Author: Trent Buck <address@hidden>
Patched-Against: cvs2004-07-02
Description: 
 Adds :undo, which allows (repeated) undoing of frame operations.
Todo:
 * Make undo limit a variable (set with :set)
 * Put prototypes and shit in the right files.
 * Typedef the struct.
 * Make it work with class and sfdump patches.
 * Avoid extending linkedlist.h.

diff -ur ratpoison.orig/src/actions.c ratpoison/src/actions.c
--- ratpoison.orig/src/actions.c	2004-05-20 22:40:02.000000000 +1000
+++ ratpoison/src/actions.c	2004-07-02 17:00:44.000000000 +1000
@@ -31,6 +31,9 @@
 
 /* rp_keymaps is ratpoison's list of keymaps. */
 LIST_HEAD(rp_keymaps);
+LIST_HEAD(rp_frame_histories);
+int num_frame_histories;
+#define MAX_FRAME_HISTORIES 20
 
 static user_command user_commands[] = 
   { /address@hidden (tag required for genrpbindings) */
@@ -105,6 +108,7 @@
     {"title", 		cmd_rename, 		arg_STRING},
     {"tmpwm",		cmd_tmpwm,		arg_STRING},
     {"unalias",		cmd_unalias,		arg_STRING},
+    {"undo",		cmd_undo,		arg_STRING},
     {"unmanage",	cmd_unmanage,		arg_STRING},
     {"unsetenv",	cmd_unsetenv,		arg_STRING},
     {"verbexec", 	cmd_verbexec, 		arg_STRING},
@@ -1367,6 +1371,7 @@
 char *
 cmd_newwm(int interactive, char *data)
 {
+  push_frame_history (current_screen());
   char *prog;
 
   if (data == NULL)
@@ -1658,6 +1663,7 @@
 char *
 cmd_v_split (int interactive, char *data)
 {
+  push_frame_history (current_screen());
   rp_frame *frame;
   int pixels;
 
@@ -1680,6 +1686,7 @@
 char *
 cmd_h_split (int interactive, char *data)
 {
+  push_frame_history (current_screen());
   rp_frame *frame;
   int pixels;
 
@@ -1702,6 +1709,7 @@
 char *
 cmd_only (int interactive, char *data)
 {
+  push_frame_history (current_screen());
   remove_all_splits();
   maximize (current_window());
 
@@ -1711,6 +1719,7 @@
 char *
 cmd_remove (int interactive, char *data)
 {
+  push_frame_history (current_screen());
   rp_screen *s = current_screen();
   rp_frame *frame;
 
@@ -1735,6 +1744,7 @@
 char *
 cmd_shrink (int interactive, char *data)
 {
+  push_frame_history (current_screen());
   resize_shrink_to_window (current_frame());
   return NULL;
 }
@@ -1742,6 +1752,7 @@
 char *
 cmd_resize (int interactive, char *data)
 {
+  push_frame_history (current_screen());
   rp_screen *s = current_screen ();
 
   /* If the user calls resize with arguments, treat it like the
@@ -3446,8 +3457,8 @@
   return NULL;
 }
 
-char *
-cmd_fdump (int interactively, char *data)
+static char *
+fdump (rp_screen *screen)
 {
   struct sbuf *s;
   char *tmp;
@@ -3456,7 +3467,7 @@
   s = sbuf_new (0);
 
   /* FIXME: Oooh, gross! there's a trailing comma, yuk! */
-  list_for_each_entry (cur, &current_screen()->frames, node)
+  list_for_each_entry (cur, &(screen->frames), node)
     {
       char *tmp;
 
@@ -3472,9 +3483,21 @@
 }
 
 char *
+cmd_fdump (int interactively, char *data)
+{
+  return fdump (current_screen());
+}
+
+char *
 cmd_frestore (int interactively, char *data)
 {
-  rp_screen *s = current_screen();
+  push_frame_history (current_screen());
+  return frestore (interactively, data, current_screen());
+}
+
+char *
+frestore (int interactively, char *data, rp_screen *s)
+{
   char *token;
   char *dup;
   rp_frame *new, *cur;
@@ -4298,3 +4321,56 @@
     free (rest);
   return NULL;
 }
+
+void 
+push_frame_history(struct rp_screen *screen)
+{
+  struct rp_frame_history *cur;
+  if (num_frame_histories > MAX_FRAME_HISTORIES)
+    {
+      /* Delete the oldest node */
+      list_last (cur, &rp_frame_histories, node);
+      remove_frame_history (cur);
+      num_frame_histories--;
+    }
+  cur = xmalloc (sizeof(struct rp_frame_history));
+  cur->frames = fdump(screen);
+  cur->screen = screen;
+  list_add (&cur->node, &rp_frame_histories);
+  num_frame_histories++;
+}
+
+char *
+cmd_undo (int interactive, char *data)
+{
+  /* assert(!data); */
+  struct rp_frame_history *cur;
+
+  list_first (cur, &rp_frame_histories, node);
+  if (NULL == cur)
+    {
+      message (" No more undo information available ");
+      return NULL;
+    }
+  else
+    {
+      char *ret;
+
+      ret = frestore (interactive, cur->frames, cur->screen);
+      /* Delete the newest node */
+      remove_frame_history (cur);
+      num_frame_histories--;
+      return ret;
+    }
+}
+
+void
+remove_frame_history (struct rp_frame_history *f)
+{
+  if (NULL == f)
+    return;
+  if (f->frames)
+    free (f->frames);
+  list_del (&(f->node));
+}
+
diff -ur ratpoison.orig/src/actions.h ratpoison/src/actions.h
--- ratpoison.orig/src/actions.h	2004-04-19 11:30:39.000000000 +1000
+++ ratpoison/src/actions.h	2004-07-02 16:51:22.000000000 +1000
@@ -133,5 +133,9 @@
 rp_action* find_keybinding (KeySym keysym, int state, rp_keymap *map);
 rp_action* find_keybinding_by_action (char *action, rp_keymap *map);
 
+void push_frame_history(rp_screen *);
+char *cmd_undo (int, char *);
+void remove_frame_history (struct rp_frame_history *f);
+char *frestore (int interactively, char *data, rp_screen *s);
 
 #endif /* ! _RATPOISON_ACTIONS_H */
diff -ur ratpoison.orig/src/data.h ratpoison/src/data.h
--- ratpoison.orig/src/data.h	2004-05-20 22:40:02.000000000 +1000
+++ ratpoison/src/data.h	2004-07-02 16:47:54.000000000 +1000
@@ -325,4 +325,11 @@
   struct list_head *hook;
 };
 
+struct rp_frame_history
+{
+  char *frames;
+  rp_screen *screen;
+  struct list_head node;
+};
+
 #endif /* _RATPOISON_DATA_H */
diff -ur ratpoison.orig/src/linkedlist.h ratpoison/src/linkedlist.h
--- ratpoison.orig/src/linkedlist.h	2003-05-27 17:51:07.000000000 +1000
+++ ratpoison/src/linkedlist.h	2004-07-02 15:20:01.000000000 +1000
@@ -180,3 +180,11 @@
   if (&first->member == (head))					\
     first = NULL;						\
 }
+
+/* Return the last element in the list. */
+#define list_last(last, head, member)				\
+{								\
+  last = list_entry((head)->prev, typeof(*last), member);	\
+  if (&last->member == (head))					\
+    last = NULL;						\
+}