build: ghostty lib, framework, build into app

src/build/XCFrameworkStep.zig

@@ -0,0 +1,78 @@
+//! A zig builder step that runs "swift build" in the context of
+//! a Swift project managed with SwiftPM. This is primarily meant to build
+//! executables currently since that is what we build.
+const XCFrameworkStep = @This();
+
+const std = @import("std");
+const Step = std.build.Step;
+const GeneratedFile = std.build.GeneratedFile;
+
+pub const Options = struct {
+    /// The name of the xcframework to create.
+    name: []const u8,
+
+    /// The path to write the framework
+    out_path: []const u8,
+
+    /// Library file (dylib, a) to package.
+    library: std.build.FileSource,
+
+    /// Path to a directory with the headers.
+    headers: std.build.FileSource,
+};
+
+step: Step,
+builder: *std.build.Builder,
+
+/// See Options
+name: []const u8,
+out_path: []const u8,
+library: std.build.FileSource,
+headers: std.build.FileSource,
+
+pub fn create(builder: *std.build.Builder, opts: Options) *XCFrameworkStep {
+    const self = builder.allocator.create(XCFrameworkStep) catch @panic("OOM");
+    self.* = .{
+        .step = Step.init(.custom, builder.fmt(
+            "xcframework {s}",
+            .{opts.name},
+        ), builder.allocator, make),
+        .builder = builder,
+        .name = opts.name,
+        .out_path = opts.out_path,
+        .library = opts.library,
+        .headers = opts.headers,
+    };
+    return self;
+}
+
+fn make(step: *Step) !void {
+    const self = @fieldParentPtr(XCFrameworkStep, "step", step);
+
+    // TODO: use the zig cache system when it is in the stdlib
+    // https://github.com/ziglang/zig/pull/14571
+    const output_path = self.out_path;
+
+    // We use a RunStep here to ease our configuration.
+    {
+        const run = std.build.RunStep.create(self.builder, self.builder.fmt(
+            "xcframework delete {s}",
+            .{self.name},
+        ));
+        run.addArgs(&.{ "rm", "-rf", output_path });
+        try run.step.make();
+    }
+    {
+        const run = std.build.RunStep.create(self.builder, self.builder.fmt(
+            "xcframework {s}",
+            .{self.name},
+        ));
+        run.addArgs(&.{
+            "xcodebuild", "-create-xcframework",
+            "-library",   self.library.getPath(self.builder),
+            "-headers",   self.headers.getPath(self.builder),
+            "-output",    output_path,
+        });
+        try run.step.make();
+    }
+}

src/main_c.zig

@@ -0,0 +1,11 @@
+// This is the main file for the C API. The C API is used to embed Ghostty
+// within other applications. Depending on the build settings some APIs
+// may not be available (i.e. embedding into macOS exposes various Metal
+// support).
+const std = @import("std");
+const builtin = @import("builtin");
+
+// We're just testing right now.
+export fn ghostty_hello() u64 {
+    return 42;
+}