chore: upgrade libghostty and preserve terminal behavior (#3906)

1 files changed, 366 insertions, 165 deletions

diff --git a/vendor/libghostty-vt/src/lib_vt.zig b/vendor/libghostty-vt/src/lib_vt.zig
index e01cdbb8..a0227aef 100644
--- a/vendor/libghostty-vt/src/lib_vt.zig
+++ b/vendor/libghostty-vt/src/lib_vt.zig
@@ -11,6 +11,7 @@ const lib = @This();
 
 const std = @import("std");
 const builtin = @import("builtin");
+const stderr = @import("os/stderr.zig");
 
 // The public API below reproduces a lot of terminal/main.zig but
 // is separate because (1) we need our root file to be in `src/`
@@ -37,7 +38,20 @@ const terminal = @import("terminal/main.zig");
 /// Additional functionality will be added here over time as needed.
 pub const sys = terminal.sys;
 
+/// A tiny, blocking `std.Io` implementation optimized for binary size.
+///
+/// Constructing a `Terminal` requires a `std.Io` for features that touch
+/// the filesystem (e.g. Kitty graphics file transmission). Embedders that
+/// don't have their own `Io` can use `TinyIo` (e.g.
+/// `(TinyIo.init).io()`) instead of `std.Io.Threaded` to avoid linking
+/// Threaded's full vtable (networking, process spawning, async
+/// machinery, etc.), which is worth roughly 110KB of binary size on
+/// macOS and 370KB on Windows. See the TinyIo docs for the exact
+/// tradeoffs.
+pub const TinyIo = @import("lib/TinyIo.zig");
+
 pub const apc = terminal.apc;
+pub const clipboard = terminal.clipboard;
 pub const dcs = terminal.dcs;
 pub const osc = terminal.osc;
 pub const point = terminal.point;
@@ -52,6 +66,7 @@ pub const parse_table = terminal.parse_table;
 pub const search = terminal.search;
 pub const sgr = terminal.sgr;
 pub const size = terminal.size;
+pub const snapshot = terminal.snapshot;
 pub const x11_color = terminal.x11_color;
 
 pub const Charset = terminal.Charset;
@@ -80,6 +95,11 @@ pub const Terminal = terminal.Terminal;
 pub const TerminalStream = terminal.TerminalStream;
 pub const Stream = terminal.Stream;
 pub const StreamAction = terminal.StreamAction;
+pub const UnknownSequence = terminal.UnknownSequence;
+
+pub const Paste = terminal.Paste;
+pub const PasteSource = terminal.PasteSource;
+pub const PasteError = terminal.PasteError;
 pub const Cursor = Screen.Cursor;
 pub const CursorStyle = Screen.CursorStyle;
 pub const CursorStyleReq = terminal.CursorStyle;
@@ -114,8 +134,11 @@ pub const input = struct {
     // Paste-related APIs
     pub const PasteError = paste.Error;
     pub const PasteOptions = paste.Options;
+    pub const max_paste_frame_size = paste.max_frame_size;
     pub const isSafePaste = paste.isSafe;
+    pub const isSafePasteWith = paste.isSafeWith;
     pub const encodePaste = paste.encode;
+    pub const encodePasteWriter = paste.encodeWriter;
 
     // Key encoding
     pub const Key = key.Key;
@@ -141,49 +164,77 @@ pub const unicode = struct {
     pub const graphemeWidth = unicode_pkg.graphemeWidth;
 };
 
+/// Used for MSVC builds (see below)
+var msvc_fltused: c_int = 1;
+
 comptime {
     // If we're building the C library (vs. the Zig module) then
     // we want to reference the C API so that it gets exported.
     if (@import("root") == lib) {
+        // MSVC requires this marker whenever floating-point code is present.
+        // Zig's compiler_rt only provides it when libc is not linked.
+        if (builtin.os.tag == .windows and
+            builtin.abi == .msvc and
+            builtin.link_mode == .static)
+        {
+            @export(
+                &msvc_fltused,
+                .{ .name = "_fltused" },
+            );
+        }
+
+        // Force-reference our memset override so its export is
+        // emitted. This must stay inside the root guard so that
+        // downstream Zig module consumers don't get the override
+        // injected into their binaries. See quirks_memset.zig.
+        _ = @import("quirks_memset.zig");
+
         const c = terminal.c_api;
-        @export(&c.key_event_new, .{ .name = "ghostty_key_event_new" });
-        @export(&c.key_event_free, .{ .name = "ghostty_key_event_free" });
-        @export(&c.key_event_set_action, .{ .name = "ghostty_key_event_set_action" });
-        @export(&c.key_event_get_action, .{ .name = "ghostty_key_event_get_action" });
-        @export(&c.key_event_set_key, .{ .name = "ghostty_key_event_set_key" });
-        @export(&c.key_event_get_key, .{ .name = "ghostty_key_event_get_key" });
-        @export(&c.key_event_set_mods, .{ .name = "ghostty_key_event_set_mods" });
-        @export(&c.key_event_get_mods, .{ .name = "ghostty_key_event_get_mods" });
-        @export(&c.key_event_set_consumed_mods, .{ .name = "ghostty_key_event_set_consumed_mods" });
-        @export(&c.key_event_get_consumed_mods, .{ .name = "ghostty_key_event_get_consumed_mods" });
-        @export(&c.key_event_set_composing, .{ .name = "ghostty_key_event_set_composing" });
-        @export(&c.key_event_get_composing, .{ .name = "ghostty_key_event_get_composing" });
-        @export(&c.key_event_set_utf8, .{ .name = "ghostty_key_event_set_utf8" });
-        @export(&c.key_event_get_utf8, .{ .name = "ghostty_key_event_get_utf8" });
-        @export(&c.key_event_set_unshifted_codepoint, .{ .name = "ghostty_key_event_set_unshifted_codepoint" });
-        @export(&c.key_event_get_unshifted_codepoint, .{ .name = "ghostty_key_event_get_unshifted_codepoint" });
-        @export(&c.key_encoder_new, .{ .name = "ghostty_key_encoder_new" });
-        @export(&c.key_encoder_free, .{ .name = "ghostty_key_encoder_free" });
-        @export(&c.key_encoder_setopt, .{ .name = "ghostty_key_encoder_setopt" });
-        @export(&c.key_encoder_setopt_from_terminal, .{ .name = "ghostty_key_encoder_setopt_from_terminal" });
-        @export(&c.key_encoder_encode, .{ .name = "ghostty_key_encoder_encode" });
-        @export(&c.mouse_event_new, .{ .name = "ghostty_mouse_event_new" });
-        @export(&c.mouse_event_free, .{ .name = "ghostty_mouse_event_free" });
-        @export(&c.mouse_event_set_action, .{ .name = "ghostty_mouse_event_set_action" });
-        @export(&c.mouse_event_get_action, .{ .name = "ghostty_mouse_event_get_action" });
-        @export(&c.mouse_event_set_button, .{ .name = "ghostty_mouse_event_set_button" });
-        @export(&c.mouse_event_clear_button, .{ .name = "ghostty_mouse_event_clear_button" });
-        @export(&c.mouse_event_get_button, .{ .name = "ghostty_mouse_event_get_button" });
-        @export(&c.mouse_event_set_mods, .{ .name = "ghostty_mouse_event_set_mods" });
-        @export(&c.mouse_event_get_mods, .{ .name = "ghostty_mouse_event_get_mods" });
-        @export(&c.mouse_event_set_position, .{ .name = "ghostty_mouse_event_set_position" });
-        @export(&c.mouse_event_get_position, .{ .name = "ghostty_mouse_event_get_position" });
-        @export(&c.mouse_encoder_new, .{ .name = "ghostty_mouse_encoder_new" });
-        @export(&c.mouse_encoder_free, .{ .name = "ghostty_mouse_encoder_free" });
-        @export(&c.mouse_encoder_setopt, .{ .name = "ghostty_mouse_encoder_setopt" });
-        @export(&c.mouse_encoder_setopt_from_terminal, .{ .name = "ghostty_mouse_encoder_setopt_from_terminal" });
-        @export(&c.mouse_encoder_reset, .{ .name = "ghostty_mouse_encoder_reset" });
-        @export(&c.mouse_encoder_encode, .{ .name = "ghostty_mouse_encoder_encode" });
+        const features = terminal.options;
+        if (features.input_encode) {
+            @export(&c.key_event_new, .{ .name = "ghostty_key_event_new" });
+            @export(&c.key_event_free, .{ .name = "ghostty_key_event_free" });
+            @export(&c.key_event_set_action, .{ .name = "ghostty_key_event_set_action" });
+            @export(&c.key_event_get_action, .{ .name = "ghostty_key_event_get_action" });
+            @export(&c.key_event_set_key, .{ .name = "ghostty_key_event_set_key" });
+            @export(&c.key_event_get_key, .{ .name = "ghostty_key_event_get_key" });
+            @export(&c.key_event_set_mods, .{ .name = "ghostty_key_event_set_mods" });
+            @export(&c.key_event_get_mods, .{ .name = "ghostty_key_event_get_mods" });
+            @export(&c.key_event_set_consumed_mods, .{ .name = "ghostty_key_event_set_consumed_mods" });
+            @export(&c.key_event_get_consumed_mods, .{ .name = "ghostty_key_event_get_consumed_mods" });
+            @export(&c.key_event_set_composing, .{ .name = "ghostty_key_event_set_composing" });
+            @export(&c.key_event_get_composing, .{ .name = "ghostty_key_event_get_composing" });
+            @export(&c.key_event_set_utf8, .{ .name = "ghostty_key_event_set_utf8" });
+            @export(&c.key_event_get_utf8, .{ .name = "ghostty_key_event_get_utf8" });
+            @export(&c.key_event_set_unshifted_codepoint, .{ .name = "ghostty_key_event_set_unshifted_codepoint" });
+            @export(&c.key_event_get_unshifted_codepoint, .{ .name = "ghostty_key_event_get_unshifted_codepoint" });
+            @export(&c.key_encoder_new, .{ .name = "ghostty_key_encoder_new" });
+            @export(&c.key_encoder_free, .{ .name = "ghostty_key_encoder_free" });
+            @export(&c.key_encoder_setopt, .{ .name = "ghostty_key_encoder_setopt" });
+            @export(&c.key_encoder_setopt_from_terminal, .{ .name = "ghostty_key_encoder_setopt_from_terminal" });
+            @export(&c.key_encoder_encode, .{ .name = "ghostty_key_encoder_encode" });
+            @export(&c.focus_encode, .{ .name = "ghostty_focus_encode" });
+            @export(&c.paste_is_safe, .{ .name = "ghostty_paste_is_safe" });
+            @export(&c.paste_encode, .{ .name = "ghostty_paste_encode" });
+            @export(&c.terminal_paste, .{ .name = "ghostty_terminal_paste" });
+            @export(&c.mouse_event_new, .{ .name = "ghostty_mouse_event_new" });
+            @export(&c.mouse_event_free, .{ .name = "ghostty_mouse_event_free" });
+            @export(&c.mouse_event_set_action, .{ .name = "ghostty_mouse_event_set_action" });
+            @export(&c.mouse_event_get_action, .{ .name = "ghostty_mouse_event_get_action" });
+            @export(&c.mouse_event_set_button, .{ .name = "ghostty_mouse_event_set_button" });
+            @export(&c.mouse_event_clear_button, .{ .name = "ghostty_mouse_event_clear_button" });
+            @export(&c.mouse_event_get_button, .{ .name = "ghostty_mouse_event_get_button" });
+            @export(&c.mouse_event_set_mods, .{ .name = "ghostty_mouse_event_set_mods" });
+            @export(&c.mouse_event_get_mods, .{ .name = "ghostty_mouse_event_get_mods" });
+            @export(&c.mouse_event_set_position, .{ .name = "ghostty_mouse_event_set_position" });
+            @export(&c.mouse_event_get_position, .{ .name = "ghostty_mouse_event_get_position" });
+            @export(&c.mouse_encoder_new, .{ .name = "ghostty_mouse_encoder_new" });
+            @export(&c.mouse_encoder_free, .{ .name = "ghostty_mouse_encoder_free" });
+            @export(&c.mouse_encoder_setopt, .{ .name = "ghostty_mouse_encoder_setopt" });
+            @export(&c.mouse_encoder_setopt_from_terminal, .{ .name = "ghostty_mouse_encoder_setopt_from_terminal" });
+            @export(&c.mouse_encoder_reset, .{ .name = "ghostty_mouse_encoder_reset" });
+            @export(&c.mouse_encoder_encode, .{ .name = "ghostty_mouse_encoder_encode" });
+        }
         @export(&c.osc_new, .{ .name = "ghostty_osc_new" });
         @export(&c.osc_free, .{ .name = "ghostty_osc_free" });
         @export(&c.osc_next, .{ .name = "ghostty_osc_next" });
@@ -192,10 +243,7 @@ comptime {
         @export(&c.osc_command_type, .{ .name = "ghostty_osc_command_type" });
         @export(&c.osc_command_data, .{ .name = "ghostty_osc_command_data" });
         @export(&c.color_scheme_report_encode, .{ .name = "ghostty_color_scheme_report_encode" });
-        @export(&c.focus_encode, .{ .name = "ghostty_focus_encode" });
         @export(&c.mode_report_encode, .{ .name = "ghostty_mode_report_encode" });
-        @export(&c.paste_is_safe, .{ .name = "ghostty_paste_is_safe" });
-        @export(&c.paste_encode, .{ .name = "ghostty_paste_encode" });
         @export(&c.unicode_codepoint_width, .{ .name = "ghostty_unicode_codepoint_width" });
         @export(&c.unicode_grapheme_width, .{ .name = "ghostty_unicode_grapheme_width" });
         @export(&c.size_report_encode, .{ .name = "ghostty_size_report_encode" });
@@ -203,21 +251,25 @@ comptime {
         @export(&c.style_is_default, .{ .name = "ghostty_style_is_default" });
         @export(&c.sys_log_stderr, .{ .name = "ghostty_sys_log_stderr" });
         @export(&c.sys_set, .{ .name = "ghostty_sys_set" });
-        @export(&c.cell_get, .{ .name = "ghostty_cell_get" });
-        @export(&c.cell_get_multi, .{ .name = "ghostty_cell_get_multi" });
-        @export(&c.row_get, .{ .name = "ghostty_row_get" });
-        @export(&c.row_get_multi, .{ .name = "ghostty_row_get_multi" });
-        @export(&c.color_rgb_get, .{ .name = "ghostty_color_rgb_get" });
-        @export(&c.color_contrast, .{ .name = "ghostty_color_contrast" });
-        @export(&c.color_luminance, .{ .name = "ghostty_color_luminance" });
-        @export(&c.color_parse, .{ .name = "ghostty_color_parse" });
-        @export(&c.color_parse_palette_entry, .{ .name = "ghostty_color_parse_palette_entry" });
-        @export(&c.color_parse_x11, .{ .name = "ghostty_color_parse_x11" });
-        @export(&c.color_palette_default, .{ .name = "ghostty_color_palette_default" });
-        @export(&c.color_palette_generate, .{ .name = "ghostty_color_palette_generate" });
-        @export(&c.color_perceived_luminance, .{ .name = "ghostty_color_perceived_luminance" });
-        @export(&c.color_x11_name_count, .{ .name = "ghostty_color_x11_name_count" });
-        @export(&c.color_x11_names, .{ .name = "ghostty_color_x11_names" });
+        if (features.grid_introspection) {
+            @export(&c.cell_get, .{ .name = "ghostty_cell_get" });
+            @export(&c.cell_get_multi, .{ .name = "ghostty_cell_get_multi" });
+            @export(&c.row_get, .{ .name = "ghostty_row_get" });
+            @export(&c.row_get_multi, .{ .name = "ghostty_row_get_multi" });
+        }
+        if (features.color) {
+            @export(&c.color_rgb_get, .{ .name = "ghostty_color_rgb_get" });
+            @export(&c.color_contrast, .{ .name = "ghostty_color_contrast" });
+            @export(&c.color_luminance, .{ .name = "ghostty_color_luminance" });
+            @export(&c.color_parse, .{ .name = "ghostty_color_parse" });
+            @export(&c.color_parse_palette_entry, .{ .name = "ghostty_color_parse_palette_entry" });
+            @export(&c.color_parse_x11, .{ .name = "ghostty_color_parse_x11" });
+            @export(&c.color_palette_default, .{ .name = "ghostty_color_palette_default" });
+            @export(&c.color_palette_generate, .{ .name = "ghostty_color_palette_generate" });
+            @export(&c.color_perceived_luminance, .{ .name = "ghostty_color_perceived_luminance" });
+            @export(&c.color_x11_name_count, .{ .name = "ghostty_color_x11_name_count" });
+            @export(&c.color_x11_names, .{ .name = "ghostty_color_x11_names" });
+        }
         @export(&c.sgr_new, .{ .name = "ghostty_sgr_new" });
         @export(&c.sgr_free, .{ .name = "ghostty_sgr_free" });
         @export(&c.sgr_reset, .{ .name = "ghostty_sgr_reset" });
@@ -227,94 +279,142 @@ comptime {
         @export(&c.sgr_unknown_partial, .{ .name = "ghostty_sgr_unknown_partial" });
         @export(&c.sgr_attribute_tag, .{ .name = "ghostty_sgr_attribute_tag" });
         @export(&c.sgr_attribute_value, .{ .name = "ghostty_sgr_attribute_value" });
-        @export(&c.formatter_terminal_new, .{ .name = "ghostty_formatter_terminal_new" });
-        @export(&c.formatter_format_buf, .{ .name = "ghostty_formatter_format_buf" });
-        @export(&c.formatter_format_alloc, .{ .name = "ghostty_formatter_format_alloc" });
-        @export(&c.formatter_free, .{ .name = "ghostty_formatter_free" });
-        @export(&c.terminal_selection_format_buf, .{ .name = "ghostty_terminal_selection_format_buf" });
-        @export(&c.terminal_selection_format_alloc, .{ .name = "ghostty_terminal_selection_format_alloc" });
-        @export(&c.render_state_new, .{ .name = "ghostty_render_state_new" });
-        @export(&c.render_state_update, .{ .name = "ghostty_render_state_update" });
-        @export(&c.render_state_begin_update, .{ .name = "ghostty_render_state_begin_update" });
-        @export(&c.render_state_end_update, .{ .name = "ghostty_render_state_end_update" });
-        @export(&c.render_state_get, .{ .name = "ghostty_render_state_get" });
-        @export(&c.render_state_get_multi, .{ .name = "ghostty_render_state_get_multi" });
-        @export(&c.render_state_set, .{ .name = "ghostty_render_state_set" });
-        @export(&c.render_state_colors_get, .{ .name = "ghostty_render_state_colors_get" });
-        @export(&c.render_state_row_iterator_new, .{ .name = "ghostty_render_state_row_iterator_new" });
-        @export(&c.render_state_row_iterator_next, .{ .name = "ghostty_render_state_row_iterator_next" });
-        @export(&c.render_state_row_get, .{ .name = "ghostty_render_state_row_get" });
-        @export(&c.render_state_row_get_multi, .{ .name = "ghostty_render_state_row_get_multi" });
-        @export(&c.render_state_row_set, .{ .name = "ghostty_render_state_row_set" });
-        @export(&c.render_state_row_iterator_free, .{ .name = "ghostty_render_state_row_iterator_free" });
-        @export(&c.render_state_row_cells_new, .{ .name = "ghostty_render_state_row_cells_new" });
-        @export(&c.render_state_row_cells_next, .{ .name = "ghostty_render_state_row_cells_next" });
-        @export(&c.render_state_row_cells_select, .{ .name = "ghostty_render_state_row_cells_select" });
-        @export(&c.render_state_row_cells_get, .{ .name = "ghostty_render_state_row_cells_get" });
-        @export(&c.render_state_row_cells_get_multi, .{ .name = "ghostty_render_state_row_cells_get_multi" });
-        @export(&c.render_state_row_cells_free, .{ .name = "ghostty_render_state_row_cells_free" });
-        @export(&c.render_state_free, .{ .name = "ghostty_render_state_free" });
+        if (features.formatter) {
+            @export(&c.formatter_terminal_new, .{ .name = "ghostty_formatter_terminal_new" });
+            @export(&c.formatter_format, .{ .name = "ghostty_formatter_format" });
+            @export(&c.formatter_format_buf, .{ .name = "ghostty_formatter_format_buf" });
+            @export(&c.formatter_format_alloc, .{ .name = "ghostty_formatter_format_alloc" });
+            @export(&c.formatter_free, .{ .name = "ghostty_formatter_free" });
+        }
+        if (features.formatter and features.selection) {
+            @export(&c.terminal_selection_format_buf, .{ .name = "ghostty_terminal_selection_format_buf" });
+            @export(&c.terminal_selection_format_alloc, .{ .name = "ghostty_terminal_selection_format_alloc" });
+        }
+        if (features.render_state) {
+            @export(&c.render_state_new, .{ .name = "ghostty_render_state_new" });
+            @export(&c.render_state_update, .{ .name = "ghostty_render_state_update" });
+            @export(&c.render_state_begin_update, .{ .name = "ghostty_render_state_begin_update" });
+            @export(&c.render_state_end_update, .{ .name = "ghostty_render_state_end_update" });
+            @export(&c.render_state_clean, .{ .name = "ghostty_render_state_clean" });
+            @export(&c.render_state_get, .{ .name = "ghostty_render_state_get" });
+            @export(&c.render_state_get_multi, .{ .name = "ghostty_render_state_get_multi" });
+            @export(&c.render_state_set, .{ .name = "ghostty_render_state_set" });
+            @export(&c.render_state_row_iterator_new, .{ .name = "ghostty_render_state_row_iterator_new" });
+            @export(&c.render_state_row_iterator_next, .{ .name = "ghostty_render_state_row_iterator_next" });
+            @export(&c.render_state_row_iterator_next_dirty, .{ .name = "ghostty_render_state_row_iterator_next_dirty" });
+            @export(&c.render_state_row_get, .{ .name = "ghostty_render_state_row_get" });
+            @export(&c.render_state_row_get_multi, .{ .name = "ghostty_render_state_row_get_multi" });
+            @export(&c.render_state_row_set, .{ .name = "ghostty_render_state_row_set" });
+            @export(&c.render_state_row_iterator_free, .{ .name = "ghostty_render_state_row_iterator_free" });
+            @export(&c.render_state_row_cells_new, .{ .name = "ghostty_render_state_row_cells_new" });
+            @export(&c.render_state_row_cells_next, .{ .name = "ghostty_render_state_row_cells_next" });
+            @export(&c.render_state_row_cells_select, .{ .name = "ghostty_render_state_row_cells_select" });
+            @export(&c.render_state_row_cells_get, .{ .name = "ghostty_render_state_row_cells_get" });
+            @export(&c.render_state_row_cells_get_multi, .{ .name = "ghostty_render_state_row_cells_get_multi" });
+            @export(&c.render_state_row_cells_free, .{ .name = "ghostty_render_state_row_cells_free" });
+            @export(&c.render_state_free, .{ .name = "ghostty_render_state_free" });
+        }
         @export(&c.terminal_new, .{ .name = "ghostty_terminal_new" });
         @export(&c.terminal_free, .{ .name = "ghostty_terminal_free" });
         @export(&c.terminal_reset, .{ .name = "ghostty_terminal_reset" });
         @export(&c.terminal_resize, .{ .name = "ghostty_terminal_resize" });
         @export(&c.terminal_set, .{ .name = "ghostty_terminal_set" });
         @export(&c.terminal_vt_write, .{ .name = "ghostty_terminal_vt_write" });
+        @export(&c.terminal_vt_write_until_ground, .{ .name = "ghostty_terminal_vt_write_until_ground" });
         @export(&c.terminal_scroll_viewport, .{ .name = "ghostty_terminal_scroll_viewport" });
         @export(&c.terminal_compression_activity, .{ .name = "ghostty_terminal_compression_activity" });
         @export(&c.terminal_compress, .{ .name = "ghostty_terminal_compress" });
-        @export(&c.terminal_mode_get, .{ .name = "ghostty_terminal_mode_get" });
-        @export(&c.terminal_mode_set, .{ .name = "ghostty_terminal_mode_set" });
         @export(&c.terminal_get, .{ .name = "ghostty_terminal_get" });
         @export(&c.terminal_get_multi, .{ .name = "ghostty_terminal_get_multi" });
-        @export(&c.terminal_select_word, .{ .name = "ghostty_terminal_select_word" });
-        @export(&c.terminal_select_word_between, .{ .name = "ghostty_terminal_select_word_between" });
-        @export(&c.terminal_select_line, .{ .name = "ghostty_terminal_select_line" });
-        @export(&c.terminal_select_all, .{ .name = "ghostty_terminal_select_all" });
-        @export(&c.terminal_select_output, .{ .name = "ghostty_terminal_select_output" });
-        @export(&c.terminal_selection_adjust, .{ .name = "ghostty_terminal_selection_adjust" });
-        @export(&c.terminal_selection_order, .{ .name = "ghostty_terminal_selection_order" });
-        @export(&c.terminal_selection_ordered, .{ .name = "ghostty_terminal_selection_ordered" });
-        @export(&c.terminal_selection_contains, .{ .name = "ghostty_terminal_selection_contains" });
-        @export(&c.terminal_selection_equal, .{ .name = "ghostty_terminal_selection_equal" });
-        @export(&c.selection_gesture_new, .{ .name = "ghostty_selection_gesture_new" });
-        @export(&c.selection_gesture_free, .{ .name = "ghostty_selection_gesture_free" });
-        @export(&c.selection_gesture_reset, .{ .name = "ghostty_selection_gesture_reset" });
-        @export(&c.selection_gesture_event, .{ .name = "ghostty_selection_gesture_event" });
-        @export(&c.selection_gesture_get, .{ .name = "ghostty_selection_gesture_get" });
-        @export(&c.selection_gesture_get_multi, .{ .name = "ghostty_selection_gesture_get_multi" });
-        @export(&c.selection_gesture_event_new, .{ .name = "ghostty_selection_gesture_event_new" });
-        @export(&c.selection_gesture_event_free, .{ .name = "ghostty_selection_gesture_event_free" });
-        @export(&c.selection_gesture_event_set, .{ .name = "ghostty_selection_gesture_event_set" });
-        @export(&c.terminal_grid_ref, .{ .name = "ghostty_terminal_grid_ref" });
-        @export(&c.terminal_grid_ref_track, .{ .name = "ghostty_terminal_grid_ref_track" });
-        @export(&c.terminal_point_from_grid_ref, .{ .name = "ghostty_terminal_point_from_grid_ref" });
-        @export(&c.kitty_graphics_get, .{ .name = "ghostty_kitty_graphics_get" });
-        @export(&c.kitty_graphics_image, .{ .name = "ghostty_kitty_graphics_image" });
-        @export(&c.kitty_graphics_image_get, .{ .name = "ghostty_kitty_graphics_image_get" });
-        @export(&c.kitty_graphics_image_get_multi, .{ .name = "ghostty_kitty_graphics_image_get_multi" });
-        @export(&c.kitty_graphics_placement_iterator_new, .{ .name = "ghostty_kitty_graphics_placement_iterator_new" });
-        @export(&c.kitty_graphics_placement_iterator_free, .{ .name = "ghostty_kitty_graphics_placement_iterator_free" });
-        @export(&c.kitty_graphics_placement_iterator_set, .{ .name = "ghostty_kitty_graphics_placement_iterator_set" });
-        @export(&c.kitty_graphics_placement_next, .{ .name = "ghostty_kitty_graphics_placement_next" });
-        @export(&c.kitty_graphics_placement_get, .{ .name = "ghostty_kitty_graphics_placement_get" });
-        @export(&c.kitty_graphics_placement_get_multi, .{ .name = "ghostty_kitty_graphics_placement_get_multi" });
-        @export(&c.kitty_graphics_placement_rect, .{ .name = "ghostty_kitty_graphics_placement_rect" });
-        @export(&c.kitty_graphics_placement_pixel_size, .{ .name = "ghostty_kitty_graphics_placement_pixel_size" });
-        @export(&c.kitty_graphics_placement_grid_size, .{ .name = "ghostty_kitty_graphics_placement_grid_size" });
-        @export(&c.kitty_graphics_placement_viewport_pos, .{ .name = "ghostty_kitty_graphics_placement_viewport_pos" });
-        @export(&c.kitty_graphics_placement_source_rect, .{ .name = "ghostty_kitty_graphics_placement_source_rect" });
-        @export(&c.kitty_graphics_placement_render_info, .{ .name = "ghostty_kitty_graphics_placement_render_info" });
-        @export(&c.grid_ref_cell, .{ .name = "ghostty_grid_ref_cell" });
-        @export(&c.grid_ref_row, .{ .name = "ghostty_grid_ref_row" });
-        @export(&c.grid_ref_graphemes, .{ .name = "ghostty_grid_ref_graphemes" });
-        @export(&c.grid_ref_hyperlink_uri, .{ .name = "ghostty_grid_ref_hyperlink_uri" });
-        @export(&c.grid_ref_style, .{ .name = "ghostty_grid_ref_style" });
-        @export(&c.tracked_grid_ref_free, .{ .name = "ghostty_tracked_grid_ref_free" });
-        @export(&c.tracked_grid_ref_has_value, .{ .name = "ghostty_tracked_grid_ref_has_value" });
-        @export(&c.tracked_grid_ref_point, .{ .name = "ghostty_tracked_grid_ref_point" });
-        @export(&c.tracked_grid_ref_set, .{ .name = "ghostty_tracked_grid_ref_set" });
-        @export(&c.tracked_grid_ref_snapshot, .{ .name = "ghostty_tracked_grid_ref_snapshot" });
+        @export(&c.terminal_continuation_write, .{ .name = "ghostty_terminal_continuation_write" });
+        @export(&c.terminal_continuation_buf, .{ .name = "ghostty_terminal_continuation_buf" });
+        @export(&c.terminal_continuation_alloc, .{ .name = "ghostty_terminal_continuation_alloc" });
+        if (features.selection) {
+            @export(&c.terminal_select_word, .{ .name = "ghostty_terminal_select_word" });
+            @export(&c.terminal_select_word_between, .{ .name = "ghostty_terminal_select_word_between" });
+            @export(&c.terminal_select_line, .{ .name = "ghostty_terminal_select_line" });
+            @export(&c.terminal_select_all, .{ .name = "ghostty_terminal_select_all" });
+            @export(&c.terminal_select_output, .{ .name = "ghostty_terminal_select_output" });
+            @export(&c.terminal_selection_adjust, .{ .name = "ghostty_terminal_selection_adjust" });
+            @export(&c.terminal_selection_order, .{ .name = "ghostty_terminal_selection_order" });
+            @export(&c.terminal_selection_ordered, .{ .name = "ghostty_terminal_selection_ordered" });
+            @export(&c.terminal_selection_contains, .{ .name = "ghostty_terminal_selection_contains" });
+            @export(&c.terminal_selection_equal, .{ .name = "ghostty_terminal_selection_equal" });
+            @export(&c.selection_gesture_new, .{ .name = "ghostty_selection_gesture_new" });
+            @export(&c.selection_gesture_free, .{ .name = "ghostty_selection_gesture_free" });
+            @export(&c.selection_gesture_reset, .{ .name = "ghostty_selection_gesture_reset" });
+            @export(&c.selection_gesture_event, .{ .name = "ghostty_selection_gesture_event" });
+            @export(&c.selection_gesture_get, .{ .name = "ghostty_selection_gesture_get" });
+            @export(&c.selection_gesture_get_multi, .{ .name = "ghostty_selection_gesture_get_multi" });
+            @export(&c.selection_gesture_event_new, .{ .name = "ghostty_selection_gesture_event_new" });
+            @export(&c.selection_gesture_event_free, .{ .name = "ghostty_selection_gesture_event_free" });
+            @export(&c.selection_gesture_event_set, .{ .name = "ghostty_selection_gesture_event_set" });
+        }
+        if (features.search) {
+            @export(&c.search_new, .{ .name = "ghostty_search_new" });
+            @export(&c.search_free, .{ .name = "ghostty_search_free" });
+            @export(&c.search_tick, .{ .name = "ghostty_search_tick" });
+            @export(&c.search_feed, .{ .name = "ghostty_search_feed" });
+            @export(&c.search_run, .{ .name = "ghostty_search_run" });
+            @export(&c.search_set, .{ .name = "ghostty_search_set" });
+            @export(&c.search_get, .{ .name = "ghostty_search_get" });
+            @export(&c.search_get_multi, .{ .name = "ghostty_search_get_multi" });
+        }
+        // Selections are expressed in grid references, so the untracked
+        // reference constructors are required by both features.
+        if (features.grid_introspection or features.selection) {
+            @export(&c.terminal_grid_ref, .{ .name = "ghostty_terminal_grid_ref" });
+            @export(&c.terminal_point_from_grid_ref, .{ .name = "ghostty_terminal_point_from_grid_ref" });
+        }
+        if (features.grid_introspection) {
+            @export(&c.terminal_grid_ref_track, .{ .name = "ghostty_terminal_grid_ref_track" });
+        }
+        if (features.snapshot) {
+            @export(&c.snapshot_encode, .{ .name = "ghostty_snapshot_encode" });
+            @export(&c.snapshot_encode_buf, .{ .name = "ghostty_snapshot_encode_buf" });
+            @export(&c.snapshot_encode_alloc, .{ .name = "ghostty_snapshot_encode_alloc" });
+            @export(&c.snapshot_decoder_new, .{ .name = "ghostty_snapshot_decoder_new" });
+            @export(&c.snapshot_decoder_new_buf, .{ .name = "ghostty_snapshot_decoder_new_buf" });
+            @export(&c.snapshot_decoder_free, .{ .name = "ghostty_snapshot_decoder_free" });
+            @export(&c.snapshot_decoder_set, .{ .name = "ghostty_snapshot_decoder_set" });
+            @export(&c.snapshot_decoder_get, .{ .name = "ghostty_snapshot_decoder_get" });
+            @export(&c.snapshot_decoder_get_multi, .{ .name = "ghostty_snapshot_decoder_get_multi" });
+            @export(&c.snapshot_decoder_ready, .{ .name = "ghostty_snapshot_decoder_ready" });
+            @export(&c.snapshot_decoder_next, .{ .name = "ghostty_snapshot_decoder_next" });
+            @export(&c.snapshot_decoder_decode, .{ .name = "ghostty_snapshot_decoder_decode" });
+        }
+        if (features.kitty_graphics) {
+            @export(&c.kitty_graphics_get, .{ .name = "ghostty_kitty_graphics_get" });
+            @export(&c.kitty_graphics_image, .{ .name = "ghostty_kitty_graphics_image" });
+            @export(&c.kitty_graphics_image_get, .{ .name = "ghostty_kitty_graphics_image_get" });
+            @export(&c.kitty_graphics_image_get_multi, .{ .name = "ghostty_kitty_graphics_image_get_multi" });
+            @export(&c.kitty_graphics_placement_iterator_new, .{ .name = "ghostty_kitty_graphics_placement_iterator_new" });
+            @export(&c.kitty_graphics_placement_iterator_free, .{ .name = "ghostty_kitty_graphics_placement_iterator_free" });
+            @export(&c.kitty_graphics_placement_iterator_set, .{ .name = "ghostty_kitty_graphics_placement_iterator_set" });
+            @export(&c.kitty_graphics_placement_next, .{ .name = "ghostty_kitty_graphics_placement_next" });
+            @export(&c.kitty_graphics_placement_get, .{ .name = "ghostty_kitty_graphics_placement_get" });
+            @export(&c.kitty_graphics_placement_get_multi, .{ .name = "ghostty_kitty_graphics_placement_get_multi" });
+            @export(&c.kitty_graphics_placement_rect, .{ .name = "ghostty_kitty_graphics_placement_rect" });
+            @export(&c.kitty_graphics_placement_pixel_size, .{ .name = "ghostty_kitty_graphics_placement_pixel_size" });
+            @export(&c.kitty_graphics_placement_grid_size, .{ .name = "ghostty_kitty_graphics_placement_grid_size" });
+            @export(&c.kitty_graphics_placement_viewport_pos, .{ .name = "ghostty_kitty_graphics_placement_viewport_pos" });
+            @export(&c.kitty_graphics_placement_source_rect, .{ .name = "ghostty_kitty_graphics_placement_source_rect" });
+            @export(&c.kitty_graphics_placement_render_info, .{ .name = "ghostty_kitty_graphics_placement_render_info" });
+        }
+        if (features.grid_introspection) {
+            @export(&c.grid_ref_cell, .{ .name = "ghostty_grid_ref_cell" });
+            @export(&c.grid_ref_row, .{ .name = "ghostty_grid_ref_row" });
+            @export(&c.grid_ref_graphemes, .{ .name = "ghostty_grid_ref_graphemes" });
+            @export(&c.grid_ref_hyperlink_uri, .{ .name = "ghostty_grid_ref_hyperlink_uri" });
+            @export(&c.grid_ref_style, .{ .name = "ghostty_grid_ref_style" });
+            @export(&c.tracked_grid_ref_free, .{ .name = "ghostty_tracked_grid_ref_free" });
+            @export(&c.tracked_grid_ref_has_value, .{ .name = "ghostty_tracked_grid_ref_has_value" });
+            @export(&c.tracked_grid_ref_point, .{ .name = "ghostty_tracked_grid_ref_point" });
+            @export(&c.tracked_grid_ref_set, .{ .name = "ghostty_tracked_grid_ref_set" });
+        }
+        if (features.grid_introspection and features.snapshot) {
+            @export(&c.tracked_grid_ref_snapshot, .{ .name = "ghostty_tracked_grid_ref_snapshot" });
+        }
         @export(&c.build_info, .{ .name = "ghostty_build_info" });
         @export(&c.type_json, .{ .name = "ghostty_type_json" });
         @export(&c.alloc_alloc, .{ .name = "ghostty_alloc" });
@@ -322,47 +422,148 @@ comptime {
 
         // On Wasm we need to export our allocator convenience functions.
         if (builtin.target.cpu.arch.isWasm()) {
-            const alloc = @import("lib/allocator/convenience.zig");
+            const alloc = @import("lib/allocator/wasm.zig");
+            @export(&alloc.allocBytes, .{ .name = "ghostty_wasm_alloc" });
+            @export(&alloc.freeBytes, .{ .name = "ghostty_wasm_free" });
             @export(&alloc.allocOpaque, .{ .name = "ghostty_wasm_alloc_opaque" });
             @export(&alloc.freeOpaque, .{ .name = "ghostty_wasm_free_opaque" });
-            @export(&alloc.allocU8Array, .{ .name = "ghostty_wasm_alloc_u8_array" });
-            @export(&alloc.freeU8Array, .{ .name = "ghostty_wasm_free_u8_array" });
-            @export(&alloc.allocU16Array, .{ .name = "ghostty_wasm_alloc_u16_array" });
-            @export(&alloc.freeU16Array, .{ .name = "ghostty_wasm_free_u16_array" });
-            @export(&alloc.allocU8, .{ .name = "ghostty_wasm_alloc_u8" });
-            @export(&alloc.freeU8, .{ .name = "ghostty_wasm_free_u8" });
-            @export(&alloc.allocUsize, .{ .name = "ghostty_wasm_alloc_usize" });
-            @export(&alloc.freeUsize, .{ .name = "ghostty_wasm_free_usize" });
-            @export(&c.wasm_alloc_sgr_attribute, .{ .name = "ghostty_wasm_alloc_sgr_attribute" });
-            @export(&c.wasm_free_sgr_attribute, .{ .name = "ghostty_wasm_free_sgr_attribute" });
+            @export(&alloc.takeOpaque, .{ .name = "ghostty_wasm_take_opaque" });
         }
     }
 }
 
-pub const std_options: std.Options = options: {
-    if (builtin.target.cpu.arch.isWasm()) break :options .{
-        // Wasm builds we specifically want to optimize for space with small
-        // releases so we bump up to warn. Everything else acts pretty normal.
-        .log_level = switch (builtin.mode) {
-            .Debug => .debug,
-            .ReleaseSmall => .warn,
-            else => .info,
-        },
-
-        // Wasm doesn't have access to stdio so we have a custom log function.
-        .logFn = @import("os/wasm/log.zig").log,
-    };
-
-    // For C ABI builds, use a custom log function that dispatches to an
-    // embedder-provided callback (or silently discards when none is set).
-    if (terminal.options.c_abi) break :options .{
-        .logFn = @import("terminal/c/sys.zig").logFn,
-    };
-
-    break :options .{};
+pub const std_options: std.Options = opts: {
+    var options: std.Options = .{};
+
+    if (native_freestanding) {
+        // Freestanding targets don't have an OS page size. We still need an
+        // alignment for terminal page allocations, and 16 covers everything
+        // stored in a page without requiring 4 KiB-aligned embedded heaps.
+        options.page_size_min = 16;
+        options.page_size_max = 16;
+        options.allow_stack_tracing = false;
+    }
+
+    if (builtin.target.cpu.arch.isWasm()) {
+        // In non-debug modes, we want to ship effectively no logging
+        // warn and lower add ~200KB at the time of this comment.
+        if (builtin.mode == .Debug) {
+            options.log_level = .debug;
+            options.logFn = @import("os/wasm/log.zig").log;
+        } else {
+            options.log_level = .err;
+            options.logFn = @import("os/wasm/log.zig").noop;
+        }
+    } else if (terminal.options.c_abi) {
+        // For C ABI builds, use a custom log function that dispatches to an
+        // embedder-provided callback (or silently discards when none is set).
+        options.logFn = @import("terminal/c/sys.zig").logFn;
+    }
+
+    if (builtin.target.os.tag.isDarwin() and builtin.target.os.tag != .macos) {
+        // If are building for a non-MacOS Darwin target (e.g., iOS), we need to
+        // disable stack tracing for the time being. This is due to the fact that
+        // Zig switched to using _dyld_get_image_header_containing_address and some
+        // other (deprecated) calls to speed up stack unwinding; these calls are
+        // available on MacOS, but not on other platforms.
+        //
+        // A fix has already been submitted to exempt non-MacOS (but still Darwin)
+        // targets, so this can likely be removed in Zig 0.17.0, or a 0.16.x patch
+        // version if it releases beforehand.
+        //
+        // More details:
+        //   https://codeberg.org/ziglang/zig/commit/89f86e46d278a35a613bbc662cdd3f65ffc76ed7
+        //
+        options.allow_stack_tracing = false;
+    }
+
+    break :opts options;
 };
 
+/// True for builds where we keep the full std debug machinery (stack
+/// traces on panic, std.debug.print, etc.). These builds are for
+/// development, where the roughly 160KB of binary size it costs is
+/// worth it.
+const native_freestanding = builtin.target.os.tag == .freestanding and
+    !builtin.target.cpu.arch.isWasm();
+
+const debug_machinery: bool = !native_freestanding and
+    (builtin.is_test or switch (builtin.mode) {
+        .Debug, .ReleaseSafe => true,
+        .ReleaseFast, .ReleaseSmall => false,
+    });
+
+/// The panic handler for when this file is the root module.
+///
+/// In ReleaseFast and ReleaseSmall builds we print the panic message to
+/// stderr and trap, but do not attempt to unwind the stack to print a
+/// stack trace.
+pub const panic: type = if (debug_machinery)
+    std.debug.FullPanic(std.debug.defaultPanic)
+else
+    std.debug.FullPanic(tinyPanicImpl);
+
+/// Guards release builds against accidentally reintroducing the std
+/// debug Io machinery.
+///
+/// `std.Options.debug_io` defaults to `std.Io.Threaded`, and anything
+/// that reaches it (std.debug.print, std.debug.lockStderr, the default
+/// std.log handler, etc.) pins Threaded's entire vtable into the binary:
+/// roughly 110KB of unreachable code.
+///
+/// This verifies nothing ever touches it.
+pub const std_options_debug_io: std.Io = if (debug_machinery)
+    std.Io.Threaded.global_single_threaded.io()
+else
+    @compileError(
+        \\The std debug Io machinery (std.debug.print, std.debug.lockStderr,
+        \\std.log's default handler, ...) is disabled in libghostty-vt release
+        \\builds because it costs ~110KB of binary size. Use std.log (routed
+        \\through our logFn), os/stderr.zig for raw diagnostic writes, or
+        \\gate the code on debug builds.
+    );
+
+/// Prints the panic message to stderr (best-effort) and traps.
+///
+/// This intentionally avoids `std.debug.lockStderr`, which routes through
+/// `std.Options.debug_io` and would keep the entire `std.Io.Threaded`
+/// vtable alive in the binary which takes up hundreds of KB.
+///
+/// This is safe to call from any thread (and even from signal handlers):
+/// it takes no locks, performs no allocation, and touches no shared
+/// mutable state. The message is emitted with a single raw write so that
+/// concurrent stderr output doesn't interleave with it.
+fn tinyPanicImpl(msg: []const u8, ra: ?usize) noreturn {
+    @branchHint(.cold);
+    _ = ra;
+
+    // 256 bytes is enough for most messages, so try that first
+    // so that we can try to write in a single syscall.
+    var buf: [256]u8 = undefined;
+    if (std.fmt.bufPrint(
+        &buf,
+        "panic: {s}\n",
+        .{msg},
+    )) |line| {
+        stderr.write(line);
+    } else |_| {
+        stderr.write("panic: ");
+        stderr.write(msg);
+        stderr.write("\n");
+    }
+
+    // Trap forces a standard crash that embedder-provided debuggers
+    // or environments can catch.
+    @trap();
+}
+
 test {
+    // Zig 0.16.0 has made test logging more strict. Now, *anything* that gets
+    // printed to stderr results in a "failed command" message, even if the
+    // tests ultimately passed. To reduce confusion here (and honestly, test
+    // log spam in general), we bump the default testing log level to error.
+    @import("std").testing.log_level = std.log.Level.err;
+
     _ = terminal;
     _ = @import("lib/main.zig");
     @import("std").testing.refAllDecls(input);