In fact, this is not a good decission, writer is a better place for
writer dependent data, but for now I prefer to store anything in the
target. Later we can improve Writer encapsulation.
At this time, nglibisofs is able to output an image!! Note that communication
between writer and read thread is done via a pipe. That will be replaced by a
ring buffer in the near future.
This only adds the tree creation functions, no sorting and name mangling
yet. Only plain ECMA-119 supported for now, nor RR, relaxed
restrictions, etc..
This also adds a little test program.
It happens that tsearch seems to not return a pointer to the inserted element,
but a pointer to a pointer to the inserted element (that makes sense, as we
are inserted pointers...). This bug, thus, was related to a wrong
understanding of the tsearch API!
Ecma119Image, defined for first time in this commit, is the context for image
written. It keeps the low level objects needed during image written.
IsoFileSrc is the low level object that takes care about the info needed to
write file contents to image. It takes care about reading from Stream in 2K
block chunks. To prevent the same file be written twice to image, we keep in
Ecma119Image a search tree, indexed by the triple key (fs, device, inode) that
uniquelly identifies a source.
