(fix) luidgen needs lib/luid.h

src/lib/luid.c

@@ -0,0 +1,113 @@
+/*
+  luid  -  Lumiera unique identifiers
+
+  Copyright (C)         Lumiera.org
+    2008,               Christian Thaeter <ct@pipapo.org>
+
+  This program is free software; you can redistribute it and/or
+  modify it under the terms of the GNU General Public License as
+  published by the Free Software Foundation; either version 2 of the
+  License, or (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+#include "lib/luid.h"
+
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <time.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <string.h>
+#include <stdint.h>
+
+void
+lumiera_uid_set_ptr (lumiera_uid* luid, void* ptr)
+{
+  memset (luid, 0, 16);
+  *(void**)luid = ptr;
+}
+
+
+void*
+lumiera_uid_ptr_get (lumiera_uid* luid)
+{
+  return *(void**)luid;
+}
+
+
+void
+lumiera_uid_gen (lumiera_uid* luid)
+{
+  static int fd = -2;
+  if (!luid)
+    return;
+
+  if (fd == -2)
+    {
+      fd = open ("/dev/urandom", O_RDONLY);
+      /* on linux /dev/random would be way to slow for our purpose, so we comment that out for now.
+         other unixiods offer a /dev/random which has the same semantics as linux /dev/urandom has,
+         configuration should do this right some day.
+      if (fd == -1)
+        fd = open ("/dev/random", O_RDONLY);
+      */
+      if (fd >= 0)
+        fcntl (fd, F_SETFD, FD_CLOEXEC);
+      else
+        srand (getpid () + time (NULL));
+    }
+
+  do
+    {
+      if (fd < 0)
+        {
+          for (int i = 0; i < 16; ++i)
+            ((unsigned char*)luid)[i] = (unsigned char)(rand()>>7);
+        }
+      else
+        {
+          if (read (fd, luid, 16) < 16)
+            abort ();
+        }
+    }
+  /* we identify generic pointers by having some zeros in the luid,
+   * this happens very unlikely to be in a random luid, just regenerate it then */
+  while (!*(((intptr_t*)luid)+1));
+}
+
+
+void
+lumiera_uid_copy (lumiera_uid* dest, lumiera_uid* src)
+{
+  memcpy (dest, src, 16);
+}
+
+
+int
+lumiera_uid_eq (lumiera_uid* luida, lumiera_uid* luidb)
+{
+  return !memcmp (luida, luidb, 16);
+}
+
+size_t
+lumiera_uid_hash (lumiera_uid* luid)
+{
+  return *(size_t*)luid;
+}
+
+/*
+// Local Variables:
+// mode: C
+// c-file-style: "gnu"
+// indent-tabs-mode: nil
+// End:
+*/

src/lib/luid.h

@@ -0,0 +1,97 @@
+/*
+  luid  -  Lumiera unique identifiers
+
+  Copyright (C)         Lumiera.org
+    2008,               Christian Thaeter <ct@pipapo.org>
+
+  This program is free software; you can redistribute it and/or
+  modify it under the terms of the GNU General Public License as
+  published by the Free Software Foundation; either version 2 of the
+  License, or (at your option) any later version.
+
+  This program is distributed in the hope that it will be useful,
+  but WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+  GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License
+  along with this program; if not, write to the Free Software
+  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+#ifndef LUMIERA_LUID_H
+#define LUMIERA_LUID_H
+
+#include <stdlib.h>
+
+/**
+ * @file
+ * Lumiera unique identifiers are 128 byte random value. Unlike standard uuid's we
+ * don't tag a version within them and we may store generic pointers in the space
+ * occupied by an luid.
+ */
+
+typedef unsigned char lumiera_uid[16];
+typedef lumiera_uid* LumieraUid;
+
+/*
+ C++ can't initialize arrays from string literals with the trailing \0 cropped
+ C can't initialize non constant members,
+ there we go
+*/
+#ifdef __cplusplus
+#define LUMIERA_UID_INITIALIZER(l)                              \
+  {                                                             \
+    l[0], l[1], l[2], l[3], l[4], l[5], l[6], l[7],             \
+    l[8], l[9], l[10], l[11], l[12], l[13], l[14], l[15]        \
+  }
+#else
+#define LUMIERA_UID_INITIALIZER(l) l
+#endif
+
+/**
+ * Retrieve a generic pointer stored in a luid
+ */
+void*
+lumiera_uid_ptr_get (lumiera_uid* luid);
+
+/**
+ * Generate a new luid
+ */
+void
+lumiera_uid_gen (lumiera_uid* luid);
+
+/**
+ * Store a generic pointer in a luid
+ */
+void
+lumiera_uid_set_ptr (lumiera_uid* luid, void* ptr);
+
+
+/**
+ * Copy an luid
+ */
+void
+lumiera_uid_copy (lumiera_uid* dest, lumiera_uid* src);
+
+
+/**
+ * Test 2 luid's for equality
+ */
+int
+lumiera_uid_eq (lumiera_uid* luida, lumiera_uid* luidb);
+
+
+/**
+ * Generate a hashsum over an luid
+ */
+size_t
+lumiera_uid_hash (lumiera_uid* luid);
+
+#endif
+/*
+// Local Variables:
+// mode: C
+// c-file-style: "gnu"
+// indent-tabs-mode: nil
+// End:
+*/