1 files changed, 40 insertions, 0 deletions
diff --git a/src/libc/thread.S b/src/libc/thread.S
new file mode 100644
index 0000000..2900544
--- /dev/null
+++ b/src/libc/thread.S
@@ -0,0 +1,40 @@
+#define ASM_FILE 1
+#include <camellia/syscalls.h>
+#include <camellia/flags.h>
+
+.section .text
+.global thread_creates
+.type thread_creates, @function
+// void thread_creates(int flags, void (*fn)(void*), void *arg, void *stack);
+thread_creates:
+	push %r12
+	push %r13
+	push %r14
+
+	/* save fn, arg, stack */
+	mov %rsi, %r12
+	mov %rdx, %r13
+	mov %rcx, %r14
+
+	mov %rdi, %rsi
+	or $(FORK_SHAREMEM | FORK_SHAREHANDLE), %rsi
+	mov $_SYS_FORK, %rdi
+	xor %rdx, %rdx
+	syscall
+
+	test %rax, %rax
+	jz 1f
+	/* in parent, return normally */
+	pop %r14
+	pop %r13
+	pop %r12
+	ret
+1:	/* in child */
+	mov %r14, %rsp
+	mov %r13, %rdi
+	call *%r12
+
+	mov $_SYS_EXIT, %rdi
+	xor %rsi, %rsi
+	syscall
+	hlt /* if all else fails... */