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 #if !defined (__GLIB_H_INSIDE__) && !defined (GLIB_COMPILATION)
  28 #error "Only <glib.h> can be included directly."
  29 #endif
  30
  31 #ifndef __G_IOCHANNEL_H__
  32 #define __G_IOCHANNEL_H__
  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 /*< flags >*/
  87 {
  88   G_IO_IN       GLIB_SYSDEF_POLLIN,
  89   G_IO_OUT      GLIB_SYSDEF_POLLOUT,
  90   G_IO_PRI      GLIB_SYSDEF_POLLPRI,
  91   G_IO_ERR      GLIB_SYSDEF_POLLERR,
  92   G_IO_HUP      GLIB_SYSDEF_POLLHUP,
  93   G_IO_NVAL     GLIB_SYSDEF_POLLNVAL
  94 } GIOCondition;
  95
  96 typedef enum
  97 {
  98   G_IO_FLAG_APPEND = 1 << 0,
  99   G_IO_FLAG_NONBLOCK = 1 << 1,
 100   G_IO_FLAG_IS_READABLE = 1 << 2,       /* Read only flag */
 101   G_IO_FLAG_IS_WRITABLE = 1 << 3,       /* Read only flag */
 102   G_IO_FLAG_IS_SEEKABLE = 1 << 4,       /* Read only flag */
 103   G_IO_FLAG_MASK = (1 << 5) - 1,
 104   G_IO_FLAG_GET_MASK = G_IO_FLAG_MASK,
 105   G_IO_FLAG_SET_MASK = G_IO_FLAG_APPEND | G_IO_FLAG_NONBLOCK
 106 } GIOFlags;
 107
 108 /* Misspelling in enum in 2.29.10 and earlier */
 109 #define G_IO_FLAG_IS_WRITEABLE (G_IO_FLAG_IS_WRITABLE)
 110
 111 struct _GIOChannel
 112 {
 113   /*< private >*/
 114   gint ref_count;
 115   GIOFuncs *funcs;
 116
 117   gchar *encoding;
 118   GIConv read_cd;
 119   GIConv write_cd;
 120   gchar *line_term;             /* String which indicates the end of a line of text */
 121   guint line_term_len;          /* So we can have null in the line term */
 122
 123   gsize buf_size;
 124   GString *read_buf;            /* Raw data from the channel */
 125   GString *encoded_read_buf;    /* Channel data converted to UTF-8 */
 126   GString *write_buf;           /* Data ready to be written to the file */
 127   gchar partial_write_buf[6];   /* UTF-8 partial characters, null terminated */
 128
 129   /* Group the flags together, immediately after partial_write_buf, to save memory */
 130
 131   guint use_buffer     : 1;     /* The encoding uses the buffers */
 132   guint do_encode      : 1;     /* The encoding uses the GIConv coverters */
 133   guint close_on_unref : 1;     /* Close the channel on final unref */
 134   guint is_readable    : 1;     /* Cached GIOFlag */
 135   guint is_writeable   : 1;     /* ditto */
 136   guint is_seekable    : 1;     /* ditto */
 137
 138   gpointer reserved1;
 139   gpointer reserved2;
 140 };
 141
 142 typedef gboolean (*GIOFunc) (GIOChannel   *source,
 143                              GIOCondition  condition,
 144                              gpointer      data);
 145 struct _GIOFuncs
 146 {
 147   GIOStatus (*io_read)           (GIOChannel   *channel,
 148                                   gchar        *buf,
 149                                   gsize         count,
 150                                   gsize        *bytes_read,
 151                                   GError      **err);
 152   GIOStatus (*io_write)          (GIOChannel   *channel,
 153                                   const gchar  *buf,
 154                                   gsize         count,
 155                                   gsize        *bytes_written,
 156                                   GError      **err);
 157   GIOStatus (*io_seek)           (GIOChannel   *channel,
 158                                   gint64        offset,
 159                                   GSeekType     type,
 160                                   GError      **err);
 161   GIOStatus  (*io_close)         (GIOChannel   *channel,
 162                                   GError      **err);
 163   GSource*   (*io_create_watch)  (GIOChannel   *channel,
 164                                   GIOCondition  condition);
 165   void       (*io_free)          (GIOChannel   *channel);
 166   GIOStatus  (*io_set_flags)     (GIOChannel   *channel,
 167                                   GIOFlags      flags,
 168                                   GError      **err);
 169   GIOFlags   (*io_get_flags)     (GIOChannel   *channel);
 170 };
 171
 172 void        g_io_channel_init   (GIOChannel    *channel);
 173 GIOChannel *g_io_channel_ref    (GIOChannel    *channel);
 174 void        g_io_channel_unref  (GIOChannel    *channel);
 175
 176 GLIB_DEPRECATED_FOR(g_io_channel_read_for)
 177 GIOError    g_io_channel_read   (GIOChannel    *channel,
 178                                  gchar         *buf,
 179                                  gsize          count,
 180                                  gsize         *bytes_read);
 181
 182 GLIB_DEPRECATED_FOR(g_io_channel_write_chars)
 183 GIOError  g_io_channel_write    (GIOChannel    *channel,
 184                                  const gchar   *buf,
 185                                  gsize          count,
 186                                  gsize         *bytes_written);
 187
 188 GLIB_DEPRECATED_FOR(g_io_channel_seek_position)
 189 GIOError  g_io_channel_seek     (GIOChannel    *channel,
 190                                  gint64         offset,
 191                                  GSeekType      type);
 192
 193 GLIB_DEPRECATED_FOR(g_io_channel_shutdown)
 194 void      g_io_channel_close    (GIOChannel    *channel);
 195
 196 GIOStatus g_io_channel_shutdown (GIOChannel      *channel,
 197                                  gboolean         flush,
 198                                  GError         **err);
 199 guint     g_io_add_watch_full   (GIOChannel      *channel,
 200                                  gint             priority,
 201                                  GIOCondition     condition,
 202                                  GIOFunc          func,
 203                                  gpointer         user_data,
 204                                  GDestroyNotify   notify);
 205 GSource * g_io_create_watch     (GIOChannel      *channel,
 206                                  GIOCondition     condition);
 207 guint     g_io_add_watch        (GIOChannel      *channel,
 208                                  GIOCondition     condition,
 209                                  GIOFunc          func,
 210                                  gpointer         user_data);
 211
 212 /* character encoding conversion involved functions.
 213  */
 214
 215 void                  g_io_channel_set_buffer_size      (GIOChannel   *channel,
 216                                                          gsize         size);
 217 gsize                 g_io_channel_get_buffer_size      (GIOChannel   *channel);
 218 GIOCondition          g_io_channel_get_buffer_condition (GIOChannel   *channel);
 219 GIOStatus             g_io_channel_set_flags            (GIOChannel   *channel,
 220                                                          GIOFlags      flags,
 221                                                          GError      **error);
 222 GIOFlags              g_io_channel_get_flags            (GIOChannel   *channel);
 223 void                  g_io_channel_set_line_term        (GIOChannel   *channel,
 224                                                          const gchar  *line_term,
 225                                                          gint          length);
 226 const gchar *         g_io_channel_get_line_term        (GIOChannel   *channel,
 227                                                          gint         *length);
 228 void                  g_io_channel_set_buffered         (GIOChannel   *channel,
 229                                                          gboolean      buffered);
 230 gboolean              g_io_channel_get_buffered         (GIOChannel   *channel);
 231 GIOStatus             g_io_channel_set_encoding         (GIOChannel   *channel,
 232                                                          const gchar  *encoding,
 233                                                          GError      **error);
 234 const gchar *         g_io_channel_get_encoding         (GIOChannel   *channel);
 235 void                  g_io_channel_set_close_on_unref   (GIOChannel   *channel,
 236                                                          gboolean      do_close);
 237 gboolean              g_io_channel_get_close_on_unref   (GIOChannel   *channel);
 238
 239
 240 GIOStatus   g_io_channel_flush            (GIOChannel   *channel,
 241                                            GError      **error);
 242 GIOStatus   g_io_channel_read_line        (GIOChannel   *channel,
 243                                            gchar       **str_return,
 244                                            gsize        *length,
 245                                            gsize        *terminator_pos,
 246                                            GError      **error);
 247 GIOStatus   g_io_channel_read_line_string (GIOChannel   *channel,
 248                                            GString      *buffer,
 249                                            gsize        *terminator_pos,
 250                                            GError      **error);
 251 GIOStatus   g_io_channel_read_to_end      (GIOChannel   *channel,
 252                                            gchar       **str_return,
 253                                            gsize        *length,
 254                                            GError      **error);
 255 GIOStatus   g_io_channel_read_chars       (GIOChannel   *channel,
 256                                            gchar        *buf,
 257                                            gsize         count,
 258                                            gsize        *bytes_read,
 259                                            GError      **error);
 260 GIOStatus   g_io_channel_read_unichar     (GIOChannel   *channel,
 261                                            gunichar     *thechar,
 262                                            GError      **error);
 263 GIOStatus   g_io_channel_write_chars      (GIOChannel   *channel,
 264                                            const gchar  *buf,
 265                                            gssize        count,
 266                                            gsize        *bytes_written,
 267                                            GError      **error);
 268 GIOStatus   g_io_channel_write_unichar    (GIOChannel   *channel,
 269                                            gunichar      thechar,
 270                                            GError      **error);
 271 GIOStatus   g_io_channel_seek_position    (GIOChannel   *channel,
 272                                            gint64        offset,
 273                                            GSeekType     type,
 274                                            GError      **error);
 275 #ifdef G_OS_WIN32
 276 #define g_io_channel_new_file g_io_channel_new_file_utf8
 277 #endif
 278
 279 GIOChannel* g_io_channel_new_file         (const gchar  *filename,
 280                                            const gchar  *mode,
 281                                            GError      **error);
 282
 283 /* Error handling */
 284
 285 GQuark          g_io_channel_error_quark      (void);
 286 GIOChannelError g_io_channel_error_from_errno (gint en);
 287
 288 /* On Unix, IO channels created with this function for any file
 289  * descriptor or socket.
 290  *
 291  * On Win32, this can be used either for files opened with the MSVCRT
 292  * (the Microsoft run-time C library) _open() or _pipe, including file
 293  * descriptors 0, 1 and 2 (corresponding to stdin, stdout and stderr),
 294  * or for Winsock SOCKETs. If the parameter is a legal file
 295  * descriptor, it is assumed to be such, otherwise it should be a
 296  * SOCKET. This relies on SOCKETs and file descriptors not
 297  * overlapping. If you want to be certain, call either
 298  * g_io_channel_win32_new_fd() or g_io_channel_win32_new_socket()
 299  * instead as appropriate.
 300  *
 301  * The term file descriptor as used in the context of Win32 refers to
 302  * the emulated Unix-like file descriptors MSVCRT provides. The native
 303  * corresponding concept is file HANDLE. There isn't as of yet a way to
 304  * get GIOChannels for Win32 file HANDLEs.
 305  */
 306 GIOChannel* g_io_channel_unix_new    (int         fd);
 307 gint        g_io_channel_unix_get_fd (GIOChannel *channel);
 308
 309
 310 /* Hook for GClosure / GSource integration. Don't touch */
 311 GLIB_VAR GSourceFuncs g_io_watch_funcs;
 312
 313 #ifdef G_OS_WIN32
 314
 315 /* You can use this "pseudo file descriptor" in a GPollFD to add
 316  * polling for Windows messages. GTK applications should not do that.
 317  */
 318
 319 #define G_WIN32_MSG_HANDLE 19981206
 320
 321 /* Use this to get a GPollFD from a GIOChannel, so that you can call
 322  * g_io_channel_win32_poll(). After calling this you should only use
 323  * g_io_channel_read() to read from the GIOChannel, i.e. never read()
 324  * from the underlying file descriptor. For SOCKETs, it is possible to call
 325  * recv().
 326  */
 327 void        g_io_channel_win32_make_pollfd (GIOChannel   *channel,
 328                                             GIOCondition  condition,
 329                                             GPollFD      *fd);
 330
 331 /* This can be used to wait a until at least one of the channels is readable.
 332  * On Unix you would do a select() on the file descriptors of the channels.
 333  */
 334 gint        g_io_channel_win32_poll   (GPollFD    *fds,
 335                                        gint        n_fds,
 336                                        gint        timeout_);
 337
 338 /* Create an IO channel for Windows messages for window handle hwnd. */
 339 #if GLIB_SIZEOF_VOID_P == 8
 340 /* We use gsize here so that it is still an integer type and not a
 341  * pointer, like the guint in the traditional prototype. We can't use
 342  * intptr_t as that is not portable enough.
 343  */
 344 GIOChannel *g_io_channel_win32_new_messages (gsize hwnd);
 345 #else
 346 GIOChannel *g_io_channel_win32_new_messages (guint hwnd);
 347 #endif
 348
 349 /* Create an IO channel for C runtime (emulated Unix-like) file
 350  * descriptors. After calling g_io_add_watch() on a IO channel
 351  * returned by this function, you shouldn't call read() on the file
 352  * descriptor. This is because adding polling for a file descriptor is
 353  * implemented on Win32 by starting a thread that sits blocked in a
 354  * read() from the file descriptor most of the time. All reads from
 355  * the file descriptor should be done by this internal GLib
 356  * thread. Your code should call only g_io_channel_read_chars().
 357  */
 358 GIOChannel* g_io_channel_win32_new_fd (gint         fd);
 359
 360 /* Get the C runtime file descriptor of a channel. */
 361 gint        g_io_channel_win32_get_fd (GIOChannel *channel);
 362
 363 /* Create an IO channel for a winsock socket. The parameter should be
 364  * a SOCKET. Contrary to IO channels for file descriptors (on *Win32),
 365  * you can use normal recv() or recvfrom() on sockets even if GLib
 366  * is polling them.
 367  */
 368 GIOChannel *g_io_channel_win32_new_socket (gint socket);
 369
 370 #endif
 371
 372 G_END_DECLS
 373
 374 #endif /* __G_IOCHANNEL_H__ */