On 18 January 2016 at 15:16, Eric Auger <eric.au...@linaro.org> wrote:
> This new helper routine returns a NULL terminated array of
> node paths matching a node name and a compat string.
>
> Signed-off-by: Eric Auger <eric.au...@linaro.org>
>
> ---
>
> v4 -> v5:
> - support the case where several nodes exist, ie.
> return an array of node paths. Also add Error **
> parameter
>
> v1 -> v2:
> - move doc comment in header file
> - do not use a fixed size buffer
> - break on errors in while loop
> - use strcmp instead of strncmp
>
> RFC -> v1:
> - improve error handling according to Alex' comments
> ---
> device_tree.c | 49
> ++++++++++++++++++++++++++++++++++++++++++++
> include/sysemu/device_tree.h | 14 +++++++++++++
> 2 files changed, 63 insertions(+)
>
> diff --git a/device_tree.c b/device_tree.c
> index b262c2d..3c88a37 100644
> --- a/device_tree.c
> +++ b/device_tree.c
> @@ -231,6 +231,55 @@ static int findnode_nofail(void *fdt, const char
> *node_path)
> return offset;
> }
>
> +char **qemu_fdt_node_path(void *fdt, const char *name, char *compat,
> + Error **errp)
> +{
> + int offset, len, ret;
> + const char *iter_name;
> + unsigned int path_len = 16, n = 0;
> + GSList *path_list = NULL, *iter;
> + char **path_array;
> +
> + offset = fdt_node_offset_by_compatible(fdt, -1, compat);
> +
> + while (offset >= 0) {
> + iter_name = fdt_get_name(fdt, offset, &len);
> + if (!iter_name) {
> + offset = len;
> + break;
> + }
> + if (!strcmp(iter_name, name)) {
> + char *path;
> +
> + path = g_malloc(path_len);
> + while ((ret = fdt_get_path(fdt, offset, path, path_len))
> + == -FDT_ERR_NOSPACE) {
> + path_len += 16;
> + path = g_realloc(path, path_len);
> + }
> + path_list = g_slist_prepend(path_list, path);
> + n++;
> + }
> + offset = fdt_node_offset_by_compatible(fdt, offset, compat);
> + }
> +
> + if (offset < 0 && offset != -FDT_ERR_NOTFOUND) {
> + error_setg(errp, "%s: abort parsing dt for %s/%s: %s",
> + __func__, name, compat, fdt_strerror(offset));
Needs to bail out (freeing memory).
> + }
> +
> + path_array = g_new(char *, n + 1);
> + path_array[n--] = NULL;
0, or '\0'. NULL is a pointer, not the NUL character. (This is a
style issue, not a correctness one.)
> +
> + for (iter = path_list; iter; iter = iter->next) {
> + path_array[n--] = iter->data;
> + }
> +
> + g_slist_free(path_list);
> +
> + return path_array;
> +}
> +
> int qemu_fdt_setprop(void *fdt, const char *node_path,
> const char *property, const void *val, int size)
> {
> diff --git a/include/sysemu/device_tree.h b/include/sysemu/device_tree.h
> index fdf25a4..436b5dd 100644
> --- a/include/sysemu/device_tree.h
> +++ b/include/sysemu/device_tree.h
> @@ -20,6 +20,20 @@ void *load_device_tree(const char *filename_path, int
> *sizep);
> void *load_device_tree_from_sysfs(void);
> #endif
>
> +/**
> + * qemu_fdt_node_path: return the paths of nodes matching a given
> + * name and compat string
> + * @fdt: pointer to the dt blob
> + * @name: node name
> + * @compat: compatibility string
> + * @errp: handle to an error object
> + *
> + * returns a newly allocated NULL-terminated array of node paths.
Should say what we return on error (NULL ?)
> + * Use g_strfreev() to free it.
> + */
> +char **qemu_fdt_node_path(void *fdt, const char *name, char *compat,
> + Error **errp);
> +
> int qemu_fdt_setprop(void *fdt, const char *node_path,
> const char *property, const void *val, int size);
> int qemu_fdt_setprop_cell(void *fdt, const char *node_path,
> --
> 1.9.1
>
thanks
-- PMM
