/*
- * udev_sysfs.c - sysfs linux kernel specific knowledge
- *
- * Copyright (C) 2004 Kay Sievers <kay.sievers@vrfy.org>
- * Copyright (C) 2004 Greg Kroah-Hartman <greg@kroah.com>
+ * Copyright (C) 2005-2006 Kay Sievers <kay.sievers@vrfy.org>
*
* This program is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License as published by the
*
* You should have received a copy of the GNU General Public License along
* with this program; if not, write to the Free Software Foundation, Inc.,
- * 675 Mass Ave, Cambridge, MA 02139, USA.
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*
*/
+
+#include <stdlib.h>
#include <stdio.h>
#include <stddef.h>
-#include <stdlib.h>
#include <unistd.h>
-#include <string.h>
+#include <fcntl.h>
#include <ctype.h>
#include <errno.h>
#include <sys/stat.h>
-#include "libsysfs/sysfs/libsysfs.h"
-#include "udev_version.h"
-#include "udev_sysfs.h"
-#include "udev_utils.h"
-#include "logging.h"
+#include "udev.h"
-/* list of subsystem specific files, NULL if there is no file to wait for */
-dev_t get_devt(struct sysfs_class_device *class_dev)
-{
- struct sysfs_attribute *attr = NULL;
- unsigned int major, minor;
+char sysfs_path[PATH_SIZE];
- attr = sysfs_get_classdev_attr(class_dev, "dev");
- if (attr == NULL)
- return 0;
- dbg("dev='%s'", attr->value);
+/* device cache */
+static LIST_HEAD(dev_list);
- if (sscanf(attr->value, "%u:%u", &major, &minor) != 2)
- return 0;
- dbg("found major=%d, minor=%d", major, minor);
+/* attribute value cache */
+static LIST_HEAD(attr_list);
+struct sysfs_attr {
+ struct list_head node;
+ char path[PATH_SIZE];
+ char *value; /* points to value_local if value is cached */
+ char value_local[NAME_SIZE];
+};
- return makedev(major, minor);
+int sysfs_init(void)
+{
+ const char *env;
+
+ env = getenv("SYSFS_PATH");
+ if (env) {
+ strlcpy(sysfs_path, env, sizeof(sysfs_path));
+ remove_trailing_chars(sysfs_path, '/');
+ } else
+ strlcpy(sysfs_path, "/sys", sizeof(sysfs_path));
+ dbg("sysfs_path='%s'", sysfs_path);
+
+ INIT_LIST_HEAD(&dev_list);
+ INIT_LIST_HEAD(&attr_list);
+ return 0;
}
-/* wait for a devices device specific file to show up */
-int wait_for_devices_device(struct sysfs_device *devices_dev,
- const char **error)
+void sysfs_cleanup(void)
{
- static const struct device_file {
- const char *bus;
- const char *file;
- } device_files[] = {
- { .bus = "scsi", .file = "vendor" },
- { .bus = "usb", .file = "idVendor" },
- { .bus = "usb", .file = "iInterface" },
- { .bus = "usb", .file = "bNumEndpoints" },
- { .bus = "usb-serial", .file = "bus" },
- { .bus = "ide", .file = "bus" },
- { .bus = "pci", .file = "vendor" },
- { .bus = "pci_express", .file = "bus" },
- { .bus = "platform", .file = "bus" },
- { .bus = "pcmcia", .file = "bus" },
- { .bus = "i2c", .file = "bus" },
- { .bus = "ieee1394", .file = "node_count" },
- { .bus = "ieee1394", .file = "nodeid" },
- { .bus = "ieee1394", .file = "address" },
- { .bus = "bttv-sub", .file = NULL },
- { .bus = "pnp", .file = "bus" },
- { .bus = "eisa", .file = "bus" },
- { .bus = "serio", .file = "bus" },
- { .bus = "pseudo", .file = "bus" },
- { .bus = "mmc", .file = "bus" },
- { .bus = "macio", .file = "bus" },
- { .bus = "of_platform", .file = "bus" },
- { .bus = "vio", .file = "bus" },
- { .bus = "ecard", .file = "bus" },
- { .bus = "sa1111-rab", .file = "bus" },
- { .bus = "amba", .file = "bus" },
- { .bus = "locomo-bus", .file = "bus" },
- { .bus = "logicmodule", .file = "bus" },
- { .bus = "parisc", .file = "bus" },
- { .bus = "ocp", .file = "bus" },
- { .bus = "dio", .file = "bus" },
- { .bus = "MCA", .file = "bus" },
- { .bus = "wl", .file = "bus" },
- { .bus = "ccwgroup", .file = "bus" },
- { .bus = "css", .file = "bus" },
- { .bus = "ccw", .file = "bus" },
- { .bus = "iucv", .file = "bus" },
- { NULL, NULL }
- };
- const struct device_file *devicefile = NULL;
- int loop;
-
- if (getenv("PHYSDEVBUS") == NULL) {
- dbg("the kernel says, that there is no bus for '%s'", devices_dev->path);
- return 0;
+ struct sysfs_attr *attr_loop;
+ struct sysfs_attr *attr_temp;
+ struct sysfs_device *dev_loop;
+ struct sysfs_device *dev_temp;
+
+ list_for_each_entry_safe(attr_loop, attr_temp, &attr_list, node) {
+ list_del(&attr_loop->node);
+ free(attr_loop);
}
- /* wait for the bus device link to the devices device */
- loop = WAIT_MAX_SECONDS * WAIT_LOOP_PER_SECOND;
- while (--loop) {
- if (sysfs_get_device_bus(devices_dev) == 0)
- break;
-
- usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND);
- }
- if (loop == 0) {
- dbg("error: getting bus device link");
- if (error)
- *error = "no bus device link";
- return -1;
+ list_for_each_entry_safe(dev_loop, dev_temp, &dev_list, node) {
+ list_del(&dev_loop->node);
+ free(dev_loop);
}
- dbg("bus device link found for bus '%s'", devices_dev->bus);
-
- /* wait for a bus device specific file to show up */
- loop = WAIT_MAX_SECONDS * WAIT_LOOP_PER_SECOND;
- while (--loop) {
- int found_bus_type = 0;
-
- for (devicefile = device_files; devicefile->bus != NULL; devicefile++) {
- if (strcmp(devices_dev->bus, devicefile->bus) == 0) {
- char filename[PATH_SIZE];
- struct stat stats;
-
- if (devicefile->file == NULL) {
- dbg("bus '%s' has no file to wait for", devices_dev->bus);
- return 0;
- }
-
- found_bus_type = 1;
- snprintf(filename, sizeof(filename), "%s/%s", devices_dev->path, devicefile->file);
- filename[sizeof(filename)-1] = '\0';
- dbg("looking at bus '%s' device for specific file '%s'", devices_dev->bus, filename);
-
- if (stat(filename, &stats) == 0) {
- dbg("bus '%s' device specific file '%s' found", devices_dev->bus, devicefile->file);
- return 0;
- }
- }
- }
- if (found_bus_type == 0) {
- if (error)
- *error = "unknown bus";
- info("error: unknown bus, please report to "
- "<linux-hotplug-devel@lists.sourceforge.net> '%s'", devices_dev->bus);
- return -1;
- }
- usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND);
+}
+
+void sysfs_device_set_values(struct sysfs_device *dev, const char *devpath,
+ const char *subsystem, const char *driver)
+{
+ char *pos;
+
+ strlcpy(dev->devpath, devpath, sizeof(dev->devpath));
+ if (subsystem != NULL)
+ strlcpy(dev->subsystem, subsystem, sizeof(dev->subsystem));
+ if (driver != NULL)
+ strlcpy(dev->driver, driver, sizeof(dev->driver));
+
+ /* set kernel name */
+ pos = strrchr(dev->devpath, '/');
+ if (pos == NULL)
+ return;
+
+ strlcpy(dev->kernel, &pos[1], sizeof(dev->kernel));
+ dbg("kernel='%s'", dev->kernel);
+
+ /* some devices have '!' in their name, change that to '/' */
+ pos = dev->kernel;
+ while (pos[0] != '\0') {
+ if (pos[0] == '!')
+ pos[0] = '/';
+ pos++;
}
- dbg("error: getting '%s' device specific file '%s'", devices_dev->bus, devicefile->file);
- if (error)
- *error = "bus device specific file unavailable";
- return -1;
+ /* get kernel number */
+ pos = &dev->kernel[strlen(dev->kernel)];
+ while (isdigit(pos[-1]))
+ pos--;
+ strlcpy(dev->kernel_number, pos, sizeof(dev->kernel_number));
+ dbg("kernel_number='%s'", dev->kernel_number);
}
-
-struct sysfs_class_device *wait_class_device_open(const char *path)
+int sysfs_resolve_link(char *devpath, size_t size)
{
- struct sysfs_class_device *class_dev = NULL;
- int loop;
+ char link_path[PATH_SIZE];
+ char link_target[PATH_SIZE];
+ int len;
+ int i;
+ int back;
+
+ strlcpy(link_path, sysfs_path, sizeof(link_path));
+ strlcat(link_path, devpath, sizeof(link_path));
+ len = readlink(link_path, link_target, sizeof(link_target));
+ if (len <= 0)
+ return -1;
+ link_target[len] = '\0';
+ dbg("path link '%s' points to '%s'", devpath, link_target);
- loop = WAIT_MAX_SECONDS * WAIT_LOOP_PER_SECOND;
- while (--loop) {
- class_dev = sysfs_open_class_device_path(path);
- if (class_dev)
- break;
+ for (back = 0; strncmp(&link_target[back * 3], "../", 3) == 0; back++)
+ ;
+ dbg("base '%s', tail '%s', back %i", devpath, &link_target[back * 3], back);
+ for (i = 0; i <= back; i++) {
+ char *pos = strrchr(devpath, '/');
- usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND);
+ if (pos == NULL)
+ return -1;
+ pos[0] = '\0';
}
-
- return class_dev;
+ dbg("after moving back '%s'", devpath);
+ strlcat(devpath, "/", size);
+ strlcat(devpath, &link_target[back * 3], size);
+ return 0;
}
-int wait_for_class_device(struct sysfs_class_device *class_dev,
- const char **error)
+struct sysfs_device *sysfs_device_get(const char *devpath)
{
- const struct subsystem_file {
- const char *subsystem;
- const char *file;
- } subsystem_files[] = {
- { .subsystem = "net", .file = "ifindex" },
- { .subsystem = "scsi_host", .file = "unique_id" },
- { .subsystem = "pcmcia_socket", .file = "card_type" },
- { .subsystem = "bluetooth", .file = "address" },
- { .subsystem = "firmware", .file = "data" },
- { .subsystem = "fc_transport", .file = "port_id" },
- { .subsystem = "fc_host", .file = "port_id" },
- { .subsystem = "spi_transport", .file = "width" },
- { .subsystem = "spi_host", .file = "width" },
- { NULL, NULL }
- };
-
- const struct subsystem_file *subsys_file;
- struct sysfs_class_device *class_dev_parent;
- struct sysfs_device *devices_dev = NULL;
- char filename[PATH_SIZE];
- int loop;
-
- /* look if we want to wait for a file */
- for (subsys_file = subsystem_files; subsys_file->subsystem != NULL; subsys_file++)
- if (strcmp(class_dev->classname, subsys_file->subsystem) == 0)
- break;
-
- if (subsys_file->file == NULL) {
- dbg("class '%s' has no file to wait for", class_dev->classname);
- return 0;
+ char path[PATH_SIZE];
+ char devpath_real[PATH_SIZE];
+ struct sysfs_device *dev;
+ struct sysfs_device *dev_loop;
+ struct stat statbuf;
+ char link_path[PATH_SIZE];
+ char link_target[PATH_SIZE];
+ int len;
+ char *pos;
+
+ dbg("open '%s'", devpath);
+ strlcpy(devpath_real, devpath, sizeof(devpath_real));
+ remove_trailing_chars(devpath_real, '/');
+
+ /* look for device already in cache (we never put an untranslated path in the cache) */
+ list_for_each_entry(dev_loop, &dev_list, node) {
+ if (strcmp(dev_loop->devpath, devpath_real) == 0) {
+ dbg("found in cache '%s'", dev_loop->devpath);
+ return dev_loop;
+ }
}
- snprintf(filename, sizeof(filename), "%s/%s", class_dev->path, subsys_file->file);
- filename[sizeof(filename)-1] = '\0';
- dbg("looking at class '%s' for specific file '%s'", class_dev->classname, filename);
-
- loop = WAIT_MAX_SECONDS * WAIT_LOOP_PER_SECOND;
- while (--loop) {
- struct stat stats;
-
- if (stat(class_dev->path, &stats) == -1) {
- dbg("'%s' now disappeared (probably remove has beaten us)", class_dev->path);
- return -ENODEV;
+ /* if we got a link, resolve it to the real device */
+ strlcpy(path, sysfs_path, sizeof(path));
+ strlcat(path, devpath_real, sizeof(path));
+ if (lstat(path, &statbuf) != 0) {
+ dbg("stat '%s' failed: %s", path, strerror(errno));
+ return NULL;
+ }
+ if (S_ISLNK(statbuf.st_mode)) {
+ if (sysfs_resolve_link(devpath_real, sizeof(devpath_real)) != 0)
+ return NULL;
+
+ /* now look for device in cache after path translation */
+ list_for_each_entry(dev_loop, &dev_list, node) {
+ if (strcmp(dev_loop->devpath, devpath_real) == 0) {
+ dbg("found in cache '%s'", dev_loop->devpath);
+ return dev_loop;
+ }
}
+ }
- if (stat(filename, &stats) == 0) {
- dbg("class '%s' specific file '%s' found", class_dev->classname, subsys_file->file);
- return 0;
+ /* it is a new device */
+ dbg("new uncached device '%s'", devpath_real);
+ dev = malloc(sizeof(struct sysfs_device));
+ if (dev == NULL)
+ return NULL;
+ memset(dev, 0x00, sizeof(struct sysfs_device));
+
+ sysfs_device_set_values(dev, devpath_real, NULL, NULL);
+
+ /* get subsystem */
+ if (strncmp(dev->devpath, "/class/", 7) == 0) {
+ strlcpy(dev->subsystem, &dev->devpath[7], sizeof(dev->subsystem));
+ pos = strchr(dev->subsystem, '/');
+ if (pos != NULL)
+ pos[0] = '\0';
+ else
+ dev->subsystem[0] = '\0';
+ } else if (strncmp(dev->devpath, "/block/", 7) == 0) {
+ strlcpy(dev->subsystem, "block", sizeof(dev->subsystem));
+ } else if (strncmp(dev->devpath, "/devices/", 9) == 0) {
+ /* get subsystem from "bus" link */
+ strlcpy(link_path, sysfs_path, sizeof(link_path));
+ strlcat(link_path, dev->devpath, sizeof(link_path));
+ strlcat(link_path, "/bus", sizeof(link_path));
+ len = readlink(link_path, link_target, sizeof(link_target));
+ if (len > 0) {
+ link_target[len] = '\0';
+ dbg("bus link '%s' points to '%s'", link_path, link_target);
+ pos = strrchr(link_target, '/');
+ if (pos != NULL)
+ strlcpy(dev->subsystem, &pos[1], sizeof(dev->subsystem));
+ } else {
+ /* get subsystem from "subsystem" link */
+ strlcpy(link_path, sysfs_path, sizeof(link_path));
+ strlcat(link_path, dev->devpath, sizeof(link_path));
+ strlcat(link_path, "/subsystem", sizeof(link_path));
+ len = readlink(link_path, link_target, sizeof(link_target));
+ if (len > 0) {
+ link_target[len] = '\0';
+ dbg("subsystem link '%s' points to '%s'", link_path, link_target);
+ pos = strrchr(link_target, '/');
+ if (pos != NULL)
+ strlcpy(dev->subsystem, &pos[1], sizeof(dev->subsystem));
+ }
}
-
- usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND);
+ /* get driver name */
+ strlcpy(link_path, sysfs_path, sizeof(link_path));
+ strlcat(link_path, dev->devpath, sizeof(link_path));
+ strlcat(link_path, "/driver", sizeof(link_path));
+ len = readlink(link_path, link_target, sizeof(link_target));
+ if (len > 0) {
+ link_target[len] = '\0';
+ dbg("driver link '%s' points to '%s'", link_path, link_target);
+ pos = strrchr(link_target, '/');
+ if (pos != NULL)
+ strlcpy(dev->driver, &pos[1], sizeof(dev->driver));
+ }
+ } else if (strncmp(dev->devpath, "/bus/", 5) == 0 && strstr(dev->devpath, "/drivers/")) {
+ strlcpy(dev->subsystem, "drivers", sizeof(dev->subsystem));
+ } else if (strncmp(dev->devpath, "/module/", 8) == 0) {
+ strlcpy(dev->subsystem, "module", sizeof(dev->subsystem));
}
- dbg("error: getting class '%s' specific file '%s'", class_dev->classname, subsys_file->file);
- if (error)
- *error = "class specific file unavailable";
- return -1;
-
- /* skip devices without devices-link */
- if (getenv("PHYSDEVPATH") == NULL) {
- dbg("the kernel says, that there is no physical device for '%s'", class_dev->path);
- return 1;
- }
+ dbg("add to cache 'devpath=%s', subsystem='%s', driver='%s'", dev->devpath, dev->subsystem, dev->driver);
+ list_add(&dev->node, &dev_list);
- /* the symlink may be on the parent device */
- class_dev_parent = sysfs_get_classdev_parent(class_dev);
- if (class_dev_parent)
- dbg("looking at parent device for device link '%s'", class_dev_parent->path);
-
- /* wait for the symlink to the devices device */
- dbg("waiting for symlink to devices device");
- loop = WAIT_MAX_SECONDS * WAIT_LOOP_PER_SECOND;
- while (--loop) {
- if (class_dev_parent)
- devices_dev = sysfs_get_classdev_device(class_dev_parent);
- else
- devices_dev = sysfs_get_classdev_device(class_dev);
+ return dev;
+}
- if (devices_dev)
- break;
+struct sysfs_device *sysfs_device_get_parent(struct sysfs_device *dev)
+{
+ char parent_devpath[PATH_SIZE];
+ char *pos;
+
+ dbg("open '%s'", dev->devpath);
+
+ /* look if we already know the parent */
+ if (dev->parent != NULL)
+ return dev->parent;
+
+ /* requesting a parent is only valid for devices */
+ if ((strncmp(dev->devpath, "/devices/", 9) != 0) &&
+ (strncmp(dev->devpath, "/class/", 7) != 0) &&
+ (strncmp(dev->devpath, "/block/", 7) != 0))
+ return NULL;
+
+ strlcpy(parent_devpath, dev->devpath, sizeof(parent_devpath));
+ dbg("'%s'", parent_devpath);
+
+ /* strip last element */
+ pos = strrchr(parent_devpath, '/');
+ if (pos == NULL || pos == parent_devpath)
+ return NULL;
+ pos[0] = '\0';
+
+ /* are we at the top level of /devices */
+ if (strcmp(parent_devpath, "/devices") == 0) {
+ dbg("/devices top level");
+ return NULL;
+ }
- usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND);
+ /* at the top level of class/block we want to follow the "device" link */
+ if (strcmp(parent_devpath, "/block") == 0) {
+ dbg("/block top level, look for device link");
+ goto device_link;
}
- if (!devices_dev) {
- dbg(" error: no devices device symlink found");
- if (error)
- *error = "no device symlink";
- return -ENODEV;
+ if (strncmp(parent_devpath, "/class", 6) == 0) {
+ pos = strrchr(parent_devpath, '/');
+ if (pos == &parent_devpath[6] || pos == parent_devpath) {
+ dbg("/class top level, look for device link");
+ goto device_link;
+ }
}
- dbg("device symlink found pointing to '%s'", devices_dev->path);
+ /* get parent and remember it */
+ dev->parent = sysfs_device_get(parent_devpath);
+ return dev->parent;
+
+device_link:
+ strlcpy(parent_devpath, dev->devpath, sizeof(parent_devpath));
+ strlcat(parent_devpath, "/device", sizeof(parent_devpath));
+ if (sysfs_resolve_link(parent_devpath, sizeof(parent_devpath)) != 0)
+ return NULL;
+
+ /* get parent and remember it */
+ dev->parent = sysfs_device_get(parent_devpath);
+ return dev->parent;
+}
- return wait_for_devices_device(devices_dev, error);
+struct sysfs_device *sysfs_device_get_parent_with_subsystem(struct sysfs_device *dev, const char *subsystem)
+{
+ struct sysfs_device *dev_parent;
+
+ dev_parent = sysfs_device_get_parent(dev);
+ while (dev_parent != NULL) {
+ if (strcmp(dev_parent->subsystem, subsystem) == 0)
+ return dev_parent;
+ dev_parent = sysfs_device_get_parent(dev_parent);
+ }
+ return NULL;
}
-struct sysfs_device *wait_devices_device_open(const char *path)
+char *sysfs_attr_get_value(const char *devpath, const char *attr_name)
{
- struct sysfs_device *devices_dev = NULL;
- int loop;
+ char path_full[PATH_SIZE];
+ const char *path;
+ char value[NAME_SIZE];
+ struct sysfs_attr *attr_loop;
+ struct sysfs_attr *attr;
+ struct stat statbuf;
+ int fd;
+ ssize_t size;
+ size_t sysfs_len;
+
+ dbg("open '%s'/'%s'", devpath, attr_name);
+ sysfs_len = strlcpy(path_full, sysfs_path, sizeof(path_full));
+ path = &path_full[sysfs_len];
+ strlcat(path_full, devpath, sizeof(path_full));
+ strlcat(path_full, "/", sizeof(path_full));
+ strlcat(path_full, attr_name, sizeof(path_full));
+
+ /* look for attribute in cache */
+ list_for_each_entry(attr_loop, &attr_list, node) {
+ if (strcmp(attr_loop->path, path) == 0) {
+ dbg("found in cache '%s'", attr_loop->path);
+ return attr_loop->value;
+ }
+ }
- loop = WAIT_MAX_SECONDS * WAIT_LOOP_PER_SECOND;
- while (--loop) {
- devices_dev = sysfs_open_device_path(path);
- if (devices_dev)
- break;
+ /* store attribute in cache (also negatives are kept in cache) */
+ dbg("new uncached attribute '%s'", path_full);
+ attr = malloc(sizeof(struct sysfs_attr));
+ if (attr == NULL)
+ return NULL;
+ memset(attr, 0x00, sizeof(struct sysfs_attr));
+ strlcpy(attr->path, path, sizeof(attr->path));
+ dbg("add to cache '%s'", path_full);
+ list_add(&attr->node, &attr_list);
+
+ if (lstat(path_full, &statbuf) != 0) {
+ dbg("stat '%s' failed: %s", path_full, strerror(errno));
+ goto out;
+ }
- usleep(1000 * 1000 / WAIT_LOOP_PER_SECOND);
+ if (S_ISLNK(statbuf.st_mode)) {
+ /* links return the last element of the target path */
+ char link_target[PATH_SIZE];
+ int len;
+ const char *pos;
+
+ len = readlink(path_full, link_target, sizeof(link_target));
+ if (len > 0) {
+ link_target[len] = '\0';
+ pos = strrchr(link_target, '/');
+ if (pos != NULL) {
+ dbg("cache '%s' with link value '%s'", path_full, value);
+ strlcpy(attr->value_local, &pos[1], sizeof(attr->value_local));
+ attr->value = attr->value_local;
+ }
+ }
+ goto out;
}
- return devices_dev;
+ /* skip directories */
+ if (S_ISDIR(statbuf.st_mode))
+ goto out;
+
+ /* skip non-readable files */
+ if ((statbuf.st_mode & S_IRUSR) == 0)
+ goto out;
+
+ /* read attribute value */
+ fd = open(path_full, O_RDONLY);
+ if (fd < 0) {
+ dbg("attribute '%s' does not exist", path_full);
+ goto out;
+ }
+ size = read(fd, value, sizeof(value));
+ close(fd);
+ if (size < 0)
+ goto out;
+ if (size == sizeof(value))
+ goto out;
+
+ /* got a valid value, store and return it */
+ value[size] = '\0';
+ remove_trailing_chars(value, '\n');
+ dbg("cache '%s' with attribute value '%s'", path_full, value);
+ strlcpy(attr->value_local, value, sizeof(attr->value_local));
+ attr->value = attr->value_local;
+
+out:
+ return attr->value;
}
~ianmdlvl / elogind.git / blobdiff