openbsd

src/libthread/OpenBSD-386-asm.s

@@ -0,0 +1,54 @@
+.globl _tas
+_tas:
+	movl $0xCAFEBABE, %eax
+	movl 4(%esp), %ecx
+	xchgl %eax, 0(%ecx)
+	ret
+
+.globl setmcontext
+setmcontext:
+	movl 4(%esp), %edx
+	movl	8(%edx), %fs
+	movl	12(%edx), %es
+	movl	16(%edx), %ds
+	movl	76(%edx), %ss
+	movl	20(%edx), %edi
+	movl	24(%edx), %esi
+	movl	28(%edx), %ebp
+	movl	%esp, %ecx		 
+	movl	72(%edx), %esp		 
+	pushl	60(%edx)	/* eip */	 
+	pushl	44(%edx)	/* ecx */	 
+	pushl	48(%edx)	/* eax */	 
+	movl	36(%edx), %ebx		 
+	movl	40(%edx), %edx
+	movl	12(%ecx), %eax		 
+	popl	%eax			 
+	popl	%ecx
+	ret
+
+.globl getmcontext
+getmcontext:
+	pushl	%edx
+	movl	8(%esp), %edx
+	movl	%fs, 8(%edx)
+	movl	%es, 12(%edx)
+	movl	%ds, 16(%edx)
+	movl	%ss, 76(%edx)
+	movl	%edi, 20(%edx)
+	movl	%esi, 24(%edx)
+	movl	%ebp, 28(%edx)
+	movl	%ebx, 36(%edx)
+	movl	$1, 48(%edx)
+	popl	%eax
+	movl	%eax, 40(%edx)		 
+	movl	%ecx, 44(%edx)
+	movl	(%esp), %eax	/* eip */		 
+	movl	%eax, 60(%edx)		 
+	movl	%esp, %eax		 
+	addl	$4, %eax	/* setmcontext will re-push the eip */	 
+	movl	%eax, 72(%edx)
+	movl	40(%edx), %edx		 
+	xorl	%eax, %eax		 
+	ret
+

src/libthread/OpenBSD-386.c

@@ -0,0 +1,38 @@
+#include "threadimpl.h"
+
+void
+makecontext(ucontext_t *ucp, void (*func)(void), int argc, ...)
+{
+	int *sp;
+
+	sp = (int*)ucp->uc_stack.ss_sp+ucp->uc_stack.ss_size/4;
+	sp -= argc;
+	memmove(sp, &argc+1, argc*sizeof(int));
+	*--sp = 0;		/* return address */
+	ucp->uc_mcontext.mc_eip = (long)func;
+	ucp->uc_mcontext.mc_esp = (int)sp;
+}
+
+extern int getmcontext(mcontext_t*);
+extern int setmcontext(mcontext_t*);
+
+int
+getcontext(ucontext_t *uc)
+{
+	return getmcontext(&uc->uc_mcontext);
+}
+
+void
+setcontext(ucontext_t *uc)
+{
+	setmcontext(&uc->uc_mcontext);
+}
+
+int
+swapcontext(ucontext_t *oucp, ucontext_t *ucp)
+{
+	if(getcontext(oucp) == 0)
+		setcontext(ucp);
+	return 0;
+}
+