Merge pull request #104 from ArsenArsen/trunk

readline: re-add emacs key support

stage23/lib/readline.c

@@ -4,13 +4,14 @@
 #include <lib/libc.h>
 #include <lib/blib.h>
 #include <lib/term.h>
+#include <lib/print.h>
 #if bios == 1
 #  include <lib/real.h>
 #elif uefi == 1
 #  include <efi.h>
 #endif
 
-int getchar_internal(uint8_t scancode, uint8_t ascii) {
+int getchar_internal(uint8_t scancode, uint8_t ascii, uint32_t shift_state) {
     switch (scancode) {
 #if bios == 1
         case 0x44:
@@ -66,6 +67,17 @@ int getchar_internal(uint8_t scancode, uint8_t ascii) {
         case '\b':
             return '\b';
     }
+
+    if (shift_state & (GETCHAR_LCTRL | GETCHAR_RCTRL)) {
+        switch (ascii) {
+        case 'p': return GETCHAR_CURSOR_UP;
+        case 'n': return GETCHAR_CURSOR_DOWN;
+        case 'b': return GETCHAR_CURSOR_LEFT;
+        case 'f': return GETCHAR_CURSOR_RIGHT;
+        default: break;
+        }
+    }
+
     // Guard against non-printable values
     if (ascii < 0x20 || ascii > 0x7e) {
         return -1;
@@ -75,10 +87,26 @@ int getchar_internal(uint8_t scancode, uint8_t ascii) {
 
 #if bios == 1
 int getchar(void) {
+    uint8_t scancode = 0;
+    uint8_t ascii = 0;
+    uint32_t mods = 0;
 again:;
     struct rm_regs r = {0};
     rm_int(0x16, &r, &r);
-    int ret = getchar_internal((r.eax >> 8) & 0xff, r.eax);
+    scancode = (r.eax >> 8) & 0xff;
+    ascii = r.eax & 0xff;
+
+    r = (struct rm_regs){ 0 };
+    r.eax = 0x0200; // GET SHIFT FLAGS
+    rm_int(0x16, &r, &r);
+
+    if (r.eax & GETCHAR_LCTRL) {
+        /* the bios subtracts 0x60 from ascii if ctrl is pressed */
+        mods = GETCHAR_LCTRL;
+        ascii += 0x60;
+    }
+
+    int ret = getchar_internal(scancode, ascii, mods);
     if (ret == -1)
         goto again;
     return ret;
@@ -92,26 +120,67 @@ int pit_sleep_and_quit_on_keypress(int seconds) {
 #endif
 
 #if uefi == 1
+static EFI_KEY_DATA _read_efi_key(EFI_HANDLE device) {
+    EFI_KEY_DATA out = {
+        /* default to no modifiers */
+        .KeyState = { 0 },
+    };
+
+    EFI_GUID exproto_guid = EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL_GUID;
+    EFI_GUID sproto_guid = EFI_SIMPLE_TEXT_INPUT_PROTOCOL_GUID;
+    EFI_SIMPLE_TEXT_INPUT_EX_PROTOCOL *exproto = NULL;
+    EFI_SIMPLE_TEXT_IN_PROTOCOL *sproto = NULL;
+
+    if (gBS->HandleProtocol(device, &exproto_guid, (void **)&exproto) != EFI_SUCCESS) {
+        if (gBS->HandleProtocol(device, &sproto_guid, (void **)&sproto)
+            != EFI_SUCCESS) {
+            panic("Your input device doesn't have an input protocol!");
+        }
+    }
+
+    EFI_STATUS status = EFI_UNSUPPORTED;
+    if (exproto) {
+        status = exproto->ReadKeyStrokeEx(exproto, &out);
+    } else {
+        status = sproto->ReadKeyStroke(sproto, &out.Key);
+    }
+
+    /* there is definitely a key pending here, if there isn't, there's
+     * something very wrong, as the caller should be waiting on a key.
+     */
+    if (status != EFI_SUCCESS) {
+        panic("Failed to read from the keyboard");
+    }
+
+    if (!(out.KeyState.KeyShiftState & EFI_SHIFT_STATE_VALID)) {
+        out.KeyState.KeyShiftState = 0;
+    }
+
+    return out;
+}
+
 int getchar(void) {
 again:;
-    EFI_INPUT_KEY key = {0};
+    EFI_KEY_DATA kd;
 
     UINTN which;
 
     gBS->WaitForEvent(1, (EFI_EVENT[]){ gST->ConIn->WaitForKey }, &which);
 
-    gST->ConIn->ReadKeyStroke(gST->ConIn, &key);
+    kd = _read_efi_key(gST->ConsoleInHandle);
 
-    int ret = getchar_internal(key.ScanCode, key.UnicodeChar);
+    int ret = getchar_internal(kd.Key.ScanCode, kd.Key.UnicodeChar,
+                               kd.KeyState.KeyShiftState);
 
-    if (ret == -1)
+    if (ret == -1) {
         goto again;
+    }
 
     return ret;
 }
 
 int pit_sleep_and_quit_on_keypress(int seconds) {
-    EFI_INPUT_KEY key = {0};
+    EFI_KEY_DATA kd;
 
     UINTN which;
 
@@ -130,12 +199,14 @@ again:
         return 0;
     }
 
-    gST->ConIn->ReadKeyStroke(gST->ConIn, &key);
+    kd = _read_efi_key(gST->ConsoleInHandle);
 
-    int ret = getchar_internal(key.ScanCode, key.UnicodeChar);
+    int ret = getchar_internal(kd.Key.ScanCode, kd.Key.UnicodeChar,
+                               kd.KeyState.KeyShiftState);
 
-    if (ret == -1)
+    if (ret == -1) {
         goto again;
+    }
 
     return ret;
 }

stage23/lib/readline.h

@@ -15,6 +15,14 @@
 #define GETCHAR_F10          (-19)
 #define GETCHAR_ESCAPE       (-20)
 
+#if bios == 1
+#   define GETCHAR_RCTRL 0x4
+#   define GETCHAR_LCTRL GETCHAR_RCTRL
+#elif uefi == 1
+#   define GETCHAR_RCTRL EFI_RIGHT_CONTROL_PRESSED
+#   define GETCHAR_LCTRL EFI_LEFT_CONTROL_PRESSED
+#endif
+
 int getchar(void);
 void readline(const char *orig_str, char *buf, size_t limit);