From e904b7da51297b0417df31ab79568c3f1243fb64 Mon Sep 17 00:00:00 2001
From: Fulup Ar Foll <fulup@iot.bzh>
Date: Tue, 8 May 2018 22:12:35 +0200
Subject: Fist AlsaLoop model playing music (work in progress)

---
 plugins/alsa/alsa-utils-bypath.c | 127 +++++++++++++++++++++++++++++++++++++++
 1 file changed, 127 insertions(+)
 create mode 100644 plugins/alsa/alsa-utils-bypath.c

(limited to 'plugins/alsa/alsa-utils-bypath.c')

diff --git a/plugins/alsa/alsa-utils-bypath.c b/plugins/alsa/alsa-utils-bypath.c
new file mode 100644
index 0000000..e4a8833
--- /dev/null
+++ b/plugins/alsa/alsa-utils-bypath.c
@@ -0,0 +1,127 @@
+/*
+ * Copyright (C) 2018 "IoT.bzh"
+ * Author Fulup Ar Foll <fulup@iot.bzh>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+#define _GNU_SOURCE  // needed for vasprintf
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <ctype.h>
+#include <fcntl.h>
+#include <sys/ioctl.h>
+
+#include "alsa-softmixer.h"
+
+// extracted IOCTLs from <alsa/asoundlib.h>
+#define _IOR_HACKED(type,nr,size)       _IOC(_IOC_READ,(type),(nr),size)
+#define SNDRV_CTL_IOCTL_CARD_INFO(size) _IOR_HACKED('U', 0x01, size)
+
+
+// Clone of AlsaLib snd_card_load2 static function
+PUBLIC snd_ctl_card_info_t *AlsaByPathInfo (CtlSourceT *source, const char *devpath) {
+    int open_dev;
+    snd_ctl_card_info_t *cardInfo = malloc(snd_ctl_card_info_sizeof());
+
+    if (!devpath) goto OnErrorExit;
+    
+    open_dev = open(devpath, O_RDONLY);
+    if (open_dev < 0) goto OnErrorExit;
+    
+    int rc = ioctl(open_dev, SNDRV_CTL_IOCTL_CARD_INFO(snd_ctl_card_info_sizeof()), cardInfo);
+    if (rc < 0) {
+        close(open_dev);
+        goto OnErrorExit;
+    }
+        
+    close(open_dev);
+    return cardInfo;
+    
+OnErrorExit:
+    AFB_ApiError(source->api,"AlsaCardInfoByPath: fail to find sndcard by path= %s", devpath);
+    return NULL;
+}
+
+PUBLIC snd_pcm_t* AlsaByPathOpenPcm(CtlSourceT *source, AlsaDevByPathT *dev, snd_pcm_stream_t direction) {
+    char pcmName[32];
+    int error;
+    snd_pcm_t *pcmHandle;
+
+    // get card info from /dev/snd/xxx if not use hw:x,x,x
+    snd_ctl_card_info_t *cardInfo=NULL;
+    if (dev->devpath) cardInfo = AlsaByPathInfo(source, dev->devpath);
+    else if (dev->devid) cardInfo = AlsaCtlGetInfo (source, dev->devid);
+
+    if (!cardInfo) {
+        AFB_ApiError(source->api, "AlsaByPathOpenPcm: fail to find sndcard by path=%s id=%s", dev->devpath, dev->devid);
+        goto OnErrorExit;
+    }
+
+    // extract useful info from cardInfo handle
+    int cardIdx = snd_ctl_card_info_get_card(cardInfo);
+    const char *cardName = snd_ctl_card_info_get_name(cardInfo);
+
+    // build a valid name and open sndcard
+    snprintf(pcmName, sizeof (pcmName), "hw:%i,%i,%i", cardIdx, dev->device, dev->subdev);
+    error = snd_pcm_open(&pcmHandle, pcmName, direction, SND_PCM_NONBLOCK);
+    if (error) {
+        AFB_ApiError(source->api, "AlsaByPathOpenPcm: fail openpcm (hw:%d -> %s name=%i subdev=%d): %s"
+                , cardIdx, cardName, dev->device, dev->subdev, snd_strerror(error));
+        goto OnErrorExit;
+    }
+       
+    return (pcmHandle);
+
+OnErrorExit:
+    return NULL;
+}
+
+PUBLIC snd_ctl_t *AlsaByPathOpenCtl (CtlSourceT *source, AlsaDevByPathT *dev) {
+    int err;
+    char devid[32];
+    snd_ctl_t *handle;
+    
+    // get card info from /dev/snd/xxx if not use hw:x,x,x
+    snd_ctl_card_info_t *cardInfo=NULL;
+    if (dev->devpath) cardInfo = AlsaByPathInfo(source, dev->devpath);
+    else if (dev->devid) cardInfo = AlsaCtlGetInfo (source, dev->devid);
+
+    if (!cardInfo) {
+        AFB_ApiError(source->api, "AlsaByPathOpenCtl: fail to find sndcard by path=%s id=%s", dev->devpath, dev->devid);
+        goto OnErrorExit;
+    }
+    
+    // extract useful info from cardInfo handle
+    int cardIndex = snd_ctl_card_info_get_card(cardInfo);
+    const char *cardId = snd_ctl_card_info_get_id(cardInfo);
+    const char *cardName = snd_ctl_card_info_get_name(cardInfo);
+
+    // build a valid name and open sndcard
+    snprintf(devid, sizeof (devid), "hw:%i", cardIndex);
+    if ((err = snd_ctl_open(&handle, devid, 0)) < 0) {
+        AFB_ApiError(source->api,"control open (hw:%d -> %s): %s", cardIndex, cardName, snd_strerror(err));
+        goto OnErrorExit;
+    }
+
+    AFB_ApiNotice(source->api, "AlsaCtlOpenByPath: sndcard hw:%d id=%s name=%s", cardIndex, cardId, cardName);
+    free (cardInfo);
+    return handle;
+    
+OnErrorExit:
+    return NULL;
+}
-- 
cgit 1.2.3-korg