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-rw-r--r--pica-client/capturegain.cpp533
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diff --git a/pica-client/capturegain.cpp b/pica-client/capturegain.cpp
deleted file mode 100644
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--- a/pica-client/capturegain.cpp
+++ /dev/null
@@ -1,533 +0,0 @@
-/*
- (c) Copyright 2012 - 2026 Anton Sviridenko
- https://picapica.im
-
- This program is free software: you can redistribute it and/or modify
- it under the terms of the GNU General Public License as published by
- the Free Software Foundation, version 3.
-
- This program is distributed in the hope that it will be useful,
- but WITHOUT ANY WARRANTY; without even the implied warranty of
- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- GNU General Public License for more details.
-
- You should have received a copy of the GNU General Public License
- along with this program. If not, see <https://www.gnu.org/licenses/>.
-*/
-#include "capturegain.h"
-
-#include <QDebug>
-#include <QtGlobal>
-#include <QStringList>
-#include <cmath>
-
-#ifdef Q_OS_LINUX
-#include <alsa/asoundlib.h>
-#endif
-
-#ifdef HAVE_LIBPULSE
-#include <pulse/pulseaudio.h>
-#endif
-
-// Per platform factories, defined next to the implementations themselves -
-// same arrangement as NativeAudioBackend::create().
-#ifdef Q_OS_WIN
-CaptureGainControl *pica_create_wasapi_capture_gain(const QString &device);
-#endif
-
-#if defined(Q_OS_MACOS) || defined(Q_OS_MAC)
-CaptureGainControl *pica_create_coreaudio_capture_gain(const QString &device);
-#endif
-
-CaptureGainControl::~CaptureGainControl()
-{
-}
-
-static double clampGain(double v)
-{
- if (v < 0.0)
- return 0.0;
- if (v > 1.0)
- return 1.0;
- return v;
-}
-
-// PulseAudio is the one backend whose control goes past its nominal maximum -
-// PA_VOLUME_NORM is 100% and the server will happily sit above it. Clamping a
-// reading to 1.0 there would mean handing a user who had their source at 130%
-// back at 100% when the call ended, so that path keeps whatever it read and
-// only guards the bottom of the range and a runaway top.
-static double clampGainAmplified(double v)
-{
- if (v < 0.0)
- return 0.0;
- if (v > 2.5)
- return 2.5;
- return v;
-}
-
-#ifdef Q_OS_LINUX
-
-// The mixer lives on a card, but what we are handed is a PCM name. The two
-// namespaces overlap only by convention, so this covers the forms that
-// actually turn up in the device list and falls back to the default card for
-// anything else - which is right for plain "default" and no worse than
-// nothing for the exotic cases.
-static QString alsaCardFromPcm(const QString &pcm)
-{
- int card = pcm.indexOf(QLatin1String("CARD="));
- if (card >= 0)
- {
- QString name = pcm.mid(card + 5);
- int comma = name.indexOf(QLatin1Char(','));
- if (comma >= 0)
- name = name.left(comma);
- if (!name.isEmpty())
- return QStringLiteral("hw:") + name;
- }
-
- // "hw:1,0", "plughw:CARD=PCH,DEV=0", "dsnoop:1" - everything before the
- // first comma after the colon names the card.
- int colon = pcm.indexOf(QLatin1Char(':'));
- if (colon >= 0)
- {
- QString rest = pcm.mid(colon + 1);
- int comma = rest.indexOf(QLatin1Char(','));
- if (comma >= 0)
- rest = rest.left(comma);
- if (!rest.isEmpty())
- return QStringLiteral("hw:") + rest;
- }
-
- return QStringLiteral("default");
-}
-
-class AlsaCaptureGain : public CaptureGainControl
-{
-public:
- AlsaCaptureGain() : m_mixer(nullptr), m_elem(nullptr), m_min(0), m_max(0) {}
-
- ~AlsaCaptureGain() override
- {
- if (m_mixer)
- snd_mixer_close(m_mixer);
- }
-
- bool open(const QString &pcmName)
- {
- // The card the PCM name points at, and then the real cards as
- // fallbacks. "default" is not a card at all on a machine running a
- // sound server: attaching to it lands on the server's own software
- // volume, which is applied to samples the converter has already
- // digitised. That control cannot undo clipping - scaling a clipped
- // buffer down just gives a quieter clipped buffer - so calibrating
- // against it would turn the microphone down forever without the
- // clipping ever going away. Only a gain ahead of the ADC is any use
- // here, and tryCard() insists on one.
- QStringList candidates;
- candidates << alsaCardFromPcm(pcmName);
-
- if (candidates.first() == QLatin1String("default"))
- {
- for (int card = 0; card < 8; card++)
- candidates << (QStringLiteral("hw:") + QString::number(card));
- }
-
- for (int i = 0; i < candidates.size(); i++)
- {
- if (tryCard(candidates[i]))
- return true;
- }
-
- return false;
- }
-
- bool gain(double *out) override
- {
- if (!m_elem || !out)
- return false;
-
- // The kernel may have moved the control under us - another mixer app,
- // or the user's own volume keys.
- snd_mixer_handle_events(m_mixer);
-
- long v = 0;
- if (snd_mixer_selem_get_capture_volume(m_elem, SND_MIXER_SCHN_FRONT_LEFT, &v) < 0 &&
- snd_mixer_selem_get_capture_volume(m_elem, SND_MIXER_SCHN_MONO, &v) < 0)
- return false;
-
- *out = clampGain(double(v - m_min) / double(m_max - m_min));
- return true;
- }
-
- bool gainDb(double *out) override
- {
- if (!m_elem || !out)
- return false;
-
- snd_mixer_handle_events(m_mixer);
-
- // ALSA reports hundredths of a decibel. Not every element has a dB
- // mapping - the software controls a sound server exposes often do not.
- long v = 0;
- if (snd_mixer_selem_get_capture_dB(m_elem, SND_MIXER_SCHN_FRONT_LEFT, &v) < 0 &&
- snd_mixer_selem_get_capture_dB(m_elem, SND_MIXER_SCHN_MONO, &v) < 0)
- return false;
-
- *out = double(v) / 100.0;
- return true;
- }
-
- bool setGain(double value) override
- {
- if (!m_elem)
- return false;
-
- long v = m_min + (long)llround(clampGain(value) * double(m_max - m_min));
- return snd_mixer_selem_set_capture_volume_all(m_elem, v) >= 0;
- }
-
- QString description() const override { return m_name; }
-
-private:
- // A candidate has to have a decibel range as well as a volume range. That
- // is what separates a converter gain from a sound server's software fader:
- // the hardware control knows what its steps are worth in dB, the software
- // one only has a slider position. It is also what lets the caller bound
- // the total cut in dB, which is the only unit that means the same thing on
- // every backend.
- bool tryCard(const QString &card)
- {
- if (m_mixer)
- {
- snd_mixer_close(m_mixer);
- m_mixer = nullptr;
- m_elem = nullptr;
- }
-
- if (snd_mixer_open(&m_mixer, 0) < 0)
- {
- m_mixer = nullptr;
- return false;
- }
-
- const QByteArray cardUtf8 = card.toUtf8();
- if (snd_mixer_attach(m_mixer, cardUtf8.constData()) < 0 ||
- snd_mixer_selem_register(m_mixer, nullptr, nullptr) < 0 ||
- snd_mixer_load(m_mixer) < 0)
- return false;
-
- // "Capture" is what the recording gain is called on essentially every
- // card that has one; "Mic" turns up on the ones that do not separate
- // the input selector from the gain.
- m_elem = findNamed("Capture");
- if (!m_elem)
- m_elem = findNamed("Mic");
- if (!m_elem)
- m_elem = findNamed("Digital");
-
- if (!m_elem)
- return false;
-
- if (snd_mixer_selem_get_capture_volume_range(m_elem, &m_min, &m_max) < 0 || m_max <= m_min)
- return false;
-
- long dbMin = 0, dbMax = 0;
- if (snd_mixer_selem_get_capture_dB_range(m_elem, &dbMin, &dbMax) < 0 || dbMax <= dbMin)
- {
- m_elem = nullptr;
- return false;
- }
-
- m_name = QString::fromUtf8(snd_mixer_selem_get_name(m_elem)) +
- QStringLiteral(" on ") + card;
- return true;
- }
-
- snd_mixer_elem_t *findNamed(const char *want)
- {
- for (snd_mixer_elem_t *e = snd_mixer_first_elem(m_mixer); e; e = snd_mixer_elem_next(e))
- {
- if (!snd_mixer_selem_is_active(e) || !snd_mixer_selem_has_capture_volume(e))
- continue;
- if (qstrcmp(snd_mixer_selem_get_name(e), want) == 0)
- return e;
- }
- return nullptr;
- }
-
- snd_mixer_t *m_mixer;
- snd_mixer_elem_t *m_elem;
- long m_min;
- long m_max;
- QString m_name;
-};
-
-#endif // Q_OS_LINUX
-
-#ifdef HAVE_LIBPULSE
-
-// PulseAudio's introspection and its setters are both asynchronous, so this
-// keeps a connected context with a private mainloop and pumps it until each
-// operation has called back. Same shape as enumeratePulse() in
-// audiodevice.cpp, but long lived, since a call makes several of these.
-class PulseCaptureGain : public CaptureGainControl
-{
-public:
- PulseCaptureGain()
- : m_mainloop(nullptr), m_ctx(nullptr), m_channels(1),
- m_pending(false), m_ok(false), m_value(0.0), m_valueDb(0.0) {}
-
- ~PulseCaptureGain() override
- {
- if (m_ctx)
- {
- pa_context_disconnect(m_ctx);
- pa_context_unref(m_ctx);
- }
- if (m_mainloop)
- pa_mainloop_free(m_mainloop);
- }
-
- bool open(const QString &device)
- {
- m_mainloop = pa_mainloop_new();
- if (!m_mainloop)
- return false;
-
- m_ctx = pa_context_new(pa_mainloop_get_api(m_mainloop), "pica-client");
- if (!m_ctx)
- return false;
-
- if (pa_context_connect(m_ctx, nullptr, PA_CONTEXT_NOFLAGS, nullptr) < 0)
- return false;
-
- // Five seconds at 50ms a turn, so a server that never answers cannot
- // wedge the call setup.
- for (int i = 0; i < 100; i++)
- {
- pa_context_state_t st = pa_context_get_state(m_ctx);
- if (st == PA_CONTEXT_READY)
- break;
- if (st == PA_CONTEXT_FAILED || st == PA_CONTEXT_TERMINATED)
- return false;
- if (!pump())
- return false;
- }
-
- if (pa_context_get_state(m_ctx) != PA_CONTEXT_READY)
- return false;
-
- m_source = device;
- if (m_source.isEmpty() || m_source == QLatin1String("default"))
- {
- if (!resolveDefaultSource())
- return false;
- }
-
- // Also establishes the channel count, which setGain() needs.
- double ignored;
- return gain(&ignored);
- }
-
- bool gain(double *out) override
- {
- if (!m_ctx || m_source.isEmpty())
- return false;
-
- const QByteArray name = m_source.toUtf8();
- m_pending = true;
- m_ok = false;
-
- pa_operation *op = pa_context_get_source_info_by_name(m_ctx, name.constData(),
- sourceInfoCb, this);
- if (!await(op))
- return false;
-
- if (m_ok && out)
- *out = m_value;
- return m_ok;
- }
-
- // pa_sw_volume_to_dB() returns -inf for a muted control, which is true but
- // useless as a number to do arithmetic on.
- bool gainDb(double *out) override
- {
- if (!out)
- return false;
-
- double ignored;
- if (!gain(&ignored))
- return false;
-
- if (m_valueDb < -200.0 || m_valueDb > 200.0)
- return false;
-
- *out = m_valueDb;
- return true;
- }
-
- bool setGain(double value) override
- {
- if (!m_ctx || m_source.isEmpty())
- return false;
-
- pa_cvolume cv;
- pa_cvolume_set(&cv, m_channels ? m_channels : 1,
- (pa_volume_t)llround(clampGainAmplified(value) * double(PA_VOLUME_NORM)));
-
- const QByteArray name = m_source.toUtf8();
- m_pending = true;
- m_ok = false;
-
- pa_operation *op = pa_context_set_source_volume_by_name(m_ctx, name.constData(), &cv,
- successCb, this);
- if (!await(op))
- return false;
-
- return m_ok;
- }
-
- QString description() const override
- {
- return m_source + QStringLiteral(" (PulseAudio)");
- }
-
-private:
- bool pump()
- {
- if (pa_mainloop_prepare(m_mainloop, 50 * 1000) < 0)
- return false;
- if (pa_mainloop_poll(m_mainloop) < 0)
- return false;
- if (pa_mainloop_dispatch(m_mainloop) < 0)
- return false;
- return true;
- }
-
- // Runs the loop until the callback for op has fired, then reaps it.
- bool await(pa_operation *op)
- {
- if (!op)
- {
- m_pending = false;
- return false;
- }
-
- for (int i = 0; i < 100 && m_pending; i++)
- {
- if (!pump())
- break;
- }
-
- bool finished = !m_pending;
- m_pending = false;
- pa_operation_unref(op);
- return finished;
- }
-
- bool resolveDefaultSource()
- {
- m_pending = true;
- m_ok = false;
-
- pa_operation *op = pa_context_get_server_info(m_ctx, serverInfoCb, this);
- if (!await(op))
- return false;
-
- return m_ok && !m_source.isEmpty();
- }
-
- static void serverInfoCb(pa_context *, const pa_server_info *info, void *userdata)
- {
- PulseCaptureGain *self = (PulseCaptureGain *)userdata;
-
- if (info && info->default_source_name)
- {
- self->m_source = QString::fromUtf8(info->default_source_name);
- self->m_ok = true;
- }
- self->m_pending = false;
- }
-
- static void sourceInfoCb(pa_context *, const pa_source_info *info, int eol, void *userdata)
- {
- PulseCaptureGain *self = (PulseCaptureGain *)userdata;
-
- if (eol)
- {
- self->m_pending = false;
- return;
- }
-
- if (!info)
- return;
-
- self->m_channels = info->volume.channels;
- // The loudest channel, so a step down is a step down for all of them
- // rather than only for whichever happens to be quietest.
- self->m_value = clampGainAmplified(double(pa_cvolume_max(&info->volume)) / double(PA_VOLUME_NORM));
- self->m_valueDb = pa_sw_volume_to_dB(pa_cvolume_max(&info->volume));
- self->m_ok = true;
- }
-
- static void successCb(pa_context *, int success, void *userdata)
- {
- PulseCaptureGain *self = (PulseCaptureGain *)userdata;
- self->m_ok = (success != 0);
- self->m_pending = false;
- }
-
- pa_mainloop *m_mainloop;
- pa_context *m_ctx;
- QString m_source;
- uint8_t m_channels;
-
- bool m_pending;
- bool m_ok;
- double m_value;
- double m_valueDb;
-};
-
-#endif // HAVE_LIBPULSE
-
-CaptureGainControl *CaptureGainControl::create(const QString &driver, const QString &device)
-{
-#ifdef Q_OS_WIN
- if (driver == QLatin1String("platform-wasapi"))
- return pica_create_wasapi_capture_gain(device);
-#endif
-
-#if defined(Q_OS_MACOS) || defined(Q_OS_MAC)
- if (driver == QLatin1String("platform-coreaudio"))
- return pica_create_coreaudio_capture_gain(device);
-#endif
-
-#ifdef HAVE_LIBPULSE
- if (driver == QLatin1String("pulse"))
- {
- PulseCaptureGain *g = new PulseCaptureGain();
- if (g->open(device))
- return g;
- delete g;
- qWarning() << "No PulseAudio volume control for capture source" << device;
- return nullptr;
- }
-#endif
-
-#ifdef Q_OS_LINUX
- if (driver == QLatin1String("alsa"))
- {
- AlsaCaptureGain *g = new AlsaCaptureGain();
- if (g->open(device))
- return g;
- delete g;
- qWarning() << "No ALSA capture volume control for device" << device;
- return nullptr;
- }
-#endif
-
- Q_UNUSED(driver)
- Q_UNUSED(device)
- return nullptr;
-}
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