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// This is part of the iostream library, providing -*- C++ -*- input/output.
// Copyright (C) 1991 Per Bothner.
//
// This library is free software; you can redistribute it and/or
// modify it under the terms of the GNU Library General Public
// License as published by the Free Software Foundation; either
// version 2 of the License, or (at your option) any later version.
//
// This library is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
// Library General Public License for more details.
//
// You should have received a copy of the GNU Library General Public
#ifndef _STREAMBUF_H
#define _STREAMBUF_H
#ifdef __GNUG__
#pragma interface
#endif
/* #define _G_IO_THROW */ /* Not implemented: ios::failure */
#include <_G_config.h>
#ifdef _G_NEED_STDARG_H
#include <stdarg.h>
#endif
#ifndef fpos_t
#define fpos_t _G_fpos_t
#endif
#ifndef EOF
#define EOF (-1)
#endif
#ifndef NULL
#define NULL ((void*)0)
#endif
class ostream; class streambuf; class backupbuf;
// In case some header files defines these as macros.
#undef open
#undef close
#ifdef _G_FRIEND_BUG
extern int __UNDERFLOW(streambuf*);
extern int __OVERFLOW(streambuf*, int);
#endif
extern "C" int __underflow(streambuf*);
extern "C" int __overflow(streambuf*, int);
typedef _G_off_t streamoff;
typedef _G_off_t streampos; // Should perhaps be _G_fpos_t ?
typedef unsigned long __fmtflags;
typedef unsigned char __iostate;
struct _ios_fields { // The data members of an ios.
streambuf *_strbuf;
ostream* _tie;
int _width;
__fmtflags _flags;
_G_wchar_t _fill;
__iostate _state;
__iostate _exceptions;
int _precision;
};
#define _IOS_GOOD 0
#define _IOS_EOF 1
#define _IOS_FAIL 2
#define _IOS_BAD 4
#define _IOS_INPUT 1
#define _IOS_OUTPUT 2
#define _IOS_ATEND 4
#define _IOS_APPEND 8
#define _IOS_TRUNC 16
#define _IOS_NOCREATE 32
#define _IOS_NOREPLACE 64
#define _IOS_BIN 128
#ifdef _STREAM_COMPAT
enum state_value {
_good = _IOS_GOOD,
_eof = _IOS_EOF,
_fail = _IOS_FAIL,
_bad = _IOS_BAD };
enum open_mode {
input = _IOS_INPUT,
output = _IOS_OUTPUT,
atend = _IOS_ATEND,
append = _IOS_APPEND };
#endif
class ios : public _ios_fields {
public:
typedef __fmtflags fmtflags;
typedef int iostate;
typedef int openmode;
enum io_state {
goodbit = _IOS_GOOD,
eofbit = _IOS_EOF,
failbit = _IOS_FAIL,
badbit = _IOS_BAD };
enum open_mode {
in = _IOS_INPUT,
out = _IOS_OUTPUT,
ate = _IOS_ATEND,
app = _IOS_APPEND,
trunc = _IOS_TRUNC,
nocreate = _IOS_NOCREATE,
noreplace = _IOS_NOREPLACE,
bin = _IOS_BIN };
enum seek_dir { beg, cur, end};
// ANSI: typedef enum seek_dir seekdir; etc
enum { skipws=01, left=02, right=04, internal=010,
dec=020, oct=040, hex=0100,
showbase=0200, showpoint=0400, uppercase=01000, showpos=02000,
scientific=04000, fixed=010000, unitbuf=020000, stdio=040000,
dont_close=0x80000000 //Don't delete streambuf on stream destruction
};
enum { // Masks.
basefield=dec+oct+hex,
floatfield = scientific+fixed,
adjustfield = left+right+internal
};
#ifdef _G_IO_THROW
class failure : public xmsg {
ios* _stream;
public:
failure(ios* stream) { _stream = stream; }
failure(string cause, ios* stream) { _stream = stream; }
ios* rdios() const { return _stream; }
};
#endif
ostream* tie() const { return _tie; }
ostream* tie(ostream* val) { ostream* save=_tie; _tie=val; return save; }
// Methods to change the format state.
_G_wchar_t fill() const { return (_G_wchar_t)_fill; }
_G_wchar_t fill(_G_wchar_t newf)
{_G_wchar_t oldf = (_G_wchar_t)_fill; _fill = (char)newf; return oldf;}
fmtflags flags() const { return _flags; }
fmtflags flags(fmtflags new_val) {
fmtflags old_val = _flags; _flags = new_val; return old_val; }
int precision() const { return _precision; }
int precision(int newp) {
unsigned short oldp = _precision; _precision = (unsigned short)newp;
return oldp; }
fmtflags setf(fmtflags val) {
fmtflags oldbits = _flags;
_flags |= val; return oldbits; }
fmtflags setf(fmtflags val, fmtflags mask) {
fmtflags oldbits = _flags;
_flags = (_flags & ~mask) | (val & mask); return oldbits; }
fmtflags unsetf(fmtflags mask) {
fmtflags oldbits = _flags & mask;
_flags &= ~mask; return oldbits; }
int width() const { return _width; }
int width(int val) { int save = _width; _width = val; return save; }
#ifdef _G_IO_THROW
void _throw_failure() { throw new ios::failure(this); }
#else
void _throw_failure() { }
#endif
streambuf* rdbuf() const { return _strbuf; }
void clear(iostate state = 0) {
_state = _strbuf ? state : state|badbit;
if (_state & _exceptions) _throw_failure(); }
void set(iostate flag) { _state |= flag;
if (_state & _exceptions) _throw_failure(); }
int good() const { return _state == 0; }
int eof() const { return _state & ios::eofbit; }
int fail() const { return _state & (ios::badbit|ios::failbit); }
int bad() const { return _state & ios::badbit; }
iostate rdstate() const { return _state; }
operator void*() const { return fail() ? (void*)0 : (void*)(-1); }
int operator!() const { return fail(); }
iostate exception(iostate enable) {
iostate old = _exceptions; _exceptions = enable;
if (_state & _exceptions) _throw_failure();
return old; }
static int sync_with_stdio(int on);
static void sync_with_stdio() { sync_with_stdio(1); }
#ifdef _STREAM_COMPAT
void unset(state_value flag) { _state &= ~flag; }
void close();
int is_open();
int readable();
int writable();
#endif
protected:
ios(streambuf* sb = 0, ostream* tie = 0);
virtual ~ios();
void init(streambuf* sb) { _state=0; _strbuf=sb; }
};
#if __GNUG__==1
typedef int _seek_dir;
#else
typedef ios::seek_dir _seek_dir;
#endif
// Magic numbers and bits for the _flags field.
// The magic numbers use the high-order bits of _flags;
// the remaining bits are abailable for variable flags.
// Note: The magic numbers must all be negative if stdio
// emulation is desired.
#define _IO_MAGIC 0xFBAD0000 /* Magic number */
#define _OLD_STDIO_MAGIC 0xFABC0000 /* Emulate old stdio. */
#define _IO_MAGIC_MASK 0xFFFF0000
#define _S_USER_BUF 1 /* User owns buffer; don't delete it on close. */
#define _S_UNBUFFERED 2
#define _S_NO_READS 4 /* Reading not allowed */
#define _S_NO_WRITES 8 /* Writing not allowd */
#define _S_EOF_SEEN 0x10
#define _S_ERR_SEEN 0x20
#define _S_DELETE_DONT_CLOSE 0x40
#define _S_LINKED 0x80 // Set if linked (using _chain) to streambuf::_list_all.
#define _S_IN_BACKUP 0x100
#define _S_LINE_BUF 0x200
#define _S_TIED_PUT_GET 0x400 // Set if put and get pointer logicly tied.
#define _S_CURRENTLY_PUTTING 0x800
#define _S_IS_APPENDING 0x1000
#define _S_IS_BACKUPBUF 0x4000
#define _S_IS_FILEBUF 0x8000
// A streammarker remembers a position in a buffer.
// You are guaranteed to be able to seek back to it if it is saving().
class streammarker {
friend class streambuf;
#ifdef _G_FRIEND_BUG
friend int __UNDERFLOW(streambuf*);
#else
friend int __underflow(streambuf*);
#endif
struct streammarker *_next; // Only if saving()
streambuf *_sbuf; // Only valid if saving().
streampos _spos; // -2: means that _pos is valid.
void set_streampos(streampos sp) { _spos = sp; }
void set_offset(int offset) { _pos = offset; _spos = (streampos)(-2); }
// If _pos >= 0, it points to _buf->Gbase()+_pos.
// if _pos < 0, it points to _buf->eBptr()+_pos.
int _pos;
public:
streammarker(streambuf *sb);
~streammarker();
int saving() { return _spos == -2; }
int delta(streammarker&);
int delta();
};
struct __streambuf {
// NOTE: If this is changed, also change __FILE in stdio/stdio.h!
int _flags; /* High-order word is _IO_MAGIC; rest is flags. */
char* _gptr; /* Current get pointer */
char* _egptr; /* End of get area. */
char* _eback; /* Start of putback+get area. */
char* _pbase; /* Start of put area. */
char* _pptr; /* Current put pointer. */
char* _epptr; /* End of put area. */
char* _base; /* Start of reserve area. */
char* _ebuf; /* End of reserve area. */
struct streambuf *_chain;
// The following fields are used to support backing up and undo.
friend class streammarker;
char *_other_gbase; // Pointer to start of non-current get area.
char *_aux_limit; // Pointer to first valid character of backup area,
char *_other_egptr; // Pointer to end of non-current get area.
streammarker *_markers;
#define __HAVE_COLUMN /* temporary */
// 1+column number of pbase(); 0 is unknown.
unsigned short _cur_column;
char _unused;
char _shortbuf[1];
};
extern unsigned __adjust_column(unsigned start, const char *line, int count);
struct streambuf : private __streambuf {
friend class ios;
friend class istream;
friend class ostream;
friend class streammarker;
#ifdef _G_FRIEND_BUG
friend int __UNDERFLOW(streambuf*);
#else
friend int __underflow(streambuf*);
#endif
protected:
static streambuf* _list_all; /* List of open streambufs. */
streambuf*& xchain() { return _chain; }
void _un_link();
void _link_in();
char* gptr() const { return _gptr; }
char* pptr() const { return _pptr; }
char* egptr() const { return _egptr; }
char* epptr() const { return _epptr; }
char* pbase() const { return _pbase; }
char* eback() const { return _eback; }
char* base() const { return _base; }
char* ebuf() const { return _ebuf; }
int blen() const { return _ebuf - _base; }
void xput_char(char c) { *_pptr++ = c; }
int xflags() { return _flags; }
int xflags(int f) { int fl = _flags; _flags = f; return fl; }
void xsetflags(int f) { _flags |= f; }
void xsetflags(int f, int mask) { _flags = (_flags & ~mask) | (f & mask); }
void gbump(int n) { _gptr += n; }
void pbump(int n) { _pptr += n; }
void setb(char* b, char* eb, int a=0);
void setp(char* p, char* ep) { _pbase=_pptr=p; _epptr=ep; }
void setg(char* eb, char* g, char *eg) { _eback=eb; _gptr=g; _egptr=eg; }
char *shortbuf() { return _shortbuf; }
int in_backup() { return _flags & _S_IN_BACKUP; }
// The start of the main get area: FIXME: wrong for write-mode filebuf?
char *Gbase() { return in_backup() ? _other_gbase : _eback; }
// The end of the main get area:
char *eGptr() { return in_backup() ? _other_egptr : _egptr; }
// The start of the backup area:
char *Bbase() { return in_backup() ? _eback : _other_gbase; }
char *Bptr() { return _aux_limit; }
// The end of the backup area:
char *eBptr() { return in_backup() ? _egptr : _other_egptr; }
char *Nbase() { return _other_gbase; }
char *eNptr() { return _other_egptr; }
int have_backup() { return _other_gbase != NULL; }
int have_markers() { return _markers != NULL; }
int _least_marker();
void switch_to_main_get_area();
void switch_to_backup_area();
void free_backup_area();
void unsave_markers(); // Make all streammarkers !saving().
int put_mode() { return _flags & _S_CURRENTLY_PUTTING; }
int switch_to_get_mode();
streambuf(int flags=0);
public:
static int flush_all();
static void flush_all_linebuffered(); // Flush all line buffered files.
virtual int underflow() = 0; // Leave public for now
virtual int overflow(int c = EOF) = 0; // Leave public for now
virtual int doallocate();
virtual streampos seekoff(streamoff, _seek_dir, int mode=ios::in|ios::out);
virtual streampos seekpos(streampos pos, int mode = ios::in|ios::out);
int seekmark(streammarker& mark, int delta = 0);
int sputbackc(char c);
int sungetc();
virtual ~streambuf();
int unbuffered() { return _flags & _S_UNBUFFERED ? 1 : 0; }
int linebuffered() { return _flags & _S_LINE_BUF ? 1 : 0; }
void unbuffered(int i)
{ if (i) _flags |= _S_UNBUFFERED; else _flags &= ~_S_UNBUFFERED; }
void linebuffered(int i)
{ if (i) _flags |= _S_LINE_BUF; else _flags &= ~_S_LINE_BUF; }
int allocate() { // For AT&T compatibility
if (base() || unbuffered()) return 0;
else return doallocate(); }
// Allocate a buffer if needed; use _shortbuf if appropriate.
void allocbuf() { if (base() == NULL) doallocbuf(); }
void doallocbuf();
virtual int sync();
virtual int pbackfail(int c);
virtual streambuf* setbuf(char* p, int len);
int in_avail() { return _egptr - _gptr; }
int out_waiting() { return _pptr - _pbase; }
virtual int xsputn(const char* s, int n);
int sputn(const char* s, int n) { return xsputn(s, n); }
int padn(char pad, int n); // Emit 'n' copies of 'pad'.
virtual int xsgetn(char* s, int n);
int sgetn(char* s, int n) { return xsgetn(s, n); }
int ignore(int);
virtual int get_column();
virtual int set_column(int);
long sgetline(char* buf, _G_size_t n, char delim, int putback_delim);
int sbumpc() {
if (_gptr >= _egptr && __underflow(this) == EOF) return EOF;
else return *(unsigned char*)_gptr++; }
int sgetc() {
if (_gptr >= _egptr && __underflow(this) == EOF) return EOF;
else return *(unsigned char*)_gptr; }
int snextc() {
if (_gptr >= _egptr && __underflow(this) == EOF) return EOF;
return _gptr++, sgetc(); }
int sputc(int c) {
if (_pptr >= _epptr) return __overflow(this, (unsigned char)c);
else return *_pptr++ = c, (unsigned char)c; }
void stossc() { if (_gptr < _egptr) _gptr++; }
int vscan(char const *fmt0, _G_va_list ap, ios* stream = NULL);
int scan(char const *fmt0 ...);
int vform(char const *fmt0, _G_va_list ap);
int form(char const *fmt0 ...);
#if 0 /* Work in progress */
int collumn(); // Current collumn number (of put pointer). -1 is unknown.
void collumn(int c); // Set collumn number of put pointer to c.
#endif
};
// A backupbuf is a streambuf with full backup and savepoints on reading.
// All standard streambufs in the GNU iostream library are backupbufs.
// A backupbuf may have two get area:
// - The main get area, and (sometimes) the putback area.
// Whichever one of these contains the gptr is the current get area;
// the other one is the non-current get area.
class backupbuf : public streambuf {
friend class streammarker;
protected:
backupbuf(int flags=0) : streambuf(flags|_S_IS_BACKUPBUF) { }
public:
virtual int pbackfail(int c);
virtual int underflow();
virtual int overflow(int c = EOF);
};
struct __file_fields {
short _fileno;
int _blksize;
fpos_t _offset;
// char* _save_gptr; char* _save_egptr;
};
class filebuf : public backupbuf {
protected:
struct __file_fields _fb;
void init();
public:
static const int openprot; // Non-ANSI AT&T-ism: Default open protection.
filebuf();
filebuf(int fd);
filebuf(int fd, char* p, int len);
~filebuf();
filebuf* attach(int fd);
filebuf* open(const char *filename, const char *mode);
filebuf* open(const char *filename, ios::openmode mode, int prot = 0664);
virtual int underflow();
virtual int overflow(int c = EOF);
int is_open() const { return _fb._fileno >= 0; }
int fd() const { return is_open() ? _fb._fileno : EOF; }
filebuf* close();
virtual int doallocate();
virtual streampos seekoff(streamoff, _seek_dir, int mode=ios::in|ios::out);
virtual streambuf* setbuf(char* p, int len);
int xsputn(const char* s, int n);
int xsgetn(char* s, int n);
virtual int sync();
protected: // See documentation in filebuf.C.
// virtual int pbackfail(int c);
int is_reading() { return eback() != egptr(); }
char* cur_ptr() { return is_reading() ? gptr() : pptr(); }
/* System's idea of pointer */
char* file_ptr() { return eGptr(); }
int do_write(const char *data, int to_do);
int do_flush() { return do_write(_pbase, _pptr-_pbase); }
// Low-level operations (Usually invoke system calls.)
virtual _G_ssize_t sys_read(char* buf, _G_size_t size);
virtual fpos_t sys_seek(fpos_t, _seek_dir);
virtual _G_ssize_t sys_write(const void*, long);
virtual int sys_stat(void*); // Actually, a (struct stat*)
virtual int sys_close();
};
inline ios::ios(streambuf* sb /* = 0 */, ostream* tie /* = 0 */) {
_state = sb ? ios::goodbit : ios::badbit; _exceptions=0;
_strbuf=sb; _tie = tie; _width=0; _fill=' ';
_flags=ios::skipws|ios::dec; _precision=6; }
inline ios::~ios() {
if (!(_flags & (unsigned int)ios::dont_close)) delete _strbuf; }
#endif /* _STREAMBUF_H */
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