Add Emacs and Vim keybindings for navigation

Add basic Control key combinations to handling_keys() for scrolling:
- C-n / C-p for line navigation (Emacs style)
- C-d / C-v for half-page down (Vim/Emacs style)
- C-u / M-v for half-page up (Vim/Emacs style)

1 files changed, 28 insertions, 0 deletions

diff --git a/src/keys.c b/src/keys.c
index bc4b7f2..440737d 100644
--- a/src/keys.c
+++ b/src/keys.c
@@ -12,9 +12,37 @@
 #include "mem.h"
 #include "wm.h"
 
+bool keymap = false;
+
 void
 handling_keys(int ch, fm_info *i)
 {
+	/* Control(C) or Alt(M) */
+	if (ch < 32) {
+		log_write(LOG_INFO, "ch = %d", ch);
+		switch (ch) {
+		case 14: /* C-n, scroll down in Emacs*/
+			fm_entries_scroll(i, 1);
+			break;
+		case 16: /* C-p scroll up in Emacs */
+			fm_entries_scroll(i, -1);
+			break;
+			/* Page down */
+		case 4:	 /* C-d, for Vi users' habit */
+		case 22: /* C-v, for Emacs users' habit*/
+			fm_entries_scroll(i, i->windows[PANE_LEFT]->height / 2);
+			break;
+			/* Page up */
+		case 21: /* C-u */
+		case 27: /* M-v */
+			fm_entries_scroll(i,
+					  -(i->windows[PANE_LEFT]->height / 2));
+			break;
+		}
+
+		return;
+	}
+
 	switch (ch) {
 #ifdef KEY_RESIZE
 	case KEY_RESIZE: