xref: /llvm-project-15.0.7/libcxx/src/ios.cpp (revision bbb0f2c7)

//===----------------------------------------------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//

#include <__config>
#include <__locale>
#include <algorithm>
#include <ios>
#include <limits>
#include <memory>
#include <new>
#include <stdlib.h>
#include <string>

#include "include/config_elast.h"

_LIBCPP_PUSH_MACROS
#include <__undef_macros>

_LIBCPP_BEGIN_NAMESPACE_STD

class _LIBCPP_HIDDEN __iostream_category
    : public __do_message
{
public:
    virtual const char* name() const noexcept;
    virtual string message(int ev) const;
};

const char*
__iostream_category::name() const noexcept
{
    return "iostream";
}

string
__iostream_category::message(int ev) const
{
    if (ev != static_cast<int>(io_errc::stream)
#ifdef _LIBCPP_ELAST
        && ev <= _LIBCPP_ELAST
#endif // _LIBCPP_ELAST
        )
        return __do_message::message(ev);
    return string("unspecified iostream_category error");
}

const error_category&
iostream_category() noexcept
{
    static __iostream_category s;
    return s;
}

// ios_base::failure

ios_base::failure::failure(const string& msg, const error_code& ec)
    : system_error(ec, msg)
{
}

ios_base::failure::failure(const char* msg, const error_code& ec)
    : system_error(ec, msg)
{
}

ios_base::failure::~failure() throw()
{
}

// ios_base locale

const ios_base::fmtflags ios_base::boolalpha;
const ios_base::fmtflags ios_base::dec;
const ios_base::fmtflags ios_base::fixed;
const ios_base::fmtflags ios_base::hex;
const ios_base::fmtflags ios_base::internal;
const ios_base::fmtflags ios_base::left;
const ios_base::fmtflags ios_base::oct;
const ios_base::fmtflags ios_base::right;
const ios_base::fmtflags ios_base::scientific;
const ios_base::fmtflags ios_base::showbase;
const ios_base::fmtflags ios_base::showpoint;
const ios_base::fmtflags ios_base::showpos;
const ios_base::fmtflags ios_base::skipws;
const ios_base::fmtflags ios_base::unitbuf;
const ios_base::fmtflags ios_base::uppercase;
const ios_base::fmtflags ios_base::adjustfield;
const ios_base::fmtflags ios_base::basefield;
const ios_base::fmtflags ios_base::floatfield;

const ios_base::iostate ios_base::badbit;
const ios_base::iostate ios_base::eofbit;
const ios_base::iostate ios_base::failbit;
const ios_base::iostate ios_base::goodbit;

const ios_base::openmode ios_base::app;
const ios_base::openmode ios_base::ate;
const ios_base::openmode ios_base::binary;
const ios_base::openmode ios_base::in;
const ios_base::openmode ios_base::out;
const ios_base::openmode ios_base::trunc;

void
ios_base::__call_callbacks(event ev)
{
    for (size_t i = __event_size_; i;)
    {
        --i;
        __fn_[i](ev, *this, __index_[i]);
    }
}

// locale

locale
ios_base::imbue(const locale& newloc)
{
    static_assert(sizeof(locale) == sizeof(__loc_), "");
    locale& loc_storage = *reinterpret_cast<locale*>(&__loc_);
    locale oldloc = loc_storage;
    loc_storage = newloc;
    __call_callbacks(imbue_event);
    return oldloc;
}

locale
ios_base::getloc() const
{
    const locale& loc_storage = *reinterpret_cast<const locale*>(&__loc_);
    return loc_storage;
}

// xalloc
#if defined(_LIBCPP_HAS_C_ATOMIC_IMP) && !defined(_LIBCPP_HAS_NO_THREADS)
atomic<int> ios_base::__xindex_{0};
#else
int ios_base::__xindex_ = 0;
#endif

template <typename _Tp>
static size_t __ios_new_cap(size_t __req_size, size_t __current_cap)
{ // Precondition: __req_size > __current_cap
	const size_t mx = std::numeric_limits<size_t>::max() / sizeof(_Tp);
	if (__req_size < mx/2)
		return _VSTD::max(2 * __current_cap, __req_size);
	else
		return mx;
}

int
ios_base::xalloc()
{
    return __xindex_++;
}

long&
ios_base::iword(int index)
{
    size_t req_size = static_cast<size_t>(index)+1;
    if (req_size > __iarray_cap_)
    {
        size_t newcap = __ios_new_cap<long>(req_size, __iarray_cap_);
        long* iarray = static_cast<long*>(realloc(__iarray_, newcap * sizeof(long)));
        if (iarray == 0)
        {
            setstate(badbit);
            static long error;
            error = 0;
            return error;
        }
        __iarray_ = iarray;
        for (long* p = __iarray_ + __iarray_size_; p < __iarray_ + newcap; ++p)
            *p = 0;
        __iarray_cap_ = newcap;
    }
    __iarray_size_ = max<size_t>(__iarray_size_, req_size);
    return __iarray_[index];
}

void*&
ios_base::pword(int index)
{
    size_t req_size = static_cast<size_t>(index)+1;
    if (req_size > __parray_cap_)
    {
        size_t newcap = __ios_new_cap<void *>(req_size, __iarray_cap_);
        void** parray = static_cast<void**>(realloc(__parray_, newcap * sizeof(void *)));
        if (parray == 0)
        {
            setstate(badbit);
            static void* error;
            error = 0;
            return error;
        }
        __parray_ = parray;
        for (void** p = __parray_ + __parray_size_; p < __parray_ + newcap; ++p)
            *p = 0;
        __parray_cap_ = newcap;
    }
    __parray_size_ = max<size_t>(__parray_size_, req_size);
    return __parray_[index];
}

// register_callback

void
ios_base::register_callback(event_callback fn, int index)
{
    size_t req_size = __event_size_ + 1;
    if (req_size > __event_cap_)
    {
        size_t newcap = __ios_new_cap<event_callback>(req_size, __event_cap_);
        event_callback* fns = static_cast<event_callback*>(realloc(__fn_, newcap * sizeof(event_callback)));
        if (fns == 0)
            setstate(badbit);
        __fn_ = fns;
        int* indxs = static_cast<int *>(realloc(__index_, newcap * sizeof(int)));
        if (indxs == 0)
            setstate(badbit);
        __index_ = indxs;
        __event_cap_ = newcap;
    }
    __fn_[__event_size_] = fn;
    __index_[__event_size_] = index;
    ++__event_size_;
}

ios_base::~ios_base()
{
    __call_callbacks(erase_event);
    locale& loc_storage = *reinterpret_cast<locale*>(&__loc_);
    loc_storage.~locale();
    free(__fn_);
    free(__index_);
    free(__iarray_);
    free(__parray_);
}

// iostate

void
ios_base::clear(iostate state)
{
    if (__rdbuf_)
        __rdstate_ = state;
    else
        __rdstate_ = state | badbit;

    if (((state | (__rdbuf_ ? goodbit : badbit)) & __exceptions_) != 0)
        __throw_failure("ios_base::clear");
}

// init

void
ios_base::init(void* sb)
{
    __rdbuf_ = sb;
    __rdstate_ = __rdbuf_ ? goodbit : badbit;
    __exceptions_ = goodbit;
    __fmtflags_ = skipws | dec;
    __width_ = 0;
    __precision_ = 6;
    __fn_ = 0;
    __index_ = 0;
    __event_size_ = 0;
    __event_cap_ = 0;
    __iarray_ = 0;
    __iarray_size_ = 0;
    __iarray_cap_ = 0;
    __parray_ = 0;
    __parray_size_ = 0;
    __parray_cap_ = 0;
    ::new(&__loc_) locale;
}

void
ios_base::copyfmt(const ios_base& rhs)
{
    // If we can't acquire the needed resources, throw bad_alloc (can't set badbit)
    // Don't alter *this until all needed resources are acquired
    unique_ptr<event_callback, void (*)(void*)> new_callbacks(0, free);
    unique_ptr<int, void (*)(void*)> new_ints(0, free);
    unique_ptr<long, void (*)(void*)> new_longs(0, free);
    unique_ptr<void*, void (*)(void*)> new_pointers(0, free);
    if (__event_cap_ < rhs.__event_size_)
    {
        size_t newesize = sizeof(event_callback) * rhs.__event_size_;
        new_callbacks.reset(static_cast<event_callback*>(malloc(newesize)));
        if (!new_callbacks)
            __throw_bad_alloc();

        size_t newisize = sizeof(int) * rhs.__event_size_;
        new_ints.reset(static_cast<int *>(malloc(newisize)));
        if (!new_ints)
            __throw_bad_alloc();
    }
    if (__iarray_cap_ < rhs.__iarray_size_)
    {
        size_t newsize = sizeof(long) * rhs.__iarray_size_;
        new_longs.reset(static_cast<long*>(malloc(newsize)));
        if (!new_longs)
            __throw_bad_alloc();
    }
    if (__parray_cap_ < rhs.__parray_size_)
    {
        size_t newsize = sizeof(void*) * rhs.__parray_size_;
        new_pointers.reset(static_cast<void**>(malloc(newsize)));
        if (!new_pointers)
            __throw_bad_alloc();
    }
    // Got everything we need.  Copy everything but __rdstate_, __rdbuf_ and __exceptions_
    __fmtflags_ = rhs.__fmtflags_;
    __precision_ = rhs.__precision_;
    __width_ = rhs.__width_;
    locale& lhs_loc = *reinterpret_cast<locale*>(&__loc_);
    const locale& rhs_loc = *reinterpret_cast<const locale*>(&rhs.__loc_);
    lhs_loc = rhs_loc;
    if (__event_cap_ < rhs.__event_size_)
    {
        free(__fn_);
        __fn_ = new_callbacks.release();
        free(__index_);
        __index_ = new_ints.release();
        __event_cap_ = rhs.__event_size_;
    }
    for (__event_size_ = 0; __event_size_ < rhs.__event_size_; ++__event_size_)
    {
        __fn_[__event_size_] = rhs.__fn_[__event_size_];
        __index_[__event_size_] = rhs.__index_[__event_size_];
    }
    if (__iarray_cap_ < rhs.__iarray_size_)
    {
        free(__iarray_);
        __iarray_ = new_longs.release();
        __iarray_cap_ = rhs.__iarray_size_;
    }
    for (__iarray_size_ = 0; __iarray_size_ < rhs.__iarray_size_; ++__iarray_size_)
        __iarray_[__iarray_size_] = rhs.__iarray_[__iarray_size_];
    if (__parray_cap_ < rhs.__parray_size_)
    {
        free(__parray_);
        __parray_ = new_pointers.release();
        __parray_cap_ = rhs.__parray_size_;
    }
    for (__parray_size_ = 0; __parray_size_ < rhs.__parray_size_; ++__parray_size_)
        __parray_[__parray_size_] = rhs.__parray_[__parray_size_];
}

void
ios_base::move(ios_base& rhs)
{
    // *this is uninitialized
    __fmtflags_ = rhs.__fmtflags_;
    __precision_ = rhs.__precision_;
    __width_ = rhs.__width_;
    __rdstate_ = rhs.__rdstate_;
    __exceptions_ = rhs.__exceptions_;
    __rdbuf_ = 0;
    locale& rhs_loc = *reinterpret_cast<locale*>(&rhs.__loc_);
    ::new(&__loc_) locale(rhs_loc);
    __fn_ = rhs.__fn_;
    rhs.__fn_ = 0;
    __index_ = rhs.__index_;
    rhs.__index_ = 0;
    __event_size_ = rhs.__event_size_;
    rhs.__event_size_ = 0;
    __event_cap_ = rhs.__event_cap_;
    rhs.__event_cap_ = 0;
    __iarray_ = rhs.__iarray_;
    rhs.__iarray_ = 0;
    __iarray_size_ = rhs.__iarray_size_;
    rhs.__iarray_size_ = 0;
    __iarray_cap_ = rhs.__iarray_cap_;
    rhs.__iarray_cap_ = 0;
    __parray_ = rhs.__parray_;
    rhs.__parray_ = 0;
    __parray_size_ = rhs.__parray_size_;
    rhs.__parray_size_ = 0;
    __parray_cap_ = rhs.__parray_cap_;
    rhs.__parray_cap_ = 0;
}

void
ios_base::swap(ios_base& rhs) noexcept
{
    _VSTD::swap(__fmtflags_, rhs.__fmtflags_);
    _VSTD::swap(__precision_, rhs.__precision_);
    _VSTD::swap(__width_, rhs.__width_);
    _VSTD::swap(__rdstate_, rhs.__rdstate_);
    _VSTD::swap(__exceptions_, rhs.__exceptions_);
    locale& lhs_loc = *reinterpret_cast<locale*>(&__loc_);
    locale& rhs_loc = *reinterpret_cast<locale*>(&rhs.__loc_);
    _VSTD::swap(lhs_loc, rhs_loc);
    _VSTD::swap(__fn_, rhs.__fn_);
    _VSTD::swap(__index_, rhs.__index_);
    _VSTD::swap(__event_size_, rhs.__event_size_);
    _VSTD::swap(__event_cap_, rhs.__event_cap_);
    _VSTD::swap(__iarray_, rhs.__iarray_);
    _VSTD::swap(__iarray_size_, rhs.__iarray_size_);
    _VSTD::swap(__iarray_cap_, rhs.__iarray_cap_);
    _VSTD::swap(__parray_, rhs.__parray_);
    _VSTD::swap(__parray_size_, rhs.__parray_size_);
    _VSTD::swap(__parray_cap_, rhs.__parray_cap_);
}

void
ios_base::__set_badbit_and_consider_rethrow()
{
    __rdstate_ |= badbit;
#ifndef _LIBCPP_NO_EXCEPTIONS
    if (__exceptions_ & badbit)
        throw;
#endif // _LIBCPP_NO_EXCEPTIONS
}

void
ios_base::__set_failbit_and_consider_rethrow()
{
    __rdstate_ |= failbit;
#ifndef _LIBCPP_NO_EXCEPTIONS
    if (__exceptions_ & failbit)
        throw;
#endif // _LIBCPP_NO_EXCEPTIONS
}

bool
ios_base::sync_with_stdio(bool sync)
{
    static bool previous_state = true;
    bool r = previous_state;
    previous_state = sync;
    return r;
}

_LIBCPP_END_NAMESPACE_STD

_LIBCPP_POP_MACROS