xnu-2782.40.9.tar.gz

[apple/xnu.git] / bsd / hfs / rangelist.c

diff --git a/bsd/hfs/rangelist.c b/bsd/hfs/rangelist.c
index 74ced2e58b115e898c1efc3aca82143fea4b6586..0a1b412b6b7223ec88d769463aa2fb161941b644 100644 (file)
--- a/bsd/hfs/rangelist.c
+++ b/bsd/hfs/rangelist.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2001, 2006-2008 Apple Inc. All rights reserved.
+ * Copyright (c) 2001-2014 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * 
@@ -97,20 +97,18 @@ rl_add(off_t start, off_t end, struct rl_head *rangelist)
        switch (ovcase) {
                case RL_NOOVERLAP: /* 0: no overlap */
                        /*
-                               * If the list was empty 'prev' is undisturbed and 'overlap' == NULL;
-                               * if the search hit a non-overlapping entry PAST the start of the
-                               * new range, 'prev' points to ITS predecessor, and 'overlap' points
-                               * to that entry:
-                               */
+                        * overlap points to the entry we should insert before, or
+                        * if NULL, we should insert at the end.
+                        */
                        MALLOC(range, struct rl_entry *, sizeof(*range), M_TEMP, M_WAITOK);
                        range->rl_start = start;
                        range->rl_end = end;
                        
                        /* Link in the new range: */
                        if (overlap) {
-                               TAILQ_INSERT_AFTER(rangelist, overlap, range, rl_link);
+                               TAILQ_INSERT_BEFORE(overlap, range, rl_link);
                        } else {
-                               TAILQ_INSERT_HEAD(rangelist, range, rl_link);
+                               TAILQ_INSERT_TAIL(rangelist, range, rl_link);
                        }
                        
                        /* Check to see if any ranges can be combined (possibly including the immediately
@@ -314,13 +312,12 @@ rl_scan_from(struct rl_head *rangelist,
                                return RL_NOOVERLAP;
                        };
                        
-                       range = TAILQ_NEXT(range, rl_link);
                        /* Check the other entries in the list: */
-                       if (range == NULL) {
+                       range = TAILQ_NEXT(range, rl_link);
+                       *overlap = range;
+                       if (range == NULL)
                                return RL_NOOVERLAP;
-                       }
                        
-                       *overlap = range;
                        continue;
                }
                
@@ -361,8 +358,6 @@ rl_scan_from(struct rl_head *rangelist,
                panic("hfs: rl_scan_from: unhandled overlap condition?!");
 #endif
        }
-        
-       return RL_NOOVERLAP;
 }
 
 
@@ -418,6 +413,14 @@ rl_collapse_neighbors(struct rl_head *rangelist, struct rl_entry *range)
     rl_collapse_backwards(rangelist, range);
 }
 
+void rl_remove_all(struct rl_head *rangelist)
+{
+       struct rl_entry *r, *nextr;
+       TAILQ_FOREACH_SAFE(r, rangelist, rl_link, nextr)
+               FREE(r, M_TEMP);
+       TAILQ_INIT(rangelist);
+}
+
 #else /* not HFS - temp workaround until 4277828 is fixed */
 /* stubs for exported routines that aren't present when we build kernel without HFS */
 
@@ -448,4 +451,8 @@ int rl_scan(__unused void *rangelist, __unused off_t start, __unused off_t end,
        return(0);
 }
 
+void rl_remove_all(struct rl_head *rangelist)
+{
+}
+
 #endif /* HFS */