Re: [HACKERS] pg_dump, and strings

"Ansley, Michael" <Michael.Ansley@intec.co.za> writes:
> In pg_dump there is a file called common.c.  This file has some string
> handling routines in it that return a pointer to a fixed-length, static
> string (char *).  I need to remove the fixed-length bit (besides the fact
> fact that this is horrendously un-threadsafe).  So, what is the best
> mechanism to use on replacement?  There seem to be two fairly standard
> methods to use, a) make the calling function allocate the memory it
> requires, and pass that in to the called function, or b) the called function
> allocates memory using a documented call (say, malloc), and hands
> responsibility for freeing the memory to the calling function.  Given the
> non-fixed-length constraint, the second option would appear better, but does
> any body out there have any other ideas?

The first approach requires that the caller know in advance how much
result space the callee will need; unless the return type is fixed-size
that's usually a bad design.

Another possibility is to do something like the backend's palloc()
stuff, wherein responsibility for eventually cleaning up the garbage
is handed to a third party.  But that's probably overkill for pg_dump.
        regards, tom lane