Include hash.h and cycle-check.h.

(FTS_TIGHT_CYCLE_CHECK): New value.
(FTS_OPTIONMASK): Adjust to include the new value.
(FTS_NAMEONLY, FTS_STOP): Increase to allow room for new value.
(struct FTS) [active_dir_ht]: New member.  Replaces fts_dir_signatures.
(struct FTS) [cycle_state]: New member.

diff --git a/lib/fts_.h b/lib/fts_.h
index a0ceaf6299fac61279f264ce39982ef646beec94..496211f6ee5117025b7e5df284706e26031bf639 100644 (file)
--- a/lib/fts_.h
+++ b/lib/fts_.h
@@ -44,6 +44,8 @@
 # endif
 
 # include <sys/types.h>
+# include "hash.h"
+# include "cycle-check.h"
 
 typedef struct {
        struct _ftsent *fts_cur;        /* current node */
@@ -64,10 +66,23 @@ typedef struct {
 # define FTS_SEEDOT    0x0020          /* return dot and dot-dot */
 # define FTS_XDEV      0x0040          /* don't cross devices */
 # define FTS_WHITEOUT  0x0080          /* return whiteout information */
-# define FTS_OPTIONMASK        0x00ff          /* valid user option mask */
 
-# define FTS_NAMEONLY  0x0100          /* (private) child names only */
-# define FTS_STOP      0x0200          /* (private) unrecoverable error */
+  /* There are two ways to detect cycles.
+     The lazy way, with which one may process a directory that is a
+     part of the cycle several times before detecting the cycle.
+     The `tight' way, whereby fts uses more memory (proportional
+     to number of `active' directories, aka distance from root
+     of current tree to current directory -- see active_dir_ht)
+     to detect any cycle right away.  For example, du must use
+     this option to avoid counting disk space in a cycle multiple
+     times, but chown -R need not.
+     The default is to use the constant-memory lazy way. */
+# define FTS_TIGHT_CYCLE_CHECK 0x0100
+
+# define FTS_OPTIONMASK        0x01ff          /* valid user option mask */
+
+# define FTS_NAMEONLY  0x1000          /* (private) child names only */
+# define FTS_STOP      0x2000          /* (private) unrecoverable error */
        int fts_options;                /* fts_open options, global flags */
 
        /* This data structure records the directories between a starting
@@ -80,10 +95,9 @@ typedef struct {
           This data structure is used to detect directory cycles efficiently
           and promptly even when the depth of a hierarchy is in the tens
           of thousands.  Lazy checking, as done by GNU rm via cycle-check.c,
-          wouldn't be appropriate for du.
-          FIXME: add an option so that we *do* use cycle-check.c, except
-          when necessary.  */
-       void *fts_dir_signatures;
+          wouldn't be appropriate for du.  */
+       Hash_table *active_dir_ht;
+       struct cycle_check_state *cycle_state;
 } FTS;
 
 typedef struct _ftsent {