[PATCH] modules - Support graceful audio fallback

[Luke Yelavich]

From: Luke Yelavich <address@hidden>
To: address@hidden

Add support for graceful audio fallback for use with speech modules. This
allows a comma-separated list of possible audio output methods to be set
in the speech-dispatcher configuration file. The audio initialization code will
try each specified method in turn until either an audio output method gets
initialized successfully, or the list of specified audio outputs is tried, and
all fail.
---
 src/modules/module_utils.c |   99 ++++++++++++++++++++++++++++----------------
 1 files changed, 63 insertions(+), 36 deletions(-)

diff --git a/src/modules/module_utils.c b/src/modules/module_utils.c
index 8b5dd7f..67bc59b 100644
--- a/src/modules/module_utils.c
+++ b/src/modules/module_utils.c
@@ -1073,47 +1073,74 @@ module_audio_init_spd(char **status_info)
   char * error;
   GString *info;
   char *module_audio_pars[10];
+  char *outputs;
+  int audio_output_set;
 
   info = g_string_new("");
+  outputs = audio_settings.audio_output_method;
 
     DBG("Openning audio output system");
-    if (!strcmp(audio_settings.audio_output_method, "oss")){
-    DBG("Using OSS audio output method");
-       module_audio_pars[0] = strdup(audio_settings.audio_oss_device);
-        module_audio_pars[1] = NULL;
-        module_audio_id = spd_audio_open(AUDIO_OSS, (void**) 
module_audio_pars, &error);
-        module_audio_output_method = AUDIO_OSS;
+    if (outputs[0]){
+       const char *next = outputs;
+       size_t len;
+
+       do{
+           outputs = next;
+           next = strchr(outputs, ',');
+
+           if (!outputs[0] || outputs[0] == ',')
+               continue;
+
+           len = (next ? ((size_t)(next-outputs)) : strlen(outputs));
+
+           if (len == 3 && strncmp("oss", outputs, len) == 0){
+               DBG("Using OSS audio output method");
+               module_audio_pars[0] = strdup(audio_settings.audio_oss_device);
+               module_audio_pars[1] = NULL;
+               module_audio_id = spd_audio_open(AUDIO_OSS, (void**) 
module_audio_pars, &error);
+               if (module_audio_id){
+                   module_audio_output_method = AUDIO_OSS;
+                   audio_output_set = 1;
+               }
+           } else if (len == 4 && strncmp("alsa", outputs, len) == 0){
+               DBG("Using Alsa audio output method");
+               module_audio_pars[0] = audio_settings.audio_alsa_device;
+               module_audio_pars[1] = NULL;
+               module_audio_id = spd_audio_open(AUDIO_ALSA, (void**) 
module_audio_pars, &error);
+               if (module_audio_id){
+                   module_audio_output_method = AUDIO_ALSA;
+                   audio_output_set = 1;
+               }
+           } else if (len == 3 && strncmp("nas", outputs, len) == 0){
+               DBG("Using NAS audio output method");
+               module_audio_pars[0] = audio_settings.audio_nas_server;
+               module_audio_pars[1] = NULL;
+               module_audio_id = spd_audio_open(AUDIO_NAS, (void**) 
module_audio_pars, &error);
+               if (module_audio_id){
+                   module_audio_output_method = AUDIO_NAS;
+                   audio_output_set = 1;
+               }
+           } else if (len == 5 && strncmp("pulse", outputs, len) == 0){
+               DBG("Using PulseAudio output method");
+               module_audio_pars[0] = (void *) 
audio_settings.audio_pulse_server;
+               module_audio_pars[1] = (void *) 
audio_settings.audio_pulse_max_length;
+               module_audio_pars[2] = (void *) 
audio_settings.audio_pulse_target_length;
+               module_audio_pars[3] = (void *) 
audio_settings.audio_pulse_pre_buffering;
+               module_audio_pars[4] = (void *) 
audio_settings.audio_pulse_min_request;
+               module_audio_pars[5] = NULL;
+               module_audio_id = spd_audio_open(AUDIO_PULSE, (void**) 
module_audio_pars, &error);
+               if (module_audio_id){
+                   module_audio_output_method = AUDIO_PULSE;
+                   audio_output_set = 1;
+               }
+           } else{
+               ABORT("Sound output method specified in configuration not 
supported. "
+                   "Please choose 'oss', 'alsa', 'nas' or 'pulse'.");
+           }
+       } while(next++);
     }
-    else if (!strcmp(audio_settings.audio_output_method, "alsa")){
-       DBG("Using Alsa audio output method");
-       module_audio_pars[0] = audio_settings.audio_alsa_device;
-       module_audio_pars[1] = NULL;
-       module_audio_id = spd_audio_open(AUDIO_ALSA, (void**) 
module_audio_pars, &error);
-       module_audio_output_method = AUDIO_ALSA;
-    }
-    else if (!strcmp(audio_settings.audio_output_method, "nas")){
-       DBG("Using NAS audio output method");
-       module_audio_pars[0] = audio_settings.audio_nas_server;
-       module_audio_pars[1] = NULL;
-       module_audio_id = spd_audio_open(AUDIO_NAS, (void**) module_audio_pars, 
&error);
-       module_audio_output_method = AUDIO_NAS;
-    }
-    else if (!strcmp(audio_settings.audio_output_method, "pulse")){
-       DBG("Using PulseAudio output method");
-       module_audio_pars[0] = (void *) audio_settings.audio_pulse_server;
-       module_audio_pars[1] = (void *) audio_settings.audio_pulse_max_length;
-       module_audio_pars[2] = (void *) 
audio_settings.audio_pulse_target_length;
-       module_audio_pars[3] = (void *) 
audio_settings.audio_pulse_pre_buffering;
-       module_audio_pars[4] = (void *) audio_settings.audio_pulse_min_request;
-       module_audio_pars[5] = NULL;
-        module_audio_id = spd_audio_open(AUDIO_PULSE, (void**) 
module_audio_pars, &error);
-       module_audio_output_method = AUDIO_PULSE;
-    }
-    else{
-       ABORT("Sound output method specified in configuration not supported. "
-             "Please choose 'oss', 'alsa', 'nas' or 'pulse'.");
-    }
-    if (module_audio_id == NULL){
+
+    if (!audio_output_set){
        g_string_append_printf(info, "Opening sound device failed. Reason: %s. 
", error);
        ABORT("Can't open sound device.");
     }
-- 
1.6.3.1