svn commit: r196695 - stable/8/usr.bin/look

[Colin Percival]

Author: cperciva
Date: Mon Aug 31 13:02:21 2009
New Revision: 196695
URL: http://svn.freebsd.org/changeset/base/196695

Log:
  MFC r196558: Don't try to mmap the contents of empty files.  This behaviour
  was harmless prior to r195693, when mmap(2) changed from silently ignoring
  requests for mapping zero bytes to returning EINVAL; this commit can be seen
  as adjusting for the change in mmap(2) in order to make look(1) act like it
  did previously.
  
  Reviewed by:	jhb
  Approved by:	re (kib)

Modified:
  stable/8/usr.bin/look/   (props changed)
  stable/8/usr.bin/look/look.c

Modified: stable/8/usr.bin/look/look.c
==============================================================================
--- stable/8/usr.bin/look/look.c	Mon Aug 31 12:25:04 2009	(r196694)
+++ stable/8/usr.bin/look/look.c	Mon Aug 31 13:02:21 2009	(r196695)
@@ -140,6 +140,10 @@ main(int argc, char *argv[])
 			err(2, "%s", file);
 		if (sb.st_size > SIZE_T_MAX)
 			errx(2, "%s: %s", file, strerror(EFBIG));
+		if (sb.st_size == 0) {
+			close(fd);
+			continue;
+		}
 		if ((front = mmap(NULL, (size_t)sb.st_size, PROT_READ, MAP_SHARED, fd, (off_t)0)) == MAP_FAILED)
 			err(2, "%s", file);
 		back = front + sb.st_size;