From: Jim Meyering <jim@meyering.net>
Date: Mon, 22 Nov 1999 09:07:58 +0000 (+0000)
Subject: (recheck): Handle a race condition (including <dev,inode>
X-Git-Tag: FILEUTILS-4_0j~20
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=7eba3be3400fde5668a8a69d7a0d1d6a352651c5;p=platform%2Fupstream%2Fcoreutils.git

(recheck): Handle a race condition (including <dev,inode>
reuse) that would lead to a failed assertion.
Reported by Ken Pizzini.
(tail_forever): Record errno before using it in call to `error'
which might change it.
(tail_file): Likewise.
---

diff --git a/src/tail.c b/src/tail.c
index 8179f5c..7a2c325 100644
--- a/src/tail.c
+++ b/src/tail.c
@@ -789,7 +789,17 @@ recheck (struct File_spec *f)
     }
   else
     {
-      close_fd (fd, pretty_name (f));
+      if (f->fd == -1)
+	{
+	  /* This happens when one iteration finds the file missing,
+	     then the preceding <dev,inode> pair is reused as the
+	     file is recreated.  */
+	  new_file = 1;
+	}
+      else
+	{
+	  close_fd (fd, pretty_name (f));
+	}
     }
 
   if (new_file)
@@ -855,9 +865,9 @@ tail_forever (struct File_spec *f, int nfiles)
 
 	  if (fstat (f[i].fd, &stats) < 0)
 	    {
-	      error (0, errno, "%s", pretty_name (&f[i]));
 	      f[i].fd = -1;
 	      f[i].errnum = errno;
+	      error (0, errno, "%s", pretty_name (&f[i]));
 	      continue;
 	    }
 
@@ -1119,9 +1129,9 @@ tail_file (struct File_spec *f, off_t n_units)
 	  /* FIXME: duplicate code */
 	  if (fstat (fd, &stats) < 0)
 	    {
-	      error (0, errno, "%s", pretty_name (f));
 	      errors = 1;
 	      f->errnum = errno;
+	      error (0, errno, "%s", pretty_name (f));
 	    }
 
 	  if (errors)