diff options
Diffstat (limited to 'Alsa-Plugin/Alsa-Policy-Hook/PolicyHookCb.c')
| -rw-r--r-- | Alsa-Plugin/Alsa-Policy-Hook/PolicyHookCb.c | 488 |
1 files changed, 488 insertions, 0 deletions
diff --git a/Alsa-Plugin/Alsa-Policy-Hook/PolicyHookCb.c b/Alsa-Plugin/Alsa-Policy-Hook/PolicyHookCb.c new file mode 100644 index 0000000..ae2a5a3 --- /dev/null +++ b/Alsa-Plugin/Alsa-Policy-Hook/PolicyHookCb.c @@ -0,0 +1,488 @@ +/* + * Copyright (C) 2016 "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. + * + * AfbCallBack (snd_ctl_hal_t *handle, int numid, void **response); + * AlsaHookInit is mandatory and called with numid=0 + * + * Syntax in .asoundrc file + * CrlLabel { cb MyFunctionName name "My_Second_Control" } + * + * Testing: + * aplay -DAlsaHook /usr/share/sounds/alsa/test.wav + * + * References: + * https://www.spinics.net/lists/alsa-devel/msg54235.html + * https://github.com/shivdasgujare/utilities/blob/master/nexuss/alsa-scenario-hook/src/alsa-wrapper.c + */ + +#define _GNU_SOURCE +#include <stdio.h> +#include <alsa/asoundlib.h> +#include <alsa/conf.h> +#include <alsa/pcm.h> + +#include <systemd/sd-event.h> +#include <json-c/json.h> + +#include "afb/afb-wsj1.h" +#include "afb/afb-ws-client.h" +#include <pthread.h> +#include <semaphore.h> + + +#define PLUGIN_ENTRY_POINT AlsaInstallHook + // Fulup Note: What ever you may find on Internet you should use + // SND_CONFIG_DLSYM_VERSION_HOOK and not SND_CONFIG_DLSYM_VERSION_HOOK + SND_DLSYM_BUILD_VERSION(PLUGIN_ENTRY_POINT, SND_PCM_DLSYM_VERSION) + +// this should be more than enough +#define MAX_API_CALL 10 + +// timeout in ms +#define REQUEST_DEFAULT_TIMEOUT 100 +#ifndef MAINLOOP_WATCHDOG +#define MAINLOOP_WATCHDOG 60000 +#endif + +// Currently not implemented +#define UNUSED(x) UNUSED_ ## x __attribute__((__unused__)) +#define UNUSED_FUNCTION(x) __attribute__((__unused__)) UNUSED_ ## x +void OnRequestCB(void* UNUSED(handle) , const char* UNUSED(api), const char* UNUSED(verb), struct afb_wsj1_msg*UNUSED(msg)) {} + + typedef struct { + snd_pcm_t *pcm; + const char *uri; + struct afb_wsj1 *wsj1; + sd_event *sdLoop; + int verbose; + sem_t semaphore; + int count; + int error; +} afbClientT; + +typedef struct { + const char *api; + const char *verb; + long timeout; + char *query; + + sd_event_source *evtSource; + char *callIdTag; + afbClientT *afbClient; +} afbRequestT; + +static void *LoopInThread(void *handle) { + afbClientT *afbClient = (afbClientT*) handle; + int count=0; + int watchdog= MAINLOOP_WATCHDOG *1000; + + /* loop until end */ + for (;;) { + + if (afbClient->verbose) printf("ON-MAINLOOP Active count=%d\n", count++); + sd_event_run(afbClient->sdLoop, watchdog); + } + + return NULL; +} + +// lost connect with the AudioDaemon +static void OnHangupCB(void *handle, struct afb_wsj1 *wsj1) { + + afbClientT *afbClient = (afbClientT*) handle; + SNDERR("(Hoops) Lost Connection to %s", afbClient->uri); + + // try to close PCM when impossible terminate client + int err = snd_pcm_close (afbClient->pcm); + if (err) exit(1); +} + +// supported action +typedef enum { + ACTION_PAUSE, + ACTION_START, + ACTION_STOP, + ACTION_RESUME, + + ACTION_NONE +} evtActionEnumT; + +// action label/enum map +const char *evtActionLabels[] ={ + [ACTION_PAUSE] = "pause", + [ACTION_START] = "start", + [ACTION_STOP] = "stop", + [ACTION_RESUME]= "resume", + + [ACTION_NONE]=NULL +}; + +static evtActionEnumT getActionEnum (const char *label) { + int idx; + + if (!label) return ACTION_NONE; + + for (idx = 0; evtActionLabels[idx] != NULL; idx++) { + if (! strcmp(evtActionLabels[idx], label)) break; + } + + if (evtActionLabels[idx]) return idx; + else return ACTION_NONE; +} + +void OnEventCB(void *handle, const char *event, struct afb_wsj1_msg *msg) { + afbClientT *afbClient = (afbClientT*) handle; + json_object *eventJ, *tmpJ, *dataJ; + const char *action; + int err, value, done; + + + eventJ = afb_wsj1_msg_object_j(msg); + done= json_object_object_get_ex(eventJ,"data", &dataJ); + if (!done) { + SNDERR ("PCM_HOOK: uri=%s empty event action", afbClient->uri); + goto OnErrorExit; + } + + json_object_object_get_ex(dataJ,"action", &tmpJ); + action=json_object_get_string(tmpJ); + + json_object_object_get_ex(dataJ,"value", &tmpJ); + value=json_object_get_int(tmpJ); + + switch (getActionEnum(action)) { + case ACTION_PAUSE: + err = snd_pcm_pause (afbClient->pcm, value); + if (err < 0) SNDERR ("PCM_HOOK: Fail to pause value=%d\n", value); + break; + + case ACTION_STOP: + err = snd_pcm_drop (afbClient->pcm); + if (err < 0) SNDERR ("PCM_HOOK: Fail to close\n"); + break; + + case ACTION_START: + err = snd_pcm_resume (afbClient->pcm); + if (err < 0) SNDERR ("PCM_HOOK: Fail to start\n"); + break; + + default: + SNDERR ("PCM_HOOK: Unsupported Event uri=%s action=%s", afbClient->uri, action); + goto OnErrorExit; + } + + if (afbClient->verbose) printf("ON-EVENT action=%s value=%d\n", action, value); + return; + +OnErrorExit: + SNDERR("ON-EVENT %s(%s)\n", event, afb_wsj1_msg_object_s(msg)); + return; +} + +// callback interface for wsj1 +static struct afb_wsj1_itf itf = { + .on_hangup = OnHangupCB, + .on_call = OnRequestCB, + .on_event = OnEventCB +}; + +void OnResponseCB(void *handle, struct afb_wsj1_msg *msg) { + afbRequestT *afbRequest= (afbRequestT*)handle; + + if (afbRequest->afbClient->verbose) printf("ON-RESPONSE call=%s response=%s\n", afbRequest->callIdTag, afb_wsj1_msg_object_s(msg)); + + // Cancel timeout for this request + sd_event_source_unref(afbRequest->evtSource); + + if (! afb_wsj1_msg_is_reply_ok(msg)) goto OnErrorExit; + + // When not more waiting call release semaphore + afbRequest->afbClient->count--; + if (afbRequest->afbClient->count == 0) { + if (afbRequest->afbClient->verbose) printf("ON-RESPONSE No More Waiting Request\n"); + afbRequest->afbClient->error=0; + sem_post (&afbRequest->afbClient->semaphore); + } + return; + +OnErrorExit: + fprintf(stderr, "ON-RESPONSE ERROR call=%s response=%s\n", afbRequest->callIdTag, afb_wsj1_msg_object_s(msg)); + afbRequest->afbClient->error=1; + sem_post (&afbRequest->afbClient->semaphore); +} + +int OnTimeoutCB (sd_event_source* source, uint64_t timer, void* handle) { + afbClientT *afbClient= (afbClientT*)handle; + + SNDERR("\nON-TIMEOUT Call Request Fail URI=%s\n", afbClient->uri); + + // Close PCM and release waiting client + afbClient->error=1; + sem_post (&afbClient->semaphore); + + return 0; +} + +// Call AGL binder asynchronously by with a timeout +static int CallWithTimeout(afbClientT *afbClient, afbRequestT *afbRequest, int count) { + uint64_t usec; + int err; + + // create a unique tag for request + (void) asprintf(&afbRequest->callIdTag, "%d:%s/%s", count, afbRequest->api, afbRequest->verb); + + // create a timer with ~250us accuracy + sd_event_now(afbClient->sdLoop, CLOCK_MONOTONIC, &usec); + sd_event_add_time(afbClient->sdLoop, &afbRequest->evtSource, CLOCK_MONOTONIC, usec+afbRequest->timeout*1000, 250, OnTimeoutCB, afbClient); + + err = afb_wsj1_call_s(afbClient->wsj1, afbRequest->api, afbRequest->verb, afbRequest->query, OnResponseCB, afbRequest); + if (err) goto OnErrorExit; + + // save client handle in request + afbRequest->afbClient = afbClient; + afbClient->count ++; + + return 0; + +OnErrorExit: + return -1; +} + +static int LaunchCallRequest(afbClientT *afbClient, afbRequestT **afbRequest) { + + pthread_t tid; + int err, idx; + + // init waiting counting semaphore + if (sem_init(&afbClient->semaphore, 1, 0) == -1) { + fprintf(stderr, "LaunchCallRequest: Fail Semaphore Init: %s\n", afbClient->uri); + } + + // Create a main loop + err = sd_event_default(&afbClient->sdLoop); + if (err < 0) { + fprintf(stderr, "LaunchCallRequest: Connection to default event loop failed: %s\n", strerror(-err)); + goto OnErrorExit; + } + + // start a thread with a mainloop to monitor Audio-Agent + err = pthread_create(&tid, NULL, &LoopInThread, afbClient); + if (err) goto OnErrorExit; + + // connect the websocket wsj1 to the uri given by the first argument + afbClient->wsj1 = afb_ws_client_connect_wsj1(afbClient->sdLoop, afbClient->uri, &itf, afbClient); + if (afbClient->wsj1 == NULL) { + fprintf(stderr, "LaunchCallRequest: Connection to %s failed\n", afbClient->uri); + goto OnErrorExit; + } + + // send call request to audio-agent asynchronously (respond with thread mainloop context) + for (idx = 0; afbRequest[idx] != NULL; idx++) { + err = CallWithTimeout(afbClient, afbRequest[idx], idx); + if (err) { + fprintf(stderr, "LaunchCallRequest: Fail call %s//%s/%s&%s", afbClient->uri, afbRequest[idx]->api, afbRequest[idx]->verb, afbRequest[idx]->query); + goto OnErrorExit; + } + } + + // launch counter to keep track of waiting request call + afbClient->count=idx; + + return 0; + +OnErrorExit: + return -1; +} + +static int AlsaCloseHook(snd_pcm_hook_t *hook) { + + afbClientT *afbClient = (afbClientT*) snd_pcm_hook_get_private (hook); + + if (afbClient->verbose) fprintf(stdout, "\nAlsaCloseHook pcm=%s\n", snd_pcm_name(afbClient->pcm)); + return 0; +} + +// Function call when Plugin PCM is OPEN +int PLUGIN_ENTRY_POINT (snd_pcm_t *pcm, snd_config_t *conf) { + afbRequestT **afbRequest; + snd_pcm_hook_t *h_close = NULL; + snd_config_iterator_t it, next; + afbClientT *afbClient = malloc(sizeof (afbClientT)); + afbRequest = malloc(MAX_API_CALL * sizeof (afbRequestT)); + int err; + + // start populating client handle + afbClient->pcm = pcm; + afbClient->verbose = 0; + + + // Get PCM arguments from asoundrc + snd_config_for_each(it, next, conf) { + snd_config_t *node = snd_config_iterator_entry(it); + const char *id; + + // ignore comment en empty lines + if (snd_config_get_id(node, &id) < 0) continue; + if (strcmp(id, "comment") == 0 || strcmp(id, "hint") == 0) continue; + + if (strcmp(id, "uri") == 0) { + const char *uri; + if (snd_config_get_string(node, &uri) < 0) { + SNDERR("Invalid String for %s", id); + goto OnErrorExit; + } + afbClient->uri=strdup(uri); + continue; + } + + if (strcmp(id, "verbose") == 0) { + afbClient->verbose= snd_config_get_bool(node); + if (afbClient->verbose < 0) { + SNDERR("Invalid Boolean for %s", id); + goto OnErrorExit; + } + continue; + } + + if (strcmp(id, "request") == 0) { + const char *callConf, *callLabel; + snd_config_type_t ctype; + snd_config_iterator_t currentCall, follow; + snd_config_t *itemConf; + int callCount=0; + + ctype = snd_config_get_type(node); + if (ctype != SND_CONFIG_TYPE_COMPOUND) { + snd_config_get_string(node, &callConf); + SNDERR("Invalid compound type for %s", callConf); + goto OnErrorExit; + } + + + // loop on each call + snd_config_for_each(currentCall, follow, node) { + snd_config_t *ctlconfig = snd_config_iterator_entry(currentCall); + + // ignore empty line + if (snd_config_get_id(ctlconfig, &callLabel) < 0) continue; + + // each clt should be a valid config compound + ctype = snd_config_get_type(ctlconfig); + if (ctype != SND_CONFIG_TYPE_COMPOUND) { + snd_config_get_string(node, &callConf); + SNDERR("Invalid call element for %s", callLabel); + goto OnErrorExit; + } + + // allocate an empty call request + afbRequest[callCount] = calloc(1, sizeof (afbRequestT)); + + + err = snd_config_search(ctlconfig, "api", &itemConf); + if (!err) { + if (snd_config_get_string(itemConf, &afbRequest[callCount]->api) < 0) { + SNDERR("Invalid api string for %s", callLabel); + goto OnErrorExit; + } + } + + err = snd_config_search(ctlconfig, "verb", &itemConf); + if (!err) { + if (snd_config_get_string(itemConf, &afbRequest[callCount]->verb) < 0) { + SNDERR("Invalid verb string %s", id); + goto OnErrorExit; + } + } + + err = snd_config_search(ctlconfig, "timeout", &itemConf); + if (!err) { + if (snd_config_get_integer(itemConf, &afbRequest[callCount]->timeout) < 0) { + SNDERR("Invalid timeout Integer %s", id); + goto OnErrorExit; + } + } + + err = snd_config_search(ctlconfig, "query", &itemConf); + if (!err) { + const char *query; + if (snd_config_get_string(itemConf, &query) < 0) { + SNDERR("Invalid query string %s", id); + goto OnErrorExit; + } + // cleanup string for json_tokener + afbRequest[callCount]->query = strdup(query); + for (int idx = 0; query[idx] != '\0'; idx++) { + if (query[idx] == '\'') afbRequest[callCount]->query[idx] = '"'; + else afbRequest[callCount]->query[idx] = query[idx]; + } + json_object *queryJ = json_tokener_parse(query); + if (!queryJ) { + SNDERR("Invalid Json %s query=%s format \"{'tok1':'val1', 'tok2':'val2'}\" ", id, query); + goto OnErrorExit; + } + } + + // Simple check on call request validity + if (!afbRequest[callCount]->query) afbRequest[callCount]->query= ""; + if (!afbRequest[callCount]->timeout) afbRequest[callCount]->timeout=REQUEST_DEFAULT_TIMEOUT ; + if (!afbRequest[callCount]->verb || !afbRequest[callCount]->api) { + SNDERR("Missing api/verb %s in asoundrc", callLabel); + goto OnErrorExit; + } + + // move to next call if any + callCount ++; + if (callCount == MAX_API_CALL) { + SNDERR("Too Many call MAX_API_CALL=%d", MAX_API_CALL); + goto OnErrorExit; + } + afbRequest[callCount]=NULL; // afbRequest array is NULL terminated + + } + continue; + } + } + + if (afbClient->verbose) fprintf(stdout, "\nAlsaHook Install Start PCM=%s URI=%s\n", snd_pcm_name(afbClient->pcm), afbClient->uri); + + err = snd_pcm_hook_add(&h_close, afbClient->pcm, SND_PCM_HOOK_TYPE_CLOSE, AlsaCloseHook, afbClient); + if (err < 0) goto OnErrorExit; + + // launch call request and create a waiting mainloop thread + err = LaunchCallRequest(afbClient, afbRequest); + if (err < 0) { + fprintf (stderr, "PCM Fail to Enter Mainloop\n"); + goto OnErrorExit; + } + + // wait for all call request to return + sem_wait(&afbClient->semaphore); + if (afbClient->error) { + fprintf (stderr, "PCM Authorisation from Audio Agent Refused\n"); + goto OnErrorExit; + } + + if (afbClient->verbose) fprintf(stdout, "\nAlsaHook Install Success PCM=%s URI=%s\n", snd_pcm_name(afbClient->pcm), afbClient->uri); + return 0; + +OnErrorExit: + fprintf(stderr, "\nAlsaPcmHook Plugin Install Fail PCM=%s\n", snd_pcm_name(afbClient->pcm)); + if (h_close) + snd_pcm_hook_remove(h_close); + + return -EINVAL; +} + |