alsactl: use a list of source for event dispatcher instead of an array of source

In a previous commit, handlers of control nodes are maintained by link
list.

This commit uses the list to register/unregister event sources to
dispatcher.

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Jaroslav Kysela <perex@perex.cz>

diff --git a/alsactl/monitor.c b/alsactl/monitor.c
index 7a61f9cd515db64cb178fd8776aba0002fb6c56d..878d003d08b7cc02a3fa7803c8c00e8acf9b1d80 100644 (file)
--- a/alsactl/monitor.c
+++ b/alsactl/monitor.c
@@ -68,6 +68,8 @@ static const char *snd_card_iterator_next(struct snd_card_iterator *iter)
 static void remove_source_entry(struct src_entry *entry)
 {
        list_del(&entry->list);
+       if (entry->handle)
+               snd_ctl_close(entry->handle);
        free(entry->name);
        free(entry);
 }
@@ -138,7 +140,7 @@ static int open_ctl(const char *name, snd_ctl_t **ctlp)
        return 0;
 }
 
-static int print_event(int card, snd_ctl_t *ctl)
+static int print_event(snd_ctl_t *ctl, const char *name)
 {
        snd_ctl_event_t *event;
        unsigned int mask;
@@ -152,9 +154,8 @@ static int print_event(int card, snd_ctl_t *ctl)
        if (snd_ctl_event_get_type(event) != SND_CTL_EVENT_ELEM)
                return 0;
 
-       if (card >= 0)
-               printf("card %d, ", card);
-       printf("#%d (%i,%i,%i,%s,%i)",
+       printf("node %s, #%d (%i,%i,%i,%s,%i)",
+              name,
               snd_ctl_event_elem_get_numid(event),
               snd_ctl_event_elem_get_interface(event),
               snd_ctl_event_elem_get_device(event),
@@ -181,36 +182,28 @@ static int print_event(int card, snd_ctl_t *ctl)
 }
 
 static int operate_dispatcher(int epfd, uint32_t op, struct epoll_event *epev,
-                             snd_ctl_t *ctl)
+                             struct src_entry *entry)
 {
        struct pollfd *pfds;
        int count;
-       unsigned int pfd_count;
        int i;
-       int err;
-
-       count = snd_ctl_poll_descriptors_count(ctl);
-       if (count < 0)
-               return count;
-       if (count == 0)
-               return -ENXIO;
-       pfd_count = count;
+       int err = 0;
 
-       pfds = calloc(pfd_count, sizeof(*pfds));
+       pfds = calloc(entry->pfd_count, sizeof(*pfds));
        if (!pfds)
                return -ENOMEM;
 
-       count = snd_ctl_poll_descriptors(ctl, pfds, pfd_count);
+       count = snd_ctl_poll_descriptors(entry->handle, pfds, entry->pfd_count);
        if (count < 0) {
                err = count;
                goto end;
        }
-       if (count != pfd_count) {
+       if (count != entry->pfd_count) {
                err = -EIO;
                goto end;
        }
 
-       for (i = 0; i < pfd_count; ++i) {
+       for (i = 0; i < entry->pfd_count; ++i) {
                err = epoll_ctl(epfd, op, pfds[i].fd, epev);
                if (err < 0)
                        break;
@@ -220,17 +213,16 @@ end:
        return err;
 }
 
-static int prepare_dispatcher(int epfd, snd_ctl_t **ctls, int ncards)
+static int prepare_dispatcher(int epfd, struct list_head *srcs)
 {
-       int i;
+       struct src_entry *entry;
        int err = 0;
 
-       for (i = 0; i < ncards; ++i) {
-               snd_ctl_t *ctl = ctls[i];
+       list_for_each_entry(entry, srcs, list) {
                struct epoll_event ev;
                ev.events = EPOLLIN;
-               ev.data.ptr = (void *)ctl;
-               err = operate_dispatcher(epfd, EPOLL_CTL_ADD, &ev, ctl);
+               ev.data.ptr = (void *)entry;
+               err = operate_dispatcher(epfd, EPOLL_CTL_ADD, &ev, entry);
                if (err < 0)
                        break;
        }
@@ -238,11 +230,17 @@ static int prepare_dispatcher(int epfd, snd_ctl_t **ctls, int ncards)
        return err;
 }
 
-static int run_dispatcher(int epfd, unsigned int max_ev_count, int show_cards)
+static int run_dispatcher(int epfd, struct list_head *srcs)
 {
+       struct src_entry *entry;
+       unsigned int max_ev_count;
        struct epoll_event *epev;
        int err = 0;
 
+       max_ev_count = 0;
+       list_for_each_entry(entry, srcs, list)
+               max_ev_count += entry->pfd_count;
+
        epev = calloc(max_ev_count, sizeof(*epev));
        if (!epev)
                return -ENOMEM;
@@ -261,10 +259,9 @@ static int run_dispatcher(int epfd, unsigned int max_ev_count, int show_cards)
 
                for (i = 0; i < count; ++i) {
                        struct epoll_event *ev = epev + i;
-                       snd_ctl_t *handle = (snd_ctl_t *)ev->data.ptr;
-
+                       struct src_entry *entry = (struct src_entry *)ev->data.ptr;
                        if (ev->events & EPOLLIN)
-                               print_event(show_cards ? i : -1, handle);
+                               print_event(entry->handle, entry->name);
                }
        }
 
@@ -273,14 +270,12 @@ static int run_dispatcher(int epfd, unsigned int max_ev_count, int show_cards)
        return err;
 }
 
-static void clear_dispatcher(int epfd, snd_ctl_t **ctls, int ncards)
+static void clear_dispatcher(int epfd, struct list_head *srcs)
 {
-       int i;
+       struct src_entry *entry;
 
-       for (i = 0; i < ncards; ++i) {
-               snd_ctl_t *ctl = ctls[i];
-               operate_dispatcher(epfd, EPOLL_CTL_DEL, NULL, ctl);
-       }
+       list_for_each_entry(entry, srcs, list)
+               operate_dispatcher(epfd, EPOLL_CTL_DEL, NULL, entry);
 }
 
 int monitor(const char *name)
@@ -288,9 +283,7 @@ int monitor(const char *name)
        LIST_HEAD(srcs);
        snd_ctl_t *ctls[MAX_CARDS] = {0};
        int ncards = 0;
-       int show_cards;
        int epfd;
-       int i;
        int err = 0;
 
        epfd = epoll_create(1);
@@ -311,7 +304,6 @@ int monitor(const char *name)
                                goto error;
                        ncards++;
                }
-               show_cards = 1;
        } else {
                err = open_ctl(name, &ctls[0]);
                if (err < 0)
@@ -320,20 +312,14 @@ int monitor(const char *name)
                if (err < 0)
                        goto error;
                ncards++;
-               show_cards = 0;
        }
 
-       err = prepare_dispatcher(epfd, ctls, ncards);
+       err = prepare_dispatcher(epfd, &srcs);
        if (err >= 0)
-               err = run_dispatcher(epfd, ncards, show_cards);
-       clear_dispatcher(epfd, ctls, ncards);
-
+               err = run_dispatcher(epfd, &srcs);
+       clear_dispatcher(epfd, &srcs);
 error:
        clear_source_list(&srcs);
-       for (i = 0; i < ncards; i++) {
-               if (ctls[i])
-                       snd_ctl_close(ctls[i]);
-       }
 
        close(epfd);