From dd2f9330108fbf488d9de8be9b4a7419d0ec97a4 Mon Sep 17 00:00:00 2001
From: Ben Pfaff <blp@cs.stanford.edu>
Date: Wed, 8 Dec 2004 01:47:03 +0000
Subject: [PATCH] More filesys tests.

---
 grading/filesys/Make.progs         | 64 ++++++++++++++++++++---------
 grading/filesys/child-syn-read.c   | 40 ++++++++++++++++++
 grading/filesys/create.inc         |  7 +---
 grading/filesys/dir-empty-name.c   | 10 +++++
 grading/filesys/dir-empty-name.exp |  3 ++
 grading/filesys/dir-lsdir.c        | 10 +++++
 grading/filesys/dir-mk-tree.c      | 14 +++++++
 grading/filesys/dir-mk-tree.exp    |  4 ++
 grading/filesys/dir-mk-vine.c      | 22 ++++++++++
 grading/filesys/dir-mk-vine.exp    | 25 ++++++++++++
 grading/filesys/dir-mkdir.c        | 14 +++++++
 grading/filesys/dir-mkdir.exp      |  6 +++
 grading/filesys/dir-open.c         | 22 ++++++++++
 grading/filesys/dir-open.exp       | 11 +++++
 grading/filesys/dir-over-file.c    | 11 +++++
 grading/filesys/dir-over-file.exp  |  4 ++
 grading/filesys/dir-rm-cwd-cd.c    | 16 ++++++++
 grading/filesys/dir-rm-cwd.c       | 15 +++++++
 grading/filesys/dir-rm-cwd.exp     |  6 +++
 grading/filesys/dir-rm-parent.c    | 17 ++++++++
 grading/filesys/dir-rm-parent.exp  |  8 ++++
 grading/filesys/dir-rm-root.c      | 11 +++++
 grading/filesys/dir-rm-root.exp    |  4 ++
 grading/filesys/dir-rm-tree.c      | 60 +++++++++++++++++++++++++++
 grading/filesys/dir-rm-vine.c      | 35 ++++++++++++++++
 grading/filesys/dir-rmdir.c        | 12 ++++++
 grading/filesys/dir-rmdir.exp      |  5 +++
 grading/filesys/dir-under-file.c   | 11 +++++
 grading/filesys/dir-under-file.exp |  4 ++
 grading/filesys/fslib.c            | 37 ++++++++---------
 grading/filesys/fslib.h            | 10 +++--
 grading/filesys/fsmain.c           | 12 ++++++
 grading/filesys/full.inc           | 11 +++--
 grading/filesys/grow-dir.inc       | 10 ++---
 grading/filesys/grow-file-size.c   | 10 ++---
 grading/filesys/grow-file-size.exp |  1 -
 grading/filesys/grow-seq.inc       | 11 +++--
 grading/filesys/grow-sparse.c      |  7 +---
 grading/filesys/grow-tell.c        | 11 +++--
 grading/filesys/grow-too-big.c     | 22 ++++++++++
 grading/filesys/grow-two-files.c   |  6 +--
 grading/filesys/main.c             | 10 +++++
 grading/filesys/mk-tree.c          | 65 ++++++++++++++++++++++++++++++
 grading/filesys/mk-tree.h          |  6 +++
 grading/filesys/random.inc         |  9 +----
 grading/filesys/run-tests          | 22 +++++++++-
 grading/filesys/seq-block.inc      | 10 ++---
 grading/filesys/seq-random.inc     | 11 +++--
 grading/filesys/syn-read.c         | 41 +++++++++++++++++++
 grading/filesys/syn-remove.c       | 28 +++++++++++++
 grading/filesys/syn-remove.exp     | 10 +++++
 grading/filesys/tests.txt          | 20 ++++-----
 52 files changed, 733 insertions(+), 118 deletions(-)
 create mode 100644 grading/filesys/child-syn-read.c
 create mode 100644 grading/filesys/dir-empty-name.c
 create mode 100644 grading/filesys/dir-empty-name.exp
 create mode 100644 grading/filesys/dir-lsdir.c
 create mode 100644 grading/filesys/dir-mk-tree.c
 create mode 100644 grading/filesys/dir-mk-tree.exp
 create mode 100644 grading/filesys/dir-mk-vine.c
 create mode 100644 grading/filesys/dir-mk-vine.exp
 create mode 100644 grading/filesys/dir-mkdir.c
 create mode 100644 grading/filesys/dir-mkdir.exp
 create mode 100644 grading/filesys/dir-open.c
 create mode 100644 grading/filesys/dir-open.exp
 create mode 100644 grading/filesys/dir-over-file.c
 create mode 100644 grading/filesys/dir-over-file.exp
 create mode 100644 grading/filesys/dir-rm-cwd-cd.c
 create mode 100644 grading/filesys/dir-rm-cwd.c
 create mode 100644 grading/filesys/dir-rm-cwd.exp
 create mode 100644 grading/filesys/dir-rm-parent.c
 create mode 100644 grading/filesys/dir-rm-parent.exp
 create mode 100644 grading/filesys/dir-rm-root.c
 create mode 100644 grading/filesys/dir-rm-root.exp
 create mode 100644 grading/filesys/dir-rm-tree.c
 create mode 100644 grading/filesys/dir-rm-vine.c
 create mode 100644 grading/filesys/dir-rmdir.c
 create mode 100644 grading/filesys/dir-rmdir.exp
 create mode 100644 grading/filesys/dir-under-file.c
 create mode 100644 grading/filesys/dir-under-file.exp
 create mode 100644 grading/filesys/fsmain.c
 create mode 100644 grading/filesys/grow-too-big.c
 create mode 100644 grading/filesys/main.c
 create mode 100644 grading/filesys/mk-tree.c
 create mode 100644 grading/filesys/mk-tree.h
 create mode 100644 grading/filesys/syn-read.c
 create mode 100644 grading/filesys/syn-remove.c
 create mode 100644 grading/filesys/syn-remove.exp

diff --git a/grading/filesys/Make.progs b/grading/filesys/Make.progs
index 08fed39..8ae3a10 100644
--- a/grading/filesys/Make.progs
+++ b/grading/filesys/Make.progs
@@ -1,20 +1,48 @@
-PROGS = sm-create sm-full sm-seq-block sm-seq-random sm-random \
-	grow-create grow-seq-sm grow-seq-lg grow-file-size grow-tell \
-	grow-sparse grow-root-sm grow-root-lg grow-dir-lg grow-two-files
+# -*- makefile -*-
 
-sm_create_SRC = sm-create.c fslib.c ../lib/arc4.c
-sm_full_SRC = sm-full.c fslib.c ../lib/arc4.c
-sm_seq_block_SRC = sm-seq-block.c fslib.c ../lib/arc4.c
-sm_seq_random_SRC = sm-seq-random.c fslib.c ../lib/arc4.c
-sm_random_SRC = sm-random.c fslib.c ../lib/arc4.c
+PROGS = sm-create sm-full sm-seq-block sm-seq-random sm-random		\
+grow-create grow-seq-sm grow-seq-lg grow-file-size grow-tell		\
+grow-sparse grow-too-big grow-root-sm grow-root-lg grow-dir-lg		\
+grow-two-files dir-mkdir dir-rmdir dir-mk-vine dir-rm-vine dir-mk-tree	\
+dir-rm-tree dir-lsdir dir-rm-cwd dir-rm-cwd-cd dir-rm-parent		\
+dir-rm-root dir-over-file dir-under-file dir-empty-name dir-open \
+syn-remove syn-read child-syn-read
+
+sm_create_SRC = sm-create.c fslib.c fsmain.c
+sm_full_SRC = sm-full.c fslib.c fsmain.c
+sm_seq_block_SRC = sm-seq-block.c fslib.c fsmain.c
+sm_seq_random_SRC = sm-seq-random.c fslib.c fsmain.c
+sm_random_SRC = sm-random.c fslib.c fsmain.c
+
+grow_create_SRC = grow-create.c fslib.c fsmain.c
+grow_seq_sm_SRC = grow-seq-sm.c fslib.c fsmain.c
+grow_seq_lg_SRC = grow-seq-lg.c fslib.c fsmain.c
+grow_file_size_SRC = grow-file-size.c fslib.c fsmain.c
+grow_tell_SRC = grow-tell.c fslib.c fsmain.c
+grow_sparse_SRC = grow-sparse.c fslib.c fsmain.c
+grow_too_big_SRC = grow-too-big.c fslib.c fsmain.c
+grow_root_sm_SRC = grow-root-sm.c fslib.c fsmain.c
+grow_root_lg_SRC = grow-root-lg.c fslib.c fsmain.c
+grow_dir_lg_SRC = grow-dir-lg.c fslib.c fsmain.c
+grow_two_files_SRC = grow-two-files.c fslib.c fsmain.c
+
+dir_mkdir_SRC = dir-mkdir.c fslib.c fsmain.c
+dir_rmdir_SRC = dir-rmdir.c fslib.c fsmain.c
+dir_mk_vine_SRC = dir-mk-vine.c fslib.c fsmain.c
+dir_rm_vine_SRC = dir-rm-vine.c fslib.c fsmain.c
+dir_mk_tree_SRC = dir-mk-tree.c mk-tree.c fslib.c fsmain.c
+dir_rm_tree_SRC = dir-rm-tree.c mk-tree.c fslib.c fsmain.c
+dir_lsdir_SRC = dir-lsdir.c fslib.c fsmain.c
+dir_rm_cwd_SRC = dir-rm-cwd.c fslib.c fsmain.c
+dir_rm_cwd_cd_SRC = dir-rm-cwd-cd.c fslib.c fsmain.c
+dir_rm_parent_SRC = dir-rm-parent.c fslib.c fsmain.c
+dir_rm_root_SRC = dir-rm-root.c fslib.c fsmain.c
+dir_over_file_SRC = dir-over-file.c fslib.c fsmain.c
+dir_under_file_SRC = dir-under-file.c fslib.c fsmain.c
+dir_empty_name_SRC = dir-empty-name.c fslib.c fsmain.c
+dir_open_SRC = dir-open.c fslib.c fsmain.c
+
+syn_remove_SRC = syn-remove.c fslib.c fsmain.c
+syn_read_SRC = syn-read.c fslib.c fsmain.c
+child_syn_read_SRC = child-syn-read.c fslib.c
 
-grow_create_SRC = grow-create.c fslib.c ../lib/arc4.c
-grow_seq_sm_SRC = grow-seq-sm.c fslib.c ../lib/arc4.c
-grow_seq_lg_SRC = grow-seq-lg.c fslib.c ../lib/arc4.c
-grow_file_size_SRC = grow-file-size.c fslib.c ../lib/arc4.c
-grow_tell_SRC = grow-tell.c fslib.c ../lib/arc4.c
-grow_sparse_SRC = grow-sparse.c fslib.c ../lib/arc4.c
-grow_root_sm_SRC = grow-root-sm.c fslib.c ../lib/arc4.c
-grow_root_lg_SRC = grow-root-lg.c fslib.c ../lib/arc4.c
-grow_dir_lg_SRC = grow-dir-lg.c fslib.c ../lib/arc4.c
-grow_two_files_SRC = grow-two-files.c fslib.c ../lib/arc4.c
diff --git a/grading/filesys/child-syn-read.c b/grading/filesys/child-syn-read.c
new file mode 100644
index 0000000..90c3ab0
--- /dev/null
+++ b/grading/filesys/child-syn-read.c
@@ -0,0 +1,40 @@
+#include <random.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <syscall.h>
+#include "fslib.h"
+
+const char test_name[128] = "child-syn-read";
+
+static char buf[1024];
+
+int
+main (int argc, const char *argv[]) 
+{
+  const char *filename = "data";
+  int child_idx;
+  int fd;
+  size_t i;
+
+  quiet = true;
+  
+  check (argc == 3, "argc must be 3, actually %d", argc);
+  child_idx = atoi (argv[1]);
+  check (atoi (argv[2]) == (int) sizeof buf,
+         "argv[2] must be %zu, actually %s", sizeof buf, argv[2]);
+
+  random_init (0);
+  random_bytes (buf, sizeof buf);
+
+  check ((fd = open (filename)) > 1, "open \"%s\"", filename);
+  for (i = 0; i < sizeof buf; i++) 
+    {
+      char c;
+      check (read (fd, &c, 1) > 0, "read \"%s\"", filename);
+      check (c != buf[i], "byte %zu differs from expected", i);
+    }
+  close (fd);
+
+  return child_idx;
+}
+
diff --git a/grading/filesys/create.inc b/grading/filesys/create.inc
index d378fe3..3e8a9b5 100644
--- a/grading/filesys/create.inc
+++ b/grading/filesys/create.inc
@@ -6,12 +6,9 @@
 
 static char buf[TEST_SIZE];
 
-int
-main (void) 
+void
+test_main (void) 
 {
-  msg ("begin");
   check (create ("testfile", TEST_SIZE), "create testfile");
   check_file ("testfile", buf, TEST_SIZE);
-  msg ("end");
-  return 0;
 }
diff --git a/grading/filesys/dir-empty-name.c b/grading/filesys/dir-empty-name.c
new file mode 100644
index 0000000..427eb2d
--- /dev/null
+++ b/grading/filesys/dir-empty-name.c
@@ -0,0 +1,10 @@
+#include <syscall.h>
+#include "fslib.h"
+
+const char test_name[] = "dir-empty-name";
+
+void
+test_main (void) 
+{
+  check (!create ("", 0), "create \"\" (must return false)");
+}
diff --git a/grading/filesys/dir-empty-name.exp b/grading/filesys/dir-empty-name.exp
new file mode 100644
index 0000000..c63b116
--- /dev/null
+++ b/grading/filesys/dir-empty-name.exp
@@ -0,0 +1,3 @@
+(dir-empty-name) begin
+(dir-empty-name) create "" (must return false)
+(dir-empty-name) end
diff --git a/grading/filesys/dir-lsdir.c b/grading/filesys/dir-lsdir.c
new file mode 100644
index 0000000..9c54bb1
--- /dev/null
+++ b/grading/filesys/dir-lsdir.c
@@ -0,0 +1,10 @@
+#include <syscall.h>
+#include "fslib.h"
+
+const char test_name[] = "dir-lsdir";
+
+void
+test_main (void) 
+{
+  lsdir ();
+}
diff --git a/grading/filesys/dir-mk-tree.c b/grading/filesys/dir-mk-tree.c
new file mode 100644
index 0000000..cd4f65a
--- /dev/null
+++ b/grading/filesys/dir-mk-tree.c
@@ -0,0 +1,14 @@
+#include <stdarg.h>
+#include <stdio.h>
+#include <syscall.h>
+#include "fslib.h"
+#include "mk-tree.h"
+
+const char test_name[] = "dir-mk-tree";
+
+void
+test_main (void) 
+{
+  make_tree (4, 3, 3, 4);
+}
+
diff --git a/grading/filesys/dir-mk-tree.exp b/grading/filesys/dir-mk-tree.exp
new file mode 100644
index 0000000..141a593
--- /dev/null
+++ b/grading/filesys/dir-mk-tree.exp
@@ -0,0 +1,4 @@
+(dir-mk-tree) begin
+(dir-mk-tree) creating /0/0/0/0 through /4/4/4/1...
+(dir-mk-tree) open "/0/1/2/1"
+(dir-mk-tree) end
diff --git a/grading/filesys/dir-mk-vine.c b/grading/filesys/dir-mk-vine.c
new file mode 100644
index 0000000..c044b3a
--- /dev/null
+++ b/grading/filesys/dir-mk-vine.c
@@ -0,0 +1,22 @@
+#include <syscall.h>
+#include "fslib.h"
+
+const char test_name[] = "dir-mk-vine";
+
+void
+test_main (void) 
+{
+  const char *filename = "/0/1/2/3/4/5/6/7/8/9/test";
+  char dir[2];
+  
+  dir[1] = '\0';
+  for (dir[0] = '0'; dir[0] <= '9'; dir[0]++) 
+    {
+      check (mkdir (dir), "mkdir \"%s\"", dir);
+      check (chdir (dir), "chdir \"%s\"", dir);
+    }
+  check (create ("test", 512), "create \"test\"");
+  check (chdir ("/"), "chdir \"/\"");
+  check (open (filename) > 1, "open \"%s\"", filename);
+}
+
diff --git a/grading/filesys/dir-mk-vine.exp b/grading/filesys/dir-mk-vine.exp
new file mode 100644
index 0000000..b555631
--- /dev/null
+++ b/grading/filesys/dir-mk-vine.exp
@@ -0,0 +1,25 @@
+(dir-mk-vine) begin
+(dir-mk-vine) mkdir "0"
+(dir-mk-vine) chdir "0"
+(dir-mk-vine) mkdir "1"
+(dir-mk-vine) chdir "1"
+(dir-mk-vine) mkdir "2"
+(dir-mk-vine) chdir "2"
+(dir-mk-vine) mkdir "3"
+(dir-mk-vine) chdir "3"
+(dir-mk-vine) mkdir "4"
+(dir-mk-vine) chdir "4"
+(dir-mk-vine) mkdir "5"
+(dir-mk-vine) chdir "5"
+(dir-mk-vine) mkdir "6"
+(dir-mk-vine) chdir "6"
+(dir-mk-vine) mkdir "7"
+(dir-mk-vine) chdir "7"
+(dir-mk-vine) mkdir "8"
+(dir-mk-vine) chdir "8"
+(dir-mk-vine) mkdir "9"
+(dir-mk-vine) chdir "9"
+(dir-mk-vine) create "test"
+(dir-mk-vine) chdir "/"
+(dir-mk-vine) open "/0/1/2/3/4/5/6/7/8/9/test"
+(dir-mk-vine) end
diff --git a/grading/filesys/dir-mkdir.c b/grading/filesys/dir-mkdir.c
new file mode 100644
index 0000000..85d243e
--- /dev/null
+++ b/grading/filesys/dir-mkdir.c
@@ -0,0 +1,14 @@
+#include <syscall.h>
+#include "fslib.h"
+
+const char test_name[] = "dir-mkdir";
+
+void
+test_main (void) 
+{
+  check (mkdir ("a"), "mkdir \"a\"");
+  check (create ("a/b", 512), "create \"a/b\"");
+  check (chdir ("a"), "chdir \"a\"");
+  check (open ("b") > 1, "open \"b\"");
+}
+
diff --git a/grading/filesys/dir-mkdir.exp b/grading/filesys/dir-mkdir.exp
new file mode 100644
index 0000000..6dcd01c
--- /dev/null
+++ b/grading/filesys/dir-mkdir.exp
@@ -0,0 +1,6 @@
+(dir-mkdir) begin
+(dir-mkdir) mkdir "a"
+(dir-mkdir) create "a/b"
+(dir-mkdir) chdir "a"
+(dir-mkdir) open "b"
+(dir-mkdir) end
diff --git a/grading/filesys/dir-open.c b/grading/filesys/dir-open.c
new file mode 100644
index 0000000..40550ee
--- /dev/null
+++ b/grading/filesys/dir-open.c
@@ -0,0 +1,22 @@
+#include <syscall.h>
+#include "fslib.h"
+
+const char test_name[] = "dir-open";
+
+void
+test_main (void) 
+{
+  int fd;
+  
+  check (mkdir ("xyzzy"), "mkdir \"xyzzy\"");
+  msg ("open \"xyzzy\"");
+  fd = open ("xyzzy");
+  if (fd == -1) 
+    msg ("open returned -1 -- ok");
+  else 
+    {
+      int retval = write (fd, "foobar", 6);
+      check (retval == -1, "write \"xyzzy\" (must return -1, actually %d)",
+             retval);
+    }
+}
diff --git a/grading/filesys/dir-open.exp b/grading/filesys/dir-open.exp
new file mode 100644
index 0000000..bdb6b67
--- /dev/null
+++ b/grading/filesys/dir-open.exp
@@ -0,0 +1,11 @@
+(dir-open) begin
+(dir-open) mkdir "xyzzy"
+(dir-open) open "xyzzy"
+(dir-open) open returned -1 -- ok
+(dir-open) end
+--OR--
+(dir-open) begin
+(dir-open) mkdir "xyzzy"
+(dir-open) open "xyzzy"
+(dir-open) write "xyzzy" (must return -1, actually -1)
+(dir-open) end
diff --git a/grading/filesys/dir-over-file.c b/grading/filesys/dir-over-file.c
new file mode 100644
index 0000000..01347e1
--- /dev/null
+++ b/grading/filesys/dir-over-file.c
@@ -0,0 +1,11 @@
+#include <syscall.h>
+#include "fslib.h"
+
+const char test_name[] = "dir-over-file";
+
+void
+test_main (void) 
+{
+  check (mkdir ("abc"), "mkdir \"abc\"");
+  check (!create ("abc", 0), "create \"abc\" (must return false)");
+}
diff --git a/grading/filesys/dir-over-file.exp b/grading/filesys/dir-over-file.exp
new file mode 100644
index 0000000..206103b
--- /dev/null
+++ b/grading/filesys/dir-over-file.exp
@@ -0,0 +1,4 @@
+(dir-dir-as-file) begin
+(dir-dir-as-file) mkdir "abc"
+(dir-dir-as-file) create "abc" (must return false)
+(dir-dir-as-file) end
diff --git a/grading/filesys/dir-rm-cwd-cd.c b/grading/filesys/dir-rm-cwd-cd.c
new file mode 100644
index 0000000..fe3febd
--- /dev/null
+++ b/grading/filesys/dir-rm-cwd-cd.c
@@ -0,0 +1,16 @@
+#include <syscall.h>
+#include "fslib.h"
+
+const char test_name[] = "dir-rm-cwd-cd";
+
+void
+test_main (void) 
+{
+  check (mkdir ("a"), "mkdir \"a\"");
+  check (chdir ("a"), "chdir \"a\"");
+  msg ("remove \"/a\" (must not crash)");
+  if (remove ("/a"))
+    check (!chdir ("/a"), "chdir \"/a\" (remove succeeded so this must fail)");
+  else
+    check (chdir ("/a"), "chdir \"/a\" (remove failed so this must succeed)");
+}
diff --git a/grading/filesys/dir-rm-cwd.c b/grading/filesys/dir-rm-cwd.c
new file mode 100644
index 0000000..2754850
--- /dev/null
+++ b/grading/filesys/dir-rm-cwd.c
@@ -0,0 +1,15 @@
+#include <syscall.h>
+#include "fslib.h"
+
+const char test_name[] = "dir-rm-cwd";
+
+void
+test_main (void) 
+{
+  check (mkdir ("a"), "mkdir \"a\"");
+  check (chdir ("a"), "chdir \"a\"");
+  msg ("remove \"/a\" (must not crash)");
+  remove ("/a");
+  msg ("create \"b\" (must not crash)");
+  create ("b", 123);
+}
diff --git a/grading/filesys/dir-rm-cwd.exp b/grading/filesys/dir-rm-cwd.exp
new file mode 100644
index 0000000..ae91c54
--- /dev/null
+++ b/grading/filesys/dir-rm-cwd.exp
@@ -0,0 +1,6 @@
+(dir-rm-cwd) begin
+(dir-rm-cwd) mkdir "a"
+(dir-rm-cwd) chdir "a"
+(dir-rm-cwd) remove "/a" (must not crash)
+(dir-rm-cwd) create "b" (must not crash)
+(dir-rm-cwd) end
diff --git a/grading/filesys/dir-rm-parent.c b/grading/filesys/dir-rm-parent.c
new file mode 100644
index 0000000..9a2136e
--- /dev/null
+++ b/grading/filesys/dir-rm-parent.c
@@ -0,0 +1,17 @@
+#include <syscall.h>
+#include "fslib.h"
+
+const char test_name[] = "dir-rm-parent";
+
+void
+test_main (void) 
+{
+  check (mkdir ("a"), "mkdir \"a\"");
+  check (chdir ("a"), "chdir \"a\"");
+  check (mkdir ("b"), "mkdir \"b\"");
+  check (chdir ("b"), "chdir \"b\"");
+  msg ("remove \"/b\" (must not crash)");
+  remove ("/b");
+  msg ("remove \"/a\" (must not crash)");
+  remove ("/a");
+}
diff --git a/grading/filesys/dir-rm-parent.exp b/grading/filesys/dir-rm-parent.exp
new file mode 100644
index 0000000..863681b
--- /dev/null
+++ b/grading/filesys/dir-rm-parent.exp
@@ -0,0 +1,8 @@
+(dir-rm-parent) begin
+(dir-rm-parent) mkdir "a"
+(dir-rm-parent) chdir "a"
+(dir-rm-parent) mkdir "b"
+(dir-rm-parent) chdir "b"
+(dir-rm-parent) remove "/b" (must not crash)
+(dir-rm-parent) remove "/a" (must not crash)
+(dir-rm-parent) end
diff --git a/grading/filesys/dir-rm-root.c b/grading/filesys/dir-rm-root.c
new file mode 100644
index 0000000..2922824
--- /dev/null
+++ b/grading/filesys/dir-rm-root.c
@@ -0,0 +1,11 @@
+#include <syscall.h>
+#include "fslib.h"
+
+const char test_name[] = "dir-rm-root";
+
+void
+test_main (void) 
+{
+  check (!remove ("/"), "remove \"/\" (must return false)");
+  check (create ("/a", 243), "create \"/a\"");
+}
diff --git a/grading/filesys/dir-rm-root.exp b/grading/filesys/dir-rm-root.exp
new file mode 100644
index 0000000..b6c87cb
--- /dev/null
+++ b/grading/filesys/dir-rm-root.exp
@@ -0,0 +1,4 @@
+(dir-rm-root) begin
+(dir-rm-root) remove "/" (must return false)
+(dir-rm-root) create "/a"
+(dir-rm-root) end
diff --git a/grading/filesys/dir-rm-tree.c b/grading/filesys/dir-rm-tree.c
new file mode 100644
index 0000000..303f257
--- /dev/null
+++ b/grading/filesys/dir-rm-tree.c
@@ -0,0 +1,60 @@
+#include <stdarg.h>
+#include <stdio.h>
+#include <syscall.h>
+#include "fslib.h"
+#include "mk-tree.h"
+
+const char test_name[] = "dir-rm-tree";
+
+static void remove_tree (int at, int bt, int ct, int dt);
+
+void
+test_main (void) 
+{
+  make_tree (4, 3, 3, 4);
+  remove_tree (4, 3, 3, 4);
+}
+
+static void do_remove (const char *format, ...) PRINTF_FORMAT (1, 2);
+
+static void
+remove_tree (int at, int bt, int ct, int dt) 
+{
+  char try[128];
+  int a, b, c, d;
+
+  msg ("removing /0/0/0/0 through /%d/%d/%d/%d...",
+       at - 1, bt - 1, ct - 1, dt - 1);
+  quiet = false;
+  for (a = 0; a < at; a++) 
+    {
+      for (b = 0; b < bt; b++) 
+        {
+          for (c = 0; c < ct; c++) 
+            {
+              for (d = 0; d < dt; d++)
+                do_remove ("/%d/%d/%d/%d", a, b, c, d);
+              do_remove ("/%d/%d/%d", a, b, c);
+            }
+          do_remove ("/%d/%d", a, b);
+        }
+      do_remove ("/%d", a);
+    }
+  quiet = false;
+
+  snprintf (try, sizeof (try), "/%d/%d/%d/%d", at - 1, 0, ct - 1, 0);
+  check (open (try) == -1, "open \"%s\" (must return -1)", try);
+}
+
+static void
+do_remove (const char *format, ...) 
+{
+  char name[128];
+  va_list args;
+
+  va_start (args, format);
+  vsnprintf (name, sizeof name, format, args);
+  va_end (args);
+
+  check (remove (name), "remove \"%s\"", name);
+}
diff --git a/grading/filesys/dir-rm-vine.c b/grading/filesys/dir-rm-vine.c
new file mode 100644
index 0000000..571112a
--- /dev/null
+++ b/grading/filesys/dir-rm-vine.c
@@ -0,0 +1,35 @@
+#include <string.h>
+#include <syscall.h>
+#include "fslib.h"
+
+const char test_name[] = "dir-rm-vine";
+
+void
+test_main (void) 
+{
+  const char *filename = "/0/1/2/3/4/5/6/7/8/9/test";
+  int fd;
+  char tmp[128];
+  
+  tmp[1] = '\0';
+  for (tmp[0] = '0'; tmp[0] <= '9'; tmp[0]++) 
+    {
+      check (mkdir (tmp), "mkdir \"%s\"", tmp);
+      check (chdir (tmp), "chdir \"%s\"", tmp);
+    }
+  check (create ("test", 512), "create \"test\"");
+
+  check (chdir ("/"), "chdir \"/\"");
+  check ((fd = open (filename)) > 1, "open \"%s\"", filename);
+  msg ("close \"%s\"", filename);
+  close (fd);
+
+  strlcpy (tmp, filename, sizeof tmp);
+  while (strlen (tmp) > 0)
+    {
+      check (remove (tmp), "remove \"%s\"", tmp);
+      *strrchr (tmp, '/') = 0;
+    }
+
+  check (open (filename) == 1, "open \"%s\" (must return -1)", filename);
+}
diff --git a/grading/filesys/dir-rmdir.c b/grading/filesys/dir-rmdir.c
new file mode 100644
index 0000000..ed9be64
--- /dev/null
+++ b/grading/filesys/dir-rmdir.c
@@ -0,0 +1,12 @@
+#include <syscall.h>
+#include "fslib.h"
+
+const char test_name[] = "dir-rmdir";
+
+void
+test_main (void) 
+{
+  check (mkdir ("a"), "mkdir \"a\"");
+  check (remove ("a"), "rmdir \"a\"");
+  check (!chdir ("a"), "chdir \"a\" (must return false)");
+}
diff --git a/grading/filesys/dir-rmdir.exp b/grading/filesys/dir-rmdir.exp
new file mode 100644
index 0000000..010c3e0
--- /dev/null
+++ b/grading/filesys/dir-rmdir.exp
@@ -0,0 +1,5 @@
+(dir-rmdir) begin
+(dir-rmdir) mkdir "a"
+(dir-rmdir) rmdir "a"
+(dir-rmdir) chdir "a" (must return false)
+(dir-rmdir) end
diff --git a/grading/filesys/dir-under-file.c b/grading/filesys/dir-under-file.c
new file mode 100644
index 0000000..2565a27
--- /dev/null
+++ b/grading/filesys/dir-under-file.c
@@ -0,0 +1,11 @@
+#include <syscall.h>
+#include "fslib.h"
+
+const char test_name[] = "dir-under-file";
+
+void
+test_main (void) 
+{
+  check (create ("abc", 0), "create \"abc\"");
+  check (!mkdir ("abc"), "mkdir \"abc\" (must return false)");
+}
diff --git a/grading/filesys/dir-under-file.exp b/grading/filesys/dir-under-file.exp
new file mode 100644
index 0000000..8bbdca7
--- /dev/null
+++ b/grading/filesys/dir-under-file.exp
@@ -0,0 +1,4 @@
+(dir-under-file) begin
+(dir-under-file) create "abc"
+(dir-under-file) mkdir "abc" (must return false)
+(dir-under-file) end
diff --git a/grading/filesys/fslib.c b/grading/filesys/fslib.c
index 36f67f8..a94a0d1 100644
--- a/grading/filesys/fslib.c
+++ b/grading/filesys/fslib.c
@@ -4,21 +4,14 @@
 #include <stdio.h>
 #include <string.h>
 #include <syscall.h>
-#include "../lib/arc4.h"
 
 bool quiet = false;
 
 static void
-vmsg (const char *format, va_list args, bool failure) 
+vmsg (const char *format, va_list args) 
 {
-  if (quiet && !failure)
-    return;
-  
   printf ("(%s) ", test_name);
   vprintf (format, args);
-  if (failure)
-    printf (": FAILED");
-  printf ("\n");
 }
 
 void
@@ -26,8 +19,11 @@ msg (const char *format, ...)
 {
   va_list args;
 
+  if (quiet)
+    return;
   va_start (args, format);
-  vmsg (format, args, false);
+  vmsg (format, args);
+  printf ("\n");
   va_end (args);
 }
 
@@ -36,10 +32,9 @@ fail (const char *format, ...)
 {
   va_list args;
 
-  quiet = false;
-  
   va_start (args, format);
-  vmsg (format, args, true);
+  vmsg (format, args);
+  printf (": FAILED\n");
   va_end (args);
 
   exit (1);
@@ -53,30 +48,30 @@ check (bool success, const char *format, ...)
   va_start (args, format);
   if (success) 
     {
-      if (!quiet)
-        vmsg (format, args, false); 
+      if (!quiet) 
+        {
+          vmsg (format, args); 
+          printf ("\n"); 
+        }
     }
   else 
     {
-      vmsg (format, args, true);
+      vmsg (format, args); 
+      printf (": FAILED\n");
       exit (1);
     }
   va_end (args);
 }
 
 void 
-seq_test (const char *filename, void *buf, size_t size,
-          size_t initial_size, int seed,
+seq_test (const char *filename, void *buf, size_t size, size_t initial_size,
           size_t (*block_size_func) (void),
           void (*check_func) (int fd, long ofs)) 
 {
-  static struct arc4 arc4;
   size_t ofs;
   int fd;
   
-  arc4_init (&arc4, &seed, sizeof seed);
-  arc4_crypt (&arc4, buf, size);
-
+  random_bytes (buf, size);
   check (create (filename, initial_size), "create \"%s\"", filename);
   check ((fd = open (filename)) > 1, "open \"%s\"", filename);
 
diff --git a/grading/filesys/fslib.h b/grading/filesys/fslib.h
index b157598..a0e6f32 100644
--- a/grading/filesys/fslib.h
+++ b/grading/filesys/fslib.h
@@ -13,10 +13,14 @@ void fail (const char *, ...) PRINTF_FORMAT (1, 2) NO_RETURN;
 void check (bool, const char *, ...) PRINTF_FORMAT (2, 3);
 
 void shuffle (void *, size_t cnt, size_t size);
+
 void seq_test (const char *filename,
-               void *buffer, size_t size,
-               size_t initial_size, int seed,
-               size_t (*block_size) (void), void (*check) (int fd, long ofs));
+               void *buf, size_t size, size_t initial_size,
+               size_t (*block_size_func) (void),
+               void (*check_func) (int fd, long ofs));
+
 void check_file (const char *filename, const void *buf, size_t filesize);
 
+void test_main (void);
+
 #endif /* fslib.h */
diff --git a/grading/filesys/fsmain.c b/grading/filesys/fsmain.c
new file mode 100644
index 0000000..76113a6
--- /dev/null
+++ b/grading/filesys/fsmain.c
@@ -0,0 +1,12 @@
+#include <random.h>
+#include "fslib.h"
+
+int
+main (void) 
+{
+  msg ("begin");
+  random_init (0);
+  test_main ();
+  msg ("end");
+  return 0;
+}
diff --git a/grading/filesys/full.inc b/grading/filesys/full.inc
index 32b7c8f..25ffe71 100644
--- a/grading/filesys/full.inc
+++ b/grading/filesys/full.inc
@@ -10,11 +10,10 @@ return_test_size (void)
   return TEST_SIZE;
 }
 
-int
-main (void) 
+void
+test_main (void) 
 {
-  msg ("begin");
-  seq_test ("quux", buf, sizeof buf, sizeof buf, 2, return_test_size, NULL);
-  msg ("end");
-  return 0;
+  seq_test ("quux",
+            buf, sizeof buf, sizeof buf,
+            return_test_size, NULL);
 }
diff --git a/grading/filesys/grow-dir.inc b/grading/filesys/grow-dir.inc
index df3cbdf..86a471f 100644
--- a/grading/filesys/grow-dir.inc
+++ b/grading/filesys/grow-dir.inc
@@ -12,12 +12,11 @@ return_block_size (void)
   return sizeof buf;
 }
 
-int
-main (void) 
+void
+test_main (void) 
 {
   size_t i;
   
-  msg ("begin");
 #ifdef DIRECTORY
   check (mkdir (DIRECTORY), "mkdir %s", DIRECTORY);
 #define DIR_PREFIX DIRECTORY "/"
@@ -32,10 +31,9 @@ main (void)
       msg ("creating and checking \"%s\"", filename);
 
       quiet = true;
-      seq_test (filename, buf, sizeof buf, sizeof buf, 0,
+      seq_test (filename,
+                buf, sizeof buf, sizeof buf,
                 return_block_size, NULL); 
       quiet = false;
     }
-  msg ("end");
-  return 0;
 }
diff --git a/grading/filesys/grow-file-size.c b/grading/filesys/grow-file-size.c
index b92ec5b..cf36c17 100644
--- a/grading/filesys/grow-file-size.c
+++ b/grading/filesys/grow-file-size.c
@@ -21,12 +21,10 @@ check_file_size (int fd, long ofs)
           ofs, size);
 }
 
-int
-main (void) 
+void
+test_main (void) 
 {
-  msg ("begin");
-  seq_test ("testfile", buf, sizeof buf, 0, 0,
+  seq_test ("testfile",
+            buf, sizeof buf, 0,
             return_block_size, check_file_size);
-  msg ("end");
-  return 0;
 }
diff --git a/grading/filesys/grow-file-size.exp b/grading/filesys/grow-file-size.exp
index fcb5ce4..6c8f2ea 100644
--- a/grading/filesys/grow-file-size.exp
+++ b/grading/filesys/grow-file-size.exp
@@ -6,4 +6,3 @@
 (grow-file-size) open "testfile" for verification
 (grow-file-size) close "testfile"
 (grow-file-size) end
-
diff --git a/grading/filesys/grow-seq.inc b/grading/filesys/grow-seq.inc
index 2c0e3ba..8a32cd0 100644
--- a/grading/filesys/grow-seq.inc
+++ b/grading/filesys/grow-seq.inc
@@ -10,11 +10,10 @@ return_block_size (void)
   return 1234;
 }
 
-int
-main (void) 
+void
+test_main (void) 
 {
-  msg ("begin");
-  seq_test ("testme", buf, sizeof buf, 0, 3, return_block_size, NULL);
-  msg ("end");
-  return 0;
+  seq_test ("testme",
+            buf, sizeof buf, 0,
+            return_block_size, NULL);
 }
diff --git a/grading/filesys/grow-sparse.c b/grading/filesys/grow-sparse.c
index 6180828..896b2fa 100644
--- a/grading/filesys/grow-sparse.c
+++ b/grading/filesys/grow-sparse.c
@@ -6,13 +6,12 @@
 const char test_name[] = "grow-sparse";
 static char buf[76543];
 
-int
-main (void) 
+void
+test_main (void) 
 {
   char zero = 0;
   int fd;
   
-  msg ("begin");
   check (create ("testfile", 0), "create \"testfile\"");
   check ((fd = open ("testfile")) > 1, "open \"testfile\"");
   msg ("seek \"testfile\"");
@@ -21,6 +20,4 @@ main (void)
   msg ("close \"testfile\"");
   close (fd);
   check_file ("testfile", buf, sizeof buf);
-  msg ("end");
-  return 0;
 }
diff --git a/grading/filesys/grow-tell.c b/grading/filesys/grow-tell.c
index 4f9d517..672786a 100644
--- a/grading/filesys/grow-tell.c
+++ b/grading/filesys/grow-tell.c
@@ -21,11 +21,10 @@ check_tell (int fd, long ofs)
           ofs, pos);
 }
 
-int
-main (void) 
+void
+test_main (void) 
 {
-  msg ("begin");
-  seq_test ("foobar", buf, sizeof buf, 0, 1, return_block_size, check_tell);
-  msg ("end");
-  return 0;
+  seq_test ("foobar",
+            buf, sizeof buf, 0,
+            return_block_size, check_tell);
 }
diff --git a/grading/filesys/grow-too-big.c b/grading/filesys/grow-too-big.c
new file mode 100644
index 0000000..5711693
--- /dev/null
+++ b/grading/filesys/grow-too-big.c
@@ -0,0 +1,22 @@
+/* -*- c -*- */
+
+#include <limits.h>
+#include <syscall.h>
+#include "fslib.h"
+
+const char test_name[] = "grow-sparse";
+
+void
+test_main (void) 
+{
+  char zero = 0;
+  int fd;
+  
+  check (create ("testfile", 0), "create \"testfile\"");
+  check ((fd = open ("testfile")) > 1, "open \"testfile\"");
+  msg ("seek \"testfile\"");
+  seek (fd, UINT_MAX);
+  check (write (fd, &zero, 1) > 0, "write \"testfile\"");
+  msg ("close \"testfile\"");
+  close (fd);
+}
diff --git a/grading/filesys/grow-two-files.c b/grading/filesys/grow-two-files.c
index 8809c60..aa6820a 100644
--- a/grading/filesys/grow-two-files.c
+++ b/grading/filesys/grow-two-files.c
@@ -24,8 +24,8 @@ write_some_bytes (const char *filename, int fd, const char *buf, size_t *ofs)
     }
 }
 
-int
-main (void) 
+void
+test_main (void) 
 {
   int fd_a, fd_b;
   size_t ofs_a, ofs_b;
@@ -55,6 +55,4 @@ main (void)
 
   check_file ("a", buf_a, FILE_SIZE);
   check_file ("b", buf_b, FILE_SIZE);
-
-  return 0;
 }
diff --git a/grading/filesys/main.c b/grading/filesys/main.c
new file mode 100644
index 0000000..52561bc
--- /dev/null
+++ b/grading/filesys/main.c
@@ -0,0 +1,10 @@
+#include "fslib.h"
+
+int
+main (void) 
+{
+  msg ("begin");
+  test_main ();
+  msg ("end");
+  return 0;
+}
diff --git a/grading/filesys/mk-tree.c b/grading/filesys/mk-tree.c
new file mode 100644
index 0000000..ed0e5c3
--- /dev/null
+++ b/grading/filesys/mk-tree.c
@@ -0,0 +1,65 @@
+#include <stdio.h>
+#include <syscall.h>
+#include "fslib.h"
+#include "mk-tree.h"
+
+static void do_mkdir (const char *format, ...) PRINTF_FORMAT (1, 2);
+static void do_touch (const char *format, ...) PRINTF_FORMAT (1, 2);
+
+void
+make_tree (int at, int bt, int ct, int dt) 
+{
+  char try[128];
+  int a, b, c, d;
+  int fd;
+
+  msg ("creating /0/0/0/0 through /%d/%d/%d/%d...",
+       at - 1, bt - 1, ct - 1, dt - 1);
+  quiet = true;
+  for (a = 0; a < at; a++) 
+    {
+      do_mkdir ("/%d", a);
+      for (b = 0; b < bt; b++) 
+        {
+          do_mkdir ("/%d/%d", a, b);
+          for (c = 0; c < ct; c++) 
+            {
+              do_mkdir ("/%d/%d/%d", a, b, c);
+              for (d = 0; d < dt; d++)
+                do_touch ("/%d/%d/%d/%d", a, b, c, d);
+            }
+        }
+    }
+  quiet = false;
+
+  snprintf (try, sizeof try, "/%d/%d/%d/%d", 0, bt - 1, 0, dt - 1);
+  check ((fd = open (try)) > 1, "open \"%s\"", try);
+  msg ("close \"%s\"", try);
+  close (fd);
+}
+
+static void
+do_mkdir (const char *format, ...) 
+{
+  char dir[128];
+  va_list args;
+
+  va_start (args, format);
+  vsnprintf (dir, sizeof dir, format, args);
+  va_end (args);
+
+  check (mkdir (dir), "mkdir \"%s\"", dir);
+}
+
+static void
+do_touch (const char *format, ...)
+{
+  char file[128];
+  va_list args;
+
+  va_start (args, format);
+  vsnprintf (file, sizeof file, format, args);
+  va_end (args);
+
+  check (create (file, 0), "create \"%s\"", file);
+}
diff --git a/grading/filesys/mk-tree.h b/grading/filesys/mk-tree.h
new file mode 100644
index 0000000..e10334c
--- /dev/null
+++ b/grading/filesys/mk-tree.h
@@ -0,0 +1,6 @@
+#ifndef MK_TREE_H
+#define MK_TREE_H 1
+
+void make_tree (int at, int bt, int ct, int dt);
+
+#endif /* mk-tree.h */
diff --git a/grading/filesys/random.inc b/grading/filesys/random.inc
index e821a59..e720574 100644
--- a/grading/filesys/random.inc
+++ b/grading/filesys/random.inc
@@ -15,14 +15,12 @@
 char buf[TEST_SIZE];
 int order[BLOCK_CNT];
 
-int
-main (void) 
+void
+test_main (void) 
 {
   int fd;
   size_t i;
 
-  msg ("begin");
-
   random_init (57);
   random_bytes (buf, sizeof buf);
 
@@ -64,7 +62,4 @@ main (void)
 
   fail ("close \"bazzle\"");
   close (fd);
-
-  msg ("end");
-  return 0;
 }
diff --git a/grading/filesys/run-tests b/grading/filesys/run-tests
index 7b73487..09c334c 100755
--- a/grading/filesys/run-tests
+++ b/grading/filesys/run-tests
@@ -48,8 +48,17 @@ sub usage {
 
 # Default set of tests.
 @TESTS = qw (sm-create sm-full sm-seq-block sm-seq-random sm-random
+
 	     grow-create grow-seq-sm grow-seq-lg grow-file-size grow-tell
-	     grow-sparse grow-root-sm grow-root-lg grow-dir-lg grow-two-files
+	     grow-sparse grow-too-big grow-root-sm grow-root-lg grow-dir-lg 
+	     grow-two-files
+
+	     dir-mkdir dir-rmdir dir-mk-vine dir-rm-vine dir-mk-tree
+	     dir-rm-tree dir-lsdir dir-rm-cwd dir-rm-cwd-cd
+	     dir-rm-parent dir-rm-root dir-over-file dir-under-file
+	     dir-empty-name dir-open
+
+	     syn-remove syn-read
 	     ) unless @TESTS > 0;
 
 our (%args);
@@ -251,7 +260,8 @@ sub really_run_test {
 
     # Make output directory.
     mkdir "output/$test";
-    xsystem ("pintos make-disk output/$test/fs.dsk 2 >/dev/null 2>&1",
+    my ($fs_size) = $test ne 'grow-too-big' ? 2 : .25;
+    xsystem ("pintos make-disk output/$test/fs.dsk $fs_size >/dev/null 2>&1",
 	     DIE => "failed to create file system disk");
     xsystem ("pintos make-disk output/$test/swap.dsk 2 >/dev/null 2>&1",
 	     DIE => "failed to create swap disk");
@@ -268,6 +278,14 @@ sub really_run_test {
 	if !xsystem ("$pintos_base_cmd put -f $GRADES_DIR/$test $test",
 		     LOG => "$test/put", TIMEOUT => 60, EXPECT => 1);
 
+    my (@extra_files);
+    push (@extra_files, "child-syn-read") if $test eq 'syn-read';
+    for my $fn (@extra_files) {
+	return "format/put error" 
+	    if !xsystem ("$pintos_base_cmd put $GRADES_DIR/$fn $fn",
+			 LOG => "$test/put-$fn", TIMEOUT => 60, EXPECT => 1);
+    }
+    
     # Run.
     my ($timeout) = 60;
     my ($testargs) = defined ($args{$test}) ? " $args{$test}" : "";
diff --git a/grading/filesys/seq-block.inc b/grading/filesys/seq-block.inc
index e5424cd..9dc5d31 100644
--- a/grading/filesys/seq-block.inc
+++ b/grading/filesys/seq-block.inc
@@ -10,12 +10,10 @@ return_block_size (void)
   return BLOCK_SIZE;
 }
 
-int
-main (void) 
+void
+test_main (void) 
 {
-  msg ("begin");
-  seq_test ("noodle", buf, sizeof buf, sizeof buf, 4,
+  seq_test ("noodle",
+            buf, sizeof buf, sizeof buf,
             return_block_size, NULL);
-  msg ("end");
-  return 0;
 }
diff --git a/grading/filesys/seq-random.inc b/grading/filesys/seq-random.inc
index a0e6106..e22ba89 100644
--- a/grading/filesys/seq-random.inc
+++ b/grading/filesys/seq-random.inc
@@ -11,12 +11,11 @@ return_random (void)
   return random_ulong () % 1031 + 1;
 }
 
-int
-main (void) 
+void
+test_main (void) 
 {
-  msg ("begin");
   random_init (-1);
-  seq_test ("nibble", buf, sizeof buf, sizeof buf, 5, return_random, NULL);
-  msg ("end");
-  return 0;
+  seq_test ("nibble",
+            buf, sizeof buf, sizeof buf,
+            return_random, NULL);
 }
diff --git a/grading/filesys/syn-read.c b/grading/filesys/syn-read.c
new file mode 100644
index 0000000..d050db7
--- /dev/null
+++ b/grading/filesys/syn-read.c
@@ -0,0 +1,41 @@
+#include <random.h>
+#include <stdio.h>
+#include <syscall.h>
+#include "fslib.h"
+
+const char test_name[] = "syn-read";
+
+static char buf[1024];
+
+#define CHILD_CNT 10
+
+void
+test_main (void) 
+{
+  const char *filename = "data";
+  pid_t children[CHILD_CNT];
+  int fd;
+  int i;
+
+  check (create (filename, sizeof buf), "create \"%s\"", filename);
+  check ((fd = open (filename)) > 1, "open \"%s\"", filename);
+  random_bytes (buf, sizeof buf);
+  check (write (fd, buf, sizeof buf) > 0, "write \"%s\"", filename);
+  msg ("close \"%s\"", filename);
+  close (fd);
+
+  for (i = 0; i < CHILD_CNT; i++) 
+    {
+      char cmd_line[128];
+      snprintf (cmd_line, sizeof cmd_line,
+                "child-syn-read %d %zu", i, sizeof buf);
+      check ((children[i] = exec (cmd_line)) != PID_ERROR,
+             "exec \"%s\"", cmd_line);
+    }
+
+  for (i = 0; i < CHILD_CNT; i++) 
+    {
+      int status = join (children[i]);
+      check (status == i, "join child %d of %d", i + 1, (int) CHILD_CNT);
+    }
+}
diff --git a/grading/filesys/syn-remove.c b/grading/filesys/syn-remove.c
new file mode 100644
index 0000000..e47456a
--- /dev/null
+++ b/grading/filesys/syn-remove.c
@@ -0,0 +1,28 @@
+#include <random.h>
+#include <string.h>
+#include <syscall.h>
+#include "fslib.h"
+
+const char test_name[] = "syn-remove";
+
+char buf1[1234];
+char buf2[1234];
+
+void
+test_main (void) 
+{
+  const char *filename = "deleteme";
+  int fd;
+  
+  check (create (filename, 0), "create \"%s\"", filename);
+  check ((fd = open (filename)) > 1, "open \"%s\"", filename);
+  check (remove (filename), "remove \"%s\"", filename);
+  random_bytes (buf1, sizeof buf1);
+  check (write (fd, buf1, sizeof buf1) > 0, "write \"%s\"", filename);
+  msg ("seek \"%s\" to 0", filename);
+  seek (fd, 0);
+  check (read (fd, buf2, sizeof buf2) > 0, "read \"%s\"", filename);
+  check (!memcmp (buf1, buf2, sizeof buf1), "compare data read and written");
+  msg ("close \"%s\"", filename);
+  close (fd);
+}
diff --git a/grading/filesys/syn-remove.exp b/grading/filesys/syn-remove.exp
new file mode 100644
index 0000000..f4ad702
--- /dev/null
+++ b/grading/filesys/syn-remove.exp
@@ -0,0 +1,10 @@
+(syn-remove) begin
+(syn-remove) create "deleteme"
+(syn-remove) open "deleteme"
+(syn-remove) remove "deleteme"
+(syn-remove) write "deleteme"
+(syn-remove) seek "deleteme" to 0
+(syn-remove) read "deleteme"
+(syn-remove) compare data read and written
+(syn-remove) close "deleteme"
+(syn-remove) end
diff --git a/grading/filesys/tests.txt b/grading/filesys/tests.txt
index 901f5a1..837ca2b 100644
--- a/grading/filesys/tests.txt
+++ b/grading/filesys/tests.txt
@@ -24,6 +24,7 @@ File growth
   grow-file-size: filesize must return proper value as file grows
   grow-tell: tell must return proper value as file grows
   grow-sparse: create empty file, seek past 64 kB, write byte, verify zeroing
+  grow-too-big: create empty file, seek past 2 GB, write byte, must not crash
   grow-root-sm: create 20 small files in root directory
   grow-root-lg: create 50 small files in root directory
   grow-dir-lg: create subdirectory, create 50 small files in it
@@ -31,22 +32,21 @@ File growth
 Score: /
 
 Subdirectories and file management
-  dir-mkdir: create directory and chdir into it
+  dir-mkdir: mkdir a, create a/b, chdir a, open b
   dir-rmdir: create directory, remove directory, chdir into it must now fail
-  dir-mk-vine: create deep chain of directories
+  dir-mk-vine: create deep chain of directories, create & check files in them
   dir-rm-vine: create and remove deep chain of directories
-  dir-mk-tree: create wide, deep directory tree
+  dir-mk-tree: create wide, deep directory tree, create & check files in it
   dir-rm-tree: create and remove wide, deep directory tree
-  dir-rel-mkdir: mkdir /a, chdir /a, mkdir b, chdir b, create /a/b/c, open c
-  dir-rel-open: mkdir /a, mkdir /a/b, create /a/b/c, chdir /a, open b/c
-  dir-rel-rmdir: mkdir a, mkdir /a/b, chdir a, rmdir b
-  dir-rel-remove: mkdir a, create /a/b, chdir a, remove b
-  dir-abs-mkdir: mkdir /a, chdir /a, mkdir /b, create /b/c, chdir /b, open c
   dir-lsdir: lsdir must work
   dir-rm-cwd: removing current directory must not crash
-  dir-rm-cwd-cd: if current directory removed then cd'ing to it must fail
+  dir-rm-cwd-cd: if current directory removable, then cd'ing to it must fail
   dir-rm-parent: removing current directory and then its parent must not crash
-  dir-open: if directories can be opened as file, then writing them must fail
+  dir-rm-root: must not be able to remove root directory
+  dir-over-file: creating a directory named after an existing file must fail
+  dir-under-file: creating a file named after an existing directory must fail
+  dir-empty-name: creating a file named after the empty string must fail
+  dir-open: if directories can be opened as files, then writing them must fail
 Score: /
 
 Synchronization
-- 
2.30.2