patch: unsign the line length to avoid overflows.
Patch(1) uses a short int for the line length, which is usually
sufficient for regular diffs, but makes no effort to signal
when there is an overflow.
Change the line length to an unsigned short int to better use
the fact that a length is never negative. The change is loosely
inspired on a related change in DragonFly, but we avoid spending
more memory than necessary.
While here adjust the messages to be clearer on what is happening.
- Remove $DragonFly$ tags as they are using git nowadays and VCS tags will
not help merging.
- Other changes to Copyright headers to make them consistent with other
source code, we intend to fork from this point.
Reviewed by: pfg
DragonflyBSD and install it as bsdpatch. WITH_BSD_PATCH makes it
default and installs GNU patch as gnupatch.
Submitted by: pfg
Obtained from: The DragonflyBSD Project
