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Diffstat (limited to 'indra/media_plugins/winmmshim/winmm_shim.cpp')
-rw-r--r--indra/media_plugins/winmmshim/winmm_shim.cpp219
1 files changed, 0 insertions, 219 deletions
diff --git a/indra/media_plugins/winmmshim/winmm_shim.cpp b/indra/media_plugins/winmmshim/winmm_shim.cpp
deleted file mode 100644
index 78f7a9b0da..0000000000
--- a/indra/media_plugins/winmmshim/winmm_shim.cpp
+++ /dev/null
@@ -1,219 +0,0 @@
-/**
- * @file winmmshim.cpp
- * @brief controls volume level of process by intercepting calls to winmm.dll
- *
- * $LicenseInfo:firstyear=2010&license=viewerlgpl$
- * Second Life Viewer Source Code
- * Copyright (C) 2010-2014, Linden Research, Inc.
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation;
- * version 2.1 of the License only.
- *
- * This library 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
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
- *
- * Linden Research, Inc., 945 Battery Street, San Francisco, CA 94111 USA
- * $/LicenseInfo$
- */
-#include "forwarding_api.h"
-#include <xmmintrin.h>
-#include <map>
-#include <math.h>
-
-using std::wstring;
-
-static float sVolumeLevel = 1.f; // Could be covered by critical section,
-static bool sMute = false; // not needed with atomicity and alignment.
-static CRITICAL_SECTION sCriticalSection;
-
-BOOL APIENTRY DllMain( HMODULE hModule,
- DWORD ul_reason_for_call,
- LPVOID lpReserved
- )
-{
- if (ul_reason_for_call == DLL_PROCESS_ATTACH)
- {
- InitializeCriticalSection(&sCriticalSection);
- }
- return TRUE;
-}
-
-void ll_winmm_shim_initialize(){
- static volatile bool initialized = false;
-
- // do this only once using double-check locking
- if (!initialized)
- {
- EnterCriticalSection(&sCriticalSection);
- if (!initialized)
- { // bind to original winmm.dll
- TCHAR system_path[MAX_PATH];
- TCHAR dll_path[MAX_PATH];
- ::GetSystemDirectory(system_path, MAX_PATH);
-
- // grab winmm.dll from system path, where it should live
- wsprintf(dll_path, "%s\\winmm.dll", system_path);
- HMODULE winmm_handle = ::LoadLibrary(dll_path);
-
- if (winmm_handle != NULL)
- { // we have a dll, let's get out pointers!
- init_function_pointers(winmm_handle);
- ::OutputDebugStringA("WINMM_SHIM.DLL: real winmm.dll initialized successfully\n");
- initialized = true; // Last thing after completing setup
- }
- else
- {
- // failed to initialize real winmm.dll
- ::OutputDebugStringA("WINMM_SHIM.DLL: Failed to initialize real winmm.dll\n");
- }
- }
- LeaveCriticalSection(&sCriticalSection);
- }
-}
-
-
-extern "C"
-{
- // tracks the requested format for a given waveout buffer
- struct WaveOutFormat
- {
- WaveOutFormat(int bits_per_sample)
- : mBitsPerSample(bits_per_sample)
- {}
- int mBitsPerSample;
- };
- typedef std::map<HWAVEOUT, WaveOutFormat*> wave_out_map_t;
- static wave_out_map_t sWaveOuts; // Covered by sCriticalSection
-
- MMRESULT WINAPI waveOutOpen( LPHWAVEOUT phwo, UINT uDeviceID, LPCWAVEFORMATEX pwfx, DWORD_PTR dwCallback, DWORD_PTR dwInstance, DWORD fdwOpen)
- {
- ll_winmm_shim_initialize();
- if (pwfx->wFormatTag != WAVE_FORMAT_PCM
- || (pwfx->wBitsPerSample != 8 && pwfx->wBitsPerSample != 16))
- { // uncompressed 8 and 16 bit sound are the only types we support
- return WAVERR_BADFORMAT;
- }
-
- MMRESULT result = waveOutOpen_orig(phwo, uDeviceID, pwfx, dwCallback, dwInstance, fdwOpen);
- if (result == MMSYSERR_NOERROR
- && ((fdwOpen & WAVE_FORMAT_QUERY) == 0)) // not just querying for format support
- { // remember the requested bits per sample, and associate with the given handle
- WaveOutFormat* wave_outp = new WaveOutFormat(pwfx->wBitsPerSample);
- EnterCriticalSection(&sCriticalSection);
- sWaveOuts.insert(std::make_pair(*phwo, wave_outp));
- LeaveCriticalSection(&sCriticalSection);
- }
- return result;
- }
-
- MMRESULT WINAPI waveOutClose( HWAVEOUT hwo)
- {
- ll_winmm_shim_initialize();
- EnterCriticalSection(&sCriticalSection);
- wave_out_map_t::iterator found_it = sWaveOuts.find(hwo);
- if (found_it != sWaveOuts.end())
- { // forget what we know about this handle
- delete found_it->second;
- sWaveOuts.erase(found_it);
- }
- LeaveCriticalSection(&sCriticalSection);
- return waveOutClose_orig(hwo);
- }
-
- MMRESULT WINAPI waveOutWrite( HWAVEOUT hwo, LPWAVEHDR pwh, UINT cbwh)
- {
- ll_winmm_shim_initialize();
- MMRESULT result = MMSYSERR_NOERROR;
-
- if (sMute)
- { // zero out the audio buffer when muted
- memset(pwh->lpData, 0, pwh->dwBufferLength);
- }
- else if (sVolumeLevel != 1.f)
- { // need to apply volume level
- int bits_per_sample(0);
-
- EnterCriticalSection(&sCriticalSection);
- wave_out_map_t::iterator found_it = sWaveOuts.find(hwo);
- if (found_it != sWaveOuts.end())
- {
- bits_per_sample = found_it->second->mBitsPerSample;
- }
- LeaveCriticalSection(&sCriticalSection);
- if (bits_per_sample)
- {
- switch (bits_per_sample)
- {
- case 8:
- {
- char volume = (char)(sVolumeLevel * 127.f);
- for (unsigned int i = 0; i < pwh->dwBufferLength; i++)
- {
- // unsigned multiply doesn't use most significant bit, so shift by 7 bits
- // to get resulting value back into 8 bits
- pwh->lpData[i] = (pwh->lpData[i] * volume) >> 7;
- }
- break;
- }
- case 16:
- {
- short volume_16 = (short)(sVolumeLevel * 32767.f);
-
- // copy volume level 4 times into 64 bit MMX register
- __m64 volume_64 = _mm_set_pi16(volume_16, volume_16, volume_16, volume_16);
- __m64* sample_64;
- __m64* last_sample_64 = (__m64*)(pwh->lpData + pwh->dwBufferLength - sizeof(__m64));
- // for everything that can be addressed in 64 bit multiples...
- for (sample_64 = (__m64*)pwh->lpData;
- sample_64 <= last_sample_64;
- ++sample_64)
- {
- //...multiply the samples by the volume...
- __m64 scaled_sample = _mm_mulhi_pi16(*sample_64, volume_64);
- // ...and shift left 1 bit since an unsigned multiple loses the most significant bit
- // 0x7FFF * 0x7FFF = 0x3fff0001
- // 0x3fff0001 << 1 = 0x7ffe0002
- // notice that the LSB is always 0...should consider dithering
- *sample_64 = _mm_slli_pi16(scaled_sample, 1);
- }
-
- // the captain has turned off the MMX sign, you are now free to use floating point registers
- _mm_empty();
-
- // finish remaining samples that didn't fit into 64 bit register
- for (short* sample_16 = (short*)sample_64;
- sample_16 < (short*)(pwh->lpData + pwh->dwBufferLength);
- ++sample_16)
- {
- *sample_16 = (*sample_16 * volume_16) >> 15;
- }
-
- break;
- }
- default:
- // don't do anything
- break;
- }
- }
- }
- return waveOutWrite_orig( hwo, pwh, cbwh);
- }
-
- void WINAPI setPluginVolume(float volume)
- {
- sVolumeLevel = volume;
- }
-
- void WINAPI setPluginMute(bool mute)
- {
- sMute = mute;
- }
-}
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