/*
- * syfs_utils.c
+ * sysfs_utils.c
*
* System utility functions for libsysfs
*
#include <mntent.h>
#endif
+/**
+ * sysfs_remove_trailing_slash: Removes any trailing '/' in the given path
+ * @path: Path to look for the trailing '/'
+ * Returns 0 on success 1 on error
+ */
+int sysfs_remove_trailing_slash(unsigned char *path)
+{
+ unsigned char *c = NULL;
+
+ if (path == NULL) {
+ errno = EINVAL;
+ return 1;
+ }
+ c = strrchr(path, '/');
+ if (c == NULL) {
+ dprintf("Invalid path %s\n", path);
+ errno = EINVAL;
+ return 1;
+ }
+ if (*(c+1) == '\0')
+ *c = '\0';
+ return 0;
+}
+
/**
* sysfs_get_mnt_path: Gets the mount point for specified filesystem.
* @fs_type: filesystem type to retrieve mount point
errno = EINVAL;
ret = -1;
}
+ if ((sysfs_remove_trailing_slash(mnt_path)) != 0)
+ ret = -1;
+
return ret;
#endif
}
*/
int sysfs_get_mnt_path(unsigned char *mnt_path, size_t len)
{
- int ret = -1;
+ char *sysfs_path = NULL;
+ int ret = 0;
- if (mnt_path != NULL)
- ret = sysfs_get_fs_mnt_path(SYSFS_FSTYPE_NAME, mnt_path, len);
- else
+ if (mnt_path == NULL) {
errno = EINVAL;
+ return -1;
+ }
+ sysfs_path = getenv(SYSFS_PATH_ENV);
+ if (sysfs_path != NULL) {
+ strncpy(mnt_path, sysfs_path, len);
+ if ((sysfs_remove_trailing_slash(mnt_path)) != 0)
+ return 1;
+ } else
+ ret = sysfs_get_fs_mnt_path(SYSFS_FSTYPE_NAME, mnt_path, len);
return ret;
}
int sysfs_get_name_from_path(const unsigned char *path, unsigned char *name,
size_t len)
{
+ unsigned char tmp[SYSFS_PATH_MAX];
unsigned char *n = NULL;
if (path == NULL || name == NULL) {
errno = EINVAL;
return -1;
}
- n = strrchr(path, '/');
+ memset(tmp, 0, SYSFS_PATH_MAX);
+ strcpy(tmp, path);
+ n = strrchr(tmp, '/');
if (n == NULL) {
errno = EINVAL;
return -1;
}
+ if (*(n+1) == '\0') {
+ *n = '\0';
+ n = strrchr(tmp, '/');
+ if (n == NULL) {
+ errno = EINVAL;
+ return -1;
+ }
+ }
n++;
strncpy(name, n, len);
-
return 0;
}
-
+
/**
* sysfs_get_link: returns link source
* @path: symbolic link's path
{
unsigned char devdir[SYSFS_PATH_MAX];
unsigned char linkpath[SYSFS_PATH_MAX];
- unsigned char *d = NULL;
+ unsigned char *d = NULL, *s = NULL;
+ int slashes = 0, count = 0;
if (path == NULL || target == NULL) {
errno = EINVAL;
memset(devdir, 0, SYSFS_PATH_MAX);
memset(linkpath, 0, SYSFS_PATH_MAX);
+ strncpy(devdir, path, SYSFS_PATH_MAX);
- if ((sysfs_get_mnt_path(devdir, SYSFS_PATH_MAX)) != 0) {
- dprintf("Sysfs not supported on this system\n");
- return -1;
- }
-
if ((readlink(path, linkpath, SYSFS_PATH_MAX)) < 0) {
return -1;
}
-
d = linkpath;
-
- /* getting rid of leading "../.." */
- while (*d == '/' || *d == '.')
- d++;
-
- d--;
-
- strcat(devdir, d);
- strncpy(target, devdir, len);
-
+ /*
+ * Three cases here:
+ * 1. relative path => format ../..
+ * 2. absolute path => format /abcd/efgh
+ * 3. relative path _from_ this dir => format abcd/efgh
+ */
+ switch (*d) {
+ case '.':
+ /*
+ * handle the case where link is of type ./abcd/xxx
+ */
+ strncpy(target, devdir, len);
+ if (*(d+1) == '/')
+ d += 2;
+ else if (*(d+1) == '.')
+ goto parse_path;
+ s = strrchr(target, '/');
+ if (s != NULL) {
+ *(s+1) = '\0';
+ strcat(target, d);
+ } else {
+ strcpy(target, d);
+ }
+ break;
+ /*
+ * relative path
+ * getting rid of leading "../.."
+ */
+parse_path:
+ while (*d == '/' || *d == '.') {
+ if (*d == '/')
+ slashes++;
+ d++;
+ }
+ d--;
+ s = &devdir[strlen(devdir)-1];
+ while (s != NULL && count != (slashes+1)) {
+ s--;
+ if (*s == '/')
+ count++;
+ }
+ strncpy(s, d, (SYSFS_PATH_MAX-strlen(devdir)));
+ strncpy(target, devdir, len);
+ break;
+ case '/':
+ /* absolute path - copy as is */
+ strncpy(target, linkpath, len);
+ break;
+ default:
+ /* relative path from this directory */
+ strncpy(target, devdir, len);
+ s = strrchr(target, '/');
+ if (s != NULL) {
+ *(s+1) = '\0';
+ strcat(target, linkpath);
+ } else {
+ strcpy(target, linkpath);
+ }
+ }
return 0;
}
-
/**
* sysfs_del_name: free function for sysfs_open_subsystem_list
* @name: memory area to be freed
*/
-void sysfs_del_name(void *name)
+static void sysfs_del_name(void *name)
{
free(name);
}
struct dlist *sysfs_open_subsystem_list(unsigned char *name)
{
unsigned char sysfs_path[SYSFS_PATH_MAX], *subsys_name = NULL;
+ unsigned char *c = NULL;
struct sysfs_directory *dir = NULL, *cur = NULL;
struct dlist *list = NULL;
return NULL;
}
+ strcat(sysfs_path, "/");
strcat(sysfs_path, name);
dir = sysfs_open_directory(sysfs_path);
if (dir == NULL) {
return NULL;
}
- if (sysfs_read_directory(dir) != 0) {
+ if ((sysfs_read_dir_subdirs(dir)) != 0) {
dprintf("Error reading sysfs_directory at %s\n", sysfs_path);
sysfs_close_directory(dir);
return NULL;
}
}
sysfs_close_directory(dir);
+ /*
+ * We are now considering "block" as a "class". Hence, if the subsys
+ * name requested here is "class", verify if "block" is supported on
+ * this system and return the same.
+ */
+ if (strcmp(name, SYSFS_CLASS_NAME) == 0) {
+ c = strstr(sysfs_path, SYSFS_CLASS_NAME);
+ if (c == NULL)
+ goto out;
+ strcpy(c, SYSFS_BLOCK_NAME);
+ if ((sysfs_path_is_dir(sysfs_path)) == 0) {
+ subsys_name = (char *)calloc(1, SYSFS_NAME_LEN);
+ strcpy(subsys_name, SYSFS_BLOCK_NAME);
+ dlist_unshift(list, subsys_name);
+ }
+ }
+out:
return list;
}
return NULL;
}
- strcat(sysfs_path, SYSFS_BUS_DIR);
+ strcat(sysfs_path, "/");
+ strcat(sysfs_path, SYSFS_BUS_NAME);
strcat(sysfs_path, "/");
strcat(sysfs_path, name);
- strcat(sysfs_path, SYSFS_DEVICES_DIR);
+ strcat(sysfs_path, "/");
+ strcat(sysfs_path, SYSFS_DEVICES_NAME);
dir = sysfs_open_directory(sysfs_path);
if (dir == NULL) {
dprintf("Error opening sysfs_directory at %s\n", sysfs_path);
return NULL;
}
- if (sysfs_read_directory(dir) != 0) {
+ if ((sysfs_read_dir_links(dir)) != 0) {
dprintf("Error reading sysfs_directory at %s\n", sysfs_path);
sysfs_close_directory(dir);
return NULL;
return list;
}
+/**
+ * sysfs_path_is_dir: Check if the path supplied points to a directory
+ * @path: path to validate
+ * Returns 0 if path points to dir, 1 otherwise
+ */
+int sysfs_path_is_dir(const unsigned char *path)
+{
+ struct stat astats;
+
+ if (path == NULL) {
+ errno = EINVAL;
+ return 1;
+ }
+ if ((lstat(path, &astats)) != 0) {
+ dprintf("stat() failed\n");
+ return 1;
+ }
+ if (S_ISDIR(astats.st_mode))
+ return 0;
+
+ return 1;
+}
+
+/**
+ * sysfs_path_is_link: Check if the path supplied points to a link
+ * @path: path to validate
+ * Returns 0 if path points to link, 1 otherwise
+ */
+int sysfs_path_is_link(const unsigned char *path)
+{
+ struct stat astats;
+
+ if (path == NULL) {
+ errno = EINVAL;
+ return 1;
+ }
+ if ((lstat(path, &astats)) != 0) {
+ dprintf("stat() failed\n");
+ return 1;
+ }
+ if (S_ISLNK(astats.st_mode))
+ return 0;
+
+ return 1;
+}
+
+/**
+ * sysfs_path_is_file: Check if the path supplied points to a file
+ * @path: path to validate
+ * Returns 0 if path points to file, 1 otherwise
+ */
+int sysfs_path_is_file(const unsigned char *path)
+{
+ struct stat astats;
+
+ if (path == NULL) {
+ errno = EINVAL;
+ return 1;
+ }
+ if ((lstat(path, &astats)) != 0) {
+ dprintf("stat() failed\n");
+ return 1;
+ }
+ if (S_ISREG(astats.st_mode))
+ return 0;
+
+ return 1;
+}