MFC r356723-r356725, r357649, r357652: diff(1) catch-up

2020-04-27T22:33:32Z

r356723: mkstemp returns -1 r356724: asprintf returns -1, not an arbitrary value < 0. Also upon error the (very sloppy specification) leaves an undefined value in *ret, so it is wrong to inspect it, the error condition is enough. r356725: When system calls indicate an error they return -1, not some arbitrary value < 0. errno is only updated in this case. r357649: Update diff(1) TODO removing what has been implemented r357652: Fix most of the style warnings

Import diff from OpenBSD and remove GNU diff

2017-03-11T05:01:29Z

Some of the modifications from the previous summer of code has been integrated Modification for compatibility with GNU diff output has been added Main difference with OpenBSD: Implement multiple GNU diff options: * --ignore-file-name-case * --no-ignore-file-name-case * --normal * --tabsize * --strip-trailing-cr Make diff -p compatible with GNU diff Implement diff -l Make diff -r compatible with GNU diff Capsicumize diffing 2 regular files Add a simple test suite Approved by: AsiaBSDcon devsummit Obtained from: OpenBSD, GSoC Relnotes: yes

src/usr.bin/diff/xmalloc.c, branch releng/12.2

MFC r356723-r356725, r357649, r357652: diff(1) catch-up

Import diff from OpenBSD and remove GNU diff