add mtp responder to TWRP.

Big thanks to Dees_Troy for helping with the implementation.

Change-Id: I6c9c522b9c9de5dc139e2ecb0141008182ba07f0

mtp/MtpStringBuffer.cpp

@@ -0,0 +1,167 @@
+/*
+ * Copyright (C) 2010 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.
+ *
+ * Copyright (C) 2014 TeamWin - bigbiff and Dees_Troy mtp database conversion to C++
+ */
+
+#include <string.h>
+#include "MtpDataPacket.h"
+#include "MtpStringBuffer.h"
+
+MtpStringBuffer::MtpStringBuffer()
+	:	mCharCount(0),
+		mByteCount(1)
+{
+	mBuffer[0] = 0;
+}
+
+MtpStringBuffer::MtpStringBuffer(const char* src)
+	:	mCharCount(0),
+		mByteCount(1)
+{
+	set(src);
+}
+
+MtpStringBuffer::MtpStringBuffer(const uint16_t* src)
+	:	mCharCount(0),
+		mByteCount(1)
+{
+	set(src);
+}
+
+MtpStringBuffer::MtpStringBuffer(const MtpStringBuffer& src)
+	:   mCharCount(src.mCharCount),
+		mByteCount(src.mByteCount)
+{
+	memcpy(mBuffer, src.mBuffer, mByteCount);
+}
+
+
+MtpStringBuffer::~MtpStringBuffer() {
+}
+
+void MtpStringBuffer::set(const char* src) {
+	size_t length = strlen(src);
+	if (length >= sizeof(mBuffer))
+		length = sizeof(mBuffer) - 1;
+	memcpy(mBuffer, src, length);
+
+	// count the characters
+	int count = 0;
+	char ch;
+	while ((ch = *src++) != 0) {
+		if ((ch & 0x80) == 0) {
+			// single byte character
+		} else if ((ch & 0xE0) == 0xC0) {
+			// two byte character
+			if (! *src++) {
+				// last character was truncated, so ignore last byte
+				length--;
+				break;
+			}
+		} else if ((ch & 0xF0) == 0xE0) {
+			// 3 byte char
+			if (! *src++) {
+				// last character was truncated, so ignore last byte
+				length--;
+				break;
+			}
+			if (! *src++) {
+				// last character was truncated, so ignore last two bytes
+				length -= 2;
+				break;
+			}
+		}
+		count++;
+	}
+
+	mByteCount = length + 1;
+	mBuffer[length] = 0;
+	mCharCount = count;
+}
+
+void MtpStringBuffer::set(const uint16_t* src) {
+	int count = 0;
+	uint16_t ch;
+	uint8_t* dest = mBuffer;
+
+	while ((ch = *src++) != 0 && count < 255) {
+		if (ch >= 0x0800) {
+			*dest++ = (uint8_t)(0xE0 | (ch >> 12));
+			*dest++ = (uint8_t)(0x80 | ((ch >> 6) & 0x3F));
+			*dest++ = (uint8_t)(0x80 | (ch & 0x3F));
+		} else if (ch >= 0x80) {
+			*dest++ = (uint8_t)(0xC0 | (ch >> 6));
+			*dest++ = (uint8_t)(0x80 | (ch & 0x3F));
+		} else {
+			*dest++ = ch;
+		}
+		count++;
+	}
+	*dest++ = 0;
+	mCharCount = count;
+	mByteCount = dest - mBuffer;
+}
+
+void MtpStringBuffer::readFromPacket(MtpDataPacket* packet) {
+	int count = packet->getUInt8();
+	uint8_t* dest = mBuffer;
+	for (int i = 0; i < count; i++) {
+		uint16_t ch = packet->getUInt16();
+		if (ch >= 0x0800) {
+			*dest++ = (uint8_t)(0xE0 | (ch >> 12));
+			*dest++ = (uint8_t)(0x80 | ((ch >> 6) & 0x3F));
+			*dest++ = (uint8_t)(0x80 | (ch & 0x3F));
+		} else if (ch >= 0x80) {
+			*dest++ = (uint8_t)(0xC0 | (ch >> 6));
+			*dest++ = (uint8_t)(0x80 | (ch & 0x3F));
+		} else {
+			*dest++ = ch;
+		}
+	}
+	*dest++ = 0;
+	mCharCount = count;
+	mByteCount = dest - mBuffer;
+}
+
+void MtpStringBuffer::writeToPacket(MtpDataPacket* packet) const {
+	int count = mCharCount;
+	const uint8_t* src = mBuffer;
+	packet->putUInt8(count > 0 ? count + 1 : 0);
+
+	// expand utf8 to 16 bit chars
+	for (int i = 0; i < count; i++) {
+		uint16_t ch;
+		uint16_t ch1 = *src++;
+		if ((ch1 & 0x80) == 0) {
+			// single byte character
+			ch = ch1;
+		} else if ((ch1 & 0xE0) == 0xC0) {
+			// two byte character
+			uint16_t ch2 = *src++;
+			ch = ((ch1 & 0x1F) << 6) | (ch2 & 0x3F);
+		} else {
+			// three byte character
+			uint16_t ch2 = *src++;
+			uint16_t ch3 = *src++;
+			ch = ((ch1 & 0x0F) << 12) | ((ch2 & 0x3F) << 6) | (ch3 & 0x3F);
+		}
+		packet->putUInt16(ch);
+	}
+	// only terminate with zero if string is not empty
+	if (count > 0)
+		packet->putUInt16(0);
+}
+