add new API call pa_cvolume_compatible()

src/map-file

@@ -98,6 +98,7 @@ pa_context_unload_module;
 pa_context_unref;
 pa_cvolume_avg;
 pa_cvolume_channels_equal_to;
+pa_cvolume_compatible;
 pa_cvolume_equal;
 pa_cvolume_max;
 pa_cvolume_remap;

src/pulse/volume.c

@@ -325,3 +325,17 @@ pa_cvolume *pa_cvolume_remap(pa_cvolume *v, pa_channel_map *from, pa_channel_map
     *v = result;
     return v;
 }
+
+int pa_cvolume_compatible(const pa_cvolume *v, const pa_sample_spec *ss) {
+
+    pa_assert(v);
+    pa_assert(ss);
+
+    if (!pa_cvolume_valid(v))
+        return 0;
+
+    if (!pa_sample_spec_valid(ss))
+        return 0;
+
+    return v->channels == ss->channels;
+}

src/pulse/volume.h

@@ -192,6 +192,10 @@ double pa_sw_volume_to_linear(pa_volume_t v) PA_GCC_CONST;
 /** Remap a volume from one channel mapping to a different channel mapping. \since 0.9.12 */
 pa_cvolume *pa_cvolume_remap(pa_cvolume *v, pa_channel_map *from, pa_channel_map *to);
 
+/** Return non-zero if the specified volume is compatible with
+ * the specified sample spec. \since 0.9.13 */
+int pa_cvolume_compatible(const pa_cvolume *v, const pa_sample_spec *ss) PA_GCC_PURE;
+
 PA_C_DECL_END
 
 #endif