So far, when outputing information about copy progress we'd suppress the
digit after the dot if it is zero. That makes the progress bar a bit
"jumpy", because sometimes there are two more character cells used than
other times. Let's just always output one digit after the dot here
hence, to avoid this.
This makes output a bit shorter and nicer. For us, shorter output is generally
better.
Also, drop unnecessary UINT64_C macros. The left operand is always uint64_t,
and C upcasting rules mean that it doesn't matter if the right operand is
narrower or signed, the operation is always done on the wider unsigned type.
Also,
- drop unnecessary +1 from buffer size, as IF_NAMESIZE or IFNAMSIZ
includes the nul at the end.
- format_ifname() does not update buffer on failure,
- introduces format_ifname_alloc(), FORMAT_IFNAME(), and their friends.
According to Coverity, 194 ouf of 227 times we check for snprintf return code.
Voidify the rest.
CID#1461512
CID#1461513
CID#1461514
CID#1461515
CID#1461516
CID#1461518
CID#1461519
CID#1461520
CID#1461522
