1 files changed, 85 insertions, 0 deletions
diff --git a/src/pcm/pcm_buffer.h b/src/pcm/pcm_buffer.h
new file mode 100644
index 000000000..5d6382d5e
--- /dev/null
+++ b/src/pcm/pcm_buffer.h
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2003-2011 The Music Player Daemon Project
+ * http://www.musicpd.org
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License along
+ * with this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#ifndef PCM_BUFFER_H
+#define PCM_BUFFER_H
+
+#include "check.h"
+
+#include <glib.h>
+
+#include <assert.h>
+
+/**
+ * Manager for a temporary buffer which grows as needed.  We could
+ * allocate a new buffer every time pcm_convert() is called, but that
+ * would put too much stress on the allocator.
+ */
+struct pcm_buffer {
+	void *buffer;
+
+	size_t size;
+};
+
+/**
+ * Initialize the buffer, but don't allocate anything yet.
+ */
+static inline void
+pcm_buffer_init(struct pcm_buffer *buffer)
+{
+	assert(buffer != NULL);
+
+	buffer->buffer = NULL;
+	buffer->size = 0;
+}
+
+/**
+ * Free resources.  This function may be called more than once.
+ */
+static inline void
+pcm_buffer_deinit(struct pcm_buffer *buffer)
+{
+	assert(buffer != NULL);
+
+	g_free(buffer->buffer);
+
+	buffer->buffer = NULL;
+}
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * Get the buffer, and guarantee a minimum size.  This buffer becomes
+ * invalid with the next pcm_buffer_get() call.
+ *
+ * This function will never return NULL, even if size is zero, because
+ * the PCM library uses the NULL return value to signal "error".  An
+ * empty destination buffer is not always an error.
+ */
+G_GNUC_MALLOC
+void *
+pcm_buffer_get(struct pcm_buffer *buffer, size_t size);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif