(main): Check for incompatible options. -R --dereference

requires either -H or -L, and -R -h requires -P.  If -H, specify
FTS_PHYSICAL as well as FTS_COMFOLLOW; this is faster.  Make this
file as much like chgrp.c as possible.

1 files changed, 29 insertions, 3 deletions

diff --git a/src/chown.c b/src/chown.c
index 7975904b9..8a943604e 100644
--- a/src/chown.c
+++ b/src/chown.c
@@ -170,6 +170,10 @@ main (int argc, char **argv)
   /* Bit flags that control how fts works.  */
   int bit_flags = FTS_PHYSICAL;
 
+  /* 1 if --dereference, 0 if --no-dereference, -1 if neither has been
+     specified.  */
+  int dereference = -1;
+
   struct Chown_option chopt;
   int fail;
   int optc;
@@ -193,7 +197,7 @@ main (int argc, char **argv)
 	  break;
 
 	case 'H': /* Traverse command-line symlinks-to-directories.  */
-	  bit_flags = FTS_COMFOLLOW;
+	  bit_flags = FTS_COMFOLLOW | FTS_PHYSICAL;
 	  break;
 
 	case 'L': /* Traverse all symlinks-to-directories.  */
@@ -205,12 +209,12 @@ main (int argc, char **argv)
 	  break;
 
 	case 'h': /* --no-dereference: affect symlinks */
-	  chopt.affect_symlink_referent = false;
+	  dereference = 0;
 	  break;
 
 	case DEREFERENCE_OPTION: /* --dereference: affect the referent
 				    of each symlink */
-	  chopt.affect_symlink_referent = true;
+	  dereference = 1;
 	  break;
 
 	case NO_PRESERVE_ROOT:
@@ -259,6 +263,28 @@ main (int argc, char **argv)
 	}
     }
 
+  if (chopt.recurse)
+    {
+      if (bit_flags == FTS_PHYSICAL)
+	{
+	  if (dereference == 1)
+	    error (EXIT_FAILURE, 0,
+		   _("-R --dereference requires either -H or -L"));
+	  chopt.affect_symlink_referent = false;
+	}
+      else
+	{
+	  if (dereference == 0)
+	    error (EXIT_FAILURE, 0, _("-R -h requires -P"));
+	  chopt.affect_symlink_referent = true;
+	}
+    }
+  else
+    {
+      bit_flags = FTS_PHYSICAL;
+      chopt.affect_symlink_referent = (dereference != 0);
+    }
+
   if (argc - optind + (reference_file ? 1 : 0) <= 1)
     {
       error (0, 0, _("too few arguments"));