4 * Directory utility functions for libsysfs
6 * Copyright (C) IBM Corp. 2003
8 * This library is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU Lesser General Public
10 * License as published by the Free Software Foundation; either
11 * version 2.1 of the License, or (at your option) any later version.
13 * This library is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16 * Lesser General Public License for more details.
18 * You should have received a copy of the GNU Lesser General Public
19 * License along with this library; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
27 * sysfs_del_attribute: routine for dlist integration
29 static void sysfs_del_attribute(void *attr
)
31 sysfs_close_attribute((struct sysfs_attribute
*)attr
);
35 * sysfs_del_link: routine for dlist integration
37 static void sysfs_del_link(void *ln
)
39 sysfs_close_link((struct sysfs_link
*)ln
);
43 * sysfs_del_dir: routine for dlist integration
45 static void sysfs_del_directory(void *dir
)
47 sysfs_close_directory((struct sysfs_directory
*)dir
);
51 * dir_attribute_name_equal: compares dir attributes by name
52 * @a: attribute name for comparison
53 * @b: sysfs_attribute to be compared.
54 * returns 1 if a==b->name or 0 if not equal
56 static int dir_attribute_name_equal(void *a
, void *b
)
58 if (a
== NULL
|| b
== NULL
)
61 if (strcmp(((unsigned char *)a
), ((struct sysfs_attribute
*)b
)->name
)
68 * dir_link_name_equal: compares dir links by name
69 * @a: link name for comparison
70 * @b: sysfs_link to be compared.
71 * returns 1 if a==b->name or 0 if not equal
73 static int dir_link_name_equal(void *a
, void *b
)
75 if (a
== NULL
|| b
== NULL
)
78 if (strcmp(((unsigned char *)a
), ((struct sysfs_link
*)b
)->name
)
85 * dir_subdir_name_equal: compares subdirs by name
86 * @a: name of subdirectory to compare
87 * @b: sysfs_directory subdirectory to be compared
88 * returns 1 if a==b->name or 0 if not equal
90 static int dir_subdir_name_equal(void *a
, void *b
)
92 if (a
== NULL
|| b
== NULL
)
95 if (strcmp(((unsigned char *)a
), ((struct sysfs_directory
*)b
)->name
)
102 * sysfs_close_attribute: closes and cleans up attribute
103 * @sysattr: attribute to close.
105 void sysfs_close_attribute(struct sysfs_attribute
*sysattr
)
107 if (sysattr
!= NULL
) {
108 if (sysattr
->value
!= NULL
)
109 free(sysattr
->value
);
115 * alloc_attribute: allocates and initializes attribute structure
116 * returns struct sysfs_attribute with success and NULL with error.
118 static struct sysfs_attribute
*alloc_attribute(void)
120 return (struct sysfs_attribute
*)
121 calloc(1, sizeof(struct sysfs_attribute
));
125 * sysfs_open_attribute: creates sysfs_attribute structure
126 * @path: path to attribute.
127 * returns sysfs_attribute struct with success and NULL with error.
129 struct sysfs_attribute
*sysfs_open_attribute(const unsigned char *path
)
131 struct sysfs_attribute
*sysattr
= NULL
;
132 struct stat fileinfo
;
138 sysattr
= alloc_attribute();
139 if (sysattr
== NULL
) {
140 dprintf("Error allocating attribute at %s\n", path
);
143 if (sysfs_get_name_from_path(path
, sysattr
->name
, SYSFS_NAME_LEN
)
145 dprintf("Error retrieving attribute name from path: %s\n",
147 sysfs_close_attribute(sysattr
);
150 strncpy(sysattr
->path
, path
, SYSFS_PATH_MAX
);
151 if ((stat(sysattr
->path
, &fileinfo
)) != 0) {
152 dprintf("Stat failed: No such attribute?\n");
157 if (fileinfo
.st_mode
& S_IRUSR
)
158 sysattr
->method
|= SYSFS_METHOD_SHOW
;
159 if (fileinfo
.st_mode
& S_IWUSR
)
160 sysattr
->method
|= SYSFS_METHOD_STORE
;
167 * sysfs_write_attribute: write value to the attribute
168 * @sysattr: attribute to write
169 * @new_value: value to write
170 * @len: length of "new_value"
171 * returns 0 with success and -1 with error.
173 int sysfs_write_attribute(struct sysfs_attribute
*sysattr
,
174 const unsigned char *new_value
, size_t len
)
179 if (sysattr
== NULL
|| new_value
== NULL
|| len
== 0) {
184 if (!(sysattr
->method
& SYSFS_METHOD_STORE
)) {
185 dprintf ("Store method not supported for attribute %s\n",
189 if (sysattr
->method
& SYSFS_METHOD_SHOW
) {
191 * read attribute again to see if we can get an updated value
193 if ((sysfs_read_attribute(sysattr
)) != 0) {
194 dprintf("Error reading attribute\n");
197 if ((strncmp(sysattr
->value
, new_value
, sysattr
->len
)) == 0) {
198 dprintf("Attr %s already has the requested value %s\n",
199 sysattr
->name
, new_value
);
204 * open O_WRONLY since some attributes have no "read" but only
207 if ((fd
= open(sysattr
->path
, O_WRONLY
)) < 0) {
208 dprintf("Error reading attribute %s\n", sysattr
->path
);
212 length
= write(fd
, new_value
, len
);
214 dprintf("Error writing to the attribute %s - invalid value?\n",
218 } else if (length
!= len
) {
219 dprintf("Could not write %d bytes to attribute %s\n",
222 * since we could not write user supplied number of bytes,
223 * restore the old value if one available
225 if (sysattr
->method
& SYSFS_METHOD_SHOW
) {
226 length
= write(fd
, sysattr
->value
, sysattr
->len
);
233 * Validate length that has been copied. Alloc appropriate area
234 * in sysfs_attribute. Verify first if the attribute supports reading
235 * (show method). If it does not, do not bother
237 if (sysattr
->method
& SYSFS_METHOD_SHOW
) {
238 if (length
!= sysattr
->len
) {
239 sysattr
->value
= (char *)realloc(sysattr
->value
,
241 sysattr
->len
= length
;
242 strncpy(sysattr
->value
, new_value
, length
);
244 /*"length" of the new value is same as old one */
245 strncpy(sysattr
->value
, new_value
, length
);
255 * sysfs_read_attribute: reads value from attribute
256 * @sysattr: attribute to read
257 * returns 0 with success and -1 with error.
259 int sysfs_read_attribute(struct sysfs_attribute
*sysattr
)
261 unsigned char *fbuf
= NULL
;
262 unsigned char *vbuf
= NULL
;
267 if (sysattr
== NULL
) {
271 if (!(sysattr
->method
& SYSFS_METHOD_SHOW
)) {
272 dprintf("Show method not supported for attribute %s\n",
279 pgsize
= sysconf(_SC_PAGESIZE
);
281 fbuf
= (unsigned char *)calloc(1, pgsize
+1);
283 dprintf("calloc failed\n");
286 if ((fd
= open(sysattr
->path
, O_RDONLY
)) < 0) {
287 dprintf("Error reading attribute %s\n", sysattr
->path
);
291 length
= read(fd
, fbuf
, pgsize
);
293 dprintf("Error reading from attribute %s\n", sysattr
->path
);
298 if (sysattr
->len
> 0) {
299 if ((sysattr
->len
== length
) &&
300 (!(strncmp(sysattr
->value
, fbuf
, length
)))) {
304 free(sysattr
->value
);
306 sysattr
->len
= length
;
308 vbuf
= (unsigned char *)realloc(fbuf
, length
+1);
310 dprintf("realloc failed\n");
314 sysattr
->value
= vbuf
;
320 * sysfs_read_attribute_value: given path to attribute, return its value.
321 * values can be up to a pagesize, if buffer is smaller the value will
323 * @attrpath: sysfs path to attribute
324 * @value: buffer to put value
325 * @vsize: size of value buffer
326 * returns 0 with success and -1 with error.
328 int sysfs_read_attribute_value(const unsigned char *attrpath
,
329 unsigned char *value
, size_t vsize
)
331 struct sysfs_attribute
*attr
= NULL
;
334 if (attrpath
== NULL
|| value
== NULL
) {
339 attr
= sysfs_open_attribute(attrpath
);
341 dprintf("Invalid attribute path %s\n", attrpath
);
345 if((sysfs_read_attribute(attr
)) != 0 || attr
->value
== NULL
) {
346 dprintf("Error reading from attribute %s\n", attrpath
);
347 sysfs_close_attribute(attr
);
350 length
= strlen(attr
->value
);
352 dprintf("Value length %d is larger than supplied buffer %d\n",
354 strncpy(value
, attr
->value
, vsize
);
355 sysfs_close_attribute(attr
);
361 * sysfs_get_value_from_attrbutes: given a linked list of attributes and an
362 * attribute name, return its value
363 * @attr: attribute to search
364 * @name: name to look for
365 * returns unsigned char * value - could be NULL
367 unsigned char *sysfs_get_value_from_attributes(struct dlist
*attr
,
368 const unsigned char *name
)
370 struct sysfs_attribute
*cur
= NULL
;
372 if (attr
== NULL
|| name
== NULL
) {
376 dlist_for_each_data(attr
, cur
, struct sysfs_attribute
) {
377 if (strcmp(cur
->name
, name
) == 0)
384 * sysfs_close_link: closes and cleans up link.
385 * @ln: link to close.
387 void sysfs_close_link(struct sysfs_link
*ln
)
394 * sysfs_close_directory: closes directory, cleans up attributes and links
395 * @sysdir: sysfs_directory to close
397 void sysfs_close_directory(struct sysfs_directory
*sysdir
)
399 if (sysdir
!= NULL
) {
400 if (sysdir
->subdirs
!= NULL
)
401 dlist_destroy(sysdir
->subdirs
);
402 if (sysdir
->links
!= NULL
)
403 dlist_destroy(sysdir
->links
);
404 if (sysdir
->attributes
!= NULL
)
405 dlist_destroy(sysdir
->attributes
);
412 * alloc_directory: allocates and initializes directory structure
413 * returns struct sysfs_directory with success or NULL with error.
415 static struct sysfs_directory
*alloc_directory(void)
417 return (struct sysfs_directory
*)
418 calloc(1, sizeof(struct sysfs_directory
));
422 * alloc_link: allocates and initializes link structure
423 * returns struct sysfs_link with success or NULL with error.
425 static struct sysfs_link
*alloc_link(void)
427 return (struct sysfs_link
*)calloc(1, sizeof(struct sysfs_link
));
431 * sysfs_read_all_subdirs: calls sysfs_read_directory for all subdirs
432 * @sysdir: directory whose subdirs need reading.
433 * returns 0 with success and -1 with error.
435 int sysfs_read_all_subdirs(struct sysfs_directory
*sysdir
)
437 struct sysfs_directory
*cursub
= NULL
;
439 if (sysdir
== NULL
) {
443 if (sysdir
->subdirs
== NULL
)
444 if ((sysfs_read_dir_subdirs(sysdir
)) != 0)
446 if (sysdir
->subdirs
!= NULL
) {
447 dlist_for_each_data(sysdir
->subdirs
, cursub
,
448 struct sysfs_directory
) {
449 if ((sysfs_read_dir_subdirs(cursub
)) != 0)
450 dprintf ("Error reading subdirectory %s\n",
458 * sysfs_open_directory: opens a sysfs directory, creates dir struct, and
460 * @path: path of directory to open.
461 * returns: struct sysfs_directory * with success and NULL on error.
463 struct sysfs_directory
*sysfs_open_directory(const unsigned char *path
)
465 struct sysfs_directory
*sdir
= NULL
;
472 if (sysfs_path_is_dir(path
) != 0) {
473 dprintf("Invalid path directory %s\n", path
);
478 sdir
= alloc_directory();
480 dprintf("Error allocating directory %s\n", path
);
483 if (sysfs_get_name_from_path(path
, sdir
->name
, SYSFS_NAME_LEN
) != 0) {
484 dprintf("Error getting directory name from path: %s\n", path
);
485 sysfs_close_directory(sdir
);
488 strncpy(sdir
->path
, path
, SYSFS_PATH_MAX
);
494 * sysfs_open_link: opens a sysfs link, creates struct, and returns
495 * @path: path of link to open.
496 * returns: struct sysfs_link * with success and NULL on error.
498 struct sysfs_link
*sysfs_open_link(const unsigned char *linkpath
)
500 struct sysfs_link
*ln
= NULL
;
502 if (linkpath
== NULL
|| strlen(linkpath
) > SYSFS_PATH_MAX
) {
509 dprintf("Error allocating link %s\n", linkpath
);
512 strcpy(ln
->path
, linkpath
);
513 if ((sysfs_get_name_from_path(linkpath
, ln
->name
, SYSFS_NAME_LEN
)) != 0
514 || (sysfs_get_link(linkpath
, ln
->target
, SYSFS_PATH_MAX
)) != 0) {
516 dprintf("Invalid link path %s\n", linkpath
);
524 * add_attribute: open and add attribute at path to given directory
525 * @sysdir: directory to add attribute to
526 * @path: path to attribute
527 * returns 0 with success and -1 with error.
529 static int add_attribute(struct sysfs_directory
*sysdir
,
530 const unsigned char *path
)
532 struct sysfs_attribute
*attr
= NULL
;
534 attr
= sysfs_open_attribute(path
);
536 dprintf("Error opening attribute %s\n", path
);
539 if (attr
->method
& SYSFS_METHOD_SHOW
) {
540 if ((sysfs_read_attribute(attr
)) != 0) {
541 dprintf("Error reading attribute %s\n", path
);
542 sysfs_close_attribute(attr
);
547 if (sysdir
->attributes
== NULL
) {
548 sysdir
->attributes
= dlist_new_with_delete
549 (sizeof(struct sysfs_attribute
), sysfs_del_attribute
);
551 dlist_unshift(sysdir
->attributes
, attr
);
557 * add_subdirectory: open and add subdirectory at path to given directory
558 * @sysdir: directory to add subdir to
559 * @path: path to subdirectory
560 * returns 0 with success and -1 with error.
562 static int add_subdirectory(struct sysfs_directory
*sysdir
,
563 const unsigned char *path
)
565 struct sysfs_directory
*subdir
= NULL
;
567 subdir
= sysfs_open_directory(path
);
568 if (subdir
== NULL
) {
569 dprintf("Error opening directory %s\n", path
);
572 if (sysdir
->subdirs
== NULL
)
573 sysdir
->subdirs
= dlist_new_with_delete
574 (sizeof(struct sysfs_directory
), sysfs_del_directory
);
575 dlist_unshift(sysdir
->subdirs
, subdir
);
580 * add_link: open and add link at path to given directory
581 * @sysdir: directory to add link to
582 * @path: path to link
583 * returns 0 with success and -1 with error.
585 static int add_link(struct sysfs_directory
*sysdir
, const unsigned char *path
)
587 struct sysfs_link
*ln
= NULL
;
589 ln
= sysfs_open_link(path
);
591 dprintf("Error opening link %s\n", path
);
594 if (sysdir
->links
== NULL
)
595 sysdir
->links
= dlist_new_with_delete
596 (sizeof(struct sysfs_link
), sysfs_del_link
);
597 dlist_unshift(sysdir
->links
, ln
);
602 * sysfs_read_dir_attributes: grabs attributes for the given directory
603 * @sysdir: sysfs directory to open
604 * returns 0 with success and -1 with error.
606 int sysfs_read_dir_attributes(struct sysfs_directory
*sysdir
)
609 struct dirent
*dirent
= NULL
;
610 unsigned char file_path
[SYSFS_PATH_MAX
];
613 if (sysdir
== NULL
) {
617 dir
= opendir(sysdir
->path
);
619 dprintf("Error opening directory %s\n", sysdir
->path
);
622 while(((dirent
= readdir(dir
)) != NULL
) && retval
== 0) {
623 if (0 == strcmp(dirent
->d_name
, "."))
625 if (0 == strcmp(dirent
->d_name
, ".."))
627 memset(file_path
, 0, SYSFS_PATH_MAX
);
628 strncpy(file_path
, sysdir
->path
, SYSFS_PATH_MAX
);
629 strcat(file_path
, "/");
630 strcat(file_path
, dirent
->d_name
);
631 if ((sysfs_path_is_file(file_path
)) == 0)
632 retval
= add_attribute(sysdir
, file_path
);
639 * sysfs_read_dir_links: grabs links in a specific directory
640 * @sysdir: sysfs directory to read links
641 * returns 0 with success and -1 with error.
643 int sysfs_read_dir_links(struct sysfs_directory
*sysdir
)
646 struct dirent
*dirent
= NULL
;
647 unsigned char file_path
[SYSFS_PATH_MAX
];
650 if (sysdir
== NULL
) {
654 dir
= opendir(sysdir
->path
);
656 dprintf("Error opening directory %s\n", sysdir
->path
);
659 while(((dirent
= readdir(dir
)) != NULL
) && retval
== 0) {
660 if (0 == strcmp(dirent
->d_name
, "."))
662 if (0 == strcmp(dirent
->d_name
, ".."))
664 memset(file_path
, 0, SYSFS_PATH_MAX
);
665 strncpy(file_path
, sysdir
->path
, SYSFS_PATH_MAX
);
666 strcat(file_path
, "/");
667 strcat(file_path
, dirent
->d_name
);
668 if ((sysfs_path_is_link(file_path
)) == 0) {
669 retval
= add_link(sysdir
, file_path
);
679 * sysfs_read_dir_subdirs: grabs subdirs in a specific directory
680 * @sysdir: sysfs directory to read links
681 * returns 0 with success and -1 with error.
683 int sysfs_read_dir_subdirs(struct sysfs_directory
*sysdir
)
686 struct dirent
*dirent
= NULL
;
687 unsigned char file_path
[SYSFS_PATH_MAX
];
690 if (sysdir
== NULL
) {
694 dir
= opendir(sysdir
->path
);
696 dprintf("Error opening directory %s\n", sysdir
->path
);
699 while(((dirent
= readdir(dir
)) != NULL
) && retval
== 0) {
700 if (0 == strcmp(dirent
->d_name
, "."))
702 if (0 == strcmp(dirent
->d_name
, ".."))
704 memset(file_path
, 0, SYSFS_PATH_MAX
);
705 strncpy(file_path
, sysdir
->path
, SYSFS_PATH_MAX
);
706 strcat(file_path
, "/");
707 strcat(file_path
, dirent
->d_name
);
708 if ((sysfs_path_is_dir(file_path
)) == 0)
709 retval
= add_subdirectory(sysdir
, file_path
);
716 * sysfs_read_directory: grabs attributes, links, and subdirectories
717 * @sysdir: sysfs directory to open
718 * returns 0 with success and -1 with error.
720 int sysfs_read_directory(struct sysfs_directory
*sysdir
)
723 struct dirent
*dirent
= NULL
;
725 unsigned char file_path
[SYSFS_PATH_MAX
];
728 if (sysdir
== NULL
) {
732 dir
= opendir(sysdir
->path
);
734 dprintf("Error opening directory %s\n", sysdir
->path
);
737 while(((dirent
= readdir(dir
)) != NULL
) && retval
== 0) {
738 if (0 == strcmp(dirent
->d_name
, "."))
740 if (0 == strcmp(dirent
->d_name
, ".."))
742 memset(file_path
, 0, SYSFS_PATH_MAX
);
743 strncpy(file_path
, sysdir
->path
, SYSFS_PATH_MAX
);
744 strcat(file_path
, "/");
745 strcat(file_path
, dirent
->d_name
);
746 if ((lstat(file_path
, &astats
)) != 0) {
747 dprintf("stat failed\n");
750 if (S_ISDIR(astats
.st_mode
))
751 retval
= add_subdirectory(sysdir
, file_path
);
753 else if (S_ISLNK(astats
.st_mode
))
754 retval
= add_link(sysdir
, file_path
);
756 else if (S_ISREG(astats
.st_mode
))
757 retval
= add_attribute(sysdir
, file_path
);
764 * sysfs_refresh_dir_attributes: Refresh attributes list
765 * @sysdir: directory whose list of attributes to refresh
766 * Returns 0 on success, 1 on failure
768 int sysfs_refresh_dir_attributes(struct sysfs_directory
*sysdir
)
770 if (sysdir
== NULL
) {
774 if ((sysfs_path_is_dir(sysdir
->path
)) != 0) {
775 dprintf("Invalid path to directory %s\n", sysdir
->path
);
779 if (sysdir
->attributes
!= NULL
) {
780 dlist_destroy(sysdir
->attributes
);
781 sysdir
->attributes
= NULL
;
783 if ((sysfs_read_dir_attributes(sysdir
)) != 0) {
784 dprintf("Error refreshing attributes for directory %s\n",
792 * sysfs_refresh_dir_links: Refresh links list
793 * @sysdir: directory whose list of links to refresh
794 * Returns 0 on success, 1 on failure
796 int sysfs_refresh_dir_links(struct sysfs_directory
*sysdir
)
798 if (sysdir
== NULL
) {
802 if ((sysfs_path_is_dir(sysdir
->path
)) != 0) {
803 dprintf("Invalid path to directory %s\n", sysdir
->path
);
807 if (sysdir
->links
!= NULL
) {
808 dlist_destroy(sysdir
->links
);
809 sysdir
->links
= NULL
;
811 if ((sysfs_read_dir_links(sysdir
)) != 0) {
812 dprintf("Error refreshing links for directory %s\n",
820 * sysfs_refresh_dir_subdirs: Refresh subdirs list
821 * @sysdir: directory whose list of subdirs to refresh
822 * Returns 0 on success, 1 on failure
824 int sysfs_refresh_dir_subdirs(struct sysfs_directory
*sysdir
)
826 if (sysdir
== NULL
) {
830 if ((sysfs_path_is_dir(sysdir
->path
)) != 0) {
831 dprintf("Invalid path to directory %s\n", sysdir
->path
);
835 if (sysdir
->subdirs
!= NULL
) {
836 dlist_destroy(sysdir
->subdirs
);
837 sysdir
->subdirs
= NULL
;
839 if ((sysfs_read_dir_subdirs(sysdir
)) != 0) {
840 dprintf("Error refreshing subdirs for directory %s\n",
848 * sysfs_get_directory_attribute: retrieves attribute attrname from current
850 * @dir: directory to retrieve attribute from
851 * @attrname: name of attribute to look for
852 * returns sysfs_attribute if found and NULL if not found
854 struct sysfs_attribute
*sysfs_get_directory_attribute
855 (struct sysfs_directory
*dir
, unsigned char *attrname
)
857 struct sysfs_attribute
*attr
= NULL
;
858 unsigned char new_path
[SYSFS_PATH_MAX
];
860 if (dir
== NULL
|| attrname
== NULL
) {
865 if (dir
->attributes
== NULL
)
866 if ((sysfs_read_dir_attributes(dir
) != 0)
867 || (dir
->attributes
== NULL
))
870 attr
= (struct sysfs_attribute
*)dlist_find_custom
871 (dir
->attributes
, attrname
, dir_attribute_name_equal
);
873 if ((sysfs_read_attribute(attr
)) != 0) {
874 dprintf("Error reading attribute %s\n", attr
->name
);
878 memset(new_path
, 0, SYSFS_PATH_MAX
);
879 strcpy(new_path
, dir
->path
);
880 strcat(new_path
, "/");
881 strcat(new_path
, attrname
);
882 if ((sysfs_path_is_file(new_path
)) == 0) {
883 if ((add_attribute(dir
, new_path
)) == 0) {
884 attr
= (struct sysfs_attribute
*)
885 dlist_find_custom(dir
->attributes
,
886 attrname
, dir_attribute_name_equal
);
895 * sysfs_get_directory_link: retrieves link from one directory list
896 * @dir: directory to retrieve link from
897 * @linkname: name of link to look for
898 * returns reference to sysfs_link if found and NULL if not found
900 struct sysfs_link
*sysfs_get_directory_link
901 (struct sysfs_directory
*dir
, unsigned char *linkname
)
903 if (dir
== NULL
|| linkname
== NULL
) {
907 if (dir
->links
== NULL
) {
908 if ((sysfs_read_dir_links(dir
) != 0) || (dir
->links
== NULL
))
911 if ((sysfs_refresh_dir_links(dir
)) != 0)
915 return (struct sysfs_link
*)dlist_find_custom(dir
->links
,
916 linkname
, dir_link_name_equal
);
920 * sysfs_get_subdirectory: retrieves subdirectory by name.
921 * @dir: directory to search for subdirectory.
922 * @subname: subdirectory name to get.
923 * returns reference to subdirectory or NULL if not found
925 struct sysfs_directory
*sysfs_get_subdirectory(struct sysfs_directory
*dir
,
926 unsigned char *subname
)
928 struct sysfs_directory
*sub
= NULL
, *cursub
= NULL
;
930 if (dir
== NULL
|| subname
== NULL
) {
935 if (dir
->subdirs
== NULL
)
936 if (sysfs_read_dir_subdirs(dir
) != 0)
939 sub
= (struct sysfs_directory
*)dlist_find_custom(dir
->subdirs
,
940 subname
, dir_subdir_name_equal
);
944 if (dir
->subdirs
!= NULL
) {
945 dlist_for_each_data(dir
->subdirs
, cursub
,
946 struct sysfs_directory
) {
947 if (cursub
->subdirs
== NULL
) {
948 if (sysfs_read_dir_subdirs(cursub
) != 0)
950 if (cursub
->subdirs
== NULL
)
953 sub
= sysfs_get_subdirectory(cursub
, subname
);
962 * sysfs_get_subdirectory_link: looks through all subdirs for specific link.
963 * @dir: directory and subdirectories to search for link.
964 * @linkname: link name to get.
965 * returns reference to link or NULL if not found
967 struct sysfs_link
*sysfs_get_subdirectory_link(struct sysfs_directory
*dir
,
968 unsigned char *linkname
)
970 struct sysfs_directory
*cursub
= NULL
;
971 struct sysfs_link
*ln
= NULL
;
973 if (dir
== NULL
|| linkname
== NULL
) {
978 ln
= sysfs_get_directory_link(dir
, linkname
);
982 if (dir
->subdirs
== NULL
)
983 if (sysfs_read_dir_subdirs(dir
) != 0)
986 if (dir
->subdirs
!= NULL
) {
987 dlist_for_each_data(dir
->subdirs
, cursub
,
988 struct sysfs_directory
) {
989 ln
= sysfs_get_subdirectory_link(cursub
, linkname
);
998 * sysfs_get_dir_attributes: returns dlist of directory attributes
999 * @dir: directory to retrieve attributes from
1000 * returns dlist of attributes or NULL
1002 struct dlist
*sysfs_get_dir_attributes(struct sysfs_directory
*dir
)
1009 if (dir
->attributes
== NULL
) {
1010 if (sysfs_read_dir_attributes(dir
) != 0)
1014 return (dir
->attributes
);
1018 * sysfs_get_dir_links: returns dlist of directory links
1019 * @dir: directory to return links for
1020 * returns dlist of links or NULL
1022 struct dlist
*sysfs_get_dir_links(struct sysfs_directory
*dir
)
1029 if (dir
->links
== NULL
) {
1030 if (sysfs_read_dir_links(dir
) != 0)
1034 return (dir
->links
);
1038 * sysfs_get_dir_subdirs: returns dlist of directory subdirectories
1039 * @dir: directory to return subdirs for
1040 * returns dlist of subdirs or NULL
1042 struct dlist
*sysfs_get_dir_subdirs(struct sysfs_directory
*dir
)
1049 if (dir
->subdirs
== NULL
) {
1050 if (sysfs_read_dir_subdirs(dir
) != 0)
1054 return (dir
->subdirs
);