1/*
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3 *
4 * @APPLE_LICENSE_HEADER_START@
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
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10 * 1.  Redistributions of source code must retain the above copyright
11 *     notice, this list of conditions and the following disclaimer.
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13 *     notice, this list of conditions and the following disclaimer in the
14 *     documentation and/or other materials provided with the distribution.
15 * 3.  Neither the name of Apple Inc. ("Apple") nor the names of its
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17 *     this software without specific prior written permission.
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21 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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30 * Portions of this software have been released under the following terms:
31 *
32 * (c) Copyright 1989-1993 OPEN SOFTWARE FOUNDATION, INC.
33 * (c) Copyright 1989-1993 HEWLETT-PACKARD COMPANY
34 * (c) Copyright 1989-1993 DIGITAL EQUIPMENT CORPORATION
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49 * Copyright (c) 2007, Novell, Inc. All rights reserved.
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51 * modification, are permitted provided that the following conditions
52 * are met:
53 *
54 * 1.  Redistributions of source code must retain the above copyright
55 *     notice, this list of conditions and the following disclaimer.
56 * 2.  Redistributions in binary form must reproduce the above copyright
57 *     notice, this list of conditions and the following disclaimer in the
58 *     documentation and/or other materials provided with the distribution.
59 * 3.  Neither the name of Novell Inc. nor the names of its contributors
60 *     may be used to endorse or promote products derived from this
61 *     this software without specific prior written permission.
62 *
63 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
64 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
65 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
66 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY
67 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
68 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
69 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
70 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
71 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
72 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
73 *
74 * @APPLE_LICENSE_HEADER_END@
75 */
76
77/*
78**
79**  NAME
80**
81**      rpc/runtime/comfork_cma.c
82**
83**  FACILITY:
84**
85**      Remote Procedure Call (RPC)
86**
87**  ABSTRACT:
88**
89**  Include CMA atfork grodiness.
90**
91**
92*/
93
94#include <commonp.h>
95#include <com.h>        /* Externals for Common Services component  */
96
97#if defined(ATFORK_SUPPORTED)
98
99#if defined(CMA_INCLUDE)
100
101/*
102 * This really doesn't belong here, but is here for pragmatic reasons.
103 */
104
105typedef void (*atfork_handler_ptr_t) (rpc_fork_stage_id_t /*stage*/);
106/*
107 * Save the address of the fork handler registered through atfork.
108 * This pointer should be saved ONLY once by rpc__cma_atfork(). If
109 * rpc__cma_atfork() is called more than once, which happens in the
110 * child context when rpc__init() is called, do not register the
111 * fork handler.
112 */
113INTERNAL atfork_handler_ptr_t  atfork_handler_ptr = NULL;
114
115INTERNAL struct atfork_user_data_t
116{
117    unsigned32  pid;    /* who registered */
118    unsigned32  pre;    /* How many times _pre_fork called */
119    unsigned32  post_p; /*                _post_fork_parent called */
120    unsigned32  post_c; /*                _post_fork_child called */
121} atfork_user_data;
122
123/* ========================================================================= */
124
125INTERNAL void _pre_fork (
126        cma_t_address   /*arg*/
127    );
128
129INTERNAL void _post_fork_child (
130        cma_t_address   /*arg*/
131    );
132
133INTERNAL void _post_fork_parent (
134        cma_t_address   /*arg*/
135    );
136
137/* ========================================================================= */
138
139/*
140 * _ P R E _ F O R K
141 *
142 * This procedure is called by the Pthreads library prior to calling
143 * the fork/vfork system call.
144 */
145INTERNAL void _pre_fork
146(
147  cma_t_address arg
148)
149{
150    RPC_DBG_PRINTF(rpc_e_dbg_atfork, 1,
151               ("(_pre_fork) entering, pid %d, pre %d, post_p %d, post_c %d\n",
152                    ((struct atfork_user_data_t *) arg)->pid,
153                    ((struct atfork_user_data_t *) arg)->pre,
154                    ((struct atfork_user_data_t *) arg)->post_p,
155                    ((struct atfork_user_data_t *) arg)->post_c);
156
157    ((struct atfork_user_data_t *) arg)->pre++;
158
159    if (rpc_g_initialized == true)
160        (*atfork_handler_ptr)(RPC_C_PREFORK);
161
162    RPC_DBG_PRINTF(rpc_e_dbg_atfork, 1,
163              ("(_pre_fork) returning, pid %d, pre %d, post_p %d, post_c %d\n",
164                    ((struct atfork_user_data_t *) arg)->pid,
165                    ((struct atfork_user_data_t *) arg)->pre,
166                    ((struct atfork_user_data_t *) arg)->post_p,
167                    ((struct atfork_user_data_t *) arg)->post_c);
168}
169
170/*
171 * _ P O S T _ F O R K _ C H I L D
172 *
173 * This procedure is called in the child of a forked process immediately
174 * after the fork is performed.
175 */
176
177INTERNAL void _post_fork_child
178(
179  cma_t_address arg
180)
181{
182    RPC_DBG_PRINTF(rpc_e_dbg_atfork, 1,
183        ("(_post_fork_child) entering, pid %d, pre %d, post_p %d, post_c %d\n",
184                    ((struct atfork_user_data_t *) arg)->pid,
185                    ((struct atfork_user_data_t *) arg)->pre,
186                    ((struct atfork_user_data_t *) arg)->post_p,
187                    ((struct atfork_user_data_t *) arg)->post_c);
188
189    ((struct atfork_user_data_t *) arg)->post_c++;
190
191    if (rpc_g_initialized == true)
192        (*atfork_handler_ptr)(RPC_C_POSTFORK_CHILD);
193
194    RPC_DBG_PRINTF(rpc_e_dbg_atfork, 1,
195       ("(_post_fork_child) returning, pid %d, pre %d, post_p %d, post_c %d\n",
196                    ((struct atfork_user_data_t *) arg)->pid,
197                    ((struct atfork_user_data_t *) arg)->pre,
198                    ((struct atfork_user_data_t *) arg)->post_p,
199                    ((struct atfork_user_data_t *) arg)->post_c);
200}
201
202/*
203 * _ P O S T _ F O R K _ P A R E N T
204 *
205 * This procedure is called in the parent of a forked process immediately
206 * after the fork is performed.
207 */
208
209INTERNAL void _post_fork_parent
210(
211  cma_t_address arg
212)
213{
214    RPC_DBG_PRINTF(rpc_e_dbg_atfork, 1,
215       ("(_post_fork_parent) entering, pid %d, pre %d, post_p %d, post_c %d\n",
216                    ((struct atfork_user_data_t *) arg)->pid,
217                    ((struct atfork_user_data_t *) arg)->pre,
218                    ((struct atfork_user_data_t *) arg)->post_p,
219                    ((struct atfork_user_data_t *) arg)->post_c);
220
221    ((struct atfork_user_data_t *) arg)->post_p++;
222
223    if (rpc_g_initialized == true)
224        (*atfork_handler_ptr)(RPC_C_POSTFORK_PARENT);
225
226    RPC_DBG_PRINTF(rpc_e_dbg_atfork, 1,
227      ("(_post_fork_parent) returning, pid %d, pre %d, post_p %d, post_c %d\n",
228                    ((struct atfork_user_data_t *) arg)->pid,
229                    ((struct atfork_user_data_t *) arg)->pre,
230                    ((struct atfork_user_data_t *) arg)->post_p,
231                    ((struct atfork_user_data_t *) arg)->post_c);
232}
233
234PRIVATE void rpc__cma_atfork
235(
236 void *handler
237)
238{
239    if (handler == NULL)
240        return;
241
242    /*
243     * Don't register it again!
244     */
245    if (atfork_handler_ptr != NULL)
246        return;
247
248    /*
249     * Save the address of the handler routine, and register our own
250     * handlers. (see note above)
251     */
252    atfork_handler_ptr = (atfork_handler_ptr_t) handler;
253    atfork_user_data.pid = (unsigned32) getpid();
254    atfork_user_data.pre = 0;
255    atfork_user_data.post_p = 0;
256    atfork_user_data.post_c = 0;
257
258    cma_atfork((cma_t_address)(&atfork_user_data), _pre_fork,
259               _post_fork_parent, _post_fork_child);
260}
261#endif  /* defined(CMA_INCLUDE) */
262
263#endif  /* defined(ATFORK_SUPPORTED) */
264