notaz.gp2x.de / pcsx_rearmed.git / blame
| Commit | Line | Data |
|---|---|---|
| 3719602c PC |
1 | /* |
| 2 | libco.ucontext (2008-01-28) | |
| 3 | author: Nach | |
| 4 | license: public domain | |
| 5 | */ | |
| 6 | ||
| 7 | /* | |
| 8 | * WARNING: the overhead of POSIX ucontext is very high, | |
| 9 | * assembly versions of libco or libco_sjlj should be much faster | |
| 10 | * | |
| 11 | * This library only exists for two reasons: | |
| 12 | * 1 - as an initial test for the viability of a ucontext implementation | |
| 13 | * 2 - to demonstrate the power and speed of libco over existing implementations, | |
| 14 | * such as pth (which defaults to wrapping ucontext on unix targets) | |
| 15 | * | |
| 16 | * Use this library only as a *last resort* | |
| 17 | */ | |
| 18 | ||
| 19 | #define LIBCO_C | |
| 20 | #include <libco.h> | |
| 21 | #include <stdlib.h> | |
| 22 | #include <ucontext.h> | |
| 23 | ||
| 24 | #ifdef __cplusplus | |
| 25 | extern "C" { | |
| 26 | #endif | |
| 27 | ||
| 28 | static thread_local ucontext_t co_primary; | |
| 29 | static thread_local ucontext_t *co_running = 0; | |
| 30 | ||
| 31 | cothread_t co_active(void) | |
| 32 | { | |
| 33 | if (!co_running) | |
| 34 | co_running = &co_primary; | |
| 35 | return (cothread_t)co_running; | |
| 36 | } | |
| 37 | ||
| 38 | cothread_t co_create(unsigned int heapsize, void (*coentry)(void)) | |
| 39 | { | |
| 40 | ucontext_t *thread; | |
| 41 | if (!co_running) | |
| 42 | co_running = &co_primary; | |
| 43 | ||
| 44 | if ((thread = (ucontext_t*)malloc(sizeof(ucontext_t)))) | |
| 45 | { | |
| 46 | if ((!getcontext(thread) && !(thread->uc_stack.ss_sp = 0)) && (thread->uc_stack.ss_sp = malloc(heapsize))) | |
| 47 | { | |
| 48 | thread->uc_link = co_running; | |
| 49 | thread->uc_stack.ss_size = heapsize; | |
| 50 | makecontext(thread, coentry, 0); | |
| 51 | } | |
| 52 | else | |
| 53 | { | |
| 54 | co_delete((cothread_t)thread); | |
| 55 | thread = 0; | |
| 56 | } | |
| 57 | } | |
| 58 | return (cothread_t)thread; | |
| 59 | } | |
| 60 | ||
| 61 | void co_delete(cothread_t cothread) | |
| 62 | { | |
| 63 | if (!cothread) | |
| 64 | return; | |
| 65 | ||
| 66 | if (((ucontext_t*)cothread)->uc_stack.ss_sp) | |
| 67 | free(((ucontext_t*)cothread)->uc_stack.ss_sp); | |
| 68 | free(cothread); | |
| 69 | } | |
| 70 | ||
| 71 | void co_switch(cothread_t cothread) | |
| 72 | { | |
| 73 | ucontext_t *old_thread = co_running; | |
| 74 | co_running = (ucontext_t*)cothread; | |
| 75 | swapcontext(old_thread, co_running); | |
| 76 | } | |
| 77 | ||
| 78 | #ifdef __cplusplus | |
| 79 | } | |
| 80 | #endif |