libpurple/circularbuffer.h

   1 /* Purple is the legal property of its developers, whose names are too numerous
   2  * to list here.  Please refer to the COPYRIGHT file distributed with this
   3  * source distribution.
   4  *
   5  * This program is free software; you can redistribute it and/or modify
   6  * it under the terms of the GNU General Public License as published by
   7  * the Free Software Foundation; either version 2 of the License, or
   8  * (at your option) any later version.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License
  16  * along with this program; if not, write to the Free Software
  17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02111-1301  USA
  18  */
  19
  20 #ifndef PURPLE_CIRCULAR_BUFFER_H
  21 #define PURPLE_CIRCULAR_BUFFER_H
  22 /**
  23  * SECTION:circularbuffer
  24  * @section_id: libpurple-circularbuffer
  25  * @short_description: <filename>circularbuffer.h</filename>
  26  * @title: Buffer Utility Functions
  27  */
  28
  29 #include <glib.h>
  30 #include <glib-object.h>
  31
  32 G_BEGIN_DECLS
  33
  34 #define PURPLE_TYPE_CIRCULAR_BUFFER (purple_circular_buffer_get_type())
  35
  36 G_DECLARE_DERIVABLE_TYPE(PurpleCircularBuffer, purple_circular_buffer, PURPLE,
  37                          CIRCULAR_BUFFER, GObject)
  38
  39 struct _PurpleCircularBufferClass {
  40         /*< private >*/
  41         GObjectClass parent;
  42
  43         void (*grow)(PurpleCircularBuffer *buffer, gsize len);
  44         void (*append)(PurpleCircularBuffer *buffer, gconstpointer src, gsize len);
  45         gsize (*max_read_size)(PurpleCircularBuffer *buffer);
  46         gboolean (*mark_read)(PurpleCircularBuffer *buffer, gsize len);
  47
  48         void (*purple_reserved1)(void);
  49         void (*purple_reserved2)(void);
  50         void (*purple_reserved3)(void);
  51         void (*purple_reserved4)(void);
  52 };
  53
  54 /**
  55  * purple_circular_buffer_new:
  56  * @growsize: The amount that the buffer should grow the first time data
  57  *                 is appended and every time more space is needed.  Pass in
  58  *                 "0" to use the default of 256 bytes.
  59  *
  60  * Creates a new circular buffer.  This will not allocate any memory for the
  61  * actual buffer until data is appended to it.
  62  *
  63  * Returns: The new PurpleCircularBuffer.
  64  */
  65 PurpleCircularBuffer *purple_circular_buffer_new(gsize growsize);
  66
  67 /**
  68  * purple_circular_buffer_append:
  69  * @buffer: The PurpleCircularBuffer to which to append the data
  70  * @src: pointer to the data to copy into the buffer
  71  * @len: number of bytes to copy into the buffer
  72  *
  73  * Append data to the PurpleCircularBuffer.  This will grow the internal
  74  * buffer to fit the added data, if needed.
  75  */
  76 void purple_circular_buffer_append(PurpleCircularBuffer *buffer, gconstpointer src, gsize len);
  77
  78 /**
  79  * purple_circular_buffer_get_max_read:
  80  * @buffer: the PurpleCircularBuffer for which to determine the maximum
  81  *            contiguous bytes that can be read.
  82  *
  83  * Determine the maximum number of contiguous bytes that can be read from the
  84  * PurpleCircularBuffer.
  85  * Note: This may not be the total number of bytes that are buffered - a
  86  * subsequent call after calling purple_circular_buffer_mark_read() may indicate
  87  * more data is available to read.
  88  *
  89  * Returns: the number of bytes that can be read from the PurpleCircularBuffer
  90  */
  91 gsize purple_circular_buffer_get_max_read(PurpleCircularBuffer *buffer);
  92
  93 /**
  94  * purple_circular_buffer_mark_read:
  95  * @buffer: The PurpleCircularBuffer to mark bytes read from
  96  * @len: The number of bytes to mark as read
  97  *
  98  * Mark the number of bytes that have been read from the buffer.
  99  *
 100  * Returns: TRUE if we successfully marked the bytes as having been read, FALSE
 101  *         otherwise.
 102  */
 103 gboolean purple_circular_buffer_mark_read(PurpleCircularBuffer *buffer, gsize len);
 104
 105 /**
 106  * purple_circular_buffer_grow:
 107  * @buffer: The PurpleCircularBuffer to grow.
 108  * @len:    The number of bytes the buffer should be able to hold.
 109  *
 110  * Increases the buffer size by a multiple of grow size, so that it can hold at
 111  * least 'len' bytes.
 112  */
 113 void purple_circular_buffer_grow(PurpleCircularBuffer *buffer, gsize len);
 114
 115 /**
 116  * purple_circular_buffer_get_grow_size:
 117  * @buffer: The PurpleCircularBuffer from which to get grow size.
 118  *
 119  * Returns the number of bytes by which the buffer grows when more space is
 120  * needed.
 121  *
 122  * Returns: The grow size of the buffer.
 123  */
 124 gsize purple_circular_buffer_get_grow_size(PurpleCircularBuffer *buffer);
 125
 126 /**
 127  * purple_circular_buffer_get_used:
 128  * @buffer: The PurpleCircularBuffer from which to get used count.
 129  *
 130  * Returns the number of bytes of this buffer that contain unread data.
 131  *
 132  * Returns: The number of bytes that contain unread data.
 133  */
 134 gsize purple_circular_buffer_get_used(PurpleCircularBuffer *buffer);
 135
 136 /**
 137  * purple_circular_buffer_get_output:
 138  * @buffer: The PurpleCircularBuffer from which to get the output pointer.
 139  *
 140  * Returns the output pointer of the buffer, where unread data is available.
 141  * Use purple_circular_buffer_get_max_read() to determine the number of
 142  * contiguous bytes that can be read from this output. After reading the data,
 143  * call purple_circular_buffer_mark_read() to mark the retrieved data as read.
 144  *
 145  * Returns: The output pointer for the buffer.
 146  */
 147 const gchar *purple_circular_buffer_get_output(PurpleCircularBuffer *buffer);
 148
 149 /**
 150  * purple_circular_buffer_reset:
 151  * @buffer: The PurpleCircularBuffer to reset.
 152  *
 153  * Resets the buffer contents.
 154  */
 155 void purple_circular_buffer_reset(PurpleCircularBuffer *buffer);
 156
 157 G_END_DECLS
 158
 159 #endif /* PURPLE_CIRCULAR_BUFFER_H */
 160