Emscripten uses its own glfw library (#8)

README.md

@@ -11,7 +11,10 @@ pub fn build(b: *std.Build) void {
 
     const zglfw = b.dependency("zglfw", .{});
     exe.root_module.addImport("zglfw", zglfw.module("root"));
-    exe.linkLibrary(zglfw.artifact("glfw"));
+
+    if (target.result.os.tag != .emscrpten) {
+        exe.linkLibrary(zglfw.artifact("glfw"));
+    }
 }
 ```
 

build.zig

@@ -36,6 +36,8 @@ pub fn build(b: *std.Build) void {
         },
     });
 
+    if (target.result.os.tag == .emscripten) return;
+
     const glfw = if (options.shared) blk: {
         const lib = b.addSharedLibrary(.{
             .name = "glfw",

src/zglfw.zig

@@ -1107,3 +1107,26 @@ fn _isLinuxDesktopLike() bool {
         else => false,
     };
 }
+
+//--------------------------------------------------------------------------------------------------
+//
+// Emscripten
+//
+//--------------------------------------------------------------------------------------------------
+const os = builtin.target.os.tag;
+usingnamespace if (os == .emscripten or os == .freestanding) struct {
+    // GLFW - emscripten uses older version that doesn't have these functions - implement dummies
+    var glfwGetGamepadStateWarnPrinted: bool = false;
+    pub export fn glfwGetGamepadState(_: i32, _: ?*anyopaque) i32 {
+        if (!glfwGetGamepadStateWarnPrinted) {
+            std.log.err("glfwGetGamepadState(): not implemented! Use emscripten specific functions: https://emscripten.org/docs/api_reference/html5.h.html?highlight=gamepadstate#c.emscripten_get_gamepad_status", .{});
+            glfwGetGamepadStateWarnPrinted = true;
+        }
+        return 0; // false - failure
+    }
+
+    /// use glfwSetCallback instead
+    pub export fn glfwGetError() i32 {
+        return 0; // no error
+    }
+} else struct {};