Merge branch 'jk/write-in-full-fix'

Many codepaths did not diagnose write failures correctly when disks
go full, due to their misuse of write_in_full() helper function,
which have been corrected.

* jk/write-in-full-fix:
  read_pack_header: handle signed/unsigned comparison in read result
  config: flip return value of store_write_*()
  notes-merge: use ssize_t for write_in_full() return value
  pkt-line: check write_in_full() errors against "< 0"
  convert less-trivial versions of "write_in_full() != len"
  avoid "write_in_full(fd, buf, len) != len" pattern
  get-tar-commit-id: check write_in_full() return against 0
  config: avoid "write_in_full(fd, buf, len) < len" pattern

streaming.c

@@ -540,7 +540,7 @@ int stream_blob_to_fd(int fd, const struct object_id *oid, struct stream_filter
 			kept = 0;
 		wrote = write_in_full(fd, buf, readlen);
 
-		if (wrote != readlen)
+		if (wrote < 0)
 			goto close_and_exit;
 	}
 	if (kept && (lseek(fd, kept - 1, SEEK_CUR) == (off_t) -1 ||