freebsd-dev/bin/sh/output.c
Stefan Farfeleder 3f0131f65b Print empty quotes ('') when an empty string is passed to outqstr().
This makes a difference for the trap builtin, where after "trap '' 0" we
printed "trap -- quit".  This is wrong, because an empty action means to reset
the action to the default.  A side effect of this commit is that empty
variables are now printed as "variable=''" instead of just "variable=".
2005-12-08 21:00:39 +00:00

336 lines
6.5 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[] = "@(#)output.c 8.2 (Berkeley) 5/4/95";
#endif
#endif /* not lint */
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
/*
* Shell output routines. We use our own output routines because:
* When a builtin command is interrupted we have to discard
* any pending output.
* When a builtin command appears in back quotes, we want to
* save the output of the command in a region obtained
* via malloc, rather than doing a fork and reading the
* output of the command via a pipe.
*/
#include <stdio.h> /* defines BUFSIZ */
#include <string.h>
#include <stdarg.h>
#include <errno.h>
#include <unistd.h>
#include <stdlib.h>
#include "shell.h"
#include "syntax.h"
#include "output.h"
#include "memalloc.h"
#include "error.h"
#include "var.h"
#define OUTBUFSIZ BUFSIZ
#define BLOCK_OUT -2 /* output to a fixed block of memory */
#define MEM_OUT -3 /* output to dynamically allocated memory */
#define OUTPUT_ERR 01 /* error occurred on output */
static int doformat_wr(void *, const char *, int);
struct output output = {NULL, 0, NULL, OUTBUFSIZ, 1, 0};
struct output errout = {NULL, 0, NULL, 100, 2, 0};
struct output memout = {NULL, 0, NULL, 0, MEM_OUT, 0};
struct output *out1 = &output;
struct output *out2 = &errout;
#ifdef mkinit
INCLUDE "output.h"
INCLUDE "memalloc.h"
RESET {
out1 = &output;
out2 = &errout;
if (memout.buf != NULL) {
ckfree(memout.buf);
memout.buf = NULL;
}
}
#endif
void
out1str(const char *p)
{
outstr(p, out1);
}
void
out1qstr(const char *p)
{
outqstr(p, out1);
}
void
out2str(const char *p)
{
outstr(p, out2);
}
void
out2qstr(const char *p)
{
outqstr(p, out2);
}
void
outstr(const char *p, struct output *file)
{
while (*p)
outc(*p++, file);
if (file == out2)
flushout(file);
}
/* Like outstr(), but quote for re-input into the shell. */
void
outqstr(const char *p, struct output *file)
{
char ch;
if (p[0] == '\0') {
outstr("''", file);
return;
}
if (p[strcspn(p, "|&;<>()$`\\\"'")] == '\0' && (!ifsset() ||
p[strcspn(p, ifsval())] == '\0')) {
outstr(p, file);
return;
}
out1c('\'');
while ((ch = *p++) != '\0') {
switch (ch) {
case '\'':
/*
* Can't quote single quotes inside single quotes;
* close them, write escaped single quote, open again.
*/
outstr("'\\''", file);
break;
default:
outc(ch, file);
}
}
out1c('\'');
}
STATIC char out_junk[16];
void
emptyoutbuf(struct output *dest)
{
int offset;
if (dest->fd == BLOCK_OUT) {
dest->nextc = out_junk;
dest->nleft = sizeof out_junk;
dest->flags |= OUTPUT_ERR;
} else if (dest->buf == NULL) {
INTOFF;
dest->buf = ckmalloc(dest->bufsize);
dest->nextc = dest->buf;
dest->nleft = dest->bufsize;
INTON;
} else if (dest->fd == MEM_OUT) {
offset = dest->bufsize;
INTOFF;
dest->bufsize <<= 1;
dest->buf = ckrealloc(dest->buf, dest->bufsize);
dest->nleft = dest->bufsize - offset;
dest->nextc = dest->buf + offset;
INTON;
} else {
flushout(dest);
}
dest->nleft--;
}
void
flushall(void)
{
flushout(&output);
flushout(&errout);
}
void
flushout(struct output *dest)
{
if (dest->buf == NULL || dest->nextc == dest->buf || dest->fd < 0)
return;
if (xwrite(dest->fd, dest->buf, dest->nextc - dest->buf) < 0)
dest->flags |= OUTPUT_ERR;
dest->nextc = dest->buf;
dest->nleft = dest->bufsize;
}
void
freestdout(void)
{
INTOFF;
if (output.buf) {
ckfree(output.buf);
output.buf = NULL;
output.nleft = 0;
}
INTON;
}
void
outfmt(struct output *file, const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
doformat(file, fmt, ap);
va_end(ap);
}
void
out1fmt(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
doformat(out1, fmt, ap);
va_end(ap);
}
void
dprintf(const char *fmt, ...)
{
va_list ap;
va_start(ap, fmt);
doformat(out2, fmt, ap);
va_end(ap);
flushout(out2);
}
void
fmtstr(char *outbuf, int length, const char *fmt, ...)
{
va_list ap;
struct output strout;
strout.nextc = outbuf;
strout.nleft = length;
strout.fd = BLOCK_OUT;
strout.flags = 0;
va_start(ap, fmt);
doformat(&strout, fmt, ap);
va_end(ap);
outc('\0', &strout);
if (strout.flags & OUTPUT_ERR)
outbuf[length - 1] = '\0';
}
static int
doformat_wr(void *cookie, const char *buf, int len)
{
struct output *o;
int origlen;
unsigned char c;
o = (struct output *)cookie;
origlen = len;
while (len-- != 0) {
c = (unsigned char)*buf++;
outc(c, o);
}
return (origlen);
}
void
doformat(struct output *dest, const char *f, va_list ap)
{
FILE *fp;
if ((fp = fwopen(dest, doformat_wr)) != NULL) {
vfprintf(fp, f, ap);
fclose(fp);
}
}
/*
* Version of write which resumes after a signal is caught.
*/
int
xwrite(int fd, char *buf, int nbytes)
{
int ntry;
int i;
int n;
n = nbytes;
ntry = 0;
for (;;) {
i = write(fd, buf, n);
if (i > 0) {
if ((n -= i) <= 0)
return nbytes;
buf += i;
ntry = 0;
} else if (i == 0) {
if (++ntry > 10)
return nbytes - n;
} else if (errno != EINTR) {
return -1;
}
}
}