On Fri, Dec 21, 2007 at 11:09:21AM -0600, Scott Wood wrote:

On Fri, Dec 21, 2007 at 11:29:22AM +1100, David Gibson wrote:

quoted

On Thu, Dec 20, 2007 at 01:52:59PM -0600, Scott Wood wrote:

quoted

A property's data can be populated with a file's contents
as follows:

node {
	prop = /bin-include/ "path/to/data";
};

I'd be inclined to use /incbin/ rather than /bin-include/.  It's only
slightly less obvious, but it's then the same as the gas pseudo-op as
well as being a little briefer.

OK.

quoted

quoted

Search paths are not yet implemented; non-absolute lookups are relative to
the directory from which dtc was invoked.

Hrm.  I think that's a bit too bogus.  Although it's rather more work
to implement, I think we have to make relative paths relative to the
location of the dts file until search paths are implemented.

OK.  I was being lazy. :-P

In general I'd approve, but having to invoke dtc in the right place
for the dts file is a bit too big a usability problem, I think.

quoted

quoted

+	| propdataprefix DT_BININCLUDE DT_STRING
+		{
+			struct stat st;
+			FILE *f;
+			int fd;
+			
+			f = fopen($3.val, "rb");
+			if (!f) {
+				yyerrorf("Cannot open file \"%s\": %s",
+				         $3.val, strerror(errno));
+				YYERROR;

Hrm.  I'm not sure that being unable to open the file should cause a
*parse* error which is what YYERROR will do.  Probably better to print
an error message, but let the parsing continue, with the property
value being as though the file were empty.

Yeah, I wanted something that would cause dtc to return an error code,
and it doesn't seem that calling yyerror(f) will do that at present.  I
guess I should fix that rather than overload YYERROR.

No.  As per the yacc interface, yyerror() prints only, it doesn't
terminate.

You could use die(), although that might be an excessively scary
message for the situation.

quoted

quoted

+			}
+
+			fd = fileno(f);
+			if (fstat(fd, &st) < 0) {
+				yyerrorf("Cannot stat file \"%s\": %s",
+				         $3.val, strerror(errno));
+				YYERROR;
+			}

I'm also not sure that stat()ing the file is a good way to get the
size.  This requires that the included file be a regular file with a
sane st_size value, and I can imagine cases where it might be useful
to incbin from a /dev node or other special file.  Obviosuly
implementing that will require work to data_copy_file().

Hmm...  do you have a use case in mind?

Nothing really specific.  I'm thinking of a dts that maybe pulls in
some blobs from a pre-existing firmware, by sucking in files from
/proc/device-tree.  Or maybe something to produce a dts for a guest
under a hypervisor that takes an image of a real NVRAM or other device
to embed in the tree as a virtual NVRAM for the guest.

It's not a big deal, but since it shouldn't be that hard in principle
to read in a whole file without getting an st_size first.

quoted

Actually, I think the way to go here would be to have two variants of
the incbin directive:  one which takes just a filename and includes
the whole file contents, another which takes a filename and a number
and includes just the first N bytes of the file.

Maybe.  /incbinrange/ "path/name" start len?

I'd prefer to avoid two different keywords if possible.  I'll see if I
can think of a reasonable syntax.

quoted

quoted

diff --git a/dtc.h b/dtc.h
index 9b89689..87b5bb1 100644
--- a/dtc.h
+++ b/dtc.h

@@ -138,6 +138,7 @@ struct data data_grow_for(struct data d, int xlen);
 struct data data_copy_mem(const char *mem, int len);
 struct data data_copy_escape_string(const char *s, int len);
 struct data data_copy_file(FILE *f, size_t len);
+struct data data_bin_include(const char *filename);

This looks like a hangover from an earlier version.

Oops, yes.

-Scott
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-- 
David Gibson			| I'll have my music baroque, and my code
david AT gibson.dropbear.id.au	| minimalist, thank you.  NOT _the_ _other_
				| _way_ _around_!
http://www.ozlabs.org/~dgibson