/*
- * udev_sysfs.c - sysfs access
- *
- * Copyright (C) 2005 Kay Sievers <kay.sievers@vrfy.org>
+ * 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 <fcntl.h>
#include <ctype.h>
#include <errno.h>
+#include <sys/stat.h>
#include "udev.h"
struct sysfs_attr {
struct list_head node;
char path[PATH_SIZE];
- char value[NAME_SIZE];
+ char *value; /* points to value_local if value is cached */
+ char value_local[NAME_SIZE];
};
int sysfs_init(void)
remove_trailing_chars(sysfs_path, '/');
} else
strlcpy(sysfs_path, "/sys", sizeof(sysfs_path));
- dbg("sysfs_path='%s'", sysfs_path);
+ dbg("sysfs_path='%s'\n", sysfs_path);
INIT_LIST_HEAD(&dev_list);
INIT_LIST_HEAD(&attr_list);
}
}
-void sysfs_device_set_values(struct sysfs_device *dev, const char *devpath, const char *subsystem)
+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_name, &pos[1], sizeof(dev->kernel_name));
- dbg("kernel_name='%s'", dev->kernel_name);
+ strlcpy(dev->kernel, &pos[1], sizeof(dev->kernel));
+ dbg("kernel='%s'\n", dev->kernel);
/* some devices have '!' in their name, change that to '/' */
- pos = dev->kernel_name;
+ pos = dev->kernel;
while (pos[0] != '\0') {
if (pos[0] == '!')
pos[0] = '/';
}
/* get kernel number */
- pos = &dev->kernel_name[strlen(dev->kernel_name)];
+ 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);
+ dbg("kernel_number='%s'\n", dev->kernel_number);
+}
+
+int sysfs_resolve_link(char *devpath, size_t size)
+{
+ 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'\n", devpath, link_target);
+
+ for (back = 0; strncmp(&link_target[back * 3], "../", 3) == 0; back++)
+ ;
+ dbg("base '%s', tail '%s', back %i\n", devpath, &link_target[back * 3], back);
+ for (i = 0; i <= back; i++) {
+ char *pos = strrchr(devpath, '/');
+
+ if (pos == NULL)
+ return -1;
+ pos[0] = '\0';
+ }
+ dbg("after moving back '%s'\n", devpath);
+ strlcat(devpath, "/", size);
+ strlcat(devpath, &link_target[back * 3], size);
+ return 0;
}
struct sysfs_device *sysfs_device_get(const char *devpath)
int len;
char *pos;
- dbg("open '%s'", devpath);
+ /* we handle only these devpathes */
+ if (devpath != NULL &&
+ strncmp(devpath, "/devices/", 9) != 0 &&
+ strncmp(devpath, "/subsystem/", 11) != 0 &&
+ strncmp(devpath, "/module/", 8) != 0 &&
+ strncmp(devpath, "/bus/", 5) != 0 &&
+ strncmp(devpath, "/class/", 7) != 0 &&
+ strncmp(devpath, "/block/", 7) != 0)
+ return NULL;
+
+ dbg("open '%s'\n", devpath);
strlcpy(devpath_real, devpath, sizeof(devpath_real));
remove_trailing_chars(devpath_real, '/');
+ if (devpath[0] == '\0' )
+ return NULL;
+
+ /* 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'\n", dev_loop->devpath);
+ return dev_loop;
+ }
+ }
+ /* 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));
+ dbg("stat '%s' failed: %s\n", path, strerror(errno));
return NULL;
}
-
- /* if we got a link, resolve it to the real device */
if (S_ISLNK(statbuf.st_mode)) {
- int i;
- int back;
-
- len = readlink(path, link_target, sizeof(link_target));
- if (len <= 0)
+ if (sysfs_resolve_link(devpath_real, sizeof(devpath_real)) != 0)
return NULL;
- link_target[len] = '\0';
- dbg("devpath link '%s' points to '%s'", path, link_target);
-
- for (back = 0; strncmp(&link_target[back * 3], "../", 3) == 0; back++)
- ;
- dbg("base '%s', tail '%s', back %i", devpath_real, &link_target[back * 3], back);
- for (i = 0; i <= back; i++) {
- pos = strrchr(devpath_real, '/');
- if (pos == NULL)
- return NULL;
- pos[0] = '\0';
- }
- dbg("after moving back '%s'", devpath_real);
- strlcat(devpath_real, "/", sizeof(devpath_real));
- strlcat(devpath_real, &link_target[back * 3], sizeof(devpath_real));
- }
- /* look for device in 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;
+ /* 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'\n", dev_loop->devpath);
+ return dev_loop;
+ }
}
}
- /* new device */
- dbg("'%s'", devpath_real);
+ /* it is a new device */
+ dbg("new uncached device '%s'\n", 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);
+ 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, '/');
+ /* get subsystem name */
+ 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) {
+ /* get subsystem from "subsystem" link */
+ link_target[len] = '\0';
+ dbg("subsystem link '%s' points to '%s'\n", link_path, link_target);
+ pos = strrchr(link_target, '/');
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));
- }
- }
- /* 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, &pos[1], sizeof(dev->subsystem));
+ } else if (strstr(dev->devpath, "/drivers/") != NULL) {
strlcpy(dev->subsystem, "drivers", sizeof(dev->subsystem));
} else if (strncmp(dev->devpath, "/module/", 8) == 0) {
strlcpy(dev->subsystem, "module", sizeof(dev->subsystem));
+ } else if (strncmp(dev->devpath, "/subsystem/", 11) == 0) {
+ pos = strrchr(dev->devpath, '/');
+ if (pos == &dev->devpath[10])
+ strlcpy(dev->subsystem, "subsystem", sizeof(dev->subsystem));
+ } else if (strncmp(dev->devpath, "/class/", 7) == 0) {
+ pos = strrchr(dev->devpath, '/');
+ if (pos == &dev->devpath[6])
+ strlcpy(dev->subsystem, "subsystem", sizeof(dev->subsystem));
+ } else if (strncmp(dev->devpath, "/bus/", 5) == 0) {
+ pos = strrchr(dev->devpath, '/');
+ if (pos == &dev->devpath[4])
+ strlcpy(dev->subsystem, "subsystem", sizeof(dev->subsystem));
}
- dbg("add to cache 'devpath=%s', subsystem='%s', driver='%s'", dev->devpath, dev->subsystem, dev->driver);
+ /* 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'\n", link_path, link_target);
+ pos = strrchr(link_target, '/');
+ if (pos != NULL)
+ strlcpy(dev->driver, &pos[1], sizeof(dev->driver));
+ }
+
+ dbg("add to cache 'devpath=%s', subsystem='%s', driver='%s'\n", dev->devpath, dev->subsystem, dev->driver);
list_add(&dev->node, &dev_list);
return dev;
struct sysfs_device *sysfs_device_get_parent(struct sysfs_device *dev)
{
char parent_devpath[PATH_SIZE];
- char device_link[PATH_SIZE];
- char device_link_target[PATH_SIZE];
char *pos;
- int i;
- int len;
- int back;
- /* 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;
+ dbg("open '%s'\n", dev->devpath);
+
+ /* look if we already know the parent */
+ if (dev->parent != NULL)
+ return dev->parent;
strlcpy(parent_devpath, dev->devpath, sizeof(parent_devpath));
- dbg("'%s'", parent_devpath);
+ dbg("'%s'\n", parent_devpath);
/* strip last element */
pos = strrchr(parent_devpath, '/');
return NULL;
pos[0] = '\0';
- /* are we at the top level */
- if (strcmp(parent_devpath, "/devices") == 0) {
- dbg("/devices top level");
- return NULL;
- }
-
- /* at the top level we may follow the "device" link */
- if (strcmp(parent_devpath, "/block") == 0) {
- dbg("/block top level, look for device link");
- goto device_link;
- }
-
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");
+ dbg("/class top level, look for device link\n");
goto device_link;
}
}
- return sysfs_device_get(parent_devpath);
+ if (strcmp(parent_devpath, "/block") == 0) {
+ dbg("/block top level, look for device link\n");
+ goto device_link;
+ }
-device_link:
- strlcpy(device_link, sysfs_path, sizeof(device_link));
- strlcat(device_link, dev->devpath, sizeof(device_link));
- strlcat(device_link, "/device", sizeof(device_link));
- len = readlink(device_link, device_link_target, sizeof(device_link_target));
- if (len < 0)
+ /* are we at the top level? */
+ pos = strrchr(parent_devpath, '/');
+ if (pos == NULL || pos == parent_devpath)
return NULL;
- device_link_target[len] = '\0';
- dbg("device link '%s' points to '%s'", device_link, device_link_target);
- for (back = 0; strncmp(&device_link_target[back * 3], "../", 3) == 0; back++)
- ;
+ /* 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));
- dbg("base='%s', tail='%s', back=%i", parent_devpath, &device_link_target[back * 3], back);
- for (i = 0; i < back; i++) {
- pos = strrchr(parent_devpath, '/');
- if (pos == NULL)
- return NULL;
- pos[0] = '\0';
- }
- dbg("after moving back '%s'", parent_devpath);
- strlcat(parent_devpath, "/", sizeof(parent_devpath));
- strlcat(parent_devpath, &device_link_target[back * 3], sizeof(parent_devpath));
- return sysfs_device_get(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;
}
struct sysfs_device *sysfs_device_get_parent_with_subsystem(struct sysfs_device *dev, const char *subsystem)
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'\n", devpath, attr_name);
sysfs_len = strlcpy(path_full, sysfs_path, sizeof(path_full));
+ if(sysfs_len >= sizeof(path_full))
+ sysfs_len = sizeof(path_full) - 1;
path = &path_full[sysfs_len];
strlcat(path_full, devpath, sizeof(path_full));
strlcat(path_full, "/", 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);
+ dbg("found in cache '%s'\n", attr_loop->path);
return attr_loop->value;
}
}
+ /* store attribute in cache (also negatives are kept in cache) */
+ dbg("new uncached attribute '%s'\n", 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'\n", path_full);
+ list_add(&attr->node, &attr_list);
+
+ if (lstat(path_full, &statbuf) != 0) {
+ dbg("stat '%s' failed: %s\n", path_full, strerror(errno));
+ goto out;
+ }
+
+ 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'\n", path_full, value);
+ strlcpy(attr->value_local, &pos[1], sizeof(attr->value_local));
+ attr->value = attr->value_local;
+ }
+ }
+ goto out;
+ }
+
+ /* 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)
- return NULL;
+ if (fd < 0) {
+ dbg("attribute '%s' can not be opened\n", path_full);
+ goto out;
+ }
size = read(fd, value, sizeof(value));
close(fd);
if (size < 0)
- return NULL;
+ goto out;
if (size == sizeof(value))
- return NULL;
+ 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'\n", path_full, value);
+ strlcpy(attr->value_local, value, sizeof(attr->value_local));
+ attr->value = attr->value_local;
- /* store attribute in cache */
- attr = malloc(sizeof(struct sysfs_attr));
- if (attr == NULL)
- return NULL;
- strlcpy(attr->path, path, sizeof(attr->path));
- strlcpy(attr->value, value, sizeof(attr->value));
- dbg("add to cache '%s' '%s'", attr->path, attr->value);
- list_add(&attr->node, &attr_list);
-
+out:
return attr->value;
}
+
+int sysfs_lookup_devpath_by_subsys_id(char *devpath_full, size_t len, const char *subsystem, const char *id)
+{
+ size_t sysfs_len;
+ char path_full[PATH_SIZE];
+ char *path;
+ struct stat statbuf;
+
+ sysfs_len = strlcpy(path_full, sysfs_path, sizeof(path_full));
+ path = &path_full[sysfs_len];
+
+ if (strcmp(subsystem, "subsystem") == 0) {
+ strlcpy(path, "/subsystem/", sizeof(path_full) - sysfs_len);
+ strlcat(path, id, sizeof(path_full) - sysfs_len);
+ if (stat(path_full, &statbuf) == 0)
+ goto found;
+
+ strlcpy(path, "/bus/", sizeof(path_full) - sysfs_len);
+ strlcat(path, id, sizeof(path_full) - sysfs_len);
+ if (stat(path_full, &statbuf) == 0)
+ goto found;
+ goto out;
+
+ strlcpy(path, "/class/", sizeof(path_full) - sysfs_len);
+ strlcat(path, id, sizeof(path_full) - sysfs_len);
+ if (stat(path_full, &statbuf) == 0)
+ goto found;
+ }
+
+ if (strcmp(subsystem, "module") == 0) {
+ strlcpy(path, "/module/", sizeof(path_full) - sysfs_len);
+ strlcat(path, id, sizeof(path_full) - sysfs_len);
+ if (stat(path_full, &statbuf) == 0)
+ goto found;
+ goto out;
+ }
+
+ if (strcmp(subsystem, "drivers") == 0) {
+ char subsys[NAME_SIZE];
+ char *driver;
+
+ strlcpy(subsys, id, sizeof(subsys));
+ driver = strchr(subsys, ':');
+ if (driver != NULL) {
+ driver[0] = '\0';
+ driver = &driver[1];
+ strlcpy(path, "/subsystem/", sizeof(path_full) - sysfs_len);
+ strlcat(path, subsys, sizeof(path_full) - sysfs_len);
+ strlcat(path, "/drivers/", sizeof(path_full) - sysfs_len);
+ strlcat(path, driver, sizeof(path_full) - sysfs_len);
+ if (stat(path_full, &statbuf) == 0)
+ goto found;
+
+ strlcpy(path, "/bus/", sizeof(path_full) - sysfs_len);
+ strlcat(path, subsys, sizeof(path_full) - sysfs_len);
+ strlcat(path, "/drivers/", sizeof(path_full) - sysfs_len);
+ strlcat(path, driver, sizeof(path_full) - sysfs_len);
+ if (stat(path_full, &statbuf) == 0)
+ goto found;
+ }
+ goto out;
+ }
+
+ strlcpy(path, "/subsystem/", sizeof(path_full) - sysfs_len);
+ strlcat(path, subsystem, sizeof(path_full) - sysfs_len);
+ strlcat(path, "/devices/", sizeof(path_full) - sysfs_len);
+ strlcat(path, id, sizeof(path_full) - sysfs_len);
+ if (stat(path_full, &statbuf) == 0)
+ goto found;
+
+ strlcpy(path, "/bus/", sizeof(path_full) - sysfs_len);
+ strlcat(path, subsystem, sizeof(path_full) - sysfs_len);
+ strlcat(path, "/devices/", sizeof(path_full) - sysfs_len);
+ strlcat(path, id, sizeof(path_full) - sysfs_len);
+ if (stat(path_full, &statbuf) == 0)
+ goto found;
+
+ strlcpy(path, "/class/", sizeof(path_full) - sysfs_len);
+ strlcat(path, subsystem, sizeof(path_full) - sysfs_len);
+ strlcat(path, "/", sizeof(path_full) - sysfs_len);
+ strlcat(path, id, sizeof(path_full) - sysfs_len);
+ if (stat(path_full, &statbuf) == 0)
+ goto found;
+out:
+ return 0;
+found:
+ if (S_ISLNK(statbuf.st_mode))
+ sysfs_resolve_link(path, sizeof(path_full) - sysfs_len);
+ strlcpy(devpath_full, path, len);
+ return 1;
+}
~ianmdlvl / elogind.git / blobdiff