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/*
*
* clientloop.c
*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
*
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
*
*
* Created: Sat Sep 23 12:23:57 1995 ylo
*
* The main loop for the interactive session (client side).
*
*/
#include "includes.h"
RCSID("$Id: clientloop.c,v 1.5 1999/11/24 13:26:22 damien Exp $");
#include "xmalloc.h"
#include "ssh.h"
#include "packet.h"
#include "buffer.h"
#include "authfd.h"
#include "readconf.h"
/* Flag indicating that stdin should be redirected from /dev/null. */
extern int stdin_null_flag;
/* Name of the host we are connecting to. This is the name given on the
command line, or the HostName specified for the user-supplied name
in a configuration file. */
extern char *host;
/* Flag to indicate that we have received a window change signal which has
not yet been processed. This will cause a message indicating the new
window size to be sent to the server a little later. This is volatile
because this is updated in a signal handler. */
static volatile int received_window_change_signal = 0;
/* Terminal modes, as saved by enter_raw_mode. */
static struct termios saved_tio;
/* Flag indicating whether we are in raw mode. This is used by enter_raw_mode
and leave_raw_mode. */
static int in_raw_mode = 0;
/* Flag indicating whether the user\'s terminal is in non-blocking mode. */
static int in_non_blocking_mode = 0;
/* Common data for the client loop code. */
static int escape_pending; /* Last character was the escape character */
static int last_was_cr; /* Last character was a newline. */
static int exit_status; /* Used to store the exit status of the command. */
static int stdin_eof; /* EOF has been encountered on standard error. */
static Buffer stdin_buffer; /* Buffer for stdin data. */
static Buffer stdout_buffer; /* Buffer for stdout data. */
static Buffer stderr_buffer; /* Buffer for stderr data. */
static unsigned int buffer_high;/* Soft max buffer size. */
static int max_fd; /* Maximum file descriptor number in select(). */
static int connection_in; /* Connection to server (input). */
static int connection_out; /* Connection to server (output). */
static unsigned long stdin_bytes, stdout_bytes, stderr_bytes;
static int quit_pending; /* Set to non-zero to quit the client loop. */
static int escape_char; /* Escape character. */
/* Returns the user\'s terminal to normal mode if it had been put in raw
mode. */
void
leave_raw_mode()
{
if (!in_raw_mode)
return;
in_raw_mode = 0;
if (tcsetattr(fileno(stdin), TCSADRAIN, &saved_tio) < 0)
perror("tcsetattr");
fatal_remove_cleanup((void (*) (void *)) leave_raw_mode, NULL);
}
/* Puts the user\'s terminal in raw mode. */
void
enter_raw_mode()
{
struct termios tio;
if (tcgetattr(fileno(stdin), &tio) < 0)
perror("tcgetattr");
saved_tio = tio;
tio.c_iflag |= IGNPAR;
tio.c_iflag &= ~(ISTRIP | INLCR | IGNCR | ICRNL | IXON | IXANY | IXOFF);
tio.c_lflag &= ~(ISIG | ICANON | ECHO | ECHOE | ECHOK | ECHONL);
#ifdef IEXTEN
tio.c_lflag &= ~IEXTEN;
#endif /* IEXTEN */
tio.c_oflag &= ~OPOST;
tio.c_cc[VMIN] = 1;
tio.c_cc[VTIME] = 0;
if (tcsetattr(fileno(stdin), TCSADRAIN, &tio) < 0)
perror("tcsetattr");
in_raw_mode = 1;
fatal_add_cleanup((void (*) (void *)) leave_raw_mode, NULL);
}
/* Restores stdin to blocking mode. */
void
leave_non_blocking()
{
if (in_non_blocking_mode) {
(void) fcntl(fileno(stdin), F_SETFL, 0);
in_non_blocking_mode = 0;
fatal_remove_cleanup((void (*) (void *)) leave_non_blocking, NULL);
}
}
/* Puts stdin terminal in non-blocking mode. */
void
enter_non_blocking()
{
in_non_blocking_mode = 1;
(void) fcntl(fileno(stdin), F_SETFL, O_NONBLOCK);
fatal_add_cleanup((void (*) (void *)) leave_non_blocking, NULL);
}
/* Signal handler for the window change signal (SIGWINCH). This just
sets a flag indicating that the window has changed. */
void
window_change_handler(int sig)
{
received_window_change_signal = 1;
signal(SIGWINCH, window_change_handler);
}
/* Signal handler for signals that cause the program to terminate. These
signals must be trapped to restore terminal modes. */
void
signal_handler(int sig)
{
if (in_raw_mode)
leave_raw_mode();
if (in_non_blocking_mode)
leave_non_blocking();
channel_stop_listening();
packet_close();
fatal("Killed by signal %d.", sig);
}
/* Returns current time in seconds from Jan 1, 1970 with the maximum available
resolution. */
double
get_current_time()
{
struct timeval tv;
gettimeofday(&tv, NULL);
return (double) tv.tv_sec + (double) tv.tv_usec / 1000000.0;
}
/* This is called when the interactive is entered. This checks if there
is an EOF coming on stdin. We must check this explicitly, as select()
does not appear to wake up when redirecting from /dev/null. */
void
client_check_initial_eof_on_stdin()
{
int len;
char buf[1];
/* If standard input is to be "redirected from /dev/null", we
simply mark that we have seen an EOF and send an EOF message to
the server. Otherwise, we try to read a single character; it
appears that for some files, such /dev/null, select() never
wakes up for read for this descriptor, which means that we
never get EOF. This way we will get the EOF if stdin comes
from /dev/null or similar. */
if (stdin_null_flag) {
/* Fake EOF on stdin. */
debug("Sending eof.");
stdin_eof = 1;
packet_start(
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