[CRIU] [PATCH 0/7] New helpers for easy string construction

[Stanislav Kinsburskiy]

This patch set introduced new helpers add_to_string() and construct_string(),
which can be used to create or add to string a variable amount of parameters
in the way, like sprintf does, but including allocation of sufficient buffer
size.
They can be used instead of manual rellocation of some string for
concatenation or explicit allocation and printing.
This patch set (except the first one, introducing helpers) replaces only
realloc() calls and alloc()+sprintf() call, and reduces code base
for 37 lines wth improving it's readability.