void
test_extractor (CharT*, Traits*, ArithmeticType*,
                const char     *cname,
                const char     *tname,
                const char     *aname,
                int             line,
                // printf formatting directive for ArithmeticType
                const char *valfmt,
                // character buffer (input sequence)
                const char *cbuf,
                // number of characters in buffer:
                std::size_t cbuf_size,
                // ctype and numpunct data
                const LocaleData &locale_data,
                // stream flags():
                int flags,
                // initial stream rdstate():
                int init_state,
                // unmasked exceptions:
                int exceptions,
                // expected exception:
                int expect_exception,
                // expected stream state after extraction:
                int expect_state,
                // expected number of extracted characters:
                int expect_extract,
                // have streambuf fail (or throw) after so many calls
                // to underflow() (each call extracts a single chracter):
                int fail_when,
                // initial value of the argument to extractor:
                ArithmeticType init_value,
                // expected value of the argument after extraction:
                ArithmeticType expect_value)
{
    _RWSTD_UNUSED (cname);
    _RWSTD_UNUSED (tname);

    typedef std::basic_istream<CharT, Traits> Istream;
    typedef MyStreambuf<CharT, Traits>        Streambuf;

    const char *fail_desc = 0;

    int fail_how = 0;

    if (fail_when < 0) {
        // have the stream buffer object's underflow() fail (by throwing
        // an exception if possible) after `fail_when' characters have
        // been extracted (this object calls underflow() for every char)
        fail_how  = Underflow | Throw;
        fail_when = -fail_when;
        fail_desc = "threw";
    }
    else if (0 < fail_when) {
        // have the stream buffer object's underflow() fail by returning
        // eof after `fail_when' characters have been extracted (this
        // object calls underflow() for every char)
        fail_how  = Underflow;
        fail_desc = "returned EOF";
    }

    // construct a stream buffer object and initialize its read sequence
    // with the character buffer
    Streambuf sb (cbuf, cbuf_size, fail_how, fail_when);

    // construct an istream object and initialize it with the user
    // defined streambuf object
    Istream is (&sb);

    if (-1 == flags) {
        // get the initial stream object's format control flags
        flags = is.flags ();
    }
    else {
        // set the stream object's format control flags
        is.flags (std::ios::fmtflags (flags));
    }

    if (-1 == exceptions) {
        // get the initial stream object's exceptions
        exceptions = is.exceptions ();
    }
    else {
        // unmask the stream objects exceptions (must be done
        // before calling setstate() to prevent the latter from
        // throwing ios::failure)
        is.exceptions (std::ios::iostate (exceptions));
    }

    if (-1 == init_state) {
        // get the initial stream object's state
        init_state = is.rdstate ();
    }
    else {
        // set the stream object's initial state

#ifndef _RWSTD_NO_EXCEPTIONS
        try {
            is.setstate (std::ios::iostate (init_state));
        }
        catch (...) {
            // ignore exceptions
        }
#else   // if defined ( _RWSTD_NO_EXCEPTIONS)
        is.setstate (std::ios::iostate (init_state));
#endif   //  _RWSTD_NO_EXCEPTIONS
    }

    // construct a locale object that treats only the specified `white'
    // characters as whitespace (all others are treated normally)
    const std::locale loc =
        is.imbue (make_locale ((CharT*)0, (Traits*)0, locale_data));

    // imbue the previous locale into the stream buffer to verify that
    // the ws manipulator uses the locale imbued in the stream object
    // and not the one in the stream buffer
    sb.pubimbue (loc);

    // initialize the variable to the initial value to detect
    // the extractor setting it when it's not supposed to
    ArithmeticType value = init_value;

    // format the FUNCALL environment variable w/o writing out any output
    rw_fprintf (0,
                "%{$FUNCALL!:@}",
                "%{$CLASS}(%{*Ac}).operator>>(%s& = %{@}): "
                "initial flags() = %{If}, rdstate() = %{Is}, "
                "exceptions() = %{Is}, whitespace = %{#s}, numpunct = { "
                ".dp=%{#c}, .ts=%{#c}, .grp=%{#s}, .fn=%{#s}, .tn=%{#s} }",
                int (sizeof *cbuf), cbuf, aname, valfmt, init_value,
                flags, init_state,
                exceptions, locale_data.whitespace,
                locale_data.decimal_point, locale_data.thousands_sep,
                locale_data.grouping, locale_data.falsename,
                locale_data.truename);

#ifndef _RWSTD_NO_EXCEPTIONS

    int caught = 0;

    try {
        is >> value;
    }
    catch (Exception&) {
        caught = 1;
    }
    catch (std::ios_base::failure &ex) {
        caught = 2;
        rw_assert (caught == expect_exception, 0, line,
                   "line %d. %{$FUNCALL}: unexpectedly threw "
                   "ios_base::failure(%{#s})", __LINE__, ex.what ());
    }
    catch (...) {
        caught = -1;
        rw_assert (false, 0, line,
                   "line %d. %{$FUNCALL}: unexpectely threw an exception "
                   "of unknown type", __LINE__);
    }

    //////////////////////////////////////////////////////////////////
    // verify that the function propagates exceptions thrown from the
    // streambuf object only when badbit is set in the stream object's
    // exceptions()

    rw_assert (caught == expect_exception, 0, line,
               "line %d. %{$FUNCALL}: "
               "%{?}failed to throw"
               "%{:}unexpectedly propagated"
               "%{;} exception",
               __LINE__, expect_exception);

#else   // if defined (_RWSTD_NO_EXCEPTIONS)

    is >> value;

#endif   // _RWSTD_NO_EXCEPTIONS

    // clear the text describing the type of failure when streambuf
    // didn't actually fail (or throw)
    if (sb.failed_ == None && sb.threw_ == None)
        fail_desc = 0;

    //////////////////////////////////////////////////////////////////
    // verify that the expected number of characters have been
    // extracted from the stream

    const int extracted = int (sb.pubgptr () - sb.pubeback ());

    rw_assert (expect_extract == extracted, 0, line,
               "%d. %{$FUNCALL}: expected to extract %d characters, "
               "got %d%{?} (underflow() %s at extraction %u)%{;}",
               __LINE__, expect_extract,
               extracted, 0 != fail_desc, fail_desc, fail_when);

    //////////////////////////////////////////////////////////////////
    // verify that gcount() is not affected

    if (0 == opt_no_gcount)
        rw_assert (0 == is.gcount (), 0, line,
                   "%d. %{$FUNCALL}: gcount() == 0, got %d "
                   "%{?} (underflow() %s at extraction %u)%{;}",
                   __LINE__, is.gcount (),
                   0 != fail_desc, fail_desc, fail_when);

    //////////////////////////////////////////////////////////////////
    // verify the state of the stream object after the function call

    rw_assert (is.rdstate () == expect_state, 0, line,
               "line %d. %{$FUNCALL}: rdstate() == %{Is}, got %{Is}"
               "%{?} (underflow() %s at extraction %u)%{;}",
               __LINE__, expect_state, is.rdstate(),
               0 != fail_desc, fail_desc, fail_when);

    //////////////////////////////////////////////////////////////////
    // verify the extracted value matches the expected value

    rw_assert (expect_value == value, 0, line,
               "line %d. %{$FUNCALL}: expected value %{@}, got %{@}",
               __LINE__, valfmt, expect_value, valfmt, value);
}
Example #2
0
void test_readsome (const charT *cbuf, const Traits*,
                    unsigned cbuf_size,
                    unsigned i,   // index into states
                    unsigned j,   // number of chars to read
                    unsigned k,   // when underflow() will fail
                    int      l,   // value returned from showmanyc()
                    unsigned m)   // how underflow should fail()
{
    typedef std::basic_istream<charT, Traits> Istream;

    static unsigned iter = 0;   // iteration counter

    // construct a stream buffer object and initialize its read
    // sequence with the character buffer
    Streambuf<charT, Traits> sb (cbuf, cbuf + cbuf_size - 1);

    sb.showmanyc_ = l;

    const char* err_type = 0;

    if (m < 1) {
        // have the stream buffer object's underflow() fail (by
        // throwing an exception if possible) after k characters
        // have been extracted (this object calls underflow() for
        // every char)
        sb.throw_after_ = k;
        err_type        = "threw";
    }
    else {
        // have the stream buffer object's underflow() fail by
        // returning eof after k characters have been extracted
        // (this object calls underflow() for every char)
        sb.fail_after_ = k;
        err_type       = "returned EOF";
    }

    // construct an istream object and initialize it with the user
    // defined streambuf object
    Istream is (&sb);

    // set the stream object's initial state
    is.setstate (states [i]);

    // the number of extracted whitespace characters expected to
    // be reported by gcount() must equal the number of successful
    // extractions computed by the the stream buffer overridden
    // underflow member function
    const int extract =
        is.good () ? j < k ? int (j) < l ? j
                                         : l < 0 ? 0 : l
                           : int (k) < l ? k
                                         : l < 0 ? 0 : l
                   : 0;

    charT buf [256] = { 0 };

    std::streamsize nread = -1;

    // format the FCALL environment variable so that it can be
    // conveniently used in diagnostics below
    rw_fprintf (0, "%u. %{$FCALL!:@}",
                iter,
                "%{$ISTREAM}(%{*Ac}).readsome(%p, %d)",
                int (sizeof *cbuf), cbuf, buf, j);

#ifndef _RWSTD_NO_EXCEPTIONS

    const char *caught = 0;

    // on every other iteration set badbit in exceptions to check
    // that the thrown object is propagated by the function
    if (k % 2 && !is.bad ())
        is.exceptions (std::ios_base::badbit);

    try {
        nread = is.readsome (buf, j);
    }
    catch (const char *s) {
        caught = s;
    }
    catch (...) {

        caught = "...";

        rw_assert (0, 0, __LINE__,
                   "%{$FCALL} threw an exception of unexpected type");
    }

    //////////////////////////////////////////////////////////////////
    // verify that the function propagates exceptions thrown from the
    // streambuf object only when badbit is set in the stream object's
    // exceptions()

    rw_assert (!caught || (k % 2), 0, __LINE__,
               "%{$FCALL} unexpectedly propagated an exception");

#else   // if defined (_RWSTD_NO_EXCEPTIONS)

    nread = is.readsome (buf, j);

#endif   // _RWSTD_NO_EXCEPTIONS

    //////////////////////////////////////////////////////////////////
    // verify that the function returned the expected number of
    // extracted characters

    const std::streamsize extracted = sb.pubgptr () - sb.pubeback ();

    rw_assert (extract == extracted, 0, __LINE__,
               "%{$FCALL} expected to extract %d chars, got %u; "
               "initial state = %{Is}, underflow %s at extraction %u",
               extract, extracted, states [i],
               err_type, k);

    //////////////////////////////////////////////////////////////////
    // verify that the expected number of characters have been
    // extracted from the stream

    rw_assert (cbuf + extract == sb.pubgptr (), 0, __LINE__,
               "%{$FCALL} expected to extract %d chars, got %u; "
               "initial state = %{Is}, underflow %s at extraction %u",
               extract, extracted, states [i],
               err_type, k);

    //////////////////////////////////////////////////////////////////
    // verify that the extracted characters match those in the buffer

    rw_assert (0 == std::char_traits<charT>::compare (buf, cbuf, extract),
               0, __LINE__,
               "%{$FCALL} expected to extract the first %d chars, got %{*Ac}",
               extract, int (sizeof *buf), buf);

    //////////////////////////////////////////////////////////////////
    // verify that gcount() correctly reflects the number of
    // characters successfully extracted from the stream

    rw_assert (extract == is.gcount (), 0, __LINE__,
               "%{$FCALL}: gcount() == %d, got %d; initial state = %{Is}, "
               "underflow %s at extraction %u",
               extract, is.gcount (), states [i],
               err_type, k);

    //////////////////////////////////////////////////////////////////
    // verify the state of the stream object after the function call

    // expected stream state after the function call is unchanged
    // (i.e., the initial stream state), except...
    std::ios_base::iostate expect_state = states [i];

    if (!states [i]) {

#ifndef _RWSTD_NO_EXCEPTIONS

        // ...if an extraction is attempted, or even if the first
        // character on the stream is peeked at, and an exception
        // is thrown during input, badbit should be set, otherwise
        // if in_avail() returned -1, eofbit should be set, else
        // the state should be good
        if (-2 == l)
            expect_state = std::ios_base::badbit;
        else if (l < 0)
            expect_state = std::ios_base::eofbit;
        else
            expect_state = std::ios_base::goodbit;

#else   // if defined (_RWSTD_NO_EXCEPTIONS)

        if (l < 0)
            expect_state = std::ios_base::eofbit;
        else
            expect_state = std::ios_base::goodbit;

#endif   // _RWSTD_NO_EXCEPTIONS

    }
    else {

        // ...if the initial stream state is not good, failbit
        // must be set
        expect_state = states [i] | std::ios_base::failbit;
    }

    rw_assert (is.rdstate () == expect_state, 0, __LINE__,
               "%{$FCALL}: rdstate() == %{Is}, got %{Is}; "
               "extracted %u characters; "
               "initial state = %{Is}, underflow %s at extraction %u",
               expect_state, is.rdstate (), extracted,
               states [i], err_type, k);

    ++iter;
}