Commit Graph

1541 Commits

Author SHA1 Message Date
sonninnos
610207dcfd
Menu sounds fixes (#15384) 2023-06-15 21:36:20 +02:00
libretroadmin
e9387193d5 Some style nits 2023-06-15 14:05:06 +02:00
libretroadmin
723f54b713 (common wasapi) Small cleanups, always have a last return value 2023-06-15 14:02:14 +02:00
libretroadmin
ab7d4e1aec Need to add retro_common_api.h to this header file if you're going to
use RETRO_BEGIN_DECLS/RETRO_END_DECLS
2023-06-15 13:56:57 +02:00
libretroadmin
246cceeb27 Silence more signedness warnings 2023-06-14 19:51:31 +02:00
sonninnos
c8b6f7fcd5
(WASAPI) Don't reset OS mixer volume in shared mode (#15369) 2023-06-13 07:52:52 +02:00
Jesse Talavera-Greenberg
938d60d0f4
Add microphone support via a new driver (#14731)
* Some slight fixes

* Update libretro.h

* Log calls to RETRO_ENVIRONMENT_GET_MICROPHONE_INTERFACE

* Finish proof-of-concept for mic support

- It works, but doesn't support floating-point audio yet
- It may need to be resampled, too

* Add macros that aren't available in SDL 2

* Comment out a variable definition for now

- For C89 compliance

* Add some comments for clarity

* Let ALSA tolerate a null new_rate

* Partial ALSA microphone support

- Not yet tested
- Mic is created and destroyed
- Mic can also be paused or unpaused
- Mic is paused or unpaused with the rest of the driver
- Microphone is not yet read

* Install error logging in the ALSA driver

- It defers to RARCH_ERR

* Free the ALSA microphone in alsa_free

* Fix an indent

* First draft of alsa_read_microphone

* Deinitialize SDL Audio in sdl_audio_free

* Save and restore the ALSA error logger

- You should always practice safe global state

* Add newlines to some RARCH_ERRs

* Add some logging

* Check for the mic being active via settings instead of via flags

* Adjusted a log entry to be less misleading

- A frequency of 0Hz looks weird to the uninformed
- In reality, it means the driver used the requested frequency

* Fix an incorrect format string

* Tidy up logging in alsa.c

* Rename audio_enable_microphone to audio_enable_input

* Rename microphone_device to audio_input_device

* Add audio_input_latency and audio_input_block_frames settings

* Add all mic-related settings to the options menu

* Adjust logging for alsa.c

- Log the ALSA library version
- Add errno details

* Refer to the microphone in logs by name

* Use %u instead of %d for some log items

* Add input_samples_buf

* Remove an inaccurate comment

* Change type of input_samples_buf

* Clean up audio_driver_flush_microphone_input

* Comment convert_float_to_s16

- It helped me understand what it's doing
- Turns out it'll work just fine on mono audio

* Don't use the resampler for mic input

* Fix crash in the ALSA driver when reading from a mic

* Update some logging messages

* ALSA support now works for mics

* Reuse some common functions in alsa.c

* Add alsa_thread_microphone_t

* Refactor alsa.c

- Introduce alsa_init_pcm to init any PCM that we're using
- Vastly simplifies the implementation of alsa_init and alsa_init_microphone
- Will be used for the read-based versions next

* Make ALSA logging a little more consistent

* Clean up the mic with alsa_free_microphone if alsa_init_microphone fails

* Remove an unused function

* Move some cleanup in alsa.c to a common function

* First crack at mic support for alsathread

- Refactor some duplicate code into functions
- Use functions introduced in alsa.c
- Create and destroy the mic

* Slight cleanups for clarity

* Implement alsa_thread_set/get_microphone_state

* More work on alsathread

- No more crashing, but the mic just returns silence

* Slight cleanups for clarity

* Add alsa_set_mic_enabled_internal

- For setting the state of a microphone while considering its current state

* Use alsa_set_mic_enabled_internal

* Log a little more info

* Log when the audio driver is started/stopped

* Move base microphone driver code into a new directory

- Add microphone_driver.c to Makefile.common
- Rename functions as needed

* Initialize and deinitialize the microphone driver

* Implement sdl_microphone.c

* Un-const an argument

- In case the driver context needs to do any locking

* Revise comments for microphone_driver.h

* Remove an unimplemented function

* Remove some functions from the mic driver

* Remove mic functions from audio_thread_wrapper

* Remove mic functions from sdl_audio

* Fix microphone_null

* Split the mic code for the alsa audio drivers into microphone drivers

* Fix an extra struct member

* Add a setting for the mic driver

* Add a command to reinitialize the microphone driver

* Rename mic-related settings

* Add DRIVER_MICROPHONE_MASK to DRIVERS_CMD_ALL

* Rename audio_enable_input to microphone_enable

* Remove some labels from qt_options

* Search for microphone_driver within find_driver_nonempty

* Clean up some mic driver code

* Pending mics now return silence

* Adjust some logging and comments

* Some cleanup in the microphone driver

* Invert a flag check

- Oops

* Fix a log message

* Fix the wrong flags being checked

* Slight refactor of wasapi_init_device

- Add a data_flow parameter
- Declare it in a header
- In preparation for WASAPI mic support

* Add some WASAPI macros for _IAudioCaptureClient

* Move some common WASAPI functions to audio/common/wasapi.c

- They'll be used by the mic and the audio drivers

* Add wasapi_log_hr

* Generalize mmdevice_list_new to look for capture devices, too

* Fix a function declaration

* Move driver-specific device_list_new functions into their respective files

* Clean up some declarations

* First draft of wasapi microphone driver

* Add wasapi_microphone_device_list_free

* Change function parameter names to be consistent with microphone_driver

* Partially implement wasapi_microphone_read

- Mostly copied from the audio driver so far
- It doesn't compile yet
- But it'll be beautiful when I'm done with it

* Refactor the mic driver's functions

- Rename get_mic_active to mic_alive
- Split set_mic_active into start_mic and stop_mic
- Refactor the SDL mic driver accordingly

* Edit some WASAPI functions for logging and clarity

* Implement more of the WASAPI mic driver

* Rename write_event to read_event

* Pass the WASAPI driver context to the various read functions

* Mostly implement the read function for the WASAPI mic driver

* Fix a crash in microphone_driver

- Forgot to move the position of the name of null_driver

* Reduce some logging in wasapi common functions

- Only log the chosen audio client format, not all attempted ones

* Add some macro wrappers for IAudioClient methods

* Update mic driver configuration

- Make the mic driver configurable in the menu
- Add config items for WASAPI-related options similar to the audio driver

* Fix a menu entry scrolling through audio devices instead of mic devices

* Add some utility functions

* Expose the new utility functions in wasapi.h

* Add extra logging in the WASAPI common functions

* Add sharemode_name

* Use _IAudioClient_Initialize macro in some places

* Pass channels to wasapi_init_client

- Remember, mics are in mono

* Use _IAudioClient_Initialize macro some more

* Forgot to pass channels in some places

* Add some utility functions

* Forgot an #include

* Add wasapi_select_device_format

* Simplify the format selection logic in wasapi_init_client_sh

* Unset the microphone in wasapi_microphone_close_mic

- Ought to prevent a potential segfault

* Simplify some logging

* Fix incorrect value being passed to _IAudioCaptureClient_ReleaseBuffer

* Remove some unneeded logging

* Add some values to hresult_name

* Polish up wasapi_select_device_format

- Test for formats manually when Windows can't
- Add some debug logging
- Check for channels

* Compute the fields of WAVEFORMATEXTENSIBLE correctly

- As per the doc's stated requirements

* Simplify logic for WASAPI client creation

* Fix a potential hang in wasapi_microphone_read_shared_buffered

* Stop the microphone if the driver is stopped

* Don't name the microphone event

* Ensure that wasapi_init_client reports the correct format and rate

* Implement exclusive microphone read access for WASAPI

* Add _IAudioCaptureClient_GetNextPacketSize macro

* Organize cases in hresult_name

* Clear some extra fields if wasapi_set_format is setting a Pcm format

* Adjust some logs

* Adjust some logs

* Remove unneeded local vars

* Add a log

* Update wasapi.c

* Update wasapi.c

* Fix shared-mode mic support in WASAPI producing broken input

- Turns out it had nothing to do with shared mode

* Reuse a common function

- Remove wasapi_microphone_read_shared_buffered
- Rename wasapi_microphone_read_exclusive to wasapi_microphone_read_buffered

* Remove some code I was using for test purposes

* Clarify some language

* Double the default shared-mode mic buffer length

* Split getting a device's name into a separate function, then use it

* Fix the ALSA mic drivers

- To comply with changes I previously made to the mic driver interface

* Remove unused synchronization primitives from the SDL microphone driver

* Add sdl_microphone_mic_use_float

* Document audio_driver_state_flags

- I needed to understand these to see if similar flags were required for the mic driver

* Remove an unused function in wasapi.c

* Add and document flags in microphone_driver.h

* Remove driver-specific mic start/stop functions

- The mic driver itself doesn't do much processing
- That honor goes to individual mics

* Remove some unused fields in microphone_driver.h

* Add CMD_EVENT_MICROPHONE_STOP/START

* Remove unused functions from microphone_null

* Change how the mic driver state is referenced in some places

* Simplify the SDL microphone driver

- The driver backend no longer keeps a reference to the mic (the frontend does that)
- Remove functions that are no longer needed
- Don't track paused state, just query the mic itself

* Simplify the WASAPI microphone driver

- Don't track the driver running state or the microphone handle, the frontend does that now
- Remove support for unbuffered input (hunterk suggested that it wasn't necessary)

* Make microphone_wasapi_sh_buffer_length a uint, not an int

- It won't be negative anymore
- 0 now represents the default value

* Make the microphone frontend more robust

- Improve documentation for how various functions should be implemented
- Closes all microphones before freeing the driver (so backends don't have to)
- Tracks the enabled state of each microphone, so backends don't have to (but they still can)

* Stop the mic driver in core_unload_game

* Ensure mic support is compatible with the revised menu code

* Move alsa.h into audio/common

* Remove RETRO_ENVIRONMENT_GET_MICROPHONE_ENABLED

- It was never really needed

* Refactor the ALSA microphone driver

- Move common ALSA functions to audio/common/alsa.c
- Replace alsa_set_mic_enabled_internal with alsa_start/stop_pcm
- Don't track the microphone handle in the ALSA driver context
- Remove unneeded fields

* Move some common alsathread code into audio/common/alsathread.c

* Change return type of mic_driver_open_mic_internal to bool

* First crack at resampling mic input

* Remove an extraneous check

- I think something distracted me when I was writing this line

* Add stereo/mono conversion functions

* Make alsa_start_pcm and alsa_stop_pcm more robust

- They now return success if the stream is already running and stopped, respectively

* Revise some mic-related comments in libretro.h

* First crack at resampling mic input

* Simplify an expression

* Simplify an expression

* Fix a log tag

* Allow mic resampler to be configured separately from audio resampler

* Add some comments

* Set the source ratio to something sensible

* Stop deadlock in `alsathread` mic driver

* Allow mics to be initialized even when core is loaded from CLI

- When loading content from CLI, the drivers are initialized a little differently
- That threw off the mic initialization code

* Rename the functions in retro_microphone_interface

* Revise some mic-related comments in libretro.h

* Update retro_microphone_interface

- Add get_mic_rate
- Add a parameter to open_mic
- The modifications don't do anything yet

* Use parameter objects in the microphone handle

* Replace get_mic_rate with get_params

* Add a microphone interface version

* Remove part of a comment

* Set the effective params in mic_driver_microphone_handle_init

* Drop a stray newline

* Change where the mic interface is zeroed

- I was accidentally throwing out the version that the core was asking for

* Reduce logspam for wasapi_set_nonblock_state

- Now it only logs when the sync mode is changed

* Change DEFAULT_WASAPI_SH_BUFFER_LENGTH to 0

- -16 is no longer a valid value

* Set the new_rate in wasapi_init

* Change description of microphone sample rate in the settings

* First attempt at resampling configured mic input

* Forgot a section

* Fix some input samples being skipped

* Rename a variable for clarity

* Add microphone.outgoing_samples

* Update the mic driver

- Processed samples are now buffered
- The resampler is skipped if the ratio is (very close to) 1

* Remove part of a comment

* Update some comments in audio_resampler.h

* Slightly refactor the SDL microphone driver

- Move SDL_AudioSpec to a field of sdl_microphone_handle_t
- Allow SDL to change the requested format and sample rate
- Request floating-point input
- Implement sdl_microphone_mic_use_float

* Fix a non-C89-compliant declaration

* Add new files to griffin.c

* Remove a C++-style comment

* Add two more files to griffin.c

* Remove some unneeded declarations in microphone_driver.h

* Remove a stray comma in configuration.c

- For C89 compliance

* Fix compilation on some platforms

* Change some function signatures

* Make the ALSA drivers always set the audio rate

* Fix the alsathread mic driver

* Make state_manager_frame_is_reversed return false if HAVE_REWIND isn't defined

* Mute the microphone if the core is running in fast-forward, slow-mo, or rewind

* Clarify a comment

* Clarify a comment

* Add a comment

* Don't allocate memory for slowmo samples in the mic driver

- We're not supporting slowmo for mics, so it's not needed

* Fix a {

* Add my name to AUTHORS.h

* Add driver_lifetime_flags

- For drivers that have special setup/teardown needs

* Ensure that resetting the mic driver maintains active mic handles

- Prevents fullscreen toggle from stopping all mic input

* Update CHANGES.md

* Move some default microphone settings to a new part of the config file

* Ensure that RetroArch can use the audio format that Windows suggests

* Remove references to mic support in the SDL audio driver

* Remove unused WASAPI functions

* Return failure if RetroArch couldn't select a WASAPI format

* Ensure that Windows uses the WASAPI mic driver by default

* Treat disabled mic support as a warning, not an error

* Clarify some WASAPI-related microphone settings

* Remove some unused variables

* Add or revise microphone-related comments

* Rearrange doc comments for microphone types in libretro.h

* Remove a space

* Remove some unused flags

* Remove ALSA error logger

- It was never used anyway

* Remove unneeded microphone-related arguments

* Document a parameter

* Remove a logging call

* Add a constant for the microphone's shared buffer length for WASAPI

* Fix stylistic inconsistencies

* Make mic_driver_get_sample_size a macro instead of a function

* Move the microphone implementation to the audio directory

* Make microphone support optional (but enabled by default)

* Fix the griffin build
2023-06-06 21:55:06 +02:00
libretroadmin
8a5a59da50 Refactors, move some functions to retroarch.c and make them static 2023-05-31 16:08:31 +02:00
libretroadmin
c0ba738f0d Header uniformity - enums on top, then structs, then public declarations 2023-05-30 21:03:36 +02:00
Eric Warmenhoven
6506b65ce7 Fix #15316 - on iOS, stop/start audio on interruptions 2023-05-26 03:27:31 +02:00
Felipe Tavares
ea81928e39
Fast-Forward Audio Resampling (#15173)
* 🎵 Fast forward audio resampling. Solves #15160.

Previously, we avoided doing any resampling while fastforwarding based
on the assumption it was impossible to make the audio not crackle due to
both flush-to-flush timing fluctuations and timer accuracy.

However, turns out this is not the case. The audio doesn't "crackle" per
se when the timing fluctuates! It's just that the sounds don't make
sense since the time compression and decompression caused by the flush
time fluctuations mess with the audio consistency.

To work around that, we introduce a running average flush delta time
that makes sure the audio is both resampled to approximately the correct
rate and consistent.

This was tested in two settings:

- Limited rate fastforwarding (2x-4x)
- Unlimited fastforwarding

In both cases it seems to work well, but with unlimited fastforwarding
it's just high pitched and annoying, so this is probably the most useful
in the 2x to 4x range.

* Move declartion to support C89

* resampling ratio upper and lower bounds

* Add toggle for speeding up audio
2023-04-20 17:14:47 +02:00
sonninnos
e2a264700a
Audio output menu item reinit fix (#15190) 2023-04-14 07:18:21 +02:00
sonninnos
07c371533f
WASAPI Frame Delay fix + cleanups (#15187) 2023-04-13 20:20:47 +02:00
zoltanvb
4350ec24be
Support device list for PulseAudio (#15174)
As mentioned in https://github.com/libretro/RetroArch/issues/14954,
audio device selection works only if respective functions are
implemented in audio driver.

Added sink listing and selection. Common menu code takes care of the rest.
2023-04-09 18:15:48 +01:00
libretroadmin
dc6b6d5cdb (XAudio) Header cleanups 2023-03-13 04:23:25 +01:00
libretroadmin
88cd91c586 Cleanup some xaudio headers 2023-03-13 04:12:18 +01:00
libretroadmin
7ebab640d7 Cleanups/style nits 2023-02-23 13:15:14 +01:00
sonninnos
482c8ccf35
Add dropdown menu for audio device (#14914) 2023-01-28 02:22:08 +01:00
libretroadmin
daa9e352cc Remove asserts 2023-01-09 00:51:05 +01:00
Skirlez
8a127eff02 Better scrolling sound implementation, add new 'notice back' sound
The closing info box sound (NOTICE_BACK) plays if you have the regular notice sound on, implemented generally.

audio_driver_mixer_play_menu_sound(i) will now stop sound i before playing it, so when you for example, cancel in rapid succession, it will properly play all canceling sound effects instead of not doing anything if the sound is already playing.

This scrolling implementation is a lot more general than the first one, to the point where RGUI plays all the correct sounds without any special additions. However, the Ozone sidebar scrolling or category switching in XMB or MaterialUI are still handled inside their driver .c files.
This implementation also fixes an issue where if wraparound was disabled the sound would still play if you held on a direction. I've also fixed it manually for XMB category switching, since it's still handled there individually (turns out, Ozone sidebar and MaterialUI categories just don't respect the no wraparound option, so there's no need to implement a fix there as well)
2023-01-07 12:09:11 +01:00
libretroadmin
0c42e339e1 Silence some warnings that popup in Xcode 2023-01-04 18:42:35 +01:00
Skirlez
f84093496f implement scrolling sounds for ozone
using roughly the same implementation for the ok/notice/cancel sounds, but i've made an exclusive function for scrolling since it's going to be called a lot more than those sounds
2023-01-03 19:34:35 +01:00
zoltanvb
8bfa02e2ea
Fix for #14725 (#14750)
Revert one modification in 0f24d52407 that
makes "add to mixer" options do nothing.
2022-12-21 19:08:07 +01:00
libretroadmin
85598f24ad defines/ headers are libretro-common headers, search for them in
system header includes - other cleanups/nits
2022-12-15 15:09:40 +01:00
libretroadmin
5e6d917417 (audio/roar) remove errno.h include 2022-12-15 14:49:11 +01:00
Ruben Nine
db9d3d3507
Allow coreaudio3 driver to work with audio devices that have 2 or more output channels. (#14715) 2022-12-10 16:08:26 +01:00
sonninnos
3377fd55ab
Driver + hotkey list reorder (#14646)
* Reorder driver menu and lists

* Reorder hotkey list
2022-11-20 07:26:34 +01:00
LibretroAdmin
41de5ec80b Cleanups for runloop_state grabbing 2022-10-10 20:32:46 +02:00
LibretroAdmin
cc3a339011 (Runloop) Use more flags 2022-10-10 19:54:54 +02:00
LibretroAdmin
2371e5cbd2 (Runloop) Turn more bools into flags 2022-10-10 18:53:55 +02:00
LibretroAdmin
479e3b23d9 Turn content_get_status into content_get_flags 2022-10-09 20:32:39 +02:00
LibretroAdmin
d5a6c4f150 (content) use flags for content_state
(xaudio2) Use flags
2022-10-09 10:20:43 +02:00
LibretroAdmin
d506210fbe
(menu_driver.c) Use flags instead of bools (#14500)
* (menu_driver.c) Use flags instead of bools
2022-10-08 22:52:18 +02:00
LibretroAdmin
fcbd72dbf3
Use flags pt4 (#14497)
* * Use flags for rarch_state
* Get rid of ^M linebreaks in retroarch_types.h

* Buildfixes for consoles

* (audio driver) use flags instead of bools

* (video) Use flags instead of bools

* Rewrite input driver state bools into flags
2022-10-08 10:39:15 +02:00
LibretroAdmin
ace21d28f7 Fix C++ comments 2022-10-01 17:56:16 +02:00
LibretroAdmin
b2634ea588 * Create fill_pathname_join_special - and specify fill_pathname_join
as deprecated.
* Use fill_pathname_join_special in the vast majority of cases where
we can ensure out_path is a new empty string
* Get rid of some extension concatenation with strlcat where encountered
* Some general cleanups with NULL termination of strings that get immediately
passed to strlcpy/strlcpy-adjacent functions
2022-08-04 14:19:38 +02:00
libretroadmin
8ac1a36259 Don't do NULL termination on strings when passing to strlcpy and/or
a file_path function that calls strlcpy under the hood
2022-07-26 07:01:10 +02:00
LibretroAdmin
29774f5b7a
Small opts (#14186)
* (joypad_connection) Small optimizations -
* Turn functions static where possible
* Hose strlen call out of loop

* (input_driver.c) General cleanups:
* Some small code/style nits

task_screenshot.c:
* Move widget callback function for screenshots to task_screenshot.c

(file_path.c):
* Turn get_pathname_num_slashes into static function
* path_linked_list_free - always returns true, so get rid of return value
* path_linked_list_new - fix function signature
* path_get_archive_delim - do not NULL-terminate string, already done by strlcpy later on

General:
* Slight optimizations - use int/size_t for loop counter variable instead of unsigned
* Take advantage of fact that strlcpy already NULL-terminates, so don't do this explicitly
outside if we're just going to end up calling strlcpy/fill_pathname_join on it anyway
2022-07-19 10:01:33 +02:00
libretroadmin
adf9994828 Deprecate fill_pathname_base_noext 2022-07-11 20:13:44 +02:00
libretroadmin
0f24d52407 audio_driver_mixer_add_stream - add fall-through - simplify code 2022-07-09 13:44:55 +02:00
libretroadmin
f12ad9ed34 Simplify audio mixer functions 2022-07-05 18:57:56 +02:00
LibretroAdmin
4a38831c47
Try to reduce fixed size char arrays from PATH_MAX_LENGTH to lower sizes (#14062)
* Try to reduce fixed size char arrays from PATH_MAX_LENGTH to lower sizes
2022-06-18 19:07:15 +02:00
libretroadmin
a14ccc2d4d (Orbis) Remove some logs 2022-05-22 19:59:20 +02:00
OsirizX
c6d51fdb32 [ORBIS] Initial changes for PS4 2022-05-21 16:31:10 +02:00
jdgleaver
801b16885e Enable automatic configuration of 'VSync Swap Interval' 2022-05-12 14:22:46 +01:00
jSTE0
fccef557fc
miyoo: Enable ALSA audio driver and default to it (#13814)
Enable it as it does not freeze. This provides an audio backend that
can report its buffer status, allowing auto frame skip to work on cores
that support it.

Do not build or include alsathread as it results in choppy audio.
Similarly, leave tinyalsa disabled as it plays back at a higher pitch
and is also choppy.

Change the default sample rate to 32000Hz as the previous default of
32730Hz is derived from the 3DS.
2022-04-02 08:07:25 +01:00
twinaphex
4d112da58d Silence some MSVC code analysis warnings 2022-03-07 19:02:46 +01:00
Francisco Javier Trujillo Mata
86b47b4859
[PSP] Update Retroarch to latest PSPDev status (#13544)
* Added newlib changes

* Add action to launch PPSSPP simulator

* Remove legacy config for the stack and heap

* Add pthread

* Simplify kernel_functions and improve references to HAVE_KERNEL_PRX

* Add some flags

* Improve audio init/deinit

* Improve exit by clicking home

* Add CI for PSP1

* Update PSP.yml
2022-01-25 03:50:18 +01:00
Vladimir Serbinenko
4e24fb3d01
Add osx-ppc compilation for frontend (#13532)
* Fix old osx condition

Current code assumes that osx < 10.12 is equivalent to ppc osx. It's not
true as Leopard x86 is still < 10.12 but not ppc. As xcode compiles fat
binaries it includes osx x86 and compilation fails.

* Disable crtswitchres when no c++11 is available

Crtswitchres altually needs c++11. Since it's not that important to make
it compatible with lower c++, just disable if no c++11 is available

* Don't use firstObject on old Mac OS X.

It was introduced in 10.6, so on old ones just implement it ourselves

* Compile osx-ppc frontend

* osx-ppc: Build a fat binary

On 10.6 i386 xcode apparently refuses to build a pure ppc.
Settle for a fat binary.
2022-01-24 16:22:07 +01:00
Cthulhu-throwaway
690c802921
Netplay Stuff (#13375)
* Netplay Stuff

## PROTOCOL FALLBACK
In order to support older clients a protocol fallback system was introduced.
The host will no longer send its header automatically after a TCP connection is established, instead, it awaits for the client to send his before determining which protocol this connection is going to operate on.
Netplay has now two protocols, a low protocol and a high protocol; the low protocol is the minimum protocol it supports, while the high protocol is the highest protocol it can operate on.
To fully support older clients, a hack was necessary: sending the high protocol in the unused client's header salt field, while keeping the protocol field to the low protocol. Without this hack we would only be able to support older clients if a newer client was the host.
Any future system can make use of this system by checking connection->netplay_protocol, which is available for both the client and host.

## NETPLAY CHAT
Starting with protocol 6, netplay chat is available through the new NETPLAY_CMD_PLAYER_CHAT command.
Limitations of the command code, which causes a disconnection on unknown commands, makes this system not possible on protocol 5.
Protocol 5 connections can neither send nor receive chat, but other netplay operations are unaffected.
Clients send chat as a string to the server, and it's the server's sole responsability to relay chat messages.
As of now, sending chat uses RetroArch's input menu, while the display of on-screen chat uses a widget overlay and RetroArch's notifications as a fallback.
If a new overlay and/or input system is desired, no backwards compatibility changes need to be made.
Only clients in playing mode (as opposed to spectating mode) can send and receive chat.

## SETTINGS SHARING
Some settings are better used when both host and clients share the same configuration.
As of protocol 6, the following settings will be shared from host to clients (without altering a client's configuration file): input latency frames and allow pausing.

## NETPLAY TUNNEL/MITM
With the current MITM system being defunct (at least as of 1.9.X), a new system was in order to solve most if not all of the problems with the current system.
This new system uses a tunneling approach, which is similar to most VPN and tunneling services around.

Tunnel commands:
RATS[unique id] (RetroArch Tunnel Session) - 16 bytes -> When this command is sent with a zeroed unique id, the tunnel server interprets this as a netplay host wanting to create a new session, in this case, the same command is returned to the host, but now with its unique session id. When a client needs to connect to a host, this command is sent with the unique session id of the host, causing the tunnel server to send a RATL command to the host.
RATL[unique id] (RetroArch Tunnel Link) - 16 bytes -> The tunnel server sends this command to the host when a client wants to connect to the host. Once the host receives this command, it establishes a new connection to the tunnel server, sending this command together with the client's unique id through this new connection, causing the tunnel server to link this connection to the connection of the client.
RATP (RetroArch Tunnel Ping) - 4 bytes -> The tunnel server sends this command to verify that the host, whom the session belongs to, is still around. The host replies with the same command. A session is closed if the tunnel server can not verify that the host is alive.

Operations:
Host -> Instead of listening and accepting connections, it connects to the tunnel server, requests a new session and then monitor this connection for new linking requests. Once a request is received, it establishes a new connection to the tunnel server for linking with a client. The tunnel server's address and port are obtained by querying the lobby server. The host will publish its session id together with the rest of its info to the lobby server.
Client -> It connects to the tunnel server and then sends the session id of the host it wants to connect to. A host's session id is obtained from the json data sent by the lobby server.

Improvements (from current MITM system):
No longer a risk of TCP port exhaustion; we only use one port now at the tunnel server.
Very little cpu usage. About 95% net I/O bound now.
Future backwards compatible with any and all changes to netplay as it no longer runs any netplay logic at MITM servers.
No longer operates the host in client mode, which was a source of many of the current problems.
Cleaner and more maintainable system and code.

Notable functions:
netplay_mitm_query -> Grabs the tunnel's address and port from the lobby server.
init_tcp_socket -> Handles the creation and operation mode of the TCP socket based on whether it's host, host+MITM or client.
handle_mitm_connection -> Creates and completes linking connections and replies to ping commands (only 1 of each per call to not affect performance).

## MISC
Ping Limiter: If a client's estimated latency to the server is higher than this value, connection will be dropped just before finishing the netplay handshake.
Ping Counter: A ping counter (similar to the FPS one) can be shown in the bottom right corner of the screen, if you are connected to a host.
LAN Discovery: Refactored and moved to its own "Refresh Netplay LAN List" button.

## FIXES
Many minor fixes to the current netplay implementation are also included.

* Remove NETPLAY_TEST_BUILD
2021-12-19 16:58:01 +01:00