audio/filter: Add playback filter

src/audio/filter/playback.cpp

@@ -0,0 +1,177 @@
+/**
+ * @file   playback.cpp
+ * @author Martin Piatka     <piatka@cesnet.cz>
+ */
+/*
+ * Copyright (c) 2022 CESNET, z. s. p. o.
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, is permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * 3. Neither the name of CESNET nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software without
+ *    specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING,
+ * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
+ * EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
+ * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+ * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+ * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
+ * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#include "config_unix.h"
+#include "config_win32.h"
+#endif /* HAVE_CONFIG_H */
+
+#include <memory>
+#include <string_view>
+
+#include "debug.h"
+#include "module.h"
+#include "audio/audio_filter.h"
+#include "audio/types.h"
+#include "audio/audio_playback.h" 
+#include "lib_common.h"
+#include "utils/misc.h"
+
+namespace{
+struct Playback_dev_deleter{ void operator()(state_audio_playback *p){ audio_playback_done(p); } };
+using Playback_dev_uniq = std::unique_ptr<state_audio_playback, Playback_dev_deleter>;
+}
+
+struct state_playback{
+        state_playback(struct module *mod) : mod(MODULE_CLASS_DATA, mod, this) {  }
+
+        module_raii mod;
+
+        int bps = 0;
+        int ch_count = 0;
+        int sample_rate = 0;
+
+        Playback_dev_uniq playback_dev;
+
+};
+
+static void usage(){
+        printf("Plays audio using an UltraGrid playback device:\n\n");
+        printf("playback usage:\n");
+        printf("\tplayback:<playback dev>:<dev config>\n\n");
+}
+
+static af_result_code parse_cfg(state_playback *s, std::string_view cfg){
+        auto tok = tokenize(cfg, ':');
+        if(tok.empty() || tok == "help"){
+                usage();
+                return AF_HELP_SHOWN;
+        } 
+
+        auto dev = std::string(tok);
+        auto dev_cfg = std::string(tokenize(cfg, ':'));
+
+        state_audio_playback *tmp_dev;
+        int ret = audio_playback_init(dev.c_str(), dev_cfg.c_str(), &tmp_dev);
+        s->playback_dev.reset(tmp_dev);
+
+        return ret == 0 ? AF_OK : AF_FAILURE;
+}
+
+static af_result_code init(struct module *parent, const char *cfg, void **state){
+        auto s = std::make_unique<state_playback>(parent);
+
+        auto ret = parse_cfg(s.get(), cfg);
+        if(ret == AF_OK)
+                *state = s.release();
+
+        return ret;
+};
+
+static af_result_code configure(void *state,
+                        int in_bps, int in_ch_count, int in_sample_rate)
+{
+        auto s = static_cast<state_playback *>(state);
+
+        s->bps = in_bps;
+        s->ch_count = in_ch_count;
+        s->sample_rate = in_sample_rate;
+
+        if (audio_playback_reconfigure(s->playback_dev.get(), s->bps * 8,
+                                s->ch_count,
+                                s->sample_rate) != TRUE) {
+                return AF_FAILURE;
+        }
+
+        return AF_OK;
+}
+
+static void done(void *state){
+        auto s = static_cast<state_playback *>(state);
+
+        delete s;
+}
+
+static void get_configured(void *state,
+                        int *bps, int *ch_count, int *sample_rate)
+{
+        auto s = static_cast<state_playback *>(state);
+
+        if(bps) *bps = s->bps;
+        if(ch_count) *ch_count = s->ch_count;
+        if(sample_rate) *sample_rate = s->sample_rate;
+}
+
+static af_result_code filter(void *state, struct audio_frame **frame){
+        auto s = static_cast<state_playback *>(state);
+
+        struct message *msg;
+        while ((msg = check_message(s->mod.get()))) {
+                const char *text = ((msg_universal *) msg)->text;
+                if(parse_cfg(s, text) != AF_OK){
+                        free_message(msg, new_response(RESPONSE_BAD_REQUEST, nullptr));
+                        continue;
+                }
+
+                free_message(msg, new_response(RESPONSE_OK, nullptr));
+        }
+
+        auto f = *frame;
+
+        if(f->bps != s->bps || f->ch_count != s->ch_count || f->sample_rate != s->sample_rate){
+                if(configure(state, f->bps, f->ch_count, f->sample_rate) != AF_OK){
+                        return AF_MISCONFIGURED;
+                }
+        }
+
+        audio_playback_put_frame(s->playback_dev.get(), f);
+
+        return AF_OK;
+}
+
+static const struct audio_filter_info audio_filter_playback = {
+        .name = "playback",
+        .init = init,
+        .done = done,
+        .configure = configure,
+        .get_configured_in = get_configured,
+        .get_configured_out = get_configured,
+        .filter = filter,
+};
+
+REGISTER_MODULE(playback, &audio_filter_playback, LIBRARY_CLASS_AUDIO_FILTER, AUDIO_FILTER_ABI_VERSION);