core: Add a second rw mempool

To keep the data and the ringbuffer separate, let's add another
mempool just for the ringbuffer(s). That way, the client can open
the ringbuffer shm file in rw mode and keep the data in ro mode.

Signed-off-by: David Henningsson <david.henningsson@canonical.com>

diff --git a/src/pulsecore/core.c b/src/pulsecore/core.c
index e6f2dfcba97fb4b92b7bf16cbfd2f1b543196971..b0f231498212551068ff94dcfe281967e143eec4 100644 (file)
--- a/src/pulsecore/core.c
+++ b/src/pulsecore/core.c
@@ -127,6 +127,11 @@ pa_core* pa_core_new(pa_mainloop_api *m, bool shared, size_t shm_size) {
     c->mempool = pool;
     pa_silence_cache_init(&c->silence_cache);
 
+    if (shared && !(c->rw_mempool = pa_mempool_new(shared, shm_size)))
+        pa_log_warn("failed to allocate shared writable memory pool.");
+    if (c->rw_mempool)
+        pa_mempool_set_is_remote_writable(c->rw_mempool, true);
+
     c->exit_event = NULL;
 
     c->exit_idle_time = -1;
@@ -208,6 +213,8 @@ static void core_free(pa_object *o) {
     pa_assert(!c->default_sink);
 
     pa_silence_cache_done(&c->silence_cache);
+    if (c->rw_mempool)
+        pa_mempool_free(c->rw_mempool);
     pa_mempool_free(c->mempool);
 
     for (j = 0; j < PA_CORE_HOOK_MAX; j++)
@@ -254,7 +261,6 @@ void pa_core_maybe_vacuum(pa_core *c) {
 
     if (pa_idxset_isempty(c->sink_inputs) && pa_idxset_isempty(c->source_outputs)) {
         pa_log_debug("Hmm, no streams around, trying to vacuum.");
-        pa_mempool_vacuum(c->mempool);
     } else {
         pa_sink *si;
         pa_source *so;
@@ -271,8 +277,12 @@ void pa_core_maybe_vacuum(pa_core *c) {
                 return;
 
         pa_log_info("All sinks and sources are suspended, vacuuming memory");
-        pa_mempool_vacuum(c->mempool);
     }
+
+    pa_mempool_vacuum(c->mempool);
+
+    if (c->rw_mempool)
+        pa_mempool_vacuum(c->rw_mempool);
 }
 
 pa_time_event* pa_core_rttime_new(pa_core *c, pa_usec_t usec, pa_time_event_cb_t cb, void *userdata) {

diff --git a/src/pulsecore/core.h b/src/pulsecore/core.h
index b443ce4a82cd47af98bd59c18a04a5c04040571a..1f9df73e3e2faa35d94e543a4cf4787b6b927aba 100644 (file)
--- a/src/pulsecore/core.h
+++ b/src/pulsecore/core.h
@@ -170,7 +170,10 @@ struct pa_core {
     PA_LLIST_HEAD(pa_subscription_event, subscription_event_queue);
     pa_subscription_event *subscription_event_last;
 
-    pa_mempool *mempool;
+    /* The mempool is used for data we write to, it's readonly for the client.
+       The rw_mempool is used for data writable by both server and client (and
+       can be NULL in some cases). */
+    pa_mempool *mempool, *rw_mempool;
     pa_silence_cache silence_cache;
 
     pa_time_event *exit_event;