this is not a conformance issue as posix does not specify the
argument order, but the order is specified for bsearch and some
systems document the order for lsearch consistently (openbsd).
since there were two indpendent reports of this issue it's better
to use the more widely expected argument order.
the tsearch data structure is an avl tree, but it did not implement
the deletion operation correctly so the tree could become unbalanced.
reported by Ed Schouten.
There are two changes here, both of which make sense to be done in a
single patch:
- Remove hash from struct elem and compute it at runtime wherever
necessary.
- Eliminate struct elem and use ENTRY directly.
As a result we cut down on the memory usage as each element in the
hash table now contains only an ENTRY not an ENTRY + size_t for the
hash. The downside is that the hash needs to be computed at runtime.
the size and alignment of struct hsearch_data are matched to the glibc
definition for binary compatibility. the members of the structure do
not match, which should not be a problem as long as applications
correctly treat the structure as opaque.
unlike the glibc implementation, this version of hcreate_r does not
require the caller to zero-fill the structure before use.
patch by nsz. the actual object the caller has storing the tree root
has type void *, so accessing it as struct node * is not valid.
instead, simply access the value, move it to a temporary of the
appropriate type and work from there, then move the result back.
