Refactor termios stuff in unix console

python · ambv · May 5, 2024 · Oct 20, 2023 · Apr 27, 2024 · Apr 27, 2024
commit 2a7e81d3d772a23fe9803526916a56eb4fe0788b
@@ -17,9 +17,14 @@
 # CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
 # CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 
+import curses
 import termios
 
 
+class InvalidTerminal(RuntimeError):
+    pass
+
+
 class TermState:
     def __init__(self, tuples):
         (
@@ -55,20 +60,212 @@ def tcsetattr(fd, when, attrs):
     termios.tcsetattr(fd, when, attrs.as_list())
 
 
-class Term(TermState):
-    TS__init__ = TermState.__init__
+class TermCapability:
+    """Base class for all terminal capabilities we need"""
+
+    def __init__(self, buffer):
+        self._buffer = buffer
+        self._args = []
+
+        self._bytes = curses.tigetstr(self.name)
+        if self._bytes is None and not self.optional:
+            raise InvalidTerminal(
+                f"terminal doesn't have the required {self.name!r} capability"
+            )
+
+        self.supported = self._bytes is not None
+
+    def __call__(self, *args):
+        if self.supported:
+            self._args = args
+            self._buffer.push(self)
+
+    def text(self):
+        return curses.tparm(self._bytes, *self._args)
+
+
+class Bell(TermCapability):
+    """Audible signal (bell)"""
+
+    name = "bel"
+    optional = False
+
+
+class CursorInvisible(TermCapability):
+    """Make cursor invisible"""
+
+    name = "civis"
+    optional = True
+
+
+class ClearScreen(TermCapability):
+    """Clear screen and home cursor"""
+
+    name = "clear"
+    optional = False
+
+
+class CursorNormal(TermCapability):
+    """Make cursor appear normal (undo civis/cvvis)"""
+
+    name = "cnorm"
+    optional = True
+
+
+class ParmLeftCursor(TermCapability):
+    """Move #1 characters to the left"""
+
+    name = "cub"
+    optional = True
+
+
+class CursorLeft(TermCapability):
+    """Move left one space"""
+
+    name = "cub1"
+    optional = True
+
+    def text(self):
+        assert len(self._args) == 1  # cursor_down needs to have been called with dx
+        return curses.tparm(self._args[0] * self._bytes)
+
+
+class ParmDownCursor(TermCapability):
+    """Down #1 lines"""
+
+    name = "cud"
+    optional = True
+
+
+class CursorDown(TermCapability):
+    """Down one line"""
+
+    name = "cud1"
+    optional = True
+
+    def text(self):
+        assert len(self._args) == 1  # cursor_down needs to have been called with dy
+        return curses.tparm(self._args[0] * self._bytes)
+
+
+class ParmRightCursor(TermCapability):
+    """Move #1 characters to the right"""
+
+    name = "cuf"
+    optional = True
+
+
+class CursorRight(TermCapability):
+    """Non-destructive space (move right one space)"""
+
+    name = "cuf1"
+    optional = True
+
+    def text(self):
+        assert len(self._args) == 1  # cursor_down needs to have been called with dx
+        return curses.tparm(self._args[0] * self._bytes)
+
+
+class CursorAddress(TermCapability):
+    """Move to row #1 columns #2"""
+
+    name = "cup"
+    optional = False
+
+
+class ParmUpCursor(TermCapability):
+    """Up #1 lines"""
+
+    name = "cuu"
+    optional = True
+
+
+class CursorUp(TermCapability):
+    """Up 1 line"""
+
+    name = "cuu1"
+    optional = True
+
+    def text(self):
+        assert len(self._args) == 1  # cursor_down needs to have been called with dy
+        return curses.tparm(self._args[0] * self._bytes)
+
+
+class ParmDeleteCharacter(TermCapability):
+    """Delete #1 characters"""
+
+    name = "dch"
+    optional = True
+
+
+class DeleteCharacter(TermCapability):
+    """Delete character"""
+
+    name = "dch1"
+    optional = True
+
+
+class ClearEol(TermCapability):
+    """Clear to end of line"""
+
+    name = "el"
+    optional = False
+
+
+class ColumnAddress(TermCapability):
+    """Horizontal position #1, absolute"""
+
+    name = "hpa"
+    optional = True
+
+
+class ParmInsertCharacter(TermCapability):
+    """Insert #1 characters"""
+
+    name = "ich"
+    optional = True
+
+
+class InsertCharacter(TermCapability):
+    """Insert character"""
+
+    name = "ich1"
+    optional = True
+
+
+class ScrollForward(TermCapability):
+    """Scroll text up"""
+
+    name = "ind"
+    optional = True
+
+
+class PadChar(TermCapability):
+    """Padding char (instead of null)"""
+
+    name = "pad"
+    optional = True
+
+    def text(self, nchars):
+        return self._bytes * nchars
+
+
+class ScrollReverse(TermCapability):
+    """Scroll text down"""
+
+    name = "ri"
+    optional = True
+
+
+class KeypadLocal(TermCapability):
+    """Leave 'keyboard_transmit' mode"""
 
-    def __init__(self, fd=0):
-        self.TS__init__(termios.tcgetattr(fd))
-        self.fd = fd
-        self.stack = []
+    name = "rmkx"
+    optional = True
 
-    def save(self):
-        self.stack.append(self.as_list())
 
-    def set(self, when=termios.TCSANOW):
-        termios.tcsetattr(self.fd, when, self.as_list())
+class KeypadXmit(TermCapability):
+    """Enter 'keyboard_transmit' mode"""
 
-    def restore(self):
-        self.TS__init__(self.stack.pop())
-        self.set()
+    name = "smkx"
+    optional = True