[PATCH] libsysfs changes for sysfsutils 0.3.0

[elogind.git] / libsysfs / sysfs_utils.c

diff --git a/libsysfs/sysfs_utils.c b/libsysfs/sysfs_utils.c
index 4475342433d2151262e20ea57c58e0f1005f9a0c..4e96051c780452809f087efb52bf543f3855b021 100644 (file)
--- a/libsysfs/sysfs_utils.c
+++ b/libsysfs/sysfs_utils.c
@@ -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.
@@ -33,6 +36,10 @@
 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;
@@ -66,6 +73,7 @@ static int sysfs_get_fs_mnt_path(const unsigned char *fs_type,
                ret = -1;
        }
        return ret;
+#endif
 }
 
 /*
@@ -76,12 +84,18 @@ static int sysfs_get_fs_mnt_path(const unsigned char *fs_type,
  */
 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;
 }
@@ -95,13 +109,19 @@ int sysfs_get_mnt_path(unsigned char *mnt_path, size_t len)
 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 = &tmp[strlen(tmp)-1];
+       if (strncmp(n, "/", 1) == 0)
+               *n = '\0';      
+       n = strrchr(tmp, '/');
        if (n == NULL) {
                errno = EINVAL;
                return -1;
@@ -122,7 +142,8 @@ int sysfs_get_link(const unsigned char *path, unsigned char *target, size_t len)
 {
        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;
@@ -131,12 +152,8 @@ int sysfs_get_link(const unsigned char *path, unsigned 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("Sysfs not supported on this system\n");
-               return -1;
-       }
-                                                                       
        if ((readlink(path, linkpath, SYSFS_PATH_MAX)) < 0) {
                return -1;
        }
@@ -144,12 +161,22 @@ int sysfs_get_link(const unsigned char *path, unsigned 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;
@@ -160,7 +187,7 @@ int sysfs_get_link(const unsigned char *path, unsigned char *target, size_t len)
  * 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);
 }
@@ -186,8 +213,10 @@ void sysfs_close_list(struct dlist *list)
 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;
@@ -227,6 +256,27 @@ struct dlist *sysfs_open_subsystem_list(unsigned char *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;
 }