/*
* Empire - A multi-player, client/server Internet based war game.
- * Copyright (C) 1986-2009, Dave Pare, Jeff Bailey, Thomas Ruschak,
- * Ken Stevens, Steve McClure
+ * Copyright (C) 1986-2011, Dave Pare, Jeff Bailey, Thomas Ruschak,
+ * Ken Stevens, Steve McClure, Markus Armbruster
*
- * This program is free software; you can redistribute it and/or modify
+ * Empire is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
+ * the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
- * along with this program; if not, write to the Free Software
- * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
*
* ---
*
#include <unistd.h>
#include "empio.h"
#include "empthread.h"
+#include "file.h"
#include "ioqueue.h"
#include "misc.h"
#include "queue.h"
-#include "server.h"
struct iop {
int fd;
struct ioqueue *output;
int flags;
int bufsize;
+ int last_out;
struct timeval input_timeout;
};
iop->input = NULL;
iop->output = NULL;
iop->flags = flags;
+ iop->last_out = 0;
iop->bufsize = bufsize;
iop->input_timeout = timeout;
if (flags & IO_READ)
return ioq_qsize(iop->output);
}
+/*
+ * Write output queued in IOP.
+ * If WAIT, writing may put the thread to sleep.
+ * Return number of bytes written on success, -1 on error.
+ * In particular, return zero when nothing was written because the
+ * queue was empty, or because the write slept and got woken up (only
+ * if WAIT), or because the write refused to sleep (only if !WAIT).
+ */
int
-io_output(struct iop *iop, int waitforoutput)
+io_output(struct iop *iop, int wait)
{
struct iovec iov[16];
- int cc;
- int n;
- int remain;
+ int n, res, cc;
- /* If there is no output waiting. */
- if (!io_outputwaiting(iop))
+ if (wait)
+ ef_make_stale();
+
+ if (!ioq_qsize(iop->output))
return 0;
- /* If the iop is not write enabled. */
if ((iop->flags & IO_WRITE) == 0)
return -1;
- /* If the io is marked as in error... */
if (iop->flags & IO_ERROR)
return -1;
- /* make the iov point to the data in the queue. */
- /* I.E., each of the elements in the queue. */
- /* returns the number of elements in the iov. */
- n = ioq_makeiov(iop->output, iov, IO_BUFSIZE);
-
- if (n <= 0) {
- return 0;
- }
-
- /* wait for the file to be output ready. */
- if (waitforoutput != IO_NOWAIT) {
- /* This waits for the file to be ready for writing, */
- /* and lets other threads run. */
- empth_select(iop->fd, EMPTH_FD_WRITE, NULL);
+ if (wait) {
+ res = empth_select(iop->fd, EMPTH_FD_WRITE, NULL);
+ if (res == 0)
+ return 0;
+ if (res < 0) {
+ iop->flags |= IO_ERROR;
+ return -1;
+ }
}
- /* Do the actual write. */
+ n = ioq_makeiov(iop->output, iov, IO_BUFSIZE);
cc = writev(iop->fd, iov, n);
-
- /* if it failed.... */
if (cc < 0) {
- /* Hmm, it would block. file is opened noblock, soooooo.. */
- if (errno == EAGAIN || errno == EWOULDBLOCK) {
- /* If there are remaining bytes, set the IO as remaining.. */
- remain = ioq_qsize(iop->output);
- return remain;
- }
+ if (errno == EAGAIN || errno == EWOULDBLOCK)
+ return 0;
iop->flags |= IO_ERROR;
return -1;
}
- /* If no bytes were written, something happened.. Like an EOF. */
- if (cc == 0) {
- iop->flags |= IO_EOF;
- return 0;
- }
-
- /* Remove the number of written bytes from the queue. */
ioq_dequeue(iop->output, cc);
-
+ iop->last_out = ioq_qsize(iop->output);
return cc;
}
+/*
+ * Write output queued in IOP if enough have been enqueued.
+ * Write if at least one buffer has been filled since the last write.
+ * If WAIT, writing may put the thread to sleep.
+ * Return number of bytes written on success, -1 on error.
+ * In particular, return zero when nothing was written because the
+ * queue was not long, or the write slept and got woken up (only if
+ * WAIT), or the write refused to sleep (only if !WAIT).
+ */
+int
+io_output_if_queue_long(struct iop *iop, int wait)
+{
+ int len = ioq_qsize(iop->output);
+
+ if (CANT_HAPPEN(iop->last_out > len))
+ iop->last_out = 0;
+ if (len - iop->last_out < iop->bufsize) {
+ if (wait)
+ ef_make_stale();
+ return 0;
+ }
+ return io_output(iop, wait);
+}
+
+
int
io_peek(struct iop *iop, char *buf, int nbytes)
{
}
int
-io_write(struct iop *iop, char *buf, int nbytes, int doWait)
+io_write(struct iop *iop, char *buf, int nbytes)
{
- int len;
-
if ((iop->flags & IO_WRITE) == 0)
return -1;
ioq_append(iop->output, buf, nbytes);
- len = ioq_qsize(iop->output);
- if (len > iop->bufsize) {
- if (doWait) {
- io_output_all(iop);
- } else {
- /* only try a write every BUFSIZE characters */
- if (((len - nbytes) % iop->bufsize) < (len % iop->bufsize))
- io_output(iop, IO_NOWAIT);
- }
- }
return nbytes;
}
-int
-io_output_all(struct iop *iop)
-{
- int n;
-
- /*
- * Mustn't block a player thread while update is pending, or else
- * a malicous player could delay the update indefinitely
- */
- while ((n = io_output(iop, IO_NOWAIT)) > 0 && !play_wrlock_wanted)
- empth_select(iop->fd, EMPTH_FD_WRITE, NULL);
-
- return n;
-}
-
int
io_gets(struct iop *iop, char *buf, int nbytes)
{
if (flags & IO_WRITE) {
shutdown(iop->fd, 1);
ioq_drain(iop->output);
+ iop->last_out = 0;
}
return 0;
}
projects / empserver / blobdiff