For this client program, it's hard to imagine a case where
autostarting a jack server is reasonable just to query or set the bufsize.

This is in accordance with programs like jack_lsp, jack_connect
(do not start a server if none is running).

- Use jack_set_error_function() (currently no-op)

In the case of clients that use jack_options_t JackNoStartServer,
running it with no server started produces verbose output in the form:

```
Cannot connect to server socket err = No such file or directory
Cannot connect to server request channel
jack server is not running or cannot be started
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
JackShmReadWritePtr::~JackShmReadWritePtr - Init not done for -1, skipping unlock
JACK server not running?
```

Setting a no-op error handler before trying jack_client_open()
will hide these messages.

Checking the status allows to output a user-friendly error message.

The first string is generic for any fail of jack_client_open()

`Error: cannot connect to JACK, `
Most importantly it informs the user that there is an error.

Depending on status the string is extended with either
`server is not running.`
or
`jack_client_open() failed, status =...`
if the status indicates anything else than JackServerFailed.

Running jack_lsp or jack_connect with no server running outputs (new)
`
Error: cannot connect to JACK, server is not running.
`

More aspects of example_clients/* can be reviewed for unification.
Some do ask:
`JACK server not running?`
Others tell
`JACK server not running.`

If this commit won't show deficits: jack_client_open() sections can be
changed in all example_clients accordingly.

Note: obviously the --version option is currently a NO-OP in many client programs. This needs a closer look.

Only REG_EXTENDED regular expressions are understood.

Eg. foo_{1|2} is NOT understood.

This commit solves segfault when using invalid regular expressions.
See https://github.com/jackaudio/jack2/issues/433

Running ldd -r -u <jack_binary> should tell about unused dependencies.

Also see
https://github.com/jackaudio/jack2/issues/430

Minor changes
-set script to fail on any error
-check early for existing jackd
-add comments

* Revert "oss_driver: Use float to S32 conversion if requested"

This reverts commit c5a0f5ea1c.

* Revert "alsa_in/out: Use float to S32 conversion if requested"

This reverts commit 148c8d8e6a.

* Revert "alsa_driver: Use float to S32 conversion if requested"

This reverts commit d017e1fffe.

* Revert "memops: Provide function for float to S32 conversion"

This reverts commit bb99e09b99.

* Revert "memops: Align S24LE and S32LE to float conversion"

This reverts commit b4ea23df6a.

* Revert "memops: Provide function for S32 to float conversion"

This reverts commit 244fc27e29.

* Revert "memops: Align float to S24LE and S32LE conversion"

This reverts commit 4455fe020c.

* Revert "memops: Remove not used conversion macros"

This reverts commit a82f3f2fb4.

* Revert "memops: Use right-aligned S24LE to float conversion"

This reverts commit e753254313.

* Revert "memops: Use right-aligned float to S24LE conversion"

This reverts commit 831163e516.

Running script 'jack_property_test.sh' with recent jack1 and jack2 git builds show different results.
Notes:
	-jack1 gives only false positives due to a small text change
	-jack2 has issues using client name as subject/identifier/uuid
		-> see '**      FAILED' lines
	-jack1 is much faster in performing the same script
	-running the script in a loop causes memory problems with jack2

output running with jack1:

test system_c1: jack_property -D
	OK: 0
**	FAILED: JACK metadata successfully delete
**	EXP EQ: JACK metadata successfully deleted
test system_c2: jack_property -l
	OK: 0
	OK:
test system_c3: jack_property -c -l system
	OK: 0
	OK:
test system_c4: jack_property -c -s system client_key client_value
	OK: 0
	OK:
test system_c5: jack_property -c -l system
	OK: 0
	OK: key: client_key value: client_value
test system_c6: jack_property -c -l system client_key
	OK: 0
	OK: client_value
test system_c7: jack_property -l
	OK: 0
	OK: key: client_key value: client_value
test system_c8: jack_property -p -l system:non
	OK: 0
	OK: cannot find port name system:non
test system_p1: jack_property -D
	OK: 0
**	FAILED: JACK metadata successfully delete
**	EXP EQ: JACK metadata successfully deleted
test system_p2: jack_property -l
	OK: 0
	OK:
test system_p3: jack_property -p -l system:playback_1
	OK: 0
	OK:
test system_p4: jack_property -p -s system:playback_1 port_key port_value
	OK: 0
	OK:
test system_p5: jack_property -p -l system:playback_1
	OK: 0
	OK: key: port_key value: port_value
test system_p6: jack_property -p -l system:playback_1 port_key
	OK: 0
	OK: port_value
test system_p7: jack_property -p -d system:playback_1 port_key
	OK: 0
	OK:
test system_p8: jack_property -p -l system:playback_1 port_key
	OK: 0
	OK: Value not found for port_key of system:playback_1
test system_p9: jack_property -p -d system:playback_1 port_key
	OK: 0
	OK: "port_key" property not removed for system:playback_1
test system_p10: jack_property -p -l system:playback_1
	OK: 0
	OK:
test system_p11: jack_property -p -l system:playback_1 non
	OK: 0
	OK: Value not found for non of system:playback_1
test system_p12: jack_property -c -l non
	OK: 0
	OK: cannot get UUID for client named non
metro:120_bpm
test metro_c1: jack_property -D
	OK: 0
**	FAILED: JACK metadata successfully delete
**	EXP EQ: JACK metadata successfully deleted
test metro_c2: jack_property -l
	OK: 0
	OK:
test metro_c3: jack_property -c -l metro
	OK: 0
	OK:
test metro_c4: jack_property -c -s metro client_key client_value
	OK: 0
	OK:
test metro_c5: jack_property -c -l metro
	OK: 0
	OK: key: client_key value: client_value
test metro_c6: jack_property -c -l metro client_key
	OK: 0
	OK: client_value
test metro_c7: jack_property -l
	OK: 0
	OK: key: client_key value: client_value
test metro_c8: jack_property -p -l metro:non
	OK: 0
	OK: cannot find port name metro:non
test metro_p1: jack_property -D
	OK: 0
**	FAILED: JACK metadata successfully delete
**	EXP EQ: JACK metadata successfully deleted
test metro_p2: jack_property -l
	OK: 0
	OK:
test metro_p3: jack_property -p -l metro:120_bpm
	OK: 0
	OK:
test metro_p4: jack_property -p -s metro:120_bpm port_key port_value
	OK: 0
	OK:
test metro_p5: jack_property -p -l metro:120_bpm
	OK: 0
	OK: key: port_key value: port_value
test metro_p6: jack_property -p -l metro:120_bpm port_key
	OK: 0
	OK: port_value
test metro_p7: jack_property -p -d metro:120_bpm port_key
	OK: 0
	OK:
test metro_p8: jack_property -p -l metro:120_bpm port_key
	OK: 0
	OK: Value not found for port_key of metro:120_bpm
test metro_p9: jack_property -p -d metro:120_bpm port_key
	OK: 0
	OK: "port_key" property not removed for metro:120_bpm
test metro_p10: jack_property -p -l metro:120_bpm
	OK: 0
	OK:
test metro_p11: jack_property -p -l metro:120_bpm non
	OK: 0
	OK: Value not found for non of metro:120_bpm
test metro_p12: jack_property -c -l non
	OK: 0
	OK: cannot get UUID for client named non
JACK metadata successfully delete
./jack_property_test.sh: line 215: 21025 Hangup                  jack_metro -b120
done, exit status is 1

real	0m1.011s
user	0m0.125s
sys	0m0.324s

==========================================
output running with jack2:

test system_c1: jack_property -D
	OK: 0
	OK: JACK metadata successfully deleted
test system_c2: jack_property -l
	OK: 0
	OK:
test system_c3: jack_property -c -l system
	OK: 0
	OK:
test system_c4: jack_property -c -s system client_key client_value
	OK: 0
	OK:
test system_c5: jack_property -c -l system
	OK: 0
	OK: key: client_key value: client_value
test system_c6: jack_property -c -l system client_key
	OK: 0
	OK: client_value
test system_c7: jack_property -l
	OK: 0
	OK: key: client_key value: client_value
test system_c8: jack_property -p -l system:non
	OK: 0
	OK: cannot find port name system:non
test system_p1: jack_property -D
	OK: 0
	OK: JACK metadata successfully deleted
test system_p2: jack_property -l
	OK: 0
	OK:
test system_p3: jack_property -p -l system:playback_1
	OK: 0
	OK:
test system_p4: jack_property -p -s system:playback_1 port_key port_value
	OK: 0
	OK:
test system_p5: jack_property -p -l system:playback_1
	OK: 0
	OK: key: port_key value: port_value
test system_p6: jack_property -p -l system:playback_1 port_key
	OK: 0
	OK: port_value
test system_p7: jack_property -p -d system:playback_1 port_key
	OK: 0
	OK:
test system_p8: jack_property -p -l system:playback_1 port_key
	OK: 0
	OK: Value not found for port_key of system:playback_1
test system_p9: jack_property -p -d system:playback_1 port_key
	OK: 0
	OK: "port_key" property not removed for system:playback_1
test system_p10: jack_property -p -l system:playback_1
	OK: 0
	OK:
test system_p11: jack_property -p -l system:playback_1 non
	OK: 0
	OK: Value not found for non of system:playback_1
test system_p12: jack_property -c -l non
	OK: 0
	OK: cannot get UUID for client named non
metro:120_bpm
test metro_c1: jack_property -D
	OK: 0
	OK: JACK metadata successfully deleted
test metro_c2: jack_property -l
	OK: 0
	OK:
test metro_c3: jack_property -c -l metro
**	FAILED: 255
**	EXP EQ: 0
**	FAILED: cannot parse client UUID as UUID
**	EXP EQ:
test metro_c4: jack_property -c -s metro client_key client_value
**	FAILED: 255
**	EXP EQ: 0
**	FAILED: cannot parse client UUID as UUID
**	EXP EQ:
test metro_c5: jack_property -c -l metro
**	FAILED: 255
**	EXP EQ: 0
**	FAILED: cannot parse client UUID as UUID
**	EXP EQ: key: client_key value: client_value
test metro_c6: jack_property -c -l metro client_key
**	FAILED: 255
**	EXP EQ: 0
**	FAILED: cannot parse client UUID as UUID
**	EXP EQ: client_value
test metro_c7: jack_property -l
	OK: 0
**	FAILED:
**	EXP EQ: key: client_key value: client_value
test metro_c8: jack_property -p -l metro:non
	OK: 0
	OK: cannot find port name metro:non
test metro_p1: jack_property -D
	OK: 0
	OK: JACK metadata successfully deleted
test metro_p2: jack_property -l
	OK: 0
	OK:
test metro_p3: jack_property -p -l metro:120_bpm
	OK: 0
	OK:
test metro_p4: jack_property -p -s metro:120_bpm port_key port_value
	OK: 0
	OK:
test metro_p5: jack_property -p -l metro:120_bpm
	OK: 0
	OK: key: port_key value: port_value
test metro_p6: jack_property -p -l metro:120_bpm port_key
	OK: 0
	OK: port_value
test metro_p7: jack_property -p -d metro:120_bpm port_key
	OK: 0
	OK:
test metro_p8: jack_property -p -l metro:120_bpm port_key
	OK: 0
	OK: Value not found for port_key of metro:120_bpm
test metro_p9: jack_property -p -d metro:120_bpm port_key
	OK: 0
	OK: "port_key" property not removed for metro:120_bpm
test metro_p10: jack_property -p -l metro:120_bpm
	OK: 0
	OK:
test metro_p11: jack_property -p -l metro:120_bpm non
	OK: 0
	OK: Value not found for non of metro:120_bpm
test metro_p12: jack_property -c -l non
	OK: 0
	OK: cannot get UUID for client named non
JACK metadata successfully deleted
signal received, exiting ...
done, exit status is 1

real	0m2.806s
user	0m0.176s
sys	0m0.374s

Problem:

#set two properties for UUID 4294967296

$ jack_property -s 4294967296 "a" 1
$ jack_property -s 4294967296 b "2"

#-l lists them

$ jack_property -l
4294967296
key: b value: 2
key: a value: 1

#-l for UUID doesn't list them  <<<<<<

$ jack_property -l 4294967296
$ jack_property -l 4294967296 a
Value not found for a of 4294967296
$ jack_property -l 4294967296 b
Value not found for b of 4294967296

#it seems that 3 chars is the minimum length for value when querying for UUID

$ jack_property -s 4294967296 a 123
$ jack_property -l 4294967296
key: a value: 123
$ jack_property -l 4294967296 a
123

In example-clients/property.c:

/* list all properties for a given UUID */

                        if ((cnt = jack_get_properties (uuid, &description)) < 0) {
                                fprintf (stderr, "could not retrieve properties for %s\n", subject);
                                exit (1);
                        }

cnt is always 0 for values < 3 chars. Why?

In common/JackMetadata.cpp:

int JackMetadata::GetProperty(jack_uuid_t subject, const char* key, char** value, char** type)
int JackMetadata::GetProperties(jack_uuid_t subject, jack_description_t* desc)

This loop gets results:
while ((ret = cursor->get (cursor, &key, &data, DB_NEXT)) == 0) {

but are dropped because of this check:

/* result must have at least 2 chars plus 2 nulls to be valid
if (data.size < 4) {

This rule isn't understood. Explanations are welcome!
Reducing the check to 2 (1 char + null) will consider single char values.
This makes listing properties for a given UUID the same keys as when listing all UUIDs and keys.
No side-effects of lowering the value has been detected (yet).

Note: there is no problem getting "short" values in this method:
int JackMetadata::GetAllProperties(jack_description_t** descriptions)
(as used by jack_property -l without UUID)

jack_property output after change to (data.size < 2):

$ jack_property -s 4294967296 "a" 1
$ jack_property -s 4294967296 b "2"
$ jack_property -l
4294967296
key: b value: 2
key: a value: 1
$ jack_property -l 4294967296
key: b value: 2
key: a value: 1
$ jack_property -l 4294967296 a
1
$ jack_property -l 4294967296 b
2

Note: This change should be considered also for JACK1 (libjack/metadata.c)
to keep implementations in sync.

For OSX travis builds:
Since recently, brew install --c++11 stops the build.
Error: invalid option: --c++11
The command "./.ci/install-deps.sh" failed and exited with 1 during .
Your build has been stopped.

See https://github.com/jackaudio/jack2/issues/413

Notes:
The name length test still fails.

jack_client_open() will only allow 63 printable chars (unlike expected 64 == JACK_CLIENT_NAME_SIZE).
This difference isn't explained by the terminating NULL character. jack_client_name_size() takes care of that (returns JACK_CLIENT_NAME_SIZE + 1).
char arrays are initialized like arr[JACK_CLIENT_NAME_SIZE + 1] in many files und truncated like arr[JACK_CLIENT_NAME_SIZE].

Probable reason for 63: ':' is part of the client name and implicitely added later.
Name used by caller does not include ':' thus jack_client_open() will allow only JACK_CLIENT_NAME_SIZE - 1 printable chars.

This line in common/JackConstants.h gives a hint that ':' might be counted in for JACK_CLIENT_NAME_SIZE
#define REAL_JACK_PORT_NAME_SIZE JACK_CLIENT_NAME_SIZE + JACK_PORT_NAME_SIZE // full name like "client_name:short_port_name"

Currently many char arguments are described like
@param client_name of at most jack_client_name_size() characters

This can be confusing in two ways:
-jack_client_name_size() does include the NULL so it's one less 'payload' character
-if the returned size is used exactly as described for function jack_client_name_size() including NULL,
it won't work with jack_client_open() or jack_port_register() etc. because of another reduction (eventually for the ":").

!! This needs to be verified and documentation needs to be reviewed. !!

Note: the client name length test still fails, this is a different issue.

The newly added persons have contributed code to JACK in the past.
(mentioned in at least one file header)

tests/cpu.c:    Copyright (C) 2005 Samuel TRACOL
linux/alsa/usx2y.c:    Copyright (C) 2005 Karsten Wiese, Rui Nuno Capela
linux/alsa/ice1712.h:    Copyright (C) 2000 by Jaroslav Kysela <perex@suse.cz>
example-clients/metro.c:    Copyright (C) 2002 Anthony Van Groningen
dbus/controller_iface_transport.c:    Copyright (C) 2008 Juuso Alasuutari
common/netjack.h:    Copyright (C) 2003 Robert Ham <rah@bash.sh>
common/jack/ringbuffer.h:  Copyright (C) 2003 Rohan Drape
common/jack/metadata.h:  Copyright (C) 2011 David Robillard
common/JackMidiPort.cpp:Original JACK MIDI implementation Copyright (C) 2004 Ian Esten
linux/firewire/JackFFADODriver.cpp:Copyright (C) 2012 Jonathan Woithe
common/jack/statistics.h:  Copyright (C) 2004 Rui Nuno Capela, Lee Revell

The authors list should be up-to-date now.

-Add "new" alumni authors according to jackd manpage listed under "Programming"

+Andy Wingo
+Jack O'Quin
+Jeremy Hall
+Johnny Petrantoni
+Jussi Laako
+Kai Vehmanen
+Melanie Thielker
+Steve Harris
+Taybin Rutkin
+Tilman Linneweh
+Stefan Schwandter
+Alexandre Prokoudine

-Add new authors according to https://github.com/jackaudio/jack2/graphs/contributors
-Order alphabetically by FIRST NAME (this is simple for |sort)

Karl Lindén (karllinden)
Timo Wischer (twischer-adit)
Thomas Brand (7890)
Cédric Schieli (sdrik)
Markus Seeber (mseeber)
Alba Mendez (jmendeth)
David Runge (dvzrv)
Olivier Humbert (trebmuh)
Yasuhiro Fujii (y-fujii)
Gaël Portay (gportay)
James P. Thomas (jamespthomas)
Andreas Müller (schnitzeltony)
Holger Dehnhardt (dehnhardt)
Rui Nuno Capela (rncbc)
Michał Szymański (smiszym)
Francis Pinteric (fjapinteric)
Bruno Vernay (BrunoVernay)
Hunter L. Allen (allenh1)
Edward Betts (EdwardBetts)
Thomas Petazzoni (tpetazzoni)
James Cowgill (jcowgill)
Samuel Martin (tSed)
Bernhard M. Wiedemann (bmwiedemann)
Jacek Konieczny (Jajcus)
Andrew Kelley (andrewrk)
Maks Naumov (maksqwe)
Julien Acroute (Vampouille)
Youri Westerman (4c0n)
Olaf Hering (olafhering)
Ricardo Crudo (ricardocrudo)
Maxim Grishin (Igevorse)
Valentin David (valentindavid)
Joshua Moyerman (jmoyerman)
Arnaud Rebillout (elboulangero)
Alexander Graf (agraf)
Eliot Blennerhassett (eliotb)
Deven Lahoti (dlahoti)

Not added (need more info) github handles
fps
mojofunk
e9925248
farwayer
l1n
stratakis
m-grabner
bkuhls
escitalopram

The FreeBoB project was renamed to FFADO in 2007.
All users should use the FFADO backend by now (2019).

Backend name to be removed: "freebob"
Alternative backend to use: "firewire"

Please check the jackd manpage for details about "firewire" backend.

This commit is part of legacy cleanup.

closes issue #365.