alsa: Improve error diagnostics.

Always print the alsa error string corresponding to the failed library
call. This allows to get rid of all but one alsa errors in error.h.

diff --git a/alsa_write.c b/alsa_write.c
index 2dab8fe1543f9205d8d12d7fa9db85be60768df6..e741578c66378d74926c28bea86a56c084bde255 100644 (file)
--- a/alsa_write.c
+++ b/alsa_write.c
@@ -75,44 +75,62 @@ static int alsa_init(struct private_alsa_write_data *pad,
        snd_pcm_uframes_t buffer_size, period_size;
        snd_output_t *log;
        unsigned buffer_time;
-       int err;
+       int ret;
+       const char *msg;
 
        PARA_INFO_LOG("opening %s\n", conf->device_arg);
-       err = snd_pcm_open(&pad->handle, conf->device_arg,
+       msg = "unable to open pcm";
+       ret = snd_pcm_open(&pad->handle, conf->device_arg,
                SND_PCM_STREAM_PLAYBACK, SND_PCM_NONBLOCK);
-       if (err < 0)
-               return -E_PCM_OPEN;
-
+       if (ret < 0)
+               goto fail;
        snd_pcm_hw_params_alloca(&hwparams);
-       snd_pcm_sw_params_alloca(&swparams);
-       if (snd_pcm_hw_params_any(pad->handle, hwparams) < 0)
-               return -E_BROKEN_CONF;
-       if (snd_pcm_hw_params_set_access(pad->handle, hwparams,
-                       SND_PCM_ACCESS_RW_INTERLEAVED) < 0)
-               return -E_ACCESS_TYPE;
-       if (snd_pcm_hw_params_set_format(pad->handle, hwparams,
-                       pad->sample_format) < 0)
-               return -E_SAMPLE_FORMAT;
-       if (snd_pcm_hw_params_set_channels(pad->handle, hwparams,
-                       pad->channels) < 0)
-               return -E_CHANNEL_COUNT;
-       if (snd_pcm_hw_params_set_rate_near(pad->handle, hwparams,
-                       &pad->sample_rate, NULL) < 0)
-               return -E_SET_RATE;
-       err = snd_pcm_hw_params_get_buffer_time_max(hwparams,
+       msg = "Broken alsa configuration";
+       ret = snd_pcm_hw_params_any(pad->handle, hwparams);
+       if (ret < 0)
+               goto fail;
+       msg = "access type not available";
+       ret = snd_pcm_hw_params_set_access(pad->handle, hwparams,
+               SND_PCM_ACCESS_RW_INTERLEAVED);
+       if (ret < 0)
+               goto fail;
+       msg = "sample format not available";
+       ret = snd_pcm_hw_params_set_format(pad->handle, hwparams,
+               pad->sample_format);
+       if (ret < 0)
+               goto fail;
+       msg = "channels count not available";
+       ret = snd_pcm_hw_params_set_channels(pad->handle, hwparams,
+               pad->channels);
+       if (ret < 0)
+               goto fail;
+       msg = "could not set sample rate";
+       ret = snd_pcm_hw_params_set_rate_near(pad->handle, hwparams,
+               &pad->sample_rate, NULL);
+       if (ret < 0)
+               goto fail;
+       msg = "unable to get buffer time";
+       ret = snd_pcm_hw_params_get_buffer_time_max(hwparams, &buffer_time,
+               NULL);
+       if (ret < 0 || buffer_time == 0)
+               goto fail;
+       msg = "could not set buffer time";
+       ret = snd_pcm_hw_params_set_buffer_time_near(pad->handle, hwparams,
                &buffer_time, NULL);
-       if (err < 0 || buffer_time == 0)
-               return -E_GET_BUFFER_TIME;
-       if (snd_pcm_hw_params_set_buffer_time_near(pad->handle, hwparams,
-                       &buffer_time, NULL) < 0)
-               return -E_SET_BUFFER_TIME;
-       if (snd_pcm_hw_params(pad->handle, hwparams) < 0)
-               return -E_HW_PARAMS;
+       if (ret < 0)
+               goto fail;
+       msg = "unable to install hw params";
+       ret = snd_pcm_hw_params(pad->handle, hwparams);
+       if (ret < 0)
+               goto fail;
        snd_pcm_hw_params_get_period_size(hwparams, &period_size, NULL);
        snd_pcm_hw_params_get_buffer_size(hwparams, &buffer_size);
+       msg = "period size equals buffer size";
        if (period_size == buffer_size)
-               return -E_BAD_PERIOD;
+               goto fail;
+
        /* software parameter setup */
+       snd_pcm_sw_params_alloca(&swparams);
        snd_pcm_sw_params_current(pad->handle, swparams);
        snd_pcm_sw_params_set_avail_min(pad->handle, swparams, period_size);
        if (buffer_size < 1)
@@ -120,23 +138,32 @@ static int alsa_init(struct private_alsa_write_data *pad,
        else
                start_threshold = PARA_MIN(buffer_size,
                        (snd_pcm_uframes_t)pad->sample_rate);
-       if (snd_pcm_sw_params_set_start_threshold(pad->handle, swparams,
-                       start_threshold) < 0)
-               return -E_START_THRESHOLD;
+       msg = "could not set start threshold";
+       ret = snd_pcm_sw_params_set_start_threshold(pad->handle, swparams,
+               start_threshold);
+       if (ret < 0)
+               goto fail;
        stop_threshold = buffer_size;
-       if (snd_pcm_sw_params_set_stop_threshold(pad->handle, swparams,
-                       stop_threshold) < 0)
-               return -E_STOP_THRESHOLD;
-       if (snd_pcm_sw_params(pad->handle, swparams) < 0)
-               PARA_WARNING_LOG("unable to install sw params\n");
-       pad->bytes_per_frame = snd_pcm_format_physical_width(pad->sample_format)
-               * pad->channels / 8;
-       if (pad->bytes_per_frame <= 0)
-               return -E_PHYSICAL_WIDTH;
-       if (snd_pcm_nonblock(pad->handle, 1))
-               PARA_ERROR_LOG("failed to set nonblock mode\n");
-       err = snd_output_buffer_open(&log);
-       if (err == 0) {
+       msg = "could not set stop threshold";
+       ret = snd_pcm_sw_params_set_stop_threshold(pad->handle, swparams,
+               stop_threshold);
+       if (ret < 0)
+               goto fail;
+       msg = "unable to install sw params";
+       ret = snd_pcm_sw_params(pad->handle, swparams);
+       if (ret < 0)
+               goto fail;
+       msg = "unable to determine bytes per frame";
+       ret = snd_pcm_format_physical_width(pad->sample_format);
+       if (ret <= 0)
+               goto fail;
+       pad->bytes_per_frame = ret * pad->channels / 8;
+       msg = "failed to set alsa handle to nonblock mode";
+       ret = snd_pcm_nonblock(pad->handle, 1);
+       if (ret < 0)
+               goto fail;
+       ret = snd_output_buffer_open(&log);
+       if (ret == 0) {
                char *buf;
                PARA_INFO_LOG("dumping alsa configuration\n");
                snd_pcm_dump(pad->handle, log);
@@ -152,6 +179,12 @@ static int alsa_init(struct private_alsa_write_data *pad,
                snd_output_close(log);
        }
        return 1;
+fail:
+       if (ret < 0)
+               PARA_ERROR_LOG("%s: %s\n", msg, snd_strerror(-ret));
+       else
+               PARA_ERROR_LOG("%s\n", msg);
+       return -E_ALSA;
 }
 
 static void alsa_write_pre_select(struct sched *s, struct task *t)
@@ -175,8 +208,9 @@ static void alsa_write_pre_select(struct sched *s, struct task *t)
        }
        ret = snd_pcm_poll_descriptors(pad->handle, &pfd, 1);
        if (ret < 0) {
-               PARA_ERROR_LOG("%s\n", snd_strerror(-ret));
-               t->error = -E_ALSA_POLL_FDS;
+               PARA_ERROR_LOG("could not get alsa poll fd: %s\n",
+                       snd_strerror(-ret));
+               t->error = -E_ALSA;
                return;
        }
        pad->poll_fd = pfd.fd;
@@ -285,8 +319,8 @@ again:
                snd_pcm_prepare(pad->handle);
                return;
        }
-       PARA_WARNING_LOG("%s\n", snd_strerror(-frames));
-       ret = -E_ALSA_WRITE;
+       PARA_ERROR_LOG("alsa write error: %s\n", snd_strerror(-frames));
+       ret = -E_ALSA;
 err:
        assert(ret < 0);
        btr_remove_node(btrn);

diff --git a/error.h b/error.h
index 65494131ba518827dc3df6c228ca8d776a01fa71..b3eb7e6edef673e5c6c5929e26c1e9157630c560 100644 (file)
--- a/error.h
+++ b/error.h
@@ -425,21 +425,7 @@ extern const char **para_errlist[];
 
 
 #define ALSA_WRITE_ERRORS \
-       PARA_ERROR(BROKEN_CONF, "Broken alsa configuration"), \
-       PARA_ERROR(ACCESS_TYPE, "alsa access type not available"), \
-       PARA_ERROR(SAMPLE_FORMAT, "sample format not available"), \
-       PARA_ERROR(CHANNEL_COUNT, "channels count not available"), \
-       PARA_ERROR(HW_PARAMS, "unable to install hw params"), \
-       PARA_ERROR(BAD_PERIOD, "can not use period equal to buffer size"), \
-       PARA_ERROR(ALSA_WRITE, "alsa write error"), \
-       PARA_ERROR(PCM_OPEN, "unable to open pcm"), \
-       PARA_ERROR(PHYSICAL_WIDTH, "unable to determine bytes per frame"), \
-       PARA_ERROR(GET_BUFFER_TIME, "snd_pcm_hw_params_get_buffer_time_max() failed"), \
-       PARA_ERROR(SET_BUFFER_TIME, "snd_pcm_hw_params_set_buffer_time_near() failed"), \
-       PARA_ERROR(SET_RATE, "snd_pcm_hw_params_set_rate_near failed"), \
-       PARA_ERROR(START_THRESHOLD, "snd_pcm_sw_params_set_start_threshold() failed"), \
-       PARA_ERROR(STOP_THRESHOLD, "snd_pcm_sw_params_set_stop_threshold() failed"), \
-       PARA_ERROR(ALSA_POLL_FDS, "could not get alsa poll fd"), \
+       PARA_ERROR(ALSA, "alsa error"), \
 
 
 #define WRITE_COMMON_ERRORS \