i hate this job

pintos-env/pintos/userprog/process.c

@@ -17,6 +17,18 @@
 #include "threads/palloc.h"
 #include "threads/thread.h"
 #include "threads/vaddr.h"
+#include "lib/kernel/list.h"
+
+static struct arg {
+  struct list_elem elem;
+  char* data;
+  void* addr;
+};
+
+struct arguments {
+  int argc;
+  char** argv;
+};
 
 static thread_func start_process NO_RETURN;
 static bool load (const char *cmdline, void (**eip) (void), void **esp);
@@ -50,22 +62,99 @@ process_execute (const char *file_name)
 static void
 start_process (void *file_name_)
 {
-  char *file_name = file_name_;
+  char *cmdline = file_name_;
+
   struct intr_frame if_;
   bool success;
 
+  // Populate the stack
+  struct list arg_list;
+  list_init(&arg_list);
+
+  char *token, *save_ptr;
+
+  // tokenize cmdline
+  for (token = strtok_r(cmdline, " ", &save_ptr); token != NULL;
+      token = strtok_r(NULL, " ", &save_ptr)) {
+        struct arg* it = malloc(sizeof(struct arg));
+        it->data = token;
+        printf("list_elem pushed: %s\n", token);
+        list_push_back(&arg_list, it);
+  }
+
+  list_reverse(&arg_list);
+
+  printf("ciao mamma!\n");
+  struct list_elem* e;
+  for (e = list_begin(&arg_list); e != list_end(&arg_list); e = list_next(e)) {
+		struct arg* i = list_entry(e, struct arg, elem);
+    printf("list_elem: %s\n", i->data);
+	}
+  
+  // put argv[i][...] on stack and keep track of addresses
+  char* program_name;
+  for (e = list_begin(&arg_list); e != list_end(&arg_list); e = list_next(e)) {
+		struct arg* i = list_entry(e, struct arg, elem);
+    size_t bytes = strlen(i->data) + 1;
+		if_.esp -= bytes;
+    i->addr = if_.esp;
+    memcpy(&(if_.esp), i->data, bytes);
+	}
+
+  // put terminator of argv[] (argv[4] in example)
+  size_t bytes = sizeof(void*); // size of pointers on stack
+  if_.esp -= bytes;
+  printf("bytes: %d %X\n", bytes, if_.esp);
+  
+  {
+    uint32_t write[1] = {0};
+    memcpy(&(if_.esp), write, sizeof(uint32_t));
+  }
+
+  // put addresses of argv[i] on stack
+  for (e = list_begin(&arg_list); e != list_end(&arg_list);) {
+		struct arg* i = list_entry(e, struct arg, elem);
+		if_.esp -= bytes;
+    {
+      uint32_t write[1] = {i->addr};
+      memcpy(&(if_.esp), write, sizeof(uint32_t));
+    }
+    e = list_next(e);
+    
+	}
+
+  //put argv
+  if_.esp -= bytes;
+  {
+    uint32_t write[1] = {if_.esp + bytes};
+    memcpy(&(if_.esp), write, sizeof(uint32_t));
+  }
+  //put argc
+  if_.esp -= bytes;
+  {
+    uint32_t write[1] = {list_size(&arg_list) - 1};
+    memcpy(&(if_.esp), write, sizeof(uint32_t));
+  }
+
+  //put return address
+  if_.esp -= bytes;
+  {
+    uint32_t write[1] = {0};
+    memcpy(&(if_.esp), write, sizeof(uint32_t));
+  }
+ 
   /* Initialize interrupt frame and load executable. */
   memset (&if_, 0, sizeof if_);
   if_.gs = if_.fs = if_.es = if_.ds = if_.ss = SEL_UDSEG;
   if_.cs = SEL_UCSEG;
   if_.eflags = FLAG_IF | FLAG_MBS;
-  success = load (file_name, &if_.eip, &if_.esp);
+  success = load (program_name, &if_.eip, &if_.esp);
 
   /* If load failed, quit. */
-  palloc_free_page (file_name);
+  palloc_free_page (program_name);
   if (!success) 
     thread_exit ();
-
+  
   /* Start the user process by simulating a return from an
      interrupt, implemented by intr_exit (in
      threads/intr-stubs.S).  Because intr_exit takes all of its