Add ghostty_paste_encode() which encodes paste data for writing to
the terminal pty. It strips unsafe control bytes, wraps in bracketed
paste sequences when requested, and replaces newlines with carriage
returns for unbracketed mode. The input buffer is modified in place
and the encoded result is written to a caller-provided output buffer,
following the same buffer/out_written pattern as the other encode
functions like ghostty_size_report_encode.
Update the c-vt-paste example with an encode_example() demonstrating
the new function and add corresponding @snippet references in the
header documentation.
Add set/get support for foreground, background, cursor, and palette
default colors through ghostty_terminal_set and ghostty_terminal_get.
Four new set options (COLOR_FOREGROUND, COLOR_BACKGROUND, COLOR_CURSOR,
COLOR_PALETTE) write directly to the terminal color defaults. Passing
NULL clears the value for RGB colors or resets the palette to the
built-in default. All set operations mark the palette dirty flag for the
renderer.
Eight new get data types retrieve either the effective color (override
or default, via DynamicRGB.get) or the default color only (ignoring any
OSC overrides). Effective getters for RGB colors return the new NO_VALUE
result code when no color is configured. The palette getters return the
current or original palette respectively.
Adds the GHOSTTY_NO_VALUE result code for cases where a queried value is
simply not configured, distinct from GHOSTTY_INVALID_VALUE which
indicates a caller error.
## Example
```c
#include <ghostty/vt.h>
#include <stdio.h>
int main() {
GhosttyTerminal terminal = NULL;
GhosttyTerminalOptions opts = { .cols = 80, .rows = 24, .max_scrollback = 0 };
ghostty_terminal_new(NULL, &terminal, opts);
// Set default colors
GhosttyColorRgb fg = { .r = 0xDD, .g = 0xDD, .b = 0xDD };
GhosttyColorRgb bg = { .r = 0x1E, .g = 0x1E, .b = 0x2E };
ghostty_terminal_set(terminal, GHOSTTY_TERMINAL_OPT_COLOR_FOREGROUND, &fg);
ghostty_terminal_set(terminal, GHOSTTY_TERMINAL_OPT_COLOR_BACKGROUND, &bg);
// Read back the effective foreground
GhosttyColorRgb color;
if (ghostty_terminal_get(terminal, GHOSTTY_TERMINAL_DATA_COLOR_FOREGROUND, &color)
== GHOSTTY_SUCCESS) {
printf("fg: #%02X%02X%02X\n", color.r, color.g, color.b); // #DDDDDD
}
// After an OSC 10 override from a program inside the terminal:
ghostty_terminal_vt_write(terminal, (const uint8_t*)"\x1B]10;rgb:FF/00/00\x1B\\", 20);
// Effective returns the override, default returns the original
ghostty_terminal_get(terminal, GHOSTTY_TERMINAL_DATA_COLOR_FOREGROUND, &color);
printf("effective: #%02X%02X%02X\n", color.r, color.g, color.b); // #FF0000
ghostty_terminal_get(terminal, GHOSTTY_TERMINAL_DATA_COLOR_FOREGROUND_DEFAULT, &color);
printf("default: #%02X%02X%02X\n", color.r, color.g, color.b); // #DDDDDD
ghostty_terminal_free(terminal);
return 0;
}
```
A full working example is in `example/c-vt-colors/`.
Add set/get support for foreground, background, cursor, and palette
default colors through ghostty_terminal_set and ghostty_terminal_get.
Four new set options (COLOR_FOREGROUND, COLOR_BACKGROUND, COLOR_CURSOR,
COLOR_PALETTE) write directly to the terminal color defaults. Passing
NULL clears the value for RGB colors or resets the palette to the
built-in default. All set operations mark the palette dirty flag for
the renderer.
Eight new get data types retrieve either the effective color (override
or default, via DynamicRGB.get) or the default color only (ignoring
any OSC overrides). Effective getters for RGB colors return the new
NO_VALUE result code when no color is configured. The palette getters
return the current or original palette respectively.
Adds the GHOSTTY_NO_VALUE result code for cases where a queried value
is simply not configured, distinct from GHOSTTY_INVALID_VALUE which
indicates a caller error.
Switch the two Windows CI jobs (build-examples-cmake-windows and
build-libghostty-vt-windows) from GitHub-hosted windows-2025 runners to
namespace-profile-ghostty-windows runners.
Switch the two Windows CI jobs (build-examples-cmake-windows and
build-libghostty-vt-windows) from GitHub-hosted windows-2025 runners
to namespace-profile-ghostty-windows runners.
This makes it so that `zig build dist -Demit-lib-vt` produces a
`libghostty-vt-<version>.tar.gz` source tarball that only contains what
is needed to build and test libghostty-vt (it cannot build Ghostty GUI
on macOS or Linux). `distcheck` has been updated to also verify cmake
works.
The source tarball goes from 38 MB to 2.8 MB for libghostty.
I also updated CI to build and test this, and also contains an assertion
that our tarball is always less than 5 MB so we can be aware if/when we
blow it up.
The `release-tip` job was also updated to add the libghostty-vt tarball
to our tip release on GH.
Run cmake configure and build on the extracted lib-vt tarball as
part of distcheck to ensure the CMake wrapper works from the
stripped archive. Keep dist/cmake/ and dist/libghostty-vt/ in the
archive since the CMake build needs them.
Add a build-dist-lib-vt job that runs distcheck with
-Demit-lib-vt=true and verifies the resulting tarball stays under
5 MB. Also downsize the build-dist runner from -md to -sm.
Add a source-tarball-lib-vt job that builds the stripped lib-vt
dist tarball and publishes it as libghostty-vt-source.tar.gz to
the tip release. Also downsize the source-tarball runner from -md
to -sm since it does not need the extra resources.
When emit_lib_vt is set, the dist tarball is now named
ghostty-vt-<version>.tar.gz and excludes large files that are
unnecessary for building libghostty-vt. This reduces the archive
from ~36MB to ~2.8MB by excluding images, macOS app resources,
font assets, fuzz test corpus, crash testdata, and vendored
libraries not used by lib-vt.
GTK resources and frame data generation are also skipped since
lib-vt does not need them, which removes the GTK build-time
dependency. The distcheck step runs test-lib-vt instead of the
full test suite for lib-vt archives.
**WARNING:** We CANNOT upgrade to Xcode 26.4 with Zig 0.15 because:
https://codeberg.org/ziglang/zig/issues/31658
We have to wait and see if Zig will backport that or if we just have to
roll forward to Zig 0.16 when it comes out. At the time of this commit,
no released Zig version has the fix for that issue.
**WARNING:** We CANNOT upgrade to Xcode 26.4 with Zig 0.15 because:
https://codeberg.org/ziglang/zig/issues/31658
We have to wait and see if Zig will backport that or if we just have to
roll forward to Zig 0.16 when it comes out. At the time of this commit,
no released Zig version has the fix for that issue.
## Summary
- On Windows, install the shared lib as `ghostty.dll` and the static lib
as `ghostty-static.lib` instead of `libghostty.so` and `libghostty.a`
- The `-static` suffix on the static lib avoids collision with the
import lib that the DLL produces (same pattern as
`ghostty-vt-static.lib`)
- Guard `bundle_ubsan_rt` in `GhosttyLib.zig` `initStatic` for Windows,
since Zig's ubsan emits `/exclude-symbols` linker directives that are
incompatible with the MSVC linker (LNK4229). Matches the existing
pattern in `GhosttyLibVt.zig`
Also includes a cherry-pick of PR #11782 (backslash path handling) to
keep the Windows test suite fully passing on this branch.
## Discussion
- Is this better? This is me starting to question Claude's
training/output.
```zig
// Zig's ubsan emits /exclude-symbols linker directives that
// are incompatible with the MSVC linker (LNK4229).
lib.bundle_ubsan_rt = deps.config.target.result.os.tag != .windows;
```
More concise, still preserves the comment. Not sure which is preferred
here. The set-then-override matches `GhosttyLibVt.zig` exactly, but the
boolean is maybe cleaner? Open to either. Curious about your preference.
## Test results
Tested before/after on all three platforms:
| | Windows | Linux | Mac |
|---|---|---|---|
| **BEFORE** (upstream/main) | FAIL (pre-existing, fixed by PR 11782) |
PASS | PASS |
| **AFTER** (this branch) | PASS - 51/51 steps, 2604/2657 tests, 53
skipped | PASS | PASS |
No regressions on any platform.
## What I Learnt
- Zig's build system automatically generates an import `.lib` alongside
a `.dll` on Windows, so the static lib needs a distinct name to avoid
collision.
- The ubsan runtime emits MSVC-incompatible linker directives
On Windows, install as ghostty.dll + ghostty-static.lib instead of
libghostty.so + libghostty.a, following Windows naming conventions.
Guard ubsan_rt bundling in initStatic for MSVC compatibility.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
# What
CommaSplitter treats backslash as an escape character, which breaks
Windows paths like
C:\Users\foo since \U is not a valid escape. On Windows, treat backslash
as a literal character
outside of quoted strings. Inside quotes, escape sequences still work as
before.
Also fix Theme.parseCLI to not mistake the colon in a Windows drive
letter (C:\...) for a
light/dark theme pair separator.
# How
The platform behavior is controlled by a single comptime constant at the
top of CommaSplitter:
const escape_outside_quotes = builtin.os.tag != .windows;
The next() function checks this constant to decide whether backslash
triggers escape parsing
outside quoted strings. All behavior lives in one place.
For Theme, skip colon detection at index 1 on Windows so drive letters
are not mistaken for pair
separators.
Escape-specific tests are skipped on Windows with SkipZigTest.
Windows-specific tests are added
separately to cover paths, literal backslash, and
escapes-still-work-inside-quotes.
# Note
There are other places in config parsing that use colon as a delimiter
without accounting for
Windows drive letters (command.zig prefix parsing, keybind parsing).
Those are separate from this
PR.
# Verified
- zig build test-lib-vt passes on Windows (exit 0)
- No impact on Linux/macOS (the constant is true there, all existing
behavior unchanged)
# What I Learnt
- Platform behavior should live in a single constant or struct, not
scattered across if-else
branches in every test. The escape_outside_quotes constant mirrors the
pattern upstream uses with
PageAlloc = switch(builtin.os.tag) but for a simpler boolean case.
- Use error.SkipZigTest for tests that cannot run on a platform, never
silent returns. This way
the test runner reports them as skipped, not silently passed.
- When fixing a pattern (colon as delimiter), grep the whole codebase
for similar issues even if
you are not fixing them all in one PR. Note them for future work.
This parameterizes all our calling conventions on our C API based on
whether we're building the C lib or Zig lib. If we're building the C
lib, it's C calling convention, else Zig. This lets the Zig module call
the C API via `terminal.c_api.<func>`.
Zig is perfectly capable of calling C ABI but we actually modify our
struct layouts depending on calling conv so you can't actually use the
API prior to this. This fixes that all up.
**Why would you want to do this?** The C API has some different
semantics and stricter care about things like ABI compatibility (in how
it changes structs and so on). It actually might be a more API-stable
API to rely on even from Zig.
When PS1 ends with a bare '%' (e.g. `%3~ %`), concatenating our 133;B
mark (`%{...%}`) directly after it causes zsh's prompt expansion to
interpret the '%' + '{' result as a '%{' escape sequence. This swallows
the 133;B mark and produces a visible '{' in the prompt.
Work around this by doubling a trailing '%' into '%%' before appending
marks, so it expands to a literal '%' and won't merge with the `%{`
token.
When PS1 ends with a bare '%' (e.g. `%3~ %`), concatenating our 133;B
mark (`%{...%}`) directly after it causes zsh's prompt expansion to
interpret the '%' + '{' result as a '%{' escape sequence. This swallows
the 133;B mark and produces a visible '{' in the prompt.
Work around this by doubling a trailing '%' into '%%' before appending
marks, so it expands to a literal '%' and won't merge with the `%{`
token.
Each C API file independently imported ../../lib/allocator.zig as
lib_alloc. Now that terminal/lib.zig re-exports the allocator module
as lib.alloc, use that instead. This removes the redundant import
and keeps all lib dependencies flowing through the single lib.zig
entry point.
Previously every file in the terminal package independently imported
build_options and ../lib/main.zig, then computed the same
lib_target constant. This was repetitive and meant each file needed
both imports just to get the target.
Introduce src/terminal/lib.zig which computes the target once and
re-exports the commonly used lib types (Enum, TaggedUnion, Struct,
String, checkGhosttyHEnum, structSizedFieldFits). All terminal
package files now import lib.zig and use lib.target instead of the
local lib_target constant, removing the per-file boilerplate.
The resize function now requires cell_width_px and cell_height_px
parameters and handles the full resize sequence: computing and setting
width_px/height_px on the terminal, clearing synchronized output mode so
changes display immediately, and encoding a mode 2048 in-band size
report via the write_pty callback when that mode is enabled.
A valid width/height px is critical for some applications and protocols
and some applications rely directly on in-band size reports, so this
change is necessary to support those use cases.
I do wonder if for the Zig API we should be doing this in
`terminal.resize` or somewhere else, because as it stands this has to
all be manually done on the Zig side.
The resize function now requires cell_width_px and cell_height_px
parameters and handles the full resize sequence: computing and
setting width_px/height_px on the terminal, clearing synchronized output mode
so changes display immediately, and encoding a mode 2048 in-band size report
via the write_pty callback when that mode is enabled.
A valid width/height px is critical for some applications and protocols
and some applications rely directly on in-band size reports, so this
change is necessary to support those use cases.
Add total_rows and scrollback_rows as new TerminalData variants
queryable through the existing ghostty_terminal_get interface, using the
cached O(1) total_rows field from PageList rather than introducing
standalone functions.
Add total_rows and scrollback_rows as new TerminalData variants
queryable through the existing ghostty_terminal_get interface,
using the cached O(1) total_rows field from PageList rather than
introducing standalone functions.
Previously ghostty_terminal_set required all values to be passed as
pointers to the value, even when the value itself was already a pointer
(userdata, function pointer callbacks). This forced callers into awkward
patterns like compound literals or intermediate variables just to take
the address of a pointer.
Now pointer-typed options (userdata and all callbacks) are passed
directly as the value parameter. Only non-pointer types like
GhosttyString still require a pointer to the value. This simplifies
InType to return the actual stored type for each option and lets
setTyped work with those types directly.
Previously ghostty_terminal_set required all values to be passed as
pointers to the value, even when the value itself was already a
pointer (userdata, function pointer callbacks). This forced callers
into awkward patterns like compound literals or intermediate
variables just to take the address of a pointer.
Now pointer-typed options (userdata and all callbacks) are passed
directly as the value parameter. Only non-pointer types like
GhosttyString still require a pointer to the value. This
simplifies InType to return the actual stored type for each option
and lets setTyped work with those types directly.
Add title and pwd as both gettable data keys
(GHOSTTY_TERMINAL_DATA_TITLE/PWD) and settable options
(GHOSTTY_TERMINAL_OPT_TITLE/PWD) in the C terminal API. Getting returns
a borrowed GhosttyString; setting copies the data into the terminal via
setTitle/setPwd.
The underlying Terminal.setTitle/setPwd now append a null sentinel so
that getTitle/getPwd can return sentinel-terminated slices ([:0]const
u8), which is useful for downstream consumers that need C strings.
Change ghostty_terminal_set to return GhosttyResult instead of void so
that the new title/pwd options can report allocation failures. Existing
option-setting calls cannot fail so the return value is
backwards-compatible for callers that discard it.
Add title and pwd as both gettable data keys
(GHOSTTY_TERMINAL_DATA_TITLE/PWD) and settable options
(GHOSTTY_TERMINAL_OPT_TITLE/PWD) in the C terminal API. Getting
returns a borrowed GhosttyString; setting copies the data into the
terminal via setTitle/setPwd.
The underlying Terminal.setTitle/setPwd now append a null sentinel so
that getTitle/getPwd can return sentinel-terminated slices ([:0]const
u8), which is useful for downstream consumers that need C strings.
Change ghostty_terminal_set to return GhosttyResult instead of void
so that the new title/pwd options can report allocation failures.
Existing option-setting calls cannot fail so the return value is
backwards-compatible for callers that discard it.
### This is it! This one (and the other stacked PRs) and #11782 should
finally give a clean test run on Windows!
## Summary
- Increase `@setEvalBranchQuota` from 1M to 10M (too much? how much is
too much?) in `checkGhosttyHEnum` (src/lib/enum.zig)
- Fixes the only remaining test failure on Windows MSVC: `ghostty.h
MouseShape`
## Context
This one was fun! Claude started blabbering, diminishing returns it
said. It couldn't figure out. So I called Dario and it worked.
Nah, much easier than that.
On MSVC, the translate-c output for `ghostty.h` is ~360KB with ~2173
declarations (vs ~112KB / ~1502 on Linux/Mac) because `<sys/types.h>`
and `<BaseTsd.h>` pull in Windows SDK headers. The `checkGhosttyHEnum`
function uses a nested `inline for` (enum fields x declarations) with
comptime string comparisons. For MouseShape (34 variants), this
generates roughly 34 x 2173 x ~20 = ~1.5M comptime branches, exceeding
the 1M quota.
The failure was confusing because it presented as a runtime error
("ghostty.h is missing value for GHOSTTY_MOUSE_SHAPE_DEFAULT") rather
than a compile error. The constants exist in the translate-c output and
the test compiles, but the comptime loop silently stops matching when it
hits the branch limit, so `set.remove` is never called and the set
reports all entries as missing at runtime.
## How we found it
The translate-c output clearly had all 34 GHOSTTY_MOUSE_SHAPE_*
constants, yet the test reported all of them as missing. I asked Claude
to list 5 hypotheses (decl truncation, branch quota, string comparison
bug, declaration ordering, field access failure) and to write 7 targeted
POC tests in enum.zig to isolate each step of `checkGhosttyHEnum`:
1. POC1-2: Module access and declaration count (both passed)
2. POC3: `@hasDecl` for the constant (passed)
3. POC4: Direct field value access (passed)
4. POC5: `inline for` over decls with string comparison - **compile
error: "evaluation exceeded 1000 backwards branches"**
5. POC6: Same but with 10M quota (passed)
6. POC7: Full `checkGhosttyHEnum` clone with 10M quota - **passed,
confirming the fix**
POC5 was the key: the default 1000 branch limit for test code confirmed
the comptime budget mechanism. The existing 1M quota in
`checkGhosttyHEnum` was enough for Linux/Mac (1502 declarations) but not
for MSVC (2173 declarations) with larger enums.
## Stack
Stacked on 016-windows/fix-libcxx-msvc.
## Test plan
### Cross-platform results (`zig build test` / `zig build
-Dapp-runtime=none test` on Windows)
| | Windows | Linux | Mac |
|---|---|---|---|
| **BEFORE** (016, ce9930051) | FAIL - 49/51, 2630/2654, 1 test failed,
23 skipped | PASS - 86/86, 2655/2678, 23 skipped | PASS - 160/160,
2655/2662, 7 skipped |
| **AFTER** (017, 68378a0bb) | FAIL - 49/51, 2631/2654, 23 skipped |
PASS - 86/86, 2655/2678, 23 skipped | PASS - 160/160, 2655/2662, 7
skipped |
### Windows: what changed (2630 -> 2631 tests, MouseShape fixed)
**Fixed by this PR:**
- `ghostty.h MouseShape` test - was failing because comptime branch
quota exhaustion silently prevented the inline for loop from matching
any constants
**Remaining failure (pre-existing, unrelated):**
- `config.Config.test.clone can then change conditional state` -
segfaults (exit code 3) on Windows. We investigated this and it looked
familiar.. cherry-picking the `CommaSplitter `fix from PR #11782
resolved it! The backslash path handling in `CommaSplitter `breaks theme
path parsing on Windows, which is exactly what that PR addresses. So
once that lands, we should be in a good place... ready to ship to
Windows users! (just kidding)
### Linux/macOS: no regressions
Identical pass counts and test results before and after.
## What I Learnt
- Comptime branch quota exhaustion in Zig does not always surface as a
clean compile error. When it happens inside an `inline for` loop with
`comptime` string comparisons that gate runtime code (like
`set.remove`), the effect is that matching code is silently not
generated. The test compiles and runs, but the runtime behavior is wrong
because the matching branches were never emitted. This makes the failure
look like a data issue (missing declarations) rather than a compile
budget issue.
- When debugging comptime issues, writing small isolated POC tests that
exercise each step of the failing function independently is very
effective. It took 7 targeted tests to pinpoint the exact failure point.
- Cross-platform translate-c outputs can vary significantly in size. On
MSVC, system headers are much larger than on Linux/Mac, which affects
comptime budgets for any code that iterates over translated module
declarations.
Replace the O(N×M) nested inline for loop with direct @hasDecl lookups.
The old approach iterated over all translate-c declarations for each enum
field, which required a 10M comptime branch quota on MSVC (2173 decls ×
138 fields × ~20 branches). The new approach constructs the expected
declaration name and checks directly, reducing to O(N) and needing only
100K quota on all platforms.
Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
The DA1 trampoline was converting C feature codes into a local
stack buffer and returning a slice pointing into it. This is
unsound because the slice outlives the stack frame once the
trampoline returns, leaving reportDeviceAttributes reading
invalid memory.
Move the scratch buffer into the wrapper effects struct so that
its lifetime extends beyond the trampoline call, keeping the
returned slice valid for the caller.
Add a comprehensive "Effects" section to the terminal module
documentation in terminal.h explaining the callback system that
lets embedding applications react to terminal-initiated events
(bell, title changes, pty writes, device queries, etc.). The
section includes a reference table of all available effects and
their triggers, plus @snippet references to the new example.
Add c-vt-effects example project demonstrating how to register
write_pty, bell, and title_changed callbacks, attach userdata,
and feed VT data that triggers each effect.
Assign handler.effects as a struct literal instead of setting fields
individually. This lets the compiler catch missing fields if new
effects are added to the Effects struct.
Also sort the callback function typedefs in vt/terminal.h
alphabetically (Bell, ColorScheme, DeviceAttributes, Enquiry, Size,
TitleChanged, WritePty, Xtversion).
Rename device_status.h to device.h and add C-compatible structs for
device attributes (DA1/DA2/DA3) responses. The new header includes
defines for all known conformance levels, DA1 feature codes, and DA2
device type identifiers.
Add a GhosttyTerminalDeviceAttributesFn callback that C consumers can
set via GHOSTTY_TERMINAL_OPT_DEVICE_ATTRIBUTES. The callback follows
the existing bool + out-pointer pattern used by color_scheme and size
callbacks. When the callback is unset or returns false, the trampoline
returns a default VT220 response (conformance level 62, ANSI color).
The DA1 primary features use a fixed [64]uint16_t inline array with a
num_features count rather than a pointer, so the entire struct is
value-typed and can be safely copied without lifetime concerns.
Change device_status.ColorScheme from a plain Zig enum to
lib.Enum so it uses c_int backing when targeting the C ABI.
Add a color_scheme callback to the C terminal effects, following
the bool + out-pointer pattern used by the size callback. The
trampoline converts between the C calling convention and the
internal stream handler color_scheme effect, returning null when
no callback is set.
Add device_status.h header with GhosttyColorScheme enum and wire
it through terminal.h as GHOSTTY_TERMINAL_OPT_COLOR_SCHEME (= 7)
with GhosttyTerminalColorSchemeFn.
Add GHOSTTY_TERMINAL_OPT_SIZE so C consumers can respond to
XTWINOPS size queries (CSI 14/16/18 t). The callback receives a
GhosttySizeReportSize out-pointer and returns true if the size is
available, or false to silently ignore the query. The trampoline
converts the bool + out-pointer pattern to the optional that the
Zig handler expects.
Add GHOSTTY_TERMINAL_OPT_TITLE_CHANGED so C consumers are notified
when the terminal title changes via OSC 0 or OSC 2 sequences. The
callback has the same fire-and-forget shape as bell.
Add GHOSTTY_TERMINAL_OPT_ENQUIRY and GHOSTTY_TERMINAL_OPT_XTVERSION
so C consumers can respond to ENQ (0x05) and XTVERSION (CSI > q)
queries. Both callbacks return a GhosttyString rather than using
out-pointers.
Introduce GhosttyString in types.h as a borrowed byte string
(ptr + len) backed by lib.String on the Zig side. This will be
reusable for future callbacks that need to return string data.
Without an xtversion callback the trampoline returns an empty
string, which causes the handler to report the default
"libghostty" version. Without an enquiry callback no response
is sent.
Test that the write_pty callback receives correct DECRQM response
data and userdata, that queries are silently ignored without a
callback, and that setting null clears the callback. Test that
the bell callback fires on single and multiple BEL characters
with correct userdata, and that BEL without a callback is safe.
Add GHOSTTY_TERMINAL_OPT_BELL so C consumers can receive bell
notifications during VT processing. The bell trampoline follows
the same pattern as write_pty.
Move the C function pointer typedefs (WritePtyFn, BellFn) into
the Effects struct namespace to keep callback types co-located
with their storage and trampolines.
Add a typed option setter ghostty_terminal_set() following the
existing setopt pattern used by the key encoder and render state
APIs. This is the first step toward exposing stream_terminal
Handler.Effects through the C API.
The initial implementation includes a write_pty callback and a
shared userdata pointer. The write_pty callback is invoked
synchronously during ghostty_terminal_vt_write() when the terminal
needs to send a response back to the pty, such as DECRQM mode
reports or device status responses.
Trampolines are always installed at terminal creation time and
no-op when no C callback is set, so callers can configure
callbacks at any point without reinitializing the stream. The C
callback state is grouped into an internal Effects struct on the
TerminalWrapper to simplify adding more callbacks in the future.
> [!WARNING]
> Review/approve this AFTER #11807 and #11810 (this PR includes their
commits)
## Summary
### **And `run test ghostty-test` finally runs on Windows! 🎉almost
there!**
- Skip `linkLibCpp()` on MSVC for dcimgui, spirv-cross, and harfbuzz
(same fix already applied upstream to highway, simdutf, utfcpp, glslang,
SharedDeps, GhosttyZig)
- Fix freetype C enum signedness: MSVC translates C enums as signed
`int`, while GCC/Clang uses unsigned `int`. Add `@intCast` at call sites
and `@bitCast` for bit-shift operations on glyph format tags.
## Context
Zig unconditionally passes `-nostdinc++` and adds its bundled
libc++/libc++abi include paths, which conflict with MSVC's own C++
runtime headers. The MSVC SDK directories (added via `linkLibC`) already
contain both C and C++ headers, so `linkLibCpp` is not needed.
The freetype enum issue is a different facet of the same MSVC vs
GCC/Clang divide: `FT_Render_Mode` and `FT_Glyph_Format` are C enums
that get different signedness on different compilers.
## Stack
Stacked on 015-windows/fix-ssize-t-msvc.
## Test plan
### Cross-platform results (`zig build test` / `zig build
-Dapp-runtime=none test` on Windows)
| | Windows | Linux | Mac |
|---|---|---|---|
| **BEFORE** (015, a35f84db3) | FAIL - 48/51, 1 failed (compile
ghostty-test) | PASS - 86/86, 2655/2678, 23 skipped | PASS - 160/160,
2655/2662, 7 skipped |
| **AFTER** (016, ce9930051) | FAIL - 49/51, 2630/2654 tests passed, 1
failed, 23 skipped | PASS - 86/86, 2655/2678, 23 skipped | PASS -
160/160, 2655/2662, 7 skipped |
### Windows: what changed (48 -> 49 steps, tests now run)
**Fixed by this PR:**
- `compile test ghostty-test` - was `3 errors` (libcxxabi conflicts +
freetype type mismatches) -> `success`
- `run test ghostty-test` - now actually runs: 2630 passed, 23 skipped,
1 failed
**Remaining test failure (pre-existing, unrelated):**
- `ghostty.h MouseShape` - `checkGhosttyHEnum` cannot find
`GHOSTTY_MOUSE_SHAPE_*` constants in the translate-c output. This is a
translate-c issue with how MSVC enum constants are exposed, not related
to C++ linking or enum signedness.
### Linux/macOS: no regressions
Identical pass counts and test results before and after.
## Discussion
### Grep wider: other unconditional linkLibCpp calls
`pkg/breakpad/build.zig` still calls `linkLibCpp()` unconditionally but
is behind sentry and not in the Windows build path. Noted for
completeness.
### Freetype enum signedness
The freetype Zig bindings define `RenderMode = enum(c_uint)` and
`Encoding = enum(u31)`. On MSVC, C enums are `int` (signed), so the
translated C functions expect `c_int` parameters. The fix adds
`@intCast` to convert between signed and unsigned at call sites. This is
safe because the enum values are small positive integers that fit in
both types.
Also, not sure if there's a better way to make this change more
elegantly. The comments are replicated in each instance, probably
overkill but I have seen this same pattern elsewhere in the codebase.
## What I Learnt
- More of the same
