From bd5969fc876a10b18613302db7087ef3c40f18e1 Mon Sep 17 00:00:00 2001
From: Ian Moffett <ian@osmora.org>
Date: Thu, 7 Mar 2024 17:28:00 -0500
Subject: lib: Add mlibc

Signed-off-by: Ian Moffett <ian@osmora.org>
---
 lib/mlibc/sysdeps/keyronex/generic/thread.cpp | 80 +++++++++++++++++++++++++++
 1 file changed, 80 insertions(+)
 create mode 100644 lib/mlibc/sysdeps/keyronex/generic/thread.cpp

(limited to 'lib/mlibc/sysdeps/keyronex/generic/thread.cpp')

diff --git a/lib/mlibc/sysdeps/keyronex/generic/thread.cpp b/lib/mlibc/sysdeps/keyronex/generic/thread.cpp
new file mode 100644
index 0000000..cafb74a
--- /dev/null
+++ b/lib/mlibc/sysdeps/keyronex/generic/thread.cpp
@@ -0,0 +1,80 @@
+#include <sys/mman.h>
+#include <mlibc/debug.hpp>
+#include <errno.h>
+#include <mlibc/all-sysdeps.hpp>
+#include <bits/ensure.h>
+#include <mlibc/tcb.hpp>
+#include <keyronex/syscall.h>
+
+extern "C" void __mlibc_thread_trampoline(void *(*fn)(void *), Tcb *tcb, void *arg) {
+	if (mlibc::sys_tcb_set(tcb)) {
+		__ensure(!"failed to set tcb for new thread");
+	}
+
+	while (__atomic_load_n(&tcb->tid, __ATOMIC_RELAXED) == 0) {
+		mlibc::sys_futex_wait(&tcb->tid, 0, nullptr);
+	}
+
+	tcb->invokeThreadFunc(reinterpret_cast<void *>(fn), arg);
+
+	__atomic_store_n(&tcb->didExit, 1, __ATOMIC_RELEASE);
+	mlibc::sys_futex_wake(&tcb->didExit);
+
+	mlibc::sys_thread_exit();
+}
+
+#define DEFAULT_STACK 0x400000
+
+namespace mlibc {
+
+extern "C" void __mlibc_thread_entry();
+
+	int sys_clone(void *tcb, pid_t *tid_out, void *stack) {
+		(void)tcb;
+
+		auto ret = syscall2(kPXSysForkThread, (uintptr_t)__mlibc_thread_entry, (uintptr_t)stack, NULL);
+		if (int e = sc_error(ret); e)
+			return e;
+
+		*tid_out = ret;
+		return 0;
+	}
+
+	int sys_prepare_stack(void **stack, void *entry, void *arg, void *tcb, size_t *stack_size, size_t *guard_size, void **stack_base) {
+		// TODO guard
+
+		mlibc::infoLogger() << "mlibc: sys_prepare_stack() does not setup a guard!" << frg::endlog;
+
+		*guard_size = 0;
+
+		*stack_size = *stack_size ? *stack_size : DEFAULT_STACK;
+
+		if (!*stack) {
+			*stack_base = mmap(NULL, *stack_size, PROT_READ | PROT_WRITE, MAP_ANONYMOUS | MAP_PRIVATE, -1, 0);
+			if (*stack_base == MAP_FAILED) {
+				return errno;
+			}
+		} else {
+			*stack_base = *stack;
+		}
+		
+		*stack = (void *)((char *)*stack_base + *stack_size);
+
+		void **stack_it = (void **)*stack;
+
+		*--stack_it = arg;
+		*--stack_it = tcb;
+		*--stack_it = entry;
+
+		*stack = (void *)stack_it;
+
+		return 0;
+	}
+
+	void sys_thread_exit() {
+		mlibc::panicLogger() << "mlibc: sys_thread_exit unimplemented!" << frg::endlog;
+		__builtin_unreachable();
+	}
+
+
+}
-- 
cgit v1.2.3