This patch makes a couple of small cleanups to parameter checking of
libfdt functions.
- In several functions which take a node offset, we use an
idiom involving fdt_next_tag() first to check that we have indeed been
given a node offset. This patch adds a helper function
_fdt_check_node_offset() to encapsulate this usage of fdt_next_tag().
- In fdt_rw.c in several places we have the expanded version
of the RW_CHECK_HEADER() macro for no particular reason. This patch
replaces those instances with an invocation of the macro; that's what
it's for.
- In fdt_sw.c we rename the check_header_sw() function to
sw_check_header() to match the analgous function in fdt_rw.c, and we
provide an SW_CHECK_HEADER() wrapper macro as RW_CHECK_HEADER()
functions in fdt_rw.c
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
The fdt_set_header() macro casts an arbitrary pointer into (struct
fdt_header *) to set fdt header fields. While we need to change the
type, so that we can use this macro on the usual (void *) used to
represent a device tree blob, the current macro also casts away any
const on the input pointer, which loses an important check.
This patch replaces the fdt_set_header() macro with a set of inline
functions, one for each header field which do a similar thing, but
which won't silently remove const from a given pointer. This approach
is also more in keeping with the individual accessor macros we use for
reading fdt header fields.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Although it's a low-level function that shouldn't normally be needed,
there are circumstances where it's useful for users of libfdt to use
the _fdt_next_tag() function. Therefore, this patch renames it to
fdt_next_tag() and publishes it in libfdt.h.
In addition, this patch adds a new testcase using fdt_next_tag(),
dtbs_equal_ordered. This testcase tests for structural equality of
two dtbs, including the order of properties and subnodes, but ignoring
NOP tags, the order of the dtb sections and the layout of strings in
the strings block. This will be useful for testing other dtc
functionality in the future.
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
David Gibson