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kc3-lang/libevent/win32select.c

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  • Author : Azat Khuzhin
    Date : 2019-01-29 07:56:21
    Hash : 8882f4fd
    Message : win32select: print an error in case of failure

  • win32select.c
  • /*
     * Copyright 2007-2012 Niels Provos and Nick Mathewson
     * Copyright 2000-2007 Niels Provos <provos@citi.umich.edu>
     * Copyright 2003 Michael A. Davis <mike@datanerds.net>
     *
     * Redistribution and use in source and binary forms, with or without
     * modification, are permitted provided that the following conditions
     * are met:
     * 1. Redistributions of source code must retain the above copyright
     *    notice, this list of conditions and the following disclaimer.
     * 2. Redistributions in binary form must reproduce the above copyright
     *    notice, this list of conditions and the following disclaimer in the
     *    documentation and/or other materials provided with the distribution.
     * 3. The name of the author may not be used to endorse or promote products
     *    derived from this software without specific prior written permission.
     *
     * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
     * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
     * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
     * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
     * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
     * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
     * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
     * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
     * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
     * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
     */
    #include "event2/event-config.h"
    #include "evconfig-private.h"
    
    #ifdef _WIN32
    
    #include <winsock2.h>
    #include <windows.h>
    #include <sys/types.h>
    #include <sys/queue.h>
    #include <limits.h>
    #include <signal.h>
    #include <stdio.h>
    #include <stdlib.h>
    #include <string.h>
    #include <errno.h>
    
    #include "event2/util.h"
    #include "util-internal.h"
    #include "log-internal.h"
    #include "event2/event.h"
    #include "event-internal.h"
    #include "evmap-internal.h"
    #include "event2/thread.h"
    #include "evthread-internal.h"
    #include "time-internal.h"
    
    #define XFREE(ptr) do { if (ptr) mm_free(ptr); } while (0)
    
    extern struct event_list timequeue;
    extern struct event_list addqueue;
    
    struct win_fd_set {
    	unsigned int fd_count;
    	SOCKET fd_array[1];
    };
    
    /* MSDN says this is required to handle SIGFPE */
    volatile double SIGFPE_REQ = 0.0f;
    
    struct idx_info {
    	int read_pos_plus1;
    	int write_pos_plus1;
    };
    
    struct win32op {
    	unsigned num_fds_in_fd_sets;
    	int resize_out_sets;
    	struct win_fd_set *readset_in;
    	struct win_fd_set *writeset_in;
    	struct win_fd_set *readset_out;
    	struct win_fd_set *writeset_out;
    	struct win_fd_set *exset_out;
    	unsigned signals_are_broken : 1;
    };
    
    static void *win32_init(struct event_base *);
    static int win32_add(struct event_base *, evutil_socket_t, short old, short events, void *idx_);
    static int win32_del(struct event_base *, evutil_socket_t, short old, short events, void *idx_);
    static int win32_dispatch(struct event_base *base, struct timeval *);
    static void win32_dealloc(struct event_base *);
    
    struct eventop win32ops = {
    	"win32",
    	win32_init,
    	win32_add,
    	win32_del,
    	win32_dispatch,
    	win32_dealloc,
    	0, /* doesn't need reinit */
    	0, /* No features supported. */
    	sizeof(struct idx_info),
    };
    
    #define FD_SET_ALLOC_SIZE(n) ((sizeof(struct win_fd_set) + ((n)-1)*sizeof(SOCKET)))
    
    static int
    grow_fd_sets(struct win32op *op, unsigned new_num_fds)
    {
    	size_t size;
    
    	EVUTIL_ASSERT(new_num_fds >= op->readset_in->fd_count &&
    	       new_num_fds >= op->writeset_in->fd_count);
    	EVUTIL_ASSERT(new_num_fds >= 1);
    
    	size = FD_SET_ALLOC_SIZE(new_num_fds);
    	if (!(op->readset_in = mm_realloc(op->readset_in, size)))
    		return (-1);
    	if (!(op->writeset_in = mm_realloc(op->writeset_in, size)))
    		return (-1);
    	op->resize_out_sets = 1;
    	op->num_fds_in_fd_sets = new_num_fds;
    	return (0);
    }
    
    static int
    do_fd_set(struct win32op *op, struct idx_info *ent, evutil_socket_t s, int read)
    {
    	struct win_fd_set *set = read ? op->readset_in : op->writeset_in;
    	if (read) {
    		if (ent->read_pos_plus1 > 0)
    			return (0);
    	} else {
    		if (ent->write_pos_plus1 > 0)
    			return (0);
    	}
    	if (set->fd_count == op->num_fds_in_fd_sets) {
    		if (grow_fd_sets(op, op->num_fds_in_fd_sets*2))
    			return (-1);
    		/* set pointer will have changed and needs reiniting! */
    		set = read ? op->readset_in : op->writeset_in;
    	}
    	set->fd_array[set->fd_count] = s;
    	if (read)
    		ent->read_pos_plus1 = set->fd_count+1;
    	else
    		ent->write_pos_plus1 = set->fd_count+1;
    	return (set->fd_count++);
    }
    
    static int
    do_fd_clear(struct event_base *base,
    			struct win32op *op, struct idx_info *ent, int read)
    {
    	int i;
    	struct win_fd_set *set = read ? op->readset_in : op->writeset_in;
    	if (read) {
    		i = ent->read_pos_plus1 - 1;
    		ent->read_pos_plus1 = 0;
    	} else {
    		i = ent->write_pos_plus1 - 1;
    		ent->write_pos_plus1 = 0;
    	}
    	if (i < 0)
    		return (0);
    	if (--set->fd_count != (unsigned)i) {
    		struct idx_info *ent2;
    		SOCKET s2;
    		s2 = set->fd_array[i] = set->fd_array[set->fd_count];
    
    		ent2 = evmap_io_get_fdinfo_(&base->io, s2);
    
    		if (!ent2) /* This indicates a bug. */
    			return (0);
    		if (read)
    			ent2->read_pos_plus1 = i+1;
    		else
    			ent2->write_pos_plus1 = i+1;
    	}
    	return (0);
    }
    
    #define NEVENT 32
    void *
    win32_init(struct event_base *base)
    {
    	struct win32op *winop;
    	size_t size;
    	if (!(winop = mm_calloc(1, sizeof(struct win32op))))
    		return NULL;
    	winop->num_fds_in_fd_sets = NEVENT;
    	size = FD_SET_ALLOC_SIZE(NEVENT);
    	if (!(winop->readset_in = mm_malloc(size)))
    		goto err;
    	if (!(winop->writeset_in = mm_malloc(size)))
    		goto err;
    	if (!(winop->readset_out = mm_malloc(size)))
    		goto err;
    	if (!(winop->writeset_out = mm_malloc(size)))
    		goto err;
    	if (!(winop->exset_out = mm_malloc(size)))
    		goto err;
    	winop->readset_in->fd_count = winop->writeset_in->fd_count = 0;
    	winop->readset_out->fd_count = winop->writeset_out->fd_count
    		= winop->exset_out->fd_count = 0;
    
    	if (evsig_init_(base) < 0)
    		winop->signals_are_broken = 1;
    
    	evutil_weakrand_seed_(&base->weakrand_seed, 0);
    
    	return (winop);
     err:
    	XFREE(winop->readset_in);
    	XFREE(winop->writeset_in);
    	XFREE(winop->readset_out);
    	XFREE(winop->writeset_out);
    	XFREE(winop->exset_out);
    	XFREE(winop);
    	return (NULL);
    }
    
    int
    win32_add(struct event_base *base, evutil_socket_t fd,
    			 short old, short events, void *idx_)
    {
    	struct win32op *win32op = base->evbase;
    	struct idx_info *idx = idx_;
    
    	if ((events & EV_SIGNAL) && win32op->signals_are_broken)
    		return (-1);
    
    	if (!(events & (EV_READ|EV_WRITE)))
    		return (0);
    
    	event_debug(("%s: adding event for %d", __func__, (int)fd));
    	if (events & EV_READ) {
    		if (do_fd_set(win32op, idx, fd, 1)<0)
    			return (-1);
    	}
    	if (events & EV_WRITE) {
    		if (do_fd_set(win32op, idx, fd, 0)<0)
    			return (-1);
    	}
    	return (0);
    }
    
    int
    win32_del(struct event_base *base, evutil_socket_t fd, short old, short events,
    		  void *idx_)
    {
    	struct win32op *win32op = base->evbase;
    	struct idx_info *idx = idx_;
    
    	event_debug(("%s: Removing event for "EV_SOCK_FMT,
    		__func__, EV_SOCK_ARG(fd)));
    	if (events & EV_READ)
    		do_fd_clear(base, win32op, idx, 1);
    	if (events & EV_WRITE)
    		do_fd_clear(base, win32op, idx, 0);
    
    	return 0;
    }
    
    static void
    fd_set_copy(struct win_fd_set *out, const struct win_fd_set *in)
    {
    	out->fd_count = in->fd_count;
    	memcpy(out->fd_array, in->fd_array, in->fd_count * (sizeof(SOCKET)));
    }
    
    /*
      static void dump_fd_set(struct win_fd_set *s)
      {
      unsigned int i;
      printf("[ ");
      for(i=0;i<s->fd_count;++i)
      printf("%d ",(int)s->fd_array[i]);
      printf("]\n");
      }
    */
    
    int
    win32_dispatch(struct event_base *base, struct timeval *tv)
    {
    	struct win32op *win32op = base->evbase;
    	int res = 0;
    	unsigned j, i;
    	int fd_count;
    	SOCKET s;
    
    	if (win32op->resize_out_sets) {
    		size_t size = FD_SET_ALLOC_SIZE(win32op->num_fds_in_fd_sets);
    		if (!(win32op->readset_out = mm_realloc(win32op->readset_out, size)))
    			return (-1);
    		if (!(win32op->exset_out = mm_realloc(win32op->exset_out, size)))
    			return (-1);
    		if (!(win32op->writeset_out = mm_realloc(win32op->writeset_out, size)))
    			return (-1);
    		win32op->resize_out_sets = 0;
    	}
    
    	fd_set_copy(win32op->readset_out, win32op->readset_in);
    	fd_set_copy(win32op->exset_out, win32op->writeset_in);
    	fd_set_copy(win32op->writeset_out, win32op->writeset_in);
    
    	fd_count =
    	    (win32op->readset_out->fd_count > win32op->writeset_out->fd_count) ?
    	    win32op->readset_out->fd_count : win32op->writeset_out->fd_count;
    
    	if (!fd_count) {
    		long msec = tv ? evutil_tv_to_msec_(tv) : LONG_MAX;
    		/* Sleep's DWORD argument is unsigned long */
    		if (msec < 0)
    			msec = LONG_MAX;
    		/* Windows doesn't like you to call select() with no sockets */
    		Sleep(msec);
    		return (0);
    	}
    
    	EVBASE_RELEASE_LOCK(base, th_base_lock);
    
    	res = select(fd_count,
    		     (struct fd_set*)win32op->readset_out,
    		     (struct fd_set*)win32op->writeset_out,
    		     (struct fd_set*)win32op->exset_out, tv);
    
    	EVBASE_ACQUIRE_LOCK(base, th_base_lock);
    
    	event_debug(("%s: select returned %d", __func__, res));
    
    	if (res <= 0) {
    		event_debug(("%s: %s", __func__,
    		    evutil_socket_error_to_string(EVUTIL_SOCKET_ERROR())));
    		return res;
    	}
    
    	if (win32op->readset_out->fd_count) {
    		i = evutil_weakrand_range_(&base->weakrand_seed,
    		    win32op->readset_out->fd_count);
    		for (j=0; j<win32op->readset_out->fd_count; ++j) {
    			if (++i >= win32op->readset_out->fd_count)
    				i = 0;
    			s = win32op->readset_out->fd_array[i];
    			evmap_io_active_(base, s, EV_READ);
    		}
    	}
    	if (win32op->exset_out->fd_count) {
    		i = evutil_weakrand_range_(&base->weakrand_seed,
    		    win32op->exset_out->fd_count);
    		for (j=0; j<win32op->exset_out->fd_count; ++j) {
    			if (++i >= win32op->exset_out->fd_count)
    				i = 0;
    			s = win32op->exset_out->fd_array[i];
    			evmap_io_active_(base, s, EV_WRITE);
    		}
    	}
    	if (win32op->writeset_out->fd_count) {
    		SOCKET s;
    		i = evutil_weakrand_range_(&base->weakrand_seed,
    		    win32op->writeset_out->fd_count);
    		for (j=0; j<win32op->writeset_out->fd_count; ++j) {
    			if (++i >= win32op->writeset_out->fd_count)
    				i = 0;
    			s = win32op->writeset_out->fd_array[i];
    			evmap_io_active_(base, s, EV_WRITE);
    		}
    	}
    	return (0);
    }
    
    void
    win32_dealloc(struct event_base *base)
    {
    	struct win32op *win32op = base->evbase;
    
    	evsig_dealloc_(base);
    	if (win32op->readset_in)
    		mm_free(win32op->readset_in);
    	if (win32op->writeset_in)
    		mm_free(win32op->writeset_in);
    	if (win32op->readset_out)
    		mm_free(win32op->readset_out);
    	if (win32op->writeset_out)
    		mm_free(win32op->writeset_out);
    	if (win32op->exset_out)
    		mm_free(win32op->exset_out);
    	/* XXXXX free the tree. */
    
    	memset(win32op, 0, sizeof(*win32op));
    	mm_free(win32op);
    }
    
    #endif