update all NEED_ROOT uses

[libguestfs.git] / daemon / headtail.c

diff --git a/daemon/headtail.c b/daemon/headtail.c
index 6d24851..79dcfbb 100644 (file)
--- a/daemon/headtail.c
+++ b/daemon/headtail.c
@@ -32,20 +32,18 @@ headtail (const char *prog, const char *flag, const char *n, char *path)
 {
   char *buf;
   char *out, *err;
-  int r, len;
+  int r;
   char **lines;
 
-  NEED_ROOT (NULL);
-  ABS_PATH (path, NULL);
+  NEED_ROOT (return NULL);
+  ABS_PATH (path, return NULL);
 
   /* Make the path relative to /sysroot. */
-  len = strlen (path) + 9;
-  buf = malloc (len);
+  buf = sysroot_path (path);
   if (!buf) {
     reply_with_perror ("malloc");
     return NULL;
   }
-  snprintf (buf, len, "/sysroot%s", path);
 
   r = command (&out, &err, prog, flag, n, buf, NULL);
   free (buf);