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, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 /*
  21  * Modified by the GLib Team and others 1997-2000.  See the AUTHORS
  22  * file for a list of people on the GLib Team.  See the ChangeLog
  23  * files for a list of changes.  These files are distributed with
  24  * GLib at ftp://ftp.gtk.org/pub/gtk/.
  25  */
  26
  27 #ifndef __G_IOCHANNEL_H__
  28 #define __G_IOCHANNEL_H__
  29
  30 #if !defined (__GLIB_H_INSIDE__) && !defined (GLIB_COMPILATION)
  31 #error "Only <glib.h> can be included directly."
  32 #endif
  33
  34 #include <glib/gconvert.h>
  35 #include <glib/gmain.h>
  36 #include <glib/gstring.h>
  37
  38 G_BEGIN_DECLS
  39
  40 /* GIOChannel
  41  */
  42
  43 typedef struct _GIOChannel      GIOChannel;
  44 typedef struct _GIOFuncs        GIOFuncs;
  45
  46 typedef enum
  47 {
  48   G_IO_ERROR_NONE,
  49   G_IO_ERROR_AGAIN,
  50   G_IO_ERROR_INVAL,
  51   G_IO_ERROR_UNKNOWN
  52 } GIOError;
  53
  54 #define G_IO_CHANNEL_ERROR g_io_channel_error_quark()
  55
  56 typedef enum
  57 {
  58   /* Derived from errno */
  59   G_IO_CHANNEL_ERROR_FBIG,
  60   G_IO_CHANNEL_ERROR_INVAL,
  61   G_IO_CHANNEL_ERROR_IO,
  62   G_IO_CHANNEL_ERROR_ISDIR,
  63   G_IO_CHANNEL_ERROR_NOSPC,
  64   G_IO_CHANNEL_ERROR_NXIO,
  65   G_IO_CHANNEL_ERROR_OVERFLOW,
  66   G_IO_CHANNEL_ERROR_PIPE,
  67   /* Other */
  68   G_IO_CHANNEL_ERROR_FAILED
  69 } GIOChannelError;
  70
  71 typedef enum
  72 {
  73   G_IO_STATUS_ERROR,
  74   G_IO_STATUS_NORMAL,
  75   G_IO_STATUS_EOF,
  76   G_IO_STATUS_AGAIN
  77 } GIOStatus;
  78
  79 typedef enum
  80 {
  81   G_SEEK_CUR,
  82   G_SEEK_SET,
  83   G_SEEK_END
  84 } GSeekType;
  85
  86 typedef enum
  87 {
  88   G_IO_FLAG_APPEND = 1 << 0,
  89   G_IO_FLAG_NONBLOCK = 1 << 1,
  90   G_IO_FLAG_IS_READABLE = 1 << 2,       /* Read only flag */
  91   G_IO_FLAG_IS_WRITABLE = 1 << 3,       /* Read only flag */
  92   G_IO_FLAG_IS_SEEKABLE = 1 << 4,       /* Read only flag */
  93   G_IO_FLAG_MASK = (1 << 5) - 1,
  94   G_IO_FLAG_GET_MASK = G_IO_FLAG_MASK,
  95   G_IO_FLAG_SET_MASK = G_IO_FLAG_APPEND | G_IO_FLAG_NONBLOCK
  96 } GIOFlags;
  97
  98 /* Misspelling in enum in 2.29.10 and earlier */
  99 #define G_IO_FLAG_IS_WRITEABLE (G_IO_FLAG_IS_WRITABLE)
 100
 101 struct _GIOChannel
 102 {
 103   /*< private >*/
 104   gint ref_count;
 105   GIOFuncs *funcs;
 106
 107   gchar *encoding;
 108   GIConv read_cd;
 109   GIConv write_cd;
 110   gchar *line_term;             /* String which indicates the end of a line of text */
 111   guint line_term_len;          /* So we can have null in the line term */
 112
 113   gsize buf_size;
 114   GString *read_buf;            /* Raw data from the channel */
 115   GString *encoded_read_buf;    /* Channel data converted to UTF-8 */
 116   GString *write_buf;           /* Data ready to be written to the file */
 117   gchar partial_write_buf[6];   /* UTF-8 partial characters, null terminated */
 118
 119   /* Group the flags together, immediately after partial_write_buf, to save memory */
 120
 121   guint use_buffer     : 1;     /* The encoding uses the buffers */
 122   guint do_encode      : 1;     /* The encoding uses the GIConv coverters */
 123   guint close_on_unref : 1;     /* Close the channel on final unref */
 124   guint is_readable    : 1;     /* Cached GIOFlag */
 125   guint is_writeable   : 1;     /* ditto */
 126   guint is_seekable    : 1;     /* ditto */
 127
 128   gpointer reserved1;
 129   gpointer reserved2;
 130 };
 131
 132 typedef gboolean (*GIOFunc) (GIOChannel   *source,
 133                              GIOCondition  condition,
 134                              gpointer      data);
 135 struct _GIOFuncs
 136 {
 137   GIOStatus (*io_read)           (GIOChannel   *channel,
 138                                   gchar        *buf,
 139                                   gsize         count,
 140                                   gsize        *bytes_read,
 141                                   GError      **err);
 142   GIOStatus (*io_write)          (GIOChannel   *channel,
 143                                   const gchar  *buf,
 144                                   gsize         count,
 145                                   gsize        *bytes_written,
 146                                   GError      **err);
 147   GIOStatus (*io_seek)           (GIOChannel   *channel,
 148                                   gint64        offset,
 149                                   GSeekType     type,
 150                                   GError      **err);
 151   GIOStatus  (*io_close)         (GIOChannel   *channel,
 152                                   GError      **err);
 153   GSource*   (*io_create_watch)  (GIOChannel   *channel,
 154                                   GIOCondition  condition);
 155   void       (*io_free)          (GIOChannel   *channel);
 156   GIOStatus  (*io_set_flags)     (GIOChannel   *channel,
 157                                   GIOFlags      flags,
 158                                   GError      **err);
 159   GIOFlags   (*io_get_flags)     (GIOChannel   *channel);
 160 };
 161
 162 GLIB_AVAILABLE_IN_ALL
 163 void        g_io_channel_init   (GIOChannel    *channel);
 164 GLIB_AVAILABLE_IN_ALL
 165 GIOChannel *g_io_channel_ref    (GIOChannel    *channel);
 166 GLIB_AVAILABLE_IN_ALL
 167 void        g_io_channel_unref  (GIOChannel    *channel);
 168
 169 GLIB_DEPRECATED_FOR(g_io_channel_read_for)
 170 GIOError    g_io_channel_read   (GIOChannel    *channel,
 171                                  gchar         *buf,
 172                                  gsize          count,
 173                                  gsize         *bytes_read);
 174
 175 GLIB_DEPRECATED_FOR(g_io_channel_write_chars)
 176 GIOError  g_io_channel_write    (GIOChannel    *channel,
 177                                  const gchar   *buf,
 178                                  gsize          count,
 179                                  gsize         *bytes_written);
 180
 181 GLIB_DEPRECATED_FOR(g_io_channel_seek_position)
 182 GIOError  g_io_channel_seek     (GIOChannel    *channel,
 183                                  gint64         offset,
 184                                  GSeekType      type);
 185
 186 GLIB_DEPRECATED_FOR(g_io_channel_shutdown)
 187 void      g_io_channel_close    (GIOChannel    *channel);
 188
 189 GLIB_AVAILABLE_IN_ALL
 190 GIOStatus g_io_channel_shutdown (GIOChannel      *channel,
 191                                  gboolean         flush,
 192                                  GError         **err);
 193 GLIB_AVAILABLE_IN_ALL
 194 guint     g_io_add_watch_full   (GIOChannel      *channel,
 195                                  gint             priority,
 196                                  GIOCondition     condition,
 197                                  GIOFunc          func,
 198                                  gpointer         user_data,
 199                                  GDestroyNotify   notify);
 200 GLIB_AVAILABLE_IN_ALL
 201 GSource * g_io_create_watch     (GIOChannel      *channel,
 202                                  GIOCondition     condition);
 203 GLIB_AVAILABLE_IN_ALL
 204 guint     g_io_add_watch        (GIOChannel      *channel,
 205                                  GIOCondition     condition,
 206                                  GIOFunc          func,
 207                                  gpointer         user_data);
 208
 209 /* character encoding conversion involved functions.
 210  */
 211
 212 GLIB_AVAILABLE_IN_ALL
 213 void                  g_io_channel_set_buffer_size      (GIOChannel   *channel,
 214                                                          gsize         size);
 215 GLIB_AVAILABLE_IN_ALL
 216 gsize                 g_io_channel_get_buffer_size      (GIOChannel   *channel);
 217 GLIB_AVAILABLE_IN_ALL
 218 GIOCondition          g_io_channel_get_buffer_condition (GIOChannel   *channel);
 219 GLIB_AVAILABLE_IN_ALL
 220 GIOStatus             g_io_channel_set_flags            (GIOChannel   *channel,
 221                                                          GIOFlags      flags,
 222                                                          GError      **error);
 223 GLIB_AVAILABLE_IN_ALL
 224 GIOFlags              g_io_channel_get_flags            (GIOChannel   *channel);
 225 GLIB_AVAILABLE_IN_ALL
 226 void                  g_io_channel_set_line_term        (GIOChannel   *channel,
 227                                                          const gchar  *line_term,
 228                                                          gint          length);
 229 GLIB_AVAILABLE_IN_ALL
 230 const gchar *         g_io_channel_get_line_term        (GIOChannel   *channel,
 231                                                          gint         *length);
 232 GLIB_AVAILABLE_IN_ALL
 233 void                  g_io_channel_set_buffered         (GIOChannel   *channel,
 234                                                          gboolean      buffered);
 235 GLIB_AVAILABLE_IN_ALL
 236 gboolean              g_io_channel_get_buffered         (GIOChannel   *channel);
 237 GLIB_AVAILABLE_IN_ALL
 238 GIOStatus             g_io_channel_set_encoding         (GIOChannel   *channel,
 239                                                          const gchar  *encoding,
 240                                                          GError      **error);
 241 GLIB_AVAILABLE_IN_ALL
 242 const gchar *         g_io_channel_get_encoding         (GIOChannel   *channel);
 243 GLIB_AVAILABLE_IN_ALL
 244 void                  g_io_channel_set_close_on_unref   (GIOChannel   *channel,
 245                                                          gboolean      do_close);
 246 GLIB_AVAILABLE_IN_ALL
 247 gboolean              g_io_channel_get_close_on_unref   (GIOChannel   *channel);
 248
 249
 250 GLIB_AVAILABLE_IN_ALL
 251 GIOStatus   g_io_channel_flush            (GIOChannel   *channel,
 252                                            GError      **error);
 253 GLIB_AVAILABLE_IN_ALL
 254 GIOStatus   g_io_channel_read_line        (GIOChannel   *channel,
 255                                            gchar       **str_return,
 256                                            gsize        *length,
 257                                            gsize        *terminator_pos,
 258                                            GError      **error);
 259 GLIB_AVAILABLE_IN_ALL
 260 GIOStatus   g_io_channel_read_line_string (GIOChannel   *channel,
 261                                            GString      *buffer,
 262                                            gsize        *terminator_pos,
 263                                            GError      **error);
 264 GLIB_AVAILABLE_IN_ALL
 265 GIOStatus   g_io_channel_read_to_end      (GIOChannel   *channel,
 266                                            gchar       **str_return,
 267                                            gsize        *length,
 268                                            GError      **error);
 269 GLIB_AVAILABLE_IN_ALL
 270 GIOStatus   g_io_channel_read_chars       (GIOChannel   *channel,
 271                                            gchar        *buf,
 272                                            gsize         count,
 273                                            gsize        *bytes_read,
 274                                            GError      **error);
 275 GLIB_AVAILABLE_IN_ALL
 276 GIOStatus   g_io_channel_read_unichar     (GIOChannel   *channel,
 277                                            gunichar     *thechar,
 278                                            GError      **error);
 279 GLIB_AVAILABLE_IN_ALL
 280 GIOStatus   g_io_channel_write_chars      (GIOChannel   *channel,
 281                                            const gchar  *buf,
 282                                            gssize        count,
 283                                            gsize        *bytes_written,
 284                                            GError      **error);
 285 GLIB_AVAILABLE_IN_ALL
 286 GIOStatus   g_io_channel_write_unichar    (GIOChannel   *channel,
 287                                            gunichar      thechar,
 288                                            GError      **error);
 289 GLIB_AVAILABLE_IN_ALL
 290 GIOStatus   g_io_channel_seek_position    (GIOChannel   *channel,
 291                                            gint64        offset,
 292                                            GSeekType     type,
 293                                            GError      **error);
 294 GLIB_AVAILABLE_IN_ALL
 295 GIOChannel* g_io_channel_new_file         (const gchar  *filename,
 296                                            const gchar  *mode,
 297                                            GError      **error);
 298
 299 /* Error handling */
 300
 301 GLIB_AVAILABLE_IN_ALL
 302 GQuark          g_io_channel_error_quark      (void);
 303 GLIB_AVAILABLE_IN_ALL
 304 GIOChannelError g_io_channel_error_from_errno (gint en);
 305
 306 /* On Unix, IO channels created with this function for any file
 307  * descriptor or socket.
 308  *
 309  * On Win32, this can be used either for files opened with the MSVCRT
 310  * (the Microsoft run-time C library) _open() or _pipe, including file
 311  * descriptors 0, 1 and 2 (corresponding to stdin, stdout and stderr),
 312  * or for Winsock SOCKETs. If the parameter is a legal file
 313  * descriptor, it is assumed to be such, otherwise it should be a
 314  * SOCKET. This relies on SOCKETs and file descriptors not
 315  * overlapping. If you want to be certain, call either
 316  * g_io_channel_win32_new_fd() or g_io_channel_win32_new_socket()
 317  * instead as appropriate.
 318  *
 319  * The term file descriptor as used in the context of Win32 refers to
 320  * the emulated Unix-like file descriptors MSVCRT provides. The native
 321  * corresponding concept is file HANDLE. There isn't as of yet a way to
 322  * get GIOChannels for Win32 file HANDLEs.
 323  */
 324 GLIB_AVAILABLE_IN_ALL
 325 GIOChannel* g_io_channel_unix_new    (int         fd);
 326 GLIB_AVAILABLE_IN_ALL
 327 gint        g_io_channel_unix_get_fd (GIOChannel *channel);
 328
 329
 330 /* Hook for GClosure / GSource integration. Don't touch */
 331 GLIB_VAR GSourceFuncs g_io_watch_funcs;
 332
 333 #ifdef G_OS_WIN32
 334
 335 /* You can use this "pseudo file descriptor" in a GPollFD to add
 336  * polling for Windows messages. GTK applications should not do that.
 337  */
 338
 339 #define G_WIN32_MSG_HANDLE 19981206
 340
 341 /* Use this to get a GPollFD from a GIOChannel, so that you can call
 342  * g_io_channel_win32_poll(). After calling this you should only use
 343  * g_io_channel_read() to read from the GIOChannel, i.e. never read()
 344  * from the underlying file descriptor. For SOCKETs, it is possible to call
 345  * recv().
 346  */
 347 GLIB_AVAILABLE_IN_ALL
 348 void        g_io_channel_win32_make_pollfd (GIOChannel   *channel,
 349                                             GIOCondition  condition,
 350                                             GPollFD      *fd);
 351
 352 /* This can be used to wait a until at least one of the channels is readable.
 353  * On Unix you would do a select() on the file descriptors of the channels.
 354  */
 355 GLIB_AVAILABLE_IN_ALL
 356 gint        g_io_channel_win32_poll   (GPollFD    *fds,
 357                                        gint        n_fds,
 358                                        gint        timeout_);
 359
 360 /* Create an IO channel for Windows messages for window handle hwnd. */
 361 #if GLIB_SIZEOF_VOID_P == 8
 362 /* We use gsize here so that it is still an integer type and not a
 363  * pointer, like the guint in the traditional prototype. We can't use
 364  * intptr_t as that is not portable enough.
 365  */
 366 GLIB_AVAILABLE_IN_ALL
 367 GIOChannel *g_io_channel_win32_new_messages (gsize hwnd);
 368 #else
 369 GLIB_AVAILABLE_IN_ALL
 370 GIOChannel *g_io_channel_win32_new_messages (guint hwnd);
 371 #endif
 372
 373 /* Create an IO channel for C runtime (emulated Unix-like) file
 374  * descriptors. After calling g_io_add_watch() on a IO channel
 375  * returned by this function, you shouldn't call read() on the file
 376  * descriptor. This is because adding polling for a file descriptor is
 377  * implemented on Win32 by starting a thread that sits blocked in a
 378  * read() from the file descriptor most of the time. All reads from
 379  * the file descriptor should be done by this internal GLib
 380  * thread. Your code should call only g_io_channel_read_chars().
 381  */
 382 GLIB_AVAILABLE_IN_ALL
 383 GIOChannel* g_io_channel_win32_new_fd (gint         fd);
 384
 385 /* Get the C runtime file descriptor of a channel. */
 386 GLIB_AVAILABLE_IN_ALL
 387 gint        g_io_channel_win32_get_fd (GIOChannel *channel);
 388
 389 /* Create an IO channel for a winsock socket. The parameter should be
 390  * a SOCKET. Contrary to IO channels for file descriptors (on *Win32),
 391  * you can use normal recv() or recvfrom() on sockets even if GLib
 392  * is polling them.
 393  */
 394 GLIB_AVAILABLE_IN_ALL
 395 GIOChannel *g_io_channel_win32_new_socket (gint socket);
 396
 397 GLIB_DEPRECATED_FOR(g_io_channel_win32_new_socket)
 398 GIOChannel *g_io_channel_win32_new_stream_socket (gint socket);
 399
 400 GLIB_AVAILABLE_IN_ALL
 401 void        g_io_channel_win32_set_debug (GIOChannel *channel,
 402                                           gboolean    flag);
 403
 404 #endif
 405
 406 #ifdef G_OS_WIN32
 407 #define g_io_channel_new_file g_io_channel_new_file_utf8
 408
 409 GLIB_AVAILABLE_IN_ALL
 410 GIOChannel *g_io_channel_new_file_utf8 (const gchar  *filename,
 411                                         const gchar  *mode,
 412                                         GError      **error);
 413 #endif
 414
 415 G_END_DECLS
 416
 417 #endif /* __G_IOCHANNEL_H__ */