зеркало из https://github.com/github/ruby.git
1041 строка
26 KiB
C
1041 строка
26 KiB
C
/**********************************************************************
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cont.c -
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$Author$
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created at: Thu May 23 09:03:43 2007
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Copyright (C) 2007 Koichi Sasada
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**********************************************************************/
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#include "ruby/ruby.h"
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#include "vm_core.h"
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#include "gc.h"
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#include "eval_intern.h"
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#define CAPTURE_JUST_VALID_VM_STACK 1
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enum context_type {
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CONTINUATION_CONTEXT = 0,
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FIBER_CONTEXT = 1,
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ROOT_FIBER_CONTEXT = 2
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};
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typedef struct rb_context_struct {
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enum context_type type;
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VALUE self;
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int argc;
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VALUE value;
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VALUE *vm_stack;
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#ifdef CAPTURE_JUST_VALID_VM_STACK
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int vm_stack_slen; /* length of stack (head of th->stack) */
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int vm_stack_clen; /* length of control frames (tail of th->stack) */
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#endif
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VALUE *machine_stack;
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VALUE *machine_stack_src;
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#ifdef __ia64
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VALUE *machine_register_stack;
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VALUE *machine_register_stack_src;
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int machine_register_stack_size;
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#endif
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rb_thread_t saved_thread;
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rb_jmpbuf_t jmpbuf;
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int machine_stack_size;
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} rb_context_t;
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enum fiber_status {
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CREATED,
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RUNNING,
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TERMINATED
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};
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typedef struct rb_fiber_struct {
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rb_context_t cont;
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VALUE prev;
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enum fiber_status status;
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struct rb_fiber_struct *prev_fiber;
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struct rb_fiber_struct *next_fiber;
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} rb_fiber_t;
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static VALUE rb_cContinuation;
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static VALUE rb_cFiber;
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static VALUE rb_eFiberError;
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#define GetContPtr(obj, ptr) \
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Data_Get_Struct(obj, rb_context_t, ptr)
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#define GetFiberPtr(obj, ptr) do {\
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ptr = (rb_fiber_t*)DATA_PTR(obj);\
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if (!ptr) rb_raise(rb_eFiberError, "uninitialized fiber");\
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} while(0)
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NOINLINE(static VALUE cont_capture(volatile int *stat));
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void rb_thread_mark(rb_thread_t *th);
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static void
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cont_mark(void *ptr)
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{
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RUBY_MARK_ENTER("cont");
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if (ptr) {
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rb_context_t *cont = ptr;
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rb_gc_mark(cont->value);
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rb_thread_mark(&cont->saved_thread);
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if (cont->vm_stack) {
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#ifdef CAPTURE_JUST_VALID_VM_STACK
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rb_gc_mark_locations(cont->vm_stack,
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cont->vm_stack + cont->vm_stack_slen + cont->vm_stack_clen);
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#else
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rb_gc_mark_localtion(cont->vm_stack,
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cont->vm_stack, cont->saved_thread.stack_size);
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#endif
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}
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if (cont->machine_stack) {
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rb_gc_mark_locations(cont->machine_stack,
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cont->machine_stack + cont->machine_stack_size);
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}
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#ifdef __ia64
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if (cont->machine_register_stack) {
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rb_gc_mark_locations(cont->machine_register_stack,
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cont->machine_register_stack + cont->machine_register_stack_size);
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}
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#endif
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}
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RUBY_MARK_LEAVE("cont");
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}
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static void
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cont_free(void *ptr)
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{
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RUBY_FREE_ENTER("cont");
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if (ptr) {
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rb_context_t *cont = ptr;
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RUBY_FREE_UNLESS_NULL(cont->saved_thread.stack); fflush(stdout);
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RUBY_FREE_UNLESS_NULL(cont->machine_stack);
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#ifdef __ia64
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RUBY_FREE_UNLESS_NULL(cont->machine_register_stack);
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#endif
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RUBY_FREE_UNLESS_NULL(cont->vm_stack);
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/* free rb_cont_t or rb_fiber_t */
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ruby_xfree(ptr);
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}
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RUBY_FREE_LEAVE("cont");
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}
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static void
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fiber_mark(void *ptr)
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{
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RUBY_MARK_ENTER("cont");
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if (ptr) {
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rb_fiber_t *fib = ptr;
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rb_gc_mark(fib->prev);
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cont_mark(&fib->cont);
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}
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RUBY_MARK_LEAVE("cont");
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}
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static void
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fiber_link_join(rb_fiber_t *fib)
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{
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VALUE current_fibval = rb_fiber_current();
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rb_fiber_t *current_fib;
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GetFiberPtr(current_fibval, current_fib);
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/* join fiber link */
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fib->next_fiber = current_fib->next_fiber;
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fib->prev_fiber = current_fib;
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current_fib->next_fiber->prev_fiber = fib;
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current_fib->next_fiber = fib;
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}
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static void
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fiber_link_remove(rb_fiber_t *fib)
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{
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fib->prev_fiber->next_fiber = fib->next_fiber;
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fib->next_fiber->prev_fiber = fib->prev_fiber;
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}
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static void
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fiber_free(void *ptr)
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{
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RUBY_FREE_ENTER("fiber");
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if (ptr) {
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rb_fiber_t *fib = ptr;
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if (fib->cont.type != ROOT_FIBER_CONTEXT) {
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st_free_table(fib->cont.saved_thread.local_storage);
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}
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fiber_link_remove(fib);
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cont_free(&fib->cont);
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}
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RUBY_FREE_LEAVE("fiber");
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}
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static void
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cont_save_machine_stack(rb_thread_t *th, rb_context_t *cont)
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{
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int size;
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rb_thread_t *sth = &cont->saved_thread;
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SET_MACHINE_STACK_END(&th->machine_stack_end);
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#ifdef __ia64
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th->machine_register_stack_end = rb_ia64_bsp();
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#endif
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if (th->machine_stack_start > th->machine_stack_end) {
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size = cont->machine_stack_size = th->machine_stack_start - th->machine_stack_end;
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cont->machine_stack_src = th->machine_stack_end;
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}
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else {
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size = cont->machine_stack_size = th->machine_stack_end - th->machine_stack_start;
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cont->machine_stack_src = th->machine_stack_start;
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}
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if (cont->machine_stack) {
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REALLOC_N(cont->machine_stack, VALUE, size);
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}
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else {
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cont->machine_stack = ALLOC_N(VALUE, size);
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}
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FLUSH_REGISTER_WINDOWS;
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MEMCPY(cont->machine_stack, cont->machine_stack_src, VALUE, size);
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#ifdef __ia64
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rb_ia64_flushrs();
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size = cont->machine_register_stack_size = th->machine_register_stack_end - th->machine_register_stack_start;
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cont->machine_register_stack_src = th->machine_register_stack_start;
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if (cont->machine_register_stack) {
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REALLOC_N(cont->machine_register_stack, VALUE, size);
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}
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else {
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cont->machine_register_stack = ALLOC_N(VALUE, size);
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}
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MEMCPY(cont->machine_register_stack, cont->machine_register_stack_src, VALUE, size);
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#endif
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sth->machine_stack_start = sth->machine_stack_end = 0;
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#ifdef __ia64
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sth->machine_register_stack_start = sth->machine_register_stack_end = 0;
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#endif
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}
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static void
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cont_init(rb_context_t *cont)
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{
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rb_thread_t *th = GET_THREAD();
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/* save thread context */
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cont->saved_thread = *th;
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}
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static rb_context_t *
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cont_new(VALUE klass)
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{
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rb_context_t *cont;
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volatile VALUE contval;
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contval = Data_Make_Struct(klass, rb_context_t, cont_mark, cont_free, cont);
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cont->self = contval;
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cont_init(cont);
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return cont;
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}
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void rb_vm_stack_to_heap(rb_thread_t *th);
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static VALUE
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cont_capture(volatile int *stat)
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{
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rb_context_t *cont;
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rb_thread_t *th = GET_THREAD(), *sth;
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volatile VALUE contval;
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rb_vm_stack_to_heap(th);
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cont = cont_new(rb_cContinuation);
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contval = cont->self;
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sth = &cont->saved_thread;
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#ifdef CAPTURE_JUST_VALID_VM_STACK
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cont->vm_stack_slen = th->cfp->sp + th->mark_stack_len - th->stack;
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cont->vm_stack_clen = th->stack + th->stack_size - (VALUE*)th->cfp;
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cont->vm_stack = ALLOC_N(VALUE, cont->vm_stack_slen + cont->vm_stack_clen);
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MEMCPY(cont->vm_stack, th->stack, VALUE, cont->vm_stack_slen);
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MEMCPY(cont->vm_stack + cont->vm_stack_slen, (VALUE*)th->cfp, VALUE, cont->vm_stack_clen);
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#else
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cont->vm_stack = ALLOC_N(VALUE, th->stack_size);
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MEMCPY(cont->vm_stack, th->stack, VALUE, th->stack_size);
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#endif
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sth->stack = 0;
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cont_save_machine_stack(th, cont);
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if (ruby_setjmp(cont->jmpbuf)) {
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VALUE value;
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value = cont->value;
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cont->value = Qnil;
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*stat = 1;
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return value;
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}
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else {
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*stat = 0;
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return cont->self;
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}
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}
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NOINLINE(NORETURN(static void cont_restore_1(rb_context_t *)));
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static void
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cont_restore_1(rb_context_t *cont)
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{
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rb_thread_t *th = GET_THREAD(), *sth = &cont->saved_thread;
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/* restore thread context */
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if (cont->type == CONTINUATION_CONTEXT) {
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/* continuation */
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VALUE fib;
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th->fiber = sth->fiber;
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fib = th->fiber ? th->fiber : th->root_fiber;
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if (fib) {
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rb_context_t *fcont;
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GetContPtr(fib, fcont);
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th->stack_size = fcont->saved_thread.stack_size;
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th->stack = fcont->saved_thread.stack;
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}
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#ifdef CAPTURE_JUST_VALID_VM_STACK
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MEMCPY(th->stack, cont->vm_stack, VALUE, cont->vm_stack_slen);
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MEMCPY(th->stack + sth->stack_size - cont->vm_stack_clen,
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cont->vm_stack + cont->vm_stack_slen, VALUE, cont->vm_stack_clen);
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#else
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MEMCPY(th->stack, cont->vm_stack, VALUE, sth->stack_size);
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#endif
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}
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else {
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/* fiber */
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th->stack = sth->stack;
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th->stack_size = sth->stack_size;
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th->local_storage = sth->local_storage;
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th->fiber = cont->self;
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}
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th->cfp = sth->cfp;
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th->safe_level = sth->safe_level;
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th->raised_flag = sth->raised_flag;
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th->state = sth->state;
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th->status = sth->status;
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th->tag = sth->tag;
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th->trap_tag = sth->trap_tag;
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th->errinfo = sth->errinfo;
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th->first_proc = sth->first_proc;
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/* restore machine stack */
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#ifdef _M_AMD64
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{
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/* workaround for x64 SEH */
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jmp_buf buf;
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setjmp(buf);
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((_JUMP_BUFFER*)(&cont->jmpbuf))->Frame =
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((_JUMP_BUFFER*)(&buf))->Frame;
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}
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#endif
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if (cont->machine_stack_src) {
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FLUSH_REGISTER_WINDOWS;
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MEMCPY(cont->machine_stack_src, cont->machine_stack,
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VALUE, cont->machine_stack_size);
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}
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#ifdef __ia64
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if (cont->machine_register_stack_src) {
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MEMCPY(cont->machine_register_stack_src, cont->machine_register_stack,
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VALUE, cont->machine_register_stack_size);
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}
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#endif
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ruby_longjmp(cont->jmpbuf, 1);
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}
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NORETURN(NOINLINE(static void cont_restore_0(rb_context_t *, VALUE *)));
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#ifdef __ia64
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#define C(a) rse_##a##0, rse_##a##1, rse_##a##2, rse_##a##3, rse_##a##4
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#define E(a) rse_##a##0= rse_##a##1= rse_##a##2= rse_##a##3= rse_##a##4
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static volatile int C(a), C(b), C(c), C(d), C(e);
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static volatile int C(f), C(g), C(h), C(i), C(j);
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static volatile int C(k), C(l), C(m), C(n), C(o);
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static volatile int C(p), C(q), C(r), C(s), C(t);
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#if 0
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{/* the above lines make cc-mode.el confused so much */}
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#endif
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int rb_dummy_false = 0;
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NORETURN(NOINLINE(static void register_stack_extend(rb_context_t *, VALUE *, VALUE *)));
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static void
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register_stack_extend(rb_context_t *cont, VALUE *vp, VALUE *curr_bsp)
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{
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if (rb_dummy_false) {
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/* use registers as much as possible */
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E(a) = E(b) = E(c) = E(d) = E(e) =
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E(f) = E(g) = E(h) = E(i) = E(j) =
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E(k) = E(l) = E(m) = E(n) = E(o) =
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E(p) = E(q) = E(r) = E(s) = E(t) = 0;
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E(a) = E(b) = E(c) = E(d) = E(e) =
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E(f) = E(g) = E(h) = E(i) = E(j) =
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E(k) = E(l) = E(m) = E(n) = E(o) =
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E(p) = E(q) = E(r) = E(s) = E(t) = 0;
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}
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if (curr_bsp < cont->machine_register_stack_src+cont->machine_register_stack_size) {
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register_stack_extend(cont, vp, (VALUE*)rb_ia64_bsp());
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}
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cont_restore_0(cont, vp);
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}
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#undef C
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#undef E
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#endif
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static void
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cont_restore_0(rb_context_t *cont, VALUE *addr_in_prev_frame)
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{
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if (cont->machine_stack_src) {
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#ifdef HAVE_ALLOCA
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#define STACK_PAD_SIZE 1
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#else
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#define STACK_PAD_SIZE 1024
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#endif
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VALUE space[STACK_PAD_SIZE];
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#if !STACK_GROW_DIRECTION
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if (addr_in_prev_frame > &space[0]) {
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/* Stack grows downward */
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#endif
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#if STACK_GROW_DIRECTION <= 0
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volatile VALUE *const end = cont->machine_stack_src;
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if (&space[0] > end) {
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# ifdef HAVE_ALLOCA
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volatile VALUE *sp = ALLOCA_N(VALUE, &space[0] - end);
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(void)sp;
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# else
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cont_restore_0(cont, &space[0]);
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# endif
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}
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#endif
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#if !STACK_GROW_DIRECTION
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}
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else {
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/* Stack grows upward */
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#endif
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#if STACK_GROW_DIRECTION >= 0
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volatile VALUE *const end = cont->machine_stack_src + cont->machine_stack_size;
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if (&space[STACK_PAD_SIZE] < end) {
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# ifdef HAVE_ALLOCA
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volatile VALUE *sp = ALLOCA_N(VALUE, end - &space[STACK_PAD_SIZE]);
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(void)sp;
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# else
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cont_restore_0(cont, &space[STACK_PAD_SIZE-1]);
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# endif
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}
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#endif
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#if !STACK_GROW_DIRECTION
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}
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#endif
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}
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cont_restore_1(cont);
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}
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#ifdef __ia64
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#define cont_restore_0(cont, vp) register_stack_extend(cont, vp, (VALUE*)rb_ia64_bsp());
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#endif
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/*
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* Document-class: Continuation
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*
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* Continuation objects are generated by
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* <code>Kernel#callcc</code>. They hold a return address and execution
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* context, allowing a nonlocal return to the end of the
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* <code>callcc</code> block from anywhere within a program.
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* Continuations are somewhat analogous to a structured version of C's
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* <code>setjmp/longjmp</code> (although they contain more state, so
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* you might consider them closer to threads).
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*
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* For instance:
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*
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* arr = [ "Freddie", "Herbie", "Ron", "Max", "Ringo" ]
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* callcc{|$cc|}
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* puts(message = arr.shift)
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* $cc.call unless message =~ /Max/
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*
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* <em>produces:</em>
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*
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* Freddie
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* Herbie
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* Ron
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* Max
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*
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* This (somewhat contrived) example allows the inner loop to abandon
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* processing early:
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*
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* callcc {|cont|
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* for i in 0..4
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* print "\n#{i}: "
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* for j in i*5...(i+1)*5
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* cont.call() if j == 17
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* printf "%3d", j
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* end
|
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* end
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* }
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* print "\n"
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*
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* <em>produces:</em>
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*
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* 0: 0 1 2 3 4
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* 1: 5 6 7 8 9
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* 2: 10 11 12 13 14
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* 3: 15 16
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*/
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/*
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* call-seq:
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* callcc {|cont| block } => obj
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*
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* Generates a <code>Continuation</code> object, which it passes to the
|
|
* associated block. Performing a <em>cont</em><code>.call</code> will
|
|
* cause the <code>callcc</code> to return (as will falling through the
|
|
* end of the block). The value returned by the <code>callcc</code> is
|
|
* the value of the block, or the value passed to
|
|
* <em>cont</em><code>.call</code>. See class <code>Continuation</code>
|
|
* for more details. Also see <code>Kernel::throw</code> for
|
|
* an alternative mechanism for unwinding a call stack.
|
|
*/
|
|
|
|
static VALUE
|
|
rb_callcc(VALUE self)
|
|
{
|
|
volatile int called;
|
|
volatile VALUE val = cont_capture(&called);
|
|
|
|
if (called) {
|
|
return val;
|
|
}
|
|
else {
|
|
return rb_yield(val);
|
|
}
|
|
}
|
|
|
|
static VALUE
|
|
make_passing_arg(int argc, VALUE *argv)
|
|
{
|
|
switch(argc) {
|
|
case 0:
|
|
return Qnil;
|
|
case 1:
|
|
return argv[0];
|
|
default:
|
|
return rb_ary_new4(argc, argv);
|
|
}
|
|
}
|
|
|
|
/*
|
|
* call-seq:
|
|
* cont.call(args, ...)
|
|
* cont[args, ...]
|
|
*
|
|
* Invokes the continuation. The program continues from the end of the
|
|
* <code>callcc</code> block. If no arguments are given, the original
|
|
* <code>callcc</code> returns <code>nil</code>. If one argument is
|
|
* given, <code>callcc</code> returns it. Otherwise, an array
|
|
* containing <i>args</i> is returned.
|
|
*
|
|
* callcc {|cont| cont.call } #=> nil
|
|
* callcc {|cont| cont.call 1 } #=> 1
|
|
* callcc {|cont| cont.call 1, 2, 3 } #=> [1, 2, 3]
|
|
*/
|
|
|
|
static VALUE
|
|
rb_cont_call(int argc, VALUE *argv, VALUE contval)
|
|
{
|
|
rb_context_t *cont;
|
|
rb_thread_t *th = GET_THREAD();
|
|
GetContPtr(contval, cont);
|
|
|
|
if (cont->saved_thread.self != th->self) {
|
|
rb_raise(rb_eRuntimeError, "continuation called across threads");
|
|
}
|
|
if (cont->saved_thread.trap_tag != th->trap_tag) {
|
|
rb_raise(rb_eRuntimeError, "continuation called across trap");
|
|
}
|
|
if (cont->saved_thread.fiber) {
|
|
rb_context_t *fcont;
|
|
GetContPtr(cont->saved_thread.fiber, fcont);
|
|
|
|
if (th->fiber != cont->saved_thread.fiber) {
|
|
rb_raise(rb_eRuntimeError, "continuation called across fiber");
|
|
}
|
|
}
|
|
|
|
cont->argc = argc;
|
|
cont->value = make_passing_arg(argc, argv);
|
|
|
|
cont_restore_0(cont, &contval);
|
|
return Qnil; /* unreachable */
|
|
}
|
|
|
|
/*********/
|
|
/* fiber */
|
|
/*********/
|
|
|
|
/*
|
|
* Document-class: Fiber
|
|
*
|
|
* Fibers are primitives for implementing light weight cooperative
|
|
* concurrency in Ruby. Basically they are a means of creating code blocks
|
|
* that can be paused and resumed, much like threads. The main difference
|
|
* is that they are never preempted and that the scheduling must be done by
|
|
* the programmer and not the VM.
|
|
*
|
|
* As opposed to other stackless light weight concurrency models, each fiber
|
|
* comes with a small 4KB stack. This enables the fiber to be paused from deeply
|
|
* nested function calls within the fiber block.
|
|
*
|
|
* When a fiber is created it will not run automatically. Rather it must be
|
|
* be explicitly asked to run using the <code>Fiber#resume</code> method.
|
|
* The code running inside the fiber can give up control by calling
|
|
* <code>Fiber.yield</code> in which case it yields control back to caller
|
|
* (the caller of the <code>Fiber#resume</code>).
|
|
*
|
|
* Upon yielding or termination the Fiber returns the value of the last
|
|
* executed expression
|
|
*
|
|
* For instance:
|
|
*
|
|
* fiber = Fiber.new do
|
|
* Fiber.yield 1
|
|
* 2
|
|
* end
|
|
*
|
|
* puts fiber.resume
|
|
* puts fiber.resume
|
|
* puts fiber.resume
|
|
*
|
|
* <em>produces</em>
|
|
*
|
|
* 1
|
|
* 2
|
|
* FiberError: dead fiber called
|
|
*
|
|
* The <code>Fiber#resume</code> method accepts an arbitary number of
|
|
* parameters, if it is the first call to <code>resume</code> then they
|
|
* will be passed as block arguments. Otherwise they will be the return
|
|
* value of the call to <code>Fiber.yield</code>
|
|
*
|
|
* Example:
|
|
*
|
|
* fiber = Fiber.new do |first|
|
|
* second = Fiber.yield first + 2
|
|
* end
|
|
*
|
|
* puts fiber.resume 10
|
|
* puts fiber.resume 14
|
|
* puts fiber.resume 18
|
|
*
|
|
* <em>produces</em>
|
|
*
|
|
* 12
|
|
* 14
|
|
* FiberError: dead fiber called
|
|
*
|
|
*/
|
|
|
|
#define FIBER_VM_STACK_SIZE (4 * 1024)
|
|
|
|
static VALUE
|
|
fiber_alloc(VALUE klass)
|
|
{
|
|
return Data_Wrap_Struct(klass, fiber_mark, fiber_free, 0);
|
|
}
|
|
|
|
static rb_fiber_t*
|
|
fiber_t_alloc(VALUE fibval)
|
|
{
|
|
rb_fiber_t *fib = ALLOC(rb_fiber_t);
|
|
|
|
memset(fib, 0, sizeof(rb_fiber_t));
|
|
fib->cont.self = fibval;
|
|
fib->cont.type = FIBER_CONTEXT;
|
|
cont_init(&fib->cont);
|
|
fib->prev = Qnil;
|
|
fib->status = CREATED;
|
|
|
|
DATA_PTR(fibval) = fib;
|
|
|
|
return fib;
|
|
}
|
|
|
|
static VALUE
|
|
fiber_init(VALUE fibval, VALUE proc)
|
|
{
|
|
rb_fiber_t *fib = fiber_t_alloc(fibval);
|
|
rb_context_t *cont = &fib->cont;
|
|
rb_thread_t *th = &cont->saved_thread;
|
|
|
|
fiber_link_join(fib);
|
|
|
|
/* initialize cont */
|
|
cont->vm_stack = 0;
|
|
|
|
th->stack = 0;
|
|
th->stack_size = FIBER_VM_STACK_SIZE;
|
|
th->stack = ALLOC_N(VALUE, th->stack_size);
|
|
|
|
th->cfp = (void *)(th->stack + th->stack_size);
|
|
th->cfp--;
|
|
th->cfp->pc = 0;
|
|
th->cfp->sp = th->stack + 1;
|
|
th->cfp->bp = 0;
|
|
th->cfp->lfp = th->stack;
|
|
*th->cfp->lfp = 0;
|
|
th->cfp->dfp = th->stack;
|
|
th->cfp->self = Qnil;
|
|
th->cfp->flag = 0;
|
|
th->cfp->iseq = 0;
|
|
th->cfp->proc = 0;
|
|
th->cfp->block_iseq = 0;
|
|
th->tag = 0;
|
|
th->local_storage = st_init_numtable();
|
|
|
|
th->first_proc = proc;
|
|
|
|
MEMCPY(&cont->jmpbuf, &th->root_jmpbuf, rb_jmpbuf_t, 1);
|
|
|
|
return fibval;
|
|
}
|
|
|
|
static VALUE
|
|
rb_fiber_init(VALUE fibval)
|
|
{
|
|
return fiber_init(fibval, rb_block_proc());
|
|
}
|
|
|
|
VALUE
|
|
rb_fiber_new(VALUE (*func)(ANYARGS), VALUE obj)
|
|
{
|
|
return fiber_init(fiber_alloc(rb_cFiber), rb_proc_new(func, obj));
|
|
}
|
|
|
|
static VALUE
|
|
return_fiber(void)
|
|
{
|
|
rb_fiber_t *fib;
|
|
VALUE curr = rb_fiber_current();
|
|
GetFiberPtr(curr, fib);
|
|
|
|
if (fib->prev == Qnil) {
|
|
rb_thread_t *th = GET_THREAD();
|
|
|
|
if (th->root_fiber != curr) {
|
|
return th->root_fiber;
|
|
}
|
|
else {
|
|
rb_raise(rb_eFiberError, "can't yield from root fiber");
|
|
}
|
|
}
|
|
else {
|
|
VALUE prev = fib->prev;
|
|
fib->prev = Qnil;
|
|
return prev;
|
|
}
|
|
}
|
|
|
|
VALUE rb_fiber_transfer(VALUE fib, int argc, VALUE *argv);
|
|
|
|
static void
|
|
rb_fiber_terminate(rb_fiber_t *fib)
|
|
{
|
|
VALUE value = fib->cont.value;
|
|
fib->status = TERMINATED;
|
|
rb_fiber_transfer(return_fiber(), 1, &value);
|
|
}
|
|
|
|
void
|
|
rb_fiber_start(void)
|
|
{
|
|
rb_thread_t *th = GET_THREAD();
|
|
rb_fiber_t *fib;
|
|
rb_context_t *cont;
|
|
rb_proc_t *proc;
|
|
int state;
|
|
|
|
GetFiberPtr(th->fiber, fib);
|
|
cont = &fib->cont;
|
|
|
|
TH_PUSH_TAG(th);
|
|
if ((state = EXEC_TAG()) == 0) {
|
|
int argc;
|
|
VALUE *argv, args;
|
|
GetProcPtr(cont->saved_thread.first_proc, proc);
|
|
args = cont->value;
|
|
argv = (argc = cont->argc) > 1 ? RARRAY_PTR(args) : &args;
|
|
cont->value = Qnil;
|
|
th->errinfo = Qnil;
|
|
th->local_lfp = proc->block.lfp;
|
|
th->local_svar = Qnil;
|
|
|
|
fib->status = RUNNING;
|
|
cont->value = rb_vm_invoke_proc(th, proc, proc->block.self, argc, argv, 0);
|
|
}
|
|
TH_POP_TAG();
|
|
|
|
if (state) {
|
|
if (TAG_RAISE) {
|
|
th->thrown_errinfo = th->errinfo;
|
|
}
|
|
else {
|
|
th->thrown_errinfo =
|
|
rb_vm_make_jump_tag_but_local_jump(state, th->errinfo);
|
|
}
|
|
RUBY_VM_SET_INTERRUPT(th);
|
|
}
|
|
|
|
rb_fiber_terminate(fib);
|
|
rb_bug("rb_fiber_start: unreachable");
|
|
}
|
|
|
|
static rb_fiber_t *
|
|
root_fiber_alloc(rb_thread_t *th)
|
|
{
|
|
rb_fiber_t *fib;
|
|
|
|
/* no need to allocate vm stack */
|
|
fib = fiber_t_alloc(fiber_alloc(rb_cFiber));
|
|
fib->cont.type = ROOT_FIBER_CONTEXT;
|
|
fib->prev_fiber = fib->next_fiber = fib;
|
|
|
|
return fib;
|
|
}
|
|
|
|
VALUE
|
|
rb_fiber_current(void)
|
|
{
|
|
rb_thread_t *th = GET_THREAD();
|
|
if (th->fiber == 0) {
|
|
/* save root */
|
|
rb_fiber_t *fib = root_fiber_alloc(th);
|
|
th->root_fiber = th->fiber = fib->cont.self;
|
|
}
|
|
return th->fiber;
|
|
}
|
|
|
|
static VALUE
|
|
fiber_store(rb_fiber_t *next_fib)
|
|
{
|
|
rb_thread_t *th = GET_THREAD();
|
|
rb_fiber_t *fib;
|
|
|
|
if (th->fiber) {
|
|
GetFiberPtr(th->fiber, fib);
|
|
fib->cont.saved_thread = *th;
|
|
}
|
|
else {
|
|
/* create current fiber */
|
|
fib = root_fiber_alloc(th);
|
|
th->root_fiber = th->fiber = fib->cont.self;
|
|
}
|
|
|
|
cont_save_machine_stack(th, &fib->cont);
|
|
|
|
if (ruby_setjmp(fib->cont.jmpbuf)) {
|
|
/* restored */
|
|
GetFiberPtr(th->fiber, fib);
|
|
return fib->cont.value;
|
|
}
|
|
else {
|
|
return Qundef;
|
|
}
|
|
}
|
|
|
|
static inline VALUE
|
|
fiber_switch(VALUE fibval, int argc, VALUE *argv, int is_resume)
|
|
{
|
|
VALUE value;
|
|
rb_fiber_t *fib;
|
|
rb_context_t *cont;
|
|
rb_thread_t *th = GET_THREAD();
|
|
|
|
GetFiberPtr(fibval, fib);
|
|
cont = &fib->cont;
|
|
|
|
if (cont->saved_thread.self != th->self) {
|
|
rb_raise(rb_eFiberError, "fiber called across threads");
|
|
}
|
|
else if (cont->saved_thread.trap_tag != th->trap_tag) {
|
|
rb_raise(rb_eFiberError, "fiber called across trap");
|
|
}
|
|
else if (fib->status == TERMINATED) {
|
|
rb_raise(rb_eFiberError, "dead fiber called");
|
|
}
|
|
|
|
if (is_resume) {
|
|
fib->prev = rb_fiber_current();
|
|
}
|
|
|
|
cont->argc = argc;
|
|
cont->value = make_passing_arg(argc, argv);
|
|
|
|
if ((value = fiber_store(fib)) == Qundef) {
|
|
cont_restore_0(&fib->cont, &value);
|
|
rb_bug("rb_fiber_resume: unreachable");
|
|
}
|
|
|
|
RUBY_VM_CHECK_INTS();
|
|
|
|
return value;
|
|
}
|
|
|
|
VALUE
|
|
rb_fiber_transfer(VALUE fib, int argc, VALUE *argv)
|
|
{
|
|
return fiber_switch(fib, argc, argv, 0);
|
|
}
|
|
|
|
VALUE
|
|
rb_fiber_resume(VALUE fibval, int argc, VALUE *argv)
|
|
{
|
|
rb_fiber_t *fib;
|
|
GetFiberPtr(fibval, fib);
|
|
|
|
if (fib->prev != Qnil) {
|
|
rb_raise(rb_eFiberError, "double resume");
|
|
}
|
|
|
|
return fiber_switch(fibval, argc, argv, 1);
|
|
}
|
|
|
|
VALUE
|
|
rb_fiber_yield(int argc, VALUE *argv)
|
|
{
|
|
return rb_fiber_transfer(return_fiber(), argc, argv);
|
|
}
|
|
|
|
/*
|
|
* call-seq:
|
|
* fiber.alive? -> true or false
|
|
*
|
|
* Returns true if the fiber can still be resumed (or transferred to).
|
|
* After finishing execution of the fiber block this method will always
|
|
* return false.
|
|
*/
|
|
VALUE
|
|
rb_fiber_alive_p(VALUE fibval)
|
|
{
|
|
rb_fiber_t *fib;
|
|
GetFiberPtr(fibval, fib);
|
|
return fib->status != TERMINATED;
|
|
}
|
|
|
|
/*
|
|
* call-seq:
|
|
* fiber.resume(args, ...) -> obj
|
|
*
|
|
* Resumes the fiber from the point at which the last <code>Fiber.yield</code>
|
|
* was called, or starts running it if it is the first call to
|
|
* <code>resume</code>. Arguments passed to resume will be the value of
|
|
* the <code>Fiber.yield</code> expression or will be passed as block
|
|
* parameters to the fiber's block if this is the first <code>resume</code>.
|
|
*
|
|
* Alternatively, when resume is called it evaluates to the arguments passed
|
|
* to the next <code>Fiber.yield</code> statement inside the fiber's block
|
|
* or to the block value if it runs to completion without any
|
|
* <code>Fiber.yield</code>
|
|
*/
|
|
static VALUE
|
|
rb_fiber_m_resume(int argc, VALUE *argv, VALUE fib)
|
|
{
|
|
return rb_fiber_resume(fib, argc, argv);
|
|
}
|
|
|
|
/*
|
|
* call-seq:
|
|
* fiber.transfer(args, ...) -> obj
|
|
*
|
|
* Transfer control to another fiber, resuming it from where it last
|
|
* stopped or starting it if it was not resumed before. The calling
|
|
* fiber will be suspended much like in a call to <code>Fiber.yield</code>.
|
|
*
|
|
* The fiber which recieves the transfer call is treats it much like
|
|
* a resume call. Arguments passed to transfer are treated like those
|
|
* passed to resume.
|
|
*
|
|
* You cannot resume a fiber that transferred control to another one.
|
|
* This will cause a double resume error. You need to transfer control
|
|
* back to this fiber before it can yield and resume.
|
|
*/
|
|
static VALUE
|
|
rb_fiber_m_transfer(int argc, VALUE *argv, VALUE fib)
|
|
{
|
|
return rb_fiber_transfer(fib, argc, argv);
|
|
}
|
|
|
|
/*
|
|
* call-seq:
|
|
* Fiber.yield(args, ...) -> obj
|
|
*
|
|
* Yields control back to the context that resumed the fiber, passing
|
|
* along any arguments that were passed to it. The fiber will resume
|
|
* processing at this point when <code>resume</code> is called next.
|
|
* Any arguments passed to the next <code>resume</code> will be the
|
|
* value that this <code>Fiber.yield</code> expression evaluates to.
|
|
*/
|
|
static VALUE
|
|
rb_fiber_s_yield(int argc, VALUE *argv, VALUE klass)
|
|
{
|
|
return rb_fiber_yield(argc, argv);
|
|
}
|
|
|
|
/*
|
|
* call-seq:
|
|
* Fiber.current() -> fiber
|
|
*
|
|
* Returns the current fiber. You need to <code>require 'fiber'</code>
|
|
* before using this method. If you are not running in the context of
|
|
* a fiber this method will return the root fiber.
|
|
*/
|
|
static VALUE
|
|
rb_fiber_s_current(VALUE klass)
|
|
{
|
|
return rb_fiber_current();
|
|
}
|
|
|
|
void
|
|
Init_Cont(void)
|
|
{
|
|
rb_cFiber = rb_define_class("Fiber", rb_cObject);
|
|
rb_define_alloc_func(rb_cFiber, fiber_alloc);
|
|
rb_eFiberError = rb_define_class("FiberError", rb_eStandardError);
|
|
rb_define_singleton_method(rb_cFiber, "yield", rb_fiber_s_yield, -1);
|
|
rb_define_method(rb_cFiber, "initialize", rb_fiber_init, 0);
|
|
rb_define_method(rb_cFiber, "resume", rb_fiber_m_resume, -1);
|
|
}
|
|
|
|
void
|
|
ruby_Init_Continuation_body(void)
|
|
{
|
|
rb_cContinuation = rb_define_class("Continuation", rb_cObject);
|
|
rb_undef_alloc_func(rb_cContinuation);
|
|
rb_undef_method(CLASS_OF(rb_cContinuation), "new");
|
|
rb_define_method(rb_cContinuation, "call", rb_cont_call, -1);
|
|
rb_define_method(rb_cContinuation, "[]", rb_cont_call, -1);
|
|
rb_define_global_function("callcc", rb_callcc, 0);
|
|
}
|
|
|
|
void
|
|
ruby_Init_Fiber_as_Coroutine(void)
|
|
{
|
|
rb_define_method(rb_cFiber, "transfer", rb_fiber_m_transfer, -1);
|
|
rb_define_method(rb_cFiber, "alive?", rb_fiber_alive_p, 0);
|
|
rb_define_singleton_method(rb_cFiber, "current", rb_fiber_s_current, 0);
|
|
}
|