commit d8fccf0124b78230ae2071fecc6bc6aebe8c540c
author Kevin Schoedel <kpschoedel@google.com> Mon Jun 05 11:13:20 2017 -0400
committer Kevin Schoedel <kpschoedel@google.com> Tue Jun 06 12:34:39 2017 -0400
tree f6f70495cff1bce472736d57a68bf6bb331bd3aa
parent cf61460126ff0f945e27171f241b800b21bb160e

Add DVR API for scroll event injection.

Bug: 62226675
Test: manual, vrcore build
Change-Id: Ic7d329eba8003b0e294b3a11a83ed5f868b801f8

libs/vr/libdvr/dvr_api.cpp

diff --git a/libs/vr/libdvr/dvr_api.cpp b/libs/vr/libdvr/dvr_api.cpp
index 5f35dcf..dc31917 100644
--- a/libs/vr/libdvr/dvr_api.cpp
+++ b/libs/vr/libdvr/dvr_api.cpp
@@ -3,6 +3,8 @@
 #include <errno.h>
 #include <utils/Log.h>
 
+#include <algorithm>
+
 // Headers from libdvr
 #include <dvr/dvr_buffer.h>
 #include <dvr/dvr_buffer_queue.h>
@@ -23,15 +25,20 @@
   ALOGI("dvrGetApi: api=%p struct_size=%zu version=%d", api, struct_size,
         version);
   if (version == 1) {
-    if (struct_size != sizeof(DvrApi_v1)) {
-      ALOGE("dvrGetApi: Size mismatch: expected %zu; actual %zu",
-            sizeof(DvrApi_v1), struct_size);
-      return -EINVAL;
-    }
+    // New entry points are added at the end. If the caller's struct and
+    // this library have different sizes, we define the entry points in common.
+    // The caller is expected to handle unset entry points if necessary.
+    size_t clamped_struct_size = std::min(struct_size, sizeof(DvrApi_v1));
     DvrApi_v1* dvr_api = static_cast<DvrApi_v1*>(api);
 
 // Defines an API entry for V1 (no version suffix).
-#define DVR_V1_API_ENTRY(name) dvr_api->name = dvr##name
+#define DVR_V1_API_ENTRY(name)                                 \
+  do {                                                         \
+    if ((offsetof(DvrApi_v1, name) + sizeof(dvr_api->name)) <= \
+        clamped_struct_size) {                                 \
+      dvr_api->name = dvr##name;                               \
+    }                                                          \
+  } while (0)
 
 #include "include/dvr/dvr_api_entries.h"
 

libs/vr/libdvr/include/dvr/dvr_api.h

diff --git a/libs/vr/libdvr/include/dvr/dvr_api.h b/libs/vr/libdvr/include/dvr/dvr_api.h
index 0c10907..4693c7f 100644
--- a/libs/vr/libdvr/include/dvr/dvr_api.h
+++ b/libs/vr/libdvr/include/dvr/dvr_api.h
@@ -238,6 +238,8 @@
                                           float pressure);
 typedef int (*DvrVirtualTouchpadButtonStatePtr)(DvrVirtualTouchpad* client,
                                                 int touchpad, int buttons);
+typedef int (*DvrVirtualTouchpadScrollPtr)(DvrVirtualTouchpad* client,
+                                           int touchpad, float x, float y);
 
 // dvr_hardware_composer_client.h
 typedef struct DvrHwcClient DvrHwcClient;

libs/vr/libdvr/include/dvr/dvr_api_entries.h

diff --git a/libs/vr/libdvr/include/dvr/dvr_api_entries.h b/libs/vr/libdvr/include/dvr/dvr_api_entries.h
index 802a0f7..ae5ef18 100644
--- a/libs/vr/libdvr/include/dvr/dvr_api_entries.h
+++ b/libs/vr/libdvr/include/dvr/dvr_api_entries.h
@@ -141,3 +141,9 @@
 DVR_V1_API_ENTRY(HwcFrameGetLayerVisibleRegion);
 DVR_V1_API_ENTRY(HwcFrameGetLayerNumDamagedRegions);
 DVR_V1_API_ENTRY(HwcFrameGetLayerDamagedRegion);
+
+// New entries added at the end to allow the DVR platform library API
+// to be updated before updating VrCore.
+
+// Virtual touchpad client
+DVR_V1_API_ENTRY(VirtualTouchpadScroll);