breaking out of the switch-case when l==-1 means the conditional below
will necessarily be true (-1 >= buf_size, a size_t variable) and the
function will return 0. it is, however, somewhat unclear that that's
what's happening. simply returning there is simpler
these are linux specific constants. glibc exposes them behind
_GNU_SOURCE, but, since SEEK_* is reserved for the implementation, we
can simply define them. furthermore, since they can't be used with
fseek() and other functions that deal with FILE, we don't add them to
stdio.h.
we make qsort a wrapper by providing a wrapper_cmp function that uses
the extra argument as a function pointer. should be optimized to a tail
call on most architectures, as long as it's built with
-fomit-frame-pointer, so the performance impact should be minimal.
to keep the git history clean, for now qsort_r is implemented in qsort.c
and qsort is implemented in qsort_nr.c. qsort.c also received a few
trivial cleanups, including replacing (*cmp)() calls with cmp().
qsort_nr.c contains only wrapper_cmp and qsort as a qsort_r wrapper
itself.
len is unsigned and can never be smaller than 0. though unlikely, an
error in read() would have lead to an out of bounds write to name.
Reported-by: Michael Forney <[email protected]>
calling lutimes with tv=0 is valid if the application wants to set the
timestamps to the current time. this commit makes it so the timespec
struct is populated with values from tv only if tv != 0 and calls
utimensat with times=0 if tv == 0.