1 files changed, 84 insertions, 0 deletions
diff --git a/src/pulsecore/stream-util.c b/src/pulsecore/stream-util.c
new file mode 100644
index 0000000..2574501
--- /dev/null
+++ b/src/pulsecore/stream-util.c
@@ -0,0 +1,84 @@
+/***
+  This file is part of PulseAudio.
+
+  Copyright 2013 Intel Corporation
+
+  PulseAudio is free software; you can redistribute it and/or modify
+  it under the terms of the GNU Lesser General Public License as published
+  by the Free Software Foundation; either version 2.1 of the License,
+  or (at your option) any later version.
+
+  PulseAudio is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with PulseAudio; if not, see <http://www.gnu.org/licenses/>.
+***/
+
+#ifdef HAVE_CONFIG_H
+#include <config.h>
+#endif
+
+#include "stream-util.h"
+
+#include <pulse/def.h>
+
+#include <pulsecore/core-format.h>
+#include <pulsecore/macro.h>
+
+int pa_stream_get_volume_channel_map(const pa_cvolume *volume, const pa_channel_map *original_map, const pa_format_info *format,
+                                     pa_channel_map *volume_map) {
+    int r;
+    pa_channel_map volume_map_local;
+
+    pa_assert(volume);
+    pa_assert(format);
+    pa_assert(volume_map);
+
+    if (original_map) {
+        if (volume->channels == original_map->channels) {
+            *volume_map = *original_map;
+            return 0;
+        }
+
+        if (volume->channels == 1) {
+            pa_channel_map_init_mono(volume_map);
+            return 0;
+        }
+
+        pa_log_info("Invalid stream parameters: the volume is incompatible with the channel map.");
+        return -PA_ERR_INVALID;
+    }
+
+    r = pa_format_info_get_channel_map(format, &volume_map_local);
+    if (r == -PA_ERR_NOENTITY) {
+        if (volume->channels == 1) {
+            pa_channel_map_init_mono(volume_map);
+            return 0;
+        }
+
+        pa_log_info("Invalid stream parameters: multi-channel volume is set, but channel map is not.");
+        return -PA_ERR_INVALID;
+    }
+
+    if (r < 0) {
+        pa_log_info("Invalid channel map.");
+        return -PA_ERR_INVALID;
+    }
+
+    if (volume->channels == volume_map_local.channels) {
+        *volume_map = volume_map_local;
+        return 0;
+    }
+
+    if (volume->channels == 1) {
+        pa_channel_map_init_mono(volume_map);
+        return 0;
+    }
+
+    pa_log_info("Invalid stream parameters: the volume is incompatible with the channel map.");
+
+    return -PA_ERR_INVALID;
+}