freebsd-src/sys/libkern/gets.c
Ruslan Ermilov 90ee1f3a04 Ignore spurious '\0' first character read on a serial console.
This allows me to "boot -a" over a serial console.  Tested on
several machines.
2006-01-14 20:45:02 +00:00

70 lines
2.0 KiB
C

/*-
* Copyright (c) 1999 Michael Smith
* Copyright (c) 2005 Pawel Jakub Dawidek <pjd@FreeBSD.org>
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/cons.h>
#include <sys/libkern.h>
void
gets(char *cp, size_t size, int visible)
{
char *lp, *end;
int c;
lp = cp;
end = cp + size - 1;
for (;;) {
c = cngetc() & 0177;
switch (c) {
case '\n':
case '\r':
printf("%c", c);
*lp = '\0';
return;
case '\b':
case '\177':
if (lp > cp) {
if (visible)
printf("%c \b", c);
lp--;
}
continue;
case '\0':
continue;
default:
if (lp < end) {
if (visible)
printf("%c", c);
*lp++ = c;
}
}
}
}