int get_console_fd(char* tty_name)
{
int fd;
if (tty_name)
{
if (-1 == (fd = open_a_console(tty_name)))
return -1;
else
return fd;
}
fd = open_a_console("/dev/tty");
if (fd >= 0)
return fd;
fd = open_a_console("/dev/tty0");
if (fd >= 0)
return fd;
fd = open_a_console("/dev/console");
if (fd >= 0)
return fd;
for (fd = 0; fd < 3; fd++)
if (is_a_console(fd))
return fd;
fprintf(stderr,
"Couldnt get a file descriptor referring to the console\n");
return -1; /* total failure */
}
//=========================================
// getfd...
//-----------------------------------------
int getfd(void) {
int fd;
fd = open_a_console("/dev/tty");
if (fd >= 0) {
return fd;
}
fd = open_a_console("/dev/tty0");
if (fd >= 0) {
return fd;
}
fd = open_a_console("/dev/console");
if (fd >= 0) {
return fd;
}
for (fd = 0; fd < 3; fd++) {
if (is_a_console(fd)) {
return fd;
}
}
fprintf(
stderr,"could not get a console file descriptor\n"
);
exit(1);
}
static int open_a_console(char *fnam)
{
int fd;
/* try read-only */
fd = open(fnam, O_RDWR);
/* if failed, try read-only */
if (fd < 0 && errno == EACCES)
fd = open(fnam, O_RDONLY);
/* if failed, try write-only */
if (fd < 0 && errno == EACCES)
fd = open(fnam, O_WRONLY);
/* if failed, fail */
if (fd < 0)
return -1;
/* if not a console, fail */
if (! is_a_console(fd))
{
close(fd);
return -1;
}
/* success */
return fd;
}
int getfd (const char * const nm) {
int fd;
if (nm) {
fd = open_a_console(nm);
if (fd >= 0)
return fd;
} else {
fd = open_a_console("/dev/tty");
if (fd >= 0)
return fd;
fd = open_a_console("/dev/tty0");
if (fd >= 0)
return fd;
fd = open_a_console("/dev/console");
if (fd >= 0)
return fd;
for (fd = 0; fd < 3; fd++)
if (is_a_console(fd))
return fd;
}
fprintf(stderr,
"Couldnt get a file descriptor referring to the console\n");
exit(1); /* total failure */
}
static void reopen_console_handle(DWORD std, int fd, FILE *stream)
{
if (is_a_console(GetStdHandle(std))) {
freopen("CONOUT$", "wt", stream);
dup2(fileno(stream), fd);
setvbuf(stream, NULL, _IONBF, 0);
}
}
//=========================================
// open_a_console...
//-----------------------------------------
int open_a_console(char *fnam) {
int fd;
fd = open(fnam, O_RDONLY);
if (fd < 0 && errno == EACCES) {
fd = open(fnam, O_WRONLY);
}
if (fd < 0 || ! is_a_console(fd)) {
return -1;
}
return fd;
}
/* FIXME: Only on the current console? On all allocated consoles?
* A newly allocated console has NORM_MAP by default -
* probably it should copy the default from the current console?
* But what if we want a new one because the current one is messed up?
* For the moment: only the current console
* g_set specifies eight G0 or G1 using values 0 and 1 respectively.
*/
int acm_activate(int tty_fd, int g_set)
{
if (is_a_console(tty_fd))
if (g_set == 0)
write(tty_fd, "\033(K\017", 4);
else
write(tty_fd, "\033)K\016", 4);
else
{
errno = ENODEV;
return -1;
}
return 0;
}
static int
open_a_console(const char * const fnam) {
int fd;
fd = open(fnam, O_RDONLY);
if (fd < 0 && errno == EACCES)
fd = open(fnam, O_WRONLY);
if (fd < 0)
return -1;
if (!is_a_console(fd)) {
close(fd);
return -1;
}
return fd;
}
