zend_fibers.h

/*
 +----------------------------------------------------------------------+
 | Zend Engine |
 +----------------------------------------------------------------------+
 | Copyright (c) Zend Technologies Ltd. (http://www.zend.com) |
 +----------------------------------------------------------------------+
 | This source file is subject to version 2.00 of the Zend license, |
 | that is bundled with this package in the file LICENSE, and is |
 | available through the world-wide-web at the following url: |
 | http://www.zend.com/license/2_00.txt. |
 | If you did not receive a copy of the Zend license and are unable to |
 | obtain it through the world-wide-web, please send a note to |
 | license@zend.com so we can mail you a copy immediately. |
 +----------------------------------------------------------------------+
 | Authors: Aaron Piotrowski <aaron@trowski.com> |
 | Martin Schröder <m.schroeder2007@gmail.com> |
 +----------------------------------------------------------------------+
*/

#ifndefZEND_FIBERS_H
#defineZEND_FIBERS_H

#include"zend_API.h"
#include"zend_types.h"

#defineZEND_FIBER_GUARD_PAGES 1

#defineZEND_FIBER_DEFAULT_C_STACK_SIZE (4096 * (((sizeof(void *)) < 8) ? 256 : 512))
#defineZEND_FIBER_VM_STACK_SIZE (1024 * sizeof(zval))

BEGIN_EXTERN_C()

typedefenum {
ZEND_FIBER_STATUS_INIT,
ZEND_FIBER_STATUS_RUNNING,
ZEND_FIBER_STATUS_SUSPENDED,
ZEND_FIBER_STATUS_DEAD,
} zend_fiber_status;

typedefenum {
ZEND_FIBER_FLAG_THREW=1 << 0,
ZEND_FIBER_FLAG_BAILOUT=1 << 1,
ZEND_FIBER_FLAG_DESTROYED=1 << 2,
} zend_fiber_flag;

typedefenum {
ZEND_FIBER_TRANSFER_FLAG_ERROR=1 << 0,
ZEND_FIBER_TRANSFER_FLAG_BAILOUT=1 << 1
} zend_fiber_transfer_flag;

voidzend_register_fiber_ce(void);
voidzend_fiber_init(void);
voidzend_fiber_shutdown(void);

externZEND_APIzend_class_entry*zend_ce_fiber;

typedefstruct_zend_fiber_stackzend_fiber_stack;

/* Encapsulates data needed for a context switch. */
typedefstruct_zend_fiber_transfer {
/* Fiber that will be switched to / has resumed us. */
zend_fiber_context*context;

/* Value to that should be send to (or was received from) a fiber. */
zvalvalue;

/* Bitmask of flags defined in enum zend_fiber_transfer_flag. */
uint8_tflags;
} zend_fiber_transfer;

/* Coroutine functions must populate the given transfer with a new context
 * and (optional) data before they return. */
typedefvoid (*zend_fiber_coroutine)(zend_fiber_transfer*transfer);
typedefvoid (*zend_fiber_clean)(zend_fiber_context*context);

struct_zend_fiber_context {
/* Pointer to boost.context or ucontext_t data. */
void*handle;

/* Pointer that identifies the fiber type. */
void*kind;

/* Entrypoint function of the fiber. */
zend_fiber_coroutinefunction;

/* Cleanup function for fiber. */
zend_fiber_cleancleanup;

/* Assigned C stack. */
zend_fiber_stack*stack;

/* Fiber status. */
zend_fiber_statusstatus;

/* Observer state */
zend_execute_data*top_observed_frame;

/* Reserved for extensions */
void*reserved[ZEND_MAX_RESERVED_RESOURCES];
};

struct_zend_fiber {
/* PHP object handle. */
zend_objectstd;

/* Flags are defined in enum zend_fiber_flag. */
uint8_tflags;

/* Native C fiber context. */
zend_fiber_contextcontext;

/* Fiber that resumed us. */
zend_fiber_context*caller;

/* Fiber that suspended us. */
zend_fiber_context*previous;

/* Callback and info / cache to be used when fiber is started. */
zend_fcall_infofci;
zend_fcall_info_cachefci_cache;

/* Current Zend VM execute data being run by the fiber. */
zend_execute_data*execute_data;

/* Frame on the bottom of the fiber vm stack. */
zend_execute_data*stack_bottom;

/* Active fiber vm stack. */
zend_vm_stackvm_stack;

/* Storage for fiber return value. */
zvalresult;
};

/* These functions may be used to create custom fiber objects using the bundled fiber switching context. */
ZEND_APIzend_resultzend_fiber_init_context(zend_fiber_context*context, void*kind, zend_fiber_coroutinecoroutine, size_tstack_size);
ZEND_APIvoidzend_fiber_destroy_context(zend_fiber_context*context);
ZEND_APIvoidzend_fiber_switch_context(zend_fiber_transfer*transfer);
#ifdefZEND_CHECK_STACK_LIMIT
ZEND_APIvoid*zend_fiber_stack_limit(zend_fiber_stack*stack);
ZEND_APIvoid*zend_fiber_stack_base(zend_fiber_stack*stack);
#endif/* ZEND_CHECK_STACK_LIMIT */

ZEND_APIvoidzend_fiber_switch_block(void);
ZEND_APIvoidzend_fiber_switch_unblock(void);
ZEND_APIboolzend_fiber_switch_blocked(void);

END_EXTERN_C()

staticzend_always_inlinezend_fiber*zend_fiber_from_context(zend_fiber_context*context)
{
ZEND_ASSERT(context->kind==zend_ce_fiber&&"Fiber context does not belong to a Zend fiber");

return (zend_fiber*)(((char*) context) -XtOffsetOf(zend_fiber, context));
}

staticzend_always_inlinezend_fiber_context*zend_fiber_get_context(zend_fiber*fiber)
{
return&fiber->context;
}

#endif