/* $OpenBSD: mandoc.c,v 1.89 2022/05/19 15:17:50 schwarze Exp $ */
/*
 * Copyright (c) 2010, 2011, 2015, 2017, 2018, 2019, 2020, 2021
 *               Ingo Schwarze <schwarze@openbsd.org>
 * Copyright (c) 2009, 2010 Kristaps Dzonsons <kristaps@bsd.lv>
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHORS DISCLAIM ALL WARRANTIES
 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR
 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 *
 * Utility functions to handle end of sentence punctuation
 * and dates and times, for use by mdoc(7) and man(7) parsers.
 * Utility functions to handle fonts and numbers,
 * for use by mandoc(1) parsers and formatters.
 */
#include <sys/types.h>

#include <assert.h>
#include <ctype.h>
#include <errno.h>
#include <limits.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <time.h>

#include "mandoc_aux.h"
#include "mandoc.h"
#include "roff.h"
#include "libmandoc.h"
#include "roff_int.h"

static  int      a2time(time_t *, const char *, const char *);
static  char    *time2a(time_t);


enum mandoc_esc
mandoc_font(const char *cp, int sz)
{
        switch (sz) {
        case 0:
                return ESCAPE_FONTPREV;
        case 1:
                switch (cp[0]) {
                case 'B':
                case '3':
                        return ESCAPE_FONTBOLD;
                case 'I':
                case '2':
                        return ESCAPE_FONTITALIC;
                case 'P':
                        return ESCAPE_FONTPREV;
                case 'R':
                case '1':
                        return ESCAPE_FONTROMAN;
                case '4':
                        return ESCAPE_FONTBI;
                default:
                        return ESCAPE_ERROR;
                }
        case 2:
                switch (cp[0]) {
                case 'B':
                        switch (cp[1]) {
                        case 'I':
                                return ESCAPE_FONTBI;
                        default:
                                return ESCAPE_ERROR;
                        }
                case 'C':
                        switch (cp[1]) {
                        case 'B':
                                return ESCAPE_FONTCB;
                        case 'I':
                                return ESCAPE_FONTCI;
                        case 'R':
                        case 'W':
                                return ESCAPE_FONTCR;
                        default:
                                return ESCAPE_ERROR;
                        }
                default:
                        return ESCAPE_ERROR;
                }
        default:
                return ESCAPE_ERROR;
        }
}

static int
a2time(time_t *t, const char *fmt, const char *p)
{
        struct tm        tm;
        char            *pp;

        memset(&tm, 0, sizeof(struct tm));

        pp = strptime(p, fmt, &tm);
        if (NULL != pp && '\0' == *pp) {
                *t = mktime(&tm);
                return 1;
        }

        return 0;
}

static char *
time2a(time_t t)
{
        struct tm       *tm;
        char            *buf, *p;
        size_t           ssz;
        int              isz;

        buf = NULL;
        tm = localtime(&t);
        if (tm == NULL)
                goto fail;

        /*
         * Reserve space:
         * up to 9 characters for the month (September) + blank
         * up to 2 characters for the day + comma + blank
         * 4 characters for the year and a terminating '\0'
         */

        p = buf = mandoc_malloc(10 + 4 + 4 + 1);

        if ((ssz = strftime(p, 10 + 1, "%B ", tm)) == 0)
                goto fail;
        p += (int)ssz;

        /*
         * The output format is just "%d" here, not "%2d" or "%02d".
         * That's also the reason why we can't just format the
         * date as a whole with "%B %e, %Y" or "%B %d, %Y".
         * Besides, the present approach is less prone to buffer
         * overflows, in case anybody should ever introduce the bug
         * of looking at LC_TIME.
         */

        isz = snprintf(p, 4 + 1, "%d, ", tm->tm_mday);
        if (isz < 0 || isz > 4)
                goto fail;
        p += isz;

        if (strftime(p, 4 + 1, "%Y", tm) == 0)
                goto fail;
        return buf;

fail:
        free(buf);
        return mandoc_strdup("");
}

char *
mandoc_normdate(struct roff_node *nch, struct roff_node *nbl)
{
        char            *cp;
        time_t           t;

        /* No date specified. */

        if (nch == NULL) {
                if (nbl == NULL)
                        mandoc_msg(MANDOCERR_DATE_MISSING, 0, 0, NULL);
                else
                        mandoc_msg(MANDOCERR_DATE_MISSING, nbl->line,
                            nbl->pos, "%s", roff_name[nbl->tok]);
                return mandoc_strdup("");
        }
        if (*nch->string == '\0') {
                mandoc_msg(MANDOCERR_DATE_MISSING, nch->line,
                    nch->pos, "%s", roff_name[nbl->tok]);
                return mandoc_strdup("");
        }
        if (strcmp(nch->string, "$" "Mdocdate$") == 0)
                return time2a(time(NULL));

        /* Valid mdoc(7) date format. */

        if (a2time(&t, "$" "Mdocdate: %b %d %Y $", nch->string) ||
            a2time(&t, "%b %d, %Y", nch->string)) {
                cp = time2a(t);
                if (t > time(NULL) + 86400)
                        mandoc_msg(MANDOCERR_DATE_FUTURE, nch->line,
                            nch->pos, "%s %s", roff_name[nbl->tok], cp);
                else if (*nch->string != '$' &&
                    strcmp(nch->string, cp) != 0)
                        mandoc_msg(MANDOCERR_DATE_NORM, nch->line,
                            nch->pos, "%s %s", roff_name[nbl->tok], cp);
                return cp;
        }

        /* In man(7), do not warn about the legacy format. */

        if (a2time(&t, "%Y-%m-%d", nch->string) == 0)
                mandoc_msg(MANDOCERR_DATE_BAD, nch->line, nch->pos,
                    "%s %s", roff_name[nbl->tok], nch->string);
        else if (t > time(NULL) + 86400)
                mandoc_msg(MANDOCERR_DATE_FUTURE, nch->line, nch->pos,
                    "%s %s", roff_name[nbl->tok], nch->string);
        else if (nbl->tok == MDOC_Dd)
                mandoc_msg(MANDOCERR_DATE_LEGACY, nch->line, nch->pos,
                    "Dd %s", nch->string);

        /* Use any non-mdoc(7) date verbatim. */

        return mandoc_strdup(nch->string);
}

int
mandoc_eos(const char *p, size_t sz)
{
        const char      *q;
        int              enclosed, found;

        if (0 == sz)
                return 0;

        /*
         * End-of-sentence recognition must include situations where
         * some symbols, such as `)', allow prior EOS punctuation to
         * propagate outward.
         */

        enclosed = found = 0;
        for (q = p + (int)sz - 1; q >= p; q--) {
                switch (*q) {
                case '\"':
                case '\'':
                case ']':
                case ')':
                        if (0 == found)
                                enclosed = 1;
                        break;
                case '.':
                case '!':
                case '?':
                        found = 1;
                        break;
                default:
                        return found &&
                            (!enclosed || isalnum((unsigned char)*q));
                }
        }

        return found && !enclosed;
}

/*
 * Convert a string to a long that may not be <0.
 * If the string is invalid, or is less than 0, return -1.
 */
int
mandoc_strntoi(const char *p, size_t sz, int base)
{
        char             buf[32];
        char            *ep;
        long             v;

        if (sz > 31)
                return -1;

        memcpy(buf, p, sz);
        buf[(int)sz] = '\0';

        errno = 0;
        v = strtol(buf, &ep, base);

        if (buf[0] == '\0' || *ep != '\0')
                return -1;

        if (v > INT_MAX)
                v = INT_MAX;
        if (v < INT_MIN)
                v = INT_MIN;

        return (int)v;
}