[PATCH] experimental (very simple) SYMLINK creation

[elogind.git] / udev-add.c

diff --git a/udev-add.c b/udev-add.c
index a71d435e327db824616935020e878faed987336f..ddf432bbc7229312a7522372207898f0709786a1 100644 (file)
--- a/udev-add.c
+++ b/udev-add.c
@@ -72,6 +72,34 @@ exit:
        return retval;
 }
 
+static int create_path(char *file)
+{
+       char p[NAME_SIZE];
+       char *pos;
+       int retval;
+       struct stat stats;
+       
+       strncpy(p, file, sizeof(p));
+       pos = strchr(p+1, '/');
+       while (1) {
+               pos = strchr(pos+1, '/');
+               if (pos == NULL)
+                       break;
+               *pos = 0x00;
+               if (stat(p, &stats)) {
+                       retval = mkdir(p, 0755);
+                       if (retval) {
+                               dbg("mkdir(%s) failed with error '%s'",
+                                   p, strerror(errno));
+                               return retval;
+                       }
+                       dbg("created '%s'", p);
+               }
+               *pos = '/';
+       }
+       return 0;
+}
+
 /*
  * we possibly want to add some symlinks here
  * only numeric owner/group id's are supported
@@ -79,10 +107,14 @@ exit:
 static int create_node(struct udevice *dev)
 {
        char filename[255];
+       char linktarget[255];
        int retval = 0;
        uid_t uid = 0;
        gid_t gid = 0;
        dev_t res;
+       int i;
+       int tail;
+
 
        strncpy(filename, udev_root, sizeof(filename));
        strncat(filename, dev->name, sizeof(filename));
@@ -109,31 +141,9 @@ static int create_node(struct udevice *dev)
                return -EINVAL;
        }
 
-       /* create subdirectories if requested */
-       if (strchr(dev->name, '/')) {
-               char path[255];
-               char *pos;
-               struct stat stats;
-
-               strncpy(path, filename, sizeof(path));
-               pos = strchr(path+1, '/');
-               while (1) {
-                       pos = strchr(pos+1, '/');
-                       if (pos == NULL)
-                               break;
-                       *pos = 0x00;
-                       if (stat(path, &stats)) {
-                               retval = mkdir(path, 0755);
-                               if (retval) {
-                                       dbg("mkdir(%s) failed with error '%s'",
-                                           path, strerror(errno));
-                                       return retval;
-                               }
-                               dbg("created '%s'", path);
-                       }
-                       *pos = '/';
-               }
-       }
+       /* create parent directories if needed */
+       if (strrchr(dev->name, '/'))
+               create_path(filename);
 
        dbg("mknod(%s, %#o, %u, %u)", filename, dev->mode, dev->major, dev->minor);
        retval = mknod(filename, dev->mode, res);
@@ -179,8 +189,43 @@ static int create_node(struct udevice *dev)
                dbg("chown(%s, %u, %u)", filename, uid, gid);
                retval = chown(filename, uid, gid);
                if (retval)
-                       dbg("chown(%s, %u, %u) failed with error '%s'", filename,
-                           uid, gid, strerror(errno));
+                       dbg("chown(%s, %u, %u) failed with error '%s'",
+                           filename, uid, gid, strerror(errno));
+       }
+
+
+       /* create symlink if requested */
+       if (*dev->symlink) {
+               strncpy(filename, udev_root, sizeof(filename));
+               strncat(filename, dev->symlink, sizeof(filename));
+               dbg("symlink '%s' to node '%s' requested", filename, dev->name);
+               if (strrchr(dev->symlink, '/'))
+                       create_path(filename);
+
+               /* optimize relative link */
+               linktarget[0] = '\0';
+               i = 0;
+               tail = 0;
+               while ((dev->name[i] == dev->symlink[i]) && dev->name[i]) {
+                       if (dev->name[i] == '/')
+                               tail = i+1;
+                       i++;
+               }
+               while (dev->symlink[i]) {
+                       if (dev->symlink[i] == '/')
+                               strcat(linktarget, "../");
+                       i++;
+               }
+
+               if (*linktarget == '\0')
+                       strcpy(linktarget, "./");
+               strcat(linktarget, &dev->name[tail]);
+
+               dbg("symlink(%s, %s)", linktarget, filename);
+               retval = symlink(linktarget, filename);
+               if (retval)
+                       dbg("symlink(%s, %s) failed with error '%s'",
+                           linktarget, filename, strerror(errno));
        }
 
        return retval;