argument length limits and maximizes potential socket and cache reuse.
	* Curl now properly follows redirects.
	* Enforce strict timeout limits to avoid hangs or infinite reads when fetching blocklists (functionality varies amoung supported URL fetch utilities).
	* FreeBSD/DragonflyBSD "fetch" utility now supports custom user agents.
	* Explicitely disable URL globbing.


- Use parallelism/concurrency where appropriate:
	* Blocklist URLs can now be fetched in parallel thanks to aria2c.
	* Blocklist parsing is now performed in parallel.


- New Features:
	* Add support for custom DNS blocking response codes: NXDOMAIN, NODATA, REFUSED and NULL.
	* Add '-C' flag to specify a configuration file to load.
	* Add '-P' flag to control maximum number of parallel processes.
	* Add '-U' option to specify HTTP user agent.
	* Add '-f' flag to load blocklist from local file system.
	* Add '-o' long options to set awk/grep/fetch utility preference. Please see manpage for details.
	* Add '-o print-debug' to print debugging information and statistics.


- To make things faster, do less work:
	* Address parser is now less picky about list formatting. This allows for a broader range of blocklist formats to be ingested.
	* Mixed lists are now supported: Blocklists may now be comprised of any combination of supported blocklist formats, with no format declarations required.
	* Changes to the blocklist parsing/handling code has allowed for the removal of a bunch of superflous code.
	* As a result of the address parser refactoring, significant performance gains should be expected.
	* Multiple internal functions have been adjusted to avoid fork+exec and subshell overhead.
	* We now make use of modern shell features to eliminate numerous potential footguns.


- Portability Improvements:
	* Communication with Unbound now occurs exclusively via unbound-control. This makes portability much easier, and allows for the removal of a bunch of code.
	* By default we now write generated blocklist data to symlink '/var/unbound-adblock/block.db'. This makes portability much easier, and allows for the removal of a bunch of code.


- Configuration Changes:
	* Use of 'set -o pipefail' is now required. This means you'll need a modern oksh, bash, zsh or ksh93 shell to run unbound-adblock.
	* OS type decleration with the '-O' flag has been removed, as OS type is now auto-detected.
	* The '-o [no-]whitelist flags were renamed to '-o [no-]custom-filter' to reflect the features versatility.
	* Compressed lists may now only be declared in the "Custom Lists" section from a config file specified with '-C'.
	* Use of doas/sudo is now determined automatically, with doas being preferred. Use long options to override.
	---
	* Remove all reference to /etc/hosts and domain-only list formats as they are now processed identically and 
	  no longer require differentiation from the users perspective. As a result, the '-t' and '-d' options have been
	  removed entirely, and the '-l' and '-u' options repurposed. The '-l' option is now used to reference a path to a list of URLs
	  and the '-u' option is used to reference a single URL. Please see the man page for details.
	---
	* User Configuration Area Changes:
	  The "User Configuration Area" at the top the script has been relocated to an external file. Config file path may be specified with the '-C' flag.
	  This change allows for users to easily switch between a command line or config file driven workflow. As such, unbound-adblock may now be used as a
	  versatile commandline utility with many potential use cases. If no config file is specified, then all configuration will be performed from the commandline.


- Correctness:
	* Use specific integer/boolean checks to avoid undefined behavior.
	* Implemented better regular expressions to validate domain names.
	* We now properly handle Windows line endings (carriage returns).
	* Make sure ZSH doesn't clear the 'set -efo pipefail' options.


- Misc:
	* Add support for whitelisting URL's with the unbound local-data backend.
	* Add support for 'ugrep' - a fast, portable, multithreaded grep replacement written in modern C++.
	* Add support for "goawk", a POSIX compliant awk implementation written in Go.