[Audacity-devel] WaveTrack.cpp - Nitpick

[<bf...@ew...>]

I'm just looking at 'WaveTrack.cpp' to see whether I can reduce the 
number of warnings (currently 61).

One of the first things that I note is 

    int WaveTrack::sMaxDiskBlockSize = 1048576;   /* 0x00100000 */

From its value this is clearly the maximum count of blocks
on a disk to be used for some purpose (rather than the size
of a block), and there is no indication that it is constant,
so perhaps it isn't.

More to the point, the C++ language, like C before it, only 
guarantees 16 bits for an int.

There is a well defined size type for C, which is defined as

   "The type size_t is the unsigned integral type produced by the sizeof 
    operator."

In effect, size_t is the maximum size (count of items) of an array
in C and a useful measure of the reach of a pointer. It is (and
this is of direct relevance) the return type of fread and fwrite,
being used precisely to size a disk by its count of blocks. I
would guess that the designers of Audacity reasoned that it was
likely to produse large files, and that it important not to
break the underlying file system by trying to create files
of more than a million or so blocks

Some people are not happy using naked ints in production code
in the first place (int should be reserved for those cases
where its efficiency is important); and I would suggest that
this value should be stored as size_t .

This may be completely unacceptable if it must be a signed type.
(Under ANSI C size_t is guaranteed to be unsigned), in which case I would
suggest defining our own type for count of blocks, offsets et cetera:

    /* Type for holding count of blocks in a sound file */
    typedef IndexBlock signed long int;

thus it could be just as easily defined as something else, if
it was thought to have been a mistake.

On my system wxWindows actually does define the 32-bit integral
types as ints, but then my compiler uses 32 bit ints.

Any thoughts?

Ben