vp9_read_bit_buffer.h convert header statics to global functions
Change-Id: Ibea71b22de898832320d9e49a711a0cb0092901b
diff --git a/vp9/decoder/vp9_read_bit_buffer.c b/vp9/decoder/vp9_read_bit_buffer.c
new file mode 100644
index 0000000..778a635
--- /dev/null
+++ b/vp9/decoder/vp9_read_bit_buffer.c
@@ -0,0 +1,41 @@
+/*
+ * Copyright (c) 2013 The WebM project authors. All Rights Reserved.
+ *
+ * Use of this source code is governed by a BSD-style license
+ * that can be found in the LICENSE file in the root of the source
+ * tree. An additional intellectual property rights grant can be found
+ * in the file PATENTS. All contributing project authors may
+ * be found in the AUTHORS file in the root of the source tree.
+ */
+#include "vp9/decoder/vp9_read_bit_buffer.h"
+
+size_t vp9_rb_bytes_read(struct vp9_read_bit_buffer *rb) {
+ return rb->bit_offset / CHAR_BIT + (rb->bit_offset % CHAR_BIT > 0);
+}
+
+int vp9_rb_read_bit(struct vp9_read_bit_buffer *rb) {
+ const size_t off = rb->bit_offset;
+ const size_t p = off / CHAR_BIT;
+ const int q = CHAR_BIT - 1 - (int)off % CHAR_BIT;
+ if (rb->bit_buffer + p >= rb->bit_buffer_end) {
+ rb->error_handler(rb->error_handler_data);
+ return 0;
+ } else {
+ const int bit = (rb->bit_buffer[p] & (1 << q)) >> q;
+ rb->bit_offset = off + 1;
+ return bit;
+ }
+}
+
+int vp9_rb_read_literal(struct vp9_read_bit_buffer *rb, int bits) {
+ int value = 0, bit;
+ for (bit = bits - 1; bit >= 0; bit--)
+ value |= vp9_rb_read_bit(rb) << bit;
+ return value;
+}
+
+int vp9_rb_read_signed_literal(struct vp9_read_bit_buffer *rb,
+ int bits) {
+ const int value = vp9_rb_read_literal(rb, bits);
+ return vp9_rb_read_bit(rb) ? -value : value;
+}
