Kumar has already added alias expansion to fdt_path_offset().
However, in some circumstances it may be convenient for the user of
libfdt to explicitly get the string expansion of an alias.  This patch
adds a function to do this, fdt_get_alias(), and uses it to implement
fdt_path_offset().

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

Using Gcc 4.3 detected this problem:

    ../dtc/libfdt/fdt.c: In function 'fdt_next_tag':
    ../dtc/libfdt/fdt.c:82: error: assuming signed overflow does not
    occur when assuming that (X + c) < X is always false

To fix the problem, treat the offset as an unsigned int.

The problem report and proposed fix were provided
by Steve Papacharalambous <stevep@freescale.com>.

Signed-off-by: Jon Loeliger <jdl@freescale.com>

The current implementation of fdt_get_path() has a couple of bugs,
fixed by this patch.

First, contrary to its documentation, on success it returns the length
of the node's path, rather than 0.  The testcase is correspondingly
wrong, and the patch fixes this as well.

Second, in some circumstances, it will return -FDT_ERR_BADOFFSET
instead of -FDT_ERR_NOSPACE when given insufficient buffer space.
Specifically this happens when there is insufficient space even to
hold the path's second last component.  This behaviour is corrected,
and the testcase updated to check it.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

If the path doesn't start with '/' check to see if it matches some alias
under "/aliases" and substitute the matching alias value in the path
and retry the lookup.

Signed-off-by: Kumar Gala <galak@kernel.crashing.org>
Acked-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Gerald Van Baren <vanbaren@cideas.com>

As well as fdt_subnode_offset(), libfdt includes an
fdt_subnode_offset_namelen() function that takes the subnode name to
look up not as a NUL-terminated string, but as a string with an
explicit length.  This can be useful when the caller has the name as
part of a longer string, such as a full path.

However, we don't have corresponding 'namelen' versions for
fdt_get_property() and fdt_getprop().  There are less obvious use
cases for these variants on property names, but there are
circumstances where they can be useful e.g. looking up property names
which need to be parsed from a longer string buffer such as user input
or a configuration file, or looking up an alias in a path with
IEEE1275 style aliases.

So, since it's very easy to implement such variants, this patch does
so.  The original NUL-terminated variants are, of course, implemented
in terms of the namelen versions.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

In commit b6d80a20fc293f3b995c3ce1a6744a5574192125, we renamed all
libfdt functions to be prefixed with fdt_ or _fdt_ to minimise the
chance of collisions with things from whatever package libfdt is
embedded in, pulled into the libfdt build via that environment's
libfdt_env.h.

Except... I missed one.  This patch applies the same treatment to
_stringlist_contains().  While we're at it, also make it static since
it's only used in the same file.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

libfdt is supposed to easy to embed in projects all and sundry.
Often, it won't be practical to separate the embedded libfdt's
namespace from that of the surrounding project.  Which means there can
be namespace conflicts between even libfdt's internal/static functions
and functions or macros coming from the surrounding project's headers
via libfdt_env.h.

This patch, therefore, renames a bunch of libfdt internal functions
and macros and makes a few other chances to reduce the chances of
namespace collisions with embedding projects.  Specifically:
	- Internal functions (even static ones) are now named _fdt_*()

	- The type and (static) global for the error table in
          fdt_strerror() gain an fdt_ prefix

	- The unused macro PALIGN is removed

	- The memeq and streq macros are removed and open-coded in the
          users (they were only used once each)

	- Other macros gain an FDT_ prefix

	- To save some of the bulk from the previous change, an
          FDT_TAGALIGN() macro is introduced, where FDT_TAGALIGN(x) ==
          FDT_ALIGN(x, FDT_TAGSIZE)

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>

Enabling -Wcast-qual warnings in dtc shows up a number of places where
we are incorrectly discarding a const qualification.  There are also
some places where we are intentionally discarding the 'const', and we
need an ugly cast through uintptr_t to suppress the warning.  However,
most of these are pretty well isolated with the *_w() functions.  So
in the interests of maximum safety with const qualifications, this
patch enables the warnings and fixes the existing complaints.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Acked-by: Gerald Van Baren <vanbaren@cideas.com>

This patch turns on the -Wpointer-arith option in the dtc Makefile,
and fixes the resulting warnings due to using (void *) in pointer
arithmetic.  While convenient, pointer arithmetic on void * is not
portable, so it's better that we avoid it, particularly in libfdt.

Also add necessary definition of uintptr_t needed by David Gibson's
changeset "dtc: Enable and fix -Wpointer-arith warnings" (the definition
comes from stdint.h, which u-boot doesn't have). -- gvb

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Gerald Van Baren <vanbaren@cideas.com>

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>