gBar/src/PulseAudio.h
scorpion-26 0e4b877654 PulseAudio: Make FlushLoop more robust
When PA_CONTEXT_READY is called multiple times, PulseAudio::FlusLoop() would get stuck to to integer underflow.
Now there are multiple things preventing that.

Possible fix for https://github.com/scorpion-26/gBar/issues/7
2023-02-21 21:19:22 +01:00

111 lines
3 KiB
C++

#pragma once
#include "System.h"
#include "Common.h"
#include <pulse/pulseaudio.h>
#include <stdlib.h>
#include <algorithm>
namespace PulseAudio
{
static pa_mainloop* mainLoop;
static pa_context* context;
static int32_t pending = 0;
inline void FlushLoop()
{
while (pending > 0)
{
pa_mainloop_iterate(mainLoop, 0, nullptr);
}
pending = 0;
}
inline void Init()
{
mainLoop = pa_mainloop_new();
pa_mainloop_api* api = pa_mainloop_get_api(mainLoop);
context = pa_context_new(api, "gBar PA context");
int res = pa_context_connect(context, nullptr, PA_CONTEXT_NOAUTOSPAWN, nullptr);
auto stateCallback = [](pa_context* c, void*)
{
switch (pa_context_get_state(c))
{
case PA_CONTEXT_TERMINATED:
case PA_CONTEXT_FAILED:
case PA_CONTEXT_UNCONNECTED: ASSERT(false, "PA Callback error!"); break;
case PA_CONTEXT_AUTHORIZING:
case PA_CONTEXT_SETTING_NAME:
case PA_CONTEXT_CONNECTING:
// Don't care
break;
case PA_CONTEXT_READY:
// Prevent pending from going negative when PA_CONTEXT_READY is called multiple times
if (pending > 0)
pending--;
break;
}
};
pa_context_set_state_callback(context, +stateCallback, nullptr);
pending++;
FlushLoop();
ASSERT(res >= 0, "pa_context_connect failed!");
}
inline System::AudioInfo GetInfo()
{
const char* defaultSink = nullptr;
System::AudioInfo info{};
// 1. Get default sink
auto serverInfo = [](pa_context*, const pa_server_info* info, void* sink)
{
pending--;
*(const char**)sink = info->default_sink_name;
};
pa_context_get_server_info(context, +serverInfo, &defaultSink);
pending++;
FlushLoop();
auto sinkInfo = [](pa_context*, const pa_sink_info* info, int, void* audioInfo)
{
if (!info)
return;
System::AudioInfo* out = (System::AudioInfo*)audioInfo;
double vol = (double)pa_cvolume_avg(&info->volume) / (double)PA_VOLUME_NORM;
out->volume = vol;
out->muted = info->mute;
pending--;
};
pa_context_get_sink_info_by_name(context, defaultSink, +sinkInfo, &info);
pending++;
FlushLoop();
return info;
}
inline void SetVolume(double value)
{
double valClamped = std::clamp(value, 0., 1.);
// I'm too lazy to implement the c api for this. Since it will only be called when needed and doesn't pipe, it shouldn't be a problem to
// fallback for a command
std::string cmd = "pamixer --set-volume " + std::to_string((uint32_t)(valClamped * 100));
system(cmd.c_str());
}
inline void Shutdown()
{
pa_mainloop_free(mainLoop);
}
}