freebsd-dev/lib/libc/gen/getttyent.c
Nathan Whitehorn 0894229871 Add a new flag to /etc/ttys: onifconsole. This is equivalent to "on" if the
device is an active kernel console and "off" otherwise. This is designed to
allow serial-booting x86 systems to provide a login prompt on the serial line
by default without providing one on all systems by default.

Comments and suggestions by:	grehan, dteske, jilles
MFC after:	1 month
2014-01-20 18:15:06 +00:00

293 lines
6.3 KiB
C

/*
* Copyright (c) 1989, 1993
* The Regents of the University of California. 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.
* 4. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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.
*/
#if defined(LIBC_SCCS) && !defined(lint)
static char sccsid[] = "@(#)getttyent.c 8.1 (Berkeley) 6/4/93";
#endif /* LIBC_SCCS and not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <ttyent.h>
#include <stdio.h>
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
#include <sys/types.h>
#include <sys/sysctl.h>
static char zapchar;
static FILE *tf;
static size_t lbsize;
static char *line;
#define MALLOCCHUNK 100
static char *skip(char *);
static char *value(char *);
struct ttyent *
getttynam(const char *tty)
{
struct ttyent *t;
if (strncmp(tty, "/dev/", 5) == 0)
tty += 5;
setttyent();
while ( (t = getttyent()) )
if (!strcmp(tty, t->ty_name))
break;
endttyent();
return (t);
}
static int
auto_tty_status(const char *ty_name)
{
size_t len;
char *buf, *cons, *nextcons;
/* Check if this is an enabled kernel console line */
buf = NULL;
if (sysctlbyname("kern.console", NULL, &len, NULL, 0) == -1)
return (0); /* Errors mean don't enable */
buf = malloc(len);
if (sysctlbyname("kern.console", buf, &len, NULL, 0) == -1)
goto done;
if ((cons = strchr(buf, '/')) == NULL)
goto done;
*cons = '\0';
nextcons = buf;
while ((cons = strsep(&nextcons, ",")) != NULL && strlen(cons) != 0) {
if (strcmp(cons, ty_name) == 0) {
free(buf);
return (TTY_ON);
}
}
done:
free(buf);
return (0);
}
struct ttyent *
getttyent(void)
{
static struct ttyent tty;
char *p;
int c;
size_t i;
if (!tf && !setttyent())
return (NULL);
for (;;) {
if (!fgets(p = line, lbsize, tf))
return (NULL);
/* extend buffer if line was too big, and retry */
while (!strchr(p, '\n') && !feof(tf)) {
i = strlen(p);
lbsize += MALLOCCHUNK;
if ((p = realloc(line, lbsize)) == NULL) {
(void)endttyent();
return (NULL);
}
line = p;
if (!fgets(&line[i], lbsize - i, tf))
return (NULL);
}
while (isspace((unsigned char)*p))
++p;
if (*p && *p != '#')
break;
}
#define scmp(e) !strncmp(p, e, sizeof(e) - 1) && isspace((unsigned char)p[sizeof(e) - 1])
#define vcmp(e) !strncmp(p, e, sizeof(e) - 1) && p[sizeof(e) - 1] == '='
zapchar = 0;
tty.ty_name = p;
tty.ty_status = 0;
tty.ty_window = NULL;
tty.ty_group = _TTYS_NOGROUP;
p = skip(p);
if (!*(tty.ty_getty = p))
tty.ty_getty = tty.ty_type = NULL;
else {
p = skip(p);
if (!*(tty.ty_type = p))
tty.ty_type = NULL;
else {
/* compatibility kludge: handle network/dialup specially */
if (scmp(_TTYS_DIALUP))
tty.ty_status |= TTY_DIALUP;
else if (scmp(_TTYS_NETWORK))
tty.ty_status |= TTY_NETWORK;
p = skip(p);
}
}
for (; *p; p = skip(p)) {
if (scmp(_TTYS_OFF))
tty.ty_status &= ~TTY_ON;
else if (scmp(_TTYS_ON))
tty.ty_status |= TTY_ON;
else if (scmp(_TTYS_ONIFCONSOLE))
tty.ty_status |= auto_tty_status(tty.ty_name);
else if (scmp(_TTYS_SECURE))
tty.ty_status |= TTY_SECURE;
else if (scmp(_TTYS_INSECURE))
tty.ty_status &= ~TTY_SECURE;
else if (scmp(_TTYS_DIALUP))
tty.ty_status |= TTY_DIALUP;
else if (scmp(_TTYS_NETWORK))
tty.ty_status |= TTY_NETWORK;
else if (vcmp(_TTYS_WINDOW))
tty.ty_window = value(p);
else if (vcmp(_TTYS_GROUP))
tty.ty_group = value(p);
else
break;
}
if (zapchar == '#' || *p == '#')
while ((c = *++p) == ' ' || c == '\t')
;
tty.ty_comment = p;
if (*p == 0)
tty.ty_comment = 0;
if ((p = strchr(p, '\n')))
*p = '\0';
return (&tty);
}
#define QUOTED 1
/*
* Skip over the current field, removing quotes, and return a pointer to
* the next field.
*/
static char *
skip(char *p)
{
char *t;
int c, q;
for (q = 0, t = p; (c = *p) != '\0'; p++) {
if (c == '"') {
q ^= QUOTED; /* obscure, but nice */
continue;
}
if (q == QUOTED && *p == '\\' && *(p+1) == '"')
p++;
*t++ = *p;
if (q == QUOTED)
continue;
if (c == '#') {
zapchar = c;
*p = 0;
break;
}
if (c == '\t' || c == ' ' || c == '\n') {
zapchar = c;
*p++ = 0;
while ((c = *p) == '\t' || c == ' ' || c == '\n')
p++;
break;
}
}
*--t = '\0';
return (p);
}
static char *
value(char *p)
{
return ((p = strchr(p, '=')) ? ++p : NULL);
}
int
setttyent(void)
{
if (line == NULL) {
if ((line = malloc(MALLOCCHUNK)) == NULL)
return (0);
lbsize = MALLOCCHUNK;
}
if (tf) {
rewind(tf);
return (1);
} else if ( (tf = fopen(_PATH_TTYS, "re")) )
return (1);
return (0);
}
int
endttyent(void)
{
int rval;
/*
* NB: Don't free `line' because getttynam()
* may still be referencing it
*/
if (tf) {
rval = (fclose(tf) != EOF);
tf = NULL;
return (rval);
}
return (1);
}
static int
isttystat(const char *tty, int flag)
{
struct ttyent *t;
return ((t = getttynam(tty)) == NULL) ? 0 : !!(t->ty_status & flag);
}
int
isdialuptty(const char *tty)
{
return isttystat(tty, TTY_DIALUP);
}
int
isnettty(const char *tty)
{
return isttystat(tty, TTY_NETWORK);
}