/*
* Empire - A multi-player, client/server Internet based war game.
- * Copyright (C) 1986-2011, Dave Pare, Jeff Bailey, Thomas Ruschak,
+ * Copyright (C) 1986-2017, Dave Pare, Jeff Bailey, Thomas Ruschak,
* Ken Stevens, Steve McClure, Markus Armbruster
*
* Empire is free software: you can redistribute it and/or modify
#include "file.h"
#include "ioqueue.h"
#include "misc.h"
-#include "queue.h"
struct iop {
int fd;
int last_out;
};
+static struct timeval *io_timeout(struct timeval *, time_t);
+
void
io_init(void)
{
return iop;
}
+/*
+ * Close @iop.
+ * Flush output and wait for the client to close the connection.
+ * Wait at most until @deadline. (time_t)-1 means wait as long as it
+ * takes (no timeout).
+ * Both the flush and the wait can be separately cut short by
+ * empth_wakeup(). This is almost certainly not what you want. If
+ * you need early wakeup, better fix this function not to go to sleep
+ * after wakeup during flush.
+ */
void
-io_close(struct iop *iop, struct timeval *timeout)
+io_close(struct iop *iop, time_t deadline)
{
+ struct timeval timeout;
char buf[IO_BUFSIZE];
int ret;
- while (io_output(iop, 1) > 0) ;
+ while (io_output(iop, deadline) > 0) ;
shutdown(iop->fd, SHUT_WR);
- while (empth_select(iop->fd, EMPTH_FD_READ, timeout) > 0) {
+ while (empth_select(iop->fd, EMPTH_FD_READ,
+ io_timeout(&timeout, deadline)) > 0) {
ret = read(iop->fd, buf, sizeof(buf));
if (ret <= 0)
break;
free(iop);
}
+static struct timeval *
+io_timeout(struct timeval *timeout, time_t deadline)
+{
+ struct timeval now;
+
+ if (deadline == (time_t)-1)
+ return NULL; /* no deadline */
+
+ gettimeofday(&now, NULL);
+ if (now.tv_sec >= deadline) {
+ /* deadline reached already */
+ timeout->tv_sec = 0;
+ timeout->tv_usec = 0;
+ } else {
+ /* deadline in future */
+ timeout->tv_sec = deadline - now.tv_sec - 1;
+ timeout->tv_usec = 999999 - now.tv_usec;
+ /* yes, this is 1usec early; sue me */
+ }
+
+ return timeout;
+}
+
/*
- * Read input from IOP and enqueue it.
- * If TIMEOUT is non-null, wait at most that long for input to arrive.
- * Does not yield the processor when timeout is zero.
+ * Read input from @iop and enqueue it.
+ * Wait at most until @deadline for input to arrive. (time_t)-1 means
+ * wait as long as it takes (no timeout).
+ * Does not yield the processor when @deadline is zero.
* A wait for input can be cut short by empth_wakeup().
* Return number of bytes read on success, -1 on error.
* In particular, return zero on timeout, early wakeup or EOF. Use
* io_eof() to distinguish timeout and early wakeup from EOF.
*/
int
-io_input(struct iop *iop, struct timeval *timeout)
+io_input(struct iop *iop, time_t deadline)
{
+ struct timeval timeout;
char buf[IO_BUFSIZE];
int cc;
int res;
if (iop->flags & IO_EOF)
return 0;
- if (!timeout || timeout->tv_sec || timeout->tv_usec) {
- res = empth_select(iop->fd, EMPTH_FD_READ, timeout);
+ if (deadline) {
+ res = empth_select(iop->fd, EMPTH_FD_READ,
+ io_timeout(&timeout, deadline));
if (res < 0) {
iop->flags |= IO_ERROR;
return -1;
}
/*
- * Write output queued in IOP.
- * If WAIT, writing may put the thread to sleep.
+ * Write output queued in @iop.
+ * Wait at most until @deadline for input to arrive. (time_t)-1 means
+ * wait as long as it takes (no timeout).
+ * Does not yield the processor when @deadline is zero.
+ * A wait for output can be cut short by empth_wakeup().
* 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).
+ * queue is empty, and on timeout or early wakeup. Use
+ * io_outputwaiting() to distinguish timeout and early wakeup from
+ * empty queue.
*/
int
-io_output(struct iop *iop, int wait)
+io_output(struct iop *iop, time_t deadline)
{
+ struct timeval timeout;
struct iovec iov[16];
int n, res, cc;
- if (wait)
+ if (deadline)
ef_make_stale();
if ((iop->flags & IO_WRITE) == 0)
if (!ioq_qsize(iop->output))
return 0;
- if (wait) {
- res = empth_select(iop->fd, EMPTH_FD_WRITE, NULL);
+ if (deadline) {
+ res = empth_select(iop->fd, EMPTH_FD_WRITE,
+ io_timeout(&timeout, deadline));
if (res == 0)
return 0;
if (res < 0) {
}
/*
- * Write output queued in IOP if enough have been enqueued.
+ * 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.
+ * Wait at most until @deadline for output to be accepted. (time_t)-1
+ * means wait as long as it takes (no timeout).
+ * Does not yield the processor when @deadline is zero.
+ * A wait for output can be cut short by empth_wakeup().
* 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).
+ * queue isn't long, and on timeout or early wakeup.
*/
int
-io_output_if_queue_long(struct iop *iop, int wait)
+io_output_if_queue_long(struct iop *iop, time_t deadline)
{
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)
+ if (deadline)
ef_make_stale();
return 0;
}
- return io_output(iop, wait);
+ return io_output(iop, deadline);
}
int
return ioq_puts(iop->output, buf);
}
-int
-io_shutdown(struct iop *iop, int flags)
-{
- flags &= (IO_READ | IO_WRITE);
- if ((iop->flags & flags) != flags)
- return -1;
- if (flags & IO_READ) {
- shutdown(iop->fd, 0);
- ioq_drain(iop->input);
- }
- if (flags & IO_WRITE) {
- shutdown(iop->fd, 1);
- ioq_drain(iop->output);
- iop->last_out = 0;
- }
- return 0;
-}
-
int
io_error(struct iop *iop)
{
}
/*
- * Discard IOP's buffered input and set its EOF flag.
- * No more input can be read from IOP.
+ * Discard @iop's buffered input and set its EOF flag.
+ * No more input can be read from @iop.
*/
void
io_set_eof(struct iop *iop)