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Diffstat (limited to 'indra/media_plugins/webkit/linux_volume_catcher.cpp')
| -rw-r--r-- | indra/media_plugins/webkit/linux_volume_catcher.cpp | 483 |
1 files changed, 483 insertions, 0 deletions
diff --git a/indra/media_plugins/webkit/linux_volume_catcher.cpp b/indra/media_plugins/webkit/linux_volume_catcher.cpp new file mode 100644 index 0000000000..2ba28bd4bf --- /dev/null +++ b/indra/media_plugins/webkit/linux_volume_catcher.cpp @@ -0,0 +1,483 @@ +/** + * @file linux_volume_catcher.cpp + * @brief A Linux-specific, PulseAudio-specific hack to detect and volume-adjust new audio sources + * + * @cond + * $LicenseInfo:firstyear=2010&license=viewergpl$ + * + * Copyright (c) 2010, Linden Research, Inc. + * + * Second Life Viewer Source Code + * The source code in this file ("Source Code") is provided by Linden Lab + * to you under the terms of the GNU General Public License, version 2.0 + * ("GPL"), unless you have obtained a separate licensing agreement + * ("Other License"), formally executed by you and Linden Lab. Terms of + * the GPL can be found in doc/GPL-license.txt in this distribution, or + * online at http://secondlife.com/developers/opensource/gplv2 + * + * There are special exceptions to the terms and conditions of the GPL as + * it is applied to this Source Code. View the full text of the exception + * in the file doc/FLOSS-exception.txt in this software distribution, or + * online at http://secondlife.com/developers/opensource/flossexception + * + * By copying, modifying or distributing this software, you acknowledge + * that you have read and understood your obligations described above, + * and agree to abide by those obligations. + * + * ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO + * WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY, + * COMPLETENESS OR PERFORMANCE. + * $/LicenseInfo$ + * @endcond + */ + +/* + The high-level design is as follows: + 1) Connect to the PulseAudio daemon + 2) Watch for the creation of new audio players connecting to the daemon (this includes ALSA clients running on the PulseAudio emulation layer, such as Flash plugins) + 3) Examine any new audio player's PID to see if it belongs to our own process + 4) If so, tell PA to adjust the volume of that audio player ('sink input' in PA parlance) + 5) Keep a list of all living audio players that we care about, adjust the volumes of all of them when we get a new setVolume() call + */ + +#include "linden_common.h" + +#include "linux_volume_catcher.h" + + +#if LL_PULSEAUDIO_ENABLED + +extern "C" { +#include <glib.h> + +#include <pulse/introspect.h> +#include <pulse/context.h> +#include <pulse/subscribe.h> +#include <pulse/glib-mainloop.h> // There's no special reason why we want the *glib* PA mainloop, but the generic polling implementation seems broken. + +#include "apr_pools.h" +#include "apr_dso.h" +} + +//////////////////////////////////////////////////// + +#define DEBUGMSG(...) do {} while(0) +#define INFOMSG(...) do {} while(0) +#define WARNMSG(...) do {} while(0) + +#define LL_PA_SYM(REQUIRED, PASYM, RTN, ...) RTN (*ll##PASYM)(__VA_ARGS__) = NULL +#include "linux_volume_catcher_pa_syms.inc" +#include "linux_volume_catcher_paglib_syms.inc" +#undef LL_PA_SYM + +static bool sSymsGrabbed = false; +static apr_pool_t *sSymPADSOMemoryPool = NULL; +static apr_dso_handle_t *sSymPADSOHandleG = NULL; + +bool grab_pa_syms(std::string pulse_dso_name) +{ + if (sSymsGrabbed) + { + // already have grabbed good syms + return true; + } + + bool sym_error = false; + bool rtn = false; + apr_status_t rv; + apr_dso_handle_t *sSymPADSOHandle = NULL; + +#define LL_PA_SYM(REQUIRED, PASYM, RTN, ...) do{rv = apr_dso_sym((apr_dso_handle_sym_t*)&ll##PASYM, sSymPADSOHandle, #PASYM); if (rv != APR_SUCCESS) {INFOMSG("Failed to grab symbol: %s", #PASYM); if (REQUIRED) sym_error = true;} else DEBUGMSG("grabbed symbol: %s from %p", #PASYM, (void*)ll##PASYM);}while(0) + + //attempt to load the shared library + apr_pool_create(&sSymPADSOMemoryPool, NULL); + + if ( APR_SUCCESS == (rv = apr_dso_load(&sSymPADSOHandle, + pulse_dso_name.c_str(), + sSymPADSOMemoryPool) )) + { + INFOMSG("Found DSO: %s", pulse_dso_name.c_str()); + +#include "linux_volume_catcher_pa_syms.inc" +#include "linux_volume_catcher_paglib_syms.inc" + + if ( sSymPADSOHandle ) + { + sSymPADSOHandleG = sSymPADSOHandle; + sSymPADSOHandle = NULL; + } + + rtn = !sym_error; + } + else + { + INFOMSG("Couldn't load DSO: %s", pulse_dso_name.c_str()); + rtn = false; // failure + } + + if (sym_error) + { + WARNMSG("Failed to find necessary symbols in PulseAudio libraries."); + } +#undef LL_PA_SYM + + sSymsGrabbed = rtn; + return rtn; +} + + +void ungrab_pa_syms() +{ + // should be safe to call regardless of whether we've + // actually grabbed syms. + + if ( sSymPADSOHandleG ) + { + apr_dso_unload(sSymPADSOHandleG); + sSymPADSOHandleG = NULL; + } + + if ( sSymPADSOMemoryPool ) + { + apr_pool_destroy(sSymPADSOMemoryPool); + sSymPADSOMemoryPool = NULL; + } + + // NULL-out all of the symbols we'd grabbed +#define LL_PA_SYM(REQUIRED, PASYM, RTN, ...) do{ll##PASYM = NULL;}while(0) +#include "linux_volume_catcher_pa_syms.inc" +#include "linux_volume_catcher_paglib_syms.inc" +#undef LL_PA_SYM + + sSymsGrabbed = false; +} +//////////////////////////////////////////////////// + +// PulseAudio requires a chain of callbacks with C linkage +extern "C" { + void callback_discovered_sinkinput(pa_context *context, const pa_sink_input_info *i, int eol, void *userdata); + void callback_subscription_alert(pa_context *context, pa_subscription_event_type_t t, uint32_t index, void *userdata); + void callback_context_state(pa_context *context, void *userdata); +} + + +class LinuxVolumeCatcherImpl +{ +public: + LinuxVolumeCatcherImpl(); + ~LinuxVolumeCatcherImpl(); + + void setVolume(F32 volume); + void pump(void); + + // for internal use - can't be private because used from our C callbacks + + bool loadsyms(std::string pulse_dso_name); + void init(); + void cleanup(); + + void update_all_volumes(F32 volume); + void update_index_volume(U32 index, F32 volume); + void connected_okay(); + + std::set<U32> mSinkInputIndices; + std::map<U32,U32> mSinkInputNumChannels; + F32 mDesiredVolume; + pa_glib_mainloop *mMainloop; + pa_context *mPAContext; + bool mConnected; + bool mGotSyms; +}; + +LinuxVolumeCatcherImpl::LinuxVolumeCatcherImpl() + : mDesiredVolume(0.0f), + mMainloop(NULL), + mPAContext(NULL), + mConnected(false), + mGotSyms(false) +{ + init(); +} + +LinuxVolumeCatcherImpl::~LinuxVolumeCatcherImpl() +{ + cleanup(); +} + +bool LinuxVolumeCatcherImpl::loadsyms(std::string pulse_dso_name) +{ + return grab_pa_syms(pulse_dso_name); +} + +void LinuxVolumeCatcherImpl::init() +{ + // try to be as defensive as possible because PA's interface is a + // bit fragile and (for our purposes) we'd rather simply not function + // than crash + + // we cheat and rely upon libpulse-mainloop-glib.so.0 to pull-in + // libpulse.so.0 - this isn't a great assumption, and the two DSOs should + // probably be loaded separately. Our Linux DSO framework needs refactoring, + // we do this sort of thing a lot with practically identical logic... + mGotSyms = loadsyms("libpulse-mainloop-glib.so.0"); + if (!mGotSyms) return; + + mMainloop = llpa_glib_mainloop_new(g_main_context_default()); + if (mMainloop) + { + pa_mainloop_api *api = llpa_glib_mainloop_get_api(mMainloop); + if (api) + { + pa_proplist *proplist = llpa_proplist_new(); + if (proplist) + { + llpa_proplist_sets(proplist, PA_PROP_APPLICATION_ICON_NAME, "multimedia-player"); + llpa_proplist_sets(proplist, PA_PROP_APPLICATION_ID, "com.secondlife.viewer.mediaplugvoladjust"); + llpa_proplist_sets(proplist, PA_PROP_APPLICATION_NAME, "SL Plugin Volume Adjuster"); + llpa_proplist_sets(proplist, PA_PROP_APPLICATION_VERSION, "1"); + + // plain old pa_context_new() is broken! + mPAContext = llpa_context_new_with_proplist(api, NULL, proplist); + llpa_proplist_free(proplist); + } + } + } + + // Now we've set up a PA context and mainloop, try connecting the + // PA context to a PA daemon. + if (mPAContext) + { + llpa_context_set_state_callback(mPAContext, callback_context_state, this); + pa_context_flags_t cflags = (pa_context_flags)0; // maybe add PA_CONTEXT_NOAUTOSPAWN? + if (llpa_context_connect(mPAContext, NULL, cflags, NULL) >= 0) + { + // Okay! We haven't definitely connected, but we + // haven't definitely failed yet. + } + else + { + // Failed to connect to PA manager... we'll leave + // things like that. Perhaps we should try again later. + } + } +} + +void LinuxVolumeCatcherImpl::cleanup() +{ + mConnected = false; + + if (mGotSyms && mPAContext) + { + llpa_context_disconnect(mPAContext); + llpa_context_unref(mPAContext); + } + mPAContext = NULL; + + if (mGotSyms && mMainloop) + { + llpa_glib_mainloop_free(mMainloop); + } + mMainloop = NULL; +} + +void LinuxVolumeCatcherImpl::setVolume(F32 volume) +{ + mDesiredVolume = volume; + + if (!mGotSyms) return; + + if (mConnected && mPAContext) + { + update_all_volumes(mDesiredVolume); + } + + pump(); +} + +void LinuxVolumeCatcherImpl::pump() +{ + gboolean may_block = FALSE; + g_main_context_iteration(g_main_context_default(), may_block); +} + +void LinuxVolumeCatcherImpl::connected_okay() +{ + pa_operation *op; + + // fetch global list of existing sinkinputs + if ((op = llpa_context_get_sink_input_info_list(mPAContext, + callback_discovered_sinkinput, + this))) + { + llpa_operation_unref(op); + } + + // subscribe to future global sinkinput changes + llpa_context_set_subscribe_callback(mPAContext, + callback_subscription_alert, + this); + if ((op = llpa_context_subscribe(mPAContext, (pa_subscription_mask_t) + (PA_SUBSCRIPTION_MASK_SINK_INPUT), + NULL, NULL))) + { + llpa_operation_unref(op); + } +} + +void LinuxVolumeCatcherImpl::update_all_volumes(F32 volume) +{ + for (std::set<U32>::iterator it = mSinkInputIndices.begin(); + it != mSinkInputIndices.end(); ++it) + { + update_index_volume(*it, volume); + } +} + +void LinuxVolumeCatcherImpl::update_index_volume(U32 index, F32 volume) +{ + static pa_cvolume cvol; + llpa_cvolume_set(&cvol, mSinkInputNumChannels[index], + llpa_sw_volume_from_linear(volume)); + + pa_context *c = mPAContext; + uint32_t idx = index; + const pa_cvolume *cvolumep = &cvol; + pa_context_success_cb_t cb = NULL; // okay as null + void *userdata = NULL; // okay as null + + pa_operation *op; + if ((op = llpa_context_set_sink_input_volume(c, idx, cvolumep, cb, userdata))) + { + llpa_operation_unref(op); + } +} + + +void callback_discovered_sinkinput(pa_context *context, const pa_sink_input_info *sii, int eol, void *userdata) +{ + LinuxVolumeCatcherImpl *impl = dynamic_cast<LinuxVolumeCatcherImpl*>((LinuxVolumeCatcherImpl*)userdata); + llassert(impl); + + if (0 == eol) + { + pa_proplist *proplist = sii->proplist; + pid_t sinkpid = atoll(llpa_proplist_gets(proplist, PA_PROP_APPLICATION_PROCESS_ID)); + + if (sinkpid == getpid()) // does the discovered sinkinput belong to this process? + { + bool is_new = (impl->mSinkInputIndices.find(sii->index) == + impl->mSinkInputIndices.end()); + + impl->mSinkInputIndices.insert(sii->index); + impl->mSinkInputNumChannels[sii->index] = sii->channel_map.channels; + + if (is_new) + { + // new! + impl->update_index_volume(sii->index, impl->mDesiredVolume); + } + else + { + // seen it already, do nothing. + } + } + } +} + +void callback_subscription_alert(pa_context *context, pa_subscription_event_type_t t, uint32_t index, void *userdata) +{ + LinuxVolumeCatcherImpl *impl = dynamic_cast<LinuxVolumeCatcherImpl*>((LinuxVolumeCatcherImpl*)userdata); + llassert(impl); + + switch (t & PA_SUBSCRIPTION_EVENT_FACILITY_MASK) { + case PA_SUBSCRIPTION_EVENT_SINK_INPUT: + if ((t & PA_SUBSCRIPTION_EVENT_TYPE_MASK) == + PA_SUBSCRIPTION_EVENT_REMOVE) + { + // forget this sinkinput, if we were caring about it + impl->mSinkInputIndices.erase(index); + impl->mSinkInputNumChannels.erase(index); + } + else + { + // ask for more info about this new sinkinput + pa_operation *op; + if ((op = llpa_context_get_sink_input_info(impl->mPAContext, index, callback_discovered_sinkinput, impl))) + { + llpa_operation_unref(op); + } + } + break; + + default:; + } +} + +void callback_context_state(pa_context *context, void *userdata) +{ + LinuxVolumeCatcherImpl *impl = dynamic_cast<LinuxVolumeCatcherImpl*>((LinuxVolumeCatcherImpl*)userdata); + llassert(impl); + + switch (llpa_context_get_state(context)) + { + case PA_CONTEXT_READY: + impl->mConnected = true; + impl->connected_okay(); + break; + case PA_CONTEXT_TERMINATED: + impl->mConnected = false; + break; + case PA_CONTEXT_FAILED: + impl->mConnected = false; + break; + default:; + } +} + +///////////////////////////////////////////////////// + +LinuxVolumeCatcher::LinuxVolumeCatcher() +{ + pimpl = new LinuxVolumeCatcherImpl(); +} + +LinuxVolumeCatcher::~LinuxVolumeCatcher() +{ + delete pimpl; + pimpl = NULL; +} + +void LinuxVolumeCatcher::setVolume(F32 volume) +{ + llassert(pimpl); + pimpl->setVolume(volume); +} + +void LinuxVolumeCatcher::pump() +{ + llassert(pimpl); + pimpl->pump(); +} + +#else // !LL_PULSEAUDIO_ENABLED + +// stub. + +LinuxVolumeCatcher::LinuxVolumeCatcher() +{ + pimpl = NULL; +} + +LinuxVolumeCatcher::~LinuxVolumeCatcher() +{ +} + +void LinuxVolumeCatcher::setVolume(F32 volume) +{ +} + +void LinuxVolumeCatcher::pump() +{ +} + +#endif // LL_PULSEAUDIO_ENABLED |