Safety in populating a QByteArray by it's data pointer.

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C++

QT

Hi All,

I'm curious as to whether it is safe to pass the data pointer of a QByteArray that has been properly resized, to a C function that will populate the memory within it.

I am thinking that it shouldn't be a problem, but I feel kinda gross doing it.

SpeexBits bits;
void *dec_state;
int bufferPosition = 0;
const int SAMPLES_PER_SEC = 32000;
const int BUFFER_LEN_SECONDS = 5;
const int FRAME_SIZE_BYTES = SAMPLES_PER_SEC / (1000 / 20) * sizeof(int16_t);

QByteArray outBuf;
outBuf.resize(SAMPLES_PER_SEC * sizeof(int16_t) * BUFFER_LEN_SECONDS);

...

QByteArray inBuf((const char*)msg->payload, msg->size);
speex_bits_read_from(&bits, inBuf.data(), inBuf.size());
speex_decode_int(dec_state, &bits, outBuf.data() + bufferPosition);
bufferPosition += FRAME_SIZE_BYTES;

...

<playback>

Though I think this should work, it doesn't feel right, however, I don't want to make multiple copies of the data for no other reason than to populate the QByteArray safely. So I guess my question is, can I safely do this? Is this the recommended way to populate a QByteArray from a function? Is there a better way that doesn't require multiple copies of the data?