xref: /openbsd-src/gnu/usr.bin/perl/vutil.c (revision e0a5400065cea17a7de6532c2ecb091c5f17622b)

/* This file is part of the "version" CPAN distribution.  Please avoid
   editing it in the perl core. */

#ifdef PERL_CORE
#  include "vutil.h"
#endif

#define VERSION_MAX 0x7FFFFFFF

#ifndef STRLENs
#  define STRLENs(s)  (sizeof("" s "") - 1)
#endif
#ifndef POSIX_SETLOCALE_LOCK
#  ifdef gwLOCALE_LOCK
#    define POSIX_SETLOCALE_LOCK    gwLOCALE_LOCK
#    define POSIX_SETLOCALE_UNLOCK  gwLOCALE_UNLOCK
#  else
#    define POSIX_SETLOCALE_LOCK    NOOP
#    define POSIX_SETLOCALE_UNLOCK  NOOP
#  endif
#endif
#ifndef DISABLE_LC_NUMERIC_CHANGES
#  ifdef LOCK_LC_NUMERIC_STANDARD
#    define DISABLE_LC_NUMERIC_CHANGES()   LOCK_LC_NUMERIC_STANDARD()
#    define REENABLE_LC_NUMERIC_CHANGES()  UNLOCK_LC_NUMERIC_STANDARD()
#  else
#    define DISABLE_LC_NUMERIC_CHANGES()   NOOP
#    define REENABLE_LC_NUMERIC_CHANGES()  NOOP
#  endif
#endif

/*
=for apidoc prescan_version

Validate that a given string can be parsed as a version object, but doesn't
actually perform the parsing.  Can use either strict or lax validation rules.
Can optionally set a number of hint variables to save the parsing code
some time when tokenizing.

=cut
*/
const char *
#ifdef VUTIL_REPLACE_CORE
Perl_prescan_version2(pTHX_ const char *s, bool strict,
#else
Perl_prescan_version(pTHX_ const char *s, bool strict,
#endif
                     const char **errstr,
                     bool *sqv, int *ssaw_decimal, int *swidth, bool *salpha) {
    bool qv = (sqv ? *sqv : FALSE);
    int width = 3;
    int saw_decimal = 0;
    bool alpha = FALSE;
    const char *d = s;

    PERL_ARGS_ASSERT_PRESCAN_VERSION;
    PERL_UNUSED_CONTEXT;

    if (qv && isDIGIT(*d))
        goto dotted_decimal_version;

    if (*d == 'v') { /* explicit v-string */
        d++;
        if (isDIGIT(*d)) {
            qv = TRUE;
        }
        else { /* degenerate v-string */
            /* requires v1.2.3 */
            BADVERSION(s,errstr,"Invalid version format (dotted-decimal versions require at least three parts)");
        }

dotted_decimal_version:
        if (strict && d[0] == '0' && isDIGIT(d[1])) {
            /* no leading zeros allowed */
            BADVERSION(s,errstr,"Invalid version format (no leading zeros)");
        }

        while (isDIGIT(*d))     /* integer part */
            d++;

        if (*d == '.')
        {
            saw_decimal++;
            d++;                /* decimal point */
        }
        else
        {
            if (strict) {
                /* require v1.2.3 */
                BADVERSION(s,errstr,"Invalid version format (dotted-decimal versions require at least three parts)");
            }
            else {
                goto version_prescan_finish;
            }
        }

        {
            int i = 0;
            int j = 0;
            while (isDIGIT(*d)) {       /* just keep reading */
                i++;
                while (isDIGIT(*d)) {
                    d++; j++;
                    /* maximum 3 digits between decimal */
                    if (strict && j > 3) {
                        BADVERSION(s,errstr,"Invalid version format (maximum 3 digits between decimals)");
                    }
                }
                if (*d == '_') {
                    if (strict) {
                        BADVERSION(s,errstr,"Invalid version format (no underscores)");
                    }
                    if ( alpha ) {
                        BADVERSION(s,errstr,"Invalid version format (multiple underscores)");
                    }
                    d++;
                    alpha = TRUE;
                }
                else if (*d == '.') {
                    if (alpha) {
                        BADVERSION(s,errstr,"Invalid version format (underscores before decimal)");
                    }
                    saw_decimal++;
                    d++;
                }
                else if (!isDIGIT(*d)) {
                    break;
                }
                j = 0;
            }

            if (strict && i < 2) {
                /* requires v1.2.3 */
                BADVERSION(s,errstr,"Invalid version format (dotted-decimal versions require at least three parts)");
            }
        }
    }                                   /* end if dotted-decimal */
    else
    {                                   /* decimal versions */
        int j = 0;                      /* may need this later */
        /* special strict case for leading '.' or '0' */
        if (strict) {
            if (*d == '.') {
                BADVERSION(s,errstr,"Invalid version format (0 before decimal required)");
            }
            if (*d == '0' && isDIGIT(d[1])) {
                BADVERSION(s,errstr,"Invalid version format (no leading zeros)");
            }
        }

        /* and we never support negative versions */
        if ( *d == '-') {
            BADVERSION(s,errstr,"Invalid version format (negative version number)");
        }

        /* consume all of the integer part */
        while (isDIGIT(*d))
            d++;

        /* look for a fractional part */
        if (*d == '.') {
            /* we found it, so consume it */
            saw_decimal++;
            d++;
        }
        else if (!*d || *d == ';' || isSPACE(*d) || *d == '{' || *d == '}') {
            if ( d == s ) {
                /* found nothing */
                BADVERSION(s,errstr,"Invalid version format (version required)");
            }
            /* found just an integer */
            goto version_prescan_finish;
        }
        else if ( d == s ) {
            /* didn't find either integer or period */
            BADVERSION(s,errstr,"Invalid version format (non-numeric data)");
        }
        else if (*d == '_') {
            /* underscore can't come after integer part */
            if (strict) {
                BADVERSION(s,errstr,"Invalid version format (no underscores)");
            }
            else if (isDIGIT(d[1])) {
                BADVERSION(s,errstr,"Invalid version format (alpha without decimal)");
            }
            else {
                BADVERSION(s,errstr,"Invalid version format (misplaced underscore)");
            }
        }
        else {
            /* anything else after integer part is just invalid data */
            BADVERSION(s,errstr,"Invalid version format (non-numeric data)");
        }

        /* scan the fractional part after the decimal point*/

        if (!isDIGIT(*d) && (strict || ! (!*d || *d == ';' || isSPACE(*d) || *d == '{' || *d == '}') )) {
                /* strict or lax-but-not-the-end */
                BADVERSION(s,errstr,"Invalid version format (fractional part required)");
        }

        while (isDIGIT(*d)) {
            d++; j++;
            if (*d == '.' && isDIGIT(d[-1])) {
                if (alpha) {
                    BADVERSION(s,errstr,"Invalid version format (underscores before decimal)");
                }
                if (strict) {
                    BADVERSION(s,errstr,"Invalid version format (dotted-decimal versions must begin with 'v')");
                }
                d = (char *)s;          /* start all over again */
                qv = TRUE;
                goto dotted_decimal_version;
            }
            if (*d == '_') {
                if (strict) {
                    BADVERSION(s,errstr,"Invalid version format (no underscores)");
                }
                if ( alpha ) {
                    BADVERSION(s,errstr,"Invalid version format (multiple underscores)");
                }
                if ( ! isDIGIT(d[1]) ) {
                    BADVERSION(s,errstr,"Invalid version format (misplaced underscore)");
                }
                width = j;
                d++;
                alpha = TRUE;
            }
        }
    }

version_prescan_finish:
    while (isSPACE(*d))
        d++;

    if (!isDIGIT(*d) && (! (!*d || *d == ';' || *d == ':' || *d == '{' || *d == '}') )) {
        /* trailing non-numeric data */
        BADVERSION(s,errstr,"Invalid version format (non-numeric data)");
    }
    if (saw_decimal > 1 && d[-1] == '.') {
        /* no trailing period allowed */
        BADVERSION(s,errstr,"Invalid version format (trailing decimal)");
    }


    if (sqv)
        *sqv = qv;
    if (swidth)
        *swidth = width;
    if (ssaw_decimal)
        *ssaw_decimal = saw_decimal;
    if (salpha)
        *salpha = alpha;
    return d;
}

/*
=for apidoc scan_version

Returns a pointer to the next character after the parsed
version string, as well as upgrading the passed in SV to
an RV.

Function must be called with an already existing SV like

    sv = newSV(0);
    s = scan_version(s, SV *sv, bool qv);

Performs some preprocessing to the string to ensure that
it has the correct characteristics of a version.  Flags the
object if it contains an underscore (which denotes this
is an alpha version).  The boolean qv denotes that the version
should be interpreted as if it had multiple decimals, even if
it doesn't.

=cut
*/

const char *
#ifdef VUTIL_REPLACE_CORE
Perl_scan_version2(pTHX_ const char *s, SV *rv, bool qv)
#else
Perl_scan_version(pTHX_ const char *s, SV *rv, bool qv)
#endif
{
    const char *start = s;
    const char *pos;
    const char *last;
    const char *errstr = NULL;
    int saw_decimal = 0;
    int width = 3;
    bool alpha = FALSE;
    bool vinf = FALSE;
    AV * av;
    SV * hv;

    PERL_ARGS_ASSERT_SCAN_VERSION;

    while (isSPACE(*s)) /* leading whitespace is OK */
        s++;

    last = PRESCAN_VERSION(s, FALSE, &errstr, &qv, &saw_decimal, &width, &alpha);
    if (errstr) {
        /* "undef" is a special case and not an error */
        if ( ! ( *s == 'u' && strEQ(s+1,"ndef")) ) {
            Perl_croak(aTHX_ "%s", errstr);
        }
    }

    start = s;
    if (*s == 'v')
        s++;
    pos = s;

    /* Now that we are through the prescan, start creating the object */
    av = newAV();
    hv = newSVrv(rv, "version"); /* create an SV and upgrade the RV */
    (void)sv_upgrade(hv, SVt_PVHV); /* needs to be an HV type */

#ifndef NODEFAULT_SHAREKEYS
    HvSHAREKEYS_on(hv);         /* key-sharing on by default */
#endif

    if ( qv )
        (void)hv_stores(MUTABLE_HV(hv), "qv", newSViv(qv));
    if ( alpha )
        (void)hv_stores(MUTABLE_HV(hv), "alpha", newSViv(alpha));
    if ( !qv && width < 3 )
        (void)hv_stores(MUTABLE_HV(hv), "width", newSViv(width));

    while (isDIGIT(*pos) || *pos == '_')
        pos++;
    if (!isALPHA(*pos)) {
        I32 rev;

        for (;;) {
            rev = 0;
            {
                /* this is atoi() that delimits on underscores */
                const char *end = pos;
                I32 mult = 1;
                I32 orev;

                /* the following if() will only be true after the decimal
                 * point of a version originally created with a bare
                 * floating point number, i.e. not quoted in any way
                 */
                if ( !qv && s > start && saw_decimal == 1 ) {
                    mult *= 100;
                    while ( s < end ) {
                        if (*s == '_')
                            continue;
                        orev = rev;
                        rev += (*s - '0') * mult;
                        mult /= 10;
                        if (   (PERL_ABS(orev) > PERL_ABS(rev))
                            || (PERL_ABS(rev) > VERSION_MAX )) {
                            Perl_ck_warner(aTHX_ packWARN(WARN_OVERFLOW),
                                           "Integer overflow in version %d",VERSION_MAX);
                            s = end - 1;
                            rev = VERSION_MAX;
                            vinf = 1;
                        }
                        s++;
                        if ( *s == '_' )
                            s++;
                    }
                }
                else {
                    while (--end >= s) {
                        int i;
                        if (*end == '_')
                            continue;
                        i = (*end - '0');
                        if (   (mult == VERSION_MAX)
                            || (i > VERSION_MAX / mult)
                            || (i * mult > VERSION_MAX - rev))
                        {
                            Perl_ck_warner(aTHX_ packWARN(WARN_OVERFLOW),
                                           "Integer overflow in version");
                            end = s - 1;
                            rev = VERSION_MAX;
                            vinf = 1;
                        }
                        else
                            rev += i * mult;

                        if (mult > VERSION_MAX / 10)
                            mult = VERSION_MAX;
                        else
                            mult *= 10;
                    }
                }
            }

            /* Append revision */
            av_push(av, newSViv(rev));
            if ( vinf ) {
                s = last;
                break;
            }
            else if ( *pos == '.' ) {
                pos++;
                if (qv) {
                    while (*pos == '0')
                        ++pos;
                }
                s = pos;
            }
            else if ( *pos == '_' && isDIGIT(pos[1]) )
                s = ++pos;
            else if ( *pos == ',' && isDIGIT(pos[1]) )
                s = ++pos;
            else if ( isDIGIT(*pos) )
                s = pos;
            else {
                s = pos;
                break;
            }
            if ( qv ) {
                while ( isDIGIT(*pos) || *pos == '_')
                    pos++;
            }
            else {
                int digits = 0;
                while ( ( isDIGIT(*pos) || *pos == '_' ) && digits < 3 ) {
                    if ( *pos != '_' )
                        digits++;
                    pos++;
                }
            }
        }
    }
    if ( qv ) { /* quoted versions always get at least three terms*/
        SSize_t len = AvFILLp(av);
        /* This for loop appears to trigger a compiler bug on OS X, as it
           loops infinitely. Yes, len is negative. No, it makes no sense.
           Compiler in question is:
           gcc version 3.3 20030304 (Apple Computer, Inc. build 1640)
           for ( len = 2 - len; len > 0; len-- )
           av_push(MUTABLE_AV(sv), newSViv(0));
        */
        len = 2 - len;
        while (len-- > 0)
            av_push(av, newSViv(0));
    }

    /* need to save off the current version string for later */
    if ( vinf ) {
        SV * orig = newSVpvn("v.Inf", sizeof("v.Inf")-1);
        (void)hv_stores(MUTABLE_HV(hv), "original", orig);
        (void)hv_stores(MUTABLE_HV(hv), "vinf", newSViv(1));
    }
    else if ( s > start ) {
        SV * orig = newSVpvn(start,s-start);
        if ( qv && saw_decimal == 1 && *start != 'v' ) {
            /* need to insert a v to be consistent */
            sv_insert(orig, 0, 0, "v", 1);
        }
        (void)hv_stores(MUTABLE_HV(hv), "original", orig);
    }
    else {
        (void)hv_stores(MUTABLE_HV(hv), "original", newSVpvs("0"));
        av_push(av, newSViv(0));
    }

    /* And finally, store the AV in the hash */
    (void)hv_stores(MUTABLE_HV(hv), "version", newRV_noinc(MUTABLE_SV(av)));

    /* fix RT#19517 - special case 'undef' as string */
    if ( *s == 'u' && strEQ(s+1,"ndef") ) {
        s += 5;
    }

    return s;
}

/*
=for apidoc new_version

Returns a new version object based on the passed in SV:

    SV *sv = new_version(SV *ver);

Does not alter the passed in ver SV.  See "upg_version" if you
want to upgrade the SV.

=cut
*/

SV *
#ifdef VUTIL_REPLACE_CORE
Perl_new_version2(pTHX_ SV *ver)
#else
Perl_new_version(pTHX_ SV *ver)
#endif
{
    SV * const rv = newSV(0);
    PERL_ARGS_ASSERT_NEW_VERSION;
    if ( ISA_VERSION_OBJ(ver) ) /* can just copy directly */
    {
        SSize_t key;
        AV * const av = newAV();
        AV *sav;
        /* This will get reblessed later if a derived class*/
        SV * const hv = newSVrv(rv, "version");
        (void)sv_upgrade(hv, SVt_PVHV); /* needs to be an HV type */
#ifndef NODEFAULT_SHAREKEYS
        HvSHAREKEYS_on(hv);         /* key-sharing on by default */
#endif

        if ( SvROK(ver) )
            ver = SvRV(ver);

        /* Begin copying all of the elements */
        if ( hv_exists(MUTABLE_HV(ver), "qv", 2) )
            (void)hv_stores(MUTABLE_HV(hv), "qv", newSViv(1));

        if ( hv_exists(MUTABLE_HV(ver), "alpha", 5) )
            (void)hv_stores(MUTABLE_HV(hv), "alpha", newSViv(1));
        {
            SV ** svp = hv_fetchs(MUTABLE_HV(ver), "width", FALSE);
            if(svp) {
                const I32 width = SvIV(*svp);
                (void)hv_stores(MUTABLE_HV(hv), "width", newSViv(width));
            }
        }
        {
            SV ** svp = hv_fetchs(MUTABLE_HV(ver), "original", FALSE);
            if(svp)
                (void)hv_stores(MUTABLE_HV(hv), "original", newSVsv(*svp));
        }
        sav = MUTABLE_AV(SvRV(*hv_fetchs(MUTABLE_HV(ver), "version", FALSE)));
        /* This will get reblessed later if a derived class*/
        for ( key = 0; key <= av_len(sav); key++ )
        {
            SV * const sv = *av_fetch(sav, key, FALSE);
            const I32 rev = SvIV(sv);
            av_push(av, newSViv(rev));
        }

        (void)hv_stores(MUTABLE_HV(hv), "version", newRV_noinc(MUTABLE_SV(av)));
        return rv;
    }
#ifdef SvVOK
    {
        const MAGIC* const mg = SvVSTRING_mg(ver);
        if ( mg ) { /* already a v-string */
            const STRLEN len = mg->mg_len;
            const char * const version = (const char*)mg->mg_ptr;
            char *raw, *under;
            static const char underscore[] = "_";
            sv_setpvn(rv,version,len);
            raw = SvPV_nolen(rv);
            under = ninstr(raw, raw+len, underscore, underscore + 1);
            if (under) {
                Move(under + 1, under, raw + len - under - 1, char);
                SvCUR_set(rv, SvCUR(rv) - 1);
                *SvEND(rv) = '\0';
            }
            /* this is for consistency with the pure Perl class */
            if ( isDIGIT(*version) )
                sv_insert(rv, 0, 0, "v", 1);
        }
        else {
#endif
        SvSetSV_nosteal(rv, ver); /* make a duplicate */
#ifdef SvVOK
        }
    }
#endif
    sv_2mortal(rv); /* in case upg_version croaks before it returns */
    return SvREFCNT_inc_NN(UPG_VERSION(rv, FALSE));
}

/*
=for apidoc upg_version

In-place upgrade of the supplied SV to a version object.

    SV *sv = upg_version(SV *sv, bool qv);

Returns a pointer to the upgraded SV.  Set the boolean qv if you want
to force this SV to be interpreted as an "extended" version.

=cut
*/

/* Macro to do the meat of getting the PV of an NV version number.  This is
 * macroized because can be called from several places */
#define GET_NUMERIC_VERSION(ver, sv, tbuf, buf, len)                        \
    STMT_START {                                                            \
                                                                            \
        /* Prevent callees from trying to change the locale */              \
        DISABLE_LC_NUMERIC_CHANGES();                                       \
                                                                            \
        /* We earlier created 'sv' for very large version numbers, to rely  \
         * on the specialized algorithms SV code has built-in for such      \
         * values */                                                        \
        if (sv) {                                                           \
            Perl_sv_setpvf(aTHX_ sv, "%.9" NVff, SvNVX(ver));               \
            len = SvCUR(sv);                                                \
            buf = SvPVX(sv);                                                \
        }                                                                   \
        else {                                                              \
            len = my_snprintf(tbuf, sizeof(tbuf), "%.9" NVff, SvNVX(ver));  \
            buf = tbuf;                                                     \
        }                                                                   \
                                                                            \
        REENABLE_LC_NUMERIC_CHANGES();                                      \
    } STMT_END

SV *
#ifdef VUTIL_REPLACE_CORE
Perl_upg_version2(pTHX_ SV *ver, bool qv)
#else
Perl_upg_version(pTHX_ SV *ver, bool qv)
#endif
{
    const char *version, *s;
#ifdef SvVOK
    const MAGIC *mg;
#endif

#if PERL_VERSION_LT(5,19,8) && defined(USE_ITHREADS)
    ENTER;
#endif
    PERL_ARGS_ASSERT_UPG_VERSION;

    if ( (SvUOK(ver) && SvUVX(ver) > VERSION_MAX)
        || (SvIOK(ver) && SvIVX(ver) > VERSION_MAX) )
    {
        /* out of bounds [unsigned] integer */
        STRLEN len;
        char tbuf[64];
        len = my_snprintf(tbuf, sizeof(tbuf), "%d", VERSION_MAX);
        version = savepvn(tbuf, len);
        SAVEFREEPV(version);
        Perl_ck_warner(aTHX_ packWARN(WARN_OVERFLOW),
                       "Integer overflow in version %d",VERSION_MAX);
    }
    else if ( SvUOK(ver) || SvIOK(ver))
#if PERL_VERSION_LT(5,17,2)
VER_IV:
#endif
    {
        version = savesvpv(ver);
        SAVEFREEPV(version);
    }
    else if (SvNOK(ver) && !( SvPOK(ver) && SvCUR(ver) == 3 ) )
#if PERL_VERSION_LT(5,17,2)
VER_NV:
#endif
    {
        STRLEN len;

        /* may get too much accuracy */
        char tbuf[64];
#ifdef __vax__
	SV *sv = SvNVX(ver) > 10e37 ? newSV(64) : 0;
#else
        SV *sv = SvNVX(ver) > 10e50 ? newSV(64) : 0;
#endif
        char *buf;

#if PERL_VERSION_GE(5,19,0)
        if (SvPOK(ver)) {
            /* dualvar? */
            goto VER_PV;
        }
#endif

        {

#ifdef USE_POSIX_2008_LOCALE

            /* With POSIX 2008, all we have to do is toggle to the C locale
             * just long enough to get the value (which should have a dot). */
            const locale_t locale_obj_on_entry = uselocale(PL_C_locale_obj);
            GET_NUMERIC_VERSION(ver, sv, tbuf, buf, len);
            uselocale(locale_obj_on_entry);
#else
            /* Without POSIX 2008, it could be that toggling will zap another
            * thread's locale.  Avoid that if possible by looking at the NV and
            * changing a non-dot radix into a dot */

            char * radix = NULL;
            unsigned int radix_len = 0;

            GET_NUMERIC_VERSION(ver, sv, tbuf, buf, len);

#  ifndef ARABIC_DECIMAL_SEPARATOR_UTF8

            /* This becomes feasible since there are only very few possible
             * radix characters in the world.  khw knows of just 3 possible
             * ones.  If we are being compiled on a perl without the very rare
             * third one, ARABIC DECIMAL SEPARATOR,  just scan for the other
             * two: FULL STOP (dot) and COMMA */
            radix = strpbrk(buf, ".,");
            if (LIKELY(radix)) {
                radix_len = 1;
            }
#  else
            /* Here, we have information about the third one; since it is
             * multi-byte, it becomes a little more work.  Scan for the dot,
             * comma, or first byte of the arabic one */
            radix = strpbrk(buf,
                            ".,"
                            ARABIC_DECIMAL_SEPARATOR_UTF8_FIRST_BYTE_s);

            if (LIKELY(radix)) {
                if (LIKELY(   (* (U8 *) radix)
                           != ARABIC_DECIMAL_SEPARATOR_UTF8_FIRST_BYTE))
                {
                    radix_len = 1;  /* Dot and comma are length 1 */
                }
                else {

                    /* Make sure that the rest of the bytes are what we expect
                     * for the remainder of the arabic radix.  If not, we
                     * didn't find the radix. */
                    radix_len = STRLENs(ARABIC_DECIMAL_SEPARATOR_UTF8);
                    if (   radix + radix_len >= buf + len
                        || memNEs(radix + 1,
                                STRLENs(ARABIC_DECIMAL_SEPARATOR_UTF8_TAIL),
                                ARABIC_DECIMAL_SEPARATOR_UTF8_TAIL))
                    {
                        radix = NULL;
                        radix_len = 0;
                    }
                }
            }

#  endif

            /* Now convert any found radix into a dot (if not already).  This
            * effectively does:  ver =~ s/radix/dot/   */
            if (radix) {
                if (*radix != '.') {
                    *radix = '.';

                    if (radix_len > 1) {
                        Move(radix + radix_len,  /* from what follows the radix
                                                  */
                            radix + 1,          /* to just after the new dot */

                                /* the number of bytes remaining, plus the NUL
                                 * */
                            len - (radix - buf) - radix_len + 1,
                            char);
                        len -= radix_len - 1;
                    }
                }

                /* Guard against the very unlikely case that the radix is more
                 * than a single character, like ".."; that is, make sure the
                 * radix string we found above is the whole radix, and not just
                 * the prefix of a longer one.   Success is indicated by it
                 * being at the end of the string, or the next byte should be a
                 * digit */
                if (radix < buf + len && ! inRANGE(radix[1], '0', '9')) {
                    radix = NULL;
                    radix_len = 0;
                }
            }

            if (! radix) {

                /* If we couldn't find what the radix is, or didn't find it in
                 * the PV, resort to toggling the locale to one known to have a
                 * dot radix.  This may or may not be called from code that has
                 * switched locales without letting perl know, therefore we
                 * have to find it from first principals.  See [perl #121930].
                 * */

#  if ! defined(LC_NUMERIC) || ! defined(USE_LOCALE_NUMERIC)

                Perl_croak(aTHX_ "panic: Unexpectedly didn't find a dot radix"
                                 " character in '%s'", buf);
#  else
                const char * locale_name_on_entry = NULL;

                /* In windows, or not threaded, or not thread-safe, if it isn't
                 * C, set it to C. */

                POSIX_SETLOCALE_LOCK;    /* Start critical section */

                locale_name_on_entry = setlocale(LC_NUMERIC, NULL);
                if (   strEQ(locale_name_on_entry, "C")
                    || strEQ(locale_name_on_entry, "C.UTF-8")
                    || strEQ(locale_name_on_entry, "POSIX"))
                {
                    /* No need to change the locale, since these all are known
                     * to have a dot radix.  Change the variable to indicate to
                     * the restore code that nothing needs to be done */
                    locale_name_on_entry = NULL;
                }
                else {
                    /* The setlocale() call might free or overwrite the name */
                    locale_name_on_entry = savepv(locale_name_on_entry);
                    setlocale(LC_NUMERIC, "C");
                }

                GET_NUMERIC_VERSION(ver, sv, tbuf, buf, len);

                if (locale_name_on_entry) {
                    setlocale(LC_NUMERIC, locale_name_on_entry);
                    Safefree(locale_name_on_entry);
                }

                POSIX_SETLOCALE_UNLOCK;  /* End critical section */
#  endif
            }
#endif
        }

        /* Strip trailing zero's from the version number */
        while (buf[len-1] == '0' && len > 0) len--;

        if ( buf[len-1] == '.' ) len--; /* eat the trailing decimal */

        version = savepvn(buf, len);
        SAVEFREEPV(version);
        SvREFCNT_dec(sv);
    }
#ifdef SvVOK
    else if ( (mg = SvVSTRING_mg(ver)) ) { /* already a v-string */
        version = savepvn( (const char*)mg->mg_ptr,mg->mg_len );
        SAVEFREEPV(version);
        qv = TRUE;
    }
#endif
    else if ( SvPOK(ver))/* must be a string or something like a string */
VER_PV:
    {
        STRLEN len;
        version = savepvn(SvPV(ver,len), SvCUR(ver));
        SAVEFREEPV(version);
#ifndef SvVOK
        /* This will only be executed for 5.6.0 - 5.8.0 inclusive */
        if ( len >= 3 && !instr(version,".") && !instr(version,"_")) {
            /* may be a v-string */
            char *testv = (char *)version;
            STRLEN tlen = len;
            for (tlen=0; tlen < len; tlen++, testv++) {
                /* if one of the characters is non-text assume v-string */
                if (testv[0] < ' ') {
                    SV * const nsv = sv_newmortal();
                    const char *nver;
                    const char *pos;
                    int saw_decimal = 0;
                    sv_setpvf(nsv,"v%vd",ver);
                    pos = nver = savepv(SvPV_nolen(nsv));
                    SAVEFREEPV(pos);

                    /* scan the resulting formatted string */
                    pos++; /* skip the leading 'v' */
                    while ( *pos == '.' || isDIGIT(*pos) ) {
                        if ( *pos == '.' )
                            saw_decimal++ ;
                        pos++;
                    }

                    /* is definitely a v-string */
                    if ( saw_decimal >= 2 ) {
                        version = nver;
                    }
                    break;
                }
            }
        }
#endif
    }
#if PERL_VERSION_LT(5,17,2)
    else if (SvIOKp(ver)) {
        goto VER_IV;
    }
    else if (SvNOKp(ver)) {
        goto VER_NV;
    }
    else if (SvPOKp(ver)) {
        goto VER_PV;
    }
#endif
    else
    {
        /* no idea what this is */
        Perl_croak(aTHX_ "Invalid version format (non-numeric data)");
    }

    s = SCAN_VERSION(version, ver, qv);
    if ( *s != '\0' )
        Perl_ck_warner(aTHX_ packWARN(WARN_MISC),
                       "Version string '%s' contains invalid data; "
                       "ignoring: '%s'", version, s);

#if PERL_VERSION_LT(5,19,8) && defined(USE_ITHREADS)
    LEAVE;
#endif

    return ver;
}

/*
=for apidoc vverify

Validates that the SV contains valid internal structure for a version object.
It may be passed either the version object (RV) or the hash itself (HV).  If
the structure is valid, it returns the HV.  If the structure is invalid,
it returns NULL.

    SV *hv = vverify(sv);

Note that it only confirms the bare minimum structure (so as not to get
confused by derived classes which may contain additional hash entries):

=over 4

=item * The SV is an HV or a reference to an HV

=item * The hash contains a "version" key

=item * The "version" key has a reference to an AV as its value

=back

=cut
*/

SV *
#ifdef VUTIL_REPLACE_CORE
Perl_vverify2(pTHX_ SV *vs)
#else
Perl_vverify(pTHX_ SV *vs)
#endif
{
    SV *sv;
    SV **svp;

    PERL_ARGS_ASSERT_VVERIFY;

    if ( SvROK(vs) )
        vs = SvRV(vs);

    /* see if the appropriate elements exist */
    if ( SvTYPE(vs) == SVt_PVHV
         && (svp = hv_fetchs(MUTABLE_HV(vs), "version", FALSE))
         && (sv = SvRV(*svp))
         && SvTYPE(sv) == SVt_PVAV )
        return vs;
    else
        return NULL;
}

/*
=for apidoc vnumify

Accepts a version object and returns the normalized floating
point representation.  Call like:

    sv = vnumify(rv);

NOTE: you can pass either the object directly or the SV
contained within the RV.

The SV returned has a refcount of 1.

=cut
*/

SV *
#ifdef VUTIL_REPLACE_CORE
Perl_vnumify2(pTHX_ SV *vs)
#else
Perl_vnumify(pTHX_ SV *vs)
#endif
{
    SSize_t i, len;
    I32 digit;
    bool alpha = FALSE;
    SV *sv;
    AV *av;

    PERL_ARGS_ASSERT_VNUMIFY;

    /* extract the HV from the object */
    vs = VVERIFY(vs);
    if ( ! vs )
        Perl_croak(aTHX_ "Invalid version object");

    /* see if various flags exist */
    if ( hv_exists(MUTABLE_HV(vs), "alpha", 5 ) )
        alpha = TRUE;

    if (alpha) {
        Perl_ck_warner(aTHX_ packWARN(WARN_NUMERIC),
                       "alpha->numify() is lossy");
    }

    /* attempt to retrieve the version array */
    if ( !(av = MUTABLE_AV(SvRV(*hv_fetchs(MUTABLE_HV(vs), "version", FALSE))) ) ) {
        return newSVpvs("0");
    }

    len = av_len(av);
    if ( len == -1 )
    {
        return newSVpvs("0");
    }

    {
        SV * tsv = *av_fetch(av, 0, 0);
        digit = SvIV(tsv);
    }
    sv = Perl_newSVpvf(aTHX_ "%d.", (int)PERL_ABS(digit));
    for ( i = 1 ; i <= len ; i++ )
    {
        SV * tsv = *av_fetch(av, i, 0);
        digit = SvIV(tsv);
        Perl_sv_catpvf(aTHX_ sv, "%03d", (int)digit);
    }

    if ( len == 0 ) {
        sv_catpvs(sv, "000");
    }
    return sv;
}

/*
=for apidoc vnormal

Accepts a version object and returns the normalized string
representation.  Call like:

    sv = vnormal(rv);

NOTE: you can pass either the object directly or the SV
contained within the RV.

The SV returned has a refcount of 1.

=cut
*/

SV *
#ifdef VUTIL_REPLACE_CORE
Perl_vnormal2(pTHX_ SV *vs)
#else
Perl_vnormal(pTHX_ SV *vs)
#endif
{
    I32 i, len, digit;
    SV *sv;
    AV *av;

    PERL_ARGS_ASSERT_VNORMAL;

    /* extract the HV from the object */
    vs = VVERIFY(vs);
    if ( ! vs )
        Perl_croak(aTHX_ "Invalid version object");

    av = MUTABLE_AV(SvRV(*hv_fetchs(MUTABLE_HV(vs), "version", FALSE)));

    len = av_len(av);
    if ( len == -1 )
    {
        return newSVpvs("");
    }
    {
        SV * tsv = *av_fetch(av, 0, 0);
        digit = SvIV(tsv);
    }
    sv = Perl_newSVpvf(aTHX_ "v%" IVdf, (IV)digit);
    for ( i = 1 ; i <= len ; i++ ) {
        SV * tsv = *av_fetch(av, i, 0);
        digit = SvIV(tsv);
        Perl_sv_catpvf(aTHX_ sv, ".%" IVdf, (IV)digit);
    }

    if ( len <= 2 ) { /* short version, must be at least three */
        for ( len = 2 - len; len != 0; len-- )
            sv_catpvs(sv,".0");
    }
    return sv;
}

/*
=for apidoc vstringify

In order to maintain maximum compatibility with earlier versions
of Perl, this function will return either the floating point
notation or the multiple dotted notation, depending on whether
the original version contained 1 or more dots, respectively.

The SV returned has a refcount of 1.

=cut
*/

SV *
#ifdef VUTIL_REPLACE_CORE
Perl_vstringify2(pTHX_ SV *vs)
#else
Perl_vstringify(pTHX_ SV *vs)
#endif
{
    SV ** svp;
    PERL_ARGS_ASSERT_VSTRINGIFY;

    /* extract the HV from the object */
    vs = VVERIFY(vs);
    if ( ! vs )
        Perl_croak(aTHX_ "Invalid version object");

    svp = hv_fetchs(MUTABLE_HV(vs), "original", FALSE);
    if (svp) {
        SV *pv;
        pv = *svp;
        if ( SvPOK(pv)
#if PERL_VERSION_LT(5,17,2)
            || SvPOKp(pv)
#endif
        )
            return newSVsv(pv);
        else
            return &PL_sv_undef;
    }
    else {
        if ( hv_exists(MUTABLE_HV(vs), "qv", 2) )
            return VNORMAL(vs);
        else
            return VNUMIFY(vs);
    }
}

/*
=for apidoc vcmp

Version object aware cmp.  Both operands must already have been
converted into version objects.

=cut
*/

int
#ifdef VUTIL_REPLACE_CORE
Perl_vcmp2(pTHX_ SV *lhv, SV *rhv)
#else
Perl_vcmp(pTHX_ SV *lhv, SV *rhv)
#endif
{
    SSize_t i,l,m,r;
    I32 retval;
    I32 left = 0;
    I32 right = 0;
    AV *lav, *rav;

    PERL_ARGS_ASSERT_VCMP;

    /* extract the HVs from the objects */
    lhv = VVERIFY(lhv);
    rhv = VVERIFY(rhv);
    if ( ! ( lhv && rhv ) )
        Perl_croak(aTHX_ "Invalid version object");

    /* get the left hand term */
    lav = MUTABLE_AV(SvRV(*hv_fetchs(MUTABLE_HV(lhv), "version", FALSE)));

    /* and the right hand term */
    rav = MUTABLE_AV(SvRV(*hv_fetchs(MUTABLE_HV(rhv), "version", FALSE)));

    l = av_len(lav);
    r = av_len(rav);
    m = l < r ? l : r;
    retval = 0;
    i = 0;
    while ( i <= m && retval == 0 )
    {
        SV * const lsv = *av_fetch(lav,i,0);
        SV * rsv;
        left = SvIV(lsv);
        rsv = *av_fetch(rav,i,0);
        right = SvIV(rsv);
        if ( left < right  )
            retval = -1;
        if ( left > right )
            retval = +1;
        i++;
    }

    if ( l != r && retval == 0 ) /* possible match except for trailing 0's */
    {
        if ( l < r )
        {
            while ( i <= r && retval == 0 )
            {
                SV * const rsv = *av_fetch(rav,i,0);
                if ( SvIV(rsv) != 0 )
                    retval = -1; /* not a match after all */
                i++;
            }
        }
        else
        {
            while ( i <= l && retval == 0 )
            {
                SV * const lsv = *av_fetch(lav,i,0);
                if ( SvIV(lsv) != 0 )
                    retval = +1; /* not a match after all */
                i++;
            }
        }
    }
    return retval;
}

/* ex: set ro: */