The dns_message_create() function cannot soft fail (as all memory
allocations either succeed or cause abort), so we change the function to
return void and cleanup the calls.
(cherry picked from commit 33eefe9f85)
dns_message_t objects are now being handled using reference counting
semantics, so now dns_message_destroy() is not called directly anymore,
dns_message_detach must be called instead.
(cherry picked from commit 7deaf9a93c)
Also disable the semantic patch as the code needs tweaks here and there because
some destroy functions might not destroy the object and return early if the
object is still in use.
Our destroy functions usually look like this:
void
foo_destroy(foo_t **foop) {
foo_t foo = *foop;
...destroy the contents of foo...
*foop = NULL;
}
nulling the pointer should be done as soon as possible which is
not always the case. This commit adds simple semantic patch that
changes the example function to:
void
foo_destroy(foo_t **foop) {
foo_t foo = *foop;
*foop = NULL;
...destroy the contents of foo...
}
When a function returns void, it can be used as an argument to return in
function returning also void, e.g.:
void in(void) {
return;
}
void out(void) {
return (in());
}
while this is legal, it should be rewritten as:
void out(void) {
in();
return;
}
The semantic patch just find the occurrences, and they need to be fixed
by hand.
Some semantic patches are meant to be run just once, as they work on
functions with changed prototypes. We keep them for reference, but
disabled them from the CI to save time.
The dns_name_copy() function cannot fail gracefully when the last argument
(target) is NULL. Add RUNTIME_CHECK()s around such calls.
The first semantic patch adds RUNTIME_CHECK() around any call that ignores the
return value and is very safe to apply.
The second semantic patch attempts to properly add RUNTIME_CHECK() to places
where the return value from `dns_name_copy()` is recorded into `result`
variable. The result of this semantic patch needs to be reviewed by hand.
Both patches misses couple places where the code surrounding the
`dns_name_copy(..., NULL)` usage is more complicated and is better suited to be
fixed by a human being that understands the surrounding code.
The isc_mem_get() cannot fail gracefully now, it either gets memory of
assert()s. The added semantic patch cleans all the blocks checking whether
the return value of isc_mem_get() was NULL.
