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// SPDX-License-Identifier: GPL-2.0
#include <linux/kernel.h>
#include <linux/init.h>
#include <linux/console.h>
#include "chan_user.h"
/* ----------------------------------------------------------------------------- */
/* trivial console driver -- simply dump everything to stderr */
/*
* Don't register by default -- as this registers very early in the
* boot process it becomes the default console.
*
* Initialized at init time.
*/
static int use_stderr_console = 0;
static void stderr_console_write(struct console *console, const char *string,
unsigned len)
{
generic_write(2 /* stderr */, string, len, NULL);
}
static struct console stderr_console = {
.name = "stderr",
.write = stderr_console_write,
.flags = CON_PRINTBUFFER,
};
static int __init stderr_console_init(void)
{
if (use_stderr_console)
register_console(&stderr_console);
return 0;
}
console_initcall(stderr_console_init);
static int stderr_setup(char *str)
{
if (!str)
return 0;
use_stderr_console = simple_strtoul(str,&str,0);
return 1;
}
__setup("stderr=", stderr_setup);
/* The previous behavior of not unregistering led to /dev/console being
* impossible to open. My FC5 filesystem started having init die, and the
* system panicing because of this. Unregistering causes the real
* console to become the default console, and /dev/console can then be
* opened. Making this an initcall makes this happen late enough that
* there is no added value in dumping everything to stderr, and the
* normal console is good enough to show you all available output.
*/
static int __init unregister_stderr(void)
{
unregister_console(&stderr_console);
return 0;
}
__initcall(unregister_stderr);
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