freebsd-dev/bin/sh/miscbltin.c
Ed Schouten bc093719ca Integrate the new MPSAFE TTY layer to the FreeBSD operating system.
The last half year I've been working on a replacement TTY layer for the
FreeBSD kernel. The new TTY layer was designed to improve the following:

- Improved driver model:

  The old TTY layer has a driver model that is not abstract enough to
  make it friendly to use. A good example is the output path, where the
  device drivers directly access the output buffers. This means that an
  in-kernel PPP implementation must always convert network buffers into
  TTY buffers.

  If a PPP implementation would be built on top of the new TTY layer
  (still needs a hooks layer, though), it would allow the PPP
  implementation to directly hand the data to the TTY driver.

- Improved hotplugging:

  With the old TTY layer, it isn't entirely safe to destroy TTY's from
  the system. This implementation has a two-step destructing design,
  where the driver first abandons the TTY. After all threads have left
  the TTY, the TTY layer calls a routine in the driver, which can be
  used to free resources (unit numbers, etc).

  The pts(4) driver also implements this feature, which means
  posix_openpt() will now return PTY's that are created on the fly.

- Improved performance:

  One of the major improvements is the per-TTY mutex, which is expected
  to improve scalability when compared to the old Giant locking.
  Another change is the unbuffered copying to userspace, which is both
  used on TTY device nodes and PTY masters.

Upgrading should be quite straightforward. Unlike previous versions,
existing kernel configuration files do not need to be changed, except
when they reference device drivers that are listed in UPDATING.

Obtained from:		//depot/projects/mpsafetty/...
Approved by:		philip (ex-mentor)
Discussed:		on the lists, at BSDCan, at the DevSummit
Sponsored by:		Snow B.V., the Netherlands
dcons(4) fixed by:	kan
2008-08-20 08:31:58 +00:00

459 lines
9.6 KiB
C

/*-
* Copyright (c) 1991, 1993
* The Regents of the University of California. All rights reserved.
*
* This code is derived from software contributed to Berkeley by
* Kenneth Almquist.
*
* 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.
*/
#ifndef lint
#if 0
static char sccsid[] = "@(#)miscbltin.c 8.4 (Berkeley) 5/4/95";
#endif
#endif /* not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Miscellaneous builtins.
*/
#include <sys/types.h>
#include <sys/stat.h>
#include <sys/time.h>
#include <sys/resource.h>
#include <unistd.h>
#include <ctype.h>
#include <errno.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <termios.h>
#include "shell.h"
#include "options.h"
#include "var.h"
#include "output.h"
#include "memalloc.h"
#include "error.h"
#include "mystring.h"
#undef eflag
int readcmd(int, char **);
int umaskcmd(int, char **);
int ulimitcmd(int, char **);
/*
* The read builtin. The -r option causes backslashes to be treated like
* ordinary characters.
*
* This uses unbuffered input, which may be avoidable in some cases.
*/
int
readcmd(int argc __unused, char **argv __unused)
{
char **ap;
int backslash;
char c;
int rflag;
char *prompt;
char *ifs;
char *p;
int startword;
int status;
int i;
struct timeval tv;
char *tvptr;
fd_set ifds;
struct termios told, tnew;
int tsaved;
rflag = 0;
prompt = NULL;
tv.tv_sec = -1;
tv.tv_usec = 0;
while ((i = nextopt("erp:t:")) != '\0') {
switch(i) {
case 'p':
prompt = shoptarg;
break;
case 'e':
break;
case 'r':
rflag = 1;
break;
case 't':
tv.tv_sec = strtol(shoptarg, &tvptr, 0);
if (tvptr == shoptarg)
error("timeout value");
switch(*tvptr) {
case 0:
case 's':
break;
case 'h':
tv.tv_sec *= 60;
/* FALLTHROUGH */
case 'm':
tv.tv_sec *= 60;
break;
default:
error("timeout unit");
}
break;
}
}
if (prompt && isatty(0)) {
out2str(prompt);
flushall();
}
if (*(ap = argptr) == NULL)
error("arg count");
if ((ifs = bltinlookup("IFS", 1)) == NULL)
ifs = nullstr;
if (tv.tv_sec >= 0) {
/*
* See if we can disable input processing; this will
* not give the desired result if we are in a pipeline
* and someone upstream is still in line-by-line mode.
*/
tsaved = 0;
if (tcgetattr(0, &told) == 0) {
memcpy(&tnew, &told, sizeof(told));
cfmakeraw(&tnew);
tcsetattr(0, TCSANOW, &tnew);
tsaved = 1;
}
/*
* Wait for something to become available.
*/
FD_ZERO(&ifds);
FD_SET(0, &ifds);
status = select(1, &ifds, NULL, NULL, &tv);
if (tsaved)
tcsetattr(0, TCSANOW, &told);
/*
* If there's nothing ready, return an error.
*/
if (status <= 0)
return(1);
}
status = 0;
startword = 1;
backslash = 0;
STARTSTACKSTR(p);
for (;;) {
if (read(STDIN_FILENO, &c, 1) != 1) {
status = 1;
break;
}
if (c == '\0')
continue;
if (backslash) {
backslash = 0;
if (c != '\n')
STPUTC(c, p);
continue;
}
if (!rflag && c == '\\') {
backslash++;
continue;
}
if (c == '\n')
break;
if (startword && *ifs == ' ' && strchr(ifs, c)) {
continue;
}
startword = 0;
if (ap[1] != NULL && strchr(ifs, c) != NULL) {
STACKSTRNUL(p);
setvar(*ap, stackblock(), 0);
ap++;
startword = 1;
STARTSTACKSTR(p);
} else {
STPUTC(c, p);
}
}
STACKSTRNUL(p);
setvar(*ap, stackblock(), 0);
while (*++ap != NULL)
setvar(*ap, nullstr, 0);
return status;
}
int
umaskcmd(int argc __unused, char **argv)
{
char *ap;
int mask;
int i;
int symbolic_mode = 0;
while ((i = nextopt("S")) != '\0') {
symbolic_mode = 1;
}
INTOFF;
mask = umask(0);
umask(mask);
INTON;
if ((ap = *argptr) == NULL) {
if (symbolic_mode) {
char u[4], g[4], o[4];
i = 0;
if ((mask & S_IRUSR) == 0)
u[i++] = 'r';
if ((mask & S_IWUSR) == 0)
u[i++] = 'w';
if ((mask & S_IXUSR) == 0)
u[i++] = 'x';
u[i] = '\0';
i = 0;
if ((mask & S_IRGRP) == 0)
g[i++] = 'r';
if ((mask & S_IWGRP) == 0)
g[i++] = 'w';
if ((mask & S_IXGRP) == 0)
g[i++] = 'x';
g[i] = '\0';
i = 0;
if ((mask & S_IROTH) == 0)
o[i++] = 'r';
if ((mask & S_IWOTH) == 0)
o[i++] = 'w';
if ((mask & S_IXOTH) == 0)
o[i++] = 'x';
o[i] = '\0';
out1fmt("u=%s,g=%s,o=%s\n", u, g, o);
} else {
out1fmt("%.4o\n", mask);
}
} else {
if (isdigit(*ap)) {
mask = 0;
do {
if (*ap >= '8' || *ap < '0')
error("Illegal number: %s", *argptr);
mask = (mask << 3) + (*ap - '0');
} while (*++ap != '\0');
umask(mask);
} else {
void *set;
INTOFF;
if ((set = setmode (ap)) == 0)
error("Illegal number: %s", ap);
mask = getmode (set, ~mask & 0777);
umask(~mask & 0777);
free(set);
INTON;
}
}
return 0;
}
/*
* ulimit builtin
*
* This code, originally by Doug Gwyn, Doug Kingston, Eric Gisin, and
* Michael Rendell was ripped from pdksh 5.0.8 and hacked for use with
* ash by J.T. Conklin.
*
* Public domain.
*/
struct limits {
const char *name;
const char *units;
int cmd;
int factor; /* multiply by to get rlim_{cur,max} values */
char option;
};
static const struct limits limits[] = {
#ifdef RLIMIT_CPU
{ "cpu time", "seconds", RLIMIT_CPU, 1, 't' },
#endif
#ifdef RLIMIT_FSIZE
{ "file size", "512-blocks", RLIMIT_FSIZE, 512, 'f' },
#endif
#ifdef RLIMIT_DATA
{ "data seg size", "kbytes", RLIMIT_DATA, 1024, 'd' },
#endif
#ifdef RLIMIT_STACK
{ "stack size", "kbytes", RLIMIT_STACK, 1024, 's' },
#endif
#ifdef RLIMIT_CORE
{ "core file size", "512-blocks", RLIMIT_CORE, 512, 'c' },
#endif
#ifdef RLIMIT_RSS
{ "max memory size", "kbytes", RLIMIT_RSS, 1024, 'm' },
#endif
#ifdef RLIMIT_MEMLOCK
{ "locked memory", "kbytes", RLIMIT_MEMLOCK, 1024, 'l' },
#endif
#ifdef RLIMIT_NPROC
{ "max user processes", (char *)0, RLIMIT_NPROC, 1, 'u' },
#endif
#ifdef RLIMIT_NOFILE
{ "open files", (char *)0, RLIMIT_NOFILE, 1, 'n' },
#endif
#ifdef RLIMIT_VMEM
{ "virtual mem size", "kbytes", RLIMIT_VMEM, 1024, 'v' },
#endif
#ifdef RLIMIT_SWAP
{ "swap limit", "kbytes", RLIMIT_SWAP, 1024, 'w' },
#endif
#ifdef RLIMIT_SBSIZE
{ "sbsize", "bytes", RLIMIT_SBSIZE, 1, 'b' },
#endif
#ifdef RLIMIT_NPTS
{ "pseudo-terminals", (char *)0, RLIMIT_NPTS, 1, 'p' },
#endif
{ (char *) 0, (char *)0, 0, 0, '\0' }
};
int
ulimitcmd(int argc __unused, char **argv __unused)
{
int c;
rlim_t val = 0;
enum { SOFT = 0x1, HARD = 0x2 }
how = SOFT | HARD;
const struct limits *l;
int set, all = 0;
int optc, what;
struct rlimit limit;
what = 'f';
while ((optc = nextopt("HSatfdsmcnuvlbp")) != '\0')
switch (optc) {
case 'H':
how = HARD;
break;
case 'S':
how = SOFT;
break;
case 'a':
all = 1;
break;
default:
what = optc;
}
for (l = limits; l->name && l->option != what; l++)
;
if (!l->name)
error("internal error (%c)", what);
set = *argptr ? 1 : 0;
if (set) {
char *p = *argptr;
if (all || argptr[1])
error("too many arguments");
if (strcmp(p, "unlimited") == 0)
val = RLIM_INFINITY;
else {
val = 0;
while ((c = *p++) >= '0' && c <= '9')
{
val = (val * 10) + (long)(c - '0');
if (val < 0)
break;
}
if (c)
error("bad number");
val *= l->factor;
}
}
if (all) {
for (l = limits; l->name; l++) {
char optbuf[40];
if (getrlimit(l->cmd, &limit) < 0)
error("can't get limit: %s", strerror(errno));
if (how & SOFT)
val = limit.rlim_cur;
else if (how & HARD)
val = limit.rlim_max;
if (l->units)
snprintf(optbuf, sizeof(optbuf),
"(%s, -%c) ", l->units, l->option);
else
snprintf(optbuf, sizeof(optbuf),
"(-%c) ", l->option);
out1fmt("%-18s %18s ", l->name, optbuf);
if (val == RLIM_INFINITY)
out1fmt("unlimited\n");
else
{
val /= l->factor;
out1fmt("%jd\n", (intmax_t)val);
}
}
return 0;
}
if (getrlimit(l->cmd, &limit) < 0)
error("can't get limit: %s", strerror(errno));
if (set) {
if (how & SOFT)
limit.rlim_cur = val;
if (how & HARD)
limit.rlim_max = val;
if (setrlimit(l->cmd, &limit) < 0)
error("bad limit: %s", strerror(errno));
} else {
if (how & SOFT)
val = limit.rlim_cur;
else if (how & HARD)
val = limit.rlim_max;
if (val == RLIM_INFINITY)
out1fmt("unlimited\n");
else
{
val /= l->factor;
out1fmt("%jd\n", (intmax_t)val);
}
}
return 0;
}