/*
- * syfs_dir.c
+ * sysfs_dir.c
*
* Directory utility functions for libsysfs
*
- * Copyright (C) 2003 International Business Machines, Inc.
+ * Copyright (C) IBM Corp. 2003-2005
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
#include "libsysfs.h"
#include "sysfs.h"
+static int sort_char(void *new, void *old)
+{
+ return ((strncmp((char *)new, (char *)old,
+ strlen((char *)new))) < 0 ? 1 : 0);
+}
+
+/**
+ * sysfs_del_name: free function for sysfs_open_subsystem_list
+ * @name: memory area to be freed
+ */
+static void sysfs_del_name(void *name)
+{
+ free(name);
+}
+
+/**
+ * sysfs_del_attribute: routine for dlist integration
+ */
+static void sysfs_del_attribute(void *attr)
+{
+ sysfs_close_attribute((struct sysfs_attribute *)attr);
+}
+
+/**
+ * attr_name_equal: compares attributes by name
+ * @a: attribute name for comparison
+ * @b: sysfs_attribute to be compared.
+ * returns 1 if a==b->name or 0 if not equal
+ */
+static int attr_name_equal(void *a, void *b)
+{
+ if (!a || !b)
+ return 0;
+
+ if (strcmp(((char *)a), ((struct sysfs_attribute *)b)->name) == 0)
+ return 1;
+
+ return 0;
+}
+
/**
* sysfs_close_attribute: closes and cleans up attribute
* @sysattr: attribute to close.
*/
void sysfs_close_attribute(struct sysfs_attribute *sysattr)
{
- if (sysattr != NULL) {
- if (sysattr->value != NULL)
+ if (sysattr) {
+ if (sysattr->value)
free(sysattr->value);
free(sysattr);
}
{
struct sysfs_attribute *sysattr = NULL;
struct stat fileinfo;
-
- if (path == NULL) {
+
+ if (!path) {
errno = EINVAL;
return NULL;
}
sysattr = alloc_attribute();
- if (sysattr == NULL) {
- dprintf(stderr, "Error allocating attribute at %s\n", path);
+ if (!sysattr) {
+ dprintf("Error allocating attribute at %s\n", path);
return NULL;
}
- strncpy(sysattr->path, path, sizeof(sysattr->path));
+ if (sysfs_get_name_from_path(path, sysattr->name,
+ SYSFS_NAME_LEN) != 0) {
+ dprintf("Error retrieving attrib name from path: %s\n", path);
+ sysfs_close_attribute(sysattr);
+ return NULL;
+ }
+ safestrcpy(sysattr->path, path);
if ((stat(sysattr->path, &fileinfo)) != 0) {
- perror("stat");
+ dprintf("Stat failed: No such attribute?\n");
sysattr->method = 0;
+ free(sysattr);
+ sysattr = NULL;
} else {
if (fileinfo.st_mode & S_IRUSR)
sysattr->method |= SYSFS_METHOD_SHOW;
{
char *fbuf = NULL;
char *vbuf = NULL;
- size_t length = 0;
- int pgsize = 0;
+ ssize_t length = 0;
+ long pgsize = 0;
int fd;
- if (sysattr == NULL) {
+ if (!sysattr) {
errno = EINVAL;
return -1;
}
if (!(sysattr->method & SYSFS_METHOD_SHOW)) {
- dprintf (stderr, "Show method not supported for attribute %s\n",
+ dprintf("Show method not supported for attribute %s\n",
sysattr->path);
+ errno = EACCES;
return -1;
}
- pgsize = getpagesize();
+ pgsize = sysconf(_SC_PAGESIZE);
fbuf = (char *)calloc(1, pgsize+1);
- if (fbuf == NULL) {
- perror("calloc");
+ if (!fbuf) {
+ dprintf("calloc failed\n");
return -1;
}
if ((fd = open(sysattr->path, O_RDONLY)) < 0) {
- dprintf (stderr, "Error reading attribute %s\n", sysattr->path);
+ dprintf("Error reading attribute %s\n", sysattr->path);
free(fbuf);
return -1;
}
length = read(fd, fbuf, pgsize);
if (length < 0) {
- dprintf (stderr, "Error reading from attribute %s\n",
- sysattr->path);
+ dprintf("Error reading from attribute %s\n", sysattr->path);
close(fd);
free(fbuf);
return -1;
}
+ if (sysattr->len > 0) {
+ if ((sysattr->len == length) &&
+ (!(strncmp(sysattr->value, fbuf, length)))) {
+ close(fd);
+ free(fbuf);
+ return 0;
+ }
+ free(sysattr->value);
+ }
sysattr->len = length;
close(fd);
vbuf = (char *)realloc(fbuf, length+1);
- if (vbuf == NULL) {
- perror("realloc");
+ if (!vbuf) {
+ dprintf("realloc failed\n");
free(fbuf);
return -1;
}
}
/**
- * sysfs_read_attribute_value: given path to attribute, return its value.
- * values can be up to a pagesize, if buffer is smaller the value will
- * be truncated.
- * @attrpath: sysfs path to attribute
- * @value: buffer to put value
- * @vsize: size of value buffer
+ * sysfs_write_attribute: write value to the attribute
+ * @sysattr: attribute to write
+ * @new_value: value to write
+ * @len: length of "new_value"
* returns 0 with success and -1 with error.
*/
-int sysfs_read_attribute_value(const char *attrpath, char *value, size_t vsize)
+int sysfs_write_attribute(struct sysfs_attribute *sysattr,
+ const char *new_value, size_t len)
{
- struct sysfs_attribute *attr = NULL;
- size_t length = 0;
+ int fd;
+ int length;
- if (attrpath == NULL || value == NULL) {
+ if (!sysattr || !new_value || len == 0) {
errno = EINVAL;
return -1;
}
- attr = sysfs_open_attribute(attrpath);
- if (attr == NULL) {
- dprintf(stderr, "Invalid attribute path %s\n", attrpath);
- errno = EINVAL;
+ if (!(sysattr->method & SYSFS_METHOD_STORE)) {
+ dprintf ("Store method not supported for attribute %s\n",
+ sysattr->path);
+ errno = EACCES;
return -1;
}
- if((sysfs_read_attribute(attr)) != 0 || attr->value == NULL) {
- dprintf(stderr, "Error reading from attribute %s\n", attrpath);
- sysfs_close_attribute(attr);
+ if (sysattr->method & SYSFS_METHOD_SHOW) {
+ /*
+ * read attribute again to see if we can get an updated value
+ */
+ if ((sysfs_read_attribute(sysattr))) {
+ dprintf("Error reading attribute\n");
+ return -1;
+ }
+ if ((strncmp(sysattr->value, new_value, sysattr->len)) == 0) {
+ dprintf("Attr %s already has the requested value %s\n",
+ sysattr->name, new_value);
+ return 0;
+ }
+ }
+ /*
+ * open O_WRONLY since some attributes have no "read" but only
+ * "write" permission
+ */
+ if ((fd = open(sysattr->path, O_WRONLY)) < 0) {
+ dprintf("Error reading attribute %s\n", sysattr->path);
return -1;
}
- length = strlen(attr->value);
- if (length > vsize)
- dprintf(stderr,
- "Value length %d is larger than supplied buffer %d\n",
- length, vsize);
- strncpy(value, attr->value, vsize);
- sysfs_close_attribute(attr);
-
- return 0;
-}
-/**
- * sysfs_get_value_from_attrbutes: given a linked list of attributes and an
- * attribute name, return its value
- * @attr: attribute to search
- * @name: name to look for
- * returns char * value - could be NULL
- */
-char *sysfs_get_value_from_attributes(struct sysfs_attribute *attr,
- const char *name)
-{
- struct sysfs_attribute *cur = NULL;
- char tmpname[SYSFS_NAME_LEN];
-
- if (attr == NULL || name == NULL) {
- errno = EINVAL;
- return NULL;
- }
- cur = attr;
- while (cur != NULL) {
- memset(tmpname, 0, SYSFS_NAME_LEN);
- if ((sysfs_get_name_from_path(cur->path, tmpname,
- SYSFS_NAME_LEN)) != 0) {
- cur = cur->next;
- continue;
+ length = write(fd, new_value, len);
+ if (length < 0) {
+ dprintf("Error writing to the attribute %s - invalid value?\n",
+ sysattr->name);
+ close(fd);
+ return -1;
+ } else if ((unsigned int)length != len) {
+ dprintf("Could not write %d bytes to attribute %s\n",
+ len, sysattr->name);
+ /*
+ * since we could not write user supplied number of bytes,
+ * restore the old value if one available
+ */
+ if (sysattr->method & SYSFS_METHOD_SHOW) {
+ length = write(fd, sysattr->value, sysattr->len);
+ close(fd);
+ return -1;
}
- if (strcmp(tmpname, name) == 0)
- return cur->value;
- cur = cur->next;
- }
- return NULL;
-}
-
-/**
- * add_subdir_to_dir: adds subdirectory to directory's subdirs
- * @sysdir: directory to add subdir to
- * @subdir: subdirectory to add.
- */
-static void add_subdir_to_dir(struct sysfs_directory *sysdir,
- struct sysfs_directory *subdir)
-{
- if (sysdir != NULL && subdir != NULL) {
- subdir->next = sysdir->subdirs;
- sysdir->subdirs = subdir;
}
-}
-/**
- * add_attr_to_dir: adds attribute to directory's attributes
- * @sysdir: directory to add attribute to
- * @sysattr: attribute to add.
- */
-static void add_attr_to_dir(struct sysfs_directory *sysdir,
- struct sysfs_attribute *sysattr)
-{
- if (sysdir != NULL && sysattr != NULL) {
- sysattr->next = sysdir->attributes;
- sysdir->attributes = sysattr;
+ /*
+ * Validate length that has been copied. Alloc appropriate area
+ * in sysfs_attribute. Verify first if the attribute supports reading
+ * (show method). If it does not, do not bother
+ */
+ if (sysattr->method & SYSFS_METHOD_SHOW) {
+ if (length != sysattr->len) {
+ sysattr->value = (char *)realloc
+ (sysattr->value, length);
+ sysattr->len = length;
+ safestrcpymax(sysattr->value, new_value, length);
+ } else {
+ /*"length" of the new value is same as old one */
+ safestrcpymax(sysattr->value, new_value, length);
+ }
}
+
+ close(fd);
+ return 0;
}
/**
- * sysfs_close_dlink: closes and cleans up directory link.
- * @dlink: directory link to close.
+ * add_attribute: open and add attribute at path to given directory
+ * @dev: device whose attribute is to be added
+ * @path: path to attribute
+ * returns pointer to attr added with success and NULL with error.
*/
-void sysfs_close_dlink(struct sysfs_dlink *dlink)
+static struct sysfs_attribute *add_attribute(void *dev, const char *path)
{
- if (dlink != NULL) {
- dlink->next = NULL;
- if (dlink->target != NULL)
- sysfs_close_directory(dlink->target);
- free(dlink);
- }
-}
+ struct sysfs_attribute *attr;
-/**
- * add_dlink_to_dir: adds directory link to directory's links list.
- * @sysdir: directory to add it to.
- * @dlink: link to add.
- */
-static void add_dlink_to_dir(struct sysfs_directory *sysdir,
- struct sysfs_dlink *dlink)
-{
- if (sysdir != NULL && dlink != NULL) {
- dlink->next = sysdir->links;
- sysdir->links = dlink;
+ attr = sysfs_open_attribute(path);
+ if (!attr) {
+ dprintf("Error opening attribute %s\n", path);
+ return NULL;
}
-}
-
-/**
- * sysfs_close_directory: closes directory, cleans up attributes and links
- * @sysdir: sysfs_directory to close
- */
-void sysfs_close_directory(struct sysfs_directory *sysdir)
-{
- struct sysfs_directory *sdir = NULL, *dnext = NULL;
- struct sysfs_dlink *dlink = NULL, *nextl = NULL;
- struct sysfs_attribute *attr = NULL, *anext = NULL;
-
- if (sysdir != NULL) {
- if (sysdir->subdirs != NULL) {
- for (sdir = sysdir->subdirs; sdir != NULL;
- sdir = dnext) {
- dnext = sdir->next;
- sysfs_close_directory(sdir);
- }
- }
- if (sysdir->links != NULL) {
- for (dlink = sysdir->links; dlink != NULL;
- dlink = nextl) {
- nextl = dlink->next;
- sysfs_close_dlink(dlink);
- }
- }
- if (sysdir->attributes != NULL) {
- for (attr = sysdir->attributes; attr != NULL;
- attr = anext) {
- anext = attr->next;
- /* sysfs_close_attribute(attr); */
- if (attr->value != NULL)
- free(attr->value);
- free(attr);
- }
+ if (attr->method & SYSFS_METHOD_SHOW) {
+ if (sysfs_read_attribute(attr)) {
+ dprintf("Error reading attribute %s\n", path);
+ sysfs_close_attribute(attr);
+ return NULL;
}
- free(sysdir);
}
-}
-/**
- * alloc_directory: allocates and initializes directory structure
- * returns struct sysfs_directory with success or NULL with error.
- */
-static struct sysfs_directory *alloc_directory(void)
-{
- return (struct sysfs_directory *)
- calloc(1, sizeof(struct sysfs_directory));
-}
+ if (!((struct sysfs_device *)dev)->attrlist) {
+ ((struct sysfs_device *)dev)->attrlist = dlist_new_with_delete
+ (sizeof(struct sysfs_attribute), sysfs_del_attribute);
+ }
+ dlist_unshift_sorted(((struct sysfs_device *)dev)->attrlist,
+ attr, sort_list);
-/**
- * alloc_dlink: allocates and initializes directory link structure
- * returns struct sysfs_dlink with success or NULL with error.
- */
-static struct sysfs_dlink *alloc_dlink(void)
-{
- return (struct sysfs_dlink *)calloc(1, sizeof(struct sysfs_dlink));
+ return attr;
}
-/**
- * sysfs_open_directory: opens a sysfs directory, creates dir struct, and
- * returns.
- * @path: path of directory to open.
- * returns: struct sysfs_directory * with success and NULL on error.
+/*
+ * get_attribute - given a sysfs_* struct and a name, return the
+ * sysfs_attribute corresponding to "name"
+ * returns sysfs_attribute on success and NULL on error
*/
-struct sysfs_directory *sysfs_open_directory(const char *path)
+struct sysfs_attribute *get_attribute(void *dev, const char *name)
{
- struct sysfs_directory *sdir = NULL;
+ struct sysfs_attribute *cur = NULL;
+ char path[SYSFS_PATH_MAX];
- if (path == NULL) {
+ if (!dev || !name) {
errno = EINVAL;
return NULL;
}
- sdir = alloc_directory();
- if (sdir == NULL) {
- dprintf(stderr, "Error allocating directory %s\n", path);
- return NULL;
- }
- strncpy(sdir->path, path, sizeof(sdir->path));
- return sdir;
+ if (((struct sysfs_device *)dev)->attrlist) {
+ /* check if attr is already in the list */
+ cur = (struct sysfs_attribute *)dlist_find_custom
+ ((((struct sysfs_device *)dev)->attrlist),
+ (void *)name, attr_name_equal);
+ if (cur)
+ return cur;
+ }
+ safestrcpymax(path, ((struct sysfs_device *)dev)->path,
+ SYSFS_PATH_MAX);
+ safestrcatmax(path, "/", SYSFS_PATH_MAX);
+ safestrcatmax(path, name, SYSFS_PATH_MAX);
+ if (!(sysfs_path_is_file(path)))
+ cur = add_attribute((void *)dev, path);
+ return cur;
}
/**
- * sysfs_open_dlink: opens a sysfs directory link, creates struct, and returns
- * @path: path of link to open.
- * returns: struct sysfs_dlink * with success and NULL on error.
+ * read_dir_links: grabs links in a specific directory
+ * @sysdir: sysfs directory to read
+ * returns list of link names with success and NULL with error.
*/
-struct sysfs_dlink *sysfs_open_dlink(const char *linkpath)
+struct dlist *read_dir_links(const char *path)
{
- struct sysfs_dlink *dlink = NULL;
- struct sysfs_directory *tdir = NULL;
- char name[SYSFS_NAME_LEN];
- char target[SYSFS_PATH_MAX];
+ DIR *dir = NULL;
+ struct dirent *dirent = NULL;
+ char file_path[SYSFS_PATH_MAX], *linkname;
+ struct dlist *linklist = NULL;
- if (linkpath == NULL) {
+ if (!path) {
errno = EINVAL;
return NULL;
}
-
- memset(name, 0, SYSFS_NAME_LEN);
- memset(target, 0, SYSFS_PATH_MAX);
- if ((sysfs_get_name_from_path(linkpath, name, SYSFS_NAME_LEN)) != 0
- || (sysfs_get_link(linkpath, target, SYSFS_PATH_MAX)) != 0) {
- errno = EINVAL;
- dprintf(stderr, "Invalid link path %s\n", linkpath);
+ dir = opendir(path);
+ if (!dir) {
+ dprintf("Error opening directory %s\n", path);
return NULL;
}
- dlink = alloc_dlink();
- if (dlink == NULL) {
- dprintf(stderr,
- "Error allocating directory link %s\n", linkpath);
- return NULL;
+ while ((dirent = readdir(dir)) != NULL) {
+ if (0 == strcmp(dirent->d_name, "."))
+ continue;
+ if (0 == strcmp(dirent->d_name, ".."))
+ continue;
+ memset(file_path, 0, SYSFS_PATH_MAX);
+ safestrcpy(file_path, path);
+ safestrcat(file_path, "/");
+ safestrcat(file_path, dirent->d_name);
+ if ((sysfs_path_is_link(file_path)) == 0) {
+ if (!linklist) {
+ linklist = dlist_new_with_delete
+ (SYSFS_NAME_LEN, sysfs_del_name);
+ if (!linklist) {
+ dprintf("Error creating list\n");
+ return NULL;
+ }
+ }
+ linkname = (char *)calloc(1, SYSFS_NAME_LEN);
+ safestrcpymax(linkname, dirent->d_name, SYSFS_NAME_LEN);
+ dlist_unshift_sorted(linklist, linkname, sort_char);
+ }
}
- strcpy(dlink->name, name);
- tdir = sysfs_open_directory(target);
- if (tdir == NULL) {
- dprintf(stderr, "Invalid directory link target %s\n", target);
- sysfs_close_dlink(dlink);
- return NULL;
- }
- dlink->target = tdir;
-
- return dlink;
+ closedir(dir);
+ return linklist;
}
/**
- * sysfs_read_directory: grabs attributes, links, and subdirectories
- * @sysdir: sysfs directory to open
- * returns 0 with success and -1 with error.
+ * read_dir_subdirs: grabs subdirs in a specific directory
+ * @sysdir: sysfs directory to read
+ * returns list of directory names with success and NULL with error.
*/
-int sysfs_read_directory(struct sysfs_directory *sysdir)
+struct dlist *read_dir_subdirs(const char *path)
{
DIR *dir = NULL;
struct dirent *dirent = NULL;
- struct stat astats;
- struct sysfs_attribute *attr = NULL;
- struct sysfs_directory *subdir = NULL;
- struct sysfs_dlink *dlink = NULL;
- char file_path[SYSFS_PATH_MAX];
- int retval = 0;
+ char file_path[SYSFS_PATH_MAX], *dir_name;
+ struct dlist *dirlist = NULL;
- if (sysdir == NULL) {
+ if (!path) {
errno = EINVAL;
- return -1;
+ return NULL;
}
- dir = opendir(sysdir->path);
- if (dir == NULL) {
- perror("opendir");
- return -1;
+ dir = opendir(path);
+ if (!dir) {
+ dprintf("Error opening directory %s\n", path);
+ return NULL;
}
- while(((dirent = readdir(dir)) != NULL) && retval == 0) {
+ while ((dirent = readdir(dir)) != NULL) {
if (0 == strcmp(dirent->d_name, "."))
continue;
if (0 == strcmp(dirent->d_name, ".."))
continue;
memset(file_path, 0, SYSFS_PATH_MAX);
- strncpy(file_path, sysdir->path, sizeof(file_path));
- strncat(file_path, "/", sizeof(file_path));
- strncat(file_path, dirent->d_name, sizeof(file_path));
- if ((lstat(file_path, &astats)) != 0) {
- perror("stat");
- continue;
- }
- if (S_ISREG(astats.st_mode)) {
- attr = sysfs_open_attribute(file_path);
- if (attr == NULL) {
- dprintf (stderr, "Error opening attribute %s\n",
- file_path);
- retval = -1;
- break;
- }
- if (attr->method & SYSFS_METHOD_SHOW) {
- if ((sysfs_read_attribute(attr)) != 0) {
- dprintf (stderr,
- "Error reading attribute %s\n",
- file_path);
- sysfs_close_attribute(attr);
- continue;
+ safestrcpy(file_path, path);
+ safestrcat(file_path, "/");
+ safestrcat(file_path, dirent->d_name);
+ if ((sysfs_path_is_dir(file_path)) == 0) {
+ if (!dirlist) {
+ dirlist = dlist_new_with_delete
+ (SYSFS_NAME_LEN, sysfs_del_name);
+ if (!dirlist) {
+ dprintf("Error creating list\n");
+ return NULL;
}
}
- add_attr_to_dir(sysdir, attr);
- } else if (S_ISDIR(astats.st_mode)) {
- subdir = sysfs_open_directory(file_path);
- if (subdir == NULL) {
- dprintf (stderr, "Error opening directory %s\n",
- file_path);
- retval = -1;
- break;
- }
- add_subdir_to_dir(sysdir, subdir);
- } else if (S_ISLNK(astats.st_mode)) {
- dlink = sysfs_open_dlink(file_path);
- if (dlink == NULL) {
- dprintf(stderr, "Error opening link %s\n",
- file_path);
- retval = -1;
- break;
- }
- add_dlink_to_dir(sysdir, dlink);
+ dir_name = (char *)calloc(1, SYSFS_NAME_LEN);
+ safestrcpymax(dir_name, dirent->d_name, SYSFS_NAME_LEN);
+ dlist_unshift_sorted(dirlist, dir_name, sort_char);
}
}
closedir(dir);
- return(retval);
+ return dirlist;
}
/**
- * sysfs_read_dlinks: reads a directory link's target directory. Can
- * supply a linked list of links.
- * @dlink: directory link to read.
- * returns 0 with success or -1 with error.
+ * get_attributes_list: build a list of attributes for the given device
+ * @dev: devices whose attributes list is required
+ * returns dlist of attributes on success and NULL on failure
*/
-int sysfs_read_dlinks(struct sysfs_dlink *dlink)
+struct dlist *get_attributes_list(void *dev)
{
- struct sysfs_dlink *cur = NULL;
+ DIR *dir = NULL;
+ struct dirent *dirent = NULL;
+ struct sysfs_attribute *attr = NULL;
+ char file_path[SYSFS_PATH_MAX], path[SYSFS_PATH_MAX];
- if (dlink == NULL || dlink->target == NULL) {
+ if (!dev) {
errno = EINVAL;
- return -1;
+ return NULL;
}
- cur = dlink;
- while (cur != NULL) {
- if ((sysfs_read_directory(cur->target)) != 0) {
- dprintf(stderr,
- "Error reading directory link target %s\n",
- dlink->name);
- return -1;
+ memset(path, 0, SYSFS_PATH_MAX);
+ safestrcpy(path, ((struct sysfs_device *)dev)->path);
+ dir = opendir(path);
+ if (!dir) {
+ dprintf("Error opening directory %s\n", path);
+ return NULL;
+ }
+ while ((dirent = readdir(dir)) != NULL) {
+ if (0 == strcmp(dirent->d_name, "."))
+ continue;
+ if (0 == strcmp(dirent->d_name, ".."))
+ continue;
+ memset(file_path, 0, SYSFS_PATH_MAX);
+ safestrcpy(file_path, path);
+ safestrcat(file_path, "/");
+ safestrcat(file_path, dirent->d_name);
+ if ((sysfs_path_is_file(file_path)) == 0) {
+ if (((struct sysfs_device *)dev)->attrlist) {
+ /* check if attr is already in the list */
+ attr = (struct sysfs_attribute *)
+ dlist_find_custom
+ ((((struct sysfs_device *)dev)->attrlist),
+ (void *)dirent->d_name, attr_name_equal);
+ if (attr)
+ continue;
+ else
+ add_attribute(dev, file_path);
+ } else
+ attr = add_attribute(dev, file_path);
}
- cur = cur->next;
}
-
- return 0;
+ closedir(dir);
+ return ((struct sysfs_device *)dev)->attrlist;
}
~ianmdlvl / elogind.git / blobdiff