chiark / gitweb /
[PATCH] libsysfs changes for sysfsutils 0.3.0
[elogind.git] / libsysfs / sysfs_utils.c
index a2410ab..4e96051 100644 (file)
@@ -3,7 +3,7 @@
  *
  * System utility functions for libsysfs
  *
- * Copyright (C) 2003 International Business Machines, Inc.
+ * Copyright (C) IBM Corp. 2003
  *
  *  This library is free software; you can redistribute it and/or
  *  modify it under the terms of the GNU Lesser General Public
@@ -22,6 +22,9 @@
  */
 #include "libsysfs.h"
 #include "sysfs.h"
+#ifndef __KLIBC__
+#include <mntent.h>
+#endif
 
 /**
  * sysfs_get_mnt_path: Gets the mount point for specified filesystem.
  * @len: size of mnt_path
  * returns 0 with success and -1 with error.
  */
-static int sysfs_get_fs_mnt_path(const char *fs_type, char *mnt_path
-                                size_t len)
+static int sysfs_get_fs_mnt_path(const unsigned char *fs_type
+                               unsigned char *mnt_path, size_t len)
 {
+#ifdef __KLIBC__
+       strcpy(mnt_path, "/sys");
+       return 0;
+#else
        FILE *mnt;
        struct mntent *mntent;
        int ret = 0;
@@ -45,7 +52,7 @@ static int sysfs_get_fs_mnt_path(const char *fs_type, char *mnt_path,
        }
 
        if ((mnt = setmntent(SYSFS_PROC_MNTS, "r")) == NULL) {
-               dprintf(stderr, "Error getting mount information\n");
+               dprintf("Error getting mount information\n");
                return -1;
        }
        while (ret == 0 && dirlen == 0 && (mntent = getmntent(mnt)) != NULL) {
@@ -54,19 +61,19 @@ static int sysfs_get_fs_mnt_path(const char *fs_type, char *mnt_path,
                        if (dirlen <= (len - 1)) {
                                strcpy(mnt_path, mntent->mnt_dir);
                        } else {
-                               dprintf(stderr, 
-                                       "Error - mount path too long\n");
+                               dprintf("Error - mount path too long\n");
                                ret = -1;
                        }
                }
        }
        endmntent(mnt);
        if (dirlen == 0 && ret == 0) {
-               dprintf(stderr, "Filesystem %s not found!\n", fs_type);
+               dprintf("Filesystem %s not found!\n", fs_type);
                errno = EINVAL;
                ret = -1;
        }
        return ret;
+#endif
 }
 
 /*
@@ -75,14 +82,20 @@ static int sysfs_get_fs_mnt_path(const char *fs_type, char *mnt_path,
  * @len: size of mnt_path
  * returns 0 with success and -1 with error.
  */
-int sysfs_get_mnt_path(char *mnt_path, size_t len)
+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);
+       else
+               ret = sysfs_get_fs_mnt_path(SYSFS_FSTYPE_NAME, mnt_path, len);
 
        return ret;
 }
@@ -93,15 +106,22 @@ int sysfs_get_mnt_path(char *mnt_path, size_t len)
  * @name: where to put name
  * @len: size of name
  */
-int sysfs_get_name_from_path(const char *path, char *name, size_t len)
+int sysfs_get_name_from_path(const unsigned char *path, unsigned char *name, 
+                                                               size_t len)
 {
-       char *n = NULL;
+       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 = &tmp[strlen(tmp)-1];
+       if (strncmp(n, "/", 1) == 0)
+               *n = '\0';      
+       n = strrchr(tmp, '/');
        if (n == NULL) {
                errno = EINVAL;
                return -1;
@@ -118,11 +138,12 @@ int sysfs_get_name_from_path(const char *path, char *name, size_t len)
  * @target: where to put name
  * @len: size of name
  */
-int sysfs_get_link(const char *path, char *target, size_t len)
+int sysfs_get_link(const unsigned char *path, unsigned char *target, size_t len)
 {
-       char devdir[SYSFS_PATH_MAX];
-       char linkpath[SYSFS_PATH_MAX];
-       char *d = NULL;
+       unsigned char devdir[SYSFS_PATH_MAX];
+       unsigned char linkpath[SYSFS_PATH_MAX];
+       unsigned char *d = NULL, *s = NULL;
+       int slashes = 0, count = 0;
 
        if (path == NULL || target == NULL) {
                errno = EINVAL;
@@ -131,12 +152,8 @@ int sysfs_get_link(const char *path, char *target, size_t len)
 
        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(stderr, "Sysfs not supported on this system\n");
-               return -1;
-       }
-                                                                       
        if ((readlink(path, linkpath, SYSFS_PATH_MAX)) < 0) {
                return -1;
        }
@@ -144,13 +161,179 @@ int sysfs_get_link(const char *path, char *target, size_t len)
        d = linkpath;
 
        /* getting rid of leading "../.." */    
-       while (*d == '/' || *d == '.')
+       while (*d == '/' || *d == '.') {
+               if (*d == '/')
+                       slashes++;
                d++;
+       }
 
        d--;
+
+       s = &devdir[strlen(devdir)-1];
+       while (s != NULL && count != (slashes+1)) {
+               s--;
+               if (*s == '/')
+                       count++;
+       }
        
-       strcat(devdir, d);
+       strncpy(s, d, (SYSFS_PATH_MAX-strlen(devdir)));
        strncpy(target, devdir, len);
 
        return 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_close_list: generic list free routine
+ * @list: dlist to free
+ * Returns nothing
+ */
+void sysfs_close_list(struct dlist *list)
+{
+       if (list != NULL)
+               dlist_destroy(list);
+}
+
+/**
+ * sysfs_open_subsystem_list: gets a list of all supported "name" subsystem
+ *     details from the system
+ * @name: name of the subsystem, eg., "bus", "class", "devices"
+ * Returns a dlist of supported names or NULL if subsystem not supported
+ */ 
+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;
+       struct stat astats;
+       
+       if (name == NULL)
+               return NULL;
+
+       if (sysfs_get_mnt_path(sysfs_path, SYSFS_PATH_MAX) != 0) {
+               dprintf("Error getting sysfs mount point\n");
+               return NULL;
+       }
+
+       strcat(sysfs_path, 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) {
+               dprintf("Error reading sysfs_directory at %s\n", sysfs_path);
+               sysfs_close_directory(dir);
+               return NULL;
+       }
+
+       if (dir->subdirs != NULL) {
+               list = dlist_new_with_delete(SYSFS_NAME_LEN,
+                               sysfs_del_name);
+               if (list == NULL) {
+                       dprintf("Error creating list\n");
+                       sysfs_close_directory(dir);
+                       return NULL;
+               }
+
+               dlist_for_each_data(dir->subdirs, cur,
+                               struct sysfs_directory) {
+                       subsys_name = (char *)calloc(1, SYSFS_NAME_LEN);
+                       strcpy(subsys_name, cur->name);
+                       dlist_unshift(list, subsys_name);
+               }
+       }
+       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_DIR) == 0) {
+               c = strstr(sysfs_path, SYSFS_CLASS_NAME);
+               if (c == NULL)
+                       goto out;
+               strcpy(c, SYSFS_BLOCK_NAME);
+               if ((lstat(sysfs_path, &astats)) != 0) {
+                       dprintf("stat() failed\n");
+                       goto out;
+               }
+               if (S_ISDIR(astats.st_mode)) {
+                       subsys_name = (char *)calloc(1, SYSFS_NAME_LEN);
+                       strcpy(subsys_name, SYSFS_BLOCK_NAME);
+                       dlist_unshift(list, subsys_name);
+               }
+       }
+out:
+       return list;
+}
+
+
+/**
+ * sysfs_open_bus_devices_list: gets a list of all devices on "name" bus
+ * @name: name of the subsystem, eg., "pci", "scsi", "usb"
+ * Returns a dlist of supported names or NULL if subsystem not supported
+ */ 
+struct dlist *sysfs_open_bus_devices_list(unsigned char *name)
+{
+       unsigned char sysfs_path[SYSFS_PATH_MAX], *device_name = NULL;
+       struct sysfs_directory *dir = NULL;
+       struct sysfs_link *cur = NULL;
+       struct dlist *list = NULL;
+       
+       if (name == NULL)
+               return NULL;
+
+       if (sysfs_get_mnt_path(sysfs_path, SYSFS_PATH_MAX) != 0) {
+               dprintf("Error getting sysfs mount point\n");
+               return NULL;
+       }
+
+       strcat(sysfs_path, SYSFS_BUS_DIR);
+       strcat(sysfs_path, "/");
+       strcat(sysfs_path, name);
+       strcat(sysfs_path, SYSFS_DEVICES_DIR);
+       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) {
+               dprintf("Error reading sysfs_directory at %s\n", sysfs_path);
+               sysfs_close_directory(dir);
+               return NULL;
+       }
+
+       if (dir->links != NULL) {
+               list = dlist_new_with_delete(SYSFS_NAME_LEN,
+                               sysfs_del_name);
+               if (list == NULL) {
+                       dprintf("Error creating list\n");
+                       sysfs_close_directory(dir);
+                       return NULL;
+               }
+
+               dlist_for_each_data(dir->links, cur,
+                               struct sysfs_link) {
+                       device_name = (char *)calloc(1, SYSFS_NAME_LEN);
+                       strcpy(device_name, cur->name);
+                       dlist_unshift(list, device_name);
+               }
+       }
+       sysfs_close_directory(dir);
+       return list;
+}
+