Camera2: Use CameraMetadata wrapper class.
Wrap the use of the camera_metadata library inside a CameraMetadata
class to avoid memory leaks, improve code clarity, and increase type
safety.
Bug: 6243944
Change-Id: I90ca592b5875e27e4c58ea1ca680582dc3c3b56a
diff --git a/services/camera/libcameraservice/CameraMetadata.h b/services/camera/libcameraservice/CameraMetadata.h
new file mode 100644
index 0000000..afb8318
--- /dev/null
+++ b/services/camera/libcameraservice/CameraMetadata.h
@@ -0,0 +1,166 @@
+/*
+ * Copyright (C) 2012 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef ANDROID_SERVERS_CAMERA_METADATA_CPP
+#define ANDROID_SERVERS_CAMERA_METADATA_CPP
+
+#include "system/camera_metadata.h"
+#include <utils/String8.h>
+#include <utils/Vector.h>
+
+namespace android {
+
+/**
+ * A convenience wrapper around the C-based camera_metadata_t library.
+ */
+class CameraMetadata {
+ public:
+ /** Creates an empty object; best used when expecting to acquire contents
+ * from elsewhere */
+ CameraMetadata();
+ /** Creates an object with space for entryCapacity entries, with
+ * dataCapacity extra storage */
+ CameraMetadata(size_t entryCapacity, size_t dataCapacity = 10);
+
+ ~CameraMetadata();
+
+ /** Takes ownership of passed-in buffer */
+ CameraMetadata(camera_metadata_t *buffer);
+ /** Clones the metadata */
+ CameraMetadata(const CameraMetadata &other);
+
+ /**
+ * Assignment clones metadata buffer.
+ */
+ CameraMetadata &operator=(const CameraMetadata &other);
+ CameraMetadata &operator=(const camera_metadata_t *buffer);
+
+ /**
+ * Release a raw metadata buffer to the caller. After this call,
+ * CameraMetadata no longer references the buffer, and the caller takes
+ * responsibility for freeing the raw metadata buffer (using
+ * free_camera_metadata()), or for handing it to another CameraMetadata
+ * instance.
+ */
+ camera_metadata_t* release();
+
+ /**
+ * Clear the metadata buffer and free all storage used by it
+ */
+ void clear();
+
+ /**
+ * Acquire a raw metadata buffer from the caller. After this call,
+ * the caller no longer owns the raw buffer, and must not free or manipulate it.
+ * If CameraMetadata already contains metadata, it is freed.
+ */
+ void acquire(camera_metadata_t* buffer);
+
+ /**
+ * Acquires raw buffer from other CameraMetadata object. After the call, the argument
+ * object no longer has any metadata.
+ */
+ void acquire(CameraMetadata &other);
+
+ /**
+ * Append metadata from another CameraMetadata object.
+ */
+ status_t append(const CameraMetadata &other);
+
+ /**
+ * Number of metadata entries.
+ */
+ size_t entryCount() const;
+
+ /**
+ * Sort metadata buffer for faster find
+ */
+ status_t sort();
+
+ /**
+ * Update metadata entry. Will create entry if it doesn't exist already, and
+ * will reallocate the buffer if insufficient space exists. Overloaded for
+ * the various types of valid data.
+ */
+ status_t update(uint32_t tag,
+ const uint8_t *data, size_t data_count);
+ status_t update(uint32_t tag,
+ const int32_t *data, size_t data_count);
+ status_t update(uint32_t tag,
+ const float *data, size_t data_count);
+ status_t update(uint32_t tag,
+ const int64_t *data, size_t data_count);
+ status_t update(uint32_t tag,
+ const double *data, size_t data_count);
+ status_t update(uint32_t tag,
+ const camera_metadata_rational_t *data, size_t data_count);
+ status_t update(uint32_t tag,
+ const String8 &string);
+
+ template<typename T>
+ status_t update(uint32_t tag, Vector<T> data) {
+ return update(tag, data.array(), data.size());
+ }
+
+ /**
+ * Get metadata entry by tag id
+ */
+ camera_metadata_entry find(uint32_t tag);
+
+ /**
+ * Get metadata entry by tag id, with no editing
+ */
+ camera_metadata_ro_entry find(uint32_t tag) const;
+
+ /**
+ * Delete metadata entry by tag
+ */
+ status_t erase(uint32_t tag);
+
+ /**
+ * Dump contents into FD for debugging. The verbosity levels are
+ * 0: Tag entry information only, no data values
+ * 1: Level 0 plus at most 16 data values per entry
+ * 2: All information
+ *
+ * The indentation parameter sets the number of spaces to add to the start
+ * each line of output.
+ */
+ void dump(int fd, int verbosity = 1, int indentation = 0) const;
+
+ private:
+ camera_metadata_t *mBuffer;
+
+ /**
+ * Check if tag has a given type
+ */
+ status_t checkType(uint32_t tag, uint8_t expectedType);
+
+ /**
+ * Base update entry method
+ */
+ status_t update(uint32_t tag, const void *data, size_t data_count);
+
+ /**
+ * Resize metadata buffer if needed by reallocating it and copying it over.
+ */
+ status_t resizeIfNeeded(size_t extraEntries, size_t extraData);
+
+};
+
+}; // namespace android
+
+#endif