MTP: Use media provider database to implement MTP device support.

Uses a new "MTP objects" table in the media provider to support basic
enumeration of the external storage file system.
Support for accessing audio, video and image metadata in the existing
media provider tables will be added in a later commit.

The C++ MtpDatabase class is now abstract, to support a proxy subclass that
calls through JNI to the Java MtpDatabase class in the media provider.

Change-Id: I90f0db5f3acc5d35ae78c27a8507edff16d14305
Signed-off-by: Mike Lockwood <lockwood@android.com>

1 files changed, 15 insertions, 4 deletions

diff --git a/media/mtp/MtpDataPacket.cpp b/media/mtp/MtpDataPacket.cpp
index a7e975c..6f9ea24 100644
--- a/media/mtp/MtpDataPacket.cpp
+++ b/media/mtp/MtpDataPacket.cpp
@@ -299,17 +299,28 @@ void MtpDataPacket::putAUInt64(const uint64_t* values, int count) {
         putUInt64(*values++);
 }
 
-void MtpDataPacket::putString(const MtpStringBuffer& string)
-{
+void MtpDataPacket::putString(const MtpStringBuffer& string) {
     string.writeToPacket(this);
 }
 
-void MtpDataPacket::putString(const char* s)
-{
+void MtpDataPacket::putString(const char* s) {
     MtpStringBuffer string(s);
     string.writeToPacket(this);
 }
 
+void MtpDataPacket::putString(const uint16_t* string) {
+    int count = 0;
+    for (int i = 0; i < 256; i++) {
+        if (string[i])
+            count++;
+        else
+            break;
+    }
+    putUInt8(count);
+    for (int i = 0; i < count; i++)
+        putUInt16(string[i]);
+}
+
 #ifdef MTP_DEVICE 
 int MtpDataPacket::read(int fd) {
     // first read the header