* win32/win32.c (rb_w32_seekdir): should not segfault even if passed

  the location which rb_w32_telldir didn't return. [ruby-core:7035]

* test/ruby/test_dir.rb: added.


git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_8@9787 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 33 insertions, 12 deletions

diff --git a/win32/win32.c b/win32/win32.c
index 6541c3dc5b..ef6886af2b 100644
--- a/win32/win32.c
+++ b/win32/win32.c
@@ -1448,6 +1448,20 @@ rb_w32_opendir(const char *filename)
     return p;
 }
 
+//
+// Move to next entry
+//
+
+static void
+move_to_next_entry(DIR *dirp)
+{
+    if (dirp->curr) {
+	dirp->curr += strlen(dirp->curr) + 1;
+	if (dirp->curr >= (dirp->start + dirp->size)) {
+	    dirp->curr = NULL;
+	}
+    }
+}
 
 //
 // Readdir just returns the current string pointer and bumps the
@@ -1457,7 +1471,6 @@ rb_w32_opendir(const char *filename)
 struct direct  *
 rb_w32_readdir(DIR *dirp)
 {
-    int         len;
     static int  dummy = 0;
 
     if (dirp->curr) {
@@ -1466,9 +1479,8 @@ rb_w32_readdir(DIR *dirp)
 	// first set up the structure to return
 	//
 
-	len = strlen(dirp->curr);
 	strcpy(dirp->dirstr.d_name, dirp->curr);
-	dirp->dirstr.d_namlen = len;
+	dirp->dirstr.d_namlen = strlen(dirp->curr);
 
 	//
 	// Fake inode
@@ -1479,10 +1491,7 @@ rb_w32_readdir(DIR *dirp)
 	// Now set up for the next call to readdir
 	//
 
-	dirp->curr += len + 1;
-	if (dirp->curr >= (dirp->start + dirp->size)) {
-	    dirp->curr = NULL;
-	}
+	move_to_next_entry(dirp);
 
 	return &(dirp->dirstr);
 
@@ -1497,7 +1506,15 @@ rb_w32_readdir(DIR *dirp)
 long
 rb_w32_telldir(DIR *dirp)
 {
-	return (long) dirp->curr;	/* ouch! pointer to long cast */
+    long loc = 0; char *p = dirp->curr;
+
+    rb_w32_rewinddir(dirp);
+
+    while (p != dirp->curr) {
+	move_to_next_entry(dirp); loc++;
+    }
+
+    return loc;
 }
 
 //
@@ -1507,7 +1524,11 @@ rb_w32_telldir(DIR *dirp)
 void
 rb_w32_seekdir(DIR *dirp, long loc)
 {
-	dirp->curr = (char *) loc;	/* ouch! long to pointer cast */
+    rb_w32_rewinddir(dirp);
+
+    while (dirp->curr && loc-- > 0) {
+	move_to_next_entry(dirp);
+    }
 }
 
 //
@@ -1517,7 +1538,7 @@ rb_w32_seekdir(DIR *dirp, long loc)
 void
 rb_w32_rewinddir(DIR *dirp)
 {
-	dirp->curr = dirp->start;
+    dirp->curr = dirp->start;
 }
 
 //
@@ -1527,8 +1548,8 @@ rb_w32_rewinddir(DIR *dirp)
 void
 rb_w32_closedir(DIR *dirp)
 {
-	free(dirp->start);
-	free(dirp);
+    free(dirp->start);
+    free(dirp);
 }
 
 EXTERN_C void __cdecl _lock_fhandle(int);