On 2023-01-18 11:14:50 Wed, Athira Rajeev wrote:
> Add a function dt_find_by_name_substr() that returns the child node if
> it matches till first occurence at "@" of a given name, otherwise NULL.
> This is helpful for cases with node name like: "name@addr". In
> scenarios where nodes are added with "name@addr" format and if the
> value of "addr" is not known, that node can't be matched with node
> name or addr. Hence matching with substring as node name will return
> the expected result. Patch adds dt_find_by_name_substr() function
> and testcase for the same in core/test/run-device.c
>
> Signed-off-by: Athira Rajeev <atraj...@linux.vnet.ibm.com>
> ---
> Changelog:
> v1 -> v2:
> - Addressed review comment from Dan to update
> the utility funtion to search and compare
> upto "@". Renamed it as dt_find_by_name_substr.
>
> core/device.c | 18 ++++++++++++++++++
> core/test/run-device.c | 11 +++++++++++
> include/device.h | 3 +++
> 3 files changed, 32 insertions(+)
>
> diff --git a/core/device.c b/core/device.c
> index 2de37c74..df3a5775 100644
> --- a/core/device.c
> +++ b/core/device.c
> @@ -395,6 +395,24 @@ struct dt_node *dt_find_by_name(struct dt_node *root,
> const char *name)
> }
>
>
> +struct dt_node *dt_find_by_name_substr(struct dt_node *root, const char
> *name)
> +{
> + struct dt_node *child, *match;
> + char *pos;
> +
> + list_for_each(&root->children, child, list) {
> + pos = strchr(child->name, '@');
> + if (!strncmp(child->name, name, pos - child->name))
Shouldn't we care about string length of substring to be checked before
comparision ? The code assumes that it is always within the limit of
position of '@' in node name string. Hence, it returns a wrong node
whose name partially matches with substring passed.
e.g.
With following two nodes in deviec tree (as per your test):
/node@1
/node0_1@2
the substring 'node0', 'node0@' and 'node0_@' all matches with 'node@1' device
tree node.
Is this expected ?
Also, what do you expect dt_find_by_name_substr() to return for string
like 'node0' and 'node0_' ? NULL or node '/node0_1@2' ?
> + return child;
> +
> + match = dt_find_by_name_substr(child, name);
> + if (match)
> + return match;
> + }
> +
> + return NULL;
> +}
> +
> struct dt_node *dt_new_check(struct dt_node *parent, const char *name)
> {
> struct dt_node *node = dt_find_by_name(parent, name);
> diff --git a/core/test/run-device.c b/core/test/run-device.c
> index 4a12382b..0e463e58 100644
> --- a/core/test/run-device.c
> +++ b/core/test/run-device.c
> @@ -466,6 +466,17 @@ int main(void)
> new_prop_ph = dt_prop_get_u32(ut2, "something");
> assert(!(new_prop_ph == ev1_ph));
> dt_free(subtree);
> +
> + /* Test dt_find_by_name_substr */
> + root = dt_new_root("");
> + addr1 = dt_new_addr(root, "node", 0x1);
> + addr2 = dt_new_addr(root, "node0_1", 0x2);
> + assert(dt_find_by_name(root, "node@1") == addr1);
> + assert(dt_find_by_name(root, "node0_1@2") == addr2);
> + assert(dt_find_by_name_substr(root, "node@1") == addr1);
> + assert(dt_find_by_name_substr(root, "node0_1@2") == addr2);
Below additional tests are failing:
assert(dt_find_by_name_substr(root, "node0@") == NULL);
assert(dt_find_by_name_substr(root, "node0_@") == NULL);
Maybe we should add few more test checks for "node0" and "node0_" as well.
Thanks,
-Mahesh.
