chiark / gitweb /
[PATCH] udev - drop all methods :)
[elogind.git] / libsysfs / sysfs_device.c
index fbd046f..66d5f9a 100644 (file)
 #include "libsysfs.h"
 #include "sysfs.h"
 
-static int confirm_device_bus(struct sysfs_device *dev, 
-                               unsigned char *busname, unsigned char *bus_id)
-{
-        struct sysfs_link *devlink = NULL;
-        unsigned char devpath[SYSFS_PATH_MAX];
-       int result = 0;
-
-        if (busname == NULL || bus_id == NULL)
-                return -1;
-
-        if (sysfs_get_mnt_path(devpath, SYSFS_PATH_MAX) != 0)
-                return -1;
-
-        strcat(devpath, SYSFS_BUS_DIR);
-        strcat(devpath, "/");
-        strcat(devpath, busname);
-        strcat(devpath, SYSFS_DEVICES_DIR);
-        strcat(devpath, "/");
-        strcat(devpath, bus_id);
-
-       devlink = sysfs_open_link(devpath);
-       if (devlink == NULL)
-               return -1;
-
-       if (strcmp(devlink->target, dev->path) == 0)
-               result++;
-       sysfs_close_link(devlink);
-       return result;
-}
-
 /**
  * get_device_bus: retrieves the bus name the device is on, checks path to
  *     bus' link to make sure it has correct device.
@@ -61,33 +31,53 @@ static int confirm_device_bus(struct sysfs_device *dev,
  */
 static int get_device_bus(struct sysfs_device *dev)
 {
-       unsigned char subsys[SYSFS_NAME_LEN], *bus = NULL, *curdev = NULL;
-       struct dlist *buslist = NULL, *device_list = NULL;
+       unsigned char subsys[SYSFS_NAME_LEN], path[SYSFS_PATH_MAX];
+       unsigned char target[SYSFS_PATH_MAX], *bus = NULL, *c = NULL;
+       struct dlist *buslist = NULL;
 
        if (dev == NULL) {
                errno = EINVAL;
                return -1;
        }
 
-       strcpy(subsys, SYSFS_BUS_DIR);  /* subsys = /bus */
+       memset(subsys, 0, SYSFS_NAME_LEN);
+       strcat(subsys, "/");
+       strcpy(subsys, SYSFS_BUS_NAME);  /* subsys = /bus */
        buslist = sysfs_open_subsystem_list(subsys);
        if (buslist != NULL) {
                dlist_for_each_data(buslist, bus, char) {
-                       device_list = sysfs_open_bus_devices_list(bus);
-                       if (device_list != NULL) {
-                               dlist_for_each_data(device_list,
-                                                       curdev, char) {
-                                       if (strcmp(dev->bus_id, curdev) == 0
-                                           && confirm_device_bus(dev, bus,
-                                           curdev) > 0) {
-                                               strcpy(dev->bus, bus);
-                                                sysfs_close_list(device_list);
-                                                sysfs_close_list(buslist);
-                                                return 0;
-                                        }
-                                }
-                        sysfs_close_list(device_list);
-                        }
+                       memset(path, 0, SYSFS_PATH_MAX);
+                       strcpy(path, dev->path);
+                       c = strstr(path, "/devices");
+                       if (c == NULL) {
+                               dprintf("Invalid path to device %s\n", path);
+                               sysfs_close_list(buslist);
+                               return -1;
+                       }
+                       *c = '\0';
+                       strcat(path, "/");
+                       strcat(path, SYSFS_BUS_NAME);
+                       strcat(path, "/");
+                       strcat(path, bus);
+                       strcat(path, "/");
+                       strcat(path, SYSFS_DEVICES_NAME);
+                       strcat(path, "/");
+                       strcat(path, dev->bus_id);
+                       if ((sysfs_path_is_link(path)) == 0) {
+                               memset(target, 0, SYSFS_PATH_MAX);
+                               if ((sysfs_get_link(path, target, 
+                                                       SYSFS_PATH_MAX)) != 0) {
+                                       dprintf("Error getting link target\n");
+                                       sysfs_close_list(buslist);
+                                       return -1;
+                               }
+                               if (!(strncmp(target, dev->path, 
+                                                       SYSFS_PATH_MAX))) {
+                                       strcpy(dev->bus, bus);
+                                       sysfs_close_list(buslist);
+                                       return 0;
+                               }
+                       }
                 }
                 sysfs_close_list(buslist);
         }
@@ -115,14 +105,6 @@ static void sysfs_close_device_tree(struct sysfs_device *devroot)
 }
 
 /**
- * sysfs_del_device: routine for dlist integration
- */
-static void sysfs_del_device(void *dev)
-{
-       sysfs_close_device((struct sysfs_device *)dev);
-}
-
-/**
  * sysfs_close_dev_tree: routine for dlist integration
  */
 static void sysfs_close_dev_tree(void *dev)
@@ -137,6 +119,8 @@ static void sysfs_close_dev_tree(void *dev)
 void sysfs_close_device(struct sysfs_device *dev)
 {
        if (dev != NULL) {
+               if (dev->parent != NULL)
+                       sysfs_close_device(dev->parent);
                if (dev->directory != NULL)
                        sysfs_close_directory(dev->directory);
                if (dev->children != NULL && dev->children->count == 0)
@@ -155,72 +139,70 @@ static struct sysfs_device *alloc_device(void)
 }
 
 /**
- * sysfs_get_device_attr: searches dev's attributes by name
- * @dev: device to look through
- * @name: attribute name to get
- * returns sysfs_attribute reference with success or NULL with error.
+ * open_device_dir: opens up sysfs_directory for specific root dev
+ * @name: name of root
+ * returns struct sysfs_directory with success and NULL with error
  */
-struct sysfs_attribute *sysfs_get_device_attr(struct sysfs_device *dev,
-                                               const unsigned char *name)
+static struct sysfs_directory *open_device_dir(const unsigned char *path)
 {
-       struct sysfs_attribute *cur = NULL;
+       struct sysfs_directory *rdir = NULL;
 
-       if (dev == NULL || dev->directory == NULL 
-           || dev->directory->attributes == NULL || name == NULL) {
+       if (path == NULL) {
                errno = EINVAL;
                return NULL;
        }
-       
-       cur = sysfs_get_directory_attribute(dev->directory, 
-                       (unsigned char *)name);
-       if (cur != NULL)
-               return cur;
 
-       return NULL;
+       rdir = sysfs_open_directory(path);
+       if (rdir == NULL) {
+               errno = EINVAL;
+               dprintf ("Device %s not supported on this system\n", path);
+               return NULL;
+       }
+       if ((sysfs_read_dir_subdirs(rdir)) != 0) {
+               dprintf ("Error reading device at dir %s\n", path);
+               sysfs_close_directory(rdir);
+               return NULL;
+       }
+       
+       return rdir;
 }
 
 /**
- * sysfs_open_device: opens and populates device structure
+ * sysfs_open_device_path: opens and populates device structure
  * @path: path to device, this is the /sys/devices/ path
  * returns sysfs_device structure with success or NULL with error
  */
-struct sysfs_device *sysfs_open_device(const unsigned char *path)
+struct sysfs_device *sysfs_open_device_path(const unsigned char *path)
 {
        struct sysfs_device *dev = NULL;
-       struct sysfs_directory *sdir = NULL;
 
        if (path == NULL) {
                errno = EINVAL;
                return NULL;
        }
+       if ((sysfs_path_is_dir(path)) != 0) {
+               dprintf("Incorrect path to device: %s\n", path);
+               return NULL;
+       }
        dev = alloc_device();   
        if (dev == NULL) {
                dprintf("Error allocating device at %s\n", path);
                return NULL;
        }
-       sdir = sysfs_open_directory(path);
-       if (sdir == NULL) {
-               dprintf("Invalid device at %s\n", path);
+       if ((sysfs_get_name_from_path(path, dev->bus_id, 
+                                       SYSFS_NAME_LEN)) != 0) {
                errno = EINVAL;
+               dprintf("Error getting device bus_id\n");
                sysfs_close_device(dev);
                return NULL;
        }
-       if ((sysfs_read_directory(sdir)) != 0) {
-               dprintf("Error reading device directory at %s\n", path);
-               sysfs_close_directory(sdir);
-               sysfs_close_device(dev);
-               return NULL;
-       }
-       dev->directory = sdir;
-       strcpy(dev->bus_id, sdir->name);
-       strcpy(dev->path, sdir->path);
-
+       strcpy(dev->path, path);
        /* 
         * The "name" attribute no longer exists... return the device's
         * sysfs representation instead, in the "dev->name" field, which
         * implies that the dev->name and dev->bus_id contain same data.
         */
-       strncpy(dev->name, sdir->name, SYSFS_NAME_LEN);
+       strncpy(dev->name, dev->bus_id, SYSFS_NAME_LEN);
        
        if (get_device_bus(dev) != 0)
                strcpy(dev->bus, SYSFS_UNKNOWN);
@@ -244,11 +226,16 @@ static struct sysfs_device *sysfs_open_device_tree(const unsigned char *path)
                errno = EINVAL;
                return NULL;
        }
-       rootdev = sysfs_open_device(path);
+       rootdev = sysfs_open_device_path(path);
        if (rootdev == NULL) {
                dprintf("Error opening root device at %s\n", path);
                return NULL;
        }
+       if (rootdev->directory == NULL) {
+               rootdev->directory = open_device_dir(rootdev->path);
+               if (rootdev->directory == NULL) 
+                       return NULL;
+       }
        if (rootdev->directory->subdirs != NULL) {
                dlist_for_each_data(rootdev->directory->subdirs, cur,
                                struct sysfs_directory) {
@@ -262,7 +249,7 @@ static struct sysfs_device *sysfs_open_device_tree(const unsigned char *path)
                        if (rootdev->children == NULL)
                                rootdev->children = dlist_new_with_delete
                                        (sizeof(struct sysfs_device),
-                                       sysfs_del_device);
+                                       sysfs_close_dev_tree);
                        dlist_unshift(rootdev->children, new);
                }
        }
@@ -286,60 +273,25 @@ void sysfs_close_root_device(struct sysfs_root_device *root)
 }
 
 /**
- * open_root_device_dir: opens up sysfs_directory for specific root dev
- * @name: name of root
- * returns struct sysfs_directory with success and NULL with error
- */
-static struct sysfs_directory *open_root_device_dir(const unsigned char *name)
-{
-       struct sysfs_directory *rdir = NULL;
-       unsigned char rootpath[SYSFS_PATH_MAX];
-
-       if (name == NULL) {
-               errno = EINVAL;
-               return NULL;
-       }
-
-       memset(rootpath, 0, SYSFS_PATH_MAX);
-       if (sysfs_get_mnt_path(rootpath, SYSFS_PATH_MAX) != 0) {
-               dprintf ("Sysfs not supported on this system\n");
-               return NULL;
-       }
-
-       strcat(rootpath, SYSFS_DEVICES_DIR);
-       strcat(rootpath, "/");
-       strcat(rootpath, name);
-       rdir = sysfs_open_directory(rootpath);
-       if (rdir == NULL) {
-               errno = EINVAL;
-               dprintf ("Root device %s not supported on this system\n",
-                       name);
-               return NULL;
-       }
-       if (sysfs_read_directory(rdir) != 0) {
-               dprintf ("Error reading %s root device at dir %s\n", name,
-                       rootpath);
-               sysfs_close_directory(rdir);
-               return NULL;
-       }
-       
-       return rdir;
-}
-
-/**
- * get_all_root_devices: opens up all the devices under this root device
+ * sysfs_get_root_devices: opens up all the devices under this root device
  * @root: root device to open devices for
- * returns 0 with success and -1 with error
+ * returns dlist of devices with success and NULL with error
  */
-static int get_all_root_devices(struct sysfs_root_device *root)
+struct dlist *sysfs_get_root_devices(struct sysfs_root_device *root)
 {
        struct sysfs_device *dev = NULL;
        struct sysfs_directory *cur = NULL;
 
-       if (root == NULL || root->directory == NULL) {
+       if (root == NULL) {
                errno = EINVAL;
-               return -1;
+               return NULL;
+       }
+       if (root->directory == NULL) {
+               root->directory = open_device_dir(root->path);
+               if (root->directory == NULL)
+                       return NULL;
        }
+               
        if (root->directory->subdirs == NULL)
                return 0;
 
@@ -357,7 +309,7 @@ static int get_all_root_devices(struct sysfs_root_device *root)
                dlist_unshift(root->devices, dev);
        }
 
-       return 0;
+       return root->devices;
 }
 
 /**
@@ -369,33 +321,37 @@ static int get_all_root_devices(struct sysfs_root_device *root)
 struct sysfs_root_device *sysfs_open_root_device(const unsigned char *name)
 {
        struct sysfs_root_device *root = NULL;
-       struct sysfs_directory *rootdir = NULL;
+       unsigned char rootpath[SYSFS_PATH_MAX];
 
        if (name == NULL) {
                errno = EINVAL;
                return NULL;
        }
 
-       root = (struct sysfs_root_device *)calloc
-                                       (1, sizeof(struct sysfs_root_device));
-       if (root == NULL) {
-               dprintf("calloc failure\n");
+       memset(rootpath, 0, SYSFS_PATH_MAX);
+       if (sysfs_get_mnt_path(rootpath, SYSFS_PATH_MAX) != 0) {
+               dprintf ("Sysfs not supported on this system\n");
                return NULL;
        }
-       rootdir = open_root_device_dir(name);
-       if (rootdir == NULL) {
-               dprintf ("Invalid root device, %s not supported\n", name);
-               sysfs_close_root_device(root);
+
+       if (sysfs_trailing_slash(rootpath) == 0)
+               strcat(rootpath, "/");
+       strcat(rootpath, SYSFS_DEVICES_NAME);
+       strcat(rootpath, "/");
+       strcat(rootpath, name);
+       if ((sysfs_path_is_dir(rootpath)) != 0) {
+               errno = EINVAL;
+               dprintf("Invalid root device: %s\n", name);
                return NULL;
        }
-       strcpy(root->path, rootdir->path);
-       root->directory = rootdir;
-       if (get_all_root_devices(root) != 0) {
-               dprintf ("Error retrieving devices for root %s\n", name);
-               sysfs_close_root_device(root);
+       root = (struct sysfs_root_device *)calloc
+                                       (1, sizeof(struct sysfs_root_device));
+       if (root == NULL) {
+               dprintf("calloc failure\n");
                return NULL;
        }
-
+       strcpy(root->name, name);
+       strcpy(root->path, rootpath);
        return root;
 }
 
@@ -406,13 +362,59 @@ struct sysfs_root_device *sysfs_open_root_device(const unsigned char *name)
  */
 struct dlist *sysfs_get_device_attributes(struct sysfs_device *device)
 {
-       if (device == NULL || device->directory == NULL
+       if (device == NULL) 
                return NULL;
 
+       if (device->directory == NULL) {
+               device->directory = sysfs_open_directory(device->path);
+               if (device->directory == NULL) 
+                       return NULL;
+       }
+       if (device->directory->attributes == NULL) {
+               if ((sysfs_read_dir_attributes(device->directory)) != 0)
+                       return NULL;
+       } else {
+               if ((sysfs_path_is_dir(device->path)) != 0) {
+                       dprintf("Device at %s no longer exists", device->path);
+                       return NULL;
+               }
+               if ((sysfs_refresh_attributes
+                               (device->directory->attributes)) != 0) {
+                       dprintf("Error refreshing device attributes\n");
+                       return NULL;
+               }
+       }
        return (device->directory->attributes);
 }
 
 /**
+ * sysfs_get_device_attr: searches dev's attributes by name
+ * @dev: device to look through
+ * @name: attribute name to get
+ * returns sysfs_attribute reference with success or NULL with error.
+ */
+struct sysfs_attribute *sysfs_get_device_attr(struct sysfs_device *dev,
+                                               const unsigned char *name)
+{
+       struct sysfs_attribute *cur = NULL;
+       struct dlist *attrlist = NULL;
+
+       if (dev == NULL || name == NULL) {
+               errno = EINVAL;
+               return NULL;
+       }
+
+       attrlist = sysfs_get_device_attributes(dev);
+       if (attrlist == NULL)
+               return NULL;
+
+       cur = sysfs_get_directory_attribute(dev->directory, 
+                       (unsigned char *)name);
+
+       return cur;
+}
+
+/**
  * get_device_absolute_path: looks up the bus the device is on, gets 
  *             absolute path to the device
  * @device: device for which path is needed
@@ -423,22 +425,25 @@ struct dlist *sysfs_get_device_attributes(struct sysfs_device *device)
 static int get_device_absolute_path(const unsigned char *device,
                const unsigned char *bus, unsigned char *path, size_t psize)
 {
-       unsigned char bus_path[SYSFS_NAME_LEN];
+       unsigned char bus_path[SYSFS_PATH_MAX];
 
        if (device == NULL || path == NULL) {
                errno = EINVAL;
                return -1;
        }
 
-       memset(bus_path, 0, SYSFS_NAME_LEN);
+       memset(bus_path, 0, SYSFS_PATH_MAX);
        if (sysfs_get_mnt_path(bus_path, SYSFS_PATH_MAX) != 0) {
                dprintf ("Sysfs not supported on this system\n");
                return -1;
        }
-       strcat(bus_path, SYSFS_BUS_DIR);
+       if (sysfs_trailing_slash(bus_path) == 0)
+               strcat(bus_path, "/");
+       strcat(bus_path, SYSFS_BUS_NAME);
        strcat(bus_path, "/");
        strcat(bus_path, bus);
-       strcat(bus_path, SYSFS_DEVICES_DIR);
+       strcat(bus_path, "/");
+       strcat(bus_path, SYSFS_DEVICES_NAME);
        strcat(bus_path, "/");
        strcat(bus_path, device);
        /*
@@ -453,19 +458,18 @@ static int get_device_absolute_path(const unsigned char *device,
 }
 
 /**
- * sysfs_open_device_by_id: open a device by id (use the "bus" subsystem)
+ * sysfs_open_device: open a device by id (use the "bus" subsystem)
  * @bus_id: bus_id of the device to open - has to be the "bus_id" in 
  *             /sys/bus/xxx/devices
  * @bus: bus the device belongs to
- * @bsize: size of the bus buffer
  * returns struct sysfs_device if found, NULL otherwise
  * NOTE: 
  * 1. Use sysfs_close_device to close the device
  * 2. Bus the device is on must be supplied
  *     Use sysfs_find_device_bus to get the bus name
  */
-struct sysfs_device *sysfs_open_device_by_id(const unsigned char *bus_id, 
-               const unsigned char *bus, size_t bsize)
+struct sysfs_device *sysfs_open_device(const unsigned char *bus_id, 
+                                               const unsigned char *bus)
 {
        char sysfs_path[SYSFS_PATH_MAX];
        struct sysfs_device *device = NULL;
@@ -481,7 +485,7 @@ struct sysfs_device *sysfs_open_device_by_id(const unsigned char *bus_id,
                return NULL;
        }
        
-       device = sysfs_open_device(sysfs_path);
+       device = sysfs_open_device_path(sysfs_path);
        if (device == NULL) {
                dprintf("Error opening device %s\n", bus_id);
                return NULL;
@@ -490,6 +494,60 @@ struct sysfs_device *sysfs_open_device_by_id(const unsigned char *bus_id,
        return device;
 }
 
+/**
+ * sysfs_get_device_parent: opens up given device's parent and returns a 
+ *     reference to its sysfs_device
+ * @dev: sysfs_device whose parent is requested
+ * Returns sysfs_device of the parent on success and NULL on failure
+ */
+struct sysfs_device *sysfs_get_device_parent(struct sysfs_device *dev)
+{
+       unsigned char ppath[SYSFS_PATH_MAX], *tmp = NULL;
+
+       if (dev == NULL) {
+               errno = EINVAL;
+               return NULL;
+       }
+
+       if (dev->parent != NULL)
+               return (dev->parent);
+
+       memset(ppath, 0, SYSFS_PATH_MAX);
+       strcpy(ppath, dev->path);
+       tmp = strrchr(ppath, '/');
+       if (tmp == NULL) {
+               dprintf("Invalid path to device %s\n", ppath);
+               return NULL;
+       }
+       if (*(tmp +1) == '\0') {
+               *tmp = '\0';
+               tmp = strrchr(tmp, '/');
+               if (tmp == NULL) {
+                       dprintf("Invalid path to device %s\n", ppath);
+                       return NULL;
+               }
+       }
+       *tmp = '\0';
+       
+       /*
+        * All "devices" have the "detach_state" attribute - validate here
+        */
+       strcat(ppath, "/detach_state");
+       if ((sysfs_path_is_file(ppath)) != 0) {
+               dprintf("Device at %s does not have a parent\n", dev->path);
+               return NULL;
+       }
+       tmp = strrchr(ppath, '/');
+       *tmp = '\0';
+       dev->parent = sysfs_open_device_path(ppath);
+       if (dev->parent == NULL) {
+               dprintf("Error opening device %s's parent at %s\n", 
+                                       dev->bus_id, ppath);
+               return NULL;
+       }
+       return (dev->parent);
+}
+
 /*
  * sysfs_open_device_attr: open the given device's attribute
  * @bus: Bus on which to look