[pulseaudio-discuss] [PATCH 1/4] stream-restore: add volume_is_absolute bool in client side

[Marc-André Lureau]

From: Marc-André Lureau <marc-andre.lureau at nokia.com>

While trying to keep ABI compatibility, I introduce a bitfield for the
boolean volume_is_absolute. We can't extend the struct because the
API is using pa_ext_stream_restore_info data[] directly..

Since TEST is not required before calling any other function, I assume
the server side version is at least 1.

Volume is absolute will always be FALSE in v1.
---
 PROTOCOL                       |   13 +++++++++++++
 src/pulse/context.c            |    2 ++
 src/pulse/ext-stream-restore.c |   18 ++++++++++++++----
 src/pulse/ext-stream-restore.h |    4 +++-
 src/pulse/internal.h           |    1 +
 5 files changed, 33 insertions(+), 5 deletions(-)

diff --git a/PROTOCOL b/PROTOCOL
index 88166f1..b14b854 100644
--- a/PROTOCOL
+++ b/PROTOCOL
@@ -181,3 +181,16 @@ new messages:
 
   PA_COMMAND_PLAYBACK_BUFFER_ATTR_CHANGED
   PA_COMMAND_RECORD_BUFFER_ATTR_CHANGED
+
+
+### ext-stream-restore v1, implemented by >= 0.9.12
+
+First version supported.
+
+### ext-stream-restore v2, implemented by >= 0.9.16
+
+First version supported.
+
+SUBCOMMAND_WRITE, SUBCOMMAND_READ
+
+  bool absolute at the end
diff --git a/src/pulse/context.c b/src/pulse/context.c
index bfff0e1..dc80f25 100644
--- a/src/pulse/context.c
+++ b/src/pulse/context.c
@@ -168,6 +168,8 @@ pa_context *pa_context_new_with_proplist(pa_mainloop_api *mainloop, const char *
 
     reset_callbacks(c);
 
+    c->ext_stream_restore.version = 1; /* default version, updated by TEST message */
+
     c->is_local = FALSE;
     c->server_list = NULL;
     c->server = NULL;
diff --git a/src/pulse/ext-stream-restore.c b/src/pulse/ext-stream-restore.c
index 63c911f..dde7222 100644
--- a/src/pulse/ext-stream-restore.c
+++ b/src/pulse/ext-stream-restore.c
@@ -46,7 +46,6 @@ enum {
 
 static void ext_stream_restore_test_cb(pa_pdispatch *pd, uint32_t command, uint32_t tag, pa_tagstruct *t, void *userdata) {
     pa_operation *o = userdata;
-    uint32_t version = PA_INVALID_INDEX;
 
     pa_assert(pd);
     pa_assert(o);
@@ -59,7 +58,7 @@ static void ext_stream_restore_test_cb(pa_pdispatch *pd, uint32_t command, uint3
         if (pa_context_handle_error(o->context, command, t, FALSE) < 0)
             goto finish;
 
-    } else if (pa_tagstruct_getu32(t, &version) < 0 ||
+    } else if (pa_tagstruct_getu32(t, &o->context->ext_stream_restore.version) < 0 ||
                !pa_tagstruct_eof(t)) {
 
         pa_context_fail(o->context, PA_ERR_PROTOCOL);
@@ -68,7 +67,7 @@ static void ext_stream_restore_test_cb(pa_pdispatch *pd, uint32_t command, uint3
 
     if (o->callback) {
         pa_ext_stream_restore_test_cb_t cb = (pa_ext_stream_restore_test_cb_t) o->callback;
-        cb(o->context, version, o->userdata);
+        cb(o->context, o->context->ext_stream_restore.version, o->userdata);
     }
 
 finish:
@@ -125,6 +124,7 @@ static void ext_stream_restore_read_cb(pa_pdispatch *pd, uint32_t command, uint3
         while (!pa_tagstruct_eof(t)) {
             pa_ext_stream_restore_info i;
             pa_bool_t mute = FALSE;
+            pa_bool_t volume_is_absolute = FALSE;
 
             memset(&i, 0, sizeof(i));
 
@@ -138,7 +138,15 @@ static void ext_stream_restore_read_cb(pa_pdispatch *pd, uint32_t command, uint3
                 goto finish;
             }
 
-            i.mute = (int) mute;
+            if (o->context->ext_stream_restore.version >= 2 &&
+                pa_tagstruct_get_boolean(t, &volume_is_absolute) < 0) {
+
+                pa_context_fail(o->context, PA_ERR_PROTOCOL);
+                goto finish;
+            }
+
+	    i.mute = (int) mute;
+	    i.volume_is_absolute = volume_is_absolute;
 
             if (o->callback) {
                 pa_ext_stream_restore_read_cb_t cb = (pa_ext_stream_restore_read_cb_t) o->callback;
@@ -231,6 +239,8 @@ pa_operation *pa_ext_stream_restore_write(
         pa_tagstruct_put_cvolume(t, &data->volume);
         pa_tagstruct_puts(t, data->device);
         pa_tagstruct_put_boolean(t, data->mute);
+        if (c->ext_stream_restore.version >= 2)
+            pa_tagstruct_put_boolean(t, data->volume_is_absolute);
     }
 
     pa_pstream_send_tagstruct(c->pstream, t);
diff --git a/src/pulse/ext-stream-restore.h b/src/pulse/ext-stream-restore.h
index 0b5d8eb..14d984e 100644
--- a/src/pulse/ext-stream-restore.h
+++ b/src/pulse/ext-stream-restore.h
@@ -24,6 +24,7 @@
 
 #include <pulse/context.h>
 #include <pulse/version.h>
+#include <pulsecore/macro.h>
 
 /** \file
  *
@@ -39,7 +40,8 @@ typedef struct pa_ext_stream_restore_info {
     pa_channel_map channel_map;  /**< The channel map for the volume field, if applicable */
     pa_cvolume volume;           /**< The volume of the stream when it was seen last, if applicable and saved */
     const char *device;          /**< The sink/source of the stream when it was last seen, if applicable and saved */
-    int mute;                    /**< The boolean mute state of the stream when it was last seen, if applicable and saved */
+    int mute:1;                  /**< The boolean mute state of the stream when it was last seen, if applicable and saved */
+    pa_bool_t volume_is_absolute:1; /**< True if the volume is absolute, if applicable and saved.  \since 0.9.16 */
 } pa_ext_stream_restore_info;
 
 /** Callback prototype for pa_ext_stream_restore_test(). \since 0.9.12 */
diff --git a/src/pulse/internal.h b/src/pulse/internal.h
index 28a989b..3c58c49 100644
--- a/src/pulse/internal.h
+++ b/src/pulse/internal.h
@@ -103,6 +103,7 @@ struct pa_context {
     struct {
         pa_ext_stream_restore_subscribe_cb_t callback;
         void *userdata;
+        uint32_t version;
     } ext_stream_restore;
 };
 
-- 
1.6.2.4