[PATCH] add udevinfo to install target of Makefile

[elogind.git] / libsysfs / sysfs_utils.c

diff --git a/libsysfs/sysfs_utils.c b/libsysfs/sysfs_utils.c
index 009ae94efaa8534f1f75f67f1118c79729761ede..f1f82361d024f7eaa9dbc1becc7a78df027e0cea 100644 (file)
--- a/libsysfs/sysfs_utils.c
+++ b/libsysfs/sysfs_utils.c
@@ -26,6 +26,30 @@
 #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
@@ -72,27 +96,13 @@ static int sysfs_get_fs_mnt_path(const unsigned char *fs_type,
                errno = EINVAL;
                ret = -1;
        }
+       if ((sysfs_remove_trailing_slash(mnt_path)) != 0)
+               ret = -1;
+       
        return ret;
 #endif
 }
 
-/*
- * sysfs_trailing_slash: checks if there's a trailing slash to path
- * @path: path to check
- * returns 1 if true and 0 if not
- */
-int sysfs_trailing_slash(unsigned char *path)
-{
-       unsigned char *s = NULL;
-
-       if (path == NULL)
-               return 0;
-       s = &path[strlen(path)-1];
-       if (strncmp(s, "/", 1) == 0)
-               return 1;
-       return 0;
-}
-
 /*
  * sysfs_get_mnt_path: Gets the sysfs mount point.
  * @mnt_path: place to put "sysfs" mount point
@@ -109,9 +119,11 @@ int sysfs_get_mnt_path(unsigned char *mnt_path, size_t len)
                return -1;
        }
        sysfs_path = getenv(SYSFS_PATH_ENV);
-       if (sysfs_path != NULL) 
+       if (sysfs_path != NULL) {
                strncpy(mnt_path, sysfs_path, len);
-       else
+               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;
@@ -152,7 +164,7 @@ int sysfs_get_name_from_path(const unsigned char *path, unsigned char *name,
        strncpy(name, n, len);
        return 0;
 }
-
+       
 /**
  * sysfs_get_link: returns link source
  * @path: symbolic link's path
@@ -178,32 +190,69 @@ int sysfs_get_link(const unsigned char *path, unsigned char *target, size_t len)
        if ((readlink(path, linkpath, SYSFS_PATH_MAX)) < 0) {
                return -1;
        }
-                                                                               
        d = linkpath;
-
-       /* getting rid of leading "../.." */    
-       while (*d == '/' || *d == '.') {
-               if (*d == '/')
-                       slashes++;
-               d++;
-       }
-
-       d--;
-
-       s = &devdir[strlen(devdir)-1];
-       while (s != NULL && count != (slashes+1)) {
-               s--;
-               if (*s == '/')
-                       count++;
+       /* 
+        * 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);
+                       }                       
        }
-       
-       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
@@ -245,8 +294,8 @@ struct dlist *sysfs_open_subsystem_list(unsigned char *name)
                dprintf("Error getting sysfs mount point\n");
                return NULL;
        }
-       if (sysfs_trailing_slash(sysfs_path) == 0)
-               strcat(sysfs_path, "/");
+
+       strcat(sysfs_path, "/");
        strcat(sysfs_path, name);
        dir = sysfs_open_directory(sysfs_path);
        if (dir == NULL) {
@@ -318,8 +367,7 @@ struct dlist *sysfs_open_bus_devices_list(unsigned char *name)
                return NULL;
        }
 
-       if (sysfs_trailing_slash(sysfs_path) == 0)
-               strcat(sysfs_path, "/");
+       strcat(sysfs_path, "/");
        strcat(sysfs_path, SYSFS_BUS_NAME);
        strcat(sysfs_path, "/");
        strcat(sysfs_path, name);
@@ -376,7 +424,7 @@ int sysfs_path_is_dir(const unsigned char *path)
        }
        if (S_ISDIR(astats.st_mode))
                return 0;
-
+               
        return 1;
 }
 
@@ -399,7 +447,7 @@ int sysfs_path_is_link(const unsigned char *path)
        }
        if (S_ISLNK(astats.st_mode))
                return 0;
-
+               
        return 1;
 }
 
@@ -422,6 +470,6 @@ int sysfs_path_is_file(const unsigned char *path)
        }
        if (S_ISREG(astats.st_mode))
                return 0;
-
+               
        return 1;
 }