sdiff: Fix binary case.

MFC after: 1 week
Sponsored by: Klara, Inc.
Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D43942

sdiff: Fix --expand-tabs and --tabsize.

MFC after: 1 week
Sponsored by: Klara, Inc.
Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D43941

sdiff: Misc cleanup.

MFC after: 1 week
Sponsored by: Klara, Inc.
Reviewed by: markj
Differential Revision: https://reviews.freebsd.org/D43943

usr.bin: Automated cleanup of cdefs and other formatting

Apply the following automated changes to try to eliminate
no-longer-needed sys/cdefs.h includes as well as now-empty
blank lines in a row.

Remove /^#if.*\n#endif.*\n#include\s+<sys/cdefs.h>.*\n/
Remove /\n+#include\s+<sys/cdefs.h>.*\n+#if.*\n#endif.*\n+/
Remove /\n+#if.*\n#endif.*\n+/
Remove /^#if.*\n#endif.*\n/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/types.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/param.h>/
Remove /\n+#include\s+<sys/cdefs.h>\n#include\s+<sys/capsicum.h>/

Sponsored by: Netflix

Remove $FreeBSD$: one-line .c pattern

Remove /^[\s*]*__FBSDID\("\$FreeBSD\$"\);?\s*\n/

Rename variables confusing gcc 4.2.1

While there is no reason it shadows div(3) gcc 4.2.1 complains about it

MFC after: 1 week

Fix -Wincompatible-pointer-types-discards-qualifiers warnings

MFC after: 1 week

Remove a useless loop over the long options before passing through some
options to diff(1)

When passingthrough from sdiff to diff the -H/--speed-large-files
options rename it to the long version as GNU diff only support the long
version of the option not the short version

Remove extra entries from the option enum

MFC after: 3 days

Make sdiff --left-column work as expected

MFC after: 3 days

Fix typos in sdiff(1) message and improve display

Remove the common.h include which is actually not used in sdiff.c

Remove reference of z(s)diff which was dropped before importing

sdiff: improve errx string

errx() appends a newline so \n is superfluous. Also switch to lower case
with no period for consistency with other errx strings.

sdiff: remove non finish/function code

2 extra options not available neither on other BSD nor in GNU sdiff:
--diff-pid and --pipe-fd were present in the SoC code, none were usable

Just remove it

Remove usage of _WITH_GETLINE from usr.bin

sdiff(1): Fix potential NULL deref in cleanup path

In the presence of the --diff-pid argument, it is possible for 'diffpipe' to be
NULL. Only fclose() it if it was initialized.

Reported by: Coverity
CID: 1355183
Sponsored by: EMC / Isilon Storage Division

Replace fparseln(3) with getline(3)

It removes a dependency on libutil.

fgetc returns an int not a char.

Found by: powerpc builds failing due to comparing with EOF raised:
"comparison is always false due to limited range of data type"

When checking for binary file, check if ch is not EOF only ch actually got
a value assigned

Reported by: pfg

import sdiff(1) from GSoC 2012

Import sdiff(1) from the diff version written by Raymond Lai,
improved during GSoC 2012 by Jesse Hagewood.

Compared to the version done in during that summer of code:
- Remove the zlib frontend: zsdiff
- Compatible output (column size and separators) with GNU sdiff

Compared to GNU sdiff in ports:
- The only difference is padding using spaces vs tabs

Compared to OpenBSD and NetBSD import:
- Implement missing options (including long options) from GNU sdiff
- Improved support for the edition mode (signal handling)
- Output visually compatible with GNU sdiff: size of columns

While here import regression tests from NetBSD adapted to fit the output as
expected by GNU sdiff

Reviewed by: emaste (in part)
Obtained from: OpenBSD, NetBSD, GSoC 2012
Relnotes: yes
Differential Revision: https://reviews.freebsd.org/D5981
Differential Revision: https://reviews.freebsd.org/D6032 (diff with NetBSD version)
Differential Revision: https://reviews.freebsd.org/D6033 (diff with OpenBSD version)