diff options
Diffstat (limited to 'src/transport/tcp_server_mst_legacy.c')
-rw-r--r-- | src/transport/tcp_server_mst_legacy.c | 311 |
1 files changed, 311 insertions, 0 deletions
diff --git a/src/transport/tcp_server_mst_legacy.c b/src/transport/tcp_server_mst_legacy.c new file mode 100644 index 000000000..ba42b1837 --- /dev/null +++ b/src/transport/tcp_server_mst_legacy.c | |||
@@ -0,0 +1,311 @@ | |||
1 | /* | ||
2 | This file is part of GNUnet. | ||
3 | Copyright (C) 2010 GNUnet e.V. | ||
4 | |||
5 | GNUnet is free software; you can redistribute it and/or modify | ||
6 | it under the terms of the GNU General Public License as published | ||
7 | by the Free Software Foundation; either version 3, or (at your | ||
8 | option) any later version. | ||
9 | |||
10 | GNUnet is distributed in the hope that it will be useful, but | ||
11 | WITHOUT ANY WARRANTY; without even the implied warranty of | ||
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | ||
13 | General Public License for more details. | ||
14 | |||
15 | You should have received a copy of the GNU General Public License | ||
16 | along with GNUnet; see the file COPYING. If not, write to the | ||
17 | Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, | ||
18 | Boston, MA 02110-1301, USA. | ||
19 | */ | ||
20 | |||
21 | /** | ||
22 | * @file util/server_mst.c | ||
23 | * @brief convenience functions for handling inbound message buffers | ||
24 | * @author Christian Grothoff | ||
25 | */ | ||
26 | |||
27 | #include "platform.h" | ||
28 | #include "gnunet_util_lib.h" | ||
29 | |||
30 | |||
31 | #if HAVE_UNALIGNED_64_ACCESS | ||
32 | #define ALIGN_FACTOR 4 | ||
33 | #else | ||
34 | #define ALIGN_FACTOR 8 | ||
35 | #endif | ||
36 | |||
37 | |||
38 | /** | ||
39 | * Handle to a message stream tokenizer. | ||
40 | */ | ||
41 | struct GNUNET_SERVER_MessageStreamTokenizer | ||
42 | { | ||
43 | |||
44 | /** | ||
45 | * Function to call on completed messages. | ||
46 | */ | ||
47 | GNUNET_SERVER_MessageTokenizerCallback cb; | ||
48 | |||
49 | /** | ||
50 | * Closure for @e cb. | ||
51 | */ | ||
52 | void *cb_cls; | ||
53 | |||
54 | /** | ||
55 | * Size of the buffer (starting at @e hdr). | ||
56 | */ | ||
57 | size_t curr_buf; | ||
58 | |||
59 | /** | ||
60 | * How many bytes in buffer have we already processed? | ||
61 | */ | ||
62 | size_t off; | ||
63 | |||
64 | /** | ||
65 | * How many bytes in buffer are valid right now? | ||
66 | */ | ||
67 | size_t pos; | ||
68 | |||
69 | /** | ||
70 | * Beginning of the buffer. Typed like this to force alignment. | ||
71 | */ | ||
72 | struct GNUNET_MessageHeader *hdr; | ||
73 | |||
74 | }; | ||
75 | |||
76 | |||
77 | |||
78 | /** | ||
79 | * Create a message stream tokenizer. | ||
80 | * | ||
81 | * @param cb function to call on completed messages | ||
82 | * @param cb_cls closure for @a cb | ||
83 | * @return handle to tokenizer | ||
84 | */ | ||
85 | struct GNUNET_SERVER_MessageStreamTokenizer * | ||
86 | GNUNET_SERVER_mst_create (GNUNET_SERVER_MessageTokenizerCallback cb, | ||
87 | void *cb_cls) | ||
88 | { | ||
89 | struct GNUNET_SERVER_MessageStreamTokenizer *ret; | ||
90 | |||
91 | ret = GNUNET_new (struct GNUNET_SERVER_MessageStreamTokenizer); | ||
92 | ret->hdr = GNUNET_malloc (GNUNET_SERVER_MIN_BUFFER_SIZE); | ||
93 | ret->curr_buf = GNUNET_SERVER_MIN_BUFFER_SIZE; | ||
94 | ret->cb = cb; | ||
95 | ret->cb_cls = cb_cls; | ||
96 | return ret; | ||
97 | } | ||
98 | |||
99 | |||
100 | /** | ||
101 | * Add incoming data to the receive buffer and call the | ||
102 | * callback for all complete messages. | ||
103 | * | ||
104 | * @param mst tokenizer to use | ||
105 | * @param client_identity ID of client for which this is a buffer | ||
106 | * @param buf input data to add | ||
107 | * @param size number of bytes in @a buf | ||
108 | * @param purge should any excess bytes in the buffer be discarded | ||
109 | * (i.e. for packet-based services like UDP) | ||
110 | * @param one_shot only call callback once, keep rest of message in buffer | ||
111 | * @return #GNUNET_OK if we are done processing (need more data) | ||
112 | * #GNUNET_NO if @a one_shot was set and we have another message ready | ||
113 | * #GNUNET_SYSERR if the data stream is corrupt | ||
114 | */ | ||
115 | int | ||
116 | GNUNET_SERVER_mst_receive (struct GNUNET_SERVER_MessageStreamTokenizer *mst, | ||
117 | void *client_identity, | ||
118 | const char *buf, size_t size, | ||
119 | int purge, int one_shot) | ||
120 | { | ||
121 | const struct GNUNET_MessageHeader *hdr; | ||
122 | size_t delta; | ||
123 | uint16_t want; | ||
124 | char *ibuf; | ||
125 | int need_align; | ||
126 | unsigned long offset; | ||
127 | int ret; | ||
128 | |||
129 | GNUNET_assert (mst->off <= mst->pos); | ||
130 | GNUNET_assert (mst->pos <= mst->curr_buf); | ||
131 | LOG (GNUNET_ERROR_TYPE_DEBUG, | ||
132 | "Server-mst receives %u bytes with %u bytes already in private buffer\n", | ||
133 | (unsigned int) size, (unsigned int) (mst->pos - mst->off)); | ||
134 | ret = GNUNET_OK; | ||
135 | ibuf = (char *) mst->hdr; | ||
136 | while (mst->pos > 0) | ||
137 | { | ||
138 | do_align: | ||
139 | GNUNET_assert (mst->pos >= mst->off); | ||
140 | if ((mst->curr_buf - mst->off < sizeof (struct GNUNET_MessageHeader)) || | ||
141 | (0 != (mst->off % ALIGN_FACTOR))) | ||
142 | { | ||
143 | /* need to align or need more space */ | ||
144 | mst->pos -= mst->off; | ||
145 | memmove (ibuf, &ibuf[mst->off], mst->pos); | ||
146 | mst->off = 0; | ||
147 | } | ||
148 | if (mst->pos - mst->off < sizeof (struct GNUNET_MessageHeader)) | ||
149 | { | ||
150 | delta = | ||
151 | GNUNET_MIN (sizeof (struct GNUNET_MessageHeader) - | ||
152 | (mst->pos - mst->off), size); | ||
153 | GNUNET_memcpy (&ibuf[mst->pos], buf, delta); | ||
154 | mst->pos += delta; | ||
155 | buf += delta; | ||
156 | size -= delta; | ||
157 | } | ||
158 | if (mst->pos - mst->off < sizeof (struct GNUNET_MessageHeader)) | ||
159 | { | ||
160 | if (purge) | ||
161 | { | ||
162 | mst->off = 0; | ||
163 | mst->pos = 0; | ||
164 | } | ||
165 | return GNUNET_OK; | ||
166 | } | ||
167 | hdr = (const struct GNUNET_MessageHeader *) &ibuf[mst->off]; | ||
168 | want = ntohs (hdr->size); | ||
169 | if (want < sizeof (struct GNUNET_MessageHeader)) | ||
170 | { | ||
171 | GNUNET_break_op (0); | ||
172 | return GNUNET_SYSERR; | ||
173 | } | ||
174 | if ( (mst->curr_buf - mst->off < want) && | ||
175 | (mst->off > 0) ) | ||
176 | { | ||
177 | /* can get more space by moving */ | ||
178 | mst->pos -= mst->off; | ||
179 | memmove (ibuf, &ibuf[mst->off], mst->pos); | ||
180 | mst->off = 0; | ||
181 | } | ||
182 | if (mst->curr_buf < want) | ||
183 | { | ||
184 | /* need to get more space by growing buffer */ | ||
185 | GNUNET_assert (0 == mst->off); | ||
186 | mst->hdr = GNUNET_realloc (mst->hdr, want); | ||
187 | ibuf = (char *) mst->hdr; | ||
188 | mst->curr_buf = want; | ||
189 | } | ||
190 | hdr = (const struct GNUNET_MessageHeader *) &ibuf[mst->off]; | ||
191 | if (mst->pos - mst->off < want) | ||
192 | { | ||
193 | delta = GNUNET_MIN (want - (mst->pos - mst->off), size); | ||
194 | GNUNET_assert (mst->pos + delta <= mst->curr_buf); | ||
195 | GNUNET_memcpy (&ibuf[mst->pos], buf, delta); | ||
196 | mst->pos += delta; | ||
197 | buf += delta; | ||
198 | size -= delta; | ||
199 | } | ||
200 | if (mst->pos - mst->off < want) | ||
201 | { | ||
202 | if (purge) | ||
203 | { | ||
204 | mst->off = 0; | ||
205 | mst->pos = 0; | ||
206 | } | ||
207 | return GNUNET_OK; | ||
208 | } | ||
209 | if (one_shot == GNUNET_SYSERR) | ||
210 | { | ||
211 | /* cannot call callback again, but return value saying that | ||
212 | * we have another full message in the buffer */ | ||
213 | ret = GNUNET_NO; | ||
214 | goto copy; | ||
215 | } | ||
216 | if (one_shot == GNUNET_YES) | ||
217 | one_shot = GNUNET_SYSERR; | ||
218 | mst->off += want; | ||
219 | if (GNUNET_SYSERR == mst->cb (mst->cb_cls, client_identity, hdr)) | ||
220 | return GNUNET_SYSERR; | ||
221 | if (mst->off == mst->pos) | ||
222 | { | ||
223 | /* reset to beginning of buffer, it's free right now! */ | ||
224 | mst->off = 0; | ||
225 | mst->pos = 0; | ||
226 | } | ||
227 | } | ||
228 | GNUNET_assert (0 == mst->pos); | ||
229 | while (size > 0) | ||
230 | { | ||
231 | LOG (GNUNET_ERROR_TYPE_DEBUG, | ||
232 | "Server-mst has %u bytes left in inbound buffer\n", | ||
233 | (unsigned int) size); | ||
234 | if (size < sizeof (struct GNUNET_MessageHeader)) | ||
235 | break; | ||
236 | offset = (unsigned long) buf; | ||
237 | need_align = (0 != (offset % ALIGN_FACTOR)) ? GNUNET_YES : GNUNET_NO; | ||
238 | if (GNUNET_NO == need_align) | ||
239 | { | ||
240 | /* can try to do zero-copy and process directly from original buffer */ | ||
241 | hdr = (const struct GNUNET_MessageHeader *) buf; | ||
242 | want = ntohs (hdr->size); | ||
243 | if (want < sizeof (struct GNUNET_MessageHeader)) | ||
244 | { | ||
245 | GNUNET_break_op (0); | ||
246 | mst->off = 0; | ||
247 | return GNUNET_SYSERR; | ||
248 | } | ||
249 | if (size < want) | ||
250 | break; /* or not: buffer incomplete, so copy to private buffer... */ | ||
251 | if (one_shot == GNUNET_SYSERR) | ||
252 | { | ||
253 | /* cannot call callback again, but return value saying that | ||
254 | * we have another full message in the buffer */ | ||
255 | ret = GNUNET_NO; | ||
256 | goto copy; | ||
257 | } | ||
258 | if (one_shot == GNUNET_YES) | ||
259 | one_shot = GNUNET_SYSERR; | ||
260 | if (GNUNET_SYSERR == mst->cb (mst->cb_cls, client_identity, hdr)) | ||
261 | return GNUNET_SYSERR; | ||
262 | buf += want; | ||
263 | size -= want; | ||
264 | } | ||
265 | else | ||
266 | { | ||
267 | /* need to copy to private buffer to align; | ||
268 | * yes, we go a bit more spagetti than usual here */ | ||
269 | goto do_align; | ||
270 | } | ||
271 | } | ||
272 | copy: | ||
273 | if ((size > 0) && (!purge)) | ||
274 | { | ||
275 | if (size + mst->pos > mst->curr_buf) | ||
276 | { | ||
277 | mst->hdr = GNUNET_realloc (mst->hdr, size + mst->pos); | ||
278 | ibuf = (char *) mst->hdr; | ||
279 | mst->curr_buf = size + mst->pos; | ||
280 | } | ||
281 | GNUNET_assert (size + mst->pos <= mst->curr_buf); | ||
282 | GNUNET_memcpy (&ibuf[mst->pos], buf, size); | ||
283 | mst->pos += size; | ||
284 | } | ||
285 | if (purge) | ||
286 | { | ||
287 | mst->off = 0; | ||
288 | mst->pos = 0; | ||
289 | } | ||
290 | LOG (GNUNET_ERROR_TYPE_DEBUG, | ||
291 | "Server-mst leaves %u bytes in private buffer\n", | ||
292 | (unsigned int) (mst->pos - mst->off)); | ||
293 | return ret; | ||
294 | } | ||
295 | |||
296 | |||
297 | /** | ||
298 | * Destroys a tokenizer. | ||
299 | * | ||
300 | * @param mst tokenizer to destroy | ||
301 | */ | ||
302 | void | ||
303 | GNUNET_SERVER_mst_destroy (struct GNUNET_SERVER_MessageStreamTokenizer *mst) | ||
304 | { | ||
305 | GNUNET_free (mst->hdr); | ||
306 | GNUNET_free (mst); | ||
307 | } | ||
308 | |||
309 | |||
310 | |||
311 | /* end of server_mst.c */ | ||