Merge from build trunk.
[m6w6/libmemcached] / libmemcached / purge.cc
1 /* vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
2 *
3 * LibMemcached
4 *
5 * Copyright (C) 2011 Data Differential, http://datadifferential.com/
6 * Copyright (C) 2006-2009 Brian Aker
7 * All rights reserved.
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions are
11 * met:
12 *
13 * * Redistributions of source code must retain the above copyright
14 * notice, this list of conditions and the following disclaimer.
15 *
16 * * Redistributions in binary form must reproduce the above
17 * copyright notice, this list of conditions and the following disclaimer
18 * in the documentation and/or other materials provided with the
19 * distribution.
20 *
21 * * The names of its contributors may not be used to endorse or
22 * promote products derived from this software without specific prior
23 * written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
26 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
27 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
28 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
29 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
30 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
31 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
32 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
33 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
34 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
35 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
36 *
37 */
38
39
40 #include <libmemcached/common.h>
41
42
43 memcached_return_t memcached_purge(memcached_server_write_instance_st ptr)
44 {
45 memcached_return_t ret= MEMCACHED_SUCCESS;
46 memcached_st *root= (memcached_st *)ptr->root;
47
48 if (memcached_is_purging(ptr->root) || /* already purging */
49 (memcached_server_response_count(ptr) < ptr->root->io_msg_watermark &&
50 ptr->io_bytes_sent < ptr->root->io_bytes_watermark) ||
51 (ptr->io_bytes_sent >= ptr->root->io_bytes_watermark &&
52 memcached_server_response_count(ptr) < 2))
53 {
54 return MEMCACHED_SUCCESS;
55 }
56
57 /*
58 memcached_io_write and memcached_response may call memcached_purge
59 so we need to be able stop any recursion..
60 */
61 memcached_set_purging(root, true);
62
63 WATCHPOINT_ASSERT(ptr->fd != INVALID_SOCKET);
64 /*
65 Force a flush of the buffer to ensure that we don't have the n-1 pending
66 requests buffered up..
67 */
68 if (memcached_io_write(ptr) == false)
69 {
70 memcached_set_purging(root, true);
71
72 return memcached_set_error(*ptr, MEMCACHED_WRITE_FAILURE, MEMCACHED_AT);
73 }
74 WATCHPOINT_ASSERT(ptr->fd != INVALID_SOCKET);
75
76 uint32_t no_msg= memcached_server_response_count(ptr) - 1;
77 if (no_msg > 0)
78 {
79 memcached_result_st result;
80 memcached_result_st *result_ptr;
81
82 /*
83 * We need to increase the timeout, because we might be waiting for
84 * data to be sent from the server (the commands was in the output buffer
85 * and just flushed
86 */
87 const int32_t timeo= ptr->root->poll_timeout;
88 root->poll_timeout= 2000;
89
90 result_ptr= memcached_result_create(root, &result);
91 WATCHPOINT_ASSERT(result_ptr);
92
93 for (uint32_t x= 0; x < no_msg; x++)
94 {
95 memcached_result_reset(result_ptr);
96 memcached_return_t rc= memcached_read_one_response(ptr, result_ptr);
97 /*
98 * Purge doesn't care for what kind of command results that is received.
99 * The only kind of errors I care about if is I'm out of sync with the
100 * protocol or have problems reading data from the network..
101 */
102 if (rc== MEMCACHED_PROTOCOL_ERROR or rc == MEMCACHED_UNKNOWN_READ_FAILURE or rc == MEMCACHED_READ_FAILURE)
103 {
104 WATCHPOINT_ERROR(rc);
105 memcached_io_reset(ptr);
106 ret= rc;
107 #if 0
108 ret= memcached_set_error(*ptr, rc, MEMCACHED_AT);
109 #endif
110 }
111
112 if (ptr->root->callbacks != NULL)
113 {
114 memcached_callback_st cb = *ptr->root->callbacks;
115 if (memcached_success(rc))
116 {
117 for (uint32_t y= 0; y < cb.number_of_callback; y++)
118 {
119 rc = (*cb.callback[y])(ptr->root, result_ptr, cb.context);
120 if (rc != MEMCACHED_SUCCESS)
121 {
122 break;
123 }
124 }
125 }
126 }
127 }
128
129 memcached_result_free(result_ptr);
130 root->poll_timeout= timeo;
131 }
132 memcached_set_purging(root, false);
133
134 return ret;
135 }