camera2 vndk: Add ACameraMananger_getTagFromName.

In some situations, clients of the vndk might need to be able to query
tags at runtime, based on tag names. For example, when client hals are
de-coupled from the camera HAL.

Bug: 131093919

Test: AImageReaderVendorTest
Test: Modify AImageReaderVendorTest to retrieve vendor tags given their
      names, using ACameraMetadata_getTagFromName

Change-Id: I1cdec5b154037185e99d29be2c6890e4fdc4a32a
Signed-off-by: Jayant Chowdhary <jchowdhary@google.com>

camera/ndk/Android.bp

@@ -64,6 +64,10 @@ cc_library_shared {
         "-Wextra",
         "-Werror",
     ],
+    // TODO: jchowdhary@, use header_libs instead b/131165718
+    include_dirs: [
+        "system/media/private/camera/include",
+    ],
     export_include_dirs: ["include"],
     export_shared_lib_headers: [
         "libnativewindow",
@@ -123,6 +127,10 @@ cc_library_shared {
         "android.hardware.camera.common@1.0-helper",
         "libarect",
     ],
+    // TODO: jchowdhary@, use header_libs instead b/131165718
+    include_dirs: [
+        "system/media/private/camera/include",
+    ],
     product_variables: {
         pdk: {
             enabled: false,

camera/ndk/NdkCameraManager.cpp

@@ -190,3 +190,17 @@ camera_status_t ACameraManager_openCamera(
     }
     return mgr->openCamera(cameraId, callback, device);
 }
+
+#ifdef __ANDROID_VNDK__
+EXPORT
+camera_status_t ACameraManager_getTagFromName(ACameraManager *mgr, const char* cameraId,
+        const char *name, /*out*/uint32_t *tag) {
+    ATRACE_CALL();
+    if (mgr == nullptr || cameraId == nullptr || name == nullptr) {
+        ALOGE("%s: invalid argument! mgr %p cameraId %p name %p",
+                __FUNCTION__, mgr, cameraId, name);
+        return ACAMERA_ERROR_INVALID_PARAMETER;
+    }
+    return mgr->getTagFromName(cameraId, name, tag);
+}
+#endif

camera/ndk/include/camera/NdkCameraManager.h

@@ -374,6 +374,23 @@ camera_status_t ACameraManager_unregisterExtendedAvailabilityCallback(
         ACameraManager* manager,
         const ACameraManager_ExtendedAvailabilityCallbacks* callback) __INTRODUCED_IN(29);
 
+#ifdef __ANDROID_VNDK__
+/**
+ * Retrieve the tag value, given the tag name and camera id.
+ * This method is device specific since some metadata might be defined by device manufacturers
+ * and might only be accessible for specific cameras.
+ * @param manager The {@link ACameraManager} of interest.
+ * @param cameraId The cameraId, which is used to query camera characteristics.
+ * @param name The name of the tag being queried.
+ * @param tag The output tag assigned by this method.
+ *
+ * @return ACAMERA_OK only if the function call was successful.
+ */
+camera_status_t ACameraManager_getTagFromName(ACameraManager *manager, const char* cameraId,
+        const char *name, /*out*/uint32_t *tag)
+        __INTRODUCED_IN(29);
+#endif
+
 #endif /* __ANDROID_API__ >= 29 */
 
 __END_DECLS

camera/ndk/ndk_vendor/impl/ACameraManager.cpp

@@ -22,6 +22,8 @@
 #include "ACameraMetadata.h"
 #include "ndk_vendor/impl/ACameraDevice.h"
 #include "utils.h"
+#include <CameraMetadata.h>
+#include <camera_metadata_hidden.h>
 
 #include <utils/Vector.h>
 #include <cutils/properties.h>
@@ -587,6 +589,26 @@ ACameraManager::openCamera(
     return ACAMERA_OK;
 }
 
+camera_status_t
+ACameraManager::getTagFromName(const char *cameraId, const char *name, uint32_t *tag) {
+    sp<ACameraMetadata> rawChars;
+    camera_status_t ret = getCameraCharacteristics(cameraId, &rawChars);
+    if (ret != ACAMERA_OK) {
+        ALOGE("%s, Cannot retrieve camera characteristics for camera id %s", __FUNCTION__,
+                cameraId);
+        return ACAMERA_ERROR_METADATA_NOT_FOUND;
+    }
+    const CameraMetadata& metadata = rawChars->getInternalData();
+    const camera_metadata_t *rawMetadata = metadata.getAndLock();
+    metadata_vendor_id_t vendorTagId = get_camera_metadata_vendor_id(rawMetadata);
+    metadata.unlock(rawMetadata);
+    sp<VendorTagDescriptorCache> vtCache = VendorTagDescriptorCache::getGlobalVendorTagCache();
+    sp<VendorTagDescriptor> vTags = nullptr;
+    vtCache->getVendorTagDescriptor(vendorTagId, &vTags);
+    status_t status= metadata.getTagFromName(name, vTags.get(), tag);
+    return status == OK ? ACAMERA_OK : ACAMERA_ERROR_METADATA_NOT_FOUND;
+}
+
 ACameraManager::~ACameraManager() {
 
 }

camera/ndk/ndk_vendor/impl/ACameraManager.h

@@ -204,6 +204,7 @@ struct ACameraManager {
     camera_status_t openCamera(const char* cameraId,
                                ACameraDevice_StateCallbacks* callback,
                                /*out*/ACameraDevice** device);
+    camera_status_t getTagFromName(const char *cameraId, const char *name, uint32_t *tag);
 
   private:
     enum {

camera/ndk/ndk_vendor/tests/AImageReaderVendorTest.cpp

@@ -799,6 +799,15 @@ TEST_F(AImageReaderVendorTest, CreateWindowNativeHandle) {
     bool isBC = isCapabilitySupported(staticMetadata,
             ACAMERA_REQUEST_AVAILABLE_CAPABILITIES_BACKWARD_COMPATIBLE);
 
+    uint32_t namedTag = 0;
+    // Test that ACameraMetadata_getTagFromName works as expected for public tag
+    // names
+    camera_status_t status = ACameraManager_getTagFromName(mCameraManager, cameraId,
+            "android.control.aeMode", &namedTag);
+
+    ASSERT_EQ(status, ACAMERA_OK);
+    ASSERT_EQ(namedTag, ACAMERA_CONTROL_AE_MODE);
+
     ACameraMetadata_free(staticMetadata);
 
     if (!isBC) {