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