alsactl: add event filter and cache for the daemon mode

Signed-off-by: Jaroslav Kysela <perex@perex.cz>

diff --git a/alsactl/alsactl.c b/alsactl/alsactl.c
index 3864028e6f005270d892bda0664dede375eb4dec..8a4d9ee1dc021f34abdfb6a1cf38c52ace588953 100644 (file)
--- a/alsactl/alsactl.c
+++ b/alsactl/alsactl.c
@@ -189,7 +189,6 @@ int main(int argc, char *argv[])
        }
        short_option[k] = '\0';
        command = argv[0];
-       printf("short_option = '%s'\n", short_option);
        while (1) {
                int c;
 

diff --git a/alsactl/daemon.c b/alsactl/daemon.c
index 940c080050102ab712ee690d261b66f71f37115e..34056a33f9d56e86821a0537fde655630baec404 100644 (file)
--- a/alsactl/daemon.c
+++ b/alsactl/daemon.c
@@ -32,10 +32,17 @@
 #include <alsa/asoundlib.h>
 #include "alsactl.h"
 
+struct id_list {
+       snd_ctl_elem_id_t **list;
+       int size;
+};
+
 struct card {
        int index;
        int pfds;
        snd_ctl_t *handle;
+       struct id_list whitelist;
+       struct id_list blacklist;
 };
 
 static int quit = 0;
@@ -60,9 +67,21 @@ static void signal_handler_rescan(int sig)
        signal(sig, signal_handler_rescan);
 }
 
+static void free_list(struct id_list *list)
+{
+       int i;
+
+       for (i = 0; i < list->size; i++)
+               free(list->list[i]);
+       free(list->list);
+}
+
 static void card_free(struct card **card)
 {
        struct card *c = *card;
+
+       free_list(&c->blacklist);
+       free_list(&c->whitelist);
        if (c->handle)
                snd_ctl_close(c->handle);
        free(c);
@@ -135,18 +154,125 @@ static void add_cards(struct card ***cards, int *count)
        }
 }
 
-int card_events(struct card *card)
+static int compare_ids(snd_ctl_elem_id_t *id1, snd_ctl_elem_id_t *id2)
+{
+       if (id1 == NULL || id2 == NULL)
+               return 0;
+       return snd_ctl_elem_id_get_interface(id1) == snd_ctl_elem_id_get_interface(id2) &&
+              snd_ctl_elem_id_get_index(id1) == snd_ctl_elem_id_get_index(id2) &&
+              strcmp(snd_ctl_elem_id_get_name(id1), snd_ctl_elem_id_get_name(id2)) == 0 &&
+              snd_ctl_elem_id_get_device(id1) == snd_ctl_elem_id_get_device(id2) &&
+              snd_ctl_elem_id_get_subdevice(id1) == snd_ctl_elem_id_get_subdevice(id2);
+}
+
+static int in_list(struct id_list *list, snd_ctl_elem_id_t *id)
+{
+       int i;
+       snd_ctl_elem_id_t *id1;
+
+       for (i = 0; i < list->size; i++) {
+               id1 = list->list[i];
+               if (id1 == NULL)
+                       continue;
+               if (compare_ids(id, id1))
+                       return 1;
+       }
+       return 0;
+}
+
+static void remove_from_list(struct id_list *list, snd_ctl_elem_id_t *id)
+{
+       int i;
+
+       for (i = 0; i < list->size; i++) {
+               if (compare_ids(id, list->list[i])) {
+                       free(list->list[i]);
+                       list->list[i] = NULL;
+               }
+       }
+}
+
+static void add_to_list(struct id_list *list, snd_ctl_elem_id_t *id)
+{
+       snd_ctl_elem_id_t *id1;
+       snd_ctl_elem_id_t **n;
+       int i;
+
+       if (snd_ctl_elem_id_malloc(&id1))
+               return;
+       snd_ctl_elem_id_copy(id1, id);
+       for (i = 0; i < list->size; i++) {
+               if (list->list[i] == NULL) {
+                       list->list[i] = id1;
+                       return;
+               }
+       }
+       n = realloc(list->list, sizeof(void *) * (list->size + 1));
+       if (n == NULL)
+               return;
+       n[list->size] = id1;
+       list->size++;
+       list->list = n;
+}
+
+static int check_lists(struct card *card, snd_ctl_elem_id_t *id)
+{
+       snd_ctl_elem_info_t *info;
+       snd_ctl_elem_info_alloca(&info);
+
+       if (in_list(&card->blacklist, id))
+               return 0;
+       if (in_list(&card->whitelist, id))
+               return 1;
+       snd_ctl_elem_info_set_id(info, id);
+       if (snd_ctl_elem_info(card->handle, info) < 0)
+               return 0;
+       if (snd_ctl_elem_info_is_writable(info) ||
+           snd_ctl_elem_info_is_tlv_writable(info)) {
+               add_to_list(&card->whitelist, id);
+               return 1;
+       } else {
+               add_to_list(&card->blacklist, id);
+               return 0;
+       }
+}
+
+static int card_events(struct card *card)
 {
        int res = 0;
        snd_ctl_event_t *ev;
+       snd_ctl_event_type_t type;
+       unsigned int mask;
+       snd_ctl_elem_id_t *id;
        snd_ctl_event_alloca(&ev);
+       snd_ctl_elem_id_alloca(&id);
 
-       while (snd_ctl_read(card->handle, ev) == 1)
-               res = 1;
+       while (snd_ctl_read(card->handle, ev) == 1) {
+               type = snd_ctl_event_get_type(ev);
+               if (type != SND_CTL_EVENT_ELEM)
+                       continue;
+               mask = snd_ctl_event_elem_get_mask(ev);
+               snd_ctl_event_elem_get_id(ev, id);
+               if (mask == SND_CTL_EVENT_MASK_REMOVE) {
+                       remove_from_list(&card->whitelist, id);
+                       remove_from_list(&card->blacklist, id);
+                       continue;
+               }
+               if (mask & SND_CTL_EVENT_MASK_INFO) {
+                       remove_from_list(&card->whitelist, id);
+                       remove_from_list(&card->blacklist, id);
+               }
+               if (mask & (SND_CTL_EVENT_MASK_VALUE|
+                           SND_CTL_EVENT_MASK_ADD|
+                           SND_CTL_EVENT_MASK_TLV)) {
+                       if (check_lists(card, id))
+                               res = 1;
+               }
+       }
        return res;
 }
 
-long read_pid_file(const char *pidfile)
+static long read_pid_file(const char *pidfile)
 {
        int fd, err;
        char pid_txt[12];
@@ -164,7 +290,7 @@ long read_pid_file(const char *pidfile)
        }
 }
 
-int write_pid_file(const char *pidfile)
+static int write_pid_file(const char *pidfile)
 {
        int fd, err;
        char pid_txt[12];
@@ -214,7 +340,7 @@ int state_daemon_kill(const char *pidfile, const char *cmd)
        return 0;
 }
 
-int check_another_instance(const char *pidfile)
+static int check_another_instance(const char *pidfile)
 {
        long pid;