aboutsummaryrefslogtreecommitdiffstats
path: root/camel/camel-stream-buffered-fs.c
blob: 1156a726d9a157caf383cad901f804e3d8ff2ff1 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/* camel-stream-buffered-fs.c : file system based stream with buffer*/

/* 
 *
 * Copyright (C) 1999 Bertrand Guiheneuf <Bertrand.Guiheneuf@inria.fr> .
 *
 * This program is free software; you can redistribute it and/or 
 * modify it under the terms of the GNU General Public License as 
 * published by the Free Software Foundation; either version 2 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 * USA
 */


#include <config.h>
#include "camel-stream-buffered-fs.h"
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <errno.h>
#include "camel-log.h"

static CamelStreamFsClass *parent_class=NULL;


/* Returns the class for a CamelStreamBufferedFs */
#define CSBFS_CLASS(so) CAMEL_STREAM_BUFFERED_FS_CLASS (GTK_OBJECT(so)->klass)
#define CSFS_CLASS(so) CAMEL_STREAM_FS_CLASS (GTK_OBJECT(so)->klass)
#define CS_CLASS(so) CAMEL_STREAM_CLASS (GTK_OBJECT(so)->klass)

static gint _read (CamelStream *stream, gchar *buffer, gint n);
static gint _write (CamelStream *stream, const gchar *buffer, gint n);
static void _flush (CamelStream *stream);
static gint _available (CamelStream *stream);
static gboolean _eos (CamelStream *stream);
static void _close (CamelStream *stream);
static gint _seek (CamelStream *stream, gint offset, CamelStreamSeekPolicy policy);

static void _finalize (GtkObject *object);
static void _destroy (GtkObject *object);

static void
camel_stream_buffered_fs_class_init (CamelStreamBufferedFsClass *camel_stream_buffered_fs_class)
{
    CamelStreamClass *camel_stream_class = CAMEL_STREAM_CLASS (camel_stream_buffered_fs_class);
    GtkObjectClass *gtk_object_class = GTK_OBJECT_CLASS (camel_stream_buffered_fs_class);

    parent_class = gtk_type_class (camel_stream_fs_get_type ());
    
    /* virtual method definition */

    /* virtual method overload */
    camel_stream_class->read = _read;

    gtk_object_class->finalize = _finalize;
    gtk_object_class->destroy = _destroy;

}

static void
camel_stream_buffered_fs_init (gpointer   object,  gpointer   klass)
{
    CamelStreamBufferedFs *stream = CAMEL_STREAM_BUFFERED_FS (object);

    stream->buffer_size = 200;
    stream->read_buffer = g_new (gchar, stream->buffer_size);
    stream->write_buffer = g_new (gchar, stream->buffer_size);
    stream->read_pos = 0;
    stream->read_pos_max = 0;
    stream->write_pos = 0;
    stream->write_pos_max = stream->buffer_size;
}

GtkType
camel_stream_buffered_fs_get_type (void)
{
    static GtkType camel_stream_buffered_fs_type = 0;
    
    gdk_threads_enter ();
    if (!camel_stream_buffered_fs_type) {
        GtkTypeInfo camel_stream_buffered_fs_info = 
        {
            "CamelStreamBufferedFs",
            sizeof (CamelStreamBufferedFs),
            sizeof (CamelStreamBufferedFsClass),
            (GtkClassInitFunc) camel_stream_buffered_fs_class_init,
            (GtkObjectInitFunc) camel_stream_buffered_fs_init,
                /* reserved_1 */ NULL,
                /* reserved_2 */ NULL,
            (GtkClassInitFunc) NULL,
        };
        
        camel_stream_buffered_fs_type = gtk_type_unique (camel_stream_fs_get_type (), &camel_stream_buffered_fs_info);
    }
    gdk_threads_leave ();
    return camel_stream_buffered_fs_type;
}


static void           
_destroy (GtkObject *object)
{
    CamelStreamBufferedFs *stream_buffered_fs = CAMEL_STREAM_BUFFERED_FS (object);
    
    CAMEL_LOG_FULL_DEBUG ("Entering CamelStreamBufferedFs::destroy\n");
    

    GTK_OBJECT_CLASS (parent_class)->destroy (object);
    
    CAMEL_LOG_FULL_DEBUG ("Leaving CamelStreamBufferedFs::destroy\n");
}


static void           
_finalize (GtkObject *object)
{
    CamelStreamBufferedFs *stream_buffered_fs = CAMEL_STREAM_BUFFERED_FS (object);


    CAMEL_LOG_FULL_DEBUG ("Entering CamelStreamBufferedFs::finalize\n");
    
    g_free (stream_buffered_fs->read_buffer);
    g_free (stream_buffered_fs->write_buffer);
    
    GTK_OBJECT_CLASS (parent_class)->finalize (object);
    CAMEL_LOG_FULL_DEBUG ("Leaving CamelStreamBufferedFs::finalize\n");
}



CamelStream *
camel_stream_buffered_fs_new_with_name (const gchar *name, CamelStreamFsMode mode)
{
    CamelStreamFs *stream_buffered_fs;
    stream_buffered_fs = gtk_type_new (camel_stream_buffered_fs_get_type ());
    CSFS_CLASS (stream_buffered_fs)->init_with_name (stream_buffered_fs, name, mode);
    
    return CAMEL_STREAM (stream_buffered_fs);
    
}

CamelStream *
camel_stream_buffered_fs_new_with_fd (int fd)
{
    CamelStreamFs *stream_buffered_fs;
    
    CAMEL_LOG_FULL_DEBUG ( "Entering CamelStream::new_with_fd  fd=%d\n",fd);
    stream_buffered_fs = gtk_type_new (camel_stream_buffered_fs_get_type ());
    CSFS_CLASS (stream_buffered_fs)->init_with_fd (stream_buffered_fs, fd);

    
    return CAMEL_STREAM (stream_buffered_fs);
}

/**
 * _read: read bytes from a stream
 * @stream: stream
 * @buffer: buffer where bytes are stored
 * @n: max number of bytes to read
 * 
 * 
 * 
 * Return value: number of bytes actually read.
 **/
static gint
_read (CamelStream *stream, gchar *buffer, gint n)
{
    CamelStreamBufferedFs *sbf = CAMEL_STREAM_BUFFERED_FS (stream);
    gint v;
    gint nb_bytes_buffered;
    gint nb_bytes_to_read = n;
    gint nb_bytes_read = 0;
    gint bytes_chunk;
    gboolean eof = FALSE;

    g_return_val_if_fail (n>0, n);

    nb_bytes_buffered = sbf->read_pos_max - sbf->read_pos;
    while ( (!eof) && (nb_bytes_to_read>0)) { 
        if (nb_bytes_buffered <= 0) {
            /* have to read some data on disk */
            v = CAMEL_STREAM_CLASS (parent_class)->read (stream, sbf->read_buffer, sbf->buffer_size);
            nb_bytes_buffered = v;
            sbf->read_pos_max = v;
            sbf->read_pos = 0;
        }
        
        /* nb of bytes to put inside buffer */
        bytes_chunk = MIN (nb_bytes_buffered, nb_bytes_to_read);

        if (bytes_chunk > 0) {
            /* copy some bytes from the cache */
            memcpy (buffer, sbf->read_buffer + sbf->read_pos, bytes_chunk);
            nb_bytes_buffered -= bytes_chunk;
            nb_bytes_to_read -= bytes_chunk;
            nb_bytes_read += bytes_chunk;
            sbf->read_pos += bytes_chunk;
             
        } else /* nb_bytes_to_read is >0 so if bytes_chunk is <0 
            * there was no data available */
            eof = TRUE;
    }
            
    
    
    return nb_bytes_read;
}


static gint
_write (CamelStream *stream, const gchar *buffer, gint n)
{
    return 0;
}



static void
_flush (CamelStream *stream)
{
    
}



static gint 
_available (CamelStream *stream)
{
    return 0;
}


static gboolean
_eos (CamelStream *stream)
{
    return FALSE;
}



static void
_close (CamelStream *stream)
{
    
}


static gint
_seek (CamelStream *stream, gint offset, CamelStreamSeekPolicy policy)
{
    return 0;
}