From: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Date: Wed, 27 Nov 2019 06:33:13 +0000 (+0900)
Subject: hwdep: add global method to get sysname for hwdep device of sound card
X-Git-Tag: v0.1.0~202
X-Git-Url: https://git.alsa-project.org/?a=commitdiff_plain;h=1a97e76098a38963f529dc403a63335af2a83698;p=alsa-gobject.git

hwdep: add global method to get sysname for hwdep device of sound card

Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
---

diff --git a/src/hwdep/alsahwdep.map b/src/hwdep/alsahwdep.map
index 779c754..466d65a 100644
--- a/src/hwdep/alsahwdep.map
+++ b/src/hwdep/alsahwdep.map
@@ -3,6 +3,7 @@ ALSA_GOBJECT_0_0_0 {
     "alsahwdep_iface_type_get_type";
 
     "alsahwdep_get_device_id_list";
+    "alsahwdep_get_hwdep_sysname";
   local:
     *;
 };
diff --git a/src/hwdep/query.c b/src/hwdep/query.c
index 93357e4..1b0a836 100644
--- a/src/hwdep/query.c
+++ b/src/hwdep/query.c
@@ -17,6 +17,7 @@ G_DEFINE_QUARK("alsahwdep-error", alsahwdep_error)
 
 // 'C' is required apart from emulation of Open Sound System.
 #define PREFIX_SYSNAME_TEMPLATE     "hwC%u"
+#define HWDEP_SYSNAME_TEMPLATE      "hwC%uD%u"
 
 static void prepare_udev_enum(struct udev_enumerate **enumerator, GError **error)
 {
@@ -199,3 +200,48 @@ end:
     g_free(prefix);
     release_udev_enum(enumerator);
 }
+
+/**
+ * alsahwdep_get_hwdep_sysname:
+ * @card_id: The numeridcal ID of sound card.
+ * @device_id: The numerical ID of hwdep device for the sound card.
+ * @sysname: (out): The string for sysname of hwdep device.
+ * @error: A #GError.
+ *
+ * Allocate sysname for hwdep device and return it when it exists.
+ */
+void alsahwdep_get_hwdep_sysname(guint card_id, guint device_id,
+                                 char **sysname, GError **error)
+{
+    unsigned int length;
+    char *name;
+    struct udev *ctx;
+    struct udev_device *dev;
+
+    length = strlen(HWDEP_SYSNAME_TEMPLATE) + calculate_digits(card_id) +
+             calculate_digits(device_id) + 1;
+    name = g_try_malloc0(length);
+    if (name == NULL) {
+        generate_error(error, ENOMEM);
+        return;
+    }
+    snprintf(name, length, HWDEP_SYSNAME_TEMPLATE, card_id, device_id);
+
+    ctx = udev_new();
+    if (ctx == NULL) {
+        generate_error(error, errno);
+        g_free(name);
+        return;
+    }
+
+    dev = udev_device_new_from_subsystem_sysname(ctx, "sound", name);
+    if (dev == NULL) {
+        generate_error(error, ENODEV);
+        g_free(name);
+    } else {
+        *sysname = name;
+        udev_device_unref(dev);
+    }
+
+    udev_unref(ctx);
+}
diff --git a/src/hwdep/query.h b/src/hwdep/query.h
index 4cee162..4eed987 100644
--- a/src/hwdep/query.h
+++ b/src/hwdep/query.h
@@ -10,6 +10,9 @@ G_BEGIN_DECLS
 void alsahwdep_get_device_id_list(guint card_id, guint **entries,
                                   gsize *entry_count, GError **error);
 
+void alsahwdep_get_hwdep_sysname(guint card_id, guint device_id,
+                                 char **sysname, GError **error);
+
 G_END_DECLS
 
 #endif