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