summaryrefslogtreecommitdiff
path: root/librabbitmq/amqp_connection.c
blob: 17a30d19271ed1714fa9900028c60d0922dbabad (plain)
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
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <stdint.h>
#include <errno.h>

#include <unistd.h>
#include <sys/uio.h>

#include "amqp.h"
#include "amqp_framing.h"
#include "amqp_private.h"

#include <assert.h>

#define INITIAL_FRAME_POOL_PAGE_SIZE 65536
#define INITIAL_DECODING_POOL_PAGE_SIZE 131072
#define INITIAL_INBOUND_SOCK_BUFFER_SIZE 131072

#define ENFORCE_STATE(statevec, statenum)				\
  {									\
    amqp_connection_state_t _check_state = (statevec);			\
    int _wanted_state = (statenum);					\
    amqp_assert(_check_state->state == _wanted_state,			\
		"Programming error: invalid AMQP connection state: expected %d, got %d", \
		_wanted_state,						\
		_check_state->state);					\
  }

amqp_connection_state_t amqp_new_connection(void) {
  amqp_connection_state_t state =
    (amqp_connection_state_t) calloc(1, sizeof(struct amqp_connection_state_t_));

  if (state == NULL) {
    return NULL;
  }

  init_amqp_pool(&state->frame_pool, INITIAL_FRAME_POOL_PAGE_SIZE);
  init_amqp_pool(&state->decoding_pool, INITIAL_DECODING_POOL_PAGE_SIZE);

  state->state = CONNECTION_STATE_IDLE;

  state->inbound_buffer.bytes = NULL;
  state->outbound_buffer.bytes = NULL;
  if (amqp_tune_connection(state, INITIAL_FRAME_POOL_PAGE_SIZE) != 0) {
    empty_amqp_pool(&state->frame_pool);
    empty_amqp_pool(&state->decoding_pool);
    free(state);
    return NULL;
  }

  state->inbound_offset = 0;
  state->target_size = HEADER_SIZE;

  state->sockfd = -1;
  state->sock_inbound_buffer.len = INITIAL_INBOUND_SOCK_BUFFER_SIZE;
  state->sock_inbound_buffer.bytes = malloc(INITIAL_INBOUND_SOCK_BUFFER_SIZE);
  if (state->sock_inbound_buffer.bytes == NULL) {
    amqp_destroy_connection(state);
    return NULL;
  }

  state->sock_inbound_offset = 0;
  state->sock_inbound_limit = 0;

  state->first_queued_frame = NULL;
  state->last_queued_frame = NULL;

  return state;
}

void amqp_set_sockfd(amqp_connection_state_t state,
		     int sockfd)
{
  state->sockfd = sockfd;
}

int amqp_tune_connection(amqp_connection_state_t state,
			 int frame_max)
{
  void *newbuf;

  ENFORCE_STATE(state, CONNECTION_STATE_IDLE);

  state->frame_max = frame_max;

  empty_amqp_pool(&state->frame_pool);
  init_amqp_pool(&state->frame_pool, frame_max);

  state->inbound_buffer.len = frame_max;
  state->outbound_buffer.len = frame_max;
  newbuf = realloc(state->outbound_buffer.bytes, frame_max);
  if (newbuf == NULL) {
    amqp_destroy_connection(state);
    return -ENOMEM;
  }
  state->outbound_buffer.bytes = newbuf;

  return 0;
}

void amqp_destroy_connection(amqp_connection_state_t state) {
  empty_amqp_pool(&state->frame_pool);
  empty_amqp_pool(&state->decoding_pool);
  free(state->outbound_buffer.bytes);
  free(state->sock_inbound_buffer.bytes);
  free(state);
}

static void return_to_idle(amqp_connection_state_t state) {
  state->inbound_buffer.bytes = NULL;
  state->inbound_offset = 0;
  state->target_size = HEADER_SIZE;
  state->state = CONNECTION_STATE_IDLE;
}

int amqp_handle_input(amqp_connection_state_t state,
		      amqp_bytes_t received_data,
		      amqp_frame_t *decoded_frame)
{
  int total_bytes_consumed = 0;
  int bytes_consumed;

  /* Returning frame_type of zero indicates either insufficient input,
     or a complete, ignored frame was read. */
  decoded_frame->frame_type = 0;

 read_more:
  if (received_data.len == 0) {
    return total_bytes_consumed;
  }

  if (state->state == CONNECTION_STATE_IDLE) {
    state->inbound_buffer.bytes = amqp_pool_alloc(&state->frame_pool, state->inbound_buffer.len);
    state->state = CONNECTION_STATE_WAITING_FOR_HEADER;
  }

  bytes_consumed = state->target_size - state->inbound_offset;
  if (received_data.len < bytes_consumed) {
    bytes_consumed = received_data.len;
  }

  E_BYTES(state->inbound_buffer, state->inbound_offset, bytes_consumed, received_data.bytes);
  state->inbound_offset += bytes_consumed;
  total_bytes_consumed += bytes_consumed;

  assert(state->inbound_offset <= state->target_size);

  if (state->inbound_offset < state->target_size) {
    return total_bytes_consumed;
  }

  switch (state->state) {
    case CONNECTION_STATE_WAITING_FOR_HEADER:
      if (D_8(state->inbound_buffer, 0) == AMQP_PSEUDOFRAME_PROTOCOL_HEADER &&
	  D_16(state->inbound_buffer, 1) == AMQP_PSEUDOFRAME_PROTOCOL_CHANNEL)
      {
	state->target_size = 8;
	state->state = CONNECTION_STATE_WAITING_FOR_PROTOCOL_HEADER;
      } else {
	state->target_size = D_32(state->inbound_buffer, 3) + HEADER_SIZE + FOOTER_SIZE;
	state->state = CONNECTION_STATE_WAITING_FOR_BODY;
      }

      /* Wind buffer forward, and try to read some body out of it. */
      received_data.len -= bytes_consumed;
      received_data.bytes = ((char *) received_data.bytes) + bytes_consumed;
      goto read_more;

    case CONNECTION_STATE_WAITING_FOR_BODY: {
      int frame_type = D_8(state->inbound_buffer, 0);

#if 0
      printf("recving:\n");
      amqp_dump(state->inbound_buffer.bytes, state->target_size);
#endif

      /* Check frame end marker (footer) */
      if (D_8(state->inbound_buffer, state->target_size - 1) != AMQP_FRAME_END) {
	return -EINVAL;
      }

      decoded_frame->channel = D_16(state->inbound_buffer, 1);

      switch (frame_type) {
	case AMQP_FRAME_METHOD: {
	  amqp_bytes_t encoded;

	  /* Four bytes of method ID before the method args. */
	  encoded.len = state->target_size - (HEADER_SIZE + 4 + FOOTER_SIZE);
	  encoded.bytes = D_BYTES(state->inbound_buffer, HEADER_SIZE + 4, encoded.len);

	  decoded_frame->frame_type = AMQP_FRAME_METHOD;
	  decoded_frame->payload.method.id = D_32(state->inbound_buffer, HEADER_SIZE);
	  AMQP_CHECK_RESULT(amqp_decode_method(decoded_frame->payload.method.id,
					       &state->decoding_pool,
					       encoded,
					       &decoded_frame->payload.method.decoded));
	  break;
	}

	case AMQP_FRAME_HEADER: {
	  amqp_bytes_t encoded;

	  /* 12 bytes for properties header. */
	  encoded.len = state->target_size - (HEADER_SIZE + 12 + FOOTER_SIZE);
	  encoded.bytes = D_BYTES(state->inbound_buffer, HEADER_SIZE + 12, encoded.len);

	  decoded_frame->frame_type = AMQP_FRAME_HEADER;
	  decoded_frame->payload.properties.class_id = D_16(state->inbound_buffer, HEADER_SIZE);
	  decoded_frame->payload.properties.body_size = D_64(state->inbound_buffer, HEADER_SIZE+4);
	  AMQP_CHECK_RESULT(amqp_decode_properties(decoded_frame->payload.properties.class_id,
						   &state->decoding_pool,
						   encoded,
						   &decoded_frame->payload.properties.decoded));
	  break;
	}

	case AMQP_FRAME_BODY: {
	  size_t fragment_len = state->target_size - (HEADER_SIZE + FOOTER_SIZE);

	  decoded_frame->frame_type = AMQP_FRAME_BODY;
	  decoded_frame->payload.body_fragment.len = fragment_len;
	  decoded_frame->payload.body_fragment.bytes =
	    D_BYTES(state->inbound_buffer, HEADER_SIZE, fragment_len);
	  break;
	}

	default:
	  /* Ignore the frame by not changing frame_type away from 0. */
	  break;
      }

      return_to_idle(state);
      return total_bytes_consumed;
    }

    case CONNECTION_STATE_WAITING_FOR_PROTOCOL_HEADER:
      decoded_frame->frame_type = AMQP_PSEUDOFRAME_PROTOCOL_HEADER;
      decoded_frame->channel = AMQP_PSEUDOFRAME_PROTOCOL_CHANNEL;
      amqp_assert(D_8(state->inbound_buffer, 3) == (uint8_t) 'P',
		  "Invalid protocol header received");
      decoded_frame->payload.protocol_header.transport_high = D_8(state->inbound_buffer, 4);
      decoded_frame->payload.protocol_header.transport_low = D_8(state->inbound_buffer, 5);
      decoded_frame->payload.protocol_header.protocol_version_major = D_8(state->inbound_buffer, 6);
      decoded_frame->payload.protocol_header.protocol_version_minor = D_8(state->inbound_buffer, 7);

      return_to_idle(state);
      return total_bytes_consumed;

    default:
      amqp_assert(0, "Internal error: invalid amqp_connection_state_t->state %d", state->state);
  }
}

amqp_boolean_t amqp_release_buffers_ok(amqp_connection_state_t state) {
  return (state->state == CONNECTION_STATE_IDLE) && (state->first_queued_frame == NULL);
}

void amqp_release_buffers(amqp_connection_state_t state) {
  ENFORCE_STATE(state, CONNECTION_STATE_IDLE);

  amqp_assert(state->first_queued_frame == NULL,
	      "Programming error: attempt to amqp_release_buffers while waiting events enqueued");

  recycle_amqp_pool(&state->frame_pool);
  recycle_amqp_pool(&state->decoding_pool);
}

void amqp_maybe_release_buffers(amqp_connection_state_t state) {
  if (amqp_release_buffers_ok(state)) {
    amqp_release_buffers(state);
  }
}

static int inner_send_frame(amqp_connection_state_t state,
			    amqp_frame_t const *frame,
			    amqp_bytes_t *encoded,
			    int *payload_len)
{
  int separate_body;

  E_8(state->outbound_buffer, 0, frame->frame_type);
  E_16(state->outbound_buffer, 1, frame->channel);
  switch (frame->frame_type) {
    case AMQP_FRAME_METHOD:
      E_32(state->outbound_buffer, HEADER_SIZE, frame->payload.method.id);
      encoded->len = state->outbound_buffer.len - (HEADER_SIZE + 4 + FOOTER_SIZE);
      encoded->bytes = D_BYTES(state->outbound_buffer, HEADER_SIZE + 4, encoded->len);
      *payload_len = AMQP_CHECK_RESULT(amqp_encode_method(frame->payload.method.id,
							  frame->payload.method.decoded,
							  *encoded)) + 4;
      separate_body = 0;
      break;

    case AMQP_FRAME_HEADER:
      E_16(state->outbound_buffer, HEADER_SIZE, frame->payload.properties.class_id);
      E_16(state->outbound_buffer, HEADER_SIZE+2, 0); /* "weight" */
      E_64(state->outbound_buffer, HEADER_SIZE+4, frame->payload.properties.body_size);
      encoded->len = state->outbound_buffer.len - (HEADER_SIZE + 12 + FOOTER_SIZE);
      encoded->bytes = D_BYTES(state->outbound_buffer, HEADER_SIZE + 12, encoded->len);
      *payload_len = AMQP_CHECK_RESULT(amqp_encode_properties(frame->payload.properties.class_id,
							      frame->payload.properties.decoded,
							      *encoded)) + 12;
      separate_body = 0;
      break;

    case AMQP_FRAME_BODY:
      *encoded = frame->payload.body_fragment;
      *payload_len = encoded->len;
      separate_body = 1;
      break;

    default:
      return -EINVAL;
  }

  E_32(state->outbound_buffer, 3, *payload_len);
  if (!separate_body) {
    E_8(state->outbound_buffer, *payload_len + HEADER_SIZE, AMQP_FRAME_END);
  }

#if 0
  if (separate_body) {
    printf("sending body frame (header):\n");
    amqp_dump(state->outbound_buffer.bytes, HEADER_SIZE);
    printf("sending body frame (payload):\n");
    amqp_dump(encoded->bytes, *payload_len);
  } else {
    printf("sending:\n");
    amqp_dump(state->outbound_buffer.bytes, *payload_len + HEADER_SIZE + FOOTER_SIZE);
  }
#endif

  return separate_body;
}

int amqp_send_frame(amqp_connection_state_t state,
		    amqp_frame_t const *frame)
{
  amqp_bytes_t encoded;
  int payload_len;
  int separate_body;

  separate_body = inner_send_frame(state, frame, &encoded, &payload_len);
  switch (separate_body) {
    case 0:
      AMQP_CHECK_RESULT(write(state->sockfd,
			      state->outbound_buffer.bytes,
			      payload_len + (HEADER_SIZE + FOOTER_SIZE)));
      return 0;

    case 1:
      AMQP_CHECK_RESULT(write(state->sockfd, state->outbound_buffer.bytes, HEADER_SIZE));
      AMQP_CHECK_RESULT(write(state->sockfd, encoded.bytes, payload_len));
      {
	assert(FOOTER_SIZE == 1);
	char frame_end_byte = AMQP_FRAME_END;
	AMQP_CHECK_RESULT(write(state->sockfd, &frame_end_byte, FOOTER_SIZE));
      }
      return 0;

    default:
      return separate_body;
  }
}

int amqp_send_frame_to(amqp_connection_state_t state,
		       amqp_frame_t const *frame,
		       amqp_output_fn_t fn,
		       void *context)
{
  amqp_bytes_t encoded;
  int payload_len;
  int separate_body;

  separate_body = inner_send_frame(state, frame, &encoded, &payload_len);
  switch (separate_body) {
    case 0:
      AMQP_CHECK_RESULT(fn(context,
			   state->outbound_buffer.bytes,
			   payload_len + (HEADER_SIZE + FOOTER_SIZE)));
      return 0;

    case 1:
      AMQP_CHECK_RESULT(fn(context, state->outbound_buffer.bytes, HEADER_SIZE));
      AMQP_CHECK_RESULT(fn(context, encoded.bytes, payload_len));
      {
	assert(FOOTER_SIZE == 1);
	char frame_end_byte = AMQP_FRAME_END;
	AMQP_CHECK_RESULT(fn(context, &frame_end_byte, FOOTER_SIZE));
      }
      return 0;

    default:
      return separate_body;
  }
}