More VM tests.

[pintos-anon] / grading / vm / page-merge-par.c

diff --git a/grading/vm/page-merge-par.c b/grading/vm/page-merge-par.c
new file mode 100644 (file)
index 0000000..93ceb24
--- /dev/null
+++ b/grading/vm/page-merge-par.c
@@ -0,0 +1,167 @@
+#include <stdio.h>
+#include <stdlib.h>
+#ifdef PINTOS
+#include <syscall.h>
+#else
+#include "posix-compat.h"
+#endif
+#include "arc4.h"
+
+#define CHUNK_SIZE (63 * 1024)                  /* Max file size. */
+#define CHUNK_CNT 8                             /* Number of chunks. */
+#define DATA_SIZE (CHUNK_CNT * CHUNK_SIZE)      /* Buffer size. */
+
+unsigned char buf1[DATA_SIZE], buf2[DATA_SIZE];
+size_t histogram[256];
+
+/* Initialize buf1 with random data,
+   then count the number of instances of each value within it. */
+static void
+init (void) 
+{
+  struct arc4 arc4;
+  size_t i;
+
+  printf ("page-merge-par) init\n");
+
+  arc4_init (&arc4, "foobar", 6);
+  arc4_crypt (&arc4, buf1, sizeof buf1);
+  for (i = 0; i < sizeof buf1; i++)
+    histogram[buf1[i]]++;
+}
+
+/* Sort each chunk of buf1 using a subprocess. */
+static void
+sort (void)
+{
+  pid_t children[CHUNK_CNT];
+  size_t i;
+
+  for (i = 0; i < CHUNK_CNT; i++) 
+    {
+      char fn[128];
+      char cmd[128];
+      int fd;
+
+      printf ("(page-merge-par) sort chunk %zu\n", i);
+
+      /* Write this chunk to a file. */
+      snprintf (fn, sizeof fn, "buf%d", i);
+      create (fn, CHUNK_SIZE);
+      fd = open (fn);
+      if (fd < 0) 
+        {
+          printf ("(page-merge-par) open() failed\n");
+          exit (1);
+        }
+      write (fd, buf1 + CHUNK_SIZE * i, CHUNK_SIZE);
+      close (fd);
+
+      /* Sort with subprocess. */
+      snprintf (cmd, sizeof cmd, "child-sort %s", fn);
+      children[i] = exec (cmd);
+      if (children[i] == -1) 
+        {
+          printf ("(page-merge-par) exec() failed\n");
+          exit (1);
+        } 
+    }
+
+  for (i = 0; i < CHUNK_CNT; i++) 
+    {
+      char fn[128];
+      int fd;
+
+      if (join (children[i]) != 123) 
+        {
+          printf ("(page-merge-par) join(exec()) returned bad value\n");
+          exit (1);
+        }
+
+      /* Read chunk back from file. */
+      snprintf (fn, sizeof fn, "buf%d", i);
+      fd = open (fn);
+      if (fd < 0) 
+        {
+          printf ("(page-merge-par) open() failed\n");
+          exit (1);
+        }
+      read (fd, buf1 + CHUNK_SIZE * i, CHUNK_SIZE);
+      close (fd);
+    }
+}
+
+/* Merge the sorted chunks in buf1 into a fully sorted buf2. */
+static void
+merge (void) 
+{
+  unsigned char *mp[CHUNK_CNT];
+  size_t mp_left;
+  unsigned char *op;
+  size_t i;
+
+  printf ("(page-merge-par) merge\n");
+
+  /* Initialize merge pointers. */
+  mp_left = CHUNK_CNT;
+  for (i = 0; i < CHUNK_CNT; i++)
+    mp[i] = buf1 + CHUNK_SIZE * i;
+
+  /* Merge. */
+  op = buf2;
+  while (mp_left > 0) 
+    {
+      /* Find smallest value. */
+      size_t min = 0;
+      for (i = 1; i < mp_left; i++)
+        if (*mp[i] < *mp[min])
+          min = i;
+
+      /* Append value to buf2. */
+      *op++ = *mp[min];
+
+      /* Advance merge pointer.
+         Delete this chunk from the set if it's emptied. */
+      if ((++mp[min] - buf1) % CHUNK_SIZE == 0) 
+        mp[min] = mp[--mp_left];
+    }
+}
+
+static void
+verify (void) 
+{
+  size_t buf_idx;
+  size_t hist_idx;
+
+  printf ("(page-merge-par) verify\n");
+
+  buf_idx = 0;
+  for (hist_idx = 0; hist_idx < sizeof histogram / sizeof *histogram;
+       hist_idx++)
+    {
+      while (histogram[hist_idx]-- > 0) 
+        {
+          if (buf2[buf_idx] != hist_idx)
+            {
+              printf ("(page-merge-par) bad value %d in byte %zu\n",
+                      buf2[buf_idx], buf_idx);
+              exit (1);
+            }
+          buf_idx++;
+        } 
+    }
+
+  printf ("(page-merge-par) success, buf_idx=%zu\n", buf_idx);
+}
+
+int
+main (void) 
+{
+  printf ("(page-merge-par) begin\n");
+  init ();
+  sort ();
+  merge ();
+  verify ();
+  printf ("(page-merge-par) end\n");
+  return 0;
+}