Merge branch 'user-programs-temporary-fix' into 'user-programs'

Temporary fixes for process waiting and stack setup to allow simple user programs to run

See merge request lab2425_autumn/pintos_22!24

src/userprog/process.c

@@ -17,6 +17,7 @@
 #include "threads/palloc.h"
 #include "threads/thread.h"
 #include "threads/vaddr.h"
+#include "devices/timer.h"
 
 static thread_func start_process NO_RETURN;
 static bool load (const char *cmdline, void (**eip) (void), void **esp);
@@ -88,7 +89,12 @@ start_process (void *file_name_)
 int
 process_wait (tid_t child_tid UNUSED) 
 {
-  return -1;
+  /* As a temporary wait, waiting will just put the thread to sleep for one
+     second (TIMER_FREQ = 100 ticks ~ 1 second). */
+  /* TODO: Implement process_wait () correctly. Remove the next line. */
+  timer_sleep (TIMER_FREQ);
+
+  return 0; /* TODO: Change this too */
 }
 
 /* Free the current process's resources. */
@@ -451,7 +457,7 @@ setup_stack (void **esp)
     {
       success = install_page (((uint8_t *) PHYS_BASE) - PGSIZE, kpage, true);
       if (success)
-        *esp = PHYS_BASE;
+        *esp = PHYS_BASE - 12;
       else
         palloc_free_page (kpage);
     }