add files for 2006-08-31T01:36:25Z

diff --git a/src/osdep/unix/crx_nfs.c b/src/osdep/unix/crx_nfs.c
new file mode 100644 (file)
index 0000000..7e60e63
--- /dev/null
+++ b/src/osdep/unix/crx_nfs.c
@@ -0,0 +1,79 @@
+/* ========================================================================
+ * Copyright 1988-2006 University of Washington
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * 
+ * ========================================================================
+ */
+
+/*
+ * Program:    Exclusive create of a file, NFS kludge version
+ *
+ * Author:     Mark Crispin
+ *             Networks and Distributed Computing
+ *             Computing & Communications
+ *             University of Washington
+ *             Administration Building, AG-44
+ *             Seattle, WA  98195
+ *             Internet: MRC@CAC.Washington.EDU
+ *
+ * Date:       17 December 1999
+ * Last Edited:        30 August 2006
+ */
+
+
+/* SUN-OS had an NFS, As kludgy as an albatross;
+ * And everywhere that it was installed, It was a total loss.
+ *  -- MRC 9/25/91
+ */
+\f
+/* Exclusive create of a file
+ * Accepts: file name
+ * Return: T if success, NIL if failed, -1 if retry
+ */
+
+long crexcl (char *name)
+{
+  long ret = -1;
+  int i;
+  char hitch[MAILTMPLEN];
+  struct stat sb;
+  int mask = umask (0);
+                               /* build hitching post file name */
+  sprintf (hitch,"%s.%lu.%d.",name,(unsigned long) time (0),getpid ());
+  i = strlen (hitch);          /* append local host name */
+  gethostname (hitch + i,(MAILTMPLEN - i) - 1);
+                               /* try to get hitching-post file */
+  if ((i = open (hitch,O_WRONLY|O_CREAT|O_EXCL,(int) shlock_mode)) >= 0) {
+    close (i);                 /* close the hitching-post */
+    /* Note: link() may return an error even if it actually succeeded.  So we
+     * always check for success via the link count, and ignore the error if
+     * the link count is right.
+     */
+                               /* tie hitching-post to lock */
+    i = link (hitch,name) ? errno : 0;
+                               /* success if link count now 2 */
+    if (!stat (hitch,&sb) && (sb.st_nlink == 2)) ret = LONGT;
+    else if (i == EPERM) {     /* links not allowed? */
+      /* Probably a FAT filesystem on Linux.  It can't be NFS, so try creating
+       * the lock file directly.
+       */
+      if ((i = open (name,O_WRONLY|O_CREAT|O_EXCL,(int) shlock_mode)) >= 0){
+       close (i);              /* close the file */
+       ret = LONGT;            /* success */
+      }
+                               /* fail unless error is EEXIST */
+      else if (errno != EEXIST) ret = NIL;
+    }
+    unlink (hitch);            /* flush hitching post */
+  }
+                               /* fail unless error is EEXIST */
+  else if (errno != EEXIST) ret = NIL;
+  umask (mask);                        /* restore previous mask */
+  return ret;
+}