vp9: add extern "C" to headers

Change-Id: I1b6927ad820f99340985b094d415aaab14defaf4

vp9/common/vp9_thread_common.h

@@ -14,6 +14,10 @@
 #include "vp9/common/vp9_loopfilter.h"
 #include "vpx_util/vpx_thread.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 struct VP9Common;
 struct FRAME_COUNTS;
 
@@ -54,4 +58,8 @@ void vp9_loop_filter_frame_mt(YV12_BUFFER_CONFIG *frame,
 void vp9_accumulate_frame_counts(struct VP9Common *cm,
                                  struct FRAME_COUNTS *counts, int is_dec);
 
+#ifdef __cplusplus
+}  // extern "C"
+#endif
+
 #endif  // VP9_COMMON_VP9_LOOPFILTER_THREAD_H_

vp9/decoder/vp9_dthread.h

@@ -15,6 +15,10 @@
 #include "vpx_util/vpx_thread.h"
 #include "vpx/internal/vpx_codec_internal.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 struct VP9Common;
 struct VP9Decoder;
 
@@ -63,4 +67,8 @@ void vp9_frameworker_broadcast(RefCntBuffer *const buf, int row);
 void vp9_frameworker_copy_context(VPxWorker *const dst_worker,
                                   VPxWorker *const src_worker);
 
+#ifdef __cplusplus
+}    // extern "C"
+#endif
+
 #endif  // VP9_DECODER_VP9_DTHREAD_H_

vp9/encoder/vp9_context_tree.h

@@ -14,6 +14,10 @@
 #include "vp9/common/vp9_blockd.h"
 #include "vp9/encoder/vp9_block.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 struct VP9_COMP;
 struct VP9Common;
 struct ThreadData;
@@ -84,4 +88,8 @@ typedef struct PC_TREE {
 void vp9_setup_pc_tree(struct VP9Common *cm, struct ThreadData *td);
 void vp9_free_pc_tree(struct ThreadData *td);
 
+#ifdef __cplusplus
+}  // extern "C"
+#endif
+
 #endif /* VP9_ENCODER_VP9_CONTEXT_TREE_H_ */

vp9/encoder/vp9_ethread.h

@@ -11,6 +11,10 @@
 #ifndef VP9_ENCODER_VP9_ETHREAD_H_
 #define VP9_ENCODER_VP9_ETHREAD_H_
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 struct VP9_COMP;
 struct ThreadData;
 
@@ -22,4 +26,8 @@ typedef struct EncWorkerData {
 
 void vp9_encode_tiles_mt(struct VP9_COMP *cpi);
 
+#ifdef __cplusplus
+}  // extern "C"
+#endif
+
 #endif  // VP9_ENCODER_VP9_ETHREAD_H_

vp9/encoder/vp9_resize.h

@@ -14,6 +14,10 @@
 #include <stdio.h>
 #include "vpx/vpx_integer.h"
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 void vp9_resize_plane(const uint8_t *const input,
                       int height,
                       int width,
@@ -121,4 +125,9 @@ void vp9_highbd_resize_frame444(const uint8_t *const y,
                                 int owidth,
                                 int bd);
 #endif    // CONFIG_VP9_HIGHBITDEPTH
+
+#ifdef __cplusplus
+}  // extern "C"
+#endif
+
 #endif    // VP9_ENCODER_VP9_RESIZE_H_