ACE/ace/IOStream.h

   1 // -*- C++ -*-
   2
   3 //=============================================================================
   4 /**
   5  *  @file    IOStream.h
   6  *
   7  *  @author James CE Johnson <jcej@lads.com>
   8  *  @author Jim Crossley <jim@lads.com>
   9  */
  10 //=============================================================================
  11
  12 #ifndef ACE_IOSTREAM_H
  13 #define ACE_IOSTREAM_H
  14 #include /**/ "ace/pre.h"
  15
  16 #include /**/ "ace/ACE_export.h"
  17
  18 #if !defined (ACE_LACKS_PRAGMA_ONCE)
  19 # pragma once
  20 #endif /* ACE_LACKS_PRAGMA_ONCE */
  21
  22 // Needed on Windows for streambuf
  23 // FUZZ: disable check_for_streams_include
  24 #include "ace/streams.h"
  25
  26 // This is a temporary restriction - ACE_IOStream is only enabled if the
  27 // compiler does not supply the standard C++ library (and standard iostreams)
  28 // or, if it does, the platform is explicitly set to use old iostreams
  29 // by its config.h file.
  30 // This restriction is recorded in Bugzilla entry 857.
  31 #if defined (ACE_HAS_STANDARD_CPP_LIBRARY) && (ACE_HAS_STANDARD_CPP_LIBRARY == 1)
  32 #  if !defined (ACE_USES_OLD_IOSTREAMS) && !defined (ACE_LACKS_ACE_IOSTREAM)
  33 #    define ACE_LACKS_ACE_IOSTREAM
  34 #  endif /* !ACE_USES_OLD_IOSTREAMS && !ACE_LACKS_ACE_IOSTREAM */
  35 #endif /* ACE_HAS_STANDARD_CPP_LIBRARY */
  36
  37 #if !defined (ACE_LACKS_ACE_IOSTREAM)
  38
  39 #  if defined (ACE_HAS_STRING_CLASS)
  40 #    if defined (ACE_WIN32) && defined (_MSC_VER)
  41 ACE_BEGIN_VERSIONED_NAMESPACE_DECL
  42 typedef CString ACE_IOStream_String;
  43 ACE_END_VERSIONED_NAMESPACE_DECL
  44 #    else
  45 #      if !defined (ACE_HAS_STDCPP_STL_INCLUDES)
  46 #include /**/ <String.h>
  47 ACE_BEGIN_VERSIONED_NAMESPACE_DECL
  48 typedef String ACE_IOStream_String;
  49 ACE_END_VERSIONED_NAMESPACE_DECL
  50 #      else
  51 #        include /**/ <string>
  52
  53 #        if defined(ACE_USES_STD_NAMESPACE_FOR_STDCPP_LIB)
  54 ACE_BEGIN_VERSIONED_NAMESPACE_DECL
  55 typedef std::string ACE_IOStream_String;
  56 ACE_END_VERSIONED_NAMESPACE_DECL
  57 #        else
  58 ACE_BEGIN_VERSIONED_NAMESPACE_DECL
  59 typedef string ACE_IOStream_String;
  60 ACE_END_VERSIONED_NAMESPACE_DECL
  61 #        endif /* ACE_USES_STD_NAMESPACE_FOR_STDCPP_LIB */
  62 #      endif /* ! ACE_HAS_STDCPP_STL_INCLUDES */
  63 #    endif /* ACE_WIN32 && defined (_MSC_VER) */
  64
  65 ACE_BEGIN_VERSIONED_NAMESPACE_DECL
  66
  67 class ACE_Export ACE_Quoted_String : public ACE_IOStream_String
  68 {
  69 public:
  70   inline ACE_Quoted_String (void) { *this = ""; }
  71   inline ACE_Quoted_String (const char *c) { *this = ACE_IOStream_String (c); }
  72   inline ACE_Quoted_String (const ACE_IOStream_String &s) { *this = s; }
  73   inline ACE_Quoted_String &operator= (const ACE_IOStream_String& s)
  74   {
  75     return (ACE_Quoted_String &) ACE_IOStream_String::operator= (s);
  76   }
  77   inline ACE_Quoted_String &operator = (const char c) {
  78     return (ACE_Quoted_String &) ACE_IOStream_String::operator= (c);
  79   }
  80   inline ACE_Quoted_String &operator = (const char *c) {
  81     return (ACE_Quoted_String &) ACE_IOStream_String::operator= (c);
  82   }
  83   inline bool operator < (const ACE_Quoted_String &s) const {
  84     return *(ACE_IOStream_String *) this < (ACE_IOStream_String) s;
  85   }
  86 #    if defined (ACE_WIN32) && defined (_MSC_VER)
  87   inline int length (void) { return this->GetLength (); }
  88 #    endif /* ACE_WIN32 && defined (_MSC_VER) */
  89 };
  90
  91 ACE_END_VERSIONED_NAMESPACE_DECL
  92
  93 #  endif /* ACE_HAS_STRING_CLASS */
  94
  95 #  include "ace/Time_Value.h"
  96 #  include "ace/os_include/sys/os_types.h"
  97
  98 ACE_BEGIN_VERSIONED_NAMESPACE_DECL
  99
 100 /**
 101  * @class ACE_Streambuf
 102  *
 103  * @brief Create your custom streambuf by providing and ACE_*_Stream
 104  * object to this template.  I have tested it with
 105  * ACE_SOCK_Stream and it should work fine for others as well.
 106  *
 107  * For any iostream object, the real work is done by the
 108  * underlying streambuf class.  That is what we create here.
 109  * A streambuf has an internal buffer area into which data is
 110  * read and written as the iostream requests and provides data.
 111  * At some point during the read process, the iostream will
 112  * realize that the streambuf has no more data.  The underflow
 113  * function of the streambuf is then called.
 114  * Likewise, during the write process, the iostream will
 115  * eventually notice that the streabuf's buffer has become full
 116  * and will invoke the overflow function.
 117  * The empty/full state of the read/write "buffers" are
 118  * controled by two sets pointers.  One set is dedicated to
 119  * read, the other to write.  These pointers, in turn, reference
 120  * a common buffer that is to be shared by both read and write
 121  * operations.  It is this common buffer to which data is
 122  * written and from which it is read.
 123  * The common buffer is used by functions of the streambuf as
 124  * well as the iostream.  Because of this and the fact that it
 125  * is "shared" by both read and write operators, there is a
 126  * danger of data corruption if read and write operations are
 127  * allowed to take place "at the same time".
 128  * To prevent data corruption, we manipulate the read and write
 129  * pointer sets so that the streambuf is in either a read-mode
 130  * or write-mode at all times and can never be in both modes at
 131  * the same time.
 132  * In the constructor: set the read and write sets to NULL This
 133  * causes the underflow or overflow operators to be invoked at
 134  * the first IO activity of the iostream.
 135  * In the underflow function we arrange for the common buffer to
 136  * reference our read buffer and for the write pointer set to be
 137  * disabled.  If a write operation is performed by the iostream
 138  * this will cause the overflow function to be invoked.
 139  * In the overflow function we arrange for the common buffer to
 140  * reference our write buffer and for the read pointer set to be
 141  * disabled.  This causes the underflow function to be invoked
 142  * when the iostream "changes our mode".
 143  * The overflow function will also invoke the send_n function to
 144  * flush the buffered data to our peer.  Similarly, the sync and
 145  * syncout functions will cause send_n to be invoked to send the
 146  * data.
 147  * Since socket's and the like do not support seeking, there can
 148  * be no method for "syncing" the input.  However, since we
 149  * maintain separate read/write buffers, no data is lost by
 150  * "syncing" the input.  It simply remains buffered.
 151  */
 152 class ACE_Export ACE_Streambuf : public streambuf
 153 {
 154 public:
 155
 156   /**
 157    * If the default allocation strategy were used the common buffer
 158    * would be deleted when the object destructs.  Since we are
 159    * providing separate read/write buffers, it is up to us to manage
 160    * their memory.
 161    */
 162   virtual ~ACE_Streambuf (void);
 163
 164   /// Get the current Time_Value pointer and provide a new one.
 165   ACE_Time_Value *recv_timeout (ACE_Time_Value *tv = 0);
 166
 167   /**
 168    * Use this to allocate a new/different buffer for put operations.
 169    * If you do not provide a buffer pointer, one will be allocated.
 170    * That is the preferred method.  If you do provide a buffer, the
 171    * size must match that being used by the get buffer.  If
 172    * successful, you will receive a pointer to the current put buffer.
 173    * It is your responsibility to delete this memory when you are done
 174    * with it.
 175    */
 176   char *reset_put_buffer (char *newBuffer = 0,
 177                           u_int _streambuf_size = 0,
 178                           u_int _pptr = 0 );
 179
 180   /// Return the number of bytes to be 'put' onto the stream media.
 181   ///    pbase + put_avail = pptr
 182   u_int put_avail (void);
 183
 184   /**
 185    * Use this to allocate a new/different buffer for get operations.
 186    * If you do not provide a buffer pointer, one will be allocated.
 187    * That is the preferred method.  If you do provide a buffer, the
 188    * size must match that being used by the put buffer.  If
 189    * successful, you will receive a pointer to the current get buffer.
 190    * It is your responsibility to delete this memory when you are done
 191    * with it.
 192    */
 193   char *reset_get_buffer (char *newBuffer = 0,
 194                           u_int _streambuf_size = 0,
 195                           u_int _gptr = 0,
 196                           u_int _egptr = 0);
 197
 198   /// Return the number of bytes not yet gotten.  eback + get_waiting =
 199   /// gptr
 200   u_int get_waiting (void);
 201
 202   /// Return the number of bytes in the get area (includes some already
 203   /// gotten); eback + get_avail = egptr
 204   u_int get_avail (void);
 205
 206   /// Query the streambuf for the size of its buffers.
 207   u_int streambuf_size (void);
 208
 209   /// Did we take an error because of an IO operation timeout?
 210   /// @note Invoking this resets the flag.
 211   u_char timeout (void);
 212
 213 protected:
 214   ACE_Streambuf (u_int streambuf_size,
 215                  int io_mode);
 216
 217   /// Sync both input and output. See syncin/syncout below for
 218   /// descriptions.
 219   virtual int sync (void);
 220
 221   // = Signatures for the underflow/overflow discussed above.
 222   virtual int underflow (void);
 223
 224   /// The overflow function receives the character which caused the
 225   /// overflow.
 226   virtual int overflow (int c = EOF);
 227
 228   /// Resets the <base> pointer and streambuf mode.  This is used
 229   /// internally when get/put buffers are allocatd.
 230   void reset_base (void);
 231
 232 protected:
 233   // = Two pointer sets for manipulating the read/write areas.
 234   char *eback_saved_;
 235   char *gptr_saved_;
 236   char *egptr_saved_;
 237   char *pbase_saved_;
 238   char *pptr_saved_;
 239   char *epptr_saved_;
 240
 241   // = With cur_mode_ we keep track of our current IO mode.
 242
 243   // This helps us to optimize the underflow/overflow functions.
 244   u_char cur_mode_;
 245   const u_char get_mode_;
 246   const u_char put_mode_;
 247
 248   /// mode tells us if we're working for an istream, ostream, or
 249   /// iostream.
 250   int mode_;
 251
 252   /// This defines the size of the input and output buffers.  It can be
 253   /// set by the object constructor.
 254   const u_int streambuf_size_;
 255
 256   /// Did we take an error because of an IO operation timeout?
 257   u_char timeout_;
 258
 259   /// We want to allow the user to provide Time_Value pointers to
 260   /// prevent infinite blocking while waiting to receive data.
 261   ACE_Time_Value recv_timeout_value_;
 262   ACE_Time_Value *recv_timeout_;
 263
 264   /**
 265    * syncin is called when the input needs to be synced with the
 266    * source file.  In a filebuf, this results in the <seek> system
 267    * call being used.  We can't do that on socket-like connections, so
 268    * this does basically nothing.  That's safe because we have a
 269    * separate read buffer to maintain the already-read data.  In a
 270    * filebuf, the single common buffer is used forcing the <seek>
 271    * call.
 272    */
 273   int syncin (void);
 274
 275   /// syncout() is called when the output needs to be flushed.  This is
 276   /// easily done by calling the peer's send_n function.
 277   int syncout (void);
 278
 279   /// flushbuf() is the worker of syncout.  It is a separate function
 280   /// because it gets used sometimes in different context.
 281   int flushbuf (void);
 282
 283   /**
 284    * fillbuf is called in a couple of places.  This is the worker of
 285    * underflow.  It will attempt to fill the read buffer from the
 286    * peer.
 287    */
 288   int fillbuf (void);
 289
 290   /**
 291    * Used by fillbuf and others to get exactly one byte from the peer.
 292    * recv_n is used to be sure we block until something is available.
 293    * It is virtual because we really need to override it for
 294    * datagram-derived objects.
 295    */
 296   virtual int get_one_byte (void);
 297
 298   /**
 299    * Stream connections and "unconnected connections" (ie --
 300    * datagrams) need to work just a little differently.  We derive
 301    * custom Streambuf objects for them and provide these functions at
 302    * that time.
 303    */
 304   virtual ssize_t send (char *buf,
 305                         ssize_t len) = 0;
 306   virtual ssize_t recv (char *buf,
 307                         ssize_t len,
 308                         ACE_Time_Value *tv = 0) = 0;
 309   virtual ssize_t recv (char *buf,
 310                         ssize_t len,
 311                         int flags,
 312                         ACE_Time_Value *tv = 0) = 0;
 313   virtual ssize_t recv_n (char *buf,
 314                           ssize_t len,
 315                           int flags = 0,
 316                           ACE_Time_Value *tv = 0) = 0;
 317
 318   virtual ACE_HANDLE get_handle (void);
 319
 320 #  if defined (ACE_HAS_STANDARD_CPP_LIBRARY) && (ACE_HAS_STANDARD_CPP_LIBRARY != 0) && !defined (ACE_USES_OLD_IOSTREAMS)
 321   char *base (void) const
 322     {
 323       return cur_mode_ == get_mode_ ? eback_saved_
 324         : cur_mode_ == put_mode_ ? pbase_saved_
 325         : 0;
 326     }
 327   char *ebuf (void) const
 328     {
 329       return cur_mode_ == 0 ? 0 : base () + streambuf_size_;
 330     }
 331
 332   int blen (void) const
 333     {
 334       return streambuf_size_;
 335     }
 336
 337   void setb (char* b, char* eb, int /* a */=0)
 338     {
 339       setbuf (b, (eb - b));
 340     }
 341
 342   int out_waiting (void)
 343     {
 344       return pptr () - pbase ();
 345     }
 346 #  endif /* ACE_HAS_STANDARD_CPP_LIBRARY */
 347 };
 348
 349 ACE_END_VERSIONED_NAMESPACE_DECL
 350
 351 ///////////////////////////////////////////////////////////////////////////
 352
 353 // These typedefs are provided by G++ (on some systems?) without the
 354 // trailing '_'.  Since we can't count on 'em, I've defined them to
 355 // what GNU wants here.
 356 //
 357 typedef ios& (*__manip_)(ios&);
 358 typedef istream& (*__imanip_)(istream&);
 359 typedef ostream& (*__omanip_)(ostream&);
 360
 361 // Trying to do something like is shown below instead of using the
 362 // __*manip typedefs causes Linux do segfault when "<<endl" is done.
 363 //
 364 //        virtual MT& operator<<(ios& (*func)(ios&))  { (*func)(*this); return *this; }
 365
 366 // This macro defines the get operator for class MT into datatype DT.
 367 // We will use it below to quickly override most (all?)  iostream get
 368 // operators.  Notice how the <ipfx> and <isfx> functions are used.
 369
 370 #define GET_SIG(MT,DT)          inline virtual MT& operator>> (DT v)
 371 #  if (defined (__SUNPRO_CC) && __SUNPRO_CC > 0x510)
 372 #define GET_CODE {                      \
 373         if (ipfx (0))                                   \
 374         {                                               \
 375                 (*((istream*)this)) >> (v);             \
 376         }                                               \
 377         isfx ();                                        \
 378         return *this;                                   \
 379         }
 380 #  else
 381 #define GET_CODE {                      \
 382         if (ipfx (0))                                   \
 383         {                                               \
 384                 iostream::operator>> (v);               \
 385         }                                               \
 386         isfx ();                                        \
 387         return *this;                                   \
 388         }
 389 #  endif
 390 #define GET_PROT(MT,DT,CODE)    GET_SIG(MT,DT)  CODE
 391 #define GET_FUNC(MT,DT)         GET_PROT(MT,DT,GET_CODE)
 392
 393 // This macro defines the put operator for class MT into datatype DT.
 394 // We will use it below to quickly override most (all?)  iostream put
 395 // operators.  Notice how the <opfx> and <osfx> functions are used.
 396
 397 #define PUT_SIG(MT,DT)          inline virtual MT& operator<< (DT v)
 398 #  if (defined (__SUNPRO_CC) && __SUNPRO_CC > 0x510)
 399 #define PUT_CODE {                      \
 400         if (opfx ())                                    \
 401         {                                               \
 402                 (*((ostream *) this)) << (v);            \
 403         }                                               \
 404         osfx ();                                        \
 405         return *this;                                   \
 406         }
 407 #  else
 408 #define PUT_CODE {                      \
 409         if (opfx ())                                    \
 410         {                                               \
 411                 iostream::operator<< (v);               \
 412         }                                               \
 413         osfx ();                                        \
 414         return *this;                                   \
 415         }
 416 #  endif
 417 #define PUT_PROT(MT,DT,CODE)    PUT_SIG(MT,DT)  CODE
 418 #define PUT_FUNC(MT,DT)         PUT_PROT(MT,DT,PUT_CODE)
 419
 420
 421 // These are necessary in case somebody wants to derive from us and
 422 // override one of these with a custom approach.
 423
 424 #  if defined (ACE_LACKS_CHAR_RIGHT_SHIFTS)
 425 #define GET_FUNC_SET0(MT,CODE,CODE2) \
 426         GET_PROT(MT,short &,CODE) \
 427         GET_PROT(MT,u_short &,CODE) \
 428         GET_PROT(MT,int &,CODE) \
 429         GET_PROT(MT,u_int &,CODE) \
 430         GET_PROT(MT,long &,CODE) \
 431         GET_PROT(MT,u_long &,CODE) \
 432         GET_PROT(MT,float &,CODE) \
 433         GET_PROT(MT,double &,CODE) \
 434         inline virtual MT& operator>>(__omanip_ func) CODE2 \
 435         inline virtual MT& operator>>(__manip_ func)  CODE2
 436 #  else
 437 #define GET_FUNC_SET0(MT,CODE,CODE2) \
 438         GET_PROT(MT,short &,CODE) \
 439         GET_PROT(MT,u_short &,CODE) \
 440         GET_PROT(MT,int &,CODE) \
 441         GET_PROT(MT,u_int &,CODE) \
 442         GET_PROT(MT,long &,CODE) \
 443         GET_PROT(MT,u_long &,CODE) \
 444         GET_PROT(MT,float &,CODE) \
 445         GET_PROT(MT,double &,CODE) \
 446         GET_PROT(MT,char &,CODE) \
 447         GET_PROT(MT,u_char &,CODE) \
 448         GET_PROT(MT,char *,CODE) \
 449         GET_PROT(MT,u_char *,CODE) \
 450         inline virtual MT& operator>>(__omanip_ func) CODE2 \
 451         inline virtual MT& operator>>(__manip_ func)  CODE2
 452 #  endif
 453
 454 #define PUT_FUNC_SET0(MT,CODE,CODE2) \
 455         PUT_PROT(MT,short,CODE) \
 456         PUT_PROT(MT,u_short,CODE) \
 457         PUT_PROT(MT,int,CODE) \
 458         PUT_PROT(MT,u_int,CODE) \
 459         PUT_PROT(MT,long,CODE) \
 460         PUT_PROT(MT,u_long,CODE) \
 461         PUT_PROT(MT,float,CODE) \
 462         PUT_PROT(MT,double,CODE) \
 463         PUT_PROT(MT,char,CODE) \
 464         PUT_PROT(MT,u_char,CODE) \
 465         PUT_PROT(MT,const char *,CODE) \
 466         PUT_PROT(MT,u_char *,CODE) \
 467         PUT_PROT(MT,void *,CODE) \
 468         inline virtual MT& operator<<(__omanip_ func) CODE2 \
 469         inline virtual MT& operator<<(__manip_ func)  CODE2
 470
 471 #  if defined (ACE_LACKS_SIGNED_CHAR)
 472   #define GET_FUNC_SET1(MT,CODE,CODE2) GET_FUNC_SET0(MT,CODE,CODE2)
 473   #define PUT_FUNC_SET1(MT,CODE,CODE2) PUT_FUNC_SET0(MT,CODE,CODE2)
 474 #  else
 475   #define GET_FUNC_SET1(MT,CODE,CODE2) \
 476           GET_PROT(MT,signed char &,CODE) \
 477           GET_PROT(MT,signed char *,CODE) \
 478           GET_FUNC_SET0(MT,CODE,CODE2)
 479
 480   #define PUT_FUNC_SET1(MT,CODE,CODE2) \
 481           PUT_FUNC(MT,signed char) \
 482           PUT_FUNC(MT,const signed char *) \
 483           PUT_FUNC_SET0(MT,CODE,CODE2)
 484 #  endif /* ACE_LACKS_SIGNED_CHAR */
 485
 486 #define GET_MANIP_CODE  { if (ipfx ()) { (*func) (*this); } isfx (); return *this; }
 487 #define PUT_MANIP_CODE  { if (opfx ()) { (*func) (*this); } osfx (); return *this; }
 488
 489 #define GET_FUNC_SET(MT)        GET_FUNC_SET1(MT,GET_CODE,GET_MANIP_CODE)
 490 #define PUT_FUNC_SET(MT)        PUT_FUNC_SET1(MT,PUT_CODE,PUT_MANIP_CODE)
 491 #define GETPUT_FUNC_SET(MT)     GET_FUNC_SET(MT) PUT_FUNC_SET(MT)
 492
 493 #define GET_SIG_SET(MT)         GET_FUNC_SET1(MT,= 0;,= 0;)
 494 #define PUT_SIG_SET(MT)         PUT_FUNC_SET1(MT,= 0;,= 0;)
 495 #define GETPUT_SIG_SET(MT)      GET_SIG_SET(MT) PUT_SIG_SET(MT)
 496
 497 // Include the templates here.
 498 #  include "ace/IOStream_T.h"
 499 #endif /* !ACE_LACKS_ACE_IOSTREAM && ACE_USES_OLD_IOSTREAMS */
 500
 501 #include /**/ "ace/post.h"
 502 #endif /* ACE_IOSTREAM_H */