glib/giochannel.h

   1 /* GLIB - Library of useful routines for C programming
   2  * Copyright (C) 1995-1997  Peter Mattis, Spencer Kimball and Josh MacDonald
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 /*
  19  * Modified by the GLib Team and others 1997-2000.  See the AUTHORS
  20  * file for a list of people on the GLib Team.  See the ChangeLog
  21  * files for a list of changes.  These files are distributed with
  22  * GLib at ftp://ftp.gtk.org/pub/gtk/.
  23  */
  24
  25 #ifndef __G_IOCHANNEL_H__
  26 #define __G_IOCHANNEL_H__
  27
  28 #if !defined (__GLIB_H_INSIDE__) && !defined (GLIB_COMPILATION)
  29 #error "Only <glib.h> can be included directly."
  30 #endif
  31
  32 #include <glib/gconvert.h>
  33 #include <glib/gmain.h>
  34 #include <glib/gstring.h>
  35
  36 G_BEGIN_DECLS
  37
  38 /* GIOChannel
  39  */
  40
  41 typedef struct _GIOChannel      GIOChannel;
  42 typedef struct _GIOFuncs        GIOFuncs;
  43
  44 typedef enum
  45 {
  46   G_IO_ERROR_NONE,
  47   G_IO_ERROR_AGAIN,
  48   G_IO_ERROR_INVAL,
  49   G_IO_ERROR_UNKNOWN
  50 } GIOError;
  51
  52 #define G_IO_CHANNEL_ERROR g_io_channel_error_quark()
  53
  54 typedef enum
  55 {
  56   /* Derived from errno */
  57   G_IO_CHANNEL_ERROR_FBIG,
  58   G_IO_CHANNEL_ERROR_INVAL,
  59   G_IO_CHANNEL_ERROR_IO,
  60   G_IO_CHANNEL_ERROR_ISDIR,
  61   G_IO_CHANNEL_ERROR_NOSPC,
  62   G_IO_CHANNEL_ERROR_NXIO,
  63   G_IO_CHANNEL_ERROR_OVERFLOW,
  64   G_IO_CHANNEL_ERROR_PIPE,
  65   /* Other */
  66   G_IO_CHANNEL_ERROR_FAILED
  67 } GIOChannelError;
  68
  69 typedef enum
  70 {
  71   G_IO_STATUS_ERROR,
  72   G_IO_STATUS_NORMAL,
  73   G_IO_STATUS_EOF,
  74   G_IO_STATUS_AGAIN
  75 } GIOStatus;
  76
  77 typedef enum
  78 {
  79   G_SEEK_CUR,
  80   G_SEEK_SET,
  81   G_SEEK_END
  82 } GSeekType;
  83
  84 typedef enum
  85 {
  86   G_IO_FLAG_APPEND = 1 << 0,
  87   G_IO_FLAG_NONBLOCK = 1 << 1,
  88   G_IO_FLAG_IS_READABLE = 1 << 2,       /* Read only flag */
  89   G_IO_FLAG_IS_WRITABLE = 1 << 3,       /* Read only flag */
  90   G_IO_FLAG_IS_WRITEABLE = 1 << 3,      /* Misspelling in 2.29.10 and earlier */
  91   G_IO_FLAG_IS_SEEKABLE = 1 << 4,       /* Read only flag */
  92   G_IO_FLAG_MASK = (1 << 5) - 1,
  93   G_IO_FLAG_GET_MASK = G_IO_FLAG_MASK,
  94   G_IO_FLAG_SET_MASK = G_IO_FLAG_APPEND | G_IO_FLAG_NONBLOCK
  95 } GIOFlags;
  96
  97 struct _GIOChannel
  98 {
  99   /*< private >*/
 100   gint ref_count;
 101   GIOFuncs *funcs;
 102
 103   gchar *encoding;
 104   GIConv read_cd;
 105   GIConv write_cd;
 106   gchar *line_term;             /* String which indicates the end of a line of text */
 107   guint line_term_len;          /* So we can have null in the line term */
 108
 109   gsize buf_size;
 110   GString *read_buf;            /* Raw data from the channel */
 111   GString *encoded_read_buf;    /* Channel data converted to UTF-8 */
 112   GString *write_buf;           /* Data ready to be written to the file */
 113   gchar partial_write_buf[6];   /* UTF-8 partial characters, null terminated */
 114
 115   /* Group the flags together, immediately after partial_write_buf, to save memory */
 116
 117   guint use_buffer     : 1;     /* The encoding uses the buffers */
 118   guint do_encode      : 1;     /* The encoding uses the GIConv coverters */
 119   guint close_on_unref : 1;     /* Close the channel on final unref */
 120   guint is_readable    : 1;     /* Cached GIOFlag */
 121   guint is_writeable   : 1;     /* ditto */
 122   guint is_seekable    : 1;     /* ditto */
 123
 124   gpointer reserved1;
 125   gpointer reserved2;
 126 };
 127
 128 typedef gboolean (*GIOFunc) (GIOChannel   *source,
 129                              GIOCondition  condition,
 130                              gpointer      data);
 131 struct _GIOFuncs
 132 {
 133   GIOStatus (*io_read)           (GIOChannel   *channel,
 134                                   gchar        *buf,
 135                                   gsize         count,
 136                                   gsize        *bytes_read,
 137                                   GError      **err);
 138   GIOStatus (*io_write)          (GIOChannel   *channel,
 139                                   const gchar  *buf,
 140                                   gsize         count,
 141                                   gsize        *bytes_written,
 142                                   GError      **err);
 143   GIOStatus (*io_seek)           (GIOChannel   *channel,
 144                                   gint64        offset,
 145                                   GSeekType     type,
 146                                   GError      **err);
 147   GIOStatus  (*io_close)         (GIOChannel   *channel,
 148                                   GError      **err);
 149   GSource*   (*io_create_watch)  (GIOChannel   *channel,
 150                                   GIOCondition  condition);
 151   void       (*io_free)          (GIOChannel   *channel);
 152   GIOStatus  (*io_set_flags)     (GIOChannel   *channel,
 153                                   GIOFlags      flags,
 154                                   GError      **err);
 155   GIOFlags   (*io_get_flags)     (GIOChannel   *channel);
 156 };
 157
 158 GLIB_AVAILABLE_IN_ALL
 159 void        g_io_channel_init   (GIOChannel    *channel);
 160 GLIB_AVAILABLE_IN_ALL
 161 GIOChannel *g_io_channel_ref    (GIOChannel    *channel);
 162 GLIB_AVAILABLE_IN_ALL
 163 void        g_io_channel_unref  (GIOChannel    *channel);
 164
 165 GLIB_DEPRECATED_FOR(g_io_channel_read_chars)
 166 GIOError    g_io_channel_read   (GIOChannel    *channel,
 167                                  gchar         *buf,
 168                                  gsize          count,
 169                                  gsize         *bytes_read);
 170
 171 GLIB_DEPRECATED_FOR(g_io_channel_write_chars)
 172 GIOError  g_io_channel_write    (GIOChannel    *channel,
 173                                  const gchar   *buf,
 174                                  gsize          count,
 175                                  gsize         *bytes_written);
 176
 177 GLIB_DEPRECATED_FOR(g_io_channel_seek_position)
 178 GIOError  g_io_channel_seek     (GIOChannel    *channel,
 179                                  gint64         offset,
 180                                  GSeekType      type);
 181
 182 GLIB_DEPRECATED_FOR(g_io_channel_shutdown)
 183 void      g_io_channel_close    (GIOChannel    *channel);
 184
 185 GLIB_AVAILABLE_IN_ALL
 186 GIOStatus g_io_channel_shutdown (GIOChannel      *channel,
 187                                  gboolean         flush,
 188                                  GError         **err);
 189 GLIB_AVAILABLE_IN_ALL
 190 guint     g_io_add_watch_full   (GIOChannel      *channel,
 191                                  gint             priority,
 192                                  GIOCondition     condition,
 193                                  GIOFunc          func,
 194                                  gpointer         user_data,
 195                                  GDestroyNotify   notify);
 196 GLIB_AVAILABLE_IN_ALL
 197 GSource * g_io_create_watch     (GIOChannel      *channel,
 198                                  GIOCondition     condition);
 199 GLIB_AVAILABLE_IN_ALL
 200 guint     g_io_add_watch        (GIOChannel      *channel,
 201                                  GIOCondition     condition,
 202                                  GIOFunc          func,
 203                                  gpointer         user_data);
 204
 205 /* character encoding conversion involved functions.
 206  */
 207
 208 GLIB_AVAILABLE_IN_ALL
 209 void                  g_io_channel_set_buffer_size      (GIOChannel   *channel,
 210                                                          gsize         size);
 211 GLIB_AVAILABLE_IN_ALL
 212 gsize                 g_io_channel_get_buffer_size      (GIOChannel   *channel);
 213 GLIB_AVAILABLE_IN_ALL
 214 GIOCondition          g_io_channel_get_buffer_condition (GIOChannel   *channel);
 215 GLIB_AVAILABLE_IN_ALL
 216 GIOStatus             g_io_channel_set_flags            (GIOChannel   *channel,
 217                                                          GIOFlags      flags,
 218                                                          GError      **error);
 219 GLIB_AVAILABLE_IN_ALL
 220 GIOFlags              g_io_channel_get_flags            (GIOChannel   *channel);
 221 GLIB_AVAILABLE_IN_ALL
 222 void                  g_io_channel_set_line_term        (GIOChannel   *channel,
 223                                                          const gchar  *line_term,
 224                                                          gint          length);
 225 GLIB_AVAILABLE_IN_ALL
 226 const gchar *         g_io_channel_get_line_term        (GIOChannel   *channel,
 227                                                          gint         *length);
 228 GLIB_AVAILABLE_IN_ALL
 229 void                  g_io_channel_set_buffered         (GIOChannel   *channel,
 230                                                          gboolean      buffered);
 231 GLIB_AVAILABLE_IN_ALL
 232 gboolean              g_io_channel_get_buffered         (GIOChannel   *channel);
 233 GLIB_AVAILABLE_IN_ALL
 234 GIOStatus             g_io_channel_set_encoding         (GIOChannel   *channel,
 235                                                          const gchar  *encoding,
 236                                                          GError      **error);
 237 GLIB_AVAILABLE_IN_ALL
 238 const gchar *         g_io_channel_get_encoding         (GIOChannel   *channel);
 239 GLIB_AVAILABLE_IN_ALL
 240 void                  g_io_channel_set_close_on_unref   (GIOChannel   *channel,
 241                                                          gboolean      do_close);
 242 GLIB_AVAILABLE_IN_ALL
 243 gboolean              g_io_channel_get_close_on_unref   (GIOChannel   *channel);
 244
 245
 246 GLIB_AVAILABLE_IN_ALL
 247 GIOStatus   g_io_channel_flush            (GIOChannel   *channel,
 248                                            GError      **error);
 249 GLIB_AVAILABLE_IN_ALL
 250 GIOStatus   g_io_channel_read_line        (GIOChannel   *channel,
 251                                            gchar       **str_return,
 252                                            gsize        *length,
 253                                            gsize        *terminator_pos,
 254                                            GError      **error);
 255 GLIB_AVAILABLE_IN_ALL
 256 GIOStatus   g_io_channel_read_line_string (GIOChannel   *channel,
 257                                            GString      *buffer,
 258                                            gsize        *terminator_pos,
 259                                            GError      **error);
 260 GLIB_AVAILABLE_IN_ALL
 261 GIOStatus   g_io_channel_read_to_end      (GIOChannel   *channel,
 262                                            gchar       **str_return,
 263                                            gsize        *length,
 264                                            GError      **error);
 265 GLIB_AVAILABLE_IN_ALL
 266 GIOStatus   g_io_channel_read_chars       (GIOChannel   *channel,
 267                                            gchar        *buf,
 268                                            gsize         count,
 269                                            gsize        *bytes_read,
 270                                            GError      **error);
 271 GLIB_AVAILABLE_IN_ALL
 272 GIOStatus   g_io_channel_read_unichar     (GIOChannel   *channel,
 273                                            gunichar     *thechar,
 274                                            GError      **error);
 275 GLIB_AVAILABLE_IN_ALL
 276 GIOStatus   g_io_channel_write_chars      (GIOChannel   *channel,
 277                                            const gchar  *buf,
 278                                            gssize        count,
 279                                            gsize        *bytes_written,
 280                                            GError      **error);
 281 GLIB_AVAILABLE_IN_ALL
 282 GIOStatus   g_io_channel_write_unichar    (GIOChannel   *channel,
 283                                            gunichar      thechar,
 284                                            GError      **error);
 285 GLIB_AVAILABLE_IN_ALL
 286 GIOStatus   g_io_channel_seek_position    (GIOChannel   *channel,
 287                                            gint64        offset,
 288                                            GSeekType     type,
 289                                            GError      **error);
 290 GLIB_AVAILABLE_IN_ALL
 291 GIOChannel* g_io_channel_new_file         (const gchar  *filename,
 292                                            const gchar  *mode,
 293                                            GError      **error);
 294
 295 /* Error handling */
 296
 297 GLIB_AVAILABLE_IN_ALL
 298 GQuark          g_io_channel_error_quark      (void);
 299 GLIB_AVAILABLE_IN_ALL
 300 GIOChannelError g_io_channel_error_from_errno (gint en);
 301
 302 /* On Unix, IO channels created with this function for any file
 303  * descriptor or socket.
 304  *
 305  * On Win32, this can be used either for files opened with the MSVCRT
 306  * (the Microsoft run-time C library) _open() or _pipe, including file
 307  * descriptors 0, 1 and 2 (corresponding to stdin, stdout and stderr),
 308  * or for Winsock SOCKETs. If the parameter is a legal file
 309  * descriptor, it is assumed to be such, otherwise it should be a
 310  * SOCKET. This relies on SOCKETs and file descriptors not
 311  * overlapping. If you want to be certain, call either
 312  * g_io_channel_win32_new_fd() or g_io_channel_win32_new_socket()
 313  * instead as appropriate.
 314  *
 315  * The term file descriptor as used in the context of Win32 refers to
 316  * the emulated Unix-like file descriptors MSVCRT provides. The native
 317  * corresponding concept is file HANDLE. There isn't as of yet a way to
 318  * get GIOChannels for Win32 file HANDLEs.
 319  */
 320 GLIB_AVAILABLE_IN_ALL
 321 GIOChannel* g_io_channel_unix_new    (int         fd);
 322 GLIB_AVAILABLE_IN_ALL
 323 gint        g_io_channel_unix_get_fd (GIOChannel *channel);
 324
 325
 326 /* Hook for GClosure / GSource integration. Don't touch */
 327 GLIB_VAR GSourceFuncs g_io_watch_funcs;
 328
 329 #ifdef G_OS_WIN32
 330
 331 /* You can use this "pseudo file descriptor" in a GPollFD to add
 332  * polling for Windows messages. GTK applications should not do that.
 333  */
 334
 335 #define G_WIN32_MSG_HANDLE 19981206
 336
 337 /* Use this to get a GPollFD from a GIOChannel, so that you can call
 338  * g_io_channel_win32_poll(). After calling this you should only use
 339  * g_io_channel_read() to read from the GIOChannel, i.e. never read()
 340  * from the underlying file descriptor. For SOCKETs, it is possible to call
 341  * recv().
 342  */
 343 GLIB_AVAILABLE_IN_ALL
 344 void        g_io_channel_win32_make_pollfd (GIOChannel   *channel,
 345                                             GIOCondition  condition,
 346                                             GPollFD      *fd);
 347
 348 /* This can be used to wait a until at least one of the channels is readable.
 349  * On Unix you would do a select() on the file descriptors of the channels.
 350  */
 351 GLIB_AVAILABLE_IN_ALL
 352 gint        g_io_channel_win32_poll   (GPollFD    *fds,
 353                                        gint        n_fds,
 354                                        gint        timeout_);
 355
 356 /* Create an IO channel for Windows messages for window handle hwnd. */
 357 #if GLIB_SIZEOF_VOID_P == 8
 358 /* We use gsize here so that it is still an integer type and not a
 359  * pointer, like the guint in the traditional prototype. We can't use
 360  * intptr_t as that is not portable enough.
 361  */
 362 GLIB_AVAILABLE_IN_ALL
 363 GIOChannel *g_io_channel_win32_new_messages (gsize hwnd);
 364 #else
 365 GLIB_AVAILABLE_IN_ALL
 366 GIOChannel *g_io_channel_win32_new_messages (guint hwnd);
 367 #endif
 368
 369 /* Create an IO channel for C runtime (emulated Unix-like) file
 370  * descriptors. After calling g_io_add_watch() on a IO channel
 371  * returned by this function, you shouldn't call read() on the file
 372  * descriptor. This is because adding polling for a file descriptor is
 373  * implemented on Win32 by starting a thread that sits blocked in a
 374  * read() from the file descriptor most of the time. All reads from
 375  * the file descriptor should be done by this internal GLib
 376  * thread. Your code should call only g_io_channel_read_chars().
 377  */
 378 GLIB_AVAILABLE_IN_ALL
 379 GIOChannel* g_io_channel_win32_new_fd (gint         fd);
 380
 381 /* Get the C runtime file descriptor of a channel. */
 382 GLIB_AVAILABLE_IN_ALL
 383 gint        g_io_channel_win32_get_fd (GIOChannel *channel);
 384
 385 /* Create an IO channel for a winsock socket. The parameter should be
 386  * a SOCKET. Contrary to IO channels for file descriptors (on *Win32),
 387  * you can use normal recv() or recvfrom() on sockets even if GLib
 388  * is polling them.
 389  */
 390 GLIB_AVAILABLE_IN_ALL
 391 GIOChannel *g_io_channel_win32_new_socket (gint socket);
 392
 393 GLIB_DEPRECATED_FOR(g_io_channel_win32_new_socket)
 394 GIOChannel *g_io_channel_win32_new_stream_socket (gint socket);
 395
 396 GLIB_AVAILABLE_IN_ALL
 397 void        g_io_channel_win32_set_debug (GIOChannel *channel,
 398                                           gboolean    flag);
 399
 400 #endif
 401
 402 #ifndef __GTK_DOC_IGNORE__
 403 #ifdef G_OS_WIN32
 404 #define g_io_channel_new_file g_io_channel_new_file_utf8
 405
 406 GLIB_AVAILABLE_IN_ALL
 407 GIOChannel *g_io_channel_new_file_utf8 (const gchar  *filename,
 408                                         const gchar  *mode,
 409                                         GError      **error);
 410 #endif
 411 #endif /* __GTK_DOC_IGNORE__ */
 412
 413 G_END_DECLS
 414
 415 #endif /* __G_IOCHANNEL_H__ */