blob: 8694575e51381f26ba91290449c26ca7db0636af [file] [log] [blame]
/*
* 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.
*/
#include <string.h>
#include "MtpDataPacket.h"
#include "MtpStringBuffer.h"
namespace android {
MtpStringBuffer::MtpStringBuffer()
: mCharCount(0),
mByteCount(1)
{
mBuffer[0] = 0;
}
MtpStringBuffer::MtpStringBuffer(const char* 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) {
int 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::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);
// 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);
}
}
} // namespace android