alpha: reverting alpha value back to float and casting to double instead ref. #13

Merge pull request #12 from veltza/fix-controlclear

Prevent the control clear patch from blocking ctrl-u

Prevent the control clear patch from blocking ctrl-u

The control clear patch is not compatible with the latest ctrl-u feature
because it blocks all ctrl shortcuts. This fix ensures that the patch is
active only when the ctrl key is pressed without any other keys.

Note that the patch is also active when the shift or alt key is pressed
without any other keys. This is an undocumented feature of this patch
and is caused by the iscntrl function, which returns true if the ascii
value is zero.

Support ^U for clearing password

^U is a fairly common key combo for clearing fields, this patch adds
support for it.

https://git.suckless.org/slock/commit/bf0a5577acbd9ec7c6a577601b97144b205840d7.html
https://git.suckless.org/slock/commit/3791a996e230aec59d61faea46634ae4f031e359.html

quick cancel: allow cancelling by key press in addition to mouse movement ref. #11

simplify post-lock cmd and die if it fails

this patch does two things:

0. simplify the code by using posix_spawn()
1. unify the behavior of what happens if the post-lock cmd fails.

currently, if `fork()` fails, slock will die without locking the screen.
HOWEVER if `execvp()` fails it prints a message to stderr (which the
user cannot see since the screen has been locked already) and only exits
the child while the parent locks the screen.

to reproduce:

	# slock some_bin_that_doesnt_exist

this behavior is inconsistent, if the idea is that post-lock cmd is
_not_ important then we shouldn't `die()` on `fork()` failure either.
and if we assume that the post-lock cmd _is_ important, then we should
die on exec failure as well.

this patch assumes the latter and calls `die()` if `posix_spawn()`
fails.

ref.
https://git.suckless.org/slock/commit/a70d5d2429abf8dcb70a8817990975dc9a621d27.html

write version to stdout like the man page says

ref.
https://git.suckless.org/slock/commit/e8bca65d629a4faa89439c9f0e599efb5a259573.html

Merge pull request #8 from herrwusel/pam_consistant

Consistent unlock styles with pam and blur patches

Consistent unlock styles with pam and blur patches

Adding background image patch

Proposed change to avoid high CPU usage ref. #7

Fix for secret password patch compilation error ref. #6

Adding dwmlogo patch ref. #5

Adding auto-timeout patch

Adding secret password patch

Adding failure-command patch

Adding color message patch ref. #3

Adding alpha patch

Adding blur pixelated screen patch

Adding keypress_feedback patch