guard MIN() macro against redefinition

provide functions to parse/serialize different hashes it abstracts over the hash type and ensures that object ids are zero'ed before their sha1 digest is written. Needed by the incoming sha256 support. ok stsp@

rename lib/sha1.c to lib/hash.c It will soon grow functions to deal with sha256 too. stsp@ agrees.

include sha2.h too where sha1.h is included In preparation for wide sha256 support; stsp@ agrees. Change done mechanically with find . -iname \*.[cy] -exec sam {} + X ,x/<sha1\.h>/i/\n#include <sha2.h>

got patch: handle the removal of binary files Diffs that remove binary files don't have hunks so got patch would skip over them, treating that part of the diff as "noise". Different programs outputs a slightly different diff for this kind of patches, but the "Binary files ... and /dev/null differ" is usually shown, so try to match it. The adedd regress test covers got diff, git diff, and OpenBSD' /usr/bin/diff. CVS diffs will currently fail because the guessed file name will be wrong. CVS prints the file name in the Index and RCS lines which got patch currently ignores, and shows an useless path in the "Binary files /tmp/cvs... and /dev/null differ" line. Discussed with and ok stsp@

use mkstemps(3) instead of mkstemp(3) for opening named temporary files Allows 'got commit' to use a ".diff" suffix for temporary diff files. ok op@

respect umask when creating or changing files and directories This behaviour is already documented in got-worktree(5) but wasn't actually implemented. ok stsp@

handle unlink(2) errors for mergepath, tmppath, and apath in apply_patch() ok op@

ensure got patch respects x-bit perms for new files Reported by stsp on IRC: got patch failed to set the x-bit for a new file despite got diff recording mode 755. Parse got and git diffs for this data and set file modes accordingly. Tweaked with hint from op. ok stsp@

locate_hunk: set mangled earlier for clarity suggested by stsp@; no functional change.

allow for ignore whitespaces when matching the hunk

got patch: add -c flag to apply at a specified commit it's useful for e.g. to apply old patches that weren't generated by `got diff' or git-diff(1) and so lacks the metadata needed for the 3-way merge. manpage improvements from and ok stsp@

simplify got_patch/apply_patch to call reverse_patch in one place once Current code is overly complex; it looks if the diff *might* use diff3 merge to postpone reverse_patch until we know for sure. Instead, just reverse_patch in apply_patch once we know if merge *is* used or not.

fix `got patch -R' when using diff3 merge `got patch -R' fails spectacularly when applied on a diff that contains the info of the original blob for the diff3 merge machinery since it tries to apply the reverse of the patch to the old blob. change it to run the patch (_not_ reversed) on the old blob and then swap the arguments to got_diff3_merge which gives us the correct reverse merge of the diff. while here add a test case too. reported by naddy, discussed with and ok stsp@

use got_privsep_flush_imsg instead of reinventing it ok stsp@