--- libeio/eio.c	2011/12/30 07:38:00	1.114
+++ libeio/eio.c	2012/04/24 18:47:50	1.120
@@ -1,7 +1,7 @@
 /*
  * libeio implementation
  *
- * Copyright (c) 2007,2008,2009,2010,2011 Marc Alexander Lehmann <libeio@schmorp.de>
+ * Copyright (c) 2007,2008,2009,2010,2011,2012 Marc Alexander Lehmann <libeio@schmorp.de>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without modifica-
@@ -210,7 +210,7 @@
   #define D_NAME(entp) entp->d_name
 
   /* POSIX_SOURCE is useless on bsd's, and XOPEN_SOURCE is unreliable there, too */
-  #if __FreeBSD__ || defined __NetBSD__ || defined __OpenBSD__
+  #if __FreeBSD__ || __NetBSD__ || __OpenBSD__
     #define _DIRENT_HAVE_D_TYPE /* sigh */
     #define D_INO(de) (de)->d_fileno
     #define D_NAMLEN(de) (de)->d_namlen
@@ -1034,8 +1034,7 @@
 #if HAVE_SYS_SYNCFS
   res = (int)syscall (__NR_syncfs, (int)(fd));
 #else
-  res = -1;
-  errno = ENOSYS;
+  res = EIO_ENOSYS ();
 #endif
 
   if (res < 0 && errno == ENOSYS && fd >= 0)
@@ -1075,11 +1074,10 @@
 static int
 eio__fallocate (int fd, int mode, off_t offset, size_t len)
 {
-#if HAVE_FALLOCATE
+#if HAVE_LINUX_FALLOCATE
   return fallocate (fd, mode, offset, len);
 #else
-  errno = ENOSYS;
-  return -1;
+  return EIO_ENOSYS ();
 #endif
 }
 
@@ -1104,8 +1102,9 @@
 
   FUBd;
 
-  errno = 0;
-  return count;
+  /* linux's readahead basically only fails for EBADF or EINVAL (not mmappable) */
+  /* but not for e.g. EIO or eof, so we also never fail */
+  return 0;
 }
 
 #endif
@@ -1150,7 +1149,7 @@
       if (sbytes)
         res = sbytes;
 
-# elif defined (__APPLE__)
+# elif defined __APPLE__
       off_t sbytes = count;
       res = sendfile (ifd, ofd, offset, &sbytes, 0, 0);
 
@@ -1187,8 +1186,7 @@
       res = TransmitFile (TO_SOCKET (ofd), h, count, 0, 0, 0, 0);
 
 #else
-      res = -1;
-      errno = ENOSYS;
+      res = EIO_ENOSYS ();
 #endif
 
       /* we assume sendfile can copy at least 128mb in one go */
@@ -1384,6 +1382,20 @@
 /*****************************************************************************/
 /* requests implemented outside eio_execute, because they are so large */
 
+static void
+eio__lseek (eio_req *req)
+{
+  /* this usually gets optimised away completely, or your compiler sucks, */
+  /* or the whence constants really are not 0, 1, 2 */
+  int whence = req->int2 == EIO_SEEK_SET ? SEEK_SET
+             : req->int2 == EIO_SEEK_CUR ? SEEK_CUR
+             : req->int2 == EIO_SEEK_END ? SEEK_END
+             : req->int2;
+
+  req->offs   = lseek (req->int1, req->offs, whence);
+  req->result = req->offs == (off_t)-1 ? -1 : 0;
+}
+
 /* result will always end up in tmpbuf, there is always space for adding a 0-byte */
 static int
 eio__realpath (struct tmpbuf *tmpbuf, eio_wd wd, const char *path)
@@ -2230,8 +2242,6 @@
   X_LOCK (wrklock);
   etp_worker_free (self);
   X_UNLOCK (wrklock);
-
-  return 0;
 }
 
 /*****************************************************************************/
@@ -2316,6 +2326,7 @@
       case EIO_WD_CLOSE:  req->result = 0;
                           eio_wd_close_sync (req->wd); break;
 
+      case EIO_SEEK:      eio__lseek (req); break;
       case EIO_READ:      ALLOC (req->size);
                           req->result = req->offs >= 0
                                       ? pread     (req->int1, req->ptr2, req->size, req->offs)
@@ -2481,8 +2492,7 @@
         break;
 
       default:
-        errno = ENOSYS;
-        req->result = -1;
+        req->result = EIO_ENOSYS ();
         break;
     }
 
@@ -2571,6 +2581,11 @@
   REQ (EIO_READAHEAD); req->int1 = fd; req->offs = offset; req->size = length; SEND;
 }
 
+eio_req *eio_seek (int fd, off_t offset, int whence, int pri, eio_cb cb, void *data)
+{
+  REQ (EIO_SEEK); req->int1 = fd; req->offs = offset; req->int2 = whence; SEND;
+}
+
 eio_req *eio_read (int fd, void *buf, size_t length, off_t offset, int pri, eio_cb cb, void *data)
 {
   REQ (EIO_READ); req->int1 = fd; req->offs = offset; req->size = length; req->ptr2 = buf; SEND;