/* * ALSA server * Copyright (c) by Abramo Bagnara * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation; either version 2 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include "asoundlib.h" #include "pcm_local.h" #include "aserver.h" #include "list.h" char *command; #if __GNUC__ > 2 || (__GNUC__ == 2 && __GNUC_MINOR__ >= 95) #define error(...) do {\ fprintf(stderr, "%s: %s:%d: ", command, __FUNCTION__, __LINE__); \ fprintf(stderr, __VA_ARGS__); \ putc('\n', stderr); \ } while (0) #else #define error(args...) do {\ fprintf(stderr, "%s: %s:%d: ", command, __FUNCTION__, __LINE__); \ fprintf(stderr, ##args); \ putc('\n', stderr); \ } while (0) #endif #define perrno(string) error("%s", strerror(errno)) int make_local_socket(const char *filename) { size_t l = strlen(filename); size_t size = offsetof(struct sockaddr_un, sun_path) + l; struct sockaddr_un *addr = alloca(size); int sock; sock = socket(PF_LOCAL, SOCK_STREAM, 0); if (sock < 0) { int result = -errno; perrno("socket"); return result; } unlink(filename); addr->sun_family = AF_LOCAL; memcpy(addr->sun_path, filename, l); if (bind(sock, (struct sockaddr *) addr, size) < 0) { int result = -errno; perrno("bind"); return result; } return sock; } int make_inet_socket(int port) { struct sockaddr_in addr; int sock; sock = socket(PF_INET, SOCK_STREAM, 0); if (sock < 0) { int result = -errno; perrno("socket"); return result; } addr.sin_family = AF_INET; addr.sin_port = htons(port); addr.sin_addr.s_addr = INADDR_ANY; if (bind(sock, (struct sockaddr *) &addr, sizeof(addr)) < 0) { int result = -errno; perrno("bind"); return result; } return sock; } int send_fd(int socket, void *data, size_t len, int fd) { int ret; size_t cmsg_len = CMSG_LEN(sizeof(int)); struct cmsghdr *cmsg = alloca(cmsg_len); int *fds = (int *) CMSG_DATA(cmsg); struct msghdr msghdr; struct iovec vec; vec.iov_base = (void *)&data; vec.iov_len = len; cmsg->cmsg_len = cmsg_len; cmsg->cmsg_level = SOL_SOCKET; cmsg->cmsg_type = SCM_RIGHTS; *fds = fd; msghdr.msg_name = NULL; msghdr.msg_namelen = 0; msghdr.msg_iov = &vec; msghdr.msg_iovlen = 1; msghdr.msg_control = cmsg; msghdr.msg_controllen = cmsg_len; msghdr.msg_flags = 0; ret = sendmsg(socket, &msghdr, 0 ); if (ret < 0) { perrno("sendmsg"); return -errno; } return ret; } struct pollfd pollfds[OPEN_MAX]; unsigned int pollfds_count = 0; typedef struct waiter waiter_t; typedef int (*waiter_handler_t)(waiter_t *waiter, unsigned short events); struct waiter { int fd; void *private_data; waiter_handler_t handler; }; waiter_t waiters[OPEN_MAX]; void add_waiter(int fd, unsigned short events, waiter_handler_t handler, void *data) { waiter_t *w = &waiters[fd]; struct pollfd *pfd = &pollfds[pollfds_count]; assert(!w->handler); pfd->fd = fd; pfd->events = events; pfd->revents = 0; w->fd = fd; w->private_data = data; w->handler = handler; pollfds_count++; } void del_waiter(int fd) { waiter_t *w = &waiters[fd]; unsigned int k; assert(w->handler); w->handler = 0; for (k = 0; k < pollfds_count; ++k) { if (pollfds[k].fd == fd) break; } assert(k < pollfds_count); pollfds_count--; memmove(&pollfds[k], &pollfds[k + 1], pollfds_count - k); } typedef struct { struct list_head list; int fd; int local; } master_t; LIST_HEAD(masters); typedef struct client client_t; typedef struct { int (*open)(client_t *client, int *cookie); int (*cmd)(client_t *client); int (*close)(client_t *client); } transport_ops_t; struct client { struct list_head list; struct socket { int fd; int local; } data, ctrl; int transport_type; int dev_type; char name[256]; int stream; int mode; transport_ops_t *ops; union { struct { snd_pcm_t *handle; int fd; } pcm; struct { snd_ctl_t *handle; int fd; } control; #if 0 struct { snd_rawmidi_t *handle; } rawmidi; struct { snd_timer_open_t *handle; } timer; struct { snd_hwdep_t *handle; } hwdep; struct { snd_seq_t *handle; } seq; #endif } device; int polling; int open; int cookie; union { struct { int ctrl_id; void *ctrl; } shm; } transport; }; LIST_HEAD(clients); typedef struct { struct list_head list; int fd; uint32_t cookie; int local; } pending_t; LIST_HEAD(pendings); int pcm_handler(waiter_t *waiter, unsigned short events) { client_t *client = waiter->private_data; char buf[1]; ssize_t n; if (events & POLLIN) { n = write(client->data.fd, buf, 1); if (n != 1) { perrno("write"); return -errno; } } else if (events & POLLOUT) { n = read(client->data.fd, buf, 1); if (n != 1) { perrno("read"); return -errno; } } del_waiter(waiter->fd); client->polling = 0; return 0; } int pcm_shm_open(client_t *client, int *cookie) { int shmid; snd_pcm_t *pcm; int err; int result; err = snd_pcm_open(&pcm, client->name, client->stream, client->mode); if (err < 0) return err; client->device.pcm.handle = pcm; client->device.pcm.fd = snd_pcm_poll_descriptor(pcm); shmid = shmget(IPC_PRIVATE, PCM_SHM_SIZE, 0666); if (shmid < 0) { result = -errno; perrno("shmget"); goto _err; } client->transport.shm.ctrl_id = shmid; client->transport.shm.ctrl = shmat(shmid, 0, 0); if (!client->transport.shm.ctrl) { result = -errno; shmctl(shmid, IPC_RMID, 0); perrno("shmat"); goto _err; } *cookie = shmid; return 0; _err: snd_pcm_close(pcm); return result; } int pcm_shm_close(client_t *client) { int err; snd_pcm_client_shm_t *ctrl = client->transport.shm.ctrl; if (client->polling) { del_waiter(client->device.pcm.fd); client->polling = 0; } /* FIXME: blocking */ err = snd_pcm_close(client->device.pcm.handle); ctrl->result = err; if (err < 0) perrno("snd_pcm_close"); if (client->transport.shm.ctrl) { err = shmdt((void *)client->transport.shm.ctrl); if (err < 0) perrno("shmdt"); err = shmctl(client->transport.shm.ctrl_id, IPC_RMID, 0); if (err < 0) perrno("shmctl"); client->transport.shm.ctrl = 0; } client->open = 0; return 0; } int pcm_shm_cmd(client_t *client) { snd_pcm_client_shm_t *ctrl = client->transport.shm.ctrl; struct pollfd pfd; char buf[1]; int err; int cmd; snd_pcm_t *pcm; err = read(client->ctrl.fd, buf, 1); if (err != 1) return -EBADFD; cmd = ctrl->cmd; ctrl->cmd = 0; pcm = client->device.pcm.handle; switch (cmd) { case SND_PCM_IOCTL_INFO: ctrl->result = snd_pcm_info(pcm, &ctrl->u.info); break; case SND_PCM_IOCTL_PARAMS: ctrl->result = snd_pcm_params(pcm, &ctrl->u.params); break; case SND_PCM_IOCTL_PARAMS_INFO: ctrl->result = snd_pcm_params_info(pcm, &ctrl->u.params_info); break; case SND_PCM_IOCTL_SETUP: ctrl->result = snd_pcm_setup(pcm, &ctrl->u.setup); break; case SND_PCM_IOCTL_STATUS: ctrl->result = snd_pcm_status(pcm, &ctrl->u.status); break; case SND_PCM_IOCTL_STATE: ctrl->result = snd_pcm_state(pcm); break; case SND_PCM_IOCTL_DELAY: ctrl->result = snd_pcm_delay(pcm, &ctrl->u.delay); break; case SND_PCM_IOCTL_AVAIL_UPDATE: ctrl->result = snd_pcm_avail_update(pcm); break; case SND_PCM_IOCTL_PREPARE: ctrl->result = snd_pcm_prepare(pcm); break; case SND_PCM_IOCTL_START: ctrl->result = snd_pcm_start(pcm); break; case SND_PCM_IOCTL_DRAIN: ctrl->result = snd_pcm_drain(pcm); break; case SND_PCM_IOCTL_DROP: ctrl->result = snd_pcm_drop(pcm); break; case SND_PCM_IOCTL_PAUSE: ctrl->result = snd_pcm_pause(pcm, ctrl->u.pause); break; case SND_PCM_IOCTL_CHANNEL_INFO: ctrl->result = snd_pcm_channel_info(pcm, &ctrl->u.channel_info); break; case SND_PCM_IOCTL_CHANNEL_PARAMS: ctrl->result = snd_pcm_channel_params(pcm, &ctrl->u.channel_params); break; case SND_PCM_IOCTL_CHANNEL_SETUP: ctrl->result = snd_pcm_channel_setup(pcm, &ctrl->u.channel_setup); break; case SND_PCM_IOCTL_REWIND: ctrl->result = snd_pcm_rewind(pcm, ctrl->u.rewind); break; case SND_PCM_IOCTL_LINK: { struct list_head *item; list_for_each(item, &clients) { client_t *client = list_entry(item, client_t, list); if (!client->open) continue; if (client->data.fd == ctrl->u.link) { ctrl->result = snd_pcm_link(pcm, client->device.pcm.handle); break; } } ctrl->result = -EBADFD; break; } case SND_PCM_IOCTL_UNLINK: ctrl->result = snd_pcm_unlink(pcm); break; case SND_PCM_IOCTL_MMAP_DATA: case SND_PCM_IOCTL_MMAP_CONTROL: case SND_PCM_IOCTL_MMAP_STATUS: { pfd.fd = client->ctrl.fd; pfd.events = POLLHUP; if (poll(&pfd, 1, 0) == 1) return -EBADFD; err = send_fd(client->ctrl.fd, buf, 1, client->device.pcm.fd); if (err != 1) return -EBADFD; ctrl->result = 0; return 0; } case SND_PCM_IOCTL_MUNMAP_DATA: case SND_PCM_IOCTL_MUNMAP_CONTROL: case SND_PCM_IOCTL_MUNMAP_STATUS: ctrl->result = 0; break; case SND_PCM_IOCTL_MMAP_FORWARD: ctrl->result = snd_pcm_mmap_forward(pcm, ctrl->u.mmap_forward); break; case SND_PCM_IOCTL_CLOSE: client->ops->close(client); break; default: fprintf(stderr, "Bogus cmd: %x\n", ctrl->cmd); ctrl->result = -ENOSYS; } pfd.fd = client->ctrl.fd; pfd.events = POLLHUP; if (poll(&pfd, 1, 0) == 1) return -EBADFD; err = write(client->ctrl.fd, buf, 1); if (err != 1) return -EBADFD; if (!client->polling) { add_waiter(client->device.pcm.fd, POLLIN | POLLOUT, pcm_handler, client); client->polling = 1; } return 0; } transport_ops_t pcm_shm_ops = { open: pcm_shm_open, cmd: pcm_shm_cmd, close: pcm_shm_close, }; int ctl_handler(waiter_t *waiter, unsigned short events) { client_t *client = waiter->private_data; char buf[1]; ssize_t n; if (events & POLLIN) { n = write(client->data.fd, buf, 1); if (n != 1) { perrno("write"); return -errno; } } del_waiter(waiter->fd); client->polling = 0; return 0; } int ctl_shm_open(client_t *client, int *cookie) { int shmid; snd_ctl_t *ctl; int err; int result; err = snd_ctl_open(&ctl, client->name); if (err < 0) return err; client->device.control.handle = ctl; client->device.control.fd = snd_ctl_poll_descriptor(ctl); shmid = shmget(IPC_PRIVATE, CTL_SHM_SIZE, 0666); if (shmid < 0) { result = -errno; perrno("shmget"); goto _err; } client->transport.shm.ctrl_id = shmid; client->transport.shm.ctrl = shmat(shmid, 0, 0); if (!client->transport.shm.ctrl) { result = -errno; shmctl(shmid, IPC_RMID, 0); perrno("shmat"); goto _err; } *cookie = shmid; add_waiter(client->device.control.fd, POLLIN, ctl_handler, client); client->polling = 1; return 0; _err: snd_ctl_close(ctl); return result; } int ctl_shm_close(client_t *client) { int err; snd_ctl_client_shm_t *ctrl = client->transport.shm.ctrl; if (client->polling) { del_waiter(client->device.control.fd); client->polling = 0; } /* FIXME: blocking */ err = snd_ctl_close(client->device.control.handle); ctrl->result = err; if (err < 0) perrno("snd_ctl_close"); if (client->transport.shm.ctrl) { err = shmdt((void *)client->transport.shm.ctrl); if (err < 0) perrno("shmdt"); err = shmctl(client->transport.shm.ctrl_id, IPC_RMID, 0); if (err < 0) perrno("shmctl"); client->transport.shm.ctrl = 0; } client->open = 0; return 0; } extern int snd_ctl_read1(snd_ctl_t *ctl, snd_ctl_event_t *event); int ctl_shm_cmd(client_t *client) { snd_ctl_client_shm_t *ctrl = client->transport.shm.ctrl; struct pollfd pfd; char buf[1]; int err; int cmd; snd_ctl_t *ctl; err = read(client->ctrl.fd, buf, 1); if (err != 1) return -EBADFD; cmd = ctrl->cmd; ctrl->cmd = 0; ctl = client->device.control.handle; switch (cmd) { case SND_CTL_IOCTL_HW_INFO: ctrl->result = snd_ctl_hw_info(ctl, &ctrl->u.hw_info); break; case SND_CTL_IOCTL_CONTROL_LIST: { size_t maxsize = CTL_SHM_DATA_MAXLEN; if (ctrl->u.clist.controls_request * sizeof(*ctrl->u.clist.pids) > maxsize) { ctrl->result = -EFAULT; break; } ctrl->u.clist.pids = (snd_control_id_t*) ctrl->data; ctrl->result = snd_ctl_clist(ctl, &ctrl->u.clist); break; } case SND_CTL_IOCTL_CONTROL_INFO: ctrl->result = snd_ctl_cinfo(ctl, &ctrl->u.cinfo); break; case SND_CTL_IOCTL_CONTROL_READ: ctrl->result = snd_ctl_cread(ctl, &ctrl->u.cread); break; case SND_CTL_IOCTL_CONTROL_WRITE: ctrl->result = snd_ctl_cwrite(ctl, &ctrl->u.cwrite); break; case SND_CTL_IOCTL_HWDEP_INFO: ctrl->result = snd_ctl_hwdep_info(ctl, &ctrl->u.hwdep_info); break; case SND_CTL_IOCTL_PCM_INFO: ctrl->result = snd_ctl_pcm_info(ctl, &ctrl->u.pcm_info); break; case SND_CTL_IOCTL_PCM_PREFER_SUBDEVICE: ctrl->result = snd_ctl_pcm_prefer_subdevice(ctl, ctrl->u.pcm_prefer_subdevice); break; case SND_CTL_IOCTL_RAWMIDI_INFO: ctrl->result = snd_ctl_rawmidi_info(ctl, &ctrl->u.rawmidi_info); break; case SND_CTL_IOCTL_READ: ctrl->result = snd_ctl_read1(ctl, &ctrl->u.read); break; case SND_CTL_IOCTL_CLOSE: client->ops->close(client); break; default: fprintf(stderr, "Bogus cmd: %x\n", ctrl->cmd); ctrl->result = -ENOSYS; } pfd.fd = client->ctrl.fd; pfd.events = POLLHUP; if (poll(&pfd, 1, 0) == 1) return -EBADFD; err = write(client->ctrl.fd, buf, 1); if (err != 1) return -EBADFD; if (!client->polling) { add_waiter(client->device.control.fd, POLLIN, ctl_handler, client); client->polling = 1; } return 0; } transport_ops_t ctl_shm_ops = { open: ctl_shm_open, cmd: ctl_shm_cmd, close: ctl_shm_close, }; int snd_client_open(client_t *client) { int err; snd_client_open_request_t req; snd_client_open_answer_t ans; char *name; memset(&ans, 0, sizeof(ans)); err = read(client->ctrl.fd, &req, sizeof(req)); if (err < 0) { perrno("read"); exit(1); } if (err != sizeof(req)) { ans.result = -EINVAL; goto _answer; } name = alloca(req.namelen); err = read(client->ctrl.fd, name, req.namelen); if (err < 0) { perrno("read"); exit(1); } if (err != req.namelen) { ans.result = -EINVAL; goto _answer; } switch (req.dev_type) { case SND_DEV_TYPE_PCM: switch (req.transport_type) { case SND_TRANSPORT_TYPE_SHM: client->ops = &pcm_shm_ops; break; default: ans.result = -EINVAL; goto _answer; } break; case SND_DEV_TYPE_CONTROL: switch (req.transport_type) { case SND_TRANSPORT_TYPE_SHM: client->ops = &ctl_shm_ops; break; default: ans.result = -EINVAL; goto _answer; } break; default: ans.result = -EINVAL; goto _answer; } name[req.namelen] = '\0'; client->transport_type = req.transport_type; strcpy(client->name, name); client->stream = req.stream; client->mode = req.mode; err = client->ops->open(client, &ans.cookie); if (err < 0) { ans.result = err; } else { client->open = 1; ans.result = client->data.fd; } _answer: err = write(client->ctrl.fd, &ans, sizeof(ans)); if (err != sizeof(ans)) { perrno("write"); exit(1); } return 0; } int client_data_handler(waiter_t *waiter, unsigned short events ATTRIBUTE_UNUSED) { client_t *client = waiter->private_data; if (client->open) client->ops->close(client); close(client->data.fd); close(client->ctrl.fd); del_waiter(client->data.fd); del_waiter(client->ctrl.fd); list_del(&client->list); free(client); return 0; } int client_ctrl_handler(waiter_t *waiter, unsigned short events) { client_t *client = waiter->private_data; if (events & POLLHUP) return client_data_handler(waiter, events); if (client->open) return client->ops->cmd(client); else return snd_client_open(client); } int pending_handler(waiter_t *waiter, unsigned short events) { pending_t *pending = waiter->private_data; pending_t *pdata; client_t *client; uint32_t cookie; struct list_head *item; int remove = 0; if (events & POLLHUP) remove = 1; else { int err = read(waiter->fd, &cookie, sizeof(cookie)); if (err != sizeof(cookie)) remove = 1; else { err = write(waiter->fd, &cookie, sizeof(cookie)); if (err != sizeof(cookie)) remove = 1; } } del_waiter(waiter->fd); if (remove) { close(waiter->fd); list_del(&pending->list); free(pending); return 0; } list_for_each(item, &pendings) { pdata = list_entry(item, pending_t, list); if (pdata->cookie == cookie) goto found; } pending->cookie = cookie; return 0; found: client = calloc(sizeof(*client), 1); client->data.fd = pdata->fd; client->data.local = pdata->local; client->ctrl.fd = waiter->fd; client->ctrl.local = pending->local; add_waiter(client->ctrl.fd, POLLIN | POLLHUP, client_ctrl_handler, client); add_waiter(client->data.fd, POLLHUP, client_data_handler, client); client->open = 0; list_add_tail(&client->list, &clients); list_del(&pending->list); list_del(&pdata->list); free(pending); free(pdata); return 0; } int master_handler(waiter_t *waiter, unsigned short events ATTRIBUTE_UNUSED) { master_t *master = waiter->private_data; int sock; sock = accept(waiter->fd, 0, 0); if (sock < 0) { int result = -errno; perrno("accept"); return result; } else { pending_t *pending = calloc(sizeof(*pending), 1); pending->fd = sock; pending->local = master->local; pending->cookie = 0; add_waiter(sock, POLLIN, pending_handler, pending); list_add_tail(&pending->list, &pendings); } return 0; } int server(char *sockname, int port) { struct list_head *item; int err; unsigned int k; if (sockname) { int sock = make_local_socket(sockname); master_t *master; if (sock < 0) return sock; master = calloc(sizeof(*master), 1); master->fd = sock; master->local = 1; add_waiter(sock, POLLIN, master_handler, master); list_add_tail(&master->list, &masters); } if (port >= 0) { int sock = make_inet_socket(port); master_t *master; if (sock < 0) return sock; master = calloc(sizeof(*master), 1); master->fd = sock; master->local = 0; add_waiter(sock, POLLIN, master_handler, master); list_add_tail(&master->list, &masters); } if (list_empty(&masters)) return -EINVAL; list_for_each(item, &masters) { master_t *master = list_entry(item, master_t, list); if (fcntl(master->fd, F_SETFL, O_NONBLOCK) < 0) { int result = -errno; perrno("fcntl"); return result; } if (listen(master->fd, 4) < 0) { int result = -errno; perrno("listen"); return result; } } while (1) { struct pollfd pfds[OPEN_MAX]; size_t pfds_count; do { err = poll(pollfds, pollfds_count, 1000); } while (err == 0); if (err < 0) { perrno("poll"); continue; } pfds_count = pollfds_count; memcpy(pfds, pollfds, sizeof(*pfds) * pfds_count); for (k = 0; k < pfds_count; k++) { struct pollfd *pfd = &pfds[k]; if (pfd->revents) { waiter_t *w = &waiters[pfd->fd]; if (!w->handler) continue; err = w->handler(w, pfd->revents); if (err < 0) perrno("handler"); } } } return 0; } void usage() { fprintf(stderr, "\ Usage: %s [OPTIONS] --help help --version print current version -l,--local SOCKNAME local socket name -p,--port PORT port number ", command); } int main(int argc, char **argv) { static struct option long_options[] = { {"local", 1, 0, 'l'}, {"port", 1, 0, 'p'}, {"help", 0, 0, 'h'} }; int c; char *local = NULL; int port = -1; command = argv[0]; while ((c = getopt_long(argc, argv, "hl:p:", long_options, 0)) != -1) { switch (c) { case 'h': usage(); return 0; case 'l': local = optarg; break; case 'p': port = atoi(optarg); break; default: fprintf(stderr, "Try `%s --help' for more information\n", command); return 1; } } if (!local && port == -1) { fprintf(stderr, "%s: you need to specify at least one master socket\n", command); return 1; } server(local, port); return 0; }