The Tor Browser: ipc/chromium/src/third_party/libevent/win32select.c@6474c204b198 (annotated)

ipc/chromium/src/third_party/libevent/win32select.c@6474c204b198 (annotated)

ipc/chromium/src/third_party/libevent/win32select.c

Wed, 31 Dec 2014 06:09:35 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Wed, 31 Dec 2014 06:09:35 +0100
changeset 0: 6474c204b198
permissions: -rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

 /*
  * 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 <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 "event2/event-config.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"
 #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 {
 	u_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,
 , /* doesn't need reinit */
 , /* 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;
 	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) {
 		return res;
 	}
 	if (win32op->readset_out->fd_count) {
 		i = rand() % 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 = rand() % 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 = rand() % 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);
 }

The Tor Browser / annotate

ipc/chromium/src/third_party/libevent/win32select.c@6474c204b198 (annotated)

ipc/chromium/src/third_party/libevent/win32select.c