"fix backspace, get left/right working (in insert mode though...)"

src/main.c

@@ -13,29 +13,55 @@ MSH_ENTRY_POINT {
     int out;
     char *buf = msh_callocate(2048, sizeof(char));
     int i = 0, n = 0, last = 0;
-    unsigned long long sz = 0;
+    SIZE_TYPE sz = 0, leftoff = 0;
 
     msh_print_strings(msh_working_directory(), " %> ", 0);
 
-    while ((out = msh_read_input(buf, &sz, 2048)), out > 0) {
+    while ((out = msh_read_input(buf, &sz, 2048)), out != -1) {
       switch (out) {
+        /* backspace */
       case 0x7F:
         if (sz > 0) {
-          msh_move_cursor(1);
+          msh_move_cursor(-1);
           msh_write(" ", 1);
-          msh_move_cursor(1);
+          msh_move_cursor(-1);
           buf[sz--] = '\0';
         }
-
         break;
         /* Ctrl-C */
       case 0x3:
         msh_print_string("^C\n\r");
         goto end_loop;
         break;
+      /* left */
+      case -3:
+        if (sz > 0) {
+          msh_move_cursor(-1);
+          --sz;
+          ++leftoff;
+        }
+        break;
+      /* right */
+      case -4:
+        if (leftoff > 0) {
+          msh_move_cursor(1);
+          --leftoff;
+        }
+        if (sz < 2048) {
+          ++sz;
+        }
+        break;
+      default:
+        if (leftoff > 0) {
+          --leftoff;
+        }
+        break;
       }
     }
 
+    sz += leftoff;
+    buf[sz] = '\0';
+
     if (*buf != '\0') {
       msh_lexer_parse(lexer, buf, sz + 1);
       msh_lexer_execute(lexer);

src/system/linux/linux.c

@@ -25,13 +25,23 @@ int msh_read_input(char *ptr, SIZE_TYPE *size, SIZE_TYPE n) {
       *size += sz;
     } else {
       switch (ch) {
+        /* left/right arrow */
+      case '\033':
+        SYSCALL(read, 0, &ch, 1);
+        if (ch == '[') {
+          SYSCALL(read, 0, &ch, 1);
+          switch (ch) {
+          case 'C':
+            return -4;
+          case 'D':
+            return -3;
+          }
+        }
+        break;
         /* return */
       case '\r':
-        ptr[*size] = '\0';
         SYSCALL(write, 1, "\n\r", 2);
         return -1;
-        break;
-        /* backspace */
       default:
         break;
       }
@@ -47,10 +57,10 @@ int msh_read_input(char *ptr, SIZE_TYPE *size, SIZE_TYPE n) {
 
 void msh_move_cursor(signed int offset) {
   int i;
-  char *cmd = "\33[D";
-  if (offset <= 0) {
-    offset &= ~0xffffffff;
-    cmd = "\33[C";
+  char *cmd = "\33[C";
+  if (offset < 0) {
+    offset *= -1;
+    cmd = "\33[D";
   }
   for (i = 0; i < offset; i++) {
     SYSCALL(write, 1, cmd, 3);

src/system/system.h

@@ -60,8 +60,12 @@ void msh_file_read(msh_file *file, char *ptr, SIZE_TYPE n);
 /*
  * Read user input into ptr, stopping if it has reached n characters.
  * RETURNS:
- * * -2 = if it ran out of space.
  * * -1 = if finished reading
+ * * -2 = if it ran out of space.
+ * * -3 = left arrow
+ * * -4 = right arrow
+ * * -5 = ctrl left arrow
+ * * -6 = ctrl right arrow
  * *  0 < ascii character
  */
 int msh_read_input(char *ptr, SIZE_TYPE *size, SIZE_TYPE n);