d9ba79c7b28bdd36aee9251fe1b8e83435296082
[m6w6/libmemcached] / libmemcached / util / pid.cc
1 /* vim:expandtab:shiftwidth=2:tabstop=2:smarttab:
2 *
3 * Libmemcached library
4 *
5 * Copyright (C) 2011 Data Differential, http://datadifferential.com/
6 * Copyright (C) 2010 Brian Aker All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions are
10 * met:
11 *
12 * * Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 *
15 * * Redistributions in binary form must reproduce the above
16 * copyright notice, this list of conditions and the following disclaimer
17 * in the documentation and/or other materials provided with the
18 * distribution.
19 *
20 * * The names of its contributors may not be used to endorse or
21 * promote products derived from this software without specific prior
22 * written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
25 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
26 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
27 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
28 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
29 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
30 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
31 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
32 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
34 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35 *
36 * Summary: connects to a host, and determines what its pid is
37 *
38 */
39
40 #include <libmemcached/common.h>
41 #include <libmemcached/memcached_util.h>
42
43
44 // Never look at the stat object directly.
45
46
47 pid_t libmemcached_util_getpid(const char *hostname, in_port_t port, memcached_return_t *ret)
48 {
49 pid_t pid= -1;
50
51 memcached_return_t unused;
52 if (not ret)
53 ret= &unused;
54
55 memcached_st *memc_ptr= memcached_create(NULL);
56 if (not memc_ptr)
57 {
58 *ret= MEMCACHED_MEMORY_ALLOCATION_FAILURE;
59 return pid;
60 }
61
62 memcached_return_t rc= memcached_server_add(memc_ptr, hostname, port);
63 if (memcached_success(rc))
64 {
65 memcached_stat_st *stat= memcached_stat(memc_ptr, NULL, &rc);
66 if (stat and stat->pid > 0)
67 {
68 pid= stat->pid;
69 }
70 else if (memcached_failed(rc) and rc == MEMCACHED_SOME_ERRORS)
71 {
72 memcached_server_instance_st instance=
73 memcached_server_instance_by_position(memc_ptr, 0);
74
75 if (instance and instance->error_messages)
76 {
77 rc= memcached_server_error_return(instance);
78 }
79 }
80 else if (memcached_success(rc))
81 {
82 rc= MEMCACHED_UNKNOWN_STAT_KEY; // Something went wrong if this happens
83 }
84
85 memcached_stat_free(memc_ptr, stat);
86 }
87 memcached_free(memc_ptr);
88
89 *ret= rc;
90
91 return pid;
92 }
93