From d33beedcd05e887a62349ae484ef508c4ca8a45d Mon Sep 17 00:00:00 2001
From: Folkert <folkert@folkertdev.nl>
Date: Wed, 13 Jul 2022 14:40:07 +0200
Subject: [PATCH] add the zig bits for expects

---
 .../compiler/builtins/bitcode/src/expect.zig  | 39 +++++++++++++++++++
 crates/compiler/builtins/bitcode/src/main.zig |  6 +++
 crates/compiler/builtins/src/bitcode.rs       |  3 ++
 3 files changed, 48 insertions(+)
 create mode 100644 crates/compiler/builtins/bitcode/src/expect.zig

diff --git a/crates/compiler/builtins/bitcode/src/expect.zig b/crates/compiler/builtins/bitcode/src/expect.zig
new file mode 100644
index 0000000000..16cc4db86f
--- /dev/null
+++ b/crates/compiler/builtins/bitcode/src/expect.zig
@@ -0,0 +1,39 @@
+const std = @import("std");
+
+extern fn shm_open(name: *const i8, oflag: c_int, mode: c_uint) c_int;
+extern fn mmap(addr: ?*anyopaque, length: c_uint, prot: c_int, flags: c_int, fd: c_int, offset: c_uint) *anyopaque;
+extern fn kill(pid: c_int, sig: c_int) c_int;
+extern fn getppid() c_int;
+
+const SIGUSR1: c_int = 10;
+
+const O_RDWR: c_int = 2;
+const O_CREAT: c_int = 64;
+
+pub const PROT_WRITE: c_int = 2;
+pub const MAP_SHARED: c_int = 0x0001;
+
+pub fn expectFailedStart() callconv(.C) [*]u8 {
+    const name = "/roc_expect_buffer"; // IMPORTANT: shared memory object names must begin with / and contain no other slashes!
+
+    const shared_fd = shm_open(@ptrCast(*const i8, name), O_RDWR | O_CREAT, 0o666);
+
+    const shared_ptr = mmap(
+        null,
+        4096,
+        PROT_WRITE,
+        MAP_SHARED,
+        shared_fd,
+        0,
+    );
+
+    const ptr = @ptrCast([*]u8, shared_ptr);
+
+    return ptr;
+}
+
+pub fn expectFailedFinalize() callconv(.C) void {
+    const parent_pid = getppid();
+
+    _ = kill(parent_pid, SIGUSR1);
+}
diff --git a/crates/compiler/builtins/bitcode/src/main.zig b/crates/compiler/builtins/bitcode/src/main.zig
index 337c87d3e3..2823fe6c45 100644
--- a/crates/compiler/builtins/bitcode/src/main.zig
+++ b/crates/compiler/builtins/bitcode/src/main.zig
@@ -2,6 +2,7 @@ const std = @import("std");
 const builtin = @import("builtin");
 const math = std.math;
 const utils = @import("utils.zig");
+const expect = @import("expect.zig");
 
 const ROC_BUILTINS = "roc_builtins";
 const NUM = "num";
@@ -162,6 +163,11 @@ comptime {
 
     @export(utils.panic, .{ .name = "roc_builtins.utils." ++ "panic", .linkage = .Weak });
 
+    if (builtin.target.cpu.arch != .wasm32) {
+        exportUtilsFn(expect.expectFailedStart, "expect_failed_start");
+        exportUtilsFn(expect.expectFailedFinalize, "expect_failed_finalize");
+    }
+
     if (builtin.target.cpu.arch == .aarch64) {
         @export(__roc_force_setjmp, .{ .name = "__roc_force_setjmp", .linkage = .Weak });
         @export(__roc_force_longjmp, .{ .name = "__roc_force_longjmp", .linkage = .Weak });
diff --git a/crates/compiler/builtins/src/bitcode.rs b/crates/compiler/builtins/src/bitcode.rs
index 345ac4fcdd..55472c4abc 100644
--- a/crates/compiler/builtins/src/bitcode.rs
+++ b/crates/compiler/builtins/src/bitcode.rs
@@ -375,6 +375,9 @@ pub const UTILS_INCREF: &str = "roc_builtins.utils.incref";
 pub const UTILS_DECREF: &str = "roc_builtins.utils.decref";
 pub const UTILS_DECREF_CHECK_NULL: &str = "roc_builtins.utils.decref_check_null";
 
+pub const UTILS_EXPECT_FAILED_START: &str = "roc_builtins.utils.expect_failed_start";
+pub const UTILS_EXPECT_FAILED_FINALIZE: &str = "roc_builtins.utils.expect_failed_finalize";
+
 pub const UTILS_LONGJMP: &str = "longjmp";
 pub const UTILS_SETJMP: &str = "setjmp";