freebsd-nq/bin/sh/miscbltin.c
Jilles Tjoelker 40b12a0b78 sh: Remove a comment that was obsoleted by r358152
Since r358152, the read builtin has used a buffer.

Also, remove a space at the end of the line in a comment.

No functional change is intended.
2020-05-22 14:46:23 +00:00

606 lines
13 KiB
C

/*-
* SPDX-License-Identifier: BSD-3-Clause
*
* 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.
* 3. 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 <errno.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include "shell.h"
#include "options.h"
#include "var.h"
#include "output.h"
#include "memalloc.h"
#include "error.h"
#include "mystring.h"
#include "syntax.h"
#include "trap.h"
#undef eflag
#define READ_BUFLEN 1024
struct fdctx {
int fd;
size_t off; /* offset in buf */
size_t buflen;
char *ep; /* tail pointer */
char buf[READ_BUFLEN];
};
static void fdctx_init(int, struct fdctx *);
static void fdctx_destroy(struct fdctx *);
static ssize_t fdgetc(struct fdctx *, char *);
int readcmd(int, char **);
int umaskcmd(int, char **);
int ulimitcmd(int, char **);
static void
fdctx_init(int fd, struct fdctx *fdc)
{
off_t cur;
/* Check if fd is seekable. */
cur = lseek(fd, 0, SEEK_CUR);
*fdc = (struct fdctx){
.fd = fd,
.buflen = (cur != -1) ? READ_BUFLEN : 1,
.ep = &fdc->buf[0], /* No data */
};
}
static ssize_t
fdgetc(struct fdctx *fdc, char *c)
{
ssize_t nread;
if (&fdc->buf[fdc->off] == fdc->ep) {
nread = read(fdc->fd, fdc->buf, fdc->buflen);
if (nread > 0) {
fdc->off = 0;
fdc->ep = fdc->buf + nread;
} else
return (nread);
}
*c = fdc->buf[fdc->off++];
return (1);
}
static void
fdctx_destroy(struct fdctx *fdc)
{
off_t residue;
if (fdc->buflen > 1) {
/*
* Reposition the file offset. Here is the layout of buf:
*
* | off
* v
* |*****************|-------|
* buf ep buf+buflen
* |<- residue ->|
*
* off: current character
* ep: offset just after read(2)
* residue: length for reposition
*/
residue = (fdc->ep - fdc->buf) - fdc->off;
if (residue > 0)
(void) lseek(fdc->fd, -residue, SEEK_CUR);
}
}
/*
* The read builtin. The -r option causes backslashes to be treated like
* ordinary characters.
*
* Note that if IFS=' :' then read x y should work so that:
* 'a b' x='a', y='b'
* ' a b ' x='a', y='b'
* ':b' x='', y='b'
* ':' x='', y=''
* '::' x='', y=''
* ': :' x='', y=''
* ':::' x='', y='::'
* ':b c:' x='', y='b c:'
*/
int
readcmd(int argc __unused, char **argv __unused)
{
char **ap;
int backslash;
char c;
int rflag;
char *prompt;
const char *ifs;
char *p;
int startword;
int status;
int i;
int is_ifs;
int saveall = 0;
ptrdiff_t lastnonifs, lastnonifsws;
struct timeval tv;
char *tvptr;
fd_set ifds;
ssize_t nread;
int sig;
struct fdctx fdctx;
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 = " \t\n";
if (tv.tv_sec >= 0) {
/*
* Wait for something to become available.
*/
FD_ZERO(&ifds);
FD_SET(0, &ifds);
status = select(1, &ifds, NULL, NULL, &tv);
/*
* If there's nothing ready, return an error.
*/
if (status <= 0) {
sig = pendingsig;
return (128 + (sig != 0 ? sig : SIGALRM));
}
}
status = 0;
startword = 2;
backslash = 0;
STARTSTACKSTR(p);
lastnonifs = lastnonifsws = -1;
fdctx_init(STDIN_FILENO, &fdctx);
for (;;) {
c = 0;
nread = fdgetc(&fdctx, &c);
if (nread == -1) {
if (errno == EINTR) {
sig = pendingsig;
if (sig == 0)
continue;
status = 128 + sig;
break;
}
warning("read error: %s", strerror(errno));
status = 2;
break;
} else if (nread != 1) {
status = 1;
break;
}
if (c == '\0')
continue;
CHECKSTRSPACE(1, p);
if (backslash) {
backslash = 0;
if (c != '\n') {
startword = 0;
lastnonifs = lastnonifsws = p - stackblock();
USTPUTC(c, p);
}
continue;
}
if (!rflag && c == '\\') {
backslash++;
continue;
}
if (c == '\n')
break;
if (strchr(ifs, c))
is_ifs = strchr(" \t\n", c) ? 1 : 2;
else
is_ifs = 0;
if (startword != 0) {
if (is_ifs == 1) {
/* Ignore leading IFS whitespace */
if (saveall)
USTPUTC(c, p);
continue;
}
if (is_ifs == 2 && startword == 1) {
/* Only one non-whitespace IFS per word */
startword = 2;
if (saveall) {
lastnonifsws = p - stackblock();
USTPUTC(c, p);
}
continue;
}
}
if (is_ifs == 0) {
/* append this character to the current variable */
startword = 0;
if (saveall)
/* Not just a spare terminator */
saveall++;
lastnonifs = lastnonifsws = p - stackblock();
USTPUTC(c, p);
continue;
}
/* end of variable... */
startword = is_ifs;
if (ap[1] == NULL) {
/* Last variable needs all IFS chars */
saveall++;
if (is_ifs == 2)
lastnonifsws = p - stackblock();
USTPUTC(c, p);
continue;
}
STACKSTRNUL(p);
setvar(*ap, stackblock(), 0);
ap++;
STARTSTACKSTR(p);
lastnonifs = lastnonifsws = -1;
}
fdctx_destroy(&fdctx);
STACKSTRNUL(p);
/*
* Remove trailing IFS chars: always remove whitespace, don't remove
* non-whitespace unless it was naked
*/
if (saveall <= 1)
lastnonifsws = lastnonifs;
stackblock()[lastnonifsws + 1] = '\0';
setvar(*ap, stackblock(), 0);
/* Set any remaining args to "" */
while (*++ap != NULL)
setvar(*ap, "", 0);
return status;
}
int
umaskcmd(int argc __unused, char **argv __unused)
{
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 (is_digit(*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)) == NULL)
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;
short 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
{ "socket buffer size", "bytes", RLIMIT_SBSIZE, 1, 'b' },
#endif
#ifdef RLIMIT_NPTS
{ "pseudo-terminals", (char *)0, RLIMIT_NPTS, 1, 'p' },
#endif
#ifdef RLIMIT_KQUEUES
{ "kqueues", (char *)0, RLIMIT_KQUEUES, 1, 'k' },
#endif
#ifdef RLIMIT_UMTXP
{ "umtx shared locks", (char *)0, RLIMIT_UMTXP, 1, 'o' },
#endif
{ (char *) 0, (char *)0, 0, 0, '\0' }
};
enum limithow { SOFT = 0x1, HARD = 0x2 };
static void
printlimit(enum limithow how, const struct rlimit *limit,
const struct limits *l)
{
rlim_t val = 0;
if (how & SOFT)
val = limit->rlim_cur;
else if (how & HARD)
val = limit->rlim_max;
if (val == RLIM_INFINITY)
out1str("unlimited\n");
else
{
val /= l->factor;
out1fmt("%jd\n", (intmax_t)val);
}
}
int
ulimitcmd(int argc __unused, char **argv __unused)
{
rlim_t val = 0;
enum limithow how = SOFT | HARD;
const struct limits *l;
int set, all = 0;
int optc, what;
struct rlimit limit;
what = 'f';
while ((optc = nextopt("HSatfdsmcnuvlbpwko")) != '\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 {
char *end;
uintmax_t uval;
if (*p < '0' || *p > '9')
error("bad number");
errno = 0;
uval = strtoumax(p, &end, 10);
if (errno != 0 || *end != '\0')
error("bad number");
if (uval > UINTMAX_MAX / l->factor)
error("bad number");
uval *= l->factor;
val = (rlim_t)uval;
if (val < 0 || (uintmax_t)val != uval ||
val == RLIM_INFINITY)
error("bad number");
}
}
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 (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);
printlimit(how, &limit, l);
}
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
printlimit(how, &limit, l);
return 0;
}