1 files changed, 53 insertions, 0 deletions
diff --git a/src/tests/filesys/extended/child-syn-rw.c b/src/tests/filesys/extended/child-syn-rw.c
new file mode 100644
index 0000000..0e2217d
--- /dev/null
+++ b/src/tests/filesys/extended/child-syn-rw.c
@@ -0,0 +1,53 @@
+/* Child process for syn-rw.
+   Reads from a file created by our parent process, which is
+   growing it.  We loop until we've read the whole file
+   successfully.  Many iterations through the loop will return 0
+   bytes, because the file has not grown in the meantime.  That
+   is, we are "busy waiting" for the file to grow.
+   (This test could be improved by adding a "yield" system call
+   and calling yield whenever we receive a 0-byte read.) */
+
+#include <random.h>
+#include <stdlib.h>
+#include <syscall.h>
+#include "tests/filesys/extended/syn-rw.h"
+#include "tests/lib.h"
+
+const char *test_name = "child-syn-rw";
+
+static char buf1[BUF_SIZE];
+static char buf2[BUF_SIZE];
+
+int
+main (int argc, const char *argv[]) 
+{
+  int child_idx;
+  int fd;
+  size_t ofs;
+
+  quiet = true;
+  
+  CHECK (argc == 2, "argc must be 2, actually %d", argc);
+  child_idx = atoi (argv[1]);
+
+  random_init (0);
+  random_bytes (buf1, sizeof buf1);
+
+  CHECK ((fd = open (file_name)) > 1, "open \"%s\"", file_name);
+  ofs = 0;
+  while (ofs < sizeof buf2)
+    {
+      int bytes_read = read (fd, buf2 + ofs, sizeof buf2 - ofs);
+      CHECK (bytes_read >= -1 && bytes_read <= (int) (sizeof buf2 - ofs),
+             "%zu-byte read on \"%s\" returned invalid value of %d",
+             sizeof buf2 - ofs, file_name, bytes_read);
+      if (bytes_read > 0) 
+        {
+          compare_bytes (buf2 + ofs, buf1 + ofs, bytes_read, ofs, file_name);
+          ofs += bytes_read;
+        }
+    }
+  close (fd);
+
+  return child_idx;
+}