provided code

src/tests/userprog/read-boundary.c

@@ -0,0 +1,30 @@
+/* Reads data spanning two pages in virtual address space,
+   which must succeed. */
+
+#include <string.h>
+#include <syscall.h>
+#include "tests/userprog/boundary.h"
+#include "tests/userprog/sample.inc"
+#include "tests/lib.h"
+#include "tests/main.h"
+
+void
+test_main (void) 
+{
+  int handle;
+  int byte_cnt;
+  char *buffer;
+
+  CHECK ((handle = open ("sample.txt")) > 1, "open \"sample.txt\"");
+
+  buffer = get_boundary_area () - sizeof sample / 2;
+  byte_cnt = read (handle, buffer, sizeof sample - 1);
+  if (byte_cnt != sizeof sample - 1)
+    fail ("read() returned %d instead of %zu", byte_cnt, sizeof sample - 1);
+  else if (strcmp (sample, buffer)) 
+    {
+      msg ("expected text:\n%s", sample);
+      msg ("text actually read:\n%s", buffer);
+      fail ("expected text differs from actual");
+    }
+}