1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
|
#if !defined __lanes_private_h__
#define __lanes_private_h__ 1
#include "uniquekey.h"
/*
* Lane cancellation request modes
*/
enum e_cancel_request
{
CANCEL_NONE, // no pending cancel request
CANCEL_SOFT, // user wants the lane to cancel itself manually on cancel_test()
CANCEL_HARD // user wants the lane to be interrupted (meaning code won't return from those functions) from inside linda:send/receive calls
};
// NOTE: values to be changed by either thread, during execution, without
// locking, are marked "volatile"
//
struct s_Lane
{
THREAD_T thread;
//
// M: sub-thread OS thread
// S: not used
char const* debug_name;
lua_State* L;
Universe* U;
//
// M: prepares the state, and reads results
// S: while S is running, M must keep out of modifying the state
volatile enum e_status status;
//
// M: sets to PENDING (before launching)
// S: updates -> RUNNING/WAITING -> DONE/ERROR_ST/CANCELLED
SIGNAL_T* volatile waiting_on;
//
// When status is WAITING, points on the linda's signal the thread waits on, else NULL
volatile enum e_cancel_request cancel_request;
//
// M: sets to FALSE, flags TRUE for cancel request
// S: reads to see if cancel is requested
#if THREADWAIT_METHOD == THREADWAIT_CONDVAR
SIGNAL_T done_signal;
//
// M: Waited upon at lane ending (if Posix with no PTHREAD_TIMEDJOIN)
// S: sets the signal once cancellation is noticed (avoids a kill)
MUTEX_T done_lock;
//
// Lock required by 'done_signal' condition variable, protecting
// lane status changes to DONE/ERROR_ST/CANCELLED.
#endif // THREADWAIT_METHOD == THREADWAIT_CONDVAR
volatile enum
{
NORMAL, // normal master side state
KILLED // issued an OS kill
} mstatus;
//
// M: sets to NORMAL, if issued a kill changes to KILLED
// S: not used
struct s_Lane* volatile selfdestruct_next;
//
// M: sets to non-NULL if facing lane handle '__gc' cycle but the lane
// is still running
// S: cleans up after itself if non-NULL at lane exit
#if HAVE_LANE_TRACKING
struct s_Lane* volatile tracking_next;
#endif // HAVE_LANE_TRACKING
//
// For tracking only
};
typedef struct s_Lane Lane;
// To allow free-running threads (longer lifespan than the handle's)
// 'Lane' are malloc/free'd and the handle only carries a pointer.
// This is not deep userdata since the handle's not portable among lanes.
//
#define lua_toLane( L, i) (*((Lane**) luaL_checkudata( L, i, "Lane")))
// crc64/we of string "CANCEL_ERROR" generated at http://www.nitrxgen.net/hashgen/
static DECLARE_CONST_UNIQUE_KEY(CANCEL_ERROR, 0xe97d41626cc97577); // 'cancel_error' sentinel
// crc64/we of string "CANCEL_TEST_KEY" generated at http://www.nitrxgen.net/hashgen/
static DECLARE_CONST_UNIQUE_KEY(CANCEL_TEST_KEY, 0xe66f5960c57d133a); // used as registry key
static inline Lane* get_lane_from_registry( lua_State* L)
{
Lane* s;
STACK_GROW( L, 1);
STACK_CHECK( L);
push_unique_key( L, CANCEL_TEST_KEY);
lua_rawget( L, LUA_REGISTRYINDEX);
s = lua_touserdata( L, -1); // lightuserdata (true 's_lane' pointer) / nil
lua_pop( L, 1);
STACK_END( L, 0);
return s;
}
static inline int cancel_error( lua_State* L)
{
STACK_GROW( L, 1);
push_unique_key( L, CANCEL_ERROR); // special error value
return lua_error( L); // doesn't return
}
#endif // __lanes_private_h__
|
