/*
- * Copyright (C) 2000, 2001 Jeff Dike (jdike@karaya.com)
+ * Copyright (C) 2000 - 2003 Jeff Dike (jdike@addtoit.com)
* Licensed under the GPL
*/
#include <stdlib.h>
#include <errno.h>
#include <termios.h>
-#include <fcntl.h>
#include <string.h>
#include <signal.h>
#include <sys/stat.h>
#include "choose-mode.h"
#include "mode.h"
-void generic_close(int fd, void *unused)
-{
- close(fd);
-}
-
-int generic_read(int fd, char *c_out, void *unused)
-{
- int n;
-
- n = read(fd, c_out, sizeof(*c_out));
- if(n < 0){
- if(errno == EAGAIN) return(0);
- return(-errno);
- }
- else if(n == 0) return(-EIO);
- return(1);
-}
-
-int generic_write(int fd, const char *buf, int n, void *unused)
-{
- int count;
-
- count = write(fd, buf, n);
- if(count < 0) return(-errno);
- return(count);
-}
-
int generic_console_write(int fd, const char *buf, int n, void *unused)
{
struct termios save, new;
int err;
if(isatty(fd)){
- tcgetattr(fd, &save);
+ CATCH_EINTR(err = tcgetattr(fd, &save));
+ if (err)
+ goto error;
new = save;
+ /* The terminal becomes a bit less raw, to handle \n also as
+ * "Carriage Return", not only as "New Line". Otherwise, the new
+ * line won't start at the first column.*/
new.c_oflag |= OPOST;
- tcsetattr(fd, TCSAFLUSH, &new);
+ CATCH_EINTR(err = tcsetattr(fd, TCSAFLUSH, &new));
+ if (err)
+ goto error;
}
err = generic_write(fd, buf, n, NULL);
- if(isatty(fd)) tcsetattr(fd, TCSAFLUSH, &save);
+ /* Restore raw mode, in any case; we *must* ignore any error apart
+ * EINTR, except for debug.*/
+ if(isatty(fd))
+ CATCH_EINTR(tcsetattr(fd, TCSAFLUSH, &save));
return(err);
+error:
+ return(-errno);
}
-int generic_window_size(int fd, void *unused, unsigned short *rows_out,
- unsigned short *cols_out)
-{
- struct winsize size;
- int ret = 0;
-
- if(ioctl(fd, TIOCGWINSZ, &size) == 0){
- ret = ((*rows_out != size.ws_row) ||
- (*cols_out != size.ws_col));
- *rows_out = size.ws_row;
- *cols_out = size.ws_col;
- }
- return(ret);
-}
-
-void generic_free(void *data)
-{
- kfree(data);
-}
+/*
+ * UML SIGWINCH handling
+ *
+ * The point of this is to handle SIGWINCH on consoles which have host ttys and
+ * relay them inside UML to whatever might be running on the console and cares
+ * about the window size (since SIGWINCH notifies about terminal size changes).
+ *
+ * So, we have a separate thread for each host tty attached to a UML device
+ * (side-issue - I'm annoyed that one thread can't have multiple controlling
+ * ttys for purposed of handling SIGWINCH, but I imagine there are other reasons
+ * that doesn't make any sense).
+ *
+ * SIGWINCH can't be received synchronously, so you have to set up to receive it
+ * as a signal. That being the case, if you are going to wait for it, it is
+ * convenient to sit in a pause() and wait for the signal to bounce you out of
+ * it (see below for how we make sure to exit only on SIGWINCH).
+ */
static void winch_handler(int sig)
{
struct winch_data *data = arg;
sigset_t sigs;
int pty_fd, pipe_fd;
+ int count, err;
char c = 1;
- close(data->close_me);
+ os_close_file(data->close_me);
pty_fd = data->pty_fd;
pipe_fd = data->pipe_fd;
- if(write(pipe_fd, &c, sizeof(c)) != sizeof(c))
+ count = os_write_file(pipe_fd, &c, sizeof(c));
+ if(count != sizeof(c))
printk("winch_thread : failed to write synchronization "
- "byte, errno = %d\n", errno);
+ "byte, err = %d\n", -count);
+
+ /* We are not using SIG_IGN on purpose, so don't fix it as I thought to
+ * do! If using SIG_IGN, the pause() call below would not stop on
+ * SIGWINCH. */
signal(SIGWINCH, winch_handler);
sigfillset(&sigs);
sigdelset(&sigs, SIGWINCH);
+ /* Block anything else than SIGWINCH. */
if(sigprocmask(SIG_SETMASK, &sigs, NULL) < 0){
printk("winch_thread : sigprocmask failed, errno = %d\n",
errno);
exit(1);
}
- if(ioctl(pty_fd, TIOCSCTTY, 0) < 0){
- printk("winch_thread : TIOCSCTTY failed, errno = %d\n", errno);
- exit(1);
- }
- if(tcsetpgrp(pty_fd, os_getpid()) < 0){
- printk("winch_thread : tcsetpgrp failed, errno = %d\n", errno);
+ err = os_new_tty_pgrp(pty_fd, os_getpid());
+ if(err < 0){
+ printk("winch_thread : new_tty_pgrp failed, err = %d\n", -err);
exit(1);
}
- if(read(pipe_fd, &c, sizeof(c)) != sizeof(c))
+ /* These are synchronization calls between various UML threads on the
+ * host - since they are not different kernel threads, we cannot use
+ * kernel semaphores. We don't use SysV semaphores because they are
+ * persistant. */
+ count = os_read_file(pipe_fd, &c, sizeof(c));
+ if(count != sizeof(c))
printk("winch_thread : failed to read synchronization byte, "
- "errno = %d\n", errno);
+ "err = %d\n", -count);
while(1){
+ /* This will be interrupted by SIGWINCH only, since other signals
+ * are blocked.*/
pause();
- if(write(pipe_fd, &c, sizeof(c)) != sizeof(c)){
- printk("winch_thread : write failed, errno = %d\n",
- errno);
- }
+ count = os_write_file(pipe_fd, &c, sizeof(c));
+ if(count != sizeof(c))
+ printk("winch_thread : write failed, err = %d\n",
+ -count);
}
}
-static int winch_tramp(int fd, void *device_data, int *fd_out)
+static int winch_tramp(int fd, struct tty_struct *tty, int *fd_out)
{
struct winch_data data;
unsigned long stack;
char c;
err = os_pipe(fds, 1, 1);
- if(err){
- printk("winch_tramp : os_pipe failed, errno = %d\n", -err);
+ if(err < 0){
+ printk("winch_tramp : os_pipe failed, err = %d\n", -err);
return(err);
}
return(pid);
}
- close(fds[1]);
+ os_close_file(fds[1]);
*fd_out = fds[0];
- n = read(fds[0], &c, sizeof(c));
+ n = os_read_file(fds[0], &c, sizeof(c));
if(n != sizeof(c)){
printk("winch_tramp : failed to read synchronization byte\n");
- printk("read returned %d, errno = %d\n", n, errno);
+ printk("read failed, err = %d\n", -n);
printk("fd %d will not support SIGWINCH\n", fd);
*fd_out = -1;
}
return(pid);
}
-void register_winch(int fd, void *device_data)
+void register_winch(int fd, struct tty_struct *tty)
{
int pid, thread, thread_fd;
+ int count;
char c = 1;
- if(!isatty(fd)) return;
+ if(!isatty(fd))
+ return;
pid = tcgetpgrp(fd);
- if(!CHOOSE_MODE(is_tracer_winch(pid, fd, device_data), 0) &&
- (pid == -1)){
- thread = winch_tramp(fd, device_data, &thread_fd);
+ if(!CHOOSE_MODE_PROC(is_tracer_winch, is_skas_winch, pid, fd,
+ tty) && (pid == -1)){
+ thread = winch_tramp(fd, tty, &thread_fd);
if(fd != -1){
- register_winch_irq(thread_fd, fd, thread, device_data);
+ register_winch_irq(thread_fd, fd, thread, tty);
- if(write(thread_fd, &c, sizeof(c)) != sizeof(c))
+ count = os_write_file(thread_fd, &c, sizeof(c));
+ if(count != sizeof(c))
printk("register_winch : failed to write "
- "synchronization byte\n");
+ "synchronization byte, err = %d\n",
+ -count);
}
}
}
git://git.onelab.eu / linux-2.6.git / blobdiff