[vlc-devel] commit: udev: refactor (binary search tree) ( Rémi Denis-Courmont )
git version control
git at videolan.org
Sat Oct 17 16:57:33 CEST 2009
vlc | branch: master | Rémi Denis-Courmont <remi at remlab.net> | Sat Oct 17 17:49:56 2009 +0300| [0d904f9784b6783185d971cdd6d7b33157d9231e] | committer: Rémi Denis-Courmont
udev: refactor (binary search tree)
> http://git.videolan.org/gitweb.cgi/vlc.git/?a=commit;h=0d904f9784b6783185d971cdd6d7b33157d9231e
---
modules/services_discovery/udev.c | 178 +++++++++++++++++++++++-------------
1 files changed, 114 insertions(+), 64 deletions(-)
diff --git a/modules/services_discovery/udev.c b/modules/services_discovery/udev.c
index 9215008..1bde9c9 100644
--- a/modules/services_discovery/udev.c
+++ b/modules/services_discovery/udev.c
@@ -28,6 +28,7 @@
#include <vlc_common.h>
#include <vlc_services_discovery.h>
#include <vlc_plugin.h>
+#include <search.h>
#include <poll.h>
#include <errno.h>
@@ -58,6 +59,12 @@ vlc_module_begin ()
vlc_module_end ()
+struct device
+{
+ dev_t devnum; /* must be first */
+ input_item_t *item;
+};
+
struct subsys
{
const char *name;
@@ -71,12 +78,108 @@ struct services_discovery_sys_t
const struct subsys *subsys;
struct udev_monitor *monitor;
vlc_thread_t thread;
- input_item_t **itemv;
- size_t itemc;
+ void *root;
};
+/**
+ * Compares two devices (to support binary search).
+ */
+static int cmpdev (const void *a, const void *b)
+{
+ const dev_t *da = a, *db = b;
+ dev_t delta = *da - *db;
+
+ if (sizeof (delta) > sizeof (int))
+ return delta ? ((delta > 0) ? 1 : -1) : 0;
+ return (signed)delta;
+}
+
+static void DestroyDevice (void *data)
+{
+ struct device *d = data;
+
+ vlc_gc_decref (d->item);
+ free (d);
+}
+
+static char *decode_property (struct udev_device *, const char *);
+
+/**
+ * Adds a udev device.
+ */
+static int AddDevice (services_discovery_t *sd, struct udev_device *dev)
+{
+ services_discovery_sys_t *p_sys = sd->p_sys;
+
+ char *mrl = p_sys->subsys->get_mrl (dev);
+ if (mrl == NULL)
+ return 0; /* don't know if it was an error... */
+ char *name = p_sys->subsys->get_name (dev);
+ input_item_t *item = input_item_NewWithType (VLC_OBJECT (sd), mrl,
+ name ? name : mrl,
+ 0, NULL, 0, -1, ITEM_TYPE_CARD);
+ msg_Dbg (sd, "adding %s (%s)", mrl, name);
+ free (name);
+ free (mrl);
+ if (item == NULL)
+ return -1;
+
+ struct device *d = malloc (sizeof (*d));
+ if (d == NULL)
+ {
+ vlc_gc_decref (item);
+ return -1;
+ }
+ d->item = item;
+ d->devnum = udev_device_get_devnum (dev);
+
+ struct device **dp = tsearch (d, &p_sys->root, cmpdev);
+ if (dp == NULL) /* Out-of-memory */
+ {
+ DestroyDevice (d);
+ return -1;
+ }
+ if (*dp != d) /* Overwrite existing device */
+ {
+ services_discovery_RemoveItem (sd, (*dp)->item);
+ DestroyDevice (*dp);
+ *dp = d;
+ }
+
+ name = p_sys->subsys->get_cat (dev);
+ services_discovery_AddItem (sd, item, name ? name : "Generic");
+ free (name);
+ return 0;
+}
+
+/**
+ * Removes a udev device (if present).
+ */
+static void RemoveDevice (services_discovery_t *sd, struct udev_device *dev)
+{
+ services_discovery_sys_t *p_sys = sd->p_sys;
+
+ dev_t num = udev_device_get_devnum (dev);
+ struct device **dp = tfind (&(dev_t){ num }, &p_sys->root, cmpdev);
+ if (dp == NULL)
+ return;
+
+ struct device *d = *dp;
+ services_discovery_RemoveItem (sd, d->item);
+ tdelete (d, &p_sys->root, cmpdev);
+ DestroyDevice (d);
+}
+
+static void HandleDevice (services_discovery_t *sd, struct udev_device *dev,
+ bool add)
+{
+ if (!add)
+ RemoveDevice (sd, dev);
+ else
+ AddDevice (sd, dev);
+}
+
static void *Run (void *);
-static void HandleDevice (services_discovery_t *, struct udev_device *, bool);
/**
* Probes and initializes.
@@ -90,8 +193,7 @@ static int Open (vlc_object_t *obj, const struct subsys *subsys)
return VLC_ENOMEM;
sd->p_sys = p_sys;
p_sys->subsys = subsys;
- p_sys->itemv = NULL;
- p_sys->itemc = 0;
+ p_sys->root = NULL;
struct udev_monitor *mon = NULL;
struct udev *udev = udev_new ();
@@ -148,7 +250,6 @@ error:
return VLC_EGENERIC;
}
-
/**
* Releases resources
*/
@@ -167,13 +268,10 @@ static void Close (vlc_object_t *obj)
udev_unref (udev);
}
- for (size_t i = 0; i < p_sys->itemc; i++)
- vlc_gc_decref (p_sys->itemv[i]);
- free (p_sys->itemv);
+ tdestroy (p_sys->root, DestroyDevice);
free (p_sys);
}
-
static void *Run (void *data)
{
services_discovery_t *sd = data;
@@ -205,6 +303,9 @@ static void *Run (void *data)
return NULL;
}
+/**
+ * Converts an hexadecimal digit to an integer.
+ */
static int hex (char c)
{
if (c >= '0' && c <= '9')
@@ -216,6 +317,9 @@ static int hex (char c)
return -1;
}
+/**
+ * Decodes a udev hexadecimal-encoded property.
+ */
static char *decode (const char *enc)
{
char *ret = enc ? strdup (enc) : NULL;
@@ -249,60 +353,6 @@ static char *decode_property (struct udev_device *dev, const char *name)
return decode (udev_device_get_property_value (dev, name));
}
-static void HandleDevice (services_discovery_t *sd, struct udev_device *dev,
- bool add)
-{
- services_discovery_sys_t *p_sys = sd->p_sys;
-
- /* Determine media location */
- char *mrl = p_sys->subsys->get_mrl (dev);
- if (mrl == NULL)
- return;
-
- /* Find item in list */
- input_item_t *item = NULL;
- size_t i;
-
- for (i = 0; i < p_sys->itemc; i++)
- {
- input_item_t *oitem = p_sys->itemv[i];
- char *omrl = input_item_GetURI (oitem);
-
- if (!strcmp (omrl, mrl))
- {
- item = oitem;
- break;
- }
- }
-
- /* Add/Remove old item */
- if (add && (item == NULL))
- {
- char *name = p_sys->subsys->get_name (dev);
- item = input_item_NewWithType (VLC_OBJECT (sd), mrl,
- name ? name : "Unnamed",
- 0, NULL, 0, -1, ITEM_TYPE_CARD);
- free (name);
- if (item != NULL)
- {
- msg_Dbg (sd, "adding %s", mrl);
- name = p_sys->subsys->get_cat (dev);
- services_discovery_AddItem (sd, item, name ? name : "Generic");
- free (name);
-
- TAB_APPEND (p_sys->itemc, p_sys->itemv, item);
- }
- }
- else if (!add && (item != NULL))
- {
- msg_Dbg (sd, "removing %s", mrl);
- services_discovery_RemoveItem (sd, item);
- vlc_gc_decref (item);
- TAB_REMOVE (p_sys->itemc, p_sys->itemv, i);
- }
- free (mrl);
-}
-
/*** Video4Linux support ***/
static bool is_v4l_legacy (struct udev_device *dev)
{
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