/*-
 * 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.
 */

/*
 * 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 <wchar.h>
#include <wctype.h>

#include "shell.h"
#include "syntax.h"
#include "output.h"
#include "memalloc.h"
#include "error.h"
#include "var.h"


#define OUTBUFSIZ BUFSIZ
#define MEM_OUT -2              /* 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, NULL, NULL, OUTBUFSIZ, 1, 0};
struct output errout = {NULL, NULL, NULL, 256, 2, 0};
struct output memout = {NULL, NULL, NULL, 64, MEM_OUT, 0};
struct output *out1 = &output;
struct output *out2 = &errout;

void
outcslow(int c, struct output *file)
{
        outc(c, file);
}

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)
{
        outbin(p, strlen(p), file);
}

static void
byteseq(int ch, struct output *file)
{
        char seq[4];

        seq[0] = '\\';
        seq[1] = (ch >> 6 & 0x3) + '0';
        seq[2] = (ch >> 3 & 0x7) + '0';
        seq[3] = (ch & 0x7) + '0';
        outbin(seq, 4, file);
}

static void
outdqstr(const char *p, struct output *file)
{
        const char *end;
        mbstate_t mbs;
        size_t clen;
        wchar_t wc;

        memset(&mbs, '\0', sizeof(mbs));
        end = p + strlen(p);
        outstr("$'", file);
        while ((clen = mbrtowc(&wc, p, end - p + 1, &mbs)) != 0) {
                if (clen == (size_t)-2) {
                        while (p < end)
                                byteseq(*p++, file);
                        break;
                }
                if (clen == (size_t)-1) {
                        memset(&mbs, '\0', sizeof(mbs));
                        byteseq(*p++, file);
                        continue;
                }
                if (wc == L'\n')
                        outcslow('\n', file), p++;
                else if (wc == L'\r')
                        outstr("\\r", file), p++;
                else if (wc == L'\t')
                        outstr("\\t", file), p++;
                else if (!iswprint(wc)) {
                        for (; clen > 0; clen--)
                                byteseq(*p++, file);
                } else {
                        if (wc == L'\'' || wc == L'\\')
                                outcslow('\\', file);
                        outbin(p, clen, file);
                        p += clen;
                }
        }
        outcslow('\'', file);
}

/* Like outstr(), but quote for re-input into the shell. */
void
outqstr(const char *p, struct output *file)
{
        int i;

        if (p[0] == '\0') {
                outstr("''", file);
                return;
        }
        for (i = 0; p[i] != '\0'; i++) {
                if ((p[i] > '\0' && p[i] < ' ' && p[i] != '\n') ||
                    (p[i] & 0x80) != 0 || p[i] == '\'') {
                        outdqstr(p, file);
                        return;
                }
        }

        if (p[strcspn(p, "|&;<>()$`\\\" \n*?[~#=")] == '\0' ||
                        strcmp(p, "[") == 0) {
                outstr(p, file);
                return;
        }

        outcslow('\'', file);
        outstr(p, file);
        outcslow('\'', file);
}

void
outbin(const void *data, size_t len, struct output *file)
{
        const char *p;

        p = data;
        while (len-- > 0)
                outc(*p++, file);
}

void
emptyoutbuf(struct output *dest)
{
        int offset, newsize;

        if (dest->buf == NULL) {
                INTOFF;
                dest->buf = ckmalloc(dest->bufsize);
                dest->nextc = dest->buf;
                dest->bufend = dest->buf + dest->bufsize;
                INTON;
        } else if (dest->fd == MEM_OUT) {
                offset = dest->nextc - dest->buf;
                newsize = dest->bufsize << 1;
                INTOFF;
                dest->buf = ckrealloc(dest->buf, newsize);
                dest->bufsize = newsize;
                dest->bufend = dest->buf + newsize;
                dest->nextc = dest->buf + offset;
                INTON;
        } else {
                flushout(dest);
        }
}


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;
}


void
freestdout(void)
{
        output.nextc = output.buf;
}


int
outiserror(struct output *file)
{
        return (file->flags & OUTPUT_ERR);
}


void
outclearerror(struct output *file)
{
        file->flags &= ~OUTPUT_ERR;
}


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
out2fmt_flush(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;

        INTOFF;
        va_start(ap, fmt);
        vsnprintf(outbuf, length, fmt, ap);
        va_end(ap);
        INTON;
}

static int
doformat_wr(void *cookie, const char *buf, int len)
{
        struct output *o;

        o = (struct output *)cookie;
        outbin(buf, len, o);

        return (len);
}

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);
        }
}

FILE *
out1fp(void)
{
        return fwopen(out1, doformat_wr);
}

/*
 * Version of write which resumes after a signal is caught.
 */

int
xwrite(int fd, const 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;
                }
        }
}