[pulseaudio-discuss] [PATCH v2 3/4] protocol-native: add "ext_supported" to install_ext()

[Marc-André Lureau]

In order to support different extensions versions in the same module,
it introduces an array of supported extension strings. They are free
form (freely matched by extension).
---
 src/modules/module-stream-restore.c |    3 +-
 src/pulsecore/protocol-native.c     |   44 +++++++++++++++++++++++++++++-----
 src/pulsecore/protocol-native.h     |    4 ++-
 3 files changed, 42 insertions(+), 9 deletions(-)

diff --git a/src/modules/module-stream-restore.c b/src/modules/module-stream-restore.c
index 4ff6c57..db30528 100644
--- a/src/modules/module-stream-restore.c
+++ b/src/modules/module-stream-restore.c
@@ -807,6 +807,7 @@ int pa__init(pa_module*m) {
     uint32_t idx;
     pa_bool_t restore_device = TRUE, restore_volume = TRUE, restore_muted = TRUE;
     int gdbm_cache_size;
+    const char* ext_supported[] = { "stream-restore-1", "stream-restore-2", NULL };
 
     pa_assert(m);
 
@@ -836,7 +837,7 @@ int pa__init(pa_module*m) {
     u->subscribed = pa_idxset_new(pa_idxset_trivial_hash_func, pa_idxset_trivial_compare_func);
 
     u->protocol = pa_native_protocol_get(m->core);
-    pa_native_protocol_install_ext(u->protocol, m, extension_cb);
+    pa_native_protocol_install_ext(u->protocol, m, extension_cb, ext_supported);
 
     u->connection_unlink_hook_slot = pa_hook_connect(&pa_native_protocol_hooks(u->protocol)[PA_NATIVE_HOOK_CONNECTION_UNLINK], PA_HOOK_NORMAL, (pa_hook_cb_t) connection_unlink_hook_cb, u);
 
diff --git a/src/pulsecore/protocol-native.c b/src/pulsecore/protocol-native.c
index aecaf71..5db080f 100644
--- a/src/pulsecore/protocol-native.c
+++ b/src/pulsecore/protocol-native.c
@@ -159,6 +159,11 @@ PA_DECLARE_CLASS(upload_stream);
 #define UPLOAD_STREAM(o) (upload_stream_cast(o))
 static PA_DEFINE_CHECK_TYPE(upload_stream, output_stream);
 
+typedef struct native_protocol_ext {
+    pa_native_protocol_ext_cb_t cb;
+    pa_strlist *supported;
+} native_protocol_ext;
+
 struct pa_native_connection {
     pa_msgobject parent;
     pa_native_protocol *protocol;
@@ -4149,7 +4154,7 @@ static void command_extension(pa_pdispatch *pd, uint32_t command, uint32_t tag,
     uint32_t idx = PA_INVALID_INDEX;
     const char *name = NULL;
     pa_module *m;
-    pa_native_protocol_ext_cb_t cb;
+    native_protocol_ext *ext;
 
     pa_native_connection_assert_ref(c);
     pa_assert(t);
@@ -4177,10 +4182,11 @@ static void command_extension(pa_pdispatch *pd, uint32_t command, uint32_t tag,
     CHECK_VALIDITY(c->pstream, m, tag, PA_ERR_NOEXTENSION);
     CHECK_VALIDITY(c->pstream, m->load_once || idx != PA_INVALID_INDEX, tag, PA_ERR_INVALID);
 
-    cb = (pa_native_protocol_ext_cb_t) (unsigned long) pa_hashmap_get(c->protocol->extensions, m);
-    CHECK_VALIDITY(c->pstream, cb, tag, PA_ERR_NOEXTENSION);
+    ext = (native_protocol_ext *) pa_hashmap_get(c->protocol->extensions, m);
+    CHECK_VALIDITY(c->pstream, ext, tag, PA_ERR_NOEXTENSION);
+    CHECK_VALIDITY(c->pstream, ext->cb, tag, PA_ERR_NOEXTENSION);
 
-    if (cb(c->protocol, m, c, tag, t) < 0)
+    if (ext->cb(c->protocol, m, c, tag, t) < 0)
         protocol_error(c);
 }
 
@@ -4532,6 +4538,15 @@ pa_native_protocol* pa_native_protocol_ref(pa_native_protocol *p) {
     return p;
 }
 
+static void extension_free(void *p, void *userdata) {
+    native_protocol_ext *ext;
+
+    pa_assert_se(ext = p);
+
+    pa_strlist_free(ext->supported);
+    pa_xfree(ext);
+}
+
 void pa_native_protocol_unref(pa_native_protocol *p) {
     pa_native_connection *c;
     pa_native_hook_t h;
@@ -4552,7 +4567,7 @@ void pa_native_protocol_unref(pa_native_protocol *p) {
     for (h = 0; h < PA_NATIVE_HOOK_MAX; h++)
         pa_hook_done(&p->hooks[h]);
 
-    pa_hashmap_free(p->extensions, NULL, NULL);
+    pa_hashmap_free(p->extensions, extension_free, NULL);
 
     pa_assert_se(pa_shared_remove(p->core, "native-protocol") >= 0);
 
@@ -4593,23 +4608,38 @@ pa_strlist *pa_native_protocol_servers(pa_native_protocol *p) {
     return p->servers;
 }
 
-int pa_native_protocol_install_ext(pa_native_protocol *p, pa_module *m, pa_native_protocol_ext_cb_t cb) {
+int pa_native_protocol_install_ext(pa_native_protocol *p, pa_module *m, pa_native_protocol_ext_cb_t cb, const char *ext_supported[]) {
+    native_protocol_ext *ext;
+    unsigned i;
+
     pa_assert(p);
     pa_assert(PA_REFCNT_VALUE(p) >= 1);
     pa_assert(m);
     pa_assert(cb);
+    pa_assert(ext_supported);
+    pa_assert(ext_supported[0]);
     pa_assert(!pa_hashmap_get(p->extensions, m));
 
-    pa_assert_se(pa_hashmap_put(p->extensions, m, (void*) (unsigned long) cb) == 0);
+    ext = pa_xnew(native_protocol_ext, 1);
+    ext->cb = cb;
+    ext->supported = NULL;
+    for (i = 0; ext_supported[i] != NULL; ++i)
+        ext->supported = pa_strlist_prepend(ext->supported, ext_supported[i]);
+
+    pa_assert_se(pa_hashmap_put(p->extensions, m, ext) == 0);
     return 0;
 }
 
 void pa_native_protocol_remove_ext(pa_native_protocol *p, pa_module *m) {
+    native_protocol_ext *ext;
+
     pa_assert(p);
     pa_assert(PA_REFCNT_VALUE(p) >= 1);
     pa_assert(m);
 
+    pa_assert_se(ext = (native_protocol_ext *) pa_hashmap_get(p->extensions, m));
     pa_assert_se(pa_hashmap_remove(p->extensions, m));
+    extension_free(ext, NULL);
 }
 
 pa_native_options* pa_native_options_new(void) {
diff --git a/src/pulsecore/protocol-native.h b/src/pulsecore/protocol-native.h
index 8a8d601..7bd159a 100644
--- a/src/pulsecore/protocol-native.h
+++ b/src/pulsecore/protocol-native.h
@@ -76,7 +76,9 @@ typedef int (*pa_native_protocol_ext_cb_t)(
         uint32_t tag,
         pa_tagstruct *t);
 
-int pa_native_protocol_install_ext(pa_native_protocol *p, pa_module *m, pa_native_protocol_ext_cb_t cb);
+/* "extensions_supported" is used to identify extension name and version supported by the module.
+ * ex: ext_supported = { "stream-restore", "stream-restore-2", NULL } */
+int pa_native_protocol_install_ext(pa_native_protocol *p, pa_module *m, pa_native_protocol_ext_cb_t cb, const char *ext_supported[]);
 void pa_native_protocol_remove_ext(pa_native_protocol *p, pa_module *m);
 
 pa_pstream* pa_native_connection_get_pstream(pa_native_connection *c);
-- 
1.6.2.4