}
void ID3::removeUnsynchronization() {
- for (size_t i = 0; i + 1 < mSize; ++i) {
- if (mData[i] == 0xff && mData[i + 1] == 0x00) {
- memmove(&mData[i + 1], &mData[i + 2], mSize - i - 2);
- --mSize;
+
+ // This file has "unsynchronization", so we have to replace occurrences
+ // of 0xff 0x00 with just 0xff in order to get the real data.
+
+ size_t writeOffset = 1;
+ for (size_t readOffset = 1; readOffset < mSize; ++readOffset) {
+ if (mData[readOffset - 1] == 0xff && mData[readOffset] == 0x00) {
+ continue;
}
+ // Only move data if there's actually something to move.
+ // This handles the special case of the data being only [0xff, 0x00]
+ // which should be converted to just 0xff if unsynchronization is on.
+ mData[writeOffset++] = mData[readOffset];
}
+
+ if (writeOffset < mSize) {
+ mSize = writeOffset;
+ }
+
}
static void WriteSyncsafeInteger(uint8_t *dst, size_t x) {