root / prex-0.9.0 / usr / server / proc / proc_exit.c @ 03e9c04a
History | View | Annotate | Download (5.12 KB)
1 | 03e9c04a | Brad Neuman | /*
|
---|---|---|---|
2 | * Copyright (c) 2005-2008, Kohsuke Ohtani
|
||
3 | * All rights reserved.
|
||
4 | *
|
||
5 | * Redistribution and use in source and binary forms, with or without
|
||
6 | * modification, are permitted provided that the following conditions
|
||
7 | * are met:
|
||
8 | * 1. Redistributions of source code must retain the above copyright
|
||
9 | * notice, this list of conditions and the following disclaimer.
|
||
10 | * 2. Redistributions in binary form must reproduce the above copyright
|
||
11 | * notice, this list of conditions and the following disclaimer in the
|
||
12 | * documentation and/or other materials provided with the distribution.
|
||
13 | * 3. Neither the name of the author nor the names of any co-contributors
|
||
14 | * may be used to endorse or promote products derived from this software
|
||
15 | * without specific prior written permission.
|
||
16 | *
|
||
17 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
|
||
18 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
||
19 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
||
20 | * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
|
||
21 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
|
||
22 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
|
||
23 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
|
||
24 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
|
||
25 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
|
||
26 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
||
27 | * SUCH DAMAGE.
|
||
28 | */
|
||
29 | |||
30 | /*
|
||
31 | * exit.c - process exit and wait
|
||
32 | */
|
||
33 | |||
34 | #include <sys/prex.h> |
||
35 | #include <ipc/proc.h> |
||
36 | #include <sys/list.h> |
||
37 | |||
38 | #include <unistd.h> |
||
39 | #include <errno.h> |
||
40 | #include <signal.h> |
||
41 | |||
42 | #include "proc.h" |
||
43 | |||
44 | /*
|
||
45 | * Exit process.
|
||
46 | *
|
||
47 | * process_exit() sets the process state to zombie state, and it
|
||
48 | * saves the exit code for waiting process.
|
||
49 | */
|
||
50 | int
|
||
51 | sys_exit(int exitcode)
|
||
52 | { |
||
53 | struct proc *child, *parent;
|
||
54 | list_t head, n; |
||
55 | int error;
|
||
56 | |||
57 | DPRINTF(("proc: exit pid=%d code=%x\n", curproc->p_pid, exitcode));
|
||
58 | |||
59 | if (curproc->p_stat == SZOMB)
|
||
60 | return EBUSY;
|
||
61 | |||
62 | /*
|
||
63 | * Enter zombie state.
|
||
64 | */
|
||
65 | curproc->p_stat = SZOMB; |
||
66 | curproc->p_exitcode = exitcode; |
||
67 | p_remove(curproc); |
||
68 | |||
69 | /*
|
||
70 | * Set the parent pid of all child processes to 1 (init).
|
||
71 | */
|
||
72 | head = &curproc->p_children; |
||
73 | n = list_first(head); |
||
74 | while (n != head) {
|
||
75 | child = list_entry(n, struct proc, p_sibling);
|
||
76 | n = list_next(n); |
||
77 | |||
78 | child->p_parent = &initproc; |
||
79 | list_remove(&child->p_sibling); |
||
80 | list_insert(&initproc.p_children, &child->p_sibling); |
||
81 | } |
||
82 | |||
83 | /*
|
||
84 | * Resume parent process which is wating in vfork.
|
||
85 | */
|
||
86 | parent = curproc->p_parent; |
||
87 | if (parent != NULL && parent->p_vforked) { |
||
88 | vfork_end(parent); |
||
89 | |||
90 | /*
|
||
91 | * The child task loses its stack data.
|
||
92 | * So, it can not run anymore.
|
||
93 | */
|
||
94 | error = task_terminate(curproc->p_task); |
||
95 | if (error)
|
||
96 | sys_panic("proc: can not terminate a task for exit");
|
||
97 | } |
||
98 | |||
99 | /* Send a signal to the parent process. */
|
||
100 | DPRINTF(("proc: exit send SIGCHLD to pid=%d\n",
|
||
101 | curproc->p_parent->p_pid)); |
||
102 | exception_raise(curproc->p_parent->p_task, SIGCHLD); |
||
103 | |||
104 | return 0; |
||
105 | } |
||
106 | |||
107 | /*
|
||
108 | * Stop process.
|
||
109 | *
|
||
110 | * This is similar with exit(), but it does not update the parent
|
||
111 | * pid of any child processes.
|
||
112 | */
|
||
113 | int
|
||
114 | stop(int exitcode)
|
||
115 | { |
||
116 | |||
117 | DPRINTF(("proc: stop code=%x\n", exitcode));
|
||
118 | |||
119 | if (curproc->p_stat == SZOMB)
|
||
120 | return EBUSY;
|
||
121 | |||
122 | curproc->p_stat = SSTOP; |
||
123 | curproc->p_exitcode = exitcode; |
||
124 | |||
125 | /* Send a signal to the parent process. */
|
||
126 | exception_raise(curproc->p_parent->p_task, SIGCHLD); |
||
127 | |||
128 | return 0; |
||
129 | } |
||
130 | |||
131 | /*
|
||
132 | * Find the zombie process in the child processes. It just
|
||
133 | * returns the pid and exit code if it find at least one zombie
|
||
134 | * process.
|
||
135 | *
|
||
136 | * The library stub for waitpid() will wait the SIGCHLD signal in
|
||
137 | * the stub code if there is no zombie process in child process.
|
||
138 | * This signal is sent by proc_exit() or proc_stop() routines in
|
||
139 | * the process server.
|
||
140 | */
|
||
141 | int
|
||
142 | sys_waitpid(pid_t pid, int *status, int options, pid_t *retval) |
||
143 | { |
||
144 | pid_t pid_child; |
||
145 | int code, match;
|
||
146 | struct proc *p;
|
||
147 | list_t head, n; |
||
148 | |||
149 | DPRINTF(("proc: wait pid=%d options=%x\n", pid, options));
|
||
150 | |||
151 | if (list_empty(&curproc->p_children))
|
||
152 | return ECHILD; /* No child process */ |
||
153 | |||
154 | /* Set the default pid and exit code */
|
||
155 | pid_child = 0;
|
||
156 | code = 0;
|
||
157 | |||
158 | /*
|
||
159 | * Check all processes.
|
||
160 | */
|
||
161 | p = NULL;
|
||
162 | head = &curproc->p_children; |
||
163 | for (n = list_first(head); n != head; n = list_next(n)) {
|
||
164 | p = list_entry(n, struct proc, p_sibling);
|
||
165 | |||
166 | /*
|
||
167 | * Check if pid matches.
|
||
168 | */
|
||
169 | match = 0;
|
||
170 | if (pid > 0) { |
||
171 | /*
|
||
172 | * Wait a specific child process.
|
||
173 | */
|
||
174 | if (p->p_pid == pid)
|
||
175 | match = 1;
|
||
176 | } else if (pid == 0) { |
||
177 | /*
|
||
178 | * Wait a process who has same pgid.
|
||
179 | */
|
||
180 | if (p->p_pgrp->pg_pgid == curproc->p_pgrp->pg_pgid)
|
||
181 | match = 1;
|
||
182 | } else if (pid != -1) { |
||
183 | /*
|
||
184 | * Wait a specific pgid.
|
||
185 | */
|
||
186 | if (p->p_pgrp->pg_pgid == -pid)
|
||
187 | match = 1;
|
||
188 | } else {
|
||
189 | /*
|
||
190 | * pid = -1 means wait any child process.
|
||
191 | */
|
||
192 | match = 1;
|
||
193 | } |
||
194 | if (match) {
|
||
195 | /*
|
||
196 | * Get the exit code.
|
||
197 | */
|
||
198 | if (p->p_stat == SSTOP) {
|
||
199 | pid_child = p->p_pid; |
||
200 | code = p->p_exitcode; |
||
201 | break;
|
||
202 | } else if (p->p_stat == SZOMB) { |
||
203 | pid_child = p->p_pid; |
||
204 | code = p->p_exitcode; |
||
205 | cleanup(p); |
||
206 | break;
|
||
207 | } |
||
208 | } |
||
209 | } |
||
210 | *status = code; |
||
211 | *retval = pid_child; |
||
212 | return 0; |
||
213 | } |