[v2] ucm: add existence checks to geti calls

Commit Message

Curtis Malainey Jan. 13, 2023, 6:50 p.m. UTC

From: Curtis Malainey <[e-mail]>

Right now in snd_use_case_geti you cannot tell if the item being queried
exists or not when being checked. This also means the only way to check
for the existence of something in the client of the library is to
iterate over the list of mods/devs even if we know exactly the name we
are looking for. We have functions that do exactly this internally so
lets return this information in a logical fashion through geti.

Signed-off-by: Curtis Malainey <[e-mail]>
---
 src/ucm/main.c | 6 ++++++
 1 file changed, 6 insertions(+)

Comments

Jaroslav Kysela Jan. 13, 2023, 7:32 p.m. UTC | #1

On 13. 01. 23 19:50, [e-mail] wrote:
> From: Curtis Malainey <[e-mail]>
> 
> Right now in snd_use_case_geti you cannot tell if the item being queried
> exists or not when being checked. This also means the only way to check
> for the existence of something in the client of the library is to
> iterate over the list of mods/devs even if we know exactly the name we
> are looking for. We have functions that do exactly this internally so
> lets return this information in a logical fashion through geti.

The device_status/modifier_status functions are used internally, too.
I would add the device validation only to the geti code. The other parts do 
this job already and expect just 0 or 1 return values.

				Jaroslav

Curtis Malainey Jan. 13, 2023, 7:36 p.m. UTC | #2

On Fri, Jan 13, 2023 at 11:32 AM Jaroslav Kysela <[e-mail]> wrote:
>
> On 13. 01. 23 19:50, [e-mail] wrote:
> > From: Curtis Malainey <[e-mail]>
> >
> > Right now in snd_use_case_geti you cannot tell if the item being queried
> > exists or not when being checked. This also means the only way to check
> > for the existence of something in the client of the library is to
> > iterate over the list of mods/devs even if we know exactly the name we
> > are looking for. We have functions that do exactly this internally so
> > lets return this information in a logical fashion through geti.
>
> The device_status/modifier_status functions are used internally, too.
> I would add the device validation only to the geti code. The other parts do
> this job already and expect just 0 or 1 return values.
>
>                                 Jaroslav

Understood, I will move it back to geti directly, figured this was the
cleanest place to put it but that makes sense if other places use
those internal functions.

>
> --
> Jaroslav Kysela <[e-mail]>
> Linux Sound Maintainer; ALSA Project; Red Hat, Inc.

Patch

diff --git a/src/ucm/main.c b/src/ucm/main.c
index 2ff4d3f3..adbddc26 100644
--- a/src/ucm/main.c
+++ b/src/ucm/main.c
@@ -1321,6 +1321,9 @@  long device_status(snd_use_case_mgr_t *uc_mgr,
 		if (strcmp(dev->name, device_name) == 0)
 			return 1;
 	}
+	dev = find_device(uc_mgr, uc_mgr->active_verb, device_name, 0);
+	if (!dev)
+		return -ENOENT;
 	return 0;
 }
 
@@ -1335,6 +1338,9 @@  long modifier_status(snd_use_case_mgr_t *uc_mgr,
 		if (strcmp(mod->name, modifier_name) == 0)
 			return 1;
 	}
+	mod = find_modifier(uc_mgr, uc_mgr->active_verb, modifier_name, 0);
+	if (!mod)
+		return -ENOENT;
 	return 0;
 }