all: basic support for the os package

The resulting binary is pretty big due to lacking optimizations
(probably because of interfaces), so that should be fixed.

src/runtime/atomic.go

@@ -0,0 +1,24 @@
+package runtime
+
+// This file contains implementations for the sync/atomic package.
+
+// All implementations assume there are no goroutines, threads or interrupts.
+
+//go:linkname loadUint64 sync/atomic.LoadUint64
+func loadUint64(addr *uint64) uint64 {
+	return *addr
+}
+
+//go:linkname storeUint32 sync/atomic.StoreUint32
+func storeUint32(addr *uint32, val uint32) {
+	*addr = val
+}
+
+//go:linkname compareAndSwapUint64 sync/atomic.CompareAndSwapUint64
+func compareAndSwapUint64(addr *uint64, old, new uint64) bool {
+	if *addr == old {
+		*addr = new
+		return true
+	}
+	return false
+}

src/runtime/poll.go

@@ -0,0 +1,23 @@
+package runtime
+
+// This file implements stub functions for internal/poll.
+
+//go:linkname poll_runtime_pollServerInit internal/poll.runtime_pollServerInit
+func poll_runtime_pollServerInit(ctx *uint8) {
+	panic("todo: runtime_pollServerInit")
+}
+
+//go:linkname poll_runtime_pollOpen internal/poll.runtime_pollOpen
+func poll_runtime_pollOpen(fd uintptr) (uintptr, int) {
+	panic("todo: runtime_pollOpen")
+}
+
+//go:linkname poll_runtime_pollClose internal/poll.runtime_pollClose
+func poll_runtime_pollClose(ctx uintptr) {
+	panic("todo: runtime_pollClose")
+}
+
+//go:linkname poll_runtime_pollUnblock internal/poll.runtime_pollUnblock
+func poll_runtime_pollUnblock(ctx uintptr) {
+	panic("todo: runtime_pollUnblock")
+}

src/runtime/runtime.go

@@ -49,6 +49,11 @@ func GOROOT() string {
 	return "/usr/local/go"
 }
 
+//go:linkname os_runtime_args os.runtime_args
+func os_runtime_args() []string {
+	return nil
+}
+
 // Copy size bytes from src to dst. The memory areas must not overlap.
 func memcpy(dst, src unsafe.Pointer, size uintptr) {
 	for i := uintptr(0); i < size; i++ {

src/runtime/sync.go

@@ -1 +1,13 @@
 package runtime
+
+// This file contains stub implementations for internal/poll.
+
+//go:linkname semacquire internal/poll.runtime_Semacquire
+func semacquire(sema *uint32) {
+	panic("todo: semacquire")
+}
+
+//go:linkname semrelease internal/poll.runtime_Semrelease
+func semrelease(sema *uint32) {
+	panic("todo: semrelease")
+}

src/runtime/syscall.go

@@ -0,0 +1,13 @@
+package runtime
+
+// This file implements syscall.Syscall and the like.
+
+//go:linkname syscall_Syscall syscall.Syscall
+func syscall_Syscall(trap, a1, a2, a3 uintptr) (r1, r2 uintptr, err uintptr) {
+	panic("syscall")
+}
+
+//go:linkname syscall_Syscall6 syscall.Syscall6
+func syscall_Syscall6(trap, a1, a2, a3, a4, a5, a6 uintptr) (r1, r2 uintptr, err uintptr) {
+	panic("syscall6")
+}