build: add libintl for macOS builds

build.zig.zon

@@ -63,6 +63,7 @@
         .gtk4_layer_shell = .{ .path = "./pkg/gtk4-layer-shell" },
         .harfbuzz = .{ .path = "./pkg/harfbuzz" },
         .highway = .{ .path = "./pkg/highway" },
+        .libintl = .{ .path = "./pkg/libintl" },
         .libpng = .{ .path = "./pkg/libpng" },
         .macos = .{ .path = "./pkg/macos" },
         .oniguruma = .{ .path = "./pkg/oniguruma" },

pkg/libintl/build.zig

@@ -359,6 +359,12 @@ pub fn build(b: *std.Build) !void {
         lib.addIncludePath(b.path(""));
         lib.addIncludePath(upstream.path("gettext-runtime/intl"));
         lib.addIncludePath(upstream.path("gettext-runtime/intl/gnulib-lib"));
+
+        if (target.result.isDarwin()) {
+            const apple_sdk = @import("apple_sdk");
+            try apple_sdk.addPaths(b, &lib.root_module);
+        }
+
         lib.addConfigHeader(config);
         lib.addCSourceFiles(.{
             .root = upstream.path("gettext-runtime/intl"),
@@ -389,12 +395,16 @@ const srcs: []const []const u8 = &.{
     "localealias.c",
     "log.c",
     "ngettext.c",
-    "osdep.c",
     "plural-exp.c",
     "plural.c",
-    "printf.c",
     "setlocale.c",
     "textdomain.c",
     "version.c",
     "compat.c",
+
+    // Not needed for macOS, but we might need them for other platforms.
+    // If we expand this to support other platforms, we should uncomment
+    // these.
+    // "osdep.c",
+    // "printf.c",
 };

pkg/libintl/build.zig.zon

@@ -7,5 +7,7 @@
             .url = "https://deps.files.ghostty.org/gettext-0.24.tar.gz",
             .hash = "1220f870c853529233ea64a108acaaa81f8d06d7ff4b66c76930be7d78d508aff7a2",
         },
+
+        .apple_sdk = .{ .path = "../apple-sdk" },
     },
 }

src/build/SharedDeps.zig

@@ -381,6 +381,17 @@ pub fn add(
         if (self.config.renderer == .opengl) {
             step.linkFramework("OpenGL");
         }
+
+        // Apple platforms do not include libc libintl so we bundle it.
+        // This is LGPL but since our source code is open source we are
+        // in compliance with the LGPL since end users can modify this
+        // build script to replace the bundled libintl with their own.
+        const libintl_dep = b.dependency("libintl", .{
+            .target = target,
+            .optimize = optimize,
+        });
+        step.linkLibrary(libintl_dep.artifact("intl"));
+        try static_libs.append(libintl_dep.artifact("intl").getEmittedBin());
     }
 
     // cimgui