diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/Makefile | 45 | ||||
| -rw-r--r-- | src/mixer.c | 565 | ||||
| -rw-r--r-- | src/pcm.c | 1097 |
3 files changed, 1707 insertions, 0 deletions
diff --git a/src/Makefile b/src/Makefile new file mode 100644 index 0000000..1549650 --- /dev/null +++ b/src/Makefile @@ -0,0 +1,45 @@ +TOPDIR ?= .. +SRCDIR ?= $(TOPDIR)/src +INCDIR ?= $(TOPDIR)/include + +DESTDIR ?= +PREFIX ?= /usr/local +CROSS_COMPILE = + +CC = $(CROSS_COMPILE)gcc +CFLAGS = -Wall -Wextra -Werror -Wfatal-errors +CFLAGS += -I $(INCDIR) +CFLAGS += -fPIC + +AR = $(CROSS_COMPILE)ar +ARFLAGS = rcs + +LD = $(CROSS_COMPILE)gcc +LDFLAGS = + +OBJECTS = mixer.o pcm.o + +.PHONY: all +all: libtinyalsa.a libtinyalsa.so + +pcm.o: pcm.c $(INCDIR)/tinyalsa/pcm.h + +mixer.o: mixer.c $(INCDIR)/tinyalsa/mixer.h + +libtinyalsa.a: $(OBJECTS) + $(AR) $(ARFLAGS) $@ $^ + +libtinyalsa.so: $(OBJECTS) + $(LD) $(LDFLAGS) -shared $^ -o $@ + +.PHONY: clean +clean: + rm -f libtinyalsa.a + rm -f libtinyalsa.so + rm -f $(OBJECTS) + +.PHONY: install +install: libtinyalsa.a libtinyalsa.so + cp -u libtinyalsa.a $(DESTDIR)$(PREFIX)/lib/ + cp -u libtinyalsa.so $(DESTDIR)$(PREFIX)/lib/ + diff --git a/src/mixer.c b/src/mixer.c new file mode 100644 index 0000000..ac294ca --- /dev/null +++ b/src/mixer.c @@ -0,0 +1,565 @@ +/* mixer.c +** +** Copyright 2011, The Android Open Source Project +** +** Redistribution and use in source and binary forms, with or without +** modification, are permitted provided that the following conditions are met: +** * Redistributions of source code must retain the above copyright +** notice, this list of conditions and the following disclaimer. +** * Redistributions in binary form must reproduce the above copyright +** notice, this list of conditions and the following disclaimer in the +** documentation and/or other materials provided with the distribution. +** * Neither the name of The Android Open Source Project nor the names of +** its contributors may be used to endorse or promote products derived +** from this software without specific prior written permission. +** +** THIS SOFTWARE IS PROVIDED BY The Android Open Source Project ``AS IS'' AND +** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +** ARE DISCLAIMED. IN NO EVENT SHALL The Android Open Source Project BE LIABLE +** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR +** SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER +** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH +** DAMAGE. +*/ + +#include <stdio.h> +#include <stdlib.h> +#include <stdint.h> +#include <string.h> +#include <unistd.h> +#include <fcntl.h> +#include <errno.h> +#include <ctype.h> +#include <limits.h> +#include <time.h> + +#include <sys/ioctl.h> + +#include <linux/ioctl.h> +#define __force +#define __bitwise +#define __user +#include <sound/asound.h> + +#include <tinyalsa/asoundlib.h> + +struct mixer_ctl { + struct mixer *mixer; + struct snd_ctl_elem_info info; + char **ename; +}; + +struct mixer { + int fd; + struct snd_ctl_card_info card_info; + struct mixer_ctl *ctl; + unsigned int count; +}; + +void mixer_close(struct mixer *mixer) +{ + unsigned int n,m; + + if (!mixer) + return; + + if (mixer->fd >= 0) + close(mixer->fd); + + if (mixer->ctl) { + for (n = 0; n < mixer->count; n++) { + if (mixer->ctl[n].ename) { + unsigned int max = mixer->ctl[n].info.value.enumerated.items; + for (m = 0; m < max; m++) + free(mixer->ctl[n].ename[m]); + free(mixer->ctl[n].ename); + } + } + free(mixer->ctl); + } + + free(mixer); + + /* TODO: verify frees */ +} + +struct mixer *mixer_open(unsigned int card) +{ + struct snd_ctl_elem_list elist; + struct snd_ctl_elem_info tmp; + struct snd_ctl_elem_id *eid = NULL; + struct mixer *mixer = NULL; + unsigned int n, m; + int fd; + char fn[256]; + + snprintf(fn, sizeof(fn), "/dev/snd/controlC%u", card); + fd = open(fn, O_RDWR); + if (fd < 0) + return 0; + + memset(&elist, 0, sizeof(elist)); + if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_LIST, &elist) < 0) + goto fail; + + mixer = calloc(1, sizeof(*mixer)); + if (!mixer) + goto fail; + + mixer->ctl = calloc(elist.count, sizeof(struct mixer_ctl)); + if (!mixer->ctl) + goto fail; + + if (ioctl(fd, SNDRV_CTL_IOCTL_CARD_INFO, &mixer->card_info) < 0) + goto fail; + + eid = calloc(elist.count, sizeof(struct snd_ctl_elem_id)); + if (!eid) + goto fail; + + mixer->count = elist.count; + mixer->fd = fd; + elist.space = mixer->count; + elist.pids = eid; + if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_LIST, &elist) < 0) + goto fail; + + for (n = 0; n < mixer->count; n++) { + struct snd_ctl_elem_info *ei = &mixer->ctl[n].info; + ei->id.numid = eid[n].numid; + if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_INFO, ei) < 0) + goto fail; + mixer->ctl[n].mixer = mixer; + if (ei->type == SNDRV_CTL_ELEM_TYPE_ENUMERATED) { + char **enames = calloc(ei->value.enumerated.items, sizeof(char*)); + if (!enames) + goto fail; + mixer->ctl[n].ename = enames; + for (m = 0; m < ei->value.enumerated.items; m++) { + memset(&tmp, 0, sizeof(tmp)); + tmp.id.numid = ei->id.numid; + tmp.value.enumerated.item = m; + if (ioctl(fd, SNDRV_CTL_IOCTL_ELEM_INFO, &tmp) < 0) + goto fail; + enames[m] = strdup(tmp.value.enumerated.name); + if (!enames[m]) + goto fail; + } + } + } + + free(eid); + return mixer; + +fail: + /* TODO: verify frees in failure case */ + if (eid) + free(eid); + if (mixer) + mixer_close(mixer); + else if (fd >= 0) + close(fd); + return 0; +} + +const char *mixer_get_name(struct mixer *mixer) +{ + return (const char *)mixer->card_info.name; +} + +unsigned int mixer_get_num_ctls(struct mixer *mixer) +{ + if (!mixer) + return 0; + + return mixer->count; +} + +struct mixer_ctl *mixer_get_ctl(struct mixer *mixer, unsigned int id) +{ + if (mixer && (id < mixer->count)) + return mixer->ctl + id; + + return NULL; +} + +struct mixer_ctl *mixer_get_ctl_by_name(struct mixer *mixer, const char *name) +{ + return mixer_get_ctl_by_name_and_index(mixer, name, 0); +} + +struct mixer_ctl *mixer_get_ctl_by_name_and_index(struct mixer *mixer, + const char *name, + unsigned int index) +{ + unsigned int n; + struct mixer_ctl *ctl; + + if (!mixer) + return NULL; + + ctl = mixer->ctl; + + for (n = 0; n < mixer->count; n++) + if (!strcmp(name, (char*) ctl[n].info.id.name)) + if (index-- == 0) + return mixer->ctl + n; + + return NULL; +} + +void mixer_ctl_update(struct mixer_ctl *ctl) +{ + ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_INFO, ctl->info); +} + +unsigned int mixer_ctl_get_id(struct mixer_ctl *ctl) +{ + if (!ctl) + return UINT_MAX; + + /* numid values start at 1, return a 0-base value that + * can be passed to mixer_get_ctl() + */ + return ctl->info.id.numid - 1; +} + +const char *mixer_ctl_get_name(struct mixer_ctl *ctl) +{ + if (!ctl) + return NULL; + + return (const char *)ctl->info.id.name; +} + +enum mixer_ctl_type mixer_ctl_get_type(struct mixer_ctl *ctl) +{ + if (!ctl) + return MIXER_CTL_TYPE_UNKNOWN; + + switch (ctl->info.type) { + case SNDRV_CTL_ELEM_TYPE_BOOLEAN: return MIXER_CTL_TYPE_BOOL; + case SNDRV_CTL_ELEM_TYPE_INTEGER: return MIXER_CTL_TYPE_INT; + case SNDRV_CTL_ELEM_TYPE_ENUMERATED: return MIXER_CTL_TYPE_ENUM; + case SNDRV_CTL_ELEM_TYPE_BYTES: return MIXER_CTL_TYPE_BYTE; + case SNDRV_CTL_ELEM_TYPE_IEC958: return MIXER_CTL_TYPE_IEC958; + case SNDRV_CTL_ELEM_TYPE_INTEGER64: return MIXER_CTL_TYPE_INT64; + default: return MIXER_CTL_TYPE_UNKNOWN; + }; +} + +const char *mixer_ctl_get_type_string(struct mixer_ctl *ctl) +{ + if (!ctl) + return ""; + + switch (ctl->info.type) { + case SNDRV_CTL_ELEM_TYPE_BOOLEAN: return "BOOL"; + case SNDRV_CTL_ELEM_TYPE_INTEGER: return "INT"; + case SNDRV_CTL_ELEM_TYPE_ENUMERATED: return "ENUM"; + case SNDRV_CTL_ELEM_TYPE_BYTES: return "BYTE"; + case SNDRV_CTL_ELEM_TYPE_IEC958: return "IEC958"; + case SNDRV_CTL_ELEM_TYPE_INTEGER64: return "INT64"; + default: return "Unknown"; + }; +} + +unsigned int mixer_ctl_get_num_values(struct mixer_ctl *ctl) +{ + if (!ctl) + return 0; + + return ctl->info.count; +} + +static int percent_to_int(struct snd_ctl_elem_info *ei, int percent) +{ + if ((percent > 100) || (percent < 0)) { + return -EINVAL; + } + + int range = (ei->value.integer.max - ei->value.integer.min); + + return ei->value.integer.min + (range * percent) / 100; +} + +static int int_to_percent(struct snd_ctl_elem_info *ei, int value) +{ + int range = (ei->value.integer.max - ei->value.integer.min); + + if (range == 0) + return 0; + + return ((value - ei->value.integer.min) / range) * 100; +} + +int mixer_ctl_get_percent(struct mixer_ctl *ctl, unsigned int id) +{ + if (!ctl || (ctl->info.type != SNDRV_CTL_ELEM_TYPE_INTEGER)) + return -EINVAL; + + return int_to_percent(&ctl->info, mixer_ctl_get_value(ctl, id)); +} + +int mixer_ctl_set_percent(struct mixer_ctl *ctl, unsigned int id, int percent) +{ + if (!ctl || (ctl->info.type != SNDRV_CTL_ELEM_TYPE_INTEGER)) + return -EINVAL; + + return mixer_ctl_set_value(ctl, id, percent_to_int(&ctl->info, percent)); +} + +int mixer_ctl_get_value(struct mixer_ctl *ctl, unsigned int id) +{ + struct snd_ctl_elem_value ev; + int ret; + + if (!ctl || (id >= ctl->info.count)) + return -EINVAL; + + memset(&ev, 0, sizeof(ev)); + ev.id.numid = ctl->info.id.numid; + ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_READ, &ev); + if (ret < 0) + return ret; + + switch (ctl->info.type) { + case SNDRV_CTL_ELEM_TYPE_BOOLEAN: + return !!ev.value.integer.value[id]; + + case SNDRV_CTL_ELEM_TYPE_INTEGER: + return ev.value.integer.value[id]; + + case SNDRV_CTL_ELEM_TYPE_ENUMERATED: + return ev.value.enumerated.item[id]; + + case SNDRV_CTL_ELEM_TYPE_BYTES: + return ev.value.bytes.data[id]; + + default: + return -EINVAL; + } + + return 0; +} + +int mixer_ctl_get_array(struct mixer_ctl *ctl, void *array, size_t count) +{ + struct snd_ctl_elem_value ev; + int ret = 0; + size_t size; + void *source; + + if (!ctl || (count > ctl->info.count) || !count || !array) + return -EINVAL; + + memset(&ev, 0, sizeof(ev)); + ev.id.numid = ctl->info.id.numid; + + switch (ctl->info.type) { + case SNDRV_CTL_ELEM_TYPE_BOOLEAN: + case SNDRV_CTL_ELEM_TYPE_INTEGER: + ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_READ, &ev); + if (ret < 0) + return ret; + size = sizeof(ev.value.integer.value[0]); + source = ev.value.integer.value; + break; + + case SNDRV_CTL_ELEM_TYPE_BYTES: + /* check if this is new bytes TLV */ + if (ctl->info.access & SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE) { + struct snd_ctl_tlv *tlv; + int ret; + + if (count > SIZE_MAX - sizeof(*tlv)) + return -EINVAL; + tlv = calloc(1, sizeof(*tlv) + count); + if (!tlv) + return -ENOMEM; + tlv->numid = ctl->info.id.numid; + tlv->length = count; + ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_TLV_READ, tlv); + + source = tlv->tlv; + memcpy(array, source, count); + + free(tlv); + + return ret; + } else { + ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_READ, &ev); + if (ret < 0) + return ret; + size = sizeof(ev.value.bytes.data[0]); + source = ev.value.bytes.data; + break; + } + + default: + return -EINVAL; + } + + memcpy(array, source, size * count); + + return 0; +} + +int mixer_ctl_set_value(struct mixer_ctl *ctl, unsigned int id, int value) +{ + struct snd_ctl_elem_value ev; + int ret; + + if (!ctl || (id >= ctl->info.count)) + return -EINVAL; + + memset(&ev, 0, sizeof(ev)); + ev.id.numid = ctl->info.id.numid; + ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_READ, &ev); + if (ret < 0) + return ret; + + switch (ctl->info.type) { + case SNDRV_CTL_ELEM_TYPE_BOOLEAN: + ev.value.integer.value[id] = !!value; + break; + + case SNDRV_CTL_ELEM_TYPE_INTEGER: + if ((value < mixer_ctl_get_range_min(ctl)) || + (value > mixer_ctl_get_range_max(ctl))) { + return -EINVAL; + } + + ev.value.integer.value[id] = value; + break; + + case SNDRV_CTL_ELEM_TYPE_ENUMERATED: + ev.value.enumerated.item[id] = value; + break; + + case SNDRV_CTL_ELEM_TYPE_BYTES: + ev.value.bytes.data[id] = value; + break; + + default: + return -EINVAL; + } + + return ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_WRITE, &ev); +} + +int mixer_ctl_set_array(struct mixer_ctl *ctl, const void *array, size_t count) +{ + struct snd_ctl_elem_value ev; + size_t size; + void *dest; + + if (!ctl || (count > ctl->info.count) || !count || !array) + return -EINVAL; + + memset(&ev, 0, sizeof(ev)); + ev.id.numid = ctl->info.id.numid; + + switch (ctl->info.type) { + case SNDRV_CTL_ELEM_TYPE_BOOLEAN: + case SNDRV_CTL_ELEM_TYPE_INTEGER: + size = sizeof(ev.value.integer.value[0]); + dest = ev.value.integer.value; + break; + + case SNDRV_CTL_ELEM_TYPE_BYTES: + /* check if this is new bytes TLV */ + if (ctl->info.access & SNDRV_CTL_ELEM_ACCESS_TLV_READWRITE) { + struct snd_ctl_tlv *tlv; + int ret = 0; + if (count > SIZE_MAX - sizeof(*tlv)) + return -EINVAL; + tlv = calloc(1, sizeof(*tlv) + count); + if (!tlv) + return -ENOMEM; + tlv->numid = ctl->info.id.numid; + tlv->length = count; + memcpy(tlv->tlv, array, count); + + ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_TLV_WRITE, tlv); + free(tlv); + + return ret; + } else { + size = sizeof(ev.value.bytes.data[0]); + dest = ev.value.bytes.data; + } + break; + + default: + return -EINVAL; + } + + memcpy(dest, array, size * count); + + return ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_WRITE, &ev); +} + +int mixer_ctl_get_range_min(struct mixer_ctl *ctl) +{ + if (!ctl || (ctl->info.type != SNDRV_CTL_ELEM_TYPE_INTEGER)) + return -EINVAL; + + return ctl->info.value.integer.min; +} + +int mixer_ctl_get_range_max(struct mixer_ctl *ctl) +{ + if (!ctl || (ctl->info.type != SNDRV_CTL_ELEM_TYPE_INTEGER)) + return -EINVAL; + + return ctl->info.value.integer.max; +} + +unsigned int mixer_ctl_get_num_enums(struct mixer_ctl *ctl) +{ + if (!ctl) + return 0; + + return ctl->info.value.enumerated.items; +} + +const char *mixer_ctl_get_enum_string(struct mixer_ctl *ctl, + unsigned int enum_id) +{ + if (!ctl || (ctl->info.type != SNDRV_CTL_ELEM_TYPE_ENUMERATED) || + (enum_id >= ctl->info.value.enumerated.items)) + return NULL; + + return (const char *)ctl->ename[enum_id]; +} + +int mixer_ctl_set_enum_by_string(struct mixer_ctl *ctl, const char *string) +{ + unsigned int i, num_enums; + struct snd_ctl_elem_value ev; + int ret; + + if (!ctl || (ctl->info.type != SNDRV_CTL_ELEM_TYPE_ENUMERATED)) + return -EINVAL; + + num_enums = ctl->info.value.enumerated.items; + for (i = 0; i < num_enums; i++) { + if (!strcmp(string, ctl->ename[i])) { + memset(&ev, 0, sizeof(ev)); + ev.value.enumerated.item[0] = i; + ev.id.numid = ctl->info.id.numid; + ret = ioctl(ctl->mixer->fd, SNDRV_CTL_IOCTL_ELEM_WRITE, &ev); + if (ret < 0) + return ret; + return 0; + } + } + + return -EINVAL; +} + diff --git a/src/pcm.c b/src/pcm.c new file mode 100644 index 0000000..24ab333 --- /dev/null +++ b/src/pcm.c @@ -0,0 +1,1097 @@ +/* pcm.c +** +** Copyright 2011, The Android Open Source Project +** +** Redistribution and use in source and binary forms, with or without +** modification, are permitted provided that the following conditions are met: +** * Redistributions of source code must retain the above copyright +** notice, this list of conditions and the following disclaimer. +** * Redistributions in binary form must reproduce the above copyright +** notice, this list of conditions and the following disclaimer in the +** documentation and/or other materials provided with the distribution. +** * Neither the name of The Android Open Source Project nor the names of +** its contributors may be used to endorse or promote products derived +** from this software without specific prior written permission. +** +** THIS SOFTWARE IS PROVIDED BY The Android Open Source Project ``AS IS'' AND +** ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +** IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +** ARE DISCLAIMED. IN NO EVENT SHALL The Android Open Source Project BE LIABLE +** FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +** DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR +** SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER +** CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +** LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +** OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH +** DAMAGE. +*/ + +#include <stdio.h> +#include <stdlib.h> +#include <fcntl.h> +#include <stdarg.h> +#include <string.h> +#include <errno.h> +#include <unistd.h> +#include <poll.h> + +#include <sys/ioctl.h> +#include <sys/mman.h> +#include <sys/time.h> +#include <time.h> +#include <limits.h> + +#include <linux/ioctl.h> +#define __force +#define __bitwise +#define __user +#include <sound/asound.h> + +#include <tinyalsa/asoundlib.h> + +#define PARAM_MAX SNDRV_PCM_HW_PARAM_LAST_INTERVAL +#define SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP (1<<2) + +static inline int param_is_mask(int p) +{ + return (p >= SNDRV_PCM_HW_PARAM_FIRST_MASK) && + (p <= SNDRV_PCM_HW_PARAM_LAST_MASK); +} + +static inline int param_is_interval(int p) +{ + return (p >= SNDRV_PCM_HW_PARAM_FIRST_INTERVAL) && + (p <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL); +} + +static inline struct snd_interval *param_to_interval(struct snd_pcm_hw_params *p, int n) +{ + return &(p->intervals[n - SNDRV_PCM_HW_PARAM_FIRST_INTERVAL]); +} + +static inline struct snd_mask *param_to_mask(struct snd_pcm_hw_params *p, int n) +{ + return &(p->masks[n - SNDRV_PCM_HW_PARAM_FIRST_MASK]); +} + +static void param_set_mask(struct snd_pcm_hw_params *p, int n, unsigned int bit) +{ + if (bit >= SNDRV_MASK_MAX) + return; + if (param_is_mask(n)) { + struct snd_mask *m = param_to_mask(p, n); + m->bits[0] = 0; + m->bits[1] = 0; + m->bits[bit >> 5] |= (1 << (bit & 31)); + } +} + +static void param_set_min(struct snd_pcm_hw_params *p, int n, unsigned int val) +{ + if (param_is_interval(n)) { + struct snd_interval *i = param_to_interval(p, n); + i->min = val; + } +} + +static unsigned int param_get_min(struct snd_pcm_hw_params *p, int n) +{ + if (param_is_interval(n)) { + struct snd_interval *i = param_to_interval(p, n); + return i->min; + } + return 0; +} + +static unsigned int param_get_max(struct snd_pcm_hw_params *p, int n) +{ + if (param_is_interval(n)) { + struct snd_interval *i = param_to_interval(p, n); + return i->max; + } + return 0; +} + +static void param_set_int(struct snd_pcm_hw_params *p, int n, unsigned int val) +{ + if (param_is_interval(n)) { + struct snd_interval *i = param_to_interval(p, n); + i->min = val; + i->max = val; + i->integer = 1; + } +} + +static unsigned int param_get_int(struct snd_pcm_hw_params *p, int n) +{ + if (param_is_interval(n)) { + struct snd_interval *i = param_to_interval(p, n); + if (i->integer) + return i->max; + } + return 0; +} + +static void param_init(struct snd_pcm_hw_params *p) +{ + int n; + + memset(p, 0, sizeof(*p)); + for (n = SNDRV_PCM_HW_PARAM_FIRST_MASK; + n <= SNDRV_PCM_HW_PARAM_LAST_MASK; n++) { + struct snd_mask *m = param_to_mask(p, n); + m->bits[0] = ~0; + m->bits[1] = ~0; + } + for (n = SNDRV_PCM_HW_PARAM_FIRST_INTERVAL; + n <= SNDRV_PCM_HW_PARAM_LAST_INTERVAL; n++) { + struct snd_interval *i = param_to_interval(p, n); + i->min = 0; + i->max = ~0; + } + p->rmask = ~0U; + p->cmask = 0; + p->info = ~0U; +} + +#define PCM_ERROR_MAX 128 + +struct pcm { + int fd; + unsigned int flags; + int running:1; + int prepared:1; + int underruns; + unsigned int buffer_size; + unsigned int boundary; + char error[PCM_ERROR_MAX]; + struct pcm_config config; + struct snd_pcm_mmap_status *mmap_status; + struct snd_pcm_mmap_control *mmap_control; + struct snd_pcm_sync_ptr *sync_ptr; + void *mmap_buffer; + unsigned int noirq_frames_per_msec; + long pcm_delay; + unsigned int subdevice; +}; + +unsigned int pcm_get_buffer_size(struct pcm *pcm) +{ + return pcm->buffer_size; +} + +int pcm_get_file_descriptor(struct pcm *pcm) +{ + return pcm->fd; +} + +const char* pcm_get_error(struct pcm *pcm) +{ + return pcm->error; +} + +unsigned int pcm_get_subdevice(struct pcm *pcm) +{ + return pcm->subdevice; +} + +static int oops(struct pcm *pcm, int e, const char *fmt, ...) +{ + va_list ap; + int sz; + + va_start(ap, fmt); + vsnprintf(pcm->error, PCM_ERROR_MAX, fmt, ap); + va_end(ap); + sz = strlen(pcm->error); + + if (errno) + snprintf(pcm->error + sz, PCM_ERROR_MAX - sz, + ": %s", strerror(e)); + return -1; +} + +static unsigned int pcm_format_to_alsa(enum pcm_format format) +{ + switch (format) { + + case PCM_FORMAT_S8: + return SNDRV_PCM_FORMAT_S8; + + default: + case PCM_FORMAT_S16_LE: + return SNDRV_PCM_FORMAT_S16_LE; + case PCM_FORMAT_S16_BE: + return SNDRV_PCM_FORMAT_S16_BE; + + case PCM_FORMAT_S24_LE: + return SNDRV_PCM_FORMAT_S24_LE; + case PCM_FORMAT_S24_BE: + return SNDRV_PCM_FORMAT_S24_BE; + + case PCM_FORMAT_S24_3LE: + return SNDRV_PCM_FORMAT_S24_3LE; + case PCM_FORMAT_S24_3BE: + return SNDRV_PCM_FORMAT_S24_3BE; + + case PCM_FORMAT_S32_LE: + return SNDRV_PCM_FORMAT_S32_LE; + case PCM_FORMAT_S32_BE: + return SNDRV_PCM_FORMAT_S32_BE; + }; +} + +unsigned int pcm_format_to_bits(enum pcm_format format) +{ + switch (format) { + case PCM_FORMAT_S32_LE: + case PCM_FORMAT_S32_BE: + case PCM_FORMAT_S24_LE: + case PCM_FORMAT_S24_BE: + return 32; + case PCM_FORMAT_S24_3LE: + case PCM_FORMAT_S24_3BE: + return 24; + default: + case PCM_FORMAT_S16_LE: + case PCM_FORMAT_S16_BE: + return 16; + case PCM_FORMAT_S8: + return 8; + }; +} + +unsigned int pcm_bytes_to_frames(struct pcm *pcm, unsigned int bytes) +{ + return bytes / (pcm->config.channels * + (pcm_format_to_bits(pcm->config.format) >> 3)); +} + +unsigned int pcm_frames_to_bytes(struct pcm *pcm, unsigned int frames) +{ + return frames * pcm->config.channels * + (pcm_format_to_bits(pcm->config.format) >> 3); +} + +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) + return -1; + } + return 0; +} + +static int pcm_hw_mmap_status(struct pcm *pcm) +{ + if (pcm->sync_ptr) + return 0; + + int page_size = sysconf(_SC_PAGE_SIZE); + pcm->mmap_status = mmap(NULL, page_size, PROT_READ, MAP_FILE | MAP_SHARED, + pcm->fd, SNDRV_PCM_MMAP_OFFSET_STATUS); + if (pcm->mmap_status == MAP_FAILED) + pcm->mmap_status = NULL; + if (!pcm->mmap_status) + goto mmap_error; + + pcm->mmap_control = mmap(NULL, page_size, PROT_READ | PROT_WRITE, + MAP_FILE | MAP_SHARED, pcm->fd, SNDRV_PCM_MMAP_OFFSET_CONTROL); + if (pcm->mmap_control == MAP_FAILED) + pcm->mmap_control = NULL; + if (!pcm->mmap_control) { + munmap(pcm->mmap_status, page_size); + pcm->mmap_status = NULL; + goto mmap_error; + } + pcm->mmap_control->avail_min = 1; + + return 0; + +mmap_error: + + pcm->sync_ptr = calloc(1, sizeof(*pcm->sync_ptr)); + if (!pcm->sync_ptr) + return -ENOMEM; + pcm->mmap_status = &pcm->sync_ptr->s.status; + pcm->mmap_control = &pcm->sync_ptr->c.control; + pcm->mmap_control->avail_min = 1; + pcm_sync_ptr(pcm, 0); + + return 0; +} + +static void pcm_hw_munmap_status(struct pcm *pcm) { + if (pcm->sync_ptr) { + free(pcm->sync_ptr); + pcm->sync_ptr = NULL; + } else { + int page_size = sysconf(_SC_PAGE_SIZE); + if (pcm->mmap_status) + munmap(pcm->mmap_status, page_size); + if (pcm->mmap_control) + munmap(pcm->mmap_control, page_size); + } + pcm->mmap_status = NULL; + pcm->mmap_control = NULL; +} + +static int pcm_areas_copy(struct pcm *pcm, unsigned int pcm_offset, + char *buf, unsigned int src_offset, + unsigned int frames) +{ + int size_bytes = pcm_frames_to_bytes(pcm, frames); + int pcm_offset_bytes = pcm_frames_to_bytes(pcm, pcm_offset); + int src_offset_bytes = pcm_frames_to_bytes(pcm, src_offset); + + /* interleaved only atm */ + if (pcm->flags & PCM_IN) + memcpy(buf + src_offset_bytes, + (char*)pcm->mmap_buffer + pcm_offset_bytes, + size_bytes); + else + memcpy((char*)pcm->mmap_buffer + pcm_offset_bytes, + buf + src_offset_bytes, + size_bytes); + return 0; +} + +static int pcm_mmap_transfer_areas(struct pcm *pcm, char *buf, + unsigned int offset, unsigned int size) +{ + void *pcm_areas; + int commit; + unsigned int pcm_offset, frames, count = 0; + + while (size > 0) { + frames = size; + pcm_mmap_begin(pcm, &pcm_areas, &pcm_offset, &frames); + pcm_areas_copy(pcm, pcm_offset, buf, offset, frames); + commit = pcm_mmap_commit(pcm, pcm_offset, frames); + if (commit < 0) { + oops(pcm, commit, "failed to commit %d frames\n", frames); + return commit; + } + + offset += commit; + count += commit; + size -= commit; + } + return count; +} + +int pcm_get_htimestamp(struct pcm *pcm, unsigned int *avail, + struct timespec *tstamp) +{ + int frames; + int rc; + snd_pcm_uframes_t hw_ptr; + + if (!pcm_is_ready(pcm)) + return -1; + + rc = pcm_sync_ptr(pcm, SNDRV_PCM_SYNC_PTR_APPL|SNDRV_PCM_SYNC_PTR_HWSYNC); + if (rc < 0) + return -1; + + if ((pcm->mmap_status->state != PCM_STATE_RUNNING) && + (pcm->mmap_status->state != PCM_STATE_DRAINING)) + return -1; + + *tstamp = pcm->mmap_status->tstamp; + if (tstamp->tv_sec == 0 && tstamp->tv_nsec == 0) + return -1; + + hw_ptr = pcm->mmap_status->hw_ptr; + if (pcm->flags & PCM_IN) + frames = hw_ptr - pcm->mmap_control->appl_ptr; + else + frames = hw_ptr + pcm->buffer_size - pcm->mmap_control->appl_ptr; + + if (frames < 0) + return -1; + + *avail = (unsigned int)frames; + + return 0; +} + +int pcm_write(struct pcm *pcm, const void *data, unsigned int count) +{ + struct snd_xferi x; + + if (pcm->flags & PCM_IN) + return -EINVAL; + + x.buf = (void*)data; + x.frames = count / (pcm->config.channels * + pcm_format_to_bits(pcm->config.format) / 8); + + for (;;) { + if (!pcm->running) { + int prepare_error = pcm_prepare(pcm); + if (prepare_error) + return prepare_error; + if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_WRITEI_FRAMES, &x)) + return oops(pcm, errno, "cannot write initial data"); + pcm->running = 1; + return 0; + } + if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_WRITEI_FRAMES, &x)) { + pcm->prepared = 0; + pcm->running = 0; + if (errno == EPIPE) { + /* we failed to make our window -- try to restart if we are + * allowed to do so. Otherwise, simply allow the EPIPE error to + * propagate up to the app level */ + pcm->underruns++; + if (pcm->flags & PCM_NORESTART) + return -EPIPE; + continue; + } + return oops(pcm, errno, "cannot write stream data"); + } + return 0; + } +} + +int pcm_read(struct pcm *pcm, void *data, unsigned int count) +{ + struct snd_xferi x; + + if (!(pcm->flags & PCM_IN)) + return -EINVAL; + + x.buf = data; + x.frames = count / (pcm->config.channels * + pcm_format_to_bits(pcm->config.format) / 8); + + for (;;) { + if (!pcm->running) { + if (pcm_start(pcm) < 0) { + fprintf(stderr, "start error"); + return -errno; + } + } + if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_READI_FRAMES, &x)) { + pcm->prepared = 0; + pcm->running = 0; + if (errno == EPIPE) { + /* we failed to make our window -- try to restart */ + pcm->underruns++; + continue; + } + return oops(pcm, errno, "cannot read stream data"); + } + return 0; + } +} + +static struct pcm bad_pcm = { + .fd = -1, +}; + +struct pcm_params *pcm_params_get(unsigned int card, unsigned int device, + unsigned int flags) +{ + struct snd_pcm_hw_params *params; + char fn[256]; + int fd; + + snprintf(fn, sizeof(fn), "/dev/snd/pcmC%uD%u%c", card, device, + flags & PCM_IN ? 'c' : 'p'); + + fd = open(fn, O_RDWR); + if (fd < 0) { + fprintf(stderr, "cannot open device '%s'\n", fn); + goto err_open; + } + + params = calloc(1, sizeof(struct snd_pcm_hw_params)); + if (!params) + goto err_calloc; + + param_init(params); + if (ioctl(fd, SNDRV_PCM_IOCTL_HW_REFINE, params)) { + fprintf(stderr, "SNDRV_PCM_IOCTL_HW_REFINE error (%d)\n", errno); + goto err_hw_refine; + } + + close(fd); + + return (struct pcm_params *)params; + +err_hw_refine: + free(params); +err_calloc: + close(fd); +err_open: + return NULL; +} + +void pcm_params_free(struct pcm_params *pcm_params) +{ + struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params; + + if (params) + free(params); +} + +static int pcm_param_to_alsa(enum pcm_param param) +{ + switch (param) { + case PCM_PARAM_ACCESS: + return SNDRV_PCM_HW_PARAM_ACCESS; + case PCM_PARAM_FORMAT: + return SNDRV_PCM_HW_PARAM_FORMAT; + case PCM_PARAM_SUBFORMAT: + return SNDRV_PCM_HW_PARAM_SUBFORMAT; + case PCM_PARAM_SAMPLE_BITS: + return SNDRV_PCM_HW_PARAM_SAMPLE_BITS; + break; + case PCM_PARAM_FRAME_BITS: + return SNDRV_PCM_HW_PARAM_FRAME_BITS; + break; + case PCM_PARAM_CHANNELS: + return SNDRV_PCM_HW_PARAM_CHANNELS; + break; + case PCM_PARAM_RATE: + return SNDRV_PCM_HW_PARAM_RATE; + break; + case PCM_PARAM_PERIOD_TIME: + return SNDRV_PCM_HW_PARAM_PERIOD_TIME; + break; + case PCM_PARAM_PERIOD_SIZE: + return SNDRV_PCM_HW_PARAM_PERIOD_SIZE; + break; + case PCM_PARAM_PERIOD_BYTES: + return SNDRV_PCM_HW_PARAM_PERIOD_BYTES; + break; + case PCM_PARAM_PERIODS: + return SNDRV_PCM_HW_PARAM_PERIODS; + break; + case PCM_PARAM_BUFFER_TIME: + return SNDRV_PCM_HW_PARAM_BUFFER_TIME; + break; + case PCM_PARAM_BUFFER_SIZE: + return SNDRV_PCM_HW_PARAM_BUFFER_SIZE; + break; + case PCM_PARAM_BUFFER_BYTES: + return SNDRV_PCM_HW_PARAM_BUFFER_BYTES; + break; + case PCM_PARAM_TICK_TIME: + return SNDRV_PCM_HW_PARAM_TICK_TIME; + break; + + default: + return -1; + } +} + +struct pcm_mask *pcm_params_get_mask(struct pcm_params *pcm_params, + enum pcm_param param) +{ + int p; + struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params; + if (params == NULL) { + return NULL; + } + + p = pcm_param_to_alsa(param); + if (p < 0 || !param_is_mask(p)) { + return NULL; + } + + return (struct pcm_mask *)param_to_mask(params, p); +} + +unsigned int pcm_params_get_min(struct pcm_params *pcm_params, + enum pcm_param param) +{ + struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params; + int p; + + if (!params) + return 0; + + p = pcm_param_to_alsa(param); + if (p < 0) + return 0; + + return param_get_min(params, p); +} + +unsigned int pcm_params_get_max(struct pcm_params *pcm_params, + enum pcm_param param) +{ + struct snd_pcm_hw_params *params = (struct snd_pcm_hw_params *)pcm_params; + int p; + + if (!params) + return 0; + + p = pcm_param_to_alsa(param); + if (p < 0) + return 0; + + return param_get_max(params, p); +} + +int pcm_close(struct pcm *pcm) +{ + if (pcm == &bad_pcm) + return 0; + + pcm_hw_munmap_status(pcm); + + if (pcm->flags & PCM_MMAP) { + pcm_stop(pcm); + munmap(pcm->mmap_buffer, pcm_frames_to_bytes(pcm, pcm->buffer_size)); + } + + if (pcm->fd >= 0) + close(pcm->fd); + pcm->prepared = 0; + pcm->running = 0; + pcm->buffer_size = 0; + pcm->fd = -1; + free(pcm); + return 0; +} + +struct pcm *pcm_open(unsigned int card, unsigned int device, + unsigned int flags, struct pcm_config *config) +{ + struct pcm *pcm; + struct snd_pcm_info info; + struct snd_pcm_hw_params params; + struct snd_pcm_sw_params sparams; + char fn[256]; + int rc; + + pcm = calloc(1, sizeof(struct pcm)); + if (!pcm || !config) + return &bad_pcm; /* TODO: could support default config here */ + + pcm->config = *config; + + snprintf(fn, sizeof(fn), "/dev/snd/pcmC%uD%u%c", card, device, + flags & PCM_IN ? 'c' : 'p'); + + pcm->flags = flags; + pcm->fd = open(fn, O_RDWR); + if (pcm->fd < 0) { + oops(pcm, errno, "cannot open device '%s'", fn); + return pcm; + } + + if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_INFO, &info)) { + oops(pcm, errno, "cannot get info"); + goto fail_close; + } + pcm->subdevice = info.subdevice; + + param_init(¶ms); + param_set_mask(¶ms, SNDRV_PCM_HW_PARAM_FORMAT, + pcm_format_to_alsa(config->format)); + param_set_mask(¶ms, SNDRV_PCM_HW_PARAM_SUBFORMAT, + SNDRV_PCM_SUBFORMAT_STD); + param_set_min(¶ms, SNDRV_PCM_HW_PARAM_PERIOD_SIZE, config->period_size); + param_set_int(¶ms, SNDRV_PCM_HW_PARAM_SAMPLE_BITS, + pcm_format_to_bits(config->format)); + param_set_int(¶ms, SNDRV_PCM_HW_PARAM_FRAME_BITS, + pcm_format_to_bits(config->format) * config->channels); + param_set_int(¶ms, SNDRV_PCM_HW_PARAM_CHANNELS, + config->channels); + param_set_int(¶ms, SNDRV_PCM_HW_PARAM_PERIODS, config->period_count); + param_set_int(¶ms, SNDRV_PCM_HW_PARAM_RATE, config->rate); + + if (flags & PCM_NOIRQ) { + + if (!(flags & PCM_MMAP)) { + oops(pcm, -EINVAL, "noirq only currently supported with mmap()."); + goto fail; + } + + params.flags |= SNDRV_PCM_HW_PARAMS_NO_PERIOD_WAKEUP; + pcm->noirq_frames_per_msec = config->rate / 1000; + } + + if (flags & PCM_MMAP) + param_set_mask(¶ms, SNDRV_PCM_HW_PARAM_ACCESS, + SNDRV_PCM_ACCESS_MMAP_INTERLEAVED); + else + param_set_mask(¶ms, SNDRV_PCM_HW_PARAM_ACCESS, + SNDRV_PCM_ACCESS_RW_INTERLEAVED); + + if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_HW_PARAMS, ¶ms)) { + oops(pcm, errno, "cannot set hw params"); + goto fail_close; + } + + /* get our refined hw_params */ + config->period_size = param_get_int(¶ms, SNDRV_PCM_HW_PARAM_PERIOD_SIZE); + config->period_count = param_get_int(¶ms, SNDRV_PCM_HW_PARAM_PERIODS); + pcm->buffer_size = config->period_count * config->period_size; + + if (flags & PCM_MMAP) { + pcm->mmap_buffer = mmap(NULL, pcm_frames_to_bytes(pcm, pcm->buffer_size), + PROT_READ | PROT_WRITE, MAP_FILE | MAP_SHARED, pcm->fd, 0); + if (pcm->mmap_buffer == MAP_FAILED) { + oops(pcm, -errno, "failed to mmap buffer %d bytes\n", + pcm_frames_to_bytes(pcm, pcm->buffer_size)); + goto fail_close; + } + } + + + memset(&sparams, 0, sizeof(sparams)); + sparams.tstamp_mode = SNDRV_PCM_TSTAMP_ENABLE; + sparams.period_step = 1; + sparams.avail_min = 1; + + if (!config->start_threshold) { + if (pcm->flags & PCM_IN) + pcm->config.start_threshold = sparams.start_threshold = 1; + else + pcm->config.start_threshold = sparams.start_threshold = + config->period_count * config->period_size / 2; + } else + sparams.start_threshold = config->start_threshold; + + /* pick a high stop threshold - todo: does this need further tuning */ + if (!config->stop_threshold) { + if (pcm->flags & PCM_IN) + pcm->config.stop_threshold = sparams.stop_threshold = + config->period_count * config->period_size * 10; + else + pcm->config.stop_threshold = sparams.stop_threshold = + config->period_count * config->period_size; + } + else + sparams.stop_threshold = config->stop_threshold; + + sparams.xfer_align = config->period_size / 2; /* needed for old kernels */ + sparams.silence_size = 0; + sparams.silence_threshold = config->silence_threshold; + pcm->boundary = sparams.boundary = pcm->buffer_size; + + while (pcm->boundary * 2 <= INT_MAX - pcm->buffer_size) + pcm->boundary *= 2; + + if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_SW_PARAMS, &sparams)) { + oops(pcm, errno, "cannot set sw params"); + goto fail; + } + + rc = pcm_hw_mmap_status(pcm); + if (rc < 0) { + oops(pcm, rc, "mmap status failed"); + goto fail; + } + +#ifdef SNDRV_PCM_IOCTL_TTSTAMP + if (pcm->flags & PCM_MONOTONIC) { + int arg = SNDRV_PCM_TSTAMP_TYPE_MONOTONIC; + rc = ioctl(pcm->fd, SNDRV_PCM_IOCTL_TTSTAMP, &arg); + if (rc < 0) { + oops(pcm, rc, "cannot set timestamp type"); + goto fail; + } + } +#endif + + pcm->underruns = 0; + return pcm; + +fail: + if (flags & PCM_MMAP) + munmap(pcm->mmap_buffer, pcm_frames_to_bytes(pcm, pcm->buffer_size)); +fail_close: + close(pcm->fd); + pcm->fd = -1; + return pcm; +} + +int pcm_is_ready(struct pcm *pcm) +{ + return pcm->fd >= 0; +} + +int pcm_prepare(struct pcm *pcm) +{ + if (pcm->prepared) + return 0; + + if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_PREPARE) < 0) + return oops(pcm, errno, "cannot prepare channel"); + + pcm->prepared = 1; + return 0; +} + +int pcm_start(struct pcm *pcm) +{ + int prepare_error = pcm_prepare(pcm); + if (prepare_error) + return prepare_error; + + if (pcm->flags & PCM_MMAP) + pcm_sync_ptr(pcm, 0); + + if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_START) < 0) + return oops(pcm, errno, "cannot start channel"); + + pcm->running = 1; + return 0; +} + +int pcm_stop(struct pcm *pcm) +{ + if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_DROP) < 0) + return oops(pcm, errno, "cannot stop channel"); + + pcm->prepared = 0; + pcm->running = 0; + return 0; +} + +static inline int pcm_mmap_playback_avail(struct pcm *pcm) +{ + int avail; + + avail = pcm->mmap_status->hw_ptr + pcm->buffer_size - pcm->mmap_control->appl_ptr; + + if (avail < 0) + avail += pcm->boundary; + else if (avail >= (int)pcm->boundary) + avail -= pcm->boundary; + + return avail; +} + +static inline int pcm_mmap_capture_avail(struct pcm *pcm) +{ + int avail = pcm->mmap_status->hw_ptr - pcm->mmap_control->appl_ptr; + if (avail < 0) + avail += pcm->boundary; + return avail; +} + +static inline int pcm_mmap_avail(struct pcm *pcm) +{ + pcm_sync_ptr(pcm, SNDRV_PCM_SYNC_PTR_HWSYNC); + if (pcm->flags & PCM_IN) + return pcm_mmap_capture_avail(pcm); + else + return pcm_mmap_playback_avail(pcm); +} + +static void pcm_mmap_appl_forward(struct pcm *pcm, int frames) +{ + unsigned int appl_ptr = pcm->mmap_control->appl_ptr; + appl_ptr += frames; + + /* check for boundary wrap */ + if (appl_ptr > pcm->boundary) + appl_ptr -= pcm->boundary; + pcm->mmap_control->appl_ptr = appl_ptr; +} + +int pcm_mmap_begin(struct pcm *pcm, void **areas, unsigned int *offset, + unsigned int *frames) +{ + unsigned int continuous, copy_frames, avail; + + /* return the mmap buffer */ + *areas = pcm->mmap_buffer; + + /* and the application offset in frames */ + *offset = pcm->mmap_control->appl_ptr % pcm->buffer_size; + + avail = pcm_mmap_avail(pcm); + if (avail > pcm->buffer_size) + avail = pcm->buffer_size; + continuous = pcm->buffer_size - *offset; + + /* we can only copy frames if the are availabale and continuos */ + copy_frames = *frames; + if (copy_frames > avail) + copy_frames = avail; + if (copy_frames > continuous) + copy_frames = continuous; + *frames = copy_frames; + + return 0; +} + +int pcm_mmap_commit(struct pcm *pcm, unsigned int offset, unsigned int frames) +{ + /* not used */ + (void) offset; + + /* update the application pointer in userspace and kernel */ + pcm_mmap_appl_forward(pcm, frames); + pcm_sync_ptr(pcm, 0); + + return frames; +} + +int pcm_avail_update(struct pcm *pcm) +{ + pcm_sync_ptr(pcm, 0); + return pcm_mmap_avail(pcm); +} + +int pcm_state(struct pcm *pcm) +{ + int err = pcm_sync_ptr(pcm, 0); + if (err < 0) + return err; + + return pcm->mmap_status->state; +} + +int pcm_wait(struct pcm *pcm, int timeout) +{ + struct pollfd pfd; + int err; + + pfd.fd = pcm->fd; + pfd.events = POLLIN | POLLOUT | POLLERR | POLLNVAL; + + do { + /* let's wait for avail or timeout */ + err = poll(&pfd, 1, timeout); + if (err < 0) + return -errno; + + /* timeout ? */ + if (err == 0) + return 0; + + /* have we been interrupted ? */ + if (errno == -EINTR) + continue; + + /* check for any errors */ + if (pfd.revents & (POLLERR | POLLNVAL)) { + switch (pcm_state(pcm)) { + case PCM_STATE_XRUN: + return -EPIPE; + case PCM_STATE_SUSPENDED: + return -ESTRPIPE; + case PCM_STATE_DISCONNECTED: + return -ENODEV; + default: + return -EIO; + } + } + /* poll again if fd not ready for IO */ + } while (!(pfd.revents & (POLLIN | POLLOUT))); + + return 1; +} + +int pcm_mmap_transfer(struct pcm *pcm, const void *buffer, unsigned int bytes) +{ + int err = 0, frames, avail; + unsigned int offset = 0, count; + + if (bytes == 0) + return 0; + + count = pcm_bytes_to_frames(pcm, bytes); + + while (count > 0) { + + /* get the available space for writing new frames */ + avail = pcm_avail_update(pcm); + if (avail < 0) { + fprintf(stderr, "cannot determine available mmap frames"); + return err; + } + + /* start the audio if we reach the threshold */ + if (!pcm->running && + (pcm->buffer_size - avail) >= pcm->config.start_threshold) { + if (pcm_start(pcm) < 0) { + fprintf(stderr, "start error: hw 0x%x app 0x%x avail 0x%x\n", + (unsigned int)pcm->mmap_status->hw_ptr, + (unsigned int)pcm->mmap_control->appl_ptr, + avail); + return -errno; + } + } + + /* sleep until we have space to write new frames */ + if (pcm->running && + (unsigned int)avail < pcm->mmap_control->avail_min) { + int time = -1; + + if (pcm->flags & PCM_NOIRQ) + time = (pcm->buffer_size - avail - pcm->mmap_control->avail_min) + / pcm->noirq_frames_per_msec; + + err = pcm_wait(pcm, time); + if (err < 0) { + pcm->prepared = 0; + pcm->running = 0; + fprintf(stderr, "wait error: hw 0x%x app 0x%x avail 0x%x\n", + (unsigned int)pcm->mmap_status->hw_ptr, + (unsigned int)pcm->mmap_control->appl_ptr, + avail); + pcm->mmap_control->appl_ptr = 0; + return err; + } + continue; + } + + frames = count; + if (frames > avail) + frames = avail; + + if (!frames) + break; + + /* copy frames from buffer */ + frames = pcm_mmap_transfer_areas(pcm, (void *)buffer, offset, frames); + if (frames < 0) { + fprintf(stderr, "write error: hw 0x%x app 0x%x avail 0x%x\n", + (unsigned int)pcm->mmap_status->hw_ptr, + (unsigned int)pcm->mmap_control->appl_ptr, + avail); + return frames; + } + + offset += frames; + count -= frames; + } + + return 0; +} + +int pcm_mmap_write(struct pcm *pcm, const void *data, unsigned int count) +{ + if ((~pcm->flags) & (PCM_OUT | PCM_MMAP)) + return -ENOSYS; + + return pcm_mmap_transfer(pcm, (void *)data, count); +} + +int pcm_mmap_read(struct pcm *pcm, void *data, unsigned int count) +{ + if ((~pcm->flags) & (PCM_IN | PCM_MMAP)) + return -ENOSYS; + + return pcm_mmap_transfer(pcm, data, count); +} + +long pcm_get_delay(struct pcm *pcm) +{ + if (ioctl(pcm->fd, SNDRV_PCM_IOCTL_DELAY, &pcm->pcm_delay) < 0) + return -1; + + return pcm->pcm_delay; +} |