ao_coreaudio: reset possibly random errno value

In general, you need to check errno when using strtol(), but as far as I
know, strtol() won't reset errno on success. This has to be done
manually. The code could have failed sporadically if strtol() succeeded,
and errno was already set to one of the checked values.

(This strtol() still isn't fully error checked, but I don't know if it's
intentional, e.g. for parsing a numeric prefix only.)

1 files changed, 2 insertions, 1 deletions

diff --git a/audio/out/ao_coreaudio_utils.c b/audio/out/ao_coreaudio_utils.c
index 8d85842dfd..fe8354939a 100644
--- a/audio/out/ao_coreaudio_utils.c
+++ b/audio/out/ao_coreaudio_utils.c
@@ -65,7 +65,8 @@ coreaudio_error:
 OSStatus ca_select_device(struct ao *ao, char* name, AudioDeviceID *device)
 {
     OSStatus err = noErr;
-    int selection = name ? strtol(name, (char **)NULL, 10) : -1;
+    errno = 0;
+    int selection = name && name[0] ? strtol(name, (char **)NULL, 10) : -1;
     if (errno == EINVAL || errno == ERANGE) {
         selection = -1;
         MP_WARN(ao, "device identifier '%s' is invalid\n", name);