termio: get rid of manual backend

src/termio/Termio.zig

@@ -256,9 +256,7 @@ pub fn threadEnter(self: *Termio, thread: *termio.Thread, data: *ThreadData) !vo
         .renderer_state = self.renderer_state,
         .surface_mailbox = self.surface_mailbox,
         .mailbox = &self.mailbox,
-
-        // Placeholder until setup below
-        .backend = .{ .manual = {} },
+        .backend = undefined, // Backend must replace this on threadEnter
     };
 
     // Setup our backend

src/termio/backend.zig

@@ -19,17 +19,11 @@ const Pty = @import("../pty.zig").Pty;
 // enough to satisfy most write requests. It must be a power of 2.
 const WRITE_REQ_PREALLOC = std.math.pow(usize, 2, 5);
 
-/// The kinds of readers.
-pub const Kind = enum { manual, exec };
+/// The kinds of backends.
+pub const Kind = enum { exec };
 
-/// Configuration for the various reader types.
+/// Configuration for the various backend types.
 pub const Config = union(Kind) {
-    /// Manual means that the termio caller will handle reading input
-    /// and passing it to the termio implementation. Note that even if you
-    /// select a different reader, you can always still manually provide input;
-    /// this config just makes it so that it is ONLY manual input.
-    manual: void,
-
     /// Exec uses posix exec to run a command with a pty.
     exec: termio.Exec.Config,
 };
@@ -37,19 +31,16 @@ pub const Config = union(Kind) {
 /// Backend implementations. A backend is responsible for owning the pty
 /// behavior and providing read/write capabilities.
 pub const Backend = union(Kind) {
-    manual: void,
     exec: termio.Exec,
 
     pub fn deinit(self: *Backend) void {
         switch (self.*) {
-            .manual => {},
             .exec => |*exec| exec.deinit(),
         }
     }
 
     pub fn initTerminal(self: *Backend, t: *terminal.Terminal) void {
         switch (self.*) {
-            .manual => {},
             .exec => |*exec| exec.initTerminal(t),
         }
     }
@@ -61,14 +52,12 @@ pub const Backend = union(Kind) {
         td: *termio.Termio.ThreadData,
     ) !void {
         switch (self.*) {
-            .manual => {},
             .exec => |*exec| try exec.threadEnter(alloc, io, td),
         }
     }
 
     pub fn threadExit(self: *Backend, td: *termio.Termio.ThreadData) void {
         switch (self.*) {
-            .manual => {},
             .exec => |*exec| exec.threadExit(td),
         }
     }
@@ -79,7 +68,6 @@ pub const Backend = union(Kind) {
         screen_size: renderer.ScreenSize,
     ) !void {
         switch (self.*) {
-            .manual => {},
             .exec => |*exec| try exec.resize(grid_size, screen_size),
         }
     }
@@ -92,7 +80,6 @@ pub const Backend = union(Kind) {
         linefeed: bool,
     ) !void {
         switch (self.*) {
-            .manual => {},
             .exec => |*exec| try exec.queueWrite(alloc, td, data, linefeed),
         }
     }
@@ -105,7 +92,6 @@ pub const Backend = union(Kind) {
         runtime_ms: u64,
     ) !void {
         switch (self.*) {
-            .manual => {},
             .exec => |*exec| try exec.childExitedAbnormally(
                 gpa,
                 t,
@@ -118,19 +104,16 @@ pub const Backend = union(Kind) {
 
 /// Termio thread data. See termio.ThreadData for docs.
 pub const ThreadData = union(Kind) {
-    manual: void,
     exec: termio.Exec.ThreadData,
 
     pub fn deinit(self: *ThreadData, alloc: Allocator) void {
         switch (self.*) {
-            .manual => {},
             .exec => |*exec| exec.deinit(alloc),
         }
     }
 
     pub fn changeConfig(self: *ThreadData, config: *termio.DerivedConfig) void {
         switch (self.*) {
-            .manual => {},
             .exec => |*exec| {
                 exec.abnormal_runtime_threshold_ms = config.abnormal_runtime_threshold_ms;
                 exec.wait_after_command = config.wait_after_command;