/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1990, 1993
 *      The Regents of the University of California.  All rights reserved.
 *
 * 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.
 */

#include <sys/types.h>

#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <float.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "hexdump.h"

#define PADDING "         "

int odmode;

static void odadd(const char *);
static void odformat(const char *);
static const char *odformatfp(char, const char *);
static const char *odformatint(char, const char *);
static void odoffset(int, char ***);
static void odusage(void);

void
oldsyntax(int argc, char ***argvp)
{
        static char empty[] = "", padding[] = PADDING;
        int ch;
        char **argv, *end;

        /* Add initial (default) address format. -A may change it later. */
#define TYPE_OFFSET     7
        add("\"%07.7_Ao\n\"");
        add("\"%07.7_ao  \"");

        odmode = 1;
        argv = *argvp;
        while ((ch = getopt(argc, argv, "A:aBbcDdeFfHhIij:LlN:Oost:vXx")) != -1)
                switch (ch) {
                case 'A':
                        switch (*optarg) {
                        case 'd': case 'o': case 'x':
                                fshead->nextfu->fmt[TYPE_OFFSET] = *optarg;
                                fshead->nextfs->nextfu->fmt[TYPE_OFFSET] =
                                    *optarg;
                                break;
                        case 'n':
                                fshead->nextfu->fmt = empty;
                                fshead->nextfs->nextfu->fmt = padding;
                                break;
                        default:
                                errx(1, "%s: invalid address base", optarg);
                        }
                        break;
                case 'a':
                        odformat("a");
                        break;
                case 'B':
                case 'o':
                        odformat("o2");
                        break;
                case 'b':
                        odformat("o1");
                        break;
                case 'c':
                        odformat("c");
                        break;
                case 'd':
                        odformat("u2");
                        break;
                case 'D':
                        odformat("u4");
                        break;
                case 'e':               /* undocumented in od */
                case 'F':
                        odformat("fD");
                        break;
                case 'f':
                        odformat("fF");
                        break;
                case 'H':
                case 'X':
                        odformat("x4");
                        break;
                case 'h':
                case 'x':
                        odformat("x2");
                        break;
                case 'I':
                case 'L':
                case 'l':
                        odformat("dL");
                        break;
                case 'i':
                        odformat("dI");
                        break;
                case 'j':
                        errno = 0;
                        skip = strtoll(optarg, &end, 0);
                        if (*end == 'b')
                                skip *= 512;
                        else if (*end == 'k')
                                skip *= 1024;
                        else if (*end == 'm')
                                skip *= 1048576L;
                        if (errno != 0 || skip < 0 || strlen(end) > 1)
                                errx(1, "%s: invalid skip amount", optarg);
                        break;
                case 'N':
                        if ((length = atoi(optarg)) <= 0)
                                errx(1, "%s: invalid length", optarg);
                        break;
                case 'O':
                        odformat("o4");
                        break;
                case 's':
                        odformat("d2");
                        break;
                case 't':
                        odformat(optarg);
                        break;
                case 'v':
                        vflag = ALL;
                        break;
                case '?':
                default:
                        odusage();
                }

        if (fshead->nextfs->nextfs == NULL)
                odformat("oS");

        argc -= optind;
        *argvp += optind;

        if (argc)
                odoffset(argc, argvp);
}

static void
odusage(void)
{

        fprintf(stderr,
"usage: od [-aBbcDdeFfHhIiLlOosvXx] [-A base] [-j skip] [-N length] [-t type]\n");
        fprintf(stderr,
"          [[+]offset[.][Bb]] [file ...]\n");
        exit(1);
}

static void
odoffset(int argc, char ***argvp)
{
        char *p, *num, *end;
        int base;

        /*
         * The offset syntax of od(1) was genuinely bizarre.  First, if
         * it started with a plus it had to be an offset.  Otherwise, if
         * there were at least two arguments, a number or lower-case 'x'
         * followed by a number makes it an offset.  By default it was
         * octal; if it started with 'x' or '0x' it was hex.  If it ended
         * in a '.', it was decimal.  If a 'b' or 'B' was appended, it
         * multiplied the number by 512 or 1024 byte units.  There was
         * no way to assign a block count to a hex offset.
         *
         * We assume it's a file if the offset is bad.
         */
        p = argc == 1 ? (*argvp)[0] : (*argvp)[1];

        if (*p != '+' && (argc < 2 ||
            (!isdigit(p[0]) && (p[0] != 'x' || !isxdigit(p[1])))))
                return;

        base = 0;
        /*
         * skip over leading '+', 'x[0-9a-fA-f]' or '0x', and
         * set base.
         */
        if (p[0] == '+')
                ++p;
        if (p[0] == 'x' && isxdigit(p[1])) {
                ++p;
                base = 16;
        } else if (p[0] == '0' && p[1] == 'x') {
                p += 2;
                base = 16;
        }

        /* skip over the number */
        if (base == 16)
                for (num = p; isxdigit(*p); ++p);
        else
                for (num = p; isdigit(*p); ++p);

        /* check for no number */
        if (num == p)
                return;

        /* if terminates with a '.', base is decimal */
        if (*p == '.') {
                if (base)
                        return;
                base = 10;
        }

        skip = strtoll(num, &end, base ? base : 8);

        /* if end isn't the same as p, we got a non-octal digit */
        if (end != p) {
                skip = 0;
                return;
        }

        if (*p) {
                if (*p == 'B') {
                        skip *= 1024;
                        ++p;
                } else if (*p == 'b') {
                        skip *= 512;
                        ++p;
                }
        }

        if (*p) {
                skip = 0;
                return;
        }

        /*
         * If the offset uses a non-octal base, the base of the offset
         * is changed as well.  This isn't pretty, but it's easy.
         */
        if (base == 16) {
                fshead->nextfu->fmt[TYPE_OFFSET] = 'x';
                fshead->nextfs->nextfu->fmt[TYPE_OFFSET] = 'x';
        } else if (base == 10) {
                fshead->nextfu->fmt[TYPE_OFFSET] = 'd';
                fshead->nextfs->nextfu->fmt[TYPE_OFFSET] = 'd';
        }

        /* Terminate file list. */
        (*argvp)[1] = NULL;
}

static void
odformat(const char *fmt)
{
        char fchar;

        while (*fmt != '\0') {
                switch ((fchar = *fmt++)) {
                case 'a':
                        odadd("16/1 \"%3_u \" \"\\n\"");
                        break;
                case 'c':
                        odadd("16/1 \"%3_c \" \"\\n\"");
                        break;
                case 'o': case 'u': case 'd': case 'x':
                        fmt = odformatint(fchar, fmt);
                        break;
                case 'f':
                        fmt = odformatfp(fchar, fmt);
                        break;
                default:
                        errx(1, "%c: unrecognised format character", fchar);
                }
        }
}

static const char *
odformatfp(char fchar __unused, const char *fmt)
{
        size_t isize;
        int digits;
        char *end, *hdfmt;

        isize = sizeof(double);
        switch (*fmt) {
        case 'F':
                isize = sizeof(float);
                fmt++;
                break;
        case 'D':
                isize = sizeof(double);
                fmt++;
                break;
        case 'L':
                isize = sizeof(long double);
                fmt++;
                break;
        default:
                if (isdigit((unsigned char)*fmt)) {
                        errno = 0;
                        isize = (size_t)strtoul(fmt, &end, 10);
                        if (errno != 0 || isize == 0)
                                errx(1, "%s: invalid size", fmt);
                        fmt = (const char *)end;
                }
        }
        switch (isize) {
        case sizeof(float):
                digits = FLT_DIG;
                break;
        case sizeof(double):
                digits = DBL_DIG;
                break;
        default:
                if (isize == sizeof(long double))
                        digits = LDBL_DIG;
                else
                        errx(1, "unsupported floating point size %lu",
                            (u_long)isize);
        }

        asprintf(&hdfmt, "%lu/%lu \" %%%d.%de \" \"\\n\"",
            16UL / (u_long)isize, (u_long)isize, digits + 8, digits);
        if (hdfmt == NULL)
                err(1, NULL);
        odadd(hdfmt);
        free(hdfmt);

        return (fmt);
}

static const char *
odformatint(char fchar, const char *fmt)
{
        unsigned long long n;
        size_t isize;
        int digits;
        char *end, *hdfmt;

        isize = sizeof(int);
        switch (*fmt) {
        case 'C':
                isize = sizeof(char);
                fmt++;
                break;
        case 'I':
                isize = sizeof(int);
                fmt++;
                break;
        case 'L':
                isize = sizeof(long);
                fmt++;
                break;
        case 'S':
                isize = sizeof(short);
                fmt++;
                break;
        default:
                if (isdigit((unsigned char)*fmt)) {
                        errno = 0;
                        isize = (size_t)strtoul(fmt, &end, 10);
                        if (errno != 0 || isize == 0)
                                errx(1, "%s: invalid size", fmt);
                        if (isize != sizeof(char) && isize != sizeof(short) &&
                            isize != sizeof(int) && isize != sizeof(long))
                                errx(1, "unsupported int size %lu",
                                    (u_long)isize);
                        fmt = (const char *)end;
                }
        }

        /*
         * Calculate the maximum number of digits we need to
         * fit the number. Overestimate for decimal with log
         * base 8. We need one extra space for signed numbers
         * to store the sign.
         */
        n = (1ULL << (8 * isize)) - 1;
        digits = 0;
        while (n != 0) {
                digits++;
                n >>= (fchar == 'x') ? 4 : 3;
        }
        if (fchar == 'd')
                digits++;
        asprintf(&hdfmt, "%lu/%lu \"%*s%%%s%d%c\" \"\\n\"",
            16UL / (u_long)isize, (u_long)isize, (int)(4 * isize - digits),
            "", (fchar == 'd' || fchar == 'u') ? "" : "0", digits, fchar);
        if (hdfmt == NULL)
                err(1, NULL);
        odadd(hdfmt);
        free(hdfmt);

        return (fmt);
}

static void
odadd(const char *fmt)
{
        static int needpad;

        if (needpad)
                add("\""PADDING"\"");
        add(fmt);
        needpad = 1;
}