cmd/mandoc/mandoc.c

	mandoc.c revision 260e9a87725c090ba5835b1f9f0b62fa2f96036f
/*  $Id: mandoc.c,v 1.92 2015/02/20 23:55:10 schwarze Exp $ */
/*
 * Copyright (c) 2008-2011, 2014 Kristaps Dzonsons <kristaps@bsd.lv>
 * Copyright (c) 2011-2015 Ingo Schwarze <schwarze@openbsd.org>
 *
 * 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.
 */
#include "config.h"

#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.h"
#include "mandoc_aux.h"
#include "libmandoc.h"

#define DATESIZE 32

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


enum mandoc_esc
mandoc_escape(const char **end, const char **start, int *sz)
{
    const char  *local_start;
    int      local_sz;
    char         term;
    enum mandoc_esc  gly;

    /*
     * When the caller doesn't provide return storage,
     * use local storage.
     */

    if (NULL == start)
        start = &local_start;
    if (NULL == sz)
        sz = &local_sz;

    /*
     * Beyond the backslash, at least one input character
     * is part of the escape sequence.  With one exception
     * (see below), that character won't be returned.
     */

    gly = ESCAPE_ERROR;
    *start = ++*end;
    *sz = 0;
    term = '\0';

    switch ((*start)[-1]) {
    /*
     * First the glyphs.  There are several different forms of
     * these, but each eventually returns a substring of the glyph
     * name.
     */
    case '(':
        gly = ESCAPE_SPECIAL;
        *sz = 2;
        break;
    case '[':
        gly = ESCAPE_SPECIAL;
        term = ']';
        break;
    case 'C':
        if ('\'' != **start)
            return(ESCAPE_ERROR);
        *start = ++*end;
        gly = ESCAPE_SPECIAL;
        term = '\'';
        break;

    /*
     * Escapes taking no arguments at all.
     */
    case 'd':
        /* FALLTHROUGH */
    case 'u':
        return(ESCAPE_IGNORE);

    /*
     * The \z escape is supposed to output the following
     * character without advancing the cursor position.
     * Since we are mostly dealing with terminal mode,
     * let us just skip the next character.
     */
    case 'z':
        return(ESCAPE_SKIPCHAR);

    /*
     * Handle all triggers matching \X(xy, \Xx, and \X[xxxx], where
     * 'X' is the trigger.  These have opaque sub-strings.
     */
    case 'F':
        /* FALLTHROUGH */
    case 'g':
        /* FALLTHROUGH */
    case 'k':
        /* FALLTHROUGH */
    case 'M':
        /* FALLTHROUGH */
    case 'm':
        /* FALLTHROUGH */
    case 'n':
        /* FALLTHROUGH */
    case 'V':
        /* FALLTHROUGH */
    case 'Y':
        gly = ESCAPE_IGNORE;
        /* FALLTHROUGH */
    case 'f':
        if (ESCAPE_ERROR == gly)
            gly = ESCAPE_FONT;
        switch (**start) {
        case '(':
            *start = ++*end;
            *sz = 2;
            break;
        case '[':
            *start = ++*end;
            term = ']';
            break;
        default:
            *sz = 1;
            break;
        }
        break;

    /*
     * These escapes are of the form \X'Y', where 'X' is the trigger
     * and 'Y' is any string.  These have opaque sub-strings.
     * The \B and \w escapes are handled in roff.c, roff_res().
     */
    case 'A':
        /* FALLTHROUGH */
    case 'b':
        /* FALLTHROUGH */
    case 'D':
        /* FALLTHROUGH */
    case 'R':
        /* FALLTHROUGH */
    case 'X':
        /* FALLTHROUGH */
    case 'Z':
        gly = ESCAPE_IGNORE;
        /* FALLTHROUGH */
    case 'o':
        if (**start == '\0')
            return(ESCAPE_ERROR);
        if (gly == ESCAPE_ERROR)
            gly = ESCAPE_OVERSTRIKE;
        term = **start;
        *start = ++*end;
        break;

    /*
     * These escapes are of the form \X'N', where 'X' is the trigger
     * and 'N' resolves to a numerical expression.
     */
    case 'h':
        /* FALLTHROUGH */
    case 'H':
        /* FALLTHROUGH */
    case 'L':
        /* FALLTHROUGH */
    case 'l':
        /* FALLTHROUGH */
    case 'S':
        /* FALLTHROUGH */
    case 'v':
        /* FALLTHROUGH */
    case 'x':
        if (strchr(" %&()*+-./0123456789:<=>", **start)) {
            if ('\0' != **start)
                ++*end;
            return(ESCAPE_ERROR);
        }
        gly = ESCAPE_IGNORE;
        term = **start;
        *start = ++*end;
        break;

    /*
     * Special handling for the numbered character escape.
     * XXX Do any other escapes need similar handling?
     */
    case 'N':
        if ('\0' == **start)
            return(ESCAPE_ERROR);
        (*end)++;
        if (isdigit((unsigned char)**start)) {
            *sz = 1;
            return(ESCAPE_IGNORE);
        }
        (*start)++;
        while (isdigit((unsigned char)**end))
            (*end)++;
        *sz = *end - *start;
        if ('\0' != **end)
            (*end)++;
        return(ESCAPE_NUMBERED);

    /*
     * Sizes get a special category of their own.
     */
    case 's':
        gly = ESCAPE_IGNORE;

        /* See +/- counts as a sign. */
        if ('+' == **end || '-' == **end || ASCII_HYPH == **end)
            *start = ++*end;

        switch (**end) {
        case '(':
            *start = ++*end;
            *sz = 2;
            break;
        case '[':
            *start = ++*end;
            term = ']';
            break;
        case '\'':
            *start = ++*end;
            term = '\'';
            break;
        case '3':
            /* FALLTHROUGH */
        case '2':
            /* FALLTHROUGH */
        case '1':
            *sz = (*end)[-1] == 's' &&
                isdigit((unsigned char)(*end)[1]) ? 2 : 1;
            break;
        default:
            *sz = 1;
            break;
        }

        break;

    /*
     * Anything else is assumed to be a glyph.
     * In this case, pass back the character after the backslash.
     */
    default:
        gly = ESCAPE_SPECIAL;
        *start = --*end;
        *sz = 1;
        break;
    }

    assert(ESCAPE_ERROR != gly);

    /*
     * Read up to the terminating character,
     * paying attention to nested escapes.
     */

    if ('\0' != term) {
        while (**end != term) {
            switch (**end) {
            case '\0':
                return(ESCAPE_ERROR);
            case '\\':
                (*end)++;
                if (ESCAPE_ERROR ==
                    mandoc_escape(end, NULL, NULL))
                    return(ESCAPE_ERROR);
                break;
            default:
                (*end)++;
                break;
            }
        }
        *sz = (*end)++ - *start;
    } else {
        assert(*sz > 0);
        if ((size_t)*sz > strlen(*start))
            return(ESCAPE_ERROR);
        *end += *sz;
    }

    /* Run post-processors. */

    switch (gly) {
    case ESCAPE_FONT:
        if (2 == *sz) {
            if ('C' == **start) {
                /*
                 * Treat constant-width font modes
                 * just like regular font modes.
                 */
                (*start)++;
                (*sz)--;
            } else {
                if ('B' == (*start)[0] && 'I' == (*start)[1])
                    gly = ESCAPE_FONTBI;
                break;
            }
        } else if (1 != *sz)
            break;

        switch (**start) {
        case '3':
            /* FALLTHROUGH */
        case 'B':
            gly = ESCAPE_FONTBOLD;
            break;
        case '2':
            /* FALLTHROUGH */
        case 'I':
            gly = ESCAPE_FONTITALIC;
            break;
        case 'P':
            gly = ESCAPE_FONTPREV;
            break;
        case '1':
            /* FALLTHROUGH */
        case 'R':
            gly = ESCAPE_FONTROMAN;
            break;
        }
        break;
    case ESCAPE_SPECIAL:
        if (1 == *sz && 'c' == **start)
            gly = ESCAPE_NOSPACE;
        /*
         * Unicode escapes are defined in groff as \[u0000]
         * to \[u10FFFF], where the contained value must be
         * a valid Unicode codepoint.  Here, however, only
         * check the length and range.
         */
        if (**start != 'u' || *sz < 5 || *sz > 7)
            break;
        if (*sz == 7 && ((*start)[1] != '1' || (*start)[2] != '0'))
            break;
        if (*sz == 6 && (*start)[1] == '0')
            break;
        if ((int)strspn(*start + 1, "0123456789ABCDEFabcdef")
            + 1 == *sz)
            gly = ESCAPE_UNICODE;
        break;
    default:
        break;
    }

    return(gly);
}

/*
 * Parse a quoted or unquoted roff-style request or macro argument.
 * Return a pointer to the parsed argument, which is either the original
 * pointer or advanced by one byte in case the argument is quoted.
 * NUL-terminate the argument in place.
 * Collapse pairs of quotes inside quoted arguments.
 * Advance the argument pointer to the next argument,
 * or to the NUL byte terminating the argument line.
 */
char *
mandoc_getarg(struct mparse *parse, char **cpp, int ln, int *pos)
{
    char     *start, *cp;
    int   quoted, pairs, white;

    /* Quoting can only start with a new word. */
    start = *cpp;
    quoted = 0;
    if ('"' == *start) {
        quoted = 1;
        start++;
    }

    pairs = 0;
    white = 0;
    for (cp = start; '\0' != *cp; cp++) {

        /*
         * Move the following text left
         * after quoted quotes and after "\\" and "\t".
         */
        if (pairs)
            cp[-pairs] = cp[0];

        if ('\\' == cp[0]) {
            /*
             * In copy mode, translate double to single
             * backslashes and backslash-t to literal tabs.
             */
            switch (cp[1]) {
            case 't':
                cp[0] = '\t';
                /* FALLTHROUGH */
            case '\\':
                pairs++;
                cp++;
                break;
            case ' ':
                /* Skip escaped blanks. */
                if (0 == quoted)
                    cp++;
                break;
            default:
                break;
            }
        } else if (0 == quoted) {
            if (' ' == cp[0]) {
                /* Unescaped blanks end unquoted args. */
                white = 1;
                break;
            }
        } else if ('"' == cp[0]) {
            if ('"' == cp[1]) {
                /* Quoted quotes collapse. */
                pairs++;
                cp++;
            } else {
                /* Unquoted quotes end quoted args. */
                quoted = 2;
                break;
            }
        }
    }

    /* Quoted argument without a closing quote. */
    if (1 == quoted)
        mandoc_msg(MANDOCERR_ARG_QUOTE, parse, ln, *pos, NULL);

    /* NUL-terminate this argument and move to the next one. */
    if (pairs)
        cp[-pairs] = '\0';
    if ('\0' != *cp) {
        *cp++ = '\0';
        while (' ' == *cp)
            cp++;
    }
    *pos += (int)(cp - start) + (quoted ? 1 : 0);
    *cpp = cp;

    if ('\0' == *cp && (white || ' ' == cp[-1]))
        mandoc_msg(MANDOCERR_SPACE_EOL, parse, ln, *pos, NULL);

    return(start);
}

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

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

    pp = NULL;
#if HAVE_STRPTIME
    pp = strptime(p, fmt, &tm);
#endif
    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;

    tm = localtime(&t);
    if (tm == NULL)
        return(NULL);

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

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

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

fail:
    free(buf);
    return(NULL);
}

char *
mandoc_normdate(struct mparse *parse, char *in, int ln, int pos)
{
    char        *out;
    time_t       t;

    if (NULL == in || '\0' == *in ||
        0 == strcmp(in, "$" "Mdocdate$")) {
        mandoc_msg(MANDOCERR_DATE_MISSING, parse, ln, pos, NULL);
        time(&t);
    }
    else if (a2time(&t, "%Y-%m-%d", in))
        t = 0;
    else if (!a2time(&t, "$" "Mdocdate: %b %d %Y $", in) &&
        !a2time(&t, "%b %d, %Y", in)) {
        mandoc_msg(MANDOCERR_DATE_BAD, parse, ln, pos, in);
        t = 0;
    }
    out = t ? time2a(t) : NULL;
    return(out ? out : mandoc_strdup(in));
}

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 '\"':
            /* FALLTHROUGH */
        case '\'':
            /* FALLTHROUGH */
        case ']':
            /* FALLTHROUGH */
        case ')':
            if (0 == found)
                enclosed = 1;
            break;
        case '.':
            /* FALLTHROUGH */
        case '!':
            /* FALLTHROUGH */
        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);
}