Async-Interrupt/Interrupt.xs

#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"

#include "schmorp.h"

typedef volatile sig_atomic_t atomic_t;

static int *sig_pending, *psig_pend; /* make local copies because of missing THX */
static Sighandler_t old_sighandler;
static atomic_t async_pending;

#define PERL_VERSION_ATLEAST(a,b,c)                             \
  (PERL_REVISION > (a)                                          \
   || (PERL_REVISION == (a)                                     \
       && (PERL_VERSION > (b)                                   \
           || (PERL_VERSION == (b) && PERL_SUBVERSION >= (c)))))

#if defined(HAS_SIGACTION) && defined(SA_SIGINFO)
# define HAS_SA_SIGINFO 1
#endif

#if !PERL_VERSION_ATLEAST(5,10,0)
# undef HAS_SA_SIGINFO
#endif

/*****************************************************************************/

typedef struct {
  SV *cb;
  void (*c_cb)(pTHX_ void *c_arg, int value);
  void *c_arg;
  SV *fh_r, *fh_w;
  SV *value;
  int signum;
  volatile int blocked;

  s_epipe ep;
  int fd_wlen;
  atomic_t fd_enable;
  atomic_t pending;
  volatile IV *valuep;
} async_t;

static AV *asyncs;
static async_t *sig_async [SIG_SIZE];

#define SvASYNC_nrv(sv) INT2PTR (async_t *, SvIVX (sv))
#define SvASYNC(rv)     SvASYNC_nrv (SvRV (rv))

/* the main workhorse to signal */
static void
async_signal (void *signal_arg, int value)
{
  static char pipedata [8];

  async_t *async = (async_t *)signal_arg;
  int pending = async->pending;

  *async->valuep = value ? value : 1;
  async->pending = 1;
  async_pending  = 1;
  psig_pend [9]  = 1;
  *sig_pending   = 1;

  if (!pending && async->fd_enable && async->ep.len)
    s_epipe_signal (&async->ep);
}

static void
handle_async (async_t *async)
{
  int old_errno = errno;
  int value = *async->valuep;

  *async->valuep = 0;
  async->pending = 0;

  /* drain pipe */
  if (async->fd_enable && async->ep.len)
    s_epipe_drain (&async->ep);

  if (async->c_cb)
    {
      dTHX;
      async->c_cb (aTHX_ async->c_arg, value);
    }

  if (async->cb)
    {
      dSP;

      SV *saveerr = SvOK (ERRSV) ? sv_mortalcopy (ERRSV) : 0;
      SV *savedie = PL_diehook;

      PL_diehook = 0;

      PUSHSTACKi (PERLSI_SIGNAL);

      PUSHMARK (SP);
      XPUSHs (sv_2mortal (newSViv (value)));
      PUTBACK;
      call_sv (async->cb, G_VOID | G_DISCARD | G_EVAL);

      if (SvTRUE (ERRSV))
        {
          SPAGAIN;

          PUSHMARK (SP);
          PUTBACK;
          call_sv (get_sv ("Async::Interrupt::DIED", 1), G_VOID | G_DISCARD | G_EVAL | G_KEEPERR);

          sv_setpvn (ERRSV, "", 0);
        }

      if (saveerr)
        sv_setsv (ERRSV, saveerr);

      {
        SV *oldhook = PL_diehook;
        PL_diehook = savedie;
        SvREFCNT_dec (oldhook);
      }

      POPSTACK;
    }

  errno = old_errno;
}

static void
handle_asyncs (void)
{
  int i;

  async_pending = 0;

  for (i = AvFILLp (asyncs); i >= 0; --i)
    {
      async_t *async = SvASYNC_nrv (AvARRAY (asyncs)[i]);

      if (async->pending && !async->blocked)
        handle_async (async);
    }
}

#if HAS_SA_SIGINFO
static Signal_t async_sighandler (int signum, siginfo_t *si, void *sarg)
{
  if (signum == 9)
    handle_asyncs ();
  else
    old_sighandler (signum, si, sarg);
}
#else
static Signal_t async_sighandler (int signum)
{
  if (signum == 9)
    handle_asyncs ();
  else
    old_sighandler (signum);
}
#endif

static void
async_sigsend (int signum)
{
  async_signal (sig_async [signum], 0);
}

#define block(async) ++(async)->blocked

static void
unblock (async_t *async)
{
  --async->blocked;
  if (async->pending && !async->blocked)
    handle_async (async);
}

static void
scope_block_cb (pTHX_ void *async_sv)
{
  async_t *async = SvASYNC_nrv ((SV *)async_sv);
  unblock (async);
  SvREFCNT_dec (async_sv);
}

MODULE = Async::Interrupt               PACKAGE = Async::Interrupt

BOOT:
        old_sighandler = PL_sighandlerp;
        PL_sighandlerp = async_sighandler;
        sig_pending = &PL_sig_pending;
        psig_pend   = PL_psig_pend;
        asyncs      = newAV ();
        CvNODEBUG_on (get_cv ("Async::Interrupt::scope_block", 0)); /* otherwise calling scope can be the debugger */

PROTOTYPES: DISABLE

void
_alloc (SV *cb, void *c_cb, void *c_arg, SV *fh_r, SV *fh_w, SV *signl, SV *pvalue)
        PPCODE:
{
        SV *cv   = SvOK (cb) ? SvREFCNT_inc (s_get_cv_croak (cb)) : 0;
        async_t *async;

        Newz (0, async, 1, async_t);

        XPUSHs (sv_2mortal (newSViv (PTR2IV (async))));
        /* TODO: need to bless right now to ensure deallocation */
        av_push (asyncs, TOPs);

        SvGETMAGIC (fh_r); SvGETMAGIC (fh_w);
        if (SvOK (fh_r) || SvOK (fh_w))
          {
            int fd_r = s_fileno_croak (fh_r, 0);
            int fd_w = s_fileno_croak (fh_w, 1);

            async->fh_r      = newSVsv (fh_r);
            async->fh_w      = newSVsv (fh_w);
            async->ep.fd [0] = fd_r;
            async->ep.fd [1] = fd_w;
            async->ep.len    = 1;
            async->fd_enable = 1;
          }

        async->value     = SvROK (pvalue)
                           ? SvREFCNT_inc_NN (SvRV (pvalue))
                           : NEWSV (0, 0);

        sv_setiv (async->value, 0);
        SvIOK_only (async->value); /* just to be sure */
        SvREADONLY_on (async->value);

        async->valuep    = &(SvIVX (async->value));

        async->cb        = cv;
        async->c_cb      = c_cb;
        async->c_arg     = c_arg;
        async->signum    = SvOK (signl) ? s_signum_croak (signl) : 0;

        if (async->signum)
          {
            if (async->signum < 0)
              croak ("Async::Interrupt::new got passed illegal signal name or number: %s", SvPV_nolen (signl));

            sig_async [async->signum] = async;
#if _WIN32
            signal (async->signum, async_sigsend);
#else
            {
              struct sigaction sa = { };
              sa.sa_handler = async_sigsend;
              sigfillset (&sa.sa_mask);
              sigaction (async->signum, &sa, 0);
            }
#endif
          }
}

void
signal_func (async_t *async)
        PPCODE:
        EXTEND (SP, 2);
        PUSHs (sv_2mortal (newSViv (PTR2IV (async_signal))));
        PUSHs (sv_2mortal (newSViv (PTR2IV (async))));

IV
c_var (async_t *async)
        CODE:
        RETVAL = PTR2IV (async->valuep);
        OUTPUT:
        RETVAL

void
signal (async_t *async, int value = 1)
        CODE:
        async_signal (async, value);

void
block (async_t *async)
        CODE:
        block (async);

void
unblock (async_t *async)
        CODE:
        unblock (async);

void
scope_block (SV *self)
        CODE:
{
        SV *async_sv = SvRV (self);
        async_t *async = SvASYNC_nrv (async_sv);
        block (async);

        LEAVE; /* unfortunately, perl sandwiches XS calls into ENTER/LEAVE */
        SAVEDESTRUCTOR_X (scope_block_cb, (void *)SvREFCNT_inc (async_sv));
        ENTER; /* unfortunately, perl sandwiches XS calls into ENTER/LEAVE */
}

void
pipe_enable (async_t *async)
        ALIAS:
        pipe_enable = 1
        pipe_disable = 0
        CODE:
        async->fd_enable = ix;

int
pipe_fileno (async_t *async)
        CODE:
        if (!async->ep.len)
          {
            int res;

            /*block (async);*//*TODO*/
            res = s_epipe_new (&async->ep);
            async->fd_enable = 1;
            /*unblock (async);*//*TODO*/

            if (res < 0)
              croak ("Async::Interrupt: unable to initialize event pipe");
          }

        RETVAL = async->ep.fd [0];
        OUTPUT:
        RETVAL


void
post_fork (async_t *async)
        CODE:
        if (async->ep.len)
          {
            int res;

            /*block (async);*//*TODO*/
            res = s_epipe_renew (&async->ep);
            /*unblock (async);*//*TODO*/

            if (res < 0)
              croak ("Async::Interrupt: unable to initialize event pipe after fork");
          }

void
DESTROY (SV *self)
        CODE:
{
        int i;
        SV *async_sv = SvRV (self);
        async_t *async = SvASYNC_nrv (async_sv);

        for (i = AvFILLp (asyncs); i >= 0; --i)
          if (AvARRAY (asyncs)[i] == async_sv)
            {
              if (i < AvFILLp (asyncs))
                AvARRAY (asyncs)[i] = AvARRAY (asyncs)[AvFILLp (asyncs)];

              assert (av_pop (asyncs) == async_sv);
              goto found;
            }

        if (!PL_dirty)
          warn ("Async::Interrupt::DESTROY could not find async object in list of asyncs, please report");

        found:

        if (async->signum)
          {
#if _WIN32
            signal (async->signum, SIG_DFL);
#else
            {
              struct sigaction sa = { };
              sa.sa_handler = SIG_DFL;
              sigaction (async->signum, &sa, 0);
            }
#endif
          }

        if (!async->fh_r && async->ep.len)
          s_epipe_destroy (&async->ep);

        SvREFCNT_dec (async->fh_r);
        SvREFCNT_dec (async->fh_w);
        SvREFCNT_dec (async->cb);
        SvREFCNT_dec (async->value);

        Safefree (async);
}

Revision:	1.10
Committed:	Fri Jul 17 03:32:29 2009 UTC (17 years, 2 months ago) by root
Branch:	MAIN
CVS Tags:	rel-0_501
Changes since 1.9:	+3 -7 lines
Log Message:	* empty log message *
#	Content
1	#include "EXTERN.h"
2	#include "perl.h"
3	#include "XSUB.h"
4
5	#include "schmorp.h"
6
7	typedef volatile sig_atomic_t atomic_t;
8
9	static int sig_pending, psig_pend; /* make local copies because of missing THX */
10	static Sighandler_t old_sighandler;
11	static atomic_t async_pending;
12
13	#define PERL_VERSION_ATLEAST(a,b,c) \
14	(PERL_REVISION > (a) \
15	\|\| (PERL_REVISION == (a) \
16	&& (PERL_VERSION > (b) \
17	\|\| (PERL_VERSION == (b) && PERL_SUBVERSION >= (c)))))
18
19	#if defined(HAS_SIGACTION) && defined(SA_SIGINFO)
20	# define HAS_SA_SIGINFO 1
21	#endif
22
23	#if !PERL_VERSION_ATLEAST(5,10,0)
24	# undef HAS_SA_SIGINFO
25	#endif
26
27	/*****************************************************************************/
28
29	typedef struct {
30	SV *cb;
31	void (c_cb)(pTHX_ void c_arg, int value);
32	void *c_arg;
33	SV fh_r, fh_w;
34	SV *value;
35	int signum;
36	volatile int blocked;
37
38	s_epipe ep;
39	int fd_wlen;
40	atomic_t fd_enable;
41	atomic_t pending;
42	volatile IV *valuep;
43	} async_t;
44
45	static AV *asyncs;
46	static async_t *sig_async [SIG_SIZE];
47
48	#define SvASYNC_nrv(sv) INT2PTR (async_t *, SvIVX (sv))
49	#define SvASYNC(rv) SvASYNC_nrv (SvRV (rv))
50
51	/* the main workhorse to signal */
52	static void
53	async_signal (void *signal_arg, int value)
54	{
55	static char pipedata [8];
56
57	async_t async = (async_t )signal_arg;
58	int pending = async->pending;
59
60	*async->valuep = value ? value : 1;
61	async->pending = 1;
62	async_pending = 1;
63	psig_pend [9] = 1;
64	*sig_pending = 1;
65
66	if (!pending && async->fd_enable && async->ep.len)
67	s_epipe_signal (&async->ep);
68	}
69
70	static void
71	handle_async (async_t *async)
72	{
73	int old_errno = errno;
74	int value = *async->valuep;
75
76	*async->valuep = 0;
77	async->pending = 0;
78
79	/* drain pipe */
80	if (async->fd_enable && async->ep.len)
81	s_epipe_drain (&async->ep);
82
83	if (async->c_cb)
84	{
85	dTHX;
86	async->c_cb (aTHX_ async->c_arg, value);
87	}
88
89	if (async->cb)
90	{
91	dSP;
92
93	SV *saveerr = SvOK (ERRSV) ? sv_mortalcopy (ERRSV) : 0;
94	SV *savedie = PL_diehook;
95
96	PL_diehook = 0;
97
98	PUSHSTACKi (PERLSI_SIGNAL);
99
100	PUSHMARK (SP);
101	XPUSHs (sv_2mortal (newSViv (value)));
102	PUTBACK;
103	call_sv (async->cb, G_VOID \| G_DISCARD \| G_EVAL);
104
105	if (SvTRUE (ERRSV))
106	{
107	SPAGAIN;
108
109	PUSHMARK (SP);
110	PUTBACK;
111	call_sv (get_sv ("Async::Interrupt::DIED", 1), G_VOID \| G_DISCARD \| G_EVAL \| G_KEEPERR);
112
113	sv_setpvn (ERRSV, "", 0);
114	}
115
116	if (saveerr)
117	sv_setsv (ERRSV, saveerr);
118
119	{
120	SV *oldhook = PL_diehook;
121	PL_diehook = savedie;
122	SvREFCNT_dec (oldhook);
123	}
124
125	POPSTACK;
126	}
127
128	errno = old_errno;
129	}
130
131	static void
132	handle_asyncs (void)
133	{
134	int i;
135
136	async_pending = 0;
137
138	for (i = AvFILLp (asyncs); i >= 0; --i)
139	{
140	async_t *async = SvASYNC_nrv (AvARRAY (asyncs)[i]);
141
142	if (async->pending && !async->blocked)
143	handle_async (async);
144	}
145	}
146
147	#if HAS_SA_SIGINFO
148	static Signal_t async_sighandler (int signum, siginfo_t si, void sarg)
149	{
150	if (signum == 9)
151	handle_asyncs ();
152	else
153	old_sighandler (signum, si, sarg);
154	}
155	#else
156	static Signal_t async_sighandler (int signum)
157	{
158	if (signum == 9)
159	handle_asyncs ();
160	else
161	old_sighandler (signum);
162	}
163	#endif
164
165	static void
166	async_sigsend (int signum)
167	{
168	async_signal (sig_async [signum], 0);
169	}
170
171	#define block(async) ++(async)->blocked
172
173	static void
174	unblock (async_t *async)
175	{
176	--async->blocked;
177	if (async->pending && !async->blocked)
178	handle_async (async);
179	}
180
181	static void
182	scope_block_cb (pTHX_ void *async_sv)
183	{
184	async_t async = SvASYNC_nrv ((SV )async_sv);
185	unblock (async);
186	SvREFCNT_dec (async_sv);
187	}
188
189	MODULE = Async::Interrupt PACKAGE = Async::Interrupt
190
191	BOOT:
192	old_sighandler = PL_sighandlerp;
193	PL_sighandlerp = async_sighandler;
194	sig_pending = &PL_sig_pending;
195	psig_pend = PL_psig_pend;
196	asyncs = newAV ();
197	CvNODEBUG_on (get_cv ("Async::Interrupt::scope_block", 0)); /* otherwise calling scope can be the debugger */
198
199	PROTOTYPES: DISABLE
200
201	void
202	_alloc (SV cb, void c_cb, void c_arg, SV fh_r, SV fh_w, SV signl, SV *pvalue)
203	PPCODE:
204	{
205	SV *cv = SvOK (cb) ? SvREFCNT_inc (s_get_cv_croak (cb)) : 0;
206	async_t *async;
207
208	Newz (0, async, 1, async_t);
209
210	XPUSHs (sv_2mortal (newSViv (PTR2IV (async))));
211	/* TODO: need to bless right now to ensure deallocation */
212	av_push (asyncs, TOPs);
213
214	SvGETMAGIC (fh_r); SvGETMAGIC (fh_w);
215	if (SvOK (fh_r) \|\| SvOK (fh_w))
216	{
217	int fd_r = s_fileno_croak (fh_r, 0);
218	int fd_w = s_fileno_croak (fh_w, 1);
219
220	async->fh_r = newSVsv (fh_r);
221	async->fh_w = newSVsv (fh_w);
222	async->ep.fd [0] = fd_r;
223	async->ep.fd [1] = fd_w;
224	async->ep.len = 1;
225	async->fd_enable = 1;
226	}
227
228	async->value = SvROK (pvalue)
229	? SvREFCNT_inc_NN (SvRV (pvalue))
230	: NEWSV (0, 0);
231
232	sv_setiv (async->value, 0);
233	SvIOK_only (async->value); /* just to be sure */
234	SvREADONLY_on (async->value);
235
236	async->valuep = &(SvIVX (async->value));
237
238	async->cb = cv;
239	async->c_cb = c_cb;
240	async->c_arg = c_arg;
241	async->signum = SvOK (signl) ? s_signum_croak (signl) : 0;
242
243	if (async->signum)
244	{
245	if (async->signum < 0)
246	croak ("Async::Interrupt::new got passed illegal signal name or number: %s", SvPV_nolen (signl));
247
248	sig_async [async->signum] = async;
249	#if _WIN32
250	signal (async->signum, async_sigsend);
251	#else
252	{
253	struct sigaction sa = { };
254	sa.sa_handler = async_sigsend;
255	sigfillset (&sa.sa_mask);
256	sigaction (async->signum, &sa, 0);
257	}
258	#endif
259	}
260	}
261
262	void
263	signal_func (async_t *async)
264	PPCODE:
265	EXTEND (SP, 2);
266	PUSHs (sv_2mortal (newSViv (PTR2IV (async_signal))));
267	PUSHs (sv_2mortal (newSViv (PTR2IV (async))));
268
269	IV
270	c_var (async_t *async)
271	CODE:
272	RETVAL = PTR2IV (async->valuep);
273	OUTPUT:
274	RETVAL
275
276	void
277	signal (async_t *async, int value = 1)
278	CODE:
279	async_signal (async, value);
280
281	void
282	block (async_t *async)
283	CODE:
284	block (async);
285
286	void
287	unblock (async_t *async)
288	CODE:
289	unblock (async);
290
291	void
292	scope_block (SV *self)
293	CODE:
294	{
295	SV *async_sv = SvRV (self);
296	async_t *async = SvASYNC_nrv (async_sv);
297	block (async);
298
299	LEAVE; /* unfortunately, perl sandwiches XS calls into ENTER/LEAVE */
300	SAVEDESTRUCTOR_X (scope_block_cb, (void *)SvREFCNT_inc (async_sv));
301	ENTER; /* unfortunately, perl sandwiches XS calls into ENTER/LEAVE */
302	}
303
304	void
305	pipe_enable (async_t *async)
306	ALIAS:
307	pipe_enable = 1
308	pipe_disable = 0
309	CODE:
310	async->fd_enable = ix;
311
312	int
313	pipe_fileno (async_t *async)
314	CODE:
315	if (!async->ep.len)
316	{
317	int res;
318
319	/block (async);//TODO/
320	res = s_epipe_new (&async->ep);
321	async->fd_enable = 1;
322	/unblock (async);//TODO/
323
324	if (res < 0)
325	croak ("Async::Interrupt: unable to initialize event pipe");
326	}
327
328	RETVAL = async->ep.fd [0];
329	OUTPUT:
330	RETVAL
331
332
333	void
334	post_fork (async_t *async)
335	CODE:
336	if (async->ep.len)
337	{
338	int res;
339
340	/block (async);//TODO/
341	res = s_epipe_renew (&async->ep);
342	/unblock (async);//TODO/
343
344	if (res < 0)
345	croak ("Async::Interrupt: unable to initialize event pipe after fork");
346	}
347
348	void
349	DESTROY (SV *self)
350	CODE:
351	{
352	int i;
353	SV *async_sv = SvRV (self);
354	async_t *async = SvASYNC_nrv (async_sv);
355
356	for (i = AvFILLp (asyncs); i >= 0; --i)
357	if (AvARRAY (asyncs)[i] == async_sv)
358	{
359	if (i < AvFILLp (asyncs))
360	AvARRAY (asyncs)[i] = AvARRAY (asyncs)[AvFILLp (asyncs)];
361
362	assert (av_pop (asyncs) == async_sv);
363	goto found;
364	}
365
366	if (!PL_dirty)
367	warn ("Async::Interrupt::DESTROY could not find async object in list of asyncs, please report");
368
369	found:
370
371	if (async->signum)
372	{
373	#if _WIN32
374	signal (async->signum, SIG_DFL);
375	#else
376	{
377	struct sigaction sa = { };
378	sa.sa_handler = SIG_DFL;
379	sigaction (async->signum, &sa, 0);
380	}
381	#endif
382	}
383
384	if (!async->fh_r && async->ep.len)
385	s_epipe_destroy (&async->ep);
386
387	SvREFCNT_dec (async->fh_r);
388	SvREFCNT_dec (async->fh_w);
389	SvREFCNT_dec (async->cb);
390	SvREFCNT_dec (async->value);
391
392	Safefree (async);
393	}
394