diff options
| -rw-r--r-- | src/pcm.c | 28 |
1 files changed, 20 insertions, 8 deletions
@@ -364,8 +364,10 @@ static int pcm_sync_ptr(struct pcm *pcm, int flags) { if (pcm->sync_ptr) { pcm->sync_ptr->flags = flags; - if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_SYNC_PTR, pcm->sync_ptr) < 0) + if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_SYNC_PTR, pcm->sync_ptr) < 0) { + oops(pcm, errno, "failed to sync mmap ptr"); return -1; + } return 0; } return -1; @@ -870,8 +872,10 @@ int pcm_close(struct pcm *pcm) * - @ref PCM_NOIRQ * - @ref PCM_MONOTONIC * @param config The hardware and software parameters to open the PCM with. - * @returns On success, returns an initialized pcm, ready for reading or writing. - * On error, returns NULL. + * @returns A PCM structure. + * If an error occurs allocating memory for the PCM, NULL is returned. + * Otherwise, client code should check that the PCM opened properly by calling @ref pcm_is_ready. + * If @ref pcm_is_ready, check @ref pcm_get_error for more information. * @ingroup libtinyalsa-pcm */ struct pcm *pcm_open_by_name(const char *name, @@ -902,8 +906,10 @@ struct pcm *pcm_open_by_name(const char *name, * - @ref PCM_NOIRQ * - @ref PCM_MONOTONIC * @param config The hardware and software parameters to open the PCM with. - * @returns On success, returns an initialized pcm, ready for reading or writing. - * On error, returns NULL. + * @returns A PCM structure. + * If an error occurs allocating memory for the PCM, NULL is returned. + * Otherwise, client code should check that the PCM opened properly by calling @ref pcm_is_ready. + * If @ref pcm_is_ready, check @ref pcm_get_error for more information. * @ingroup libtinyalsa-pcm */ struct pcm *pcm_open(unsigned int card, unsigned int device, @@ -1074,13 +1080,17 @@ fail_close: /** Checks if a PCM file has been opened without error. * @param pcm A PCM handle. - * @return If a PCM's file descriptor is not valid, it returns zero. + * May be NULL. + * @return If a PCM's file descriptor is not valid or the pointer is NULL, it returns zero. * Otherwise, the function returns one. * @ingroup libtinyalsa-pcm */ int pcm_is_ready(const struct pcm *pcm) { - return pcm->fd >= 0; + if (pcm != NULL) { + return pcm->fd >= 0; + } + return 0; } /** Links two PCMs. @@ -1249,8 +1259,10 @@ int pcm_mmap_commit(struct pcm *pcm, unsigned int offset, unsigned int frames) /* update the application pointer in userspace and kernel */ pcm_mmap_appl_forward(pcm, frames); ret = pcm_sync_ptr(pcm, 0); - if (ret != 0) + if (ret != 0){ + printf("%d\n", ret); return ret; + } return frames; } |