This macro will read a pointer of any type, return it, and set the
pointer to NULL. This is useful as an explicit concept of passing
ownership of a memory area between pointers.
This takes inspiration from Rust:
https://doc.rust-lang.org/std/option/enum.Option.html#method.take
and was suggested by Alan Jenkins (@sourcejedi).
It drops ~160 lines of code from our codebase, which makes me like it.
Also, I think it clarifies passing of ownership, and thus helps
readability a bit (at least for the initiated who know the new macro)
This patch adds safe_atoux16 for parsing an unsigned hexadecimal 16bit int, and
uses that for parsing USB device and vendor IDs.
This fixes a compile error with gcc-8 because while we know that USB IDs are 2 bytes,
the compiler does not know that.
../src/udev/udev-builtin-hwdb.c:80:38: error: '%04X' directive output may be
truncated writing between 4 and 8 bytes into a region of size between 2 and 6
[-Werror=format-truncation=]
Signed-off-by: Adam Williamson <awilliam@redhat.com>
Signed-off-by: Patrick Uiterwijk <puiterwijk@redhat.com>
Checking for validity of a PID is relatively easy, but let's add a
helper cal for this too, in order to make things more readable and more
similar to uid_is_valid(), gid_is_valid() and friends.
This adds parse_nice() that parses a nice level and ensures it is in the right
range, via a new nice_is_valid() helper. It then ports over a number of users
to this.
No functional changes.
strtoull() doesn't make it particularly easy to detect passed-in
negative numbers, as it silently converts them to positive ones without
generating any error. Since we are not interested in negative values we
should hence explicitly filter them out by looking at the string
directly and returning ERANGE if we see a leading "-".
Fixes: #1829
Lennart Poettering