Function changeFieldSplitLine

samblaster.cpp:297–326

Change a field into a value. This will be tough given how we output lines. So, we might have to try a few things. Start with simply expanding/contracting the string to put in the new value.

// So, we might have to try a few things.
// Start with simply expanding/contracting the string to put in the new value.
void changeFieldSplitLine(splitLine_t * line, int fnum, char * newValue)
{
    // What we do will depend on the lengths of the two strings.
    // So, start by calculaing these only once.
    char * fp = line->fields[fnum];
    int oldLen = strlen(fp);
    int newLen = strlen(newValue);
    // Now see if we need to first change the length of the whole line.
    int move = newLen - oldLen;
    if (move != 0)
    {
        // This should never happen, but to be robust we need to check.
        // It is messy to fix it, as all the field ptrs will now be wrong.
        if ((size_t)(line->bufLen + move) >= line->maxBufLen)
        {
            resizeSplitLine(line, line->bufLen + move);
            fp = line->fields[fnum];
        }
        // Calculate the size of the tail that is still needed.
        int distance = 1 + line->bufLen - (fp - line->buffer) - oldLen;
        // Do the copy.
        memmove(fp+newLen, fp+oldLen, distance);
        // Correct the total length of the buffer.
        line->bufLen += move;
        // We need to correct the other ptrs as well.
        for (int i=fnum+1; i<line->numFields; i++) line->fields[i] += move;
    }
    // Copy in the new value.
    memcpy(fp, newValue, newLen);
}

void addTag(splitLine_t * line, const char * header, const char * val)
{