source: trunk/minix/commands/ash/output.c@ 15

/*-
 * Copyright (c) 1991 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *      This product includes software developed by the University of
 *      California, Berkeley and its contributors.
 * 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
static char sccsid[] = "@(#)output.c    5.1 (Berkeley) 3/7/91";
#endif /* not lint */

/*
 * 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.
 *      Our output routines may be smaller than the stdio routines.
 */

#include <stdio.h>      /* defines BUFSIZ */
#include "shell.h"
#include "syntax.h"
#include "output.h"
#include "memalloc.h"
#include "error.h"
#ifdef __STDC__
#include "stdarg.h"
#else
#include <varargs.h>
#endif
#include <errno.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 */


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


#ifdef notdef   /* no longer used */
/*
 * Set up an output file to write to memory rather than a file.
 */

void
open_mem(block, length, file)
        char *block;
        int length;
        struct output *file;
        {
        file->nextc = block;
        file->nleft = --length;
        file->fd = BLOCK_OUT;
        file->flags = 0;
}
#endif


void
out1str(p)
        char *p;
        {
        outstr(p, out1);
}


void
out2str(p)
        char *p;
        {
        outstr(p, out2);
}


void
outstr(p, file)
        register char *p;
        register struct output *file;
        {
        while (*p)
                outc(*p++, file);
}


char out_junk[16];


void
emptyoutbuf(dest)
        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() {
        flushout(&output);
        flushout(&errout);
}


void
flushout(dest)
        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() {
        INTOFF;
        if (output.buf) {
                ckfree(output.buf);
                output.buf = NULL;
                output.nleft = 0;
        }
        INTON;
}


#ifdef __STDC__
void
outfmt(struct output *file, char *fmt, ...) {
        va_list ap;

        va_start(ap, fmt);
        doformat(file, fmt, ap);
        va_end(ap);
}


void
out1fmt(char *fmt, ...) {
        va_list ap;

        va_start(ap, fmt);
        doformat(out1, fmt, ap);
        va_end(ap);
}


void
fmtstr(char *outbuf, int length, char *fmt, ...) {
        va_list ap;
        struct output strout;

        va_start(ap, fmt);
        strout.nextc = outbuf;
        strout.nleft = length;
        strout.fd = BLOCK_OUT;
        strout.flags = 0;
        doformat(&strout, fmt, ap);
        outc('\0', &strout);
        if (strout.flags & OUTPUT_ERR)
                outbuf[length - 1] = '\0';
        va_end(ap);
}

#else /* not __STDC__ */

void
outfmt(va_alist)
        va_dcl
        {
        va_list ap;
        struct output *file;
        char *fmt;

        va_start(ap);
        file = va_arg(ap, struct output *);
        fmt = va_arg(ap, char *);
        doformat(file, fmt, ap);
        va_end(ap);
}


void
out1fmt(va_alist)
        va_dcl
        {
        va_list ap;
        char *fmt;

        va_start(ap);
        fmt = va_arg(ap, char *);
        doformat(out1, fmt, ap);
        va_end(ap);
}


void
fmtstr(va_alist)
        va_dcl
        {
        va_list ap;
        struct output strout;
        char *outbuf;
        int length;
        char *fmt;

        va_start(ap);
        outbuf = va_arg(ap, char *);
        length = va_arg(ap, int);
        fmt = va_arg(ap, char *);
        strout.nextc = outbuf;
        strout.nleft = length;
        strout.fd = BLOCK_OUT;
        strout.flags = 0;
        doformat(&strout, fmt, ap);
        outc('\0', &strout);
        if (strout.flags & OUTPUT_ERR)
                outbuf[length - 1] = '\0';
}
#endif /* __STDC__ */


/*
 * Formatted output.  This routine handles a subset of the printf formats:
 * - Formats supported: d, u, o, X, s, and c.
 * - The x format is also accepted but is treated like X.
 * - The l modifier is accepted.
 * - The - and # flags are accepted; # only works with the o format.
 * - Width and precision may be specified with any format except c.
 * - An * may be given for the width or precision.
 * - The obsolete practice of preceding the width with a zero to get
 *   zero padding is not supported; use the precision field.
 * - A % may be printed by writing %% in the format string.
 */

#define TEMPSIZE 24

#ifdef __STDC__
static const char digit[16] = "0123456789ABCDEF";
#else
static const char digit[17] = "0123456789ABCDEF";
#endif


void
doformat(dest, f, ap)
        register struct output *dest;
        register char *f;               /* format string */
        va_list ap;
        {
        register char c;
        char temp[TEMPSIZE];
        int flushleft;
        int sharp;
        int width;
        int prec;
        int islong;
        char *p;
        int sign;
        long l;
        unsigned long num;
        unsigned base;
        int len;
        int size;
        int pad;

        while ((c = *f++) != '\0') {
                if (c != '%') {
                        outc(c, dest);
                        continue;
                }
                flushleft = 0;
                sharp = 0;
                width = 0;
                prec = -1;
                islong = 0;
                for (;;) {
                        if (*f == '-')
                                flushleft++;
                        else if (*f == '#')
                                sharp++;
                        else
                                break;
                        f++;
                }
                if (*f == '*') {
                        width = va_arg(ap, int);
                        f++;
                } else {
                        while (is_digit(*f)) {
                                width = 10 * width + digit_val(*f++);
                        }
                }
                if (*f == '.') {
                        if (*++f == '*') {
                                prec = va_arg(ap, int);
                                f++;
                        } else {
                                prec = 0;
                                while (is_digit(*f)) {
                                        prec = 10 * prec + digit_val(*f++);
                                }
                        }
                }
                if (*f == 'l') {
                        islong++;
                        f++;
                }
                switch (*f) {
                case 'd':
                        if (islong)
                                l = va_arg(ap, long);
                        else
                                l = va_arg(ap, int);
                        sign = 0;
                        num = l;
                        if (l < 0) {
                                num = -l;
                                sign = 1;
                        }
                        base = 10;
                        goto number;
                case 'u':
                        base = 10;
                        goto uns_number;
                case 'o':
                        base = 8;
                        goto uns_number;
                case 'x':
                        /* we don't implement 'x'; treat like 'X' */
                case 'X':
                        base = 16;
uns_number:       /* an unsigned number */
                        sign = 0;
                        if (islong)
                                num = va_arg(ap, unsigned long);
                        else
                                num = va_arg(ap, unsigned int);
number:           /* process a number */
                        p = temp + TEMPSIZE - 1;
                        *p = '\0';
                        while (num) {
                                *--p = digit[num % base];
                                num /= base;
                        }
                        len = (temp + TEMPSIZE - 1) - p;
                        if (prec < 0)
                                prec = 1;
                        if (sharp && *f == 'o' && prec <= len)
                                prec = len + 1;
                        pad = 0;
                        if (width) {
                                size = len;
                                if (size < prec)
                                        size = prec;
                                size += sign;
                                pad = width - size;
                                if (flushleft == 0) {
                                        while (--pad >= 0)
                                                outc(' ', dest);
                                }
                        }
                        if (sign)
                                outc('-', dest);
                        prec -= len;
                        while (--prec >= 0)
                                outc('0', dest);
                        while (*p)
                                outc(*p++, dest);
                        while (--pad >= 0)
                                outc(' ', dest);
                        break;
                case 's':
                        p = va_arg(ap, char *);
                        pad = 0;
                        if (width) {
                                len = strlen(p);
                                if (prec >= 0 && len > prec)
                                        len = prec;
                                pad = width - len;
                                if (flushleft == 0) {
                                        while (--pad >= 0)
                                                outc(' ', dest);
                                }
                        }
                        prec++;
                        while (--prec != 0 && *p)
                                outc(*p++, dest);
                        while (--pad >= 0)
                                outc(' ', dest);
                        break;
                case 'c':
                        c = va_arg(ap, int);
                        outc(c, dest);
                        break;
                default:
                        outc(*f, dest);
                        break;
                }
                f++;
        }
}



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

int
xwrite(fd, buf, nbytes)
        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;
                }
        }
}


/*
 * Version of ioctl that retries after a signal is caught.
 */

int
xioctl(fd, request, arg) {
        int i;

        while ((i = ioctl(fd, request, arg)) == -1 && errno == EINTR);
        return i;
}