/* Copyright 2015 Yoshinori Sato <ysato@users.sourceforge.jp> */ /* clone is even more special than fork as it mucks with stacks and invokes a function in the right context after its all over. */ #define _ERRNO_H #include <bits/errno.h> #include <sys/syscall.h> /* int _clone(int (*fn)(void *arg), void *child_stack, int flags, void *arg void *parent_tidptr, void *tls, void *child_tidptr) */ #ifdef __H8300H__ .h8300h #endif #ifdef __H8300S__ .h8300s #endif .text .globl clone clone: /* Sanity check arguments. */ mov.l #-EINVAL,er3 mov.l er0,er0 /* no NULL function pointers */ beq __syscall_error mov.l er1,er1 /* no NULL stack pointers */ beq __syscall_error /* Allocate space and copy the argument onto the new stack. */ mov.l @(4:16,sp),er3 mov.l er3,@-er1 /* setup argument */ mov.l er0,er3 /* er3 = child entry */ sub.l #20,sp mov.l er2,@sp /* flags */ mov.l er1,@(4,sp) /* new sp */ mov.l sp,er1 mov.l @(20+8,sp),er0 mov.l er0,@er1 /* parent tid */ adds #4,er1 mov.l @(20+16,sp),er0 mov.l er0,@er1 /* child tid */ adds #4,er1 mov.l @(20+12,sp),er0 mov.l er0,@er1 /* tls */ /* do the system call */ mov.l sp,er1 mov.l #__NR_clone,er0 trapa #0 add.l #20,sp mov.l er0,er0 bmi __syscall_error beq thread_start rts __syscall_error: neg.l er0 mov.l er0,@-sp #if !defined(__PIC__) jsr @__errno_location #else mov.l @(__errno_location@GOTOFF,er5),er1 jsr @er1 #endif mov.l @sp,er1 mov.l er1,@er0 sub.l er0,er0 dec.l #1,er0 rts thread_start: mov.l @sp+,er0 /* restore args */ jsr @er3 mov.l er0,er1 mov.l #__NR_exit,er0 trapa #0 .end