1 files changed, 364 insertions, 0 deletions
diff --git a/src/VBox/Devices/Audio/DrvHostAudioAlsaStubs.cpp b/src/VBox/Devices/Audio/DrvHostAudioAlsaStubs.cpp
new file mode 100644
index 00000000..70d6b9c1
--- /dev/null
+++ b/src/VBox/Devices/Audio/DrvHostAudioAlsaStubs.cpp
@@ -0,0 +1,364 @@
+/* $Id: DrvHostAudioAlsaStubs.cpp $ */
+/** @file
+ * Stubs for libasound.
+ */
+
+/*
+ * Copyright (C) 2006-2022 Oracle and/or its affiliates.
+ *
+ * This file is part of VirtualBox base platform packages, as
+ * available from https://www.virtualbox.org.
+ *
+ * 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, in version 3 of the
+ * License.
+ *
+ * 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>.
+ *
+ * SPDX-License-Identifier: GPL-3.0-only
+ */
+
+#define LOG_GROUP LOG_GROUP_DRV_HOST_AUDIO
+#include <iprt/assert.h>
+#include <iprt/err.h>
+#include <iprt/ldr.h>
+#include <VBox/log.h>
+#include <iprt/once.h>
+
+#include <alsa/asoundlib.h>
+#include <errno.h>
+
+#include "DrvHostAudioAlsaStubs.h"
+
+#define VBOX_ALSA_LIB "libasound.so.2"
+
+#define PROXY_STUB(function, rettype, signature, shortsig) \
+    static rettype (*pfn_ ## function) signature; \
+    \
+    extern "C" rettype VBox_##function signature; \
+    rettype VBox_##function signature \
+    { \
+        return pfn_ ## function shortsig; \
+    }
+
+PROXY_STUB(snd_lib_error_set_handler, int, (snd_lib_error_handler_t handler),
+           (handler))
+PROXY_STUB(snd_strerror, const char *, (int errnum), (errnum))
+
+PROXY_STUB(snd_device_name_hint, int,
+           (int card, const char *iface, void ***hints),
+           (card, iface, hints))
+PROXY_STUB(snd_device_name_free_hint, int,
+           (void **hints),
+           (hints))
+PROXY_STUB(snd_device_name_get_hint, char *,
+           (const void *hint, const char *id),
+           (hint, id))
+
+static int fallback_snd_device_name_hint(int card, const char *iface, void ***hints)
+{
+    RT_NOREF(card, iface);
+    *hints = NULL;
+    return -ENOSYS;
+}
+
+static int   fallback_snd_device_name_free_hint(void **hints)
+{
+    RT_NOREF(hints);
+    return 0;
+}
+
+static char *fallback_snd_device_name_get_hint(const void *hint, const char *id)
+{
+    RT_NOREF(hint, id);
+    return NULL;
+}
+
+/*
+ * PCM
+ */
+
+PROXY_STUB(snd_pcm_avail_update, snd_pcm_sframes_t, (snd_pcm_t *pcm), (pcm))
+PROXY_STUB(snd_pcm_avail_delay, int,
+           (snd_pcm_t *pcm, snd_pcm_sframes_t *availp, snd_pcm_sframes_t *delayp),
+           (pcm, availp, delayp))
+PROXY_STUB(snd_pcm_close, int, (snd_pcm_t *pcm), (pcm))
+PROXY_STUB(snd_pcm_delay, int, (snd_pcm_t *pcm, snd_pcm_sframes_t *delayp), (pcm, delayp))
+PROXY_STUB(snd_pcm_nonblock, int, (snd_pcm_t *pcm, int *onoff),
+           (pcm, onoff))
+PROXY_STUB(snd_pcm_drain, int, (snd_pcm_t *pcm),
+           (pcm))
+PROXY_STUB(snd_pcm_drop, int, (snd_pcm_t *pcm), (pcm))
+PROXY_STUB(snd_pcm_open, int,
+           (snd_pcm_t **pcm, const char *name, snd_pcm_stream_t stream, int mode),
+           (pcm, name, stream, mode))
+PROXY_STUB(snd_pcm_prepare, int, (snd_pcm_t *pcm), (pcm))
+PROXY_STUB(snd_pcm_readi, snd_pcm_sframes_t,
+           (snd_pcm_t *pcm, void *buffer, snd_pcm_uframes_t size),
+           (pcm, buffer, size))
+PROXY_STUB(snd_pcm_resume, int, (snd_pcm_t *pcm), (pcm))
+PROXY_STUB(snd_pcm_set_chmap, int, (snd_pcm_t *pcm, snd_pcm_chmap_t const *map), (pcm, map))
+PROXY_STUB(snd_pcm_state, snd_pcm_state_t, (snd_pcm_t *pcm), (pcm))
+PROXY_STUB(snd_pcm_state_name, const char *, (snd_pcm_state_t state), (state))
+PROXY_STUB(snd_pcm_writei, snd_pcm_sframes_t,
+           (snd_pcm_t *pcm, const void *buffer, snd_pcm_uframes_t size),
+           (pcm, buffer, size))
+PROXY_STUB(snd_pcm_start, int, (snd_pcm_t *pcm), (pcm))
+
+static int fallback_snd_pcm_avail_delay(snd_pcm_t *pcm, snd_pcm_sframes_t *availp, snd_pcm_sframes_t *delayp)
+{
+    *availp = pfn_snd_pcm_avail_update(pcm);
+    int ret = pfn_snd_pcm_delay(pcm, delayp);
+    if (ret >= 0 && *availp < 0)
+        ret = (int)*availp;
+    return ret;
+}
+
+static int fallback_snd_pcm_set_chmap(snd_pcm_t *pcm, snd_pcm_chmap_t const *map)
+{
+    RT_NOREF(pcm, map);
+    return 0;
+}
+
+/*
+ * HW
+ */
+
+PROXY_STUB(snd_pcm_hw_params, int,
+           (snd_pcm_t *pcm, snd_pcm_hw_params_t *params),
+           (pcm, params))
+PROXY_STUB(snd_pcm_hw_params_any, int,
+           (snd_pcm_t *pcm, snd_pcm_hw_params_t *params),
+           (pcm, params))
+PROXY_STUB(snd_pcm_hw_params_get_buffer_size, int,
+           (const snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val),
+           (params, val))
+PROXY_STUB(snd_pcm_hw_params_get_buffer_size_min, int,
+           (const snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val),
+           (params, val))
+PROXY_STUB(snd_pcm_hw_params_get_period_size, int,
+           (const snd_pcm_hw_params_t *params, snd_pcm_uframes_t *frames, int *dir),
+           (params, frames, dir))
+PROXY_STUB(snd_pcm_hw_params_get_period_size_min, int,
+           (const snd_pcm_hw_params_t *params, snd_pcm_uframes_t *frames, int *dir),
+           (params, frames, dir))
+PROXY_STUB(snd_pcm_hw_params_set_rate_near, int,
+           (snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir),
+           (pcm, params, val, dir))
+PROXY_STUB(snd_pcm_hw_params_set_access, int,
+           (snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_access_t _access),
+           (pcm, params, _access))
+PROXY_STUB(snd_pcm_hw_params_set_buffer_time_near, int,
+           (snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir),
+           (pcm, params, val, dir))
+PROXY_STUB(snd_pcm_hw_params_set_buffer_size_near, int,
+           (snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val),
+           (pcm, params, val))
+PROXY_STUB(snd_pcm_hw_params_set_channels_near, int,
+           (snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val),
+           (pcm, params, val))
+PROXY_STUB(snd_pcm_hw_params_set_period_size_near, int,
+           (snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_uframes_t *val, int *dir),
+           (pcm, params, val, dir))
+PROXY_STUB(snd_pcm_hw_params_set_period_time_near, int,
+           (snd_pcm_t *pcm, snd_pcm_hw_params_t *params, unsigned int *val, int *dir),
+           (pcm, params, val, dir))
+PROXY_STUB(snd_pcm_hw_params_sizeof, size_t, (void), ())
+PROXY_STUB(snd_pcm_hw_params_set_format, int,
+           (snd_pcm_t *pcm, snd_pcm_hw_params_t *params, snd_pcm_format_t val),
+           (pcm, params, val))
+
+/*
+ * SW
+ */
+
+PROXY_STUB(snd_pcm_sw_params, int,
+           (snd_pcm_t *pcm, snd_pcm_sw_params_t *params),
+           (pcm, params))
+PROXY_STUB(snd_pcm_sw_params_current, int,
+           (snd_pcm_t *pcm, snd_pcm_sw_params_t *params),
+           (pcm, params))
+PROXY_STUB(snd_pcm_sw_params_get_start_threshold, int,
+           (const snd_pcm_sw_params_t *params, snd_pcm_uframes_t *val),
+           (params, val))
+PROXY_STUB(snd_pcm_sw_params_set_avail_min, int,
+           (snd_pcm_t *pcm, snd_pcm_sw_params_t *params, snd_pcm_uframes_t val),
+           (pcm, params, val))
+PROXY_STUB(snd_pcm_sw_params_set_start_threshold, int,
+           (snd_pcm_t *pcm, snd_pcm_sw_params_t *params, snd_pcm_uframes_t val),
+           (pcm, params, val))
+PROXY_STUB(snd_pcm_sw_params_sizeof, size_t, (void), ())
+
+/*
+ * Mixer
+ */
+
+PROXY_STUB(snd_mixer_selem_id_sizeof, size_t,
+           (void), ())
+PROXY_STUB(snd_mixer_open, int,
+           (snd_mixer_t **mixer, int mode),
+           (mixer, mode))
+PROXY_STUB(snd_mixer_attach, int,
+           (snd_mixer_t *mixer, const char *name),
+           (mixer, name))
+PROXY_STUB(snd_mixer_close, int,
+           (snd_mixer_t *mixer),
+           (mixer))
+PROXY_STUB(snd_mixer_selem_id_set_index, void,
+           (snd_mixer_selem_id_t *obj, unsigned int val),
+           (obj, val))
+PROXY_STUB(snd_mixer_selem_id_set_name, void,
+           (snd_mixer_selem_id_t *obj, const char *val),
+           (obj, val))
+PROXY_STUB(snd_mixer_selem_set_playback_volume, int,
+           (snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, long value),
+           (elem, channel, value))
+PROXY_STUB(snd_mixer_selem_get_playback_volume_range, int,
+           (snd_mixer_elem_t *elem, long *min, long *max),
+           (elem, min, max))
+PROXY_STUB(snd_mixer_selem_set_capture_volume, int,
+           (snd_mixer_elem_t *elem, snd_mixer_selem_channel_id_t channel, long value),
+           (elem, channel, value))
+PROXY_STUB(snd_mixer_selem_get_capture_volume_range, int,
+           (snd_mixer_elem_t *elem, long *min, long *max),
+           (elem, min, max))
+PROXY_STUB(snd_mixer_selem_register, int,
+           (snd_mixer_t *mixer, snd_mixer_selem_regopt *options, snd_mixer_class_t **classp),
+           (mixer, options, classp))
+PROXY_STUB(snd_mixer_load, int,
+           (snd_mixer_t *mixer),
+           (mixer))
+PROXY_STUB(snd_mixer_find_selem, snd_mixer_elem_t *,
+           (snd_mixer_t *mixer, const snd_mixer_selem_id_t *id),
+           (mixer, id))
+
+typedef struct
+{
+    const char *name;
+    void (**pfn)(void);
+    void (*pfnFallback)(void);
+} SHARED_FUNC;
+
+#define ELEMENT(function) { #function , (void (**)(void)) & pfn_ ## function, NULL }
+#define ELEMENT_FALLBACK(function) { #function , (void (**)(void)) & pfn_ ## function, (void (*)(void))fallback_ ## function }
+static SHARED_FUNC SharedFuncs[] =
+{
+    ELEMENT(snd_lib_error_set_handler),
+    ELEMENT(snd_strerror),
+
+    ELEMENT_FALLBACK(snd_device_name_hint),
+    ELEMENT_FALLBACK(snd_device_name_get_hint),
+    ELEMENT_FALLBACK(snd_device_name_free_hint),
+
+    ELEMENT(snd_pcm_avail_update),
+    ELEMENT_FALLBACK(snd_pcm_avail_delay),
+    ELEMENT(snd_pcm_close),
+    ELEMENT(snd_pcm_delay),
+    ELEMENT(snd_pcm_drain),
+    ELEMENT(snd_pcm_drop),
+    ELEMENT(snd_pcm_nonblock),
+    ELEMENT(snd_pcm_open),
+    ELEMENT(snd_pcm_prepare),
+    ELEMENT(snd_pcm_resume),
+    ELEMENT_FALLBACK(snd_pcm_set_chmap),
+    ELEMENT(snd_pcm_state),
+    ELEMENT(snd_pcm_state_name),
+
+    ELEMENT(snd_pcm_readi),
+    ELEMENT(snd_pcm_start),
+    ELEMENT(snd_pcm_writei),
+
+    ELEMENT(snd_pcm_hw_params),
+    ELEMENT(snd_pcm_hw_params_any),
+    ELEMENT(snd_pcm_hw_params_sizeof),
+    ELEMENT(snd_pcm_hw_params_get_buffer_size),
+    ELEMENT(snd_pcm_hw_params_get_buffer_size_min),
+    ELEMENT(snd_pcm_hw_params_get_period_size_min),
+    ELEMENT(snd_pcm_hw_params_set_access),
+    ELEMENT(snd_pcm_hw_params_set_buffer_size_near),
+    ELEMENT(snd_pcm_hw_params_set_buffer_time_near),
+    ELEMENT(snd_pcm_hw_params_set_channels_near),
+    ELEMENT(snd_pcm_hw_params_set_format),
+    ELEMENT(snd_pcm_hw_params_get_period_size),
+    ELEMENT(snd_pcm_hw_params_set_period_size_near),
+    ELEMENT(snd_pcm_hw_params_set_period_time_near),
+    ELEMENT(snd_pcm_hw_params_set_rate_near),
+
+    ELEMENT(snd_pcm_sw_params),
+    ELEMENT(snd_pcm_sw_params_current),
+    ELEMENT(snd_pcm_sw_params_get_start_threshold),
+    ELEMENT(snd_pcm_sw_params_set_avail_min),
+    ELEMENT(snd_pcm_sw_params_set_start_threshold),
+    ELEMENT(snd_pcm_sw_params_sizeof),
+
+    ELEMENT(snd_mixer_selem_id_sizeof),
+    ELEMENT(snd_mixer_open),
+    ELEMENT(snd_mixer_attach),
+    ELEMENT(snd_mixer_close),
+    ELEMENT(snd_mixer_selem_id_set_index),
+    ELEMENT(snd_mixer_selem_id_set_name),
+    ELEMENT(snd_mixer_selem_set_playback_volume),
+    ELEMENT(snd_mixer_selem_get_playback_volume_range),
+    ELEMENT(snd_mixer_selem_set_capture_volume),
+    ELEMENT(snd_mixer_selem_get_capture_volume_range),
+    ELEMENT(snd_mixer_selem_register),
+    ELEMENT(snd_mixer_load),
+    ELEMENT(snd_mixer_find_selem),
+
+};
+#undef ELEMENT
+
+/** Init once. */
+static RTONCE g_AlsaLibInitOnce = RTONCE_INITIALIZER;
+
+
+/** @callback_method_impl{FNRTONCE} */
+static DECLCALLBACK(int32_t) drvHostAudioAlsaLibInitOnce(void *pvUser)
+{
+    RT_NOREF(pvUser);
+    LogFlowFunc(("\n"));
+
+    RTLDRMOD hMod = NIL_RTLDRMOD;
+    int rc = RTLdrLoadSystemEx(VBOX_ALSA_LIB, RTLDRLOAD_FLAGS_NO_UNLOAD, &hMod);
+    if (RT_SUCCESS(rc))
+    {
+        for (uintptr_t i = 0; i < RT_ELEMENTS(SharedFuncs); i++)
+        {
+            rc = RTLdrGetSymbol(hMod, SharedFuncs[i].name, (void **)SharedFuncs[i].pfn);
+            if (RT_SUCCESS(rc))
+            { /* likely */ }
+            else if (SharedFuncs[i].pfnFallback && rc == VERR_SYMBOL_NOT_FOUND)
+                *SharedFuncs[i].pfn = SharedFuncs[i].pfnFallback;
+            else
+            {
+                LogRelFunc(("Failed to load library %s: Getting symbol %s failed: %Rrc\n", VBOX_ALSA_LIB, SharedFuncs[i].name, rc));
+                return rc;
+            }
+        }
+
+        RTLdrClose(hMod);
+    }
+    else
+        LogRelFunc(("Failed to load library %s (%Rrc)\n", VBOX_ALSA_LIB, rc));
+    return rc;
+}
+
+
+/**
+ * Try to dynamically load the ALSA libraries.
+ *
+ * @returns VBox status code.
+ */
+int audioLoadAlsaLib(void)
+{
+    LogFlowFunc(("\n"));
+    return RTOnce(&g_AlsaLibInitOnce, drvHostAudioAlsaLibInitOnce, NULL);
+}
+