diff options
author | Simon Glass <sjg@chromium.org> | 2013-05-07 06:11:50 (GMT) |
---|---|---|
committer | Tom Rini <trini@ti.com> | 2013-05-14 19:37:25 (GMT) |
commit | 88f95bbadda89bfaf6a8e817bb66fd114afc1caf (patch) | |
tree | 17a3c26a6ef0df9a2469c55848a3949bebd3b3d8 /lib/libfdt/fdt.c | |
parent | 816cb037adf94ead77593812ccd3244d506175fa (diff) | |
download | u-boot-88f95bbadda89bfaf6a8e817bb66fd114afc1caf.tar.xz |
libfdt: Add fdt_next_subnode() to permit easy subnode iteration
Iterating through subnodes with libfdt is a little painful to write as we
need something like this:
for (depth = 0, count = 0,
offset = fdt_next_node(fdt, parent_offset, &depth);
(offset >= 0) && (depth > 0);
offset = fdt_next_node(fdt, offset, &depth)) {
if (depth == 1) {
/* code body */
}
}
Using fdt_next_subnode() we can instead write this, which is shorter and
easier to get right:
for (offset = fdt_first_subnode(fdt, parent_offset);
offset >= 0;
offset = fdt_next_subnode(fdt, offset)) {
/* code body */
}
Also, it doesn't require two levels of indentation for the loop body.
Signed-off-by: Simon Glass <sjg@chromium.org>
(Cherry-picked from dtc commit 4e76ec79)
Acked-by: Gerald Van Baren <vanbaren@cideas.com>
Diffstat (limited to 'lib/libfdt/fdt.c')
-rw-r--r-- | lib/libfdt/fdt.c | 28 |
1 files changed, 28 insertions, 0 deletions
diff --git a/lib/libfdt/fdt.c b/lib/libfdt/fdt.c index 387e354..154e9a4 100644 --- a/lib/libfdt/fdt.c +++ b/lib/libfdt/fdt.c @@ -202,6 +202,34 @@ int fdt_next_node(const void *fdt, int offset, int *depth) return offset; } +int fdt_first_subnode(const void *fdt, int offset) +{ + int depth = 0; + + offset = fdt_next_node(fdt, offset, &depth); + if (offset < 0 || depth != 1) + return -FDT_ERR_NOTFOUND; + + return offset; +} + +int fdt_next_subnode(const void *fdt, int offset) +{ + int depth = 1; + + /* + * With respect to the parent, the depth of the next subnode will be + * the same as the last. + */ + do { + offset = fdt_next_node(fdt, offset, &depth); + if (offset < 0 || depth < 1) + return -FDT_ERR_NOTFOUND; + } while (depth > 1); + + return offset; +} + const char *_fdt_find_string(const char *strtab, int tabsize, const char *s) { int len = strlen(s) + 1; |