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
|
/*
libco.ucontext (2008-01-28)
author: Nach
license: public domain
*/
/*
* WARNING: the overhead of POSIX ucontext is very high,
* assembly versions of libco or libco_sjlj should be much faster
*
* This library only exists for two reasons:
* 1 - as an initial test for the viability of a ucontext implementation
* 2 - to demonstrate the power and speed of libco over existing implementations,
* such as pth (which defaults to wrapping ucontext on unix targets)
*
* Use this library only as a *last resort*
*/
#define LIBCO_C
#include "libco.h"
#include <stdlib.h>
#include <ucontext.h>
#ifdef __cplusplus
extern "C" {
#endif
static thread_local ucontext_t co_primary;
static thread_local ucontext_t *co_running = 0;
cothread_t co_active() {
if(!co_running) co_running = &co_primary;
return (cothread_t)co_running;
}
cothread_t co_create(unsigned int heapsize, void (*coentry)(void)) {
if(!co_running) co_running = &co_primary;
ucontext_t *thread = (ucontext_t*)malloc(sizeof(ucontext_t));
if(thread) {
if((!getcontext(thread) && !(thread->uc_stack.ss_sp = 0)) && (thread->uc_stack.ss_sp = malloc(heapsize))) {
thread->uc_link = co_running;
thread->uc_stack.ss_size = heapsize;
makecontext(thread, coentry, 0);
} else {
co_delete((cothread_t)thread);
thread = 0;
}
}
return (cothread_t)thread;
}
void co_delete(cothread_t cothread) {
if(cothread) {
if(((ucontext_t*)cothread)->uc_stack.ss_sp) { free(((ucontext_t*)cothread)->uc_stack.ss_sp); }
free(cothread);
}
}
void co_switch(cothread_t cothread) {
ucontext_t *old_thread = co_running;
co_running = (ucontext_t*)cothread;
swapcontext(old_thread, co_running);
}
#ifdef __cplusplus
}
#endif
|
