chiark / gitweb /
libudev: enumerate - add udev_enumerate_add_match_parent()
authorKay Sievers <kay.sievers@vrfy.org>
Thu, 7 Jul 2011 22:42:35 +0000 (00:42 +0200)
committerKay Sievers <kay.sievers@vrfy.org>
Thu, 7 Jul 2011 22:42:35 +0000 (00:42 +0200)
libudev/docs/libudev-sections.txt
libudev/libudev-enumerate.c
libudev/libudev.h
udev/udevadm-trigger.c
udev/udevadm.xml

index 6ccd025..4cd383b 100644 (file)
@@ -94,6 +94,7 @@ udev_enumerate_add_match_sysattr
 udev_enumerate_add_nomatch_sysattr
 udev_enumerate_add_match_property
 udev_enumerate_add_match_tag
+udev_enumerate_add_match_parent
 udev_enumerate_add_match_is_initialized
 udev_enumerate_add_match_sysname
 udev_enumerate_add_syspath
index 0b028ba..320ab66 100644 (file)
@@ -52,6 +52,7 @@ struct udev_enumerate {
        struct udev_list_node sysname_match_list;
        struct udev_list_node properties_match_list;
        struct udev_list_node tags_match_list;
+       struct udev_device *parent_match;
        struct udev_list_node devices_list;
        struct syspath *devices;
        unsigned int devices_cur;
@@ -125,6 +126,7 @@ UDEV_EXPORT void udev_enumerate_unref(struct udev_enumerate *udev_enumerate)
        udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->sysname_match_list);
        udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->properties_match_list);
        udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->tags_match_list);
+       udev_device_unref(udev_enumerate->parent_match);
        udev_list_cleanup_entries(udev_enumerate->udev, &udev_enumerate->devices_list);
        for (i = 0; i < udev_enumerate->devices_cur; i++)
                free(udev_enumerate->devices[i].syspath);
@@ -460,6 +462,30 @@ UDEV_EXPORT int udev_enumerate_add_match_tag(struct udev_enumerate *udev_enumera
 }
 
 /**
+ * udev_enumerate_add_match_parent:
+ * @udev_enumerate: context
+ * @parent: filter for the parent device
+ *
+ * Return only the children of a given device.
+ *
+ * A reference for the device is held until the udev_enumerate context
+ * is cleaned up.
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ */
+UDEV_EXPORT int udev_enumerate_add_match_parent(struct udev_enumerate *udev_enumerate, struct udev_device *parent)
+{
+       if (udev_enumerate == NULL)
+               return -EINVAL;
+       if (parent == NULL)
+               return 0;
+       if (udev_enumerate->parent_match != NULL)
+               udev_device_unref(udev_enumerate->parent_match);
+       udev_enumerate->parent_match = udev_device_ref(parent);
+       return 0;
+}
+
+/**
  * udev_enumerate_add_match_is_initialized:
  * @udev_enumerate: context
  *
@@ -581,6 +607,17 @@ static bool match_tag(struct udev_enumerate *udev_enumerate, struct udev_device
        return true;
 }
 
+static bool match_parent(struct udev_enumerate *udev_enumerate, struct udev_device *dev)
+{
+       const char *parent;
+
+       if (udev_enumerate->parent_match == NULL)
+               return true;
+
+       parent = udev_device_get_devpath(udev_enumerate->parent_match);
+       return strncmp(parent, udev_device_get_devpath(dev), strlen(parent)) == 0;
+}
+
 static bool match_sysname(struct udev_enumerate *udev_enumerate, const char *sysname)
 {
        struct udev_list_entry *list_entry;
@@ -645,6 +682,8 @@ static int scan_dir_and_add_devices(struct udev_enumerate *udev_enumerate,
                            (major(udev_device_get_devnum(dev)) > 0 || udev_device_get_ifindex(dev) > 0))
                                goto nomatch;
                }
+               if (!match_parent(udev_enumerate, dev))
+                       goto nomatch;
                if (!match_tag(udev_enumerate, dev))
                        goto nomatch;
                if (!match_property(udev_enumerate, dev))
@@ -727,78 +766,143 @@ UDEV_EXPORT int udev_enumerate_add_syspath(struct udev_enumerate *udev_enumerate
        return 0;
 }
 
-/**
- * udev_enumerate_scan_devices:
- * @udev_enumerate: udev enumeration context
- *
- * Returns: 0 on success, otherwise a negative error value.
- **/
-UDEV_EXPORT int udev_enumerate_scan_devices(struct udev_enumerate *udev_enumerate)
+static int scan_devices_tags(struct udev_enumerate *udev_enumerate)
 {
        struct udev *udev = udev_enumerate_get_udev(udev_enumerate);
-       char base[UTIL_PATH_SIZE];
-       struct stat statbuf;
-
-       if (udev_enumerate == NULL)
-               return -EINVAL;
+       struct udev_list_entry *list_entry;
 
-       if (udev_list_get_entry(&udev_enumerate->tags_match_list) != NULL) {
-               struct udev_list_entry *list_entry;
+       /* scan only tagged devices, use tags reverse-index, instead of searching all devices in /sys */
+       udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->tags_match_list)) {
+               DIR *dir;
+               struct dirent *dent;
+               char path[UTIL_PATH_SIZE];
 
-               /* scan only tagged devices, use tags reverse-index, instead of searching all devices in /sys */
-               udev_list_entry_foreach(list_entry, udev_list_get_entry(&udev_enumerate->tags_match_list)) {
-                       DIR *dir;
-                       struct dirent *dent;
-                       char path[UTIL_PATH_SIZE];
+               util_strscpyl(path, sizeof(path), udev_get_run_path(udev), "/tags/",
+                             udev_list_entry_get_name(list_entry), NULL);
+               dir = opendir(path);
+               if (dir == NULL)
+                       continue;
+               for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
+                       struct udev_device *dev;
 
-                       util_strscpyl(path, sizeof(path), udev_get_run_path(udev), "/tags/",
-                                     udev_list_entry_get_name(list_entry), NULL);
-                       dir = opendir(path);
-                       if (dir == NULL)
+                       if (dent->d_name[0] == '.')
                                continue;
-                       for (dent = readdir(dir); dent != NULL; dent = readdir(dir)) {
-                               struct udev_device *dev;
-
-                               if (dent->d_name[0] == '.')
-                                       continue;
 
-                               dev = udev_device_new_from_id_filename(udev_enumerate->udev, dent->d_name);
-                               if (dev == NULL)
-                                       continue;
+                       dev = udev_device_new_from_id_filename(udev_enumerate->udev, dent->d_name);
+                       if (dev == NULL)
+                               continue;
 
-                               if (!match_subsystem(udev_enumerate, udev_device_get_subsystem(dev)))
-                                       goto nomatch;
-                               if (!match_sysname(udev_enumerate, udev_device_get_sysname(dev)))
-                                       goto nomatch;
-                               if (!match_property(udev_enumerate, dev))
-                                       goto nomatch;
-                               if (!match_sysattr(udev_enumerate, dev))
-                                       goto nomatch;
+                       if (!match_subsystem(udev_enumerate, udev_device_get_subsystem(dev)))
+                               goto nomatch;
+                       if (!match_sysname(udev_enumerate, udev_device_get_sysname(dev)))
+                               goto nomatch;
+                       if (!match_parent(udev_enumerate, dev))
+                               goto nomatch;
+                       if (!match_property(udev_enumerate, dev))
+                               goto nomatch;
+                       if (!match_sysattr(udev_enumerate, dev))
+                               goto nomatch;
 
-                               syspath_add(udev_enumerate, udev_device_get_syspath(dev));
+                       syspath_add(udev_enumerate, udev_device_get_syspath(dev));
 nomatch:
-                               udev_device_unref(dev);
-                       }
-                       closedir(dir);
+                       udev_device_unref(dev);
                }
+               closedir(dir);
+       }
+       return 0;
+}
+
+static int parent_add_child(struct udev_enumerate *enumerate, const char *path)
+{
+       struct udev_device *dev;
+
+       dev = udev_device_new_from_syspath(enumerate->udev, path);
+       if (dev == NULL)
+               return -ENODEV;
+
+       if (!match_subsystem(enumerate, udev_device_get_subsystem(dev)))
+               return 0;
+       if (!match_sysname(enumerate, udev_device_get_sysname(dev)))
+               return 0;
+       if (!match_property(enumerate, dev))
+               return 0;
+       if (!match_sysattr(enumerate, dev))
+               return 0;
+
+       syspath_add(enumerate, udev_device_get_syspath(dev));
+       udev_device_unref(dev);
+       return 1;
+}
+
+static int parent_crawl_children(struct udev_enumerate *enumerate, const char *path, int maxdepth)
+{
+       DIR *d;
+       struct dirent *dent;
+
+       d = opendir(path);
+       if (d == NULL)
+               return -errno;
+
+       for (dent = readdir(d); dent != NULL; dent = readdir(d)) {
+               char *child;
+
+               if (dent->d_name[0] == '.')
+                       continue;
+               if (dent->d_type != DT_DIR)
+                       continue;
+               if (asprintf(&child, "%s/%s", path, dent->d_name) < 0)
+                       continue;
+               parent_add_child(enumerate, child);
+               if (maxdepth > 0)
+                       parent_crawl_children(enumerate, child, maxdepth-1);
+               free(child);
+       }
+
+       closedir(d);
+       return 0;
+}
+
+static int scan_devices_all(struct udev_enumerate *udev_enumerate)
+{
+       struct udev *udev = udev_enumerate_get_udev(udev_enumerate);
+       char base[UTIL_PATH_SIZE];
+       struct stat statbuf;
+
+       util_strscpyl(base, sizeof(base), udev_get_sys_path(udev), "/subsystem", NULL);
+       if (stat(base, &statbuf) == 0) {
+               /* we have /subsystem/, forget all the old stuff */
+               dbg(udev, "searching '/subsystem/*/devices/*' dir\n");
+               scan_dir(udev_enumerate, "subsystem", "devices", NULL);
        } else {
-               util_strscpyl(base, sizeof(base), udev_get_sys_path(udev), "/subsystem", NULL);
-               if (stat(base, &statbuf) == 0) {
-                       /* we have /subsystem/, forget all the old stuff */
-                       dbg(udev, "searching '/subsystem/*/devices/*' dir\n");
-                       scan_dir(udev_enumerate, "subsystem", "devices", NULL);
-               } else {
                dbg(udev, "searching '/bus/*/devices/*' dir\n");
-                       scan_dir(udev_enumerate, "bus", "devices", NULL);
-                       dbg(udev, "searching '/class/*' dir\n");
-                       scan_dir(udev_enumerate, "class", NULL, NULL);
-               }
+               scan_dir(udev_enumerate, "bus", "devices", NULL);
+               dbg(udev, "searching '/class/*' dir\n");
+               scan_dir(udev_enumerate, "class", NULL, NULL);
        }
-
        return 0;
 }
 
 /**
+ * udev_enumerate_scan_devices:
+ * @udev_enumerate: udev enumeration context
+ *
+ * Returns: 0 on success, otherwise a negative error value.
+ **/
+UDEV_EXPORT int udev_enumerate_scan_devices(struct udev_enumerate *udev_enumerate)
+{
+       if (udev_enumerate == NULL)
+               return -EINVAL;
+
+       if (udev_list_get_entry(&udev_enumerate->tags_match_list) != NULL)
+               return scan_devices_tags(udev_enumerate);
+
+       if (udev_enumerate->parent_match != NULL)
+               return parent_crawl_children(udev_enumerate, udev_device_get_syspath(udev_enumerate->parent_match), 256);
+
+       return scan_devices_all(udev_enumerate);
+}
+
+/**
  * udev_enumerate_scan_subsystems:
  * @udev_enumerate: udev enumeration context
  *
index 1d4a4ae..d8eb7df 100644 (file)
@@ -146,6 +146,7 @@ int udev_enumerate_add_nomatch_sysattr(struct udev_enumerate *udev_enumerate, co
 int udev_enumerate_add_match_property(struct udev_enumerate *udev_enumerate, const char *property, const char *value);
 int udev_enumerate_add_match_sysname(struct udev_enumerate *udev_enumerate, const char *sysname);
 int udev_enumerate_add_match_tag(struct udev_enumerate *udev_enumerate, const char *tag);
+int udev_enumerate_add_match_parent(struct udev_enumerate *udev_enumerate, struct udev_device *parent);
 int udev_enumerate_add_match_is_initialized(struct udev_enumerate *udev_enumerate);
 int udev_enumerate_add_syspath(struct udev_enumerate *udev_enumerate, const char *syspath);
 /* run enumeration with active filters */
index d31b4fb..3b53be5 100644 (file)
@@ -103,6 +103,7 @@ int udevadm_trigger(struct udev *udev, int argc, char *argv[])
                { "property-match", required_argument, NULL, 'p' },
                { "tag-match", required_argument, NULL, 'g' },
                { "sysname-match", required_argument, NULL, 'y' },
+               { "parent-match", required_argument, NULL, 'b' },
                { "help", no_argument, NULL, 'h' },
                {}
        };
@@ -128,7 +129,7 @@ int udevadm_trigger(struct udev *udev, int argc, char *argv[])
                const char *val;
                char buf[UTIL_PATH_SIZE];
 
-               option = getopt_long(argc, argv, "vng:o:t:hc:p:s:S:a:A:y:", options, NULL);
+               option = getopt_long(argc, argv, "vng:o:t:hc:p:s:S:a:A:y:b:", options, NULL);
                if (option == -1)
                        break;
 
@@ -179,6 +180,27 @@ int udevadm_trigger(struct udev *udev, int argc, char *argv[])
                case 'y':
                        udev_enumerate_add_match_sysname(udev_enumerate, optarg);
                        break;
+               case 'b': {
+                       char path[UTIL_PATH_SIZE];
+                       struct udev_device *dev;
+
+                       /* add sys dir if needed */
+                       if (strncmp(optarg, udev_get_sys_path(udev), strlen(udev_get_sys_path(udev))) != 0)
+                               util_strscpyl(path, sizeof(path), udev_get_sys_path(udev), optarg, NULL);
+                       else
+                               util_strscpy(path, sizeof(path), optarg);
+                       util_remove_trailing_chars(path, '/');
+                       dev = udev_device_new_from_syspath(udev, path);
+                       if (dev == NULL) {
+                               err(udev, "unable to open the device '%s'\n", optarg);
+                               rc = 2;
+                               goto exit;
+                       }
+                       udev_enumerate_add_match_parent(udev_enumerate, dev);
+                       /* drop reference immediately, enumerate pins the device as long as needed */
+                       udev_device_unref(dev);
+                       break;
+               }
                case 'h':
                        printf("Usage: udevadm trigger OPTIONS\n"
                               "  --verbose                       print the list of devices while running\n"
@@ -196,6 +218,7 @@ int udevadm_trigger(struct udev *udev, int argc, char *argv[])
                               "  --property-match=<key>=<value>  trigger devices with a matching property\n"
                               "  --tag-match=<key>=<value>       trigger devices with a matching property\n"
                               "  --sysname-match=<name>          trigger devices with a matching name\n"
+                              "  --parent-match=<name>           trigger devices with that parent device\n"
                               "  --help\n\n");
                        goto exit;
                default:
index b5fb971..a106093 100644 (file)
             specified multiple times and supports shell style pattern matching.</para>
           </listitem>
         </varlistentry>
+        <varlistentry>
+          <term><option>--parent-match=<replaceable>syspath</replaceable></option></term>
+          <listitem>
+            <para>Trigger events for all children of a given device.</para>
+          </listitem>
+        </varlistentry>
       </variablelist>
     </refsect2>