Add a namelen variant of fdt_path_offset to retrieve the node offset using only a fixed number of characters.
Reviewed-by: Simon Glass sjg@chromium.org Signed-off-by: Maxime Ripard maxime.ripard@free-electrons.com --- include/libfdt.h | 16 +++++++++++++++- lib/libfdt/fdt_ro.c | 18 ++++++++++-------- 2 files changed, 25 insertions(+), 9 deletions(-)
diff --git a/include/libfdt.h b/include/libfdt.h index 4643be5adf39..f13b01f08f71 100644 --- a/include/libfdt.h +++ b/include/libfdt.h @@ -365,6 +365,17 @@ int fdt_subnode_offset_namelen(const void *fdt, int parentoffset, */ int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name);
+/** + * fdt_path_offset_namelen - find a tree node based on substring + * @fdt: pointer to the device tree blob + * @path: full path of the node to locate + * @namelen: number of characters of name to consider + * + * Identical to fdt_path_offset(), but only examine the first + * namelen characters of path for matching the node path. + */ +int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen); + /** * fdt_path_offset - find a tree node by its full path * @fdt: pointer to the device tree blob @@ -387,7 +398,10 @@ int fdt_subnode_offset(const void *fdt, int parentoffset, const char *name); * -FDT_ERR_BADSTRUCTURE, * -FDT_ERR_TRUNCATED, standard meanings. */ -int fdt_path_offset(const void *fdt, const char *path); +static inline int fdt_path_offset(const void *fdt, const char *path) +{ + return fdt_path_offset_namelen(fdt, path, strlen(path)); +}
/** * fdt_get_name - retrieve the name of a given node diff --git a/lib/libfdt/fdt_ro.c b/lib/libfdt/fdt_ro.c index 6b737b211d2e..9cc98db6e2bf 100644 --- a/lib/libfdt/fdt_ro.c +++ b/lib/libfdt/fdt_ro.c @@ -145,10 +145,10 @@ int fdt_subnode_offset(const void *fdt, int parentoffset, * "foo/bar:option" and "bar:option/otheroption", both of which happen, so * first searching for either ':' or '/' does not work. */ -static const char *fdt_path_next_separator(const char *path) +static const char *fdt_path_next_separator(const char *path, int len) { - const char *sep1 = strchr(path, '/'); - const char *sep2 = strchr(path, ':'); + const void *sep1 = memchr(path, '/', len); + const void *sep2 = memchr(path, ':', len);
if (sep1 && sep2) return (sep1 < sep2) ? sep1 : sep2; @@ -158,9 +158,9 @@ static const char *fdt_path_next_separator(const char *path) return sep2; }
-int fdt_path_offset(const void *fdt, const char *path) +int fdt_path_offset_namelen(const void *fdt, const char *path, int namelen) { - const char *end = path + strlen(path); + const char *end = path + namelen; const char *p = path; int offset = 0;
@@ -168,7 +168,7 @@ int fdt_path_offset(const void *fdt, const char *path)
/* see if we have an alias */ if (*path != '/') { - const char *q = fdt_path_next_separator(path); + const char *q = fdt_path_next_separator(path, namelen);
if (!q) q = end; @@ -181,14 +181,16 @@ int fdt_path_offset(const void *fdt, const char *path) p = q; }
- while (*p) { + while (*p && (p < end)) { const char *q;
while (*p == '/') p++; + if (*p == '\0' || *p == ':') return offset; - q = fdt_path_next_separator(p); + + q = fdt_path_next_separator(p, end - p); if (!q) q = end;